OBJECTIVES: The objective of this clinical study was to evaluate the effect of a bisphosphonate coating on a titanium implant on the implant stability quotient (ISQ) and the radiographic marginal bone levels at implants during early healing (2-8 weeks).

MATERIALS AND METHODS: In a randomized double-blind trial with internal controls, 16 patients received a dental implant coated with zoledronate and one uncoated implant as a control. The coated and uncoated implants which were visually indistinguishable were bone level titanium implants with a moderately rough surface and a microthreaded neck. ISQ values were obtained at insertion and at 2, 4, 6, and 8 weeks. Radiographs were obtained at insertion and at 8 weeks. The primary outcome was the difference in ISQ values between the coated implants and the control implants at 4 and 6 weeks, corrected for insertion values. The secondary outcome was loss of marginal bone level from insertion to 8 weeks.

RESULTS: Implant stability quotient values remained largely constant over the 8 weeks, and there was no significant difference between coated and uncoated implants at any time point. There was 0.12 (SD 0.10) mm marginal bone loss at the control implants and 0.04 (SD 0.08) mm at the coated implants. The difference was 0.17 mm; SD 0.14; p < 0.006). On blind qualitative scoring, 13 of the 15 control implants and two of 15 coated implants showed small marginal bone defects (p = 0.003).

CONCLUSIONS: There were no statistically significant differences observed in ISQ values between the coated and uncoated implants during the early healing. There was less marginal bone loss at the coated implants.

This pilot study evaluates the clinical stability of bisphosphonate-coated dental implants placed using a two-stage surgical procedure in five patients. Each patient received seven regular Branemark implants, one of which was coated with bisphosphonate in a fibrinogen matrix. The coated implant was inserted where the bone was expected to have the least favourable quality. The level of the marginal bone around each implant was measured by intraoral periapical radiographs and implant stability was recorded using resonance frequency measurements. Frequency values (ISQ) were obtained peroperatively before flap closure and after 6 months at abutment connection. At abutment connection the bisphosphonate-coated implants were removed en bloc in two patients for histological examination. An animal experiment had previously confirmed that gamma-sterilization did not reduce bioactivity of the bisphosphonate coating. In each patient, the bisphosphonate-coated implant showed the largest improvement in ISQ level of all implants. Their values at the start tended to be lower, and the absolute value at 6 months did not differ. No complications occurred with the coated implants. Histology showed no abnormalities. Improvement in ISQ values was an expected effect of the bisphosphonate coating, but could be due to the choice of insertion site. This finding warrants a randomized blinded study.

We compared the effect of a sclerostin antibody to that of a clinically relevant dose of parathyroid hormone (PTH) in a rat model for metaphyseal bone healing. Screws of steel or poly methyl methacrylate (PMMA) were inserted bilaterally into the proximal tibia of young male rats. During 4 weeks the animals then received injections of either phosphate buffered saline (control), sclerostin antibody (25mg/kg, twice weekly) or PTH (5 mu g/kg, daily). The healing response around the screws was then assessed by mechanical testing and X-ray microtomography (mu CT). To distinguish between effects on healing and general effects on the skeleton, other untraumatized bone sites and serum biomarkers were also assessed. After 4 weeks of treatment, PTH yielded a 48% increase in screw pull-out force compared to control (p=0.03), while the antibody had no significant effect. In contrast, the antibody increased femoral cortical and vertebral strength where PTH had no significant effect. mu CT showed only slight changes that were statistically significant for the antibody mainly at cortical sites. The results suggest that a relatively low dose of PTH stimulates metaphyseal repair (screw fixation) specifically, whereas the sclerostin antibody has wide-spread effects, mainly on cortical bone, with less influence on metaphyseal healing.

Background

In obese patients, total hip arthroplasty (THA) can be technically demanding with increased perioperative risks. The aim of this prospective cohort study is to evaluate the effect of body mass index (BMI) on radiological restoration of femoral offset (FO) and leg length as well as acetabular cup positioning.

Methods

In this prospective study, patients with unilateral primary osteoarthritis (OA) treated with THA between September 2010 and December 2013 were considered for inclusion. The perioperative plain radiographs were standardised and used to measure the preoperative degree of hip osteoarthritis, postoperative FO, leg length discrepancy (LLD), acetabular component inclination and anteversion.

Results

We included 213 patients (74.5% of those considered for inclusion) with a mean BMI of 27.7 (SD 4.5) in the final analysis. The postoperative FO was improper in 55% and the LLD in 15%, while the cup inclination and anteversion were improper in 13 and 23% of patients respectively. A multivariable logistic regression model identified BMI as the only factor that affected LLD. Increased BMI increased the risk of LLD (OR 1.14, 95% CI 1.04 to 1.25). No other factors included in the model affected any of the primary or secondary outcomes.

Conclusion

Increased BMI showed a negative effect on restoration of post-THA leg length but not on restoration of FO or positioning of the acetabular cup. Age, gender, OA duration or radiological severity and surgeon’s experience showed no relation to post-THA restoration of FO, leg length or cup positioning.

Background and Objectives: Chronic painful midportion Achilles combined with plantaris tendinopathy can be a troublesome condition to treat. The objective was to prospectively follow patients subjected to ultrasound (US)- and color doppler (CD)-guided wide awake, local anesthetic, no-tourniquet (WALANT) surgery in a private setting. Material and Methods: Twenty-six Swedish patients (17 men and 9 women, mean age 50 years (range 29-62)) and eight international male patients (mean age of 38 years (range 25-71)) with combined midportion Achilles and plantaris tendinopathy in 45 tendons altogether were included. All patients had had &gt;6 months of pain and had tried non-surgical treatment with eccentric training, without effect. US + CD-guided surgical scraping of the ventral Achilles tendon and plantaris removal under local anesthesia was performed on all patients. A 4-6-week rehabilitation protocol with an immediate full-weight-bearing tendon loading regime was used. The VISA-A score and a study-specific questionnaire evaluating physical activity level and subjective satisfaction with the treatment were used for evaluation. Results: At the 1-year follow-up, 32/34 patients (43 tendons) were satisfied with the treatment result and had returned to their pre-injury Achilles tendon loading activity. There were two dropouts (two tendons). For the Swedish patients, the mean VISA-A score increased from 34 (0-64) before surgery to 93 (61-100) after surgery (p &lt; 0.001). There were two complications, one wound rupture and one superficial skin infection. Conclusions: For patients suffering from painful midportion Achilles tendinopathy and plantaris tendinopathy, US + CD-guided surgical Achilles tendon scraping and plantaris tendon removal showed a high satisfaction rate and good functional results 1 year after surgery.

We investigated the difference between postoperative rehabilitation with or without adjunctive intermittent pneumatic compression therapy following distal radial fracture treated with volar plating. A total of 115 patients were randomized to a control or to an experimental group. After 4 weeks of immobilization the experimental group received intermittent pneumatic compression therapy in addition to conventional postoperative rehabilitation. Primary outcome up to 1 year postoperatively was assessed using the Canadian Occupational Performance Measure. No significant differences between groups were found. There were no clinically relevant differences regarding the secondary outcome measures swelling, strength, pain and flexibility. We conclude that postoperative intermittent pneumatic compression treatment had no major benefits. The results of the present study do not support general use of intermittent pneumatic compression initiated 4 weeks following volar plating surgery for distal radial fracture. Level of evidence: I

Wear debris particles released from prosthetic bearing surfaces and mechanical instability of implants are two main causes of periprosthetic osteolysis. While particle-induced loosening has been studied extensively, mechanisms through which mechanical factors lead to implant loosening have been less investigated. This study compares the transcriptional profiles associated with osteolysis in a rat model for aseptic loosening, induced by either mechanical instability or titanium particles. Rats were exposed to mechanical instability or titanium particles. After 15 min, 3, 48 or 120 h from start of the stimulation, gene expression changes in periprosthetic bone tissue was determined by microarray analysis. Microarray data were analyzed by PANTHER Gene List Analysis tool and Ingenuity Pathway Analysis (IPA). Both types of osteolytic stimulation led to gene regulation in comparison to unstimulated controls after 3, 48 or 120 h. However, when mechanical instability was compared to titanium particles, no gene showed a statistically significant difference (fold change = ± 1.5 and adjusted p-value = 0.05) at any time point. There was a remarkable similarity in numbers and functional classification of regulated genes. Pathway analysis showed several inflammatory pathways activated by both stimuli, including Acute Phase Response signaling, IL-6 signaling and Oncostatin M signaling. Quantitative PCR confirmed the changes in expression of key genes involved in osteolysis observed by global transcriptomics. Inflammatory mediators including interleukin (IL)-6, IL-1ß, chemokine (C-C motif) ligand (CCL)2, prostaglandin-endoperoxide synthase (Ptgs)2 and leukemia inhibitory factor (LIF) showed strong upregulation, as assessed by both microarray and qPCR. By investigating genome-wide expression changes we show that, despite the different nature of mechanical implant instability and titanium particles, osteolysis seems to be induced through similar biological and signaling pathways in this rat model for aseptic loosening. Pathways associated to the innate inflammatory response appear to be a major driver for osteolysis. Our findings implicate early restriction of inflammation to be critical to prevent or mitigate osteolysis and aseptic loosening of orthopedic implants.

BackgroundIn Sweden, most children with slipped capital femoral epiphysis (SCFE) are operated on with a single smooth pin or a short-threaded screw, allowing further growth of the femoral neck. Using the Swedish Pediatric Orthopaedic Quality registry, SPOQ, we investigated whether angular remodelling occurs adjacent to the proximal femoral epiphysis after fixation of SCFE using implants, allowing continued growth of the femoral neck.MethodsDuring 2008-2010 a total national population of 155 children were reported to the SPOQ registry. Following our strict inclusion criteria, radiographs of 51 hips were further assessed. The lateral Head Shaft Angle (HSA), the Notzli 3-point alpha-angle, the anatomic alpha-angle, and the Anterior Offset Ratio (AOR) on the first postoperative radiographs and at follow-up were measured to describe the occurrence of remodelling. Slip severity was categorised as mild, moderate or severe according to postoperative HSA.ResultsMean and SD values for the change in HSA were 3,7 degrees (5,0 degrees), for 3-point alpha-angle 6,8 degrees (8,9 degrees), and anatomic alpha-angle 13,0 degrees (16,3 degrees). The overall increase in AOR was 0,038 (0.069). There were no significant differences between the slip severity groups.ConclusionsWe found limited angular remodelling after in situ fixation with smooth pins or short threaded screws for SCFE. The angular remodelling and the reduction of the CAM deformity was less than previously described after fixation of SCFE with similar implants. Results about the same magnitude with non-growth sparing techniques suggest that factors other than longitudinal growth of the femoral neck are important for angular remodelling.

Background This cross-sectional study aimed to examine whether appraisal of knee function, psychological and demographic factors were related to returning to the preinjury sport and recreational activity following anterior cruciate ligament (ACL) reconstruction. Method 164 participants completed a questionnaire battery at 1-7 years after primary ACL reconstruction. The battery included questionnaires evaluating knee self-efficacy, health locus of control, psychological readiness to return to sport and recreational activity, and fear of reinjury; and self-reported knee function in sport-specific tasks, knee-related quality of life and satisfaction with knee function. The primary outcome was returning to the preinjury sport or recreational activity. Results At follow-up, 40% (66/164) had returned to their preinjury activity. Those who returned had more positive psychological responses, reported better knee function in sport and recreational activities, perceived a higher knee-related quality of life and were more satisfied with their current knee function. The main reasons for not returning were not trusting the knee (28%), fear of a new injury (24%) and poor knee function (22%). Psychological readiness to return to sport and recreational activity, measured with the ACL-Return to Sport after Injury scale (was most strongly associated with returning to the preinjury activity). Age, sex and preinjury activity level were not related. Conclusions Less than 50% returned to their preinjury sport or recreational activity after ACL reconstruction. Psychological readiness to return to sport and recreation was the factor most strongly associated with returning to the preinjury activity. Including interventions aimed at improving this in postoperative rehabilitation programmes could be warranted to improve the rate of return to sport and recreational activities.

When stress fractures started to show up in the femurs of elderly ladies, it was soon evident that bisphosphonate use lay behind, and the absolute risk increase due to bisphosphonate use was reasonably well estimated already in 2008. Thereafter followed a period of confusion: the term atypical fracture was introduced, with a definition so vague that the true stress fractures tended to disappear in a cloud of ambiguity. This cast doubt on the association with bisphosphonates. The association was then re-established by large epidemiological studies based on radiographic adjudication. Atypical fractures are largely caused by bisphosphonates. With a correct indication, bisphosphonates prevent many more fractures than they cause, at least during the first years of use. With an incorrect indication they are likely to cause more harm than good. (C) 2016 Elsevier Ltd. All rights reserved.

[No abstract available]

Degradable screws and plates for bone surgery have been produced from silk protein. The idea is to eliminate the need to take the implant out when the bone has healed. Will they provide sufficient strength, and will they degrade without causing inflammation? And why take implants out in the first place?

Background: Osteoporosis drugs might affect fracture-healing. We therefore studied the effects of teriparatide in comparison with risedronate on recovery after pertrochanteric hip fractures. Methods: The study was a randomized, multicenter, active-controlled, 78-week trial comparing teriparatide (20 mg/day) with risedronate (35 mg/week) initiated within 2 weeks after fixation of a low-trauma pertrochanteric hip fracture (AO/OTA 31-A1 or 31-A2). The main inclusion criteria were a bone mineral density T-score of amp;lt;=-22.0 and 25-OH-vitamin D of amp;gt;= 9.2 ng/mL. During the first 26 weeks, patients received study medication with oral or injectable placebo plus calcium and vitamin D in a double-blinded fashion. Secondary (Timed Up-and-Go [TUG] test, hip pain, Short Form [SF]-36 health status, and safety) and exploratory (radiographic outcomes and ability to walk) 26-week end points are reported. Results: Of the 224 patients who were randomized, 171 (86 teriparatide, 85 risedronate) were included in the analysis. The mean age was 77 +/- 8 years, 77% were female, and 26% had a prior history of low-trauma fracture. The teriparatide group completed the TUG test in a shorter time at 6, 12, 18, and 26 weeks (differences of 25.7, -4.4, -3.1, and -3.1 seconds, respectively; p = 0.021 for the overall difference). They also reported less pain on a visual analog scale immediately after the TUG test at 12 and 18 weeks (adjusted absolute differences of 10.6 and 11.9 mm, respectively; p amp;lt; 0.05). There were no significant between-group differences in the SF-36 score, Charnley hip pain score, ability to walk, or use of walking aids during follow-up. Radiographic healing at 6, 12, and 26 weeks, mechanical failure of the implant (teriparatide, 7; risedronate, 8), loss of reduction (teriparatide, 2; risedronate, 4), and nonunion (0 cases) were not significantly different. Mild hypercalcemia and hyperuricemia were more frequent with teriparatide. Conclusions: Teriparatide was associated with less pain and a shorter time to complete the TUG test between 6 and 26 weeks compared with risedronate. Other fracture-recovery outcomes were similar. The results should be interpreted with caution as these were secondary end points.

Background: healing after rupture of the Achilles tendon can be described in terms of mechanical properties of the new-formed tissue, constituting the tendon callus. In previous human studies, the elastic modulus and the density remained almost constant during 3 months after mobilization started, and then improved up to one year. So far, time-dependent deformation of the healing human tendon has not been reported.

Methods: in a series of 16 patients, operated with Achilles tendon suture, we implanted tantalum beads into the tendon and measured the distance between them repeatedly during 3 min of constant loading, using an ordinary image intensifier. The patients unloaded their leg for 30 min before the test. To avoid bias, all images were investigated in a randomized and blinded order.

Results: total strain during 3 min of constant loading at 7 weeks post injury amounted to 5%, and at 19 weeks to 3%. About half of the strain, after the loading was applied, occurred during the second and third min. Considerable strain also occurred just before loading, when the patient was told that a load would be applied, but before this was actually done.

Conclusion: the measurements were crude, and this study should be seen as a pilot. Still, viscoelastic properties seem to dominate the mechanical behavior the healing Achilles tendon from start of mobilization to 19 weeks, at least when tested after 30 min rest. This deserves further studies with more precise methods.

Atypical fractures are stress fractures occurring in the femoral shaft and closely related to bisphosphonate use. We here discuss their radiographic definition and different putative etiologies, apart from mechanical stress. Long time reduction of skeletal remodeling because of bisphosphonate use is thought to allow time for the bone to deteriorate mechanically, resulting in reduced toughness. However, the risk of atypical fracture diminishes rapidly after cessation of treatment, which suggests more acute effects of bisphosphonate use. Microdamage normally accumulates at areas of high stress. Possibly, ongoing bisphosphonate use reduces the ability to resorb and replace areas of microdamage by targeted remodeling. This could lead to crack propagation beyond a point of no return, ending in macroscopic stress fracture.

Stress fractures are caused by material fatigue. Microcracks appear normally in bone, and are dealt with by remodeling, specifically targeting areas of microdamage. Inhibition of targeted remodeling can allow microcracks to grow and form fractures. Intensive athletic training can lead to an increased microcrack formation rate, which exceeds what can be balanced by remodeling. Stress fractures often heal poorly, possibly because they are so thin: normal deformation of the bone during loading has been shown to lead to strains within thin cracks that are incompatible with cell survival. If the patient can't reduce loading sufficiently to allow healing, surgical stabilization will therefore be required. If the crack is transformed into a larger defect, e.g. by drilling a hole, strains will be reduced and healing facilitated by a simple procedure.

Purpose: To analyze and compare clinical outcomes after anterior cruciate ligament (ACL) reconstruction 5 and 10 years postsurgery between patients with concomitant intra-articular injuries and those with isolated ACL injury at reconstruction. Methods: Registrations were made using a web-based protocol by physicians for baseline and surgical data. Patients registered their Knee Injury and Osteoarthritis Outcome Score (KOOS) preoperatively and at 5 and 10 years postsurgery. The exclusion criteria for the present study were revisions of previously unregistered ACL surgeries, non-ACL surgeries, patients for whom 10-year follow-up data had not yet been collected, and the proportion of index surgeries that were revision or contralateral interventions. Results: There were 1,295 KOOS scores available for patients 5 years postsurgery, and 1,023 10 years postsurgery from a baseline of 2,751 index reconstructions. A deterioration between the 5-and 10-year scores was observed for patients with concomitant meniscus injury on the KOOS subscales for pain (P = .015), symptoms (P = .005), sport and recreation (P = .011), and knee-related quality of life (QoL) (P = .03) compared with patients with isolated ACL injury. Correspondingly, KOOS subscale score deterioration was seen for combined concomitant cartilage and meniscus injuries for pain (P = .005), symptoms (P = .009), sport and recreation (P = .006), and QoL (P amp;lt; .001). The largest deteriorations were found in sport and recreation (-5.9 points; confidence interval [CI] -10.1, -1.1) and QoL (-6.5 points; CI -10.3, -2.8) subscale scores for patients with concomitant meniscal and cartilage injuries. A similar pattern was not seen between patients with concomitant cartilage injury and isolated ACL injury. Conclusions: The present study reveals that concomitant meniscus injuries at the index operation, either in isolation or in combination with cartilage lesions, render a deterioration of scores on the KOOS outcome subscales for pain, sport and recreation, and quality of life between 5-and 10-year postsurgery follow-up of ACL-reconstructed patients. No such deterioration was seen for patients who had isolated ACL injury.

The SummaryThis study examined the imminent risk of a future fracture within 1 and 2years following a first fracture in women aged 50years and older and assessed independent factors associated with risk of subsequent fractures. The study highlights the need to intervene rapidly after a fracture to prevent further fractures.IntroductionThis study aims to determine the imminent risk of subsequent fractures within 1 and 2years following a first fracture and to assess independent factors associated with subsequent fractures.MethodsRetrospective, observational cohort study of women aged 50years with a fragility fracture was identified from Swedish national registers. Clinical/demographic characteristics at the time of index fracture and cumulative fracture incidences up to 12 and 24months following index fracture were calculated. Risk factors for subsequent fracture were identified using multivariate regression analysis.ResultsTwo hundred forty-two thousand one hundred eight women (mean [SD] age 74 [12.5] years) were included. The cumulative subsequent fracture incidence at 12months was 7.1% (95% confidence interval [CI], 6.9-7.2) and at 24months was 12.0% (95% CI, 11.8-12.1). The rate of subsequent fractures was highest in the first month (similar to 15 fractures per 1000 patient-years) and remained steady between 4 and 24months (similar to 5 fractures/1000 patient-years). Higher age was an independent risk factor for imminent subsequent fractures (at 24months, sub-distribution hazard ratio [HR], 3.07; pamp;lt;0.001 for women 80-89years [reference 50-59years]). Index vertebral fracture was a strong independent risk factor for subsequent fracture (sub-distribution HR, 2.72 versus hip fracture; pamp;lt;0.001 over 12months; HR, 2.23; pamp;lt;0.001 over 24months).ConclusionsOur findings highlight the need to intervene rapidly after any fragility fracture in postmenopausal women. The occurrence of a fragility fracture provides healthcare systems with a unique opportunity to intervene to reduce the increased risk of subsequent fractures.

Bone mineral density (BMD) is an established measure used to diagnose patients with osteoporosis. In clinical trials, change in BMD has been shown to provide a reliable estimate of fracture risk reduction, and achieved BMD T-score has been shown to reflect the near-term risk of fracture. We aimed to test the association between BMD T-score and fracture risk in patients treated for osteoporosis in a real-world setting. This retrospective, observational cohort study included Swedish females aged &gt;= 55 years who had a total hip BMD measurement at one of three participating clinics. Patients were separated into two cohorts: bisphosphonate-treated and bisphosphonate-naive prior to BMD measurement, stratified by age and prior nonvertebral fracture status. The primary outcome was cumulative incidence of clinical fractures within 24 months of BMD measurement, with other fracture types included as secondary outcomes. Associations between T-score and fracture risk were estimated using proportional hazards regression and restricted cubic splines. A total of 15,395 patients were analyzed: 11,973 bisphosphonate-naive and 3422 bisphosphonate-treated. In the 24 months following BMD measurement, 6.3% (95% confidence interval [CI], 5.9-6.7) of bisphosphonate-naive and 8.4% (95% CI, 7.5-9.4) of bisphosphonate-treated patients experienced a clinical fracture. Strong inverse relationships between BMD T-score and fracture incidence were observed in both cohorts. Among bisphosphonate-naive patients, this relationship appeared to plateau around T-score -1.5, indicating smaller marginal reductions in fracture risk above this value; bisphosphonate-treated patients showed a more consistent marginal change in fracture risk across the evaluated T-scores (-3.0 to -0.5). Trends remained robust regardless of age and prior fracture status. This real-world demonstration of a BMD-fracture risk association in both bisphosphonate-naive and bisphosphonate-treated patients extends evidence from clinical trials and recent meta-regressions supporting the suitability of total hip BMD as a meaningful outcome for the clinical management of patients with osteoporosis. (c) 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Background We have previously reported inconclusive results from a randomized controlled trial in elderly with hip-fracture comparing intra-operative goal-directed therapy with routine fluid treatment. Now we aimed to describe and compare secondary outcomes at 4 months and 1 year follow-up and to analyze the cost-effectiveness. Methods Patients with hip fracture (age amp;gt;= 70) were randomized for GDT or routine fluid treatment (RFT). The secondary outcomes were long-term survival, complications, number of hospital readmissions, and quality of life (EQ-5D) changes. Additionally, cost effectiveness was analyzed by an analytic tool which combines the clinical effectiveness, quality of life changes and costs. Results Patient data (GDT n = 74; RFT n = 75) were analyzed on an intention to treat basis. Statistically significant differences (GDT vs RFT) were not found considering survival (RR 0.76, 95%CI 0.45-1.28) and complications (RR 0.68, 95% CI 0.4-1.10) at 12 months. No statistically significant difference was found between hospital readmissions and quality of life changes. Conclusion The statistical uncertainty of risk reduction of negative outcomes and the large variability of the collected data indicate the need of further research in large sample sizes. To enable future health economic evaluation for decision support surrounding implementation of GDT, we suggest adding patient-oriented outcomes in future trials.

Background: Roux-en-Y gastric bypass (RYGB) among adolescents with obesity results in signif-icant weight loss; however, depot-specific changes have been understudied.Objective: We hypothesized that visceral adipose tissue (VAT) reduction in adolescents undergoing RYGB would be greater than other depots and associated with improvement in cardiometabolic risk factors.Setting: Three specialized treatment centers in Sweden. Methods: Fifty-nine adolescents underwent dual x-ray absorptiometry before surgery and at 1, 2, and 5 years after RYGB. Changes in body composition in multiple depots (total fat, lean body, gynoid fat, android fat, subcutaneous adipose tissue, and VAT) and cardiometabolic risk factors were assessed using multiple linear regression analysis and generalized estimating equations adjusting for age, sex, and baseline risk factor levels. Data are presented as percent change (95% CI) with regression models showing slopes and estimated P values.Results: At 1 year post-RYGB, a significant reduction was observed across all body composition measures (P , .001) with the greatest reduction observed in VAT (-65.1% [-68.7, -61.8]). From year 1 to 5 years post-RYGB, a regain was observed in all depots except lean body mass (1.2% [.3, 2.7], P 5 .105). A sex-specific difference in overall trajectories was only observed in lean body mass with males consistently having higher mean levels. Change in VAT at 1 year correlated with change in triglycerides (slope: .21 mg/dL/kg, P = .034) and fasting plasma insulin (slope: 44 pmol/L/kg, P = .027). Conclusions: Adiposity measures all decreased after RYGB but poorly predicted change in cardio-metabolic risk. Despite significant reductions at 1 year, a steady regain was observed out to 5 years, with values still well below baseline. Further research should consider control group comparison and extended follow-up.

Local delivery of antibiotics as prophylaxis for prosthetic joint infections (PJIs) is frequently used during total hip replacement surgery. Morselized bone allograft impregnated with vancomycin and tobramycin (TobraVanc) could provide effective prophylaxis against bacteria commonly associated with PJIs. In this study, the concentrations of antibiotics released by bone allograft impregnated with TobraVanc were determined by using an in vitro bioassay system entailing measuring inhibition zone diameters caused by antibiotic-impregnated bone chips cast in agar against standard curves. The concentrations were determined in samples of TobraVanc-impregnated bone graft taken before and after the application of the bone graft in the patients undergoing acetabular revision surgery. Antibiotic-impregnated bone grafts, sampled prior to application in the patient, delivered antibiotics in the concentration ranges of 730-9,800 mg/L for tobramycin and 1,300-11,000 mg/L for vancomycin. Samples taken after application in the patient released lower concentrations of tobramycin (490-1,900 mg/L; P &lt; 0.01) and vancomycin (3,000-5,100 mg/L; P &lt; 0.05); however, these concentrations remained well above the tobramycin minimum inhibitory concentrations (MICs) for investigated, highly tobramycin-resistant Staphylococcus epidermidis strains (MICs &gt; 256 mg/L). At the tested concentrations, bone graft material mixed with TobraVanc delivered antibiotics in potent concentrations above the MICs for bacteria causing PJIs. Clinical trials are needed to evaluate the efficacy and risk of TobraVanc-impregnated bone graft as a prophylactic agent for patients undergoing hip replacement surgery.

Objective. Primary chronic osteomyelitis (PCO) of the jaws in children is associated with pain, trismus, and swelling. In children, temporomandibular joint involvement is rare and few studies have been published due to the relatively low incidence. This paper presents two cases of mandibular PCO in children with the involvement of the collum mandibulae. In addition, a review of the literature regarding demographic data, histological, radiological, and laboratory findings, and treatment strategies of PCO was also performed. Material and Methods. Prospective analyses of two PCO cases. A PubMed search was used and the articles were sorted according to their corresponding key area of focus. Results. Review of the literature revealed twenty-four cases of PCO with two cases of mandibular condyle involvement. The mean age was 18 years; the male to female ratio was 1 : 3. Most of the patients were treated with anti-inflammatory drugs in combination with decortication. Clinical recurrence was seen in 7 cases. Conclusion. A combination of anti-inflammatory drugs and surgical intervention appears to be the first choice of treatment. However, surgical removal of necrotic tissue adjacent to collum mandibulae has its limitations in children. Further investigations are of utmost importance in order to increase our knowledge and understanding of this disease.

Most of what is known about the biological response during fracture healing comes from numerous animal studies with shaft fractures in the long bone. However, most patients suffer from fractures closer to the ends of the long bones, in the hip, or in the vertebrae. These types of fractures mainly involve cancellous bone, while shaft fractures concern cortical bone. Compared to cortical bone whose structure is dense and compact, cancellous bone is of spongy and porous structure. A growing number of studies point towards that cortical and cancellous bone heal differently. To even this imbalance in knowledge between these two types of bone tissue, further studies in cancellous bone are justified.

In this thesis we delved into the quiet unknown processes behind cancellous bone healing.

In the first study we characterized and compared two models for cancellous bone healing in mice and rats: the first model can be used to analyze the morphology and morphometry of the regenerating bone; the second model can measure the mechanical properties of cancellous bone. The two models correspond in their developing patterns during the first week before they diverge. This suggests that these models can be utilized together to evaluate the initial healing in cancellous bone. Furthermore, we saw in the drill hole model that the bone formation is strictly restricted to the traumatized region, with a distinct interface to the adjacent uninjured tissue.

The second study characterized the cellular response during the initial healing phase in cancellous bone. The focus was to follow the spatial location of inflammatory and osteogenic cells over time in a cancellous bone injury. In contrast to shaft fractures (cortical bone), where healing is described as sequential events where inflammatory cells are the first to arrive to the trauma before osteogenic cells are recruited and initiate healing, we could see how inflammatory and osteogenic cells appeared early, simultaneously after a cancellous bone injury. This study showed that cancellous bone differs from how fracture healing is normally described.

In the third study we explored the role of a subpopulation of lymphocytes (CD8 positive cells), earlier studied in shaft fractures. We wanted to see how their absence would affect the healing in a cancellous bone injury. Without CD8⁺ cells, cancellous bone healing was impaired as expressed via poorer mechanical properties of the regenerated bone tissue.

The fourth and last study issued the influence of uninjured bone marrow on cortical bone healing. We developed a cortical defect model which blocked uninjured marrow from reaching the defect. Without the presence of marrow, the cortical defects ability to regenerate was significantly impaired. This implies that the marrow is important for cortical bone healing.

In conclusion, cancellous bone healing is different from its cortical counterpart and the general perception of fracture healing. We have briefly discerned healing mechanisms in cancellous bone that might be of clinical importance: the restricted cancellous bone formation is something to take into consideration when performing arthrodeses; and importance of marrow in skeletal defects (e.g. pseudarthroses). With this thesis, we hope to promote that further investigating on cancellous bone healing is necessary.

Background and purpose - Teriparatide accelerates fracture healing in animals and probably in man. Abaloparatide is a new drug with similar although not identical effects on the teriparatide receptor. Given at 4 times the teriparatide dose in a human osteoporosis trial, abaloparatide increased bone density more than teriparatide, and both reduced fracture risk. We investigated in mice whether abaloparatide stimulates fracture healing, and if it does so with the suggested dose effect relation (4:1). Patients and methods - In a validated mouse model for metaphyseal healing (burr hole with screw pull-out), 96 mice were randomly allocated to 11 groups: control (saline), teriparatide or abaloparatide, where teriparatide and abaloparatide were given at 5 different doses each. In a femoral shaft osteotomy model, 24 mice were randomly allocated to 3 groups: control (saline), teriparatide (15 mu g/kg) or abaloparatide (60 mu g/kg). Each treatment was given daily via subcutaneous injections. Results were evaluated by mechanical testing and microCT. Results - In the metaphyseal model, a dose-dependent increase in screw pull-out force could be seen. In a linear regression analysis (r = 0.78) each increase in ln(dose) by 1 (regardless of drug type) was associated with an increase in pull-out force by 1.50 N (SE 0.18) (p amp;lt; 0.001). Changing drug from teriparatide to abaloparatide increased the force by 1.41 N (SE 0.60; p = 0.02). In the diaphyseal model, the callus density was 23% (SD 10), 38% (SD 10), and 47% (SD 2) for control, for teriparatide and abaloparatide respectively. Both drugs were significantly different from controls (p = 0.001 and p = 0.008), but not from each other. Interpretation - Both drugs improve fracture healing, but in these mouse models, the potency per mu g of abaloparatide seems only 2.5 times that of teriparatide, rather than the 4:1 relation chosen in the clinical abaloparatide-teriparatide comparison trial.

Background and purpose - Fracture healing in the shaft is usually described as a sequence of events, starting with inflammation, which triggers mesenchymal tissue formation in successive steps. Most clinical fractures engage cancellous bone. We here describe fracture healing in cancellous bone, focusing on the timing of inflammatory and mesenchymal cell type appearance at the site of injury. Material and methods - Rats received a proximal tibial drill hole, A subgroup received clodronate-containing liposomes before or after surgery. The tibiae were analyzed with micro-CT and immunohistochemistry 1 to 7 days after injury. Results - Granulocytes (myeloperoxidase) appeared in moderate numbers within the hole at day 1 and then gradually disappeared. Macrophage expression (CD68) was seen on day 1, increased until day 3, and then decreased. Mesenchymal cells (vimentin) had already accumulated in the periphery of the hole on day 1. Mesenchymal cells dominated in the entire lesion on day 3, now producing extracellular matrix. A modest number of preosteoblasts (RUNX2) were seen on day 1 and peaked on day 4. Osteoid was seen on day 4 in the traumatized region, with a distinct border to the uninjured surrounding marrow. Clodronate liposomes given before the injury reduced the volume of bone formation at day 7, but no reduction in macrophage numbers could be detected. Interpretation - The typical sequence of events in shaft fractures was not seen. Mesenchymal cells appeared simultaneously with granulocyte and macrophage arrival. Clodronate liposomes, known to reduce macrophage numbers, seemed to be associated with the delineation of the volume of tissue to be replaced by bone.

As cytotoxic (CD8(+)) T cells seem to impair shaft fracture healing, we hypothesized that depletion of CD8(+) cells would instead improve healing of cancellous bone. Additionally, we also tested if CD8-depletion would influence the healing of ruptured Achilles tendons. Rats received a single injection of either anti-CD8 antibodies or saline and put through surgery 24 h later. Three different surgical interventions were performed as follows: (1) a drill hole in the proximal tibia with microCT (BV/TV) to assess bone formation; (2) a screw in the proximal tibia with mechanical evaluation (pull-out force) to assess fracture healing; (3) Achilles tendon transection with mechanical evaluation (force-at-failure) to assess tendon healing. Furthermore, CD8-depletion was confirmed with flow cytometry on peripheral blood. Flow cytometric analysis confirmed depletion of CD8(+) cells (p amp;lt; 0.001). Contrary to our hypothesis, depletion of CD8(+) cells reduced the implant pull-out force by 19% (p amp;lt; 0.05) and stiffness by 34% (p amp;lt; 0.01), although the bone formation in the drill holes was the same as in the controls. Tendon healing was unaffected by CD8-depletion. Our results suggest that CD8(+) cells have an important part in cancellous bone healing.

Background and purpose — [18F]Fluoride ([18F]NaF) PET scan is frequently used for estimation of bone healing rate and extent in cases of bone allografting and fracture healing. Some authors claim that [18F]NaF uptake is a measure of osteoblastic activity, calcium metabolism, or bone turnover. Based on the known affinity of fluoride to hydroxyapatite, we challenged this view.

Methods — 10 male rats received crushed, frozen allogeneic cortical bone fragments in a pouch in the abdominal wall on the right side, and hydroxyapatite granules on left side. [18F]NaF was injected intravenously after 7 days. 60 minutes later, the rats were killed and [18F]NaF uptake was visualized in a PET/CT scanner. Specimens were retrieved for micro CT and histology.

Results — MicroCT and histology showed no signs of new bone at the implant sites. Still, the implants showed a very high [18F]NaF uptake, on a par with the most actively growing and remodeling sites around the knee joint.

Interpretation — [18F]NaF binds with high affinity to dead bone and calcium phosphate materials. Hence, an [18F]NaF PET/CT scan does not allow for sound conclusions about new bone ingrowth into bone allograft, healing activity in long bone shaft fractures with necrotic fragments, or remodeling around calcium phosphate coated prostheses

Background and purpose - Healing of shaft fractures is commonly described as regards external callus. We wanted to clarify the role of the bone marrow compartment in the healing of stable shaft fractures. Patients and methods - A longitudinal furrow was milled along the longitudinal axis of the femoral shaft in mice. The exposed bone marrow under the furrow was scooped out. The mice were then randomized to no further treatment, or to receiving 2 silicone plugs in the medullary canal distal and proximal to the defect. The plugs isolated the remaining marrow from contact with the defect. Results were studied with histology and flow cytometry. Results - Without silicone plugs, the marrow defect was filled with new bone marrow-like tissue by day 5, and new bone was seen already on day 10. The new bone was seen only at the level of the cortical injury, where it seemed to form simultaneously in the entire region of the removed cortex. The new bone seemed not to invade the marrow compartment, and there was a sharp edge between new bone and marrow. The regenerated marrow was similar to uninjured marrow, but contained considerably more cells. In the specimens with plugs, the marrow compartment was either filled with loose scar tissue, or empty, and there was only minimal bone formation, mainly located around the edges of the cortical injury. Interpretation - Marrow regeneration in the defect seemed to be a prerequisite for normal cortical healing. Shaft fracture treatment should perhaps pay more attention to the local bone marrow.

Purpose The critical shoulder angle (CSA) and the acromion index (AI) are measurements of acromial shape reported as predictors of degenerative rotator cuff tears (RCT) and glenohumeral osteoarthritis (GH OA). Whether they are the cause or effect of shoulder pathologies is uncertain since pre-morbid radiographs most often are lacking. The main aim of this study was to investigate if CSA or AI were related to the development of RCT or GH OA after 20 years. A secondary aim was to investigate if the CSA and AI had changed over time. Methods In the hospital archive, 273 preoperative plain shoulder radiographs were found of patients scheduled for elective surgery other than cuff repair and arthroplasty. Forty-five images fulfilled the strict criteria published by Suter and Henninger (2015) and were used to measure CSA and AI with two independent assessors. No patient had any sign of OA in the index radiographs or any information in the medical records indicating RCT. After a median of 20 (16-22) years, 30 of these patients were radiologically re-examined with bilateral true frontal views and ultrasound of the rotator cuff. There were 19 men (20 study shoulders) and 11 females (12 study shoulders). Results Mean age at follow-up was 56 (32-78) years. There was no correlation between CSA (r = 0.02) (n.s) or AI (r = - 0.13) (n.s) in the primary radiographs and OA at follow-up. Nor was any correlation found between index CSA (r = 0.12) (n.s) or AI (r = - 0.13) (n.s) and RCT at follow-up. Mean difference in CSA was - 1.7 (- 10-3) degrees and mean AI difference was - 0.04 (- 0.13-0.09) between the first and the second radiographs, 20 years later. Bilaterally, mean CSA was 32 and AI 0.61 at follow-up. Conclusion In this study, no correlation between the CSA, AI and development of OA or RCT could be found. The mean CSA and AI decreased over a 20-year period but the difference was very small. No difference was found between the study shoulders and the contralaterals. These findings question previously reported etiological associations between scapular anatomy and the development of OA or RCT and thereby the use of these calculations as the basis of treatment.

Background and purpose:Extracellular matrix remodelling is altered in rotator cuff tears,16partly due to altered expression of matrix metalloproteinases (MMPs) and their inhibitors. It is unclear if this altered expression can be traced as changes in plasma protein levels.

The purposes were to measure the plasma level of MMPs and their tissue inhibitors (TIMPs) inpatients with rotator cuff tears and to relate changes in the pattern of MMP and TIMP levels with the extent of the rotator cuff tear.

Methods: Blood samples were collected from 17 patients, median 61 (range 39-77) years, with sonographically verified rotator cuff tears (partial- or full-thickness). These were compared with 16 gender and age matched control persons with sonographically intact rotator cuffs. Plasma levels of MMPs and TIMPs were measured simultaneously using Luminex technology and ELISA.

Results: The plasma level of TIMP-1 was elevated in patients with rotator cuff tears, especially in those with full-thickness tears. The levels of TIMP-1, TIMP-3 and MMP-9 were higher in patients with full-thickness tears compared to those with partial-thickness tears, but only TIMP-1 was different from controls.

Interpretation: The observed elevation of TIMP-1 in plasma might reflect local pathological processes in or around the rotator cuff, or a genetic predisposition in these patients. That levels of TIMP-1 and certain MMP´s was found to differ between partial and full thickness tears may reflect the extent of the lesion or different aetiology and pathomechanisms.

Background: A specific exercise strategy focusing on eccentric exercises, for treating sbacromial pain has in a previous study been found effective at three-month followup.

The aim of the present study was to investigate if the positive short-term results were maintained after one year. A further aim was to examine if baseline clinical score, rotator cuff status and radiological findings influenced the choice of surgery.

Methods: 97 patients on the waiting-list for arthroscopic subacromial decompression were in the first study randomized to a three-month specific exercise strategy or unspecific exercises (controls). Patients were examined with radiology, ultrasound and assessed with clinical scores: primary Constant-Murley score. After three months of exercises the patients were asked if they still wanted surgery and this option was available until the one-year follow-up. All patients were re-assessed with clinical scores one year after inclusion or one year after surgical intervention and the number of patients that had chosen surgery in each group was compared. The baseline Constant-Murley score and the status of subacromial structures were analyzed in relation to patient's choice of surgery.

Results: The positive short-term effect (improved shoulder function and pain) of the specific exercises was maintained after one-year. Compared to the three-month followup all patients had improved significantly (p < 0.0001) in Constant-Murley score. The number of patients that had chosen surgery in the control exercise group (63%) was significantly larger (p < 0.0001) than in the specific exercise group (24%). Patients that had chosen surgery had a significantly lower baseline Constant-Murley score and significantly more often a full-thickness tear. Patients with partial-thickness tears did not differ from those with intact cuff tendons.

Conclusions: The positive short-term outcomes after specific exercises were maintained after one year and reduced the need of surgery significantly more than the unspecific control exercises. Patients with low baseline clinical score and/or a full-thickness tear significantly more often chose surgery.

Level of evidence: I, Randomized controlled trail according to Consort statement.

Background. Macrophages are a heterogeneous cell population that plays an important role in the initiation of the inflammatory response to trauma as well as its resolution during healing. However, their role during Achilles tendon healing is unclear. The aim of this study was to investigate if macrophage reduction by using clodronate liposome inject ion would influence the mechanical properties of the healing tendon. Methods. The right Achilles tendon of 46 rats were transected and left to heal spontaneously (day 0). The reduction of macrophages during the inflammatory phase of tendon healing was studied by injecting clodronate liposomes day - 3, - 1 and 1. To study the early remodeling phase, clodronate was injected day 3, 5 and 7. The controls received saline and the rats were evaluated by mechanical testing day 7 and 12, respectively. Results. Clodronate injections during the inflammatory phase increased transverse area (p = 0.006) and stiffness (p = 0.044) day 7. In contrast, no significant effects were seen at day 12. Flow cytometry evaluation confirmed reduction of mature and polarized macrophages. Conclusions. Reduction of macrophages during the inflammatory phase of Achilles tendon healing influenced the mechanical properties, suggesting a regulatory role of macrophages during this phase.

We excised the fracture site in 8 patients with incomplete atypical femoral fractures by drilling an 11-mmdiameter hole. New bone formation could be seen in the hole within a normal time frame. Delayed healing of these fractures might be unrelated to an impaired capacity to form bone. Introduction Incomplete atypical femoral fractures (undisplaced cracks) heal slowly or not at all, and often progress to a complete fracture with minimal trauma. The impaired healing has been attributed to an impaired biologic healing capacity related to bisphosphonate use, or, alternatively, to the mechanical environment within the fracture crack. This study aimed to investigate the capacity for bone formation after resection of the fracture site. Methods Between 2008 and 2014, we recruited eight patients with incomplete atypical femoral fractures. All used oral bisphosphonates before the fracture for on average 8 years (range 4 to 15) and complained of thigh pain. The fractures were stabilized with reamed cephalomedullary nails. During surgery, the fracture site in the lateral cortex was resected with a cylindrical drill (diameter 11.5 mm). The cylindrical cortical defect allowed radiographic evaluation of new bone formation, and the patients were followed clinically and radiologically for 24 months (range 15 to 92). Results After 3 months, newly formed bone could be seen in the cortical defects in all patients. After 13-26 months, the previous defects showed continuous cortical bone. At final follow-up, all patients reported full recovery of pre-surgical complaints. No complications occurred and no reoperations were performed. Conclusions New bone formation occurred within a time frame that appears normal for healing of cortical bone defects. This suggests that the capacity to form new bone is intact.

BackgroundDespite its well-established positive effects, exercise-based cardiac rehabilitation (exCR) is underused in patients following an acute myocardial infarction (AMI). The aim of the study was to identify factors associated with non-attendance at exCR in patients post-AMI in a large Swedish cohort.MethodsA total of 31,297 patients who have suffered an AMI, mean age 62.44years, were included from the SWEDEHEART registry during the years 2010-2016. Comparisons between attenders and non-attenders at exCR were done at baseline for the following variables: age, sex, body mass index, occupational status, smoking, previous diseases, type of index cardiac event and intervention, and left ventricular function. Distance of residence from the hospital and type of hospital were added as structural variables in logistic regression analyses, with non-attendance at exCR at one-year follow-up as dependent, and with individual and structural variables as independent variables.ResultsIn total, 16,214 (52%) of the patients did not attend exCR. The strongest predictor for non-attendance was distance to the exCR centre (OR 1.75 [95% CI: 1.64-1.86]). Other predictors for non-attendance included smoking, history of stroke, percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), AMI or diabetes, male sex, being retired vs. being employed, and being followed-up at a county hospital. Patients with ST-elevation myocardial infarction (STEMI) and those intervened with PCI or CABG were more likely to attend exCR.Conclusions A distance greater than 16km was associated with increased probability of non-attendance at exCR, as were smoking, a higher burden of comorbidities, and male sex. A better understanding of individual and structural factors can support the development of future rehabilitation services.

BackgroundInterventions promoting adherence to exercise-based cardiac rehabilitation (exCR) are important to achieve positive physical and psychological outcomes, but knowledge of the added value of behavioral medicine interventions for these measures is limited. The aim of the study was to investigate the added value of a behavioral medicine intervention in physical therapy (BMIP) in routine exCR on psychological outcomes and health-related quality of life (HRQoL) versus routine exCR alone (RC).MethodsA total of 170 patients with coronary artery disease (136 men), mean age 62.3 +/- 7.9 years, were randomized at a Swedish university hospital to a BMIP plus routine exCR or to RC for four months. The outcome assessments included HRQoL (SF-36, EQ-5D), anxiety and depression (HADS), patient enablement and self-efficacy and was performed at baseline, four and 12 months. Between-group differences were tested with an independent samples t-test and, for comparisons within groups, a paired t-test was used. An intention-to-treat and a per-protocol analysis were performed.ResultsNo significant differences in outcomes between the groups were shown between baseline and four months or between four and 12 months. Both groups improved in most SF-36 domains, EQ-VAS and HADS anxiety at the four-month follow-up and sufficient enablement remained at the 12-months follow-up.ConclusionA BMIP added to routine exCR care had no significant effect on psychological outcomes and HRQoL compared with RC, but significant improvements in several measures were shown in both groups at the four-month follow-up. Since recruited participants showed a better psychological profile than the general coronary artery disease population, further studies on BMIP in exCR, tailored to meet individual needs in broader patient groups, are needed.Trial registration number NCT02895451, 09/09/2016, retrospectively registered.

Introduction In Sweden, roughly 3000 patients are reoperated each year due to pain and loss of function related to a loosened hip or knee prosthesis. These reoperations are strenuous for the patient, technically demanding and costly for the healthcare system. Any such reoperation that can be prevented would be of great benefit. Bisphosphonates are drugs that inhibit osteoclast function. Several clinical trials suggest that bisphosphonates lead to improved implant fixation and one small study even indicates better functional outcome. Furthermore, in epidemiological studies, bisphosphonates have been shown to decrease the rate of revision for aseptic loosening by half. Thus, there are several indirect indications that bisphosphonates could improve patient-reported outcome, but no firm evidence. Methods and analysis This is a pragmatic randomised, placebo-controlled, double-blinded, academic clinical trial of a single postoperative dose of zoledronic acid, in patients younger than 80 years undergoing primary total hip or knee replacement for osteoarthritis. Participants will be recruited from two orthopaedic departments. All surgeries will be performed, and study drugs given at Motala Hospital, Sweden. The primary endpoint is to investigate between-group differences in the Hip dysfunction and Osteoarthritis Outcome Score and the Knee injury and Osteoarthritis Outcome Score at 3-year follow-up. Secondary outcomes will be investigated at 1 year, 3 years and 6 years, and stratified for hip and knee implants. These secondary endpoints are supportive, exploratory or explanatory. A total of 1000 patients will be included in the study. Ethics and dissemination The study has been approved by the Regional Ethical Review Board in Linkoping (DNR 2015/286-31). The study will be reported in accordance with the Consolidated Standards of Reporting Trials statement for pharmacological trials. The results will be submitted for publication in peer-reviewed academic journals and disseminated to patient organisations and the media.

Background: Stable fixation of joint replacement implants is essential to achieve osseointegration in uncemented implants. In acetabular revisions, screws often need to be utilized in quadrants other than the historically so-called "safe" zones to attain sufficient stability. The primary aim of this study was to determine whether preoperative three-dimensional (3D) planning for acetabular revision surgery influences screw length, specifically in the superior pubic ramus (SPR). Methods: Between March 2017 and December 2021, 20 patients underwent preoperative twodimensional (2D) planning (2D group), and 30 patients underwent 3D planning following the implementation of a new 3D planning software into clinical practice in September 2019 (3D group). Two observers, blinded to the groups, measured the total screw length, screw penetration depth, and cup position on available postoperative computed tomography examinations. For statistical comparisons, the mean measurement from the 2 observers was used. Results: The median total screw lengths in the SPR were 16 mm in the 2D group and 25 mm in the 3D group (P = .004) and 40.5 mm compared with 50.5 mm in the ilium (P = .019). Median screw penetration depths in the SPR were 0 mm in the 2D group and 1.25 mm in the 3D group (P = .049). Conclusion: Longer screws were used in the SPR and ilium when preoperative 3D planning was conducted. Due to the study design, we were not able to evaluate whether longer screws lead to better fixation. Further studies are needed to elucidate this question. (c) 2024 The Authors. Published by Elsevier Inc. on behalf of The American Association of Hip and Knee Surgeons. This is an open access article under the CC BY license.

Purpose

The pelvic incidence (PI) is used to describe the sagittal spino-pelvic alignment. In previous studies, radiographs were used, leading to less accuracy in establishing the three-dimensional (3D) spino-pelvic parameters. The purpose of this study is to analyze the differences in the 3D sagittal spino-pelvic alignment in adolescent idiopathic scoliosis (AIS) subjects and non-scoliotic controls.

Methods

Thirty-seven female AIS patients that underwent preoperative supine low-dose computed tomography imaging of the spine, hips and pelvis as part of their general workup were included and compared to 44 non-scoliotic age-matched female controls. A previously validated computerized method was used to measure the PI in 3D, as the angle between the line orthogonal to the inclination of the sacral endplate and the line connecting the center of the sacral endplate with the hip axis.

Results

The PI was on average 46.8° ± 12.4° in AIS patients and 41.3° ± 11.4° in controls (p = 0.025), with a higher PI in Lenke type 5 curves (50.6° ± 16.2°) as compared to controls (p = 0.042), whereas the Lenke type 1 curves (45.9° ± 12.2°) did not differ from controls (p = 0.141).

Conclusion

Lenke type 5 curves show a significantly higher PI than controls, whereas the Lenke type 1 curves did not differ from controls. This suggests a role of pelvic morphology and spino-pelvic alignment in the pathogenesis of idiopathic scoliosis. Further longitudinal studies should explore the exact role of the PI in the initiation and progression of different AIS types.

We examined the learning curve of Motec total wrist arthroplasty (TWA) of six experienced surgeons in their first 30 cases. Three times more complications/revisions were encountered in the first half of the study compared with the second half. Motec TWA surgery should be concentrated in a smaller number of centres performing higher volumes.

Neuropatisk smärta orsakas definitionsmässigt av en skada eller sjukdom i det somatosensoriska nervsystemet. Långvarig postoperativ smärta (LPOS) är tämligen vanligt, framför allt efter ingrepp som exempelvis amputation, torakotomi, eller mastektomi. I många fall anses LPOS vara av neuropatisk karaktär, och den farmakologiska behandlingen utgår då i stor utsträckning från rekommendationerna för behandling av neuropatisk smärta, med fokus på vissa antidepressiva läkemedel (amitriptylin, duloxetin) och gabapentinoider (gabapentin, pregabalin). Topikal behandling med till exempel lidokainplåster kan vara av stort värde när smärtan utlöses av lätt beröring av huden (allodyni). Överlag bör stor försiktighet råda angående långtidsanvändning av opioider. Vid LPOS efter bukkirurgi bör man speciellt beakta opioidernas negativa effekter på tarmfunktionen, eftersom en ”ond cirkel” kan uppkomma mellan ökade doser opioider och ökad smärta. Komplext regionalt smärtsyndrom (CRPS) kan uppkomma i en extremitet efter trauma av lindrig karaktär och/eller immobilisering (till exempel gipsning). Även om CRPS typ 1 definitionsmässigt inte är ett neuropatiskt smärttillstånd, är de farmakologiska behandlingsprinciperna ändå i stor utsträckning desamma som för neuropatisk smärta. Mer forskning behövs för att på sikt kunna få fram bättre, mer mekanism-baserade behandlingsmetoder.

Atypical femoral fractures are stress fractures of the femoral subtrochanteric and diaphyseal region. It is a common notion that these fractures heal poorly, if at all. In this thesis we show that patients with atypical femoral fractures have a good capacity to generate bone and therefore heal fractures. In daily practice, these patients have a higher risk for reoperation when compared with patients with a normal femoral fracture. However, this risk is less likely to be dependent on the type of fracture than other factors such as age, gender, comorbidities and survival. Using an implant that protects the fragile proximal femur, the risk for reoperations can be attenuated dramatically. An intramedullary nail with fixation of the femoral neck protects the femur from subsequent hip fractures – the most common complication in elderly patients with any type of femoral shaft fracture.

Atypical femoral fractures are difficult to identify in the population. Erroneous diagnosis coding, poor reporting of adverse drug reactions and low accuracy of radiology reports make the identification and surveillance a difficult task. The Swedish Fracture Register has provided the option to register this special fracture since 2015. With its physician-based registration process, it enables researchers and treating physicians to identify and follow these rare fractures longitudinally.

Atypical femoral fractures are burdened with a high rate of reoperation. In our nationwide analysis, the increased rate of reoperation was related to patient background characteristics, such as age and health status, rather than fracture type. Introduction Patients with atypical fractures are complex to treat and burdened with a high risk of reoperation. We hypothesized that patients with surgically treated, complete atypical fractures have a higher risk of any reoperation and reoperation related to healing complications than patients with common femoral shaft fractures but that this increase would become insignificant when adjusted for predefined characteristics. Methods A cohort of 163 patients with atypical fractures and 862 patients with common femoral shaft or subtrochanteric fractures treated from 2008 to 2010 and who had follow-up radiographs and register data available until 31 December 2014 was included. Reoperations were identified by a complementary review of radiographs and register data and were used to calculate risks for any reoperation and reoperations related to healing complications. Results Patients with atypical fractures were more likely to be reoperated for any reason, age-adjusted OR 1.76 (95% CI, 1.08 to 2.86). However, patients with common fractures had a shorter follow-up due to a threefold higher death rate. Accordingly, in a multivariable-adjusted time-to-event model, the increased risk lost statistical significance for any reoperations, cause-specific HR 1.34 (95% CI, 0.85 to 2.13), and for reoperations related to healing complications, HR 1.32 (95% CI, 0.58 to 3.0). Continued use of bisphosphonate in the first year after the fracture did not affect the reoperation rate. Conclusions Our findings suggest that the increased risk of reoperation after an atypical femur fracture is largely explained by patient characteristics and not fracture type.

Background and purpose - To continuously assess the incidence of atypical femoral fractures (AFFs) in the population is important, to allow the evaluation of the risks and benefits associated with osteoporosis treatment. Therefore, we investigated the possibility to use the Swedish Fracture Register (SFR) as a surveillance tool for AFFs in the population and to explore means of improvement. Patients and methods - All AFF registrations in the SFR from January 1, 2015 to December 31, 2018 were enrolled in the study. For these patients, radiographs were obtained and combined with radiographs from 176 patients with normal femoral fractures, to form the study cohort. All images were reviewed and classified into AFFs or normal femur fractures by 2 experts in the field (gold-standard classification) and 1 orthopedic resident educated on the specific radiographic features of AFF (educated-user classification). Furthermore, we estimated the incidence rate of AFFs in the population captured by the register through comparison with a previous cohort and calculated the positive predictive value (PPV) and, where possible, the inter-observer agreement (Cohen's kappa) between the different classifications. Results - Of the 178 available patients with AFF in the SFR, 104 patients were classified as AFF using the goldstandard classification, and 89 using the educated-user classification. The PPV increased from 0.58 in the SFR classification to 0.93 in the educated-user classification. The interobserver agreement between the gold-standard classification and the educated-user classification was 0.81. Interpretation - With a positive predictive value of 0.58 the Swedish Fracture Register outperforms radiology reports and reports to the Swedish Medical Products Agency on adverse drug reactions as a diagnostic tool to identify atypical femoral fractures.

Background: In Sweden, approximately 1 in 4 women who are &gt;= 50 years of age will sustain a hip fracture. Patients treated for a femoral shaft fracture are likely to have an even higher risk. We hypothesized that intramedullary nails protecting the femoral neck reduce the risk of subsequent hip fracture and allow the patient to avoid a challenging reoperation. Methods: Between 2008 and 2010, 5,475 fractures of the femoral shaft, in patients who were &gt;= 55 years of age, were registered in a national registry in Sweden. Of these patients, 897 fulfilled the inclusion criteria. We used radiographs and register data to identify the reasons for and the types of reoperation that occurred between the index surgical procedure and December 31, 2014. The categories of implants were determined through a review of radiographs as intramedullary nails with and without femoral neck protection. Reoperations related to peri-implant fractures (including hip fractures) were analyzed as a subgroup of all major reoperations. Multivariable-adjusted, cause-specific hazard ratios (HRs) were calculated to compare the risk of reoperation between cases with nails with and without femoral neck protection. Results: Among the 897 patients, a total of 82 reoperations were performed. In 640 patients who were treated with intramedullary nails with femoral neck protection, there were 7 peri-implant fractures (no hip fractures) and 27 major reoperations. Among the 257 patients who were treated with intramedullary nails without femoral neck protection, 14 peri-implant hip fractures and 24 major reoperations were identified. Patients who received nails with femoral neck protection had a lower hazard for any peri-implant fracture (multivariable-adjusted cause-specific HR, 0.19 [95% confidence interval (CI), 0.07 to 0.5]) and major reoperation (multivariable-adjusted cause-specific HR, 0.51 [95% CI, 0.28 to 0.92]). Conclusions: Intramedullary nails with femoral neck protection in the treatment of low-energy femoral shaft fractures prevent secondary hip fractures and decrease the overall risk of reoperation for 4 to 6 years postoperatively.

Objective: Immediate cartilage structural alterations in the acute phase after an anterior cruciate ligament (ACL) rupture may be a precursor to posttraumatic osteoarthritis (PTOA) development. Our aim was to describe changes in cartilage matrix in the subacute phase of the acutely ACL-injured knee compared to the contralateral uninjured knee. Design: Participants (n = 118) aged 15-40 years with an acute ACL injury were consecutively included in subacute phase after acute ACL-injury and underwent MRI (mean 29 days post trauma) of both knees. Mean T2 relaxation times, T2 spatial coefficient of variation and cartilage thickness were determined for different regions of the tibiofemoral cartilage. Differences between the acutely ACL-injured and uninjured knee were evaluated using Wilcoxon signed-rank test. Results: T2 relaxation time in injured knees was increased in multiple cartilage regions from both medial and lateral compartment compared to contralateral knees, mostly in medial trochlea and posterior tibia (P-value&lt;0.001). In the same sites of injured knees, we observed significantly thinner cartilage. Moreover, injured knees presented shorter T2 relaxation time in superficial cartilage on lateral central femur and trochlea (P-value&lt;0.001), and decreased T2 spatial coefficient of variation in lateral trochlea and load bearing regions of medial-central femoral condyle and central tibia in both compartments. Conclusion: Small but statistically significant differences were observed in the subacute phase between ACL-injured and uninjured knee in cartilage T2 relaxation time and cartilage thickness. Future longitudinal observations of the same cohort will allow for better understanding of early development of PTOA. (C) 2022 The Author(s). Published by Elsevier Ltd on behalf of Osteoarthritis Research Society International.