Background: During 1978 and 1979, we initiated a prospective multicenter study to evaluate the results of nonoperative treatment of primary anterior shoulder dislocation. In the current report, we present the outcome after twenty-five years. Methods: Two hundred and fifty-five patients (257 shoulders) with an age of twelve to forty years who had a primary anterior shoulder dislocation were managed with immobilization (achieved by tying the arm to the torso with use of a bandage) or without immobilization. All 227 living patients (229 shoulders) completed the follow-up questionnaire, and 214 patients completed the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. Results: Ninety-nine (43%) of 229 shoulders had not redislocated, and seventeen (7%) redislocated once. Thirty-three recurrent dislocations had become stable overtime (14.4%), and eighteen were considered to be still recurrent (7.9%). Sixty-two shoulders (27%) had undergone surgery for the treatment of recurrent instability. Immobilization after the primary dislocation did not change the prognosis. Only two of twenty-four shoulders with a fracture of the greater tuberosity at the time of the primary dislocation redislocated (p < 0.001). When shoulders with a fracture of the greater tuberosity were excluded, forty-four (38%) of 115 shoulders in patients who had been twelve to twenty-five years of age at the time of the original dislocation and sixteen (18%) of ninety shoulders in patients who had been twenty-six to forty years of age had undergone surgical stabilization. At twenty-five years, fourteen (23%) of sixty-two shoulders that had undergone surgical stabilization were in patients who subsequently had a contralateral dislocation, compared with seven (7%) of ninety-nine shoulders in patients in whom the index dislocation had been classified as solitary (p = 0.01). Gender and athletic activity did not appear to affect the redislocation rate, however, women had worse DASH scores than men did (p = 0.006). Conclusions: After twenty-five years, half of the primary anterior shoulder dislocations that had been treated nonoperatively in patients with an age of twelve to twenty-five years had not recurred or had become stable over time. Level of Evidence: Prognostic Level I. See Instructions to Authors for a complete description of levels of evidence. Copyright © 2008 by the Journal of Bone and Joint Surgery, Incorporated.

The interest for surgery simulator systems with anatomical models generated from authentic patient data is growing as these systems evolve.With access to volumetric patient data, e.g., from a computer tomography scan, haptic and visual feedback can be created directly from this dataset. This opens the door for patient specific simulations. Hip fracture surgery is one area where simulator systems is useful to train new surgeons and plan operations. To simulate the drilling procedure in this type of surgery, a repositioning of the fractured bone into correct position is first needed. This requires a segmentation process in which the bone segments are identified and the position of the dislocated part is determined. The segmentation must be automatic to cope with the large amount of data from the computer tomography scan. This work presents the first steps in the development of a hip fracture surgery simulation with patient specific models. Visual and haptic feedback is generated from the computer tomography data by simulating fluoroscopic images and the drilling process. We also present an automatic segmentation method to identify the fractured bone and determine the dislocation. This segmentation method is based on nonrigid registration with the Morphon method.

The authors have evaluated a trauma simulator based on virtual reality techniques. Ten surgeons and 15 medical students performed distal locking of a femoral nail (A). Furthermore, 10 medical students performed simulated osteosynthesis of a femoral neck fracture (B). Total surgery time (A) (mean value) was shorter for surgeons (108 s) compared with students (157 s) at the first (p = 0.033), second (102 respectively 138 s, p = 0.13) and third (96 respectively 160 s, p = 0.15) operation. Total fluoroscopy time (A) (mean value) was shorter for surgeons compared with students at the first (45 respectively 89s p = 0.001), second (48 respectively 83 s, p = 0.02) and third (50 respectively 107 s, p = 0.10) operation. The positioning of the hip nails (B) improved between the first and last trial. Total surgery and fluoroscopy time were reduced. All participants thought that this and similar simulators should be part of the programme and that this simulator would be helpful if they were about to learn the procedures).

This study was designed to investigate human surgical specimens from patients with impingement (n = 16), ruptured supraspinatus tendons (n = 7), frozen shoulder (n = 2) and controls (n = 9) with respect to histological changes and the presence of fibronectin and Matrix metalloprotease-1 (MMP-1). The biopsy of the middle part of the supraspinatus tendons was analyzed microscopically after staining with hematoxyline eosin, Van Giesons hematoxyline and Phospho Tungstic Acid Hematoxyline for visualization of fibrin. Immunofluorescent stainings for fibronectin and MMP-1 were performed. Histology and immunofluorescence were assessed blindly. Necrotic tendinous tissue and fibrin were found only in some specimens from ruptures. The staining for fibronectin was significantly increased among patients with a rupture. MMP-1 was, however, only infrequently found in specimens from patients with impingement and ruptures. Fibrosis and thinning of fascicles seemed to be a more non-specific finding, appearing in control, impingement and rupture specimens. In conclusion, necrotic tendinous tissue, fibrin and fibronectin appear to be signs of tendon degeneration, whereas fibrosis and thinning of fascicles were found also in controls. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.

Purpose: The purpose of this study was 2-fold: to document the accuracy of a new measuring device and to intraoperatively compare the subacromial distance between controls and patients with impingement syndrome before and after arthroscopic subacromial decompression (ASD).

Type of Study: Clinical study.

Methods: When performing an ASD, it is important that bone resection is adequate. Today the correct subacromial distance after bone resection is only assessed by eye, directly or indirectly. The subacromial distance was measured between the anterolateral corner of the acromion and the supraspinatus tendon in the lateral decubitus position. The device was inserted 2 to 3 cm below the anterolateral acromion. There was no subacromial pathology among the controls (n = 15, mean age, 28 years). In 30 patients with impingement syndrome (average age, 53 years) an ASD was performed. The subacromial distance was measured after bursectomy and then after bone resection. Intraindividual and interindividual assessment was performed.

Results: The mean value of the subacromial distance in controls was 16 mm, the 95% confidence limits between 14 and 18 mm. The mean value in the group of patients with impingement syndrome was 8 mm before and 16 mm after the decompression. Due to the pressure within the subacromial space, the subacromial distance increased 1 mm. Intraindividual measurements never varied more than 1 mm (n = 5). The correlation coefficient between the measurements by both authors was 0.99.

Conclusions: In this study, we assessed and described the use of a measuring device that enables the surgeon to quantify the subacromial distance before and after bone resection. After bone resection, the mean value of the subacromial distance was well within the control values. The amount of bone resected varied from 5 to 13 mm. This new device enables documentation in clinical work as well as in research.

This study was designed to investigate the histologic expression of the rat's supra- and infraspinatus tendons in carrageenan-induced subacromial bursitis. Thirty-two rats received subacromial injections with carrageenan (n = 28) or saline (n = 4). The tendons were analysed microscopically after staining with hematoxyline eosin, Van Giesons hematoxyline and immunofluorescent staining of fibronectin and fibrinogen. In the controls (saline × 10) and group A (carrageenan × 5) there were no changes in the tendons. In group B (carrageenan × 10) 3/8 rats showed macrophages between the collagen fibres and an increased staining of fibronectin. In group C (double dosis carrageenan) all rats had signs of fibrocartilaginous metaplasia in the supraspinatus tendon. In eight of these specimens even bony metaplasia was seen. The infraspinatus tendon showed fibrosis but no fibro-cartilaginous metaplasia. The results showed that iatrogenic bursitis after carrageenan subacromial injections was associated with marked changes of the supraspinatus tendon.

Assessing laxity of the shoulder joint in patients who are under anesthesia is a standard procedure before arthroscopy. The aim of this study was to evaluate a novel instrument for quick and reliable intraoperative measurement of glenohumeral translation. Previous testing of various designs has resulted in a device secured by 1 pin in the acromion and 1 pin in the proximal humerus. These pins are interconnected by a sliding ruler that gives translation values in millimeter increments as the laxity tests are performed. Comparison between manual arbitrary approximation of laxity and instrumented translation measurements showed that manual testing is reasonably good for assessment of anterior and posterior translation, without, however, providing values of translation in millimeter increments. The low correlation between manual assessment and instrumented inferior translation measurements indicates that inferior translation is more difficult to approximate manually. The shoulder translation tester was used in 102 patients. The mean values for clinically stable shoulders (n = 58) were 5 mm for anterior translation, 5 mm for posterior translation, and 4 mm for inferior translation. The corresponding values in unstable shoulders were significantly higher than in the stable shoulders, especially in patients with multidirectional instability. We conclude that the shoulder translation tester is easy and quick to use. It provides quantitative values of translation and will thus contribute information for correct diagnosis, therapy, and documentation.

The supraspinatus tendon is an important structure of the rotator cuff. Subacromial impingement is a common reason for shoulder pain. Despite extensive scientific work in this field, the cause of impingement syndrome is still not fully understood. The general aim of the present thesis was to generate new knowledge with respect to pathogenesis and treatment of impingement syndrome. A combination of animal and clinical studies were performed. Different methods were used such as histology, immunohistochemistry, development and assessment of a novel measuring device and clinical and radiological assessment.

Thirty rats were injected with triamcinolone or saline into the subacromial bursa. After five corticosteroid injections, we found focal inflammation, degradation and fragmentation of collagen bundles in the supraspinatus tendon, whereas the control specimens were normal (p=0.035).

Subacromial bursitis was induced by injections of carrageenan into the subacromial space (n=28). Fibrocartilaginous metaplasia and bony metaplasia were found in the supraspinatus tendon. Even in specimens with no histologic changes of the collagen bundles the staining for fibronectin was significantly increased.

The distance between the anterolateral acromion and the supraspinatus tendon was measured in patients with impingement syndrome intraoperatively (n=30) and in controls (instability, n=15). The mean value of the subacromial distance in controls was 16 mm, the 95% mean confidence limits between 14 and 18 mm. The mean value in the group of patients with impingement syndrome was 8 mm before and 16 mm after the decompression.

Fifty patients were reviewed after arthroscopic subacromial decompression. Twenty-five showed calcific deposits in the rotator cuff on radiographs preoperatively. In 13 patients the calcific deposits totally disappeared postoperatively. In another six patients the calcifications had decreased in size. Four patients still showed calcifications, which were 5 mm or greater in size. The postoperative results measured by the Constant score were almost identical in the calcific and the non-calcific groups. Tillander 010916 8 Human surgical supraspinatus tendon specimens were studied from patients with impingement (n=16), ruptured supraspinatus tendons (n=7) and controls (n=10). Degradation of tendinous tissue and fibrin were found only in some specimens from ruptures. The difference in fibronectin staining was significant between controls and patients with a rupture (p=0.002). Fibrosis and thinning of fascicles seemed to be a more non-specific finding, appearing in control, impingement and rupture specimens.

In conclusion, subacromial corticosteroid injections may cause rupture of the supraspinatus tendon. Metaplasia of the supraspinatus tendon may play a role in the pathogenesis of impingement and rupture of the supraspinatus tendon. The subacromial distance can be measured intraoperatively and was shown to be lower in patients with impingement than in patients with instability. Calcifications disappear or decrease in size after arthroscopic subacromial decompression and do not seem to influence the postoperative outcome in patients with impingement. Degradation of tendon tissue, fibrin and fibronectin appear to be signs of tendon degeneration, whereas fibrosis and thinning of fascicles were found also in controls.

33 rheumatoid patients, treated with hemispherical cup resurfacing hemiarthroplasty of the shoulder without medullary fixation (6 bilaterally), were reviewed after mean 4.4 (2-6) years. The median Constant score was 30 (15-79), mean proximal migration of the humerus 5.5 (SD 5.2) mm and mean glenoid erosion 2.6 (SD 1.7) mm. Proximal migration and glenoid erosion did not correlate with shoulder function or pain. Radiographic signs of loosening (changes in cup inclination combined with changes in cup distance above the greater tuberosity) occurred in one quarter of the shoulders. At follow-up, 26 patients were satisfied with the procedure, despite poor shoulder function and radiographic deterioration.

The aim of this study was to evaluate the effects of repeated steroid injections into the subacromial space. Thirty rats were injected either 3 or 5 times with triamcinolone in a dosage equivalent to that given to human beings or 3 or 5 times with saline into the subacromial space. One rat received no injection. The supraspinatus and infraspinatus tendons were evaluated macroscopically and microscopically. Two different staining methods were used on each sample including hematoxylin eosin and Miller's elastin/van Gieson's solution. After 5 steroid injections, we found focal inflammation, necrosis, and fragmentation of collagen bundles in the tendon in 4 of 7 rats. The tendons of the controls showed a normal structure (P < .05). There were no pathologic changes among the rats that were injected with triamcinolone 3 times. These results show that repeated subacromial injections of triamcinolone may cause damage to the rotator cuff of the rat. This finding may indicate cautious use of subacromial steroid injections in human beings.