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Aim: The subscapularis muscle is an important active stabilizer of the glenohumeral joint. For this radiological study, we investigated if its radiological integrity is affected after arthroscopic glenoid reconstruction. In the technique used, an autologous iliac crest graft is transported through the rotator interval, and the graft is fixed via an antero-inferior portal with compression screws., Methods: 3 women and 6 men (mean age 31 ± 9 years, min 21, max 46 years) who had a preoperative glenoid deficit of 23% ± 6% (min 13%, max 29%) were included. In a follow-up after an interval of 34 months (min 19, max 50), MRI scans were performed on both shoulders. With ITK-SNAP, a 3D reconstruction software, the volume of the subscapularis muscle in the injured and contralateral shoulder was measured. In addition, signal intensity ratios (PSI) (infraspinatus muscle / cranial subscapularis muscle and infraspinatus muscle / caudal subscapularis muscle) were analyzed and the width of the cranial and caudal portions as well as the length of the subscapularis muscle in the parasagittal plane were determined., Results: The 3D volume showed no difference between operated and healthy shoulders (p = 0.07), neither did PSI ratios (infraspinatus muscle / cranial subscapularis muscle: p = 1.00, infraspinatus muscle / caudal subscapularis muscle: p = 1.00). In the parasagittal plane, length (p = 0.09) and cranial width (p = 0.23) did not differ. However, the width of the lower muscle was increased in injured shoulders (p = 0.02)., Conclusion: In this cohort, no relevant volume loss could be found after arthroscopic glenoid reconstruction. However, a greater width of the lower muscle portion could be identified in the parasagittal plane as a possible indication of scarring.

Introduction: The purpose of this proof-of-concept study was to investigate the biomechanical performance of two surgical techniques, namely (1) the double Tight-Rope fixation with an additional acromioclavicular FiberTape fixation (DTRC) and (2) the fixation of the clavicle to the acromion and coracoid in a bipodal manner (Bipod) using a Poly-Tape and FiberTape. Both techniques intend to address vertical and horizontal instability after acromioclavicular dislocation. They were compared with the commonly used (3) double Tight-Rope (DTR) technique, which only stabilizes the clavicle to the coracoid., Materials and Methods: The acromioclavicular joint (ACJ) of 18 composite Sawbone shoulder specimens (6 per reconstruction group) were tested for posterosuperior elongation (70N cyclical load, 1500 cycles), load-to-failure and stiffness., Results: After 1500 cycles, the DTRC, Bipod and DTR group showed an elongation of 0.45 mm (SD 0.14 mm), 1.19 mm (SD 0.54 mm), and 0.46 mm (SD 0.15 mm), respectively. Although the elongation of the Bipod group was increased when compared to the other two groups (Bipod versus DTRC p = 0.008; Bipod versus DTR p = 0.006), the difference was less than 0.7 mm. The DTRC showed a higher load-to-failure of 656.1N (SD 58.1 N) compared to the Bipod [531.1 N (SD 108.2N) (p = 0.039)] and DTR group [522.8 N (SD 32.8 N) (p = 0.033)]., Conclusion: The DTRC and the DTR group resulted in similar low elongation, while the elongation in the Bipod technique was slightly higher. Even though this difference of 0.7 mm shows statistical significance, it most likely has no clinical relevance. When testing in posterosuperior direction, which is the clinically relevant load vector, an additional fixation of the clavicle to the acromion did not reduce elongation in this study. It is, furthermore, questionable if the benefit of an increased load-to-failure in combination with no improvement in elongation and stiffness as seen in the DTRC group outweighs the possible risks and increased costs coming with the DTRC refixation.

Purpose: Arthroscopic Bankart repair (ABR) provides satisfactory results for recurrent anterior shoulder instability, but the high recurrence rate post-ABR remain a concern. One of the adjunct procedures proposed to improve ABR results is arthroscopic rotator interval closure (ARIC). This study prospectively evaluated the outcomes of ABRs alone compared to combined ABR + ARIC and identified risk factors related to failure of each procedure., Methods: Thirty-nine consecutive patients (mean age 23.1 (18.3-37.5) years; 37 males) underwent arthroscopic stabilization for recurrent anterior traumatic shoulder instability. Twenty patients underwent ABR alone and 19 underwent ABR + ARIC. Remplissage was added when glenoid engagement was observed during surgery. All patients were prospectively followed, and their postoperative courses were reviewed and functionally assessed at the last visit., Results: The re-dislocation rate was higher in the ABR + ARIC group compared to the ABR only group at a mean follow-up of 4.2 (2-5.6) years (3 vs. 0, P = 0.06). More subluxations were found in the ABR only group (2 vs. 1, respectively; P = 0.58). The final limitation of range of motion (ROM) compared with the preoperative ROM was similar in both groups. Remplissage procedures were performed more often in the ABR only group [12 (60%) vs. 4 (21%), P = 0.013]., Conclusions: ARIC performed as an adjunct to ABR showed no superiority in attaining value-added stability compared to ABR alone. Adding a remplissage procedure may achieve better stability., Level of Evidence: Level 2.

Purpose: Anterior shoulder dislocation can be associated with many lesions such as Bankart lesions, rotator cuff tears (RCT), Hill-Sachs lesions or greater tuberosity fractures. It has been documented that early management of the associated injury affords better recovery of shoulder function. The aim of this study was to highlight the incidence of associated injuries after anterior shoulder dislocation., Methods: A total of 240 patients with traumatic anterior glenohumeral dislocations were subjected to complete history taking, neurovascular assessment and pre-reduction plain X-ray. An X-ray was taken immediately after reduction. Ultrasonography (US) and magnetic resonance imaging (MRI) were done within one week after reduction in all patients. Nerve conduction studies were ordered for any patient with suspected nerve injury., Results: Associated lesions were reported in 144 (60%) patients. RCT was the most common injury (67 cases). It was isolated in 34 patients (14.15%), while it was combined with other lesions in 33 cases (13.75%). Axillary nerve injury was encountered in 38 patients, of them 8 (3.33%) were isolated and 30 (12.5%) were combined. Greater tuberosity fracture was found in 37 patients, of them 15 (6.25%) were combined with axillary nerve injury, and in the other 22 patients (9.17%) the fracture was isolated. All cases with Hill-Sachs and Bankart lesion were combined lesions with no isolated cases. There was a significant relation between the incidence of associated injuries and age, mechanism of injury and the affected side., Conclusions: Lesions associated with traumatic anterior glenohumeral dislocations are more frequent than expected. Thorough clinical examination and detailed imaging including US and MRI are mandatory to avoid a missed diagnosis.

Background and Introduction: The incapacity with respect to work following anterior-inferior shoulder dislocation and subsequent Bankart repair has not been previously examined. The objective of this study was to examine a patient's incapacity according to the classification by the REFA Association. The recovery time was measured and the outcome of patients with heavy workload was compared to those with lower workloads., Materials and Methods: A total of 74 patients who underwent isolated arthroscopic Bankart repair fulfilled the inclusion criteria. The Constant-Murley Score, UCLA Shoulder Score and ROWE Score for Shoulder Instability were recorded for clinical assessment. The mean follow-up time was 43.1 months (SD ± 17.4; 24-110 months) with a mean age of 34.7 years (SD ± 12.6). Workload was classified as per the REFA Association classification system. Postoperative duration of a patient's incapacity with respect to work and other subjective ratings were provided by the patients themselves., Results: The mean incapacity of work was 2.73 months (95 % CI 1.19-5.36). The incapacity of work was 2.06 months (95 % CI 1.55-2.68) in the group with low physical strains at work (REFA 0-1) and 3.40 months (95 % CI 2.70-4.24) in the group with heavy workload (REFA 2-4/p = 0.005). Overall, the mean Constant-Murley Score was 87.7 (SD ± 13.5). The average UCLA Shoulder Score summed up to 31.9 (SD ± 3.87) and the mean ROWE Score was 87.6 (SD ± 21.7). 13 (17.5 %) patients had problems to compete in their jobs. Three patients had to change the job postoperatively., Conclusion: In this study, a relationship between the time of incapacity of work and the workload was observed; patients with low physical strains returned significantly earlier to work after arthroscopic Bankart repair (p = 0.005). In general, the clinical results as measured in the Constant/UCLA/Rowe score were comparable to other studies.

Chronic bilateral anterior shoulder dislocation is a rare entity. Treatment options range from conservative to surgical reduction. We present a case of a young bench-pressing athlete with bilateral locked anterior shoulder dislocation without fracture. Upon presentation, the patient had no pain with functional range of motion so he refused surgery. Conservative treatment could be an acceptable alternative to surgical intervention if pain and functional status are satisfactory.

Purpose: To evaluate the effectiveness and safety of arthroscopic and open Bankart repair for recurrent anterior shoulder dislocation using meta-analysis of data from clinical trials., Materials and Methods: Cochrane Register of Controlled Trials, PUBMED and EMBASE were used to search and identify clinical trials that evaluated arthroscopic and open Bankart repair for recurrent anterior shoulder dislocation. Methodological qualities of studies were assessed by Cochrane Collaboration tool for assessing risk of bias and Newcastle-Ottawa Scale. Publication bias was detected using Begg's test and Egger's test., Results: Sixteen trials involving 827 shoulders were included in the study. Based on Cochrane Collaboration tool for assessing risk of bias, three studies were rated as high quality and one study was rated as moderate quality among the randomized controlled trials. Another twelve case-control studies were rated as high quality based on Newcastle-Ottawa Scale. No significant publication bias was detected by Begg's test or Egger's test. Meta-analysis results indicated that arthroscopic repair has a significantly better recovery rate for external rotation at 90° of abduction, external rotation at side (P > 0.05) and forward flexion. However, arthroscopic repair had higher rates of recurrence and reoperation than open Bankart repair., Conclusion: Meta-analysis of available randomized controlled trials and case-control studies demonstrated that arthroscopic repair and open Bankart repair were similar in safety. Arthroscopic repair resulted in better recovery of range of motion, but recurrence and reoperation rates were higher than open Bankart repair.

Background: Posterior dislocation of the shoulder is a rare injury and often misdiagnosed during the initial presentation to a physician. Misdiagnosis is due to a lack of clear clinical signs compared to anterior dislocation and inappropriate radiographs. In contrast to anterior dislocations, the humeral head defect accounts for recurrent instability. Depending on the size of the defect and the duration of dislocation, different treatment options include elevation of the defect, bone grafting, McLaughlin procedure, rotation osteotomy or arthroplasty., Methods: We reviewed 35 patients who presented to our institution with a locked posterior dislocation of the shoulder between January 1999 and August 2009. In 6 patients, the shoulder remained stable after closed reduction, so the treatment was conservative; 29 patients underwent surgery., Results: The mean follow-up was 55 months (range 11-132 months). The interval between trauma and the diagnosis of posterior shoulder dislocation was 66 days (min. 0, max. 365). Patients treated conservatively achieved a Constant Score of 85 points; patients who underwent operative treatment had a slightly worse outcome with an average Constant Score of 79 points. There was a high correlation between the time to the correct diagnosis and the outcome., Conclusion: Although locked posterior shoulder dislocation is uncommon and often initially misdiagnosed, satisfying results can be achieved by different surgical treatment options. Early diagnosis by detailed clinical examination and sufficient radiographic evaluation with true anterior-posterior and axillary views is essential to improve clinical results. Levl of evidence: IV.

Purpose: The purpose of this study was to compare clinical outcomes between a primary dislocation group (group P) and a recurrent dislocation group (group R) with combined lesion of Bankart and type II SLAP lesions (type V SLAP lesion) and to evaluate incidence of type V SLAP lesion. In addition, the authors evaluated clinical outcomes of these patients by dividing two groups according to the sequence for Bankart and SLAP lesion suture., Methods: From May 2000 to May 2005, 310 patients who gave informed consent, underwent the diagnostic arthroscopy and magnetic resonance arthrography (MRA). One hundred and ten patients met the following criteria: (1) post-traumatic primary or recurrent anterior shoulder instability, (2) a normal contralateral shoulder, (3) a type V SLAP lesion, and (4) minimum follow-up of two years. Group P included 42 patients, and group R, 68 patients. Among all patients, 58 patients who had Bankart lesions sutured first were included in group B, and 52 who had their SLAP lesions sutured beforehand, group S. Visual analogue scale, range of motion, Rowe and Constant score were used to compare results between group P and group R, also group B and group S., Results: The incidence rates of type V SLAP lesion were 42.8% in group P and 32.0% in group R. The overall treatment results in our study were good. Even if the difference between the two groups was statistically insignificant, group P showed greater recovery of range of motion than group R in external rotation. No significant difference was found between the two different operative methods according to suture sequence., Conclusion: The incidence rates of type V SLAP lesion were 42.8% in the primary dislocation group and 32.0% in the recurrent dislocation group. The overall treatment results in our study were good. Although there was no statistical significance in surgical time between the two groups, when both SLAP and Bankart lesions are present, the Bankart lesion must be sutured first to reduce surgical time.

Objective: The purpose of this study was primarily to assess the diagnostic performance of magnetic resonance imaging (MRI) in detecting articular cartilage injuries in patients with glenohumeral instability. A secondary purpose was to assess the diagnostic performance of MRI for detection of Hill-Sachs and Bankart lesions., Materials and Methods: A cohort of 87 consecutive patients who underwent diagnostic MRI and shoulder arthroscopy for instability from 1997 to 2006 were identified. Fifty-five patients (63.2%) underwent MRI with intra-articular contrast medium and 32 patients (36.8%) underwent MRI without contrast medium. MR images were reviewed by two radiologists and interpreted by consensus for the presence of articular cartilage lesions (including Hill-Sachs and Bankart lesions), which were then confirmed by reviewing the operative report and images recorded at arthroscopy., Results: Mean patient age was 27.0 ± 10.2 years with a mean clinical and radiographic follow-up of 29 (range 3-72) months. Cartilage injuries were detected arthroscopically in 55 patients (63%). Bankart and Hill-Sachs lesions were identified arthroscopically in 66 patients (75.9%) and 55 patients (63.2%) respectively. The overall sensitivity and specificity for detection of glenohumeral articular cartilage lesions by MRI were 87.2% and 80.6% respectively. The sensitivity and specificity of MRI in detecting Bankart lesions was 98.4% (95% CI 91.9, 99.7) and 95.2% (95% CI 77.3, 99.2) respectively. The sensitivity and specificity of MRI in detecting Hill-Sachs lesions was 96.3% (95% CI 87.6, 98.9%) and 90.6% (95% CI 75.7, 96.9) respectively. No statistically significant difference was found between MRI examinations with and without intra-articular gadolinium (p = 0.89)., Conclusion: Magnetic resonance imaging demonstrates high sensitivity and specificity for the diagnosis of articular cartilage injuries in patients with glenohumeral instability. MRI with or without intra-articular contrast medium in this study were equally reliable as a non-invasive method for assessment of articular cartilage damage of the glenohumeral joint prior to diagnostic arthroscopy.

Follow-up examinations of 45 patients who received shoulder arthroplasty for osteoarthritis following shoulder instability were conducted after 44 months. The goal of this study was to describe the clinical findings associated with advanced glenohumeral arthritis due to shoulder instability and instability repairs and to present the clinical results and complications of treating this with shoulder arthroplasty. The weighted average Constant score increased significantly from 49.4 to 81.3 points. There was no significant difference in the type of arthroplasty with 35 cases of total shoulder replacements and ten cases of hemiarthoplasty. The rate of complications was 40% (18/45 patients) with 20% (9/45 patients) requiring an operative revision. Patients with arthritis after instability repair showed great improvement in all qualities of the Constant score. Nonetheless, further analyses are required to determine why such a relatively young group of patients showed high complication rates.

Posterior dislocations of the glenohumeral joint are extremely rare (2-4% of all shoulder dislocations) and often associated with bone or ligamentary injuries. Though the reverse Hill-Sachs lesion is a common injury associated with posterior shoulder dislocation, there have been only few articles describing specific treatments for this type of humeral head defect. This article describes the successful operative treatment of an acute locked posterior shoulder dislocation by reconstructing the articular surface of the humeral head with the use of autologous bone graft taken from the iliac crest. The patient was doing quite well with no complaints, good range of shoulder motion and no recurrence of posterior shoulder dislocation despite several epileptic seizures, 1.5 years after surgical reconstruction of the anatomy of the humeral head. His right shoulder function revealed to be "excellent" or "good", assessed with an absolute Constant Score of 76 points and a relative Score of 88% when compared with an age- and sex-matched normal population.

A case of bilateral anterior glenohumeral dislocation in a middle aged horse rider was presented. The patient was an amateur rider who sustained the injury when the horse reared suddenly. The rider fell back from the saddle while holding the halter. The shoulders were dislocated by a violent traction when shoulders were in internal rotation and flexion in sagittal plane and slight abduction in coronal plane. To the best of our knowledge this case is the third glenohumeral dislocation by forward traction. A review of the literature is presented.

The purpose of the study was to analyse the clinical results of an open Bankart repair for anterior instability in patients with a glenoid defect and those without a glenoid defect, and to identify factors related to the glenoid defect associated with anterior instability. The prospective study involved 20 patients with a glenoid defect (glenoid defect group) and 20 patients without a glenoid defect (control group) who were enrolled after an open Bankart repair. The average age of each group at the time of surgery was 28 and 23 years respectively. The average follow-up periods were 48 and 55 months. There were no significant differences in subjective pain and stability between the two groups. But the final Rowe score decreased significantly as the size of the glenoid defect increased. Redislocation or subluxation was seen in three patients in the glenoid defect group. The open Bankart procedure restored stability and improved shoulder functions in the patients with a glenoid defect associated with anterior instability, even though the glenoid defect group experienced a significant loss in the range of external rotation with the arm at the side, and the final outcome of the surgery depended upon the size of a glenoid defect. This was a therapeutic, level III case-control study.

Posterior shoulder instability occurs in approximately 2-5% of all cases of shoulder instability and treatment is still challenging. Open capsular plication procedures are described, but significant complications and risks have been reported in the literature. Arthroscopy has led to a better understanding of the pathoanatomy of posterior shoulder instability in recent years. We present our operative technique and the results of arthroscopic posterior shoulder stabilisation for the management of posterior shoulder instability. Sixteen patients with posterior shoulder instability were treated by arthroscopic posterior stabilisation from January 2004 to March 2005. There were 11 male and 5 female patients. The mean age was 24 (15-45) years. Nine patients had a unidirectional posterior instability. Seven patients had a predominantly posterior instability based on a multidirectional instability. Fourteen patients were evaluated after a mean follow-up of 12 (6-18) and 20 (14-26) months. Stability, range of motion and function were assessed using the Rowe score. The average Rowe score improved from pre-operative 32 (20-40) points to post-operative 87 (40-100) points after the first follow-up and 90 (40-100) points after the second follow-up. Furthermore subjective shoulder function was evaluated using a visual analog scale. The average score improved from pre-operative 3 (0-6) points to post-operative 8 (4-10) points after the first and second follow-up. At the first follow-up 93% of the patients had a stable shoulder; 85% had a stable shoulder after arthroscopic stabilisation at the second follow-up. Arthroscopic treatment for posterior shoulder instability is a demanding procedure. Due to a special operative technique with specific instruments soft tissue pathologies found in this type of instability such as capsular redundancy and labral tears can be addressed. Our results show that it can be used as an effective tool for the treatment of posterior shoulder instability.

In orthopaedic shoulder instability, muscle activity (EMG) is altered during unconstrained discrete arm movement tasks (e.g. elevation against a load). These findings have been ascribed to deficits in afferent feedback and neural control with glenohumeral instabilities resulting from orthopaedic injury. However, the integrity of neural control during shoulder movements in those with unstable shoulders is unclear. It is not known if there are altered EMG patterns during rhythmic arm movement or during discrete tasks involving no load, as would be experienced in many arm motions performed in daily living. The primary objective of this study was to evaluate neural control of arm movements between those with unstable shoulders and control participants, within a constrained arm movement paradigm involving both rhythmic arm cycling and discrete reaching. To achieve this objective, we determined if the amplitude and timing of EMG related to the movement pattern (background EMG) was significantly different between groups. Cutaneous reflexes were used to simulate a perturbation to the upper limb that would typically evoke a coordinated response. In the elevation phase of the movement path for anterior and posterior deltoid, upper trapezius, infraspinatus and serratus anterior, background EMG during rhythmic arm cycling was significantly (24%, p < 0.05) larger in unstable shoulders than in controls. No differences were found in background EMG between the groups during the discrete task. Significant differences (p < 0.05) were also noted in cutaneous reflexes between groups for both the rhythmic and discrete tasks with the reflex amplitudes being either increased or reduced in unstable shoulders as compared to controls. The differences in the background EMG and the cutaneous reflexes patterns in those with shoulder instabilities suggest that neural control is altered during rhythmic movement.

Objectives: The aim of the study was to quantify the decrease in glenohumeral stability following a global rotator cuff tear and to evaluate the effect of a decreased glenoid inclination angle through analysis of muscle force vectors in a computer model., Material and Methods: The lines of action of eight shoulder muscles were integrated into a standard geometric model. Muscle force magnitudes were estimated based on physiological cross-sectional area and normalized electromyographic activity. The magnitude and elevation angle of the resultant force vector was calculated at 0, 30, 60, and 90 degrees of abduction. A rotator cuff tear was simulated by reduction of the corresponding muscle force vectors., Results: At 0 and 30 degrees of glenohumeral abduction a global rotator cuff tear showed a resultant force vector pointing outside the glenoid. In the computer model, decreasing the inclination angle of the glenoid by 30 degrees increased the stability in rotator cuff-deficient shoulders., Conclusions: The results of this study provide a biomechanical rationale for clinical complications of global rotator cuff tear such as superior humeral head translation. The decreased glenoid inclination simulated in the computer model may represent a biomechanical basis for the development of new operative techniques to treat global rotator cuff tears.

Background: A questionnaire for patient self-assessment of shoulder function was designed. It was based on the internationally accepted Rowe score., Method: Explanations and photographs were added to the various parameters to make them easier to understand for the patients. A total of 95 patients completed the assessment form. The validity was tested by a correlation analysis comparing the questionnaire with the original score., Results: The questionnaire demonstrated a reproducible and significant (p<0.001), very high correlation (r>0.9) in the overall results and a moderate to very high correlation within single parameters (r>0.68)., Conclusion: Based on these results, it can be concluded that a valid and reproducible assessment of the original score is possible with the new questionnaire. Self-evaluation allows reliable assessment which is not dependent on the examiners or location, resulting in a higher number of patients reachable for follow-up studies.

We report an unusual case of bilateral anterior shoulder dislocation following trauma. Previously reported cases were either of bilateral dislocations or bilateral fracture dislocations. In our case the patient suffered bilateral anterior dislocation with a three part fracture dislocation on the right. A review of the literature is presented.

Thirty-four athletes (34 shoulders) with recurrent anterior glenohumeral instability were treated with a modified Bankart procedure, using a T-shaped capsular incision in the anterior capsule. The inferior flap was advanced medially and/or superiorly and rigidly fixed at the point of the Bankart lesion by a small cancellous screw and a spike-washer. The superior flap was advanced inferiority and sutured over the inferior flap. Twenty-five athletes (median age: 22) were evaluated over a mean period of follow-up of 65 months. The clinical results were graded, according to Rowe, as 22 (88%) excellent, 3 (12%) good, and none as fair or poor. The mean postoperative range of movement was 92 degrees of external rotation in 90 degrees of abduction. Elevation and internal rotation was symmetrical with the opposite side. Twenty-four patients returned to active sport, 22 at their previous level. This modified Bankart procedure is an effective treatment for athletes with recurrent anterior glenohumeral instability.

This retrospective study compares the long-term results of the treatment of 135 children with displaced extension-type supracondylar fractures of the humerus using 3 different methods. Closed reduction and percutaneous fixation was superior with excellent and good results in 87% and had the lowest incidence of poor results (8%). Open reduction and wire fixation, and closed reduction with a plaster cast gave excellent and good results in 74% and 60% respectively. Closed reduction and wire fixation is recommended as the treatment for grades II and III supracondylar fractures.

Objective: Post-traumatic recurrent dislocation is a major problem in the operative treatment of shoulder dysfunction in young athletes. This prospectively designed study evaluates the long-term results of a modified Eden-Hybinette procedure in young male athletes. The criteria were: capacity in sports, functional limit, and persistent pain. Genuine disorders of the glenoid or muscular imbalance of the shoulder joint were criteria for exclusion., Patients and Methods: From 1982 to 1990, 143 patients underwent surgery. Seventy percent were reevaluated within a minimum period of 18 months after the operation. The functional results were calculated using the ROWE score as well as a visual analog scale (VAS). X-rays were done after the patient had given informed consent., Results: VAS and ROWE score showed excellent/good results in 61%, fair results in 18%, and poor results in 21% of the documented cases. The rate of arthrosis was 25%. Redislocation occurred in 7%, mainly without any relevant trauma. The X-rays showed complete resorption of the bone graft in 30% of the cases. Best functional results and no redislocation were found in the patients who underwent surgery with fewer than 3 dislocations compared to those with more than 4 dislocation episodes., Conclusions: In cases of post-traumatic recurrent dislocation of the shoulder in young athletes, the modified Eden-Hybinette procedure is a good method of reestablishing sufficient stability of the shoulder. The operation should be performed prior to the 3rd dislocation episode. Four or more dislocation episodes show an increased tendency to redislocate and poor functional results.

After undergoing an operation according to the Eden-Lange technique, 56 patients with recurrent anterior shoulder luxation were re-examined clinically at an average follow-up period of 20 years. The mean age of the patients at the time of the operation was 24.9 years; the ratio of male to female patients was 2.3:1. The Ellman score (maximum of 27 points), stability tests, reluxation rate and X-ray examinations served as re-examination criteria. The mean score for the Ellmann test was 18.3 points; 29 patients had ventral instability. In the meantime 11 shoulders had redislocated. Fifty-one patients had arthrotic alterations in the operated shoulder. Because of the unsatisfactory functional and radiographical results, the Eden-Lange technique can no longer be accepted as the only treatment of choice for anterior shoulder dislocation.

The clinical features of a superior dislocation of the glenohumeral joint are described. Reposition, even under general anaesthesia, cannot be achieved. Associated supraspinatus tear, acromioclavicular separation and the dislocated position of the humeral head can be clearly visualized.

The influence of biomechanics in surgery of the locomotor apparatus has been constantly increasing over the last few decades. The purpose of this study was to determine wether biomechanical studies can significantly influence therapy and treatment of shoulder injuries, especially shoulder instability. The investigation was performed on 23 fresh human specimens with intact capsular ligaments of the glenohumeral joint. A Bankart lesion from 3 o'clock to 6 o'clock was repaired, and a Bankart repair and anterior inferior capsular shift, as described by Neer, were performed. The measurement was done on six clinically relevant positions of instability: superior, anterior, anterior-inferior, inferior, posterior-inferior, posterior. Measurement was done using a specially developed strain-gauge system. It was demonstrated that both instability and too much stability of the shoulder joint lead to a significant change in shoulder biomechanics. The anatomical O-position of the glenohumeral joint in 110 degrees of abduction is a position of about 60 degrees of external rotation compared to the O-position for clinical measurement. From the therapy point of view, one has to ask for anatomical reconstruction instead of tight repair in soft-tissue repair in the glenohumeral joint. Immediate post-operative rehabilitation in a 60 degrees range of motion is possible.

In an experimental study we investigated the EMG response in 10 patients after intraarticular stimulation of the joint capsule. Intraoperative stimulation was achieved by arthroscopic placement of the stimulation catheter at the anterior joint capsule. The muscle response was documented by mono- or bipolar electrodes. We found reproducible EMG muscle responses in both superficial and deep muscle layers. The response time was between 100 and 516 ms. The shortest muscle response was found at the anterior part of the deltoid muscle and the longest at the supraspinatus muscle and the lateral part of the deltoid muscle.

In a retrospective study we evaluated the long-term results of a modified Eden-Hybinette procedure in 76 patients. Besides stability, function, and subjective complaints, we documented in particular the degenerative changes of the joint. Subjective findings revealed excellent or good results in 68.5% of cases. In 20% of the patients the results were fair and in 11.5% poor. Some 66% of the patients had not subjective feeling of joint restriction. However, 25% complained of some and 9% of severe joint restriction. The overall recurrence rate was 13.9%. In patients with atraumatic dislocation the recurrence rate was 12%, in patient with voluntary dislocation it was 50%, and in posttraumatic instabilities the recurrence rate was 4.8%. The Rowe score showed 40% excellent and good results. The poor results were among the patients with redislocation, instabilities with subluxation, and secondary degenerative joint disease with concomitant pain and limitations in the range of motion. In patients with voluntary instabilities the poor results were in the group of redislocators, whereas in the posttraumatic group poor results were mainly due to degenerative joint disease. In 80% of the patients with bone block complications, secondary degenerative joint disease developed. Considering the relatively high recurrence rate and the amount of secondary degenerative joint disease after this procedure, we do not recommend this as a routine procedure for shoulder stabilisation.

The judgement of the correlation between an accident and a rotator cuff tear has an important role in legal and private accident insurance. Owing to the high morbidity of degenerative alterations and ruptures of the rotator cuff tendons, the causality of an acute traumatic rupture can be difficult to demonstrate, which means assessments are often controversial. In a retrospective study we evaluated 25 orthopaedic assessments and tried to find rules for an objective estimation. The judgement of correlation between trauma and rotator cuff tear should be based on four pillars: history, trauma mechanism, initial findings and course of the functional deficit. Possible mechanisms of traumatic rupture are discussed from various angles. Important clinical findings, e.g. a functional supraspinatus deficit, should be fully documented. X-Rays of both shoulders can lead to indirect demonstration of preexistent changes in the rotator cuff. Sonographic evaluation can show up the rotator cuff tear and demonstrate signs of acute injury. After persistent pain and functional deficit, in a few cases operative and microscopic findings will lead to a correct estimate of causality. Because of the diagnostic uncertainty a 20-point score is introduced for retrospective assessment of the history (2 points), trauma mechanism (3 points), initial clinical, radiological and sonographic findings (10 points) and course of functional deficit (5 points) to evaluate the role of trauma in rotator cuff tears. Using this score trauma can be classified as the main or partial cause or as irrelevant to the pathogenesis of rotator cuff tears.

A new method of reducing both anterior and posterior shoulder dislocations is described. Force is directed along the axis of the joint and minimal effort is required. The method is safe, simple and successful in both recent and delayed cases.

We have reviewed the history of 154 primary, traumatic dislocations of the shoulder in order to determine the risk of recurrence. We found a recurrence rate of 68% in patients under the age of 20, after a follow-up period of 1-9 years (average 4.5 years). There was a highly significant difference (p < 0.0001) in the recurrence rate of patients under, and above, 30 years of age. Twenty per cent of the patients had a concurrent minor fracture at the shoulder with 2 out of 39 of the recurrent cases (5%) and 29 of the 115 non-recurrent cases (25%); this is also a significant difference (p < 0.01). Neither the need for general anaesthesia at primary injury nor the occupation of the patient was a relevant factor in the final outcome of the dislocation. Four nerve injuries were encountered (3%), with no severe sequelae at follow-up. The young patient with no concurrent fracture at the time of the primary shoulder dislocation has a high risk of recurrence.

Commercially available fixation devices used for reattachment of capsuloligamentous tissue to the glenoid rim were tested until they failed in 42 human cadaveric shoulders, and compared to the tension strength of the standard Bankart procedure and that of the intact anterior capsule. The bone quality in the glenoid was measured by quantitative computed tomography, which allowed selective quantification of cortical and cancellous quantification of cortical and cancellous bone. The mean load at failure perpendicular to the bone surface varied from 90 to 115 N and was lower than in the standard Bankart procedure (127 N). All suture anchors demonstrated similar holding strength with the exception of an absorbable wedge (P < 0.05). Due to reduced mineral content in the inferior part of the glenoid, the fixation strength of all suture anchors was significantly decreased. In more than 20% a tension load of 100 N caused the suture anchor to pull out, but in general the fixation strength was limited by the suture attachment and the quality of the soft tissues. These data together with the first clinical results of 49 cases of anterior instability operated on between 1988 and 1992 allow the conclusion to be made that this modification will provide sufficient stability for early mobilization after surgical repair.

Passive glenohumeral joint stability was tested in ten cadaveric shoulder specimens, before and after venting of the intra-articular space. Force-displacement diagrams were measured with anterior, posterior and inferior excursion, in the neutral position, in 90 degrees of abduction and in a combination of 90 degrees of abduction and 90 degrees of external rotation. Displacement at 50 N prior to venting averaged 11.17 +/- 6.48 mm posteriorly, 7.15 +/- 5.51 mm anteriorly and 3.41 +/- 3.73 mm inferiorly. Venting of the joint increased displacement by 47% anteriorly, 49% posteriorly and 61% inferiorly. In addition, mathematical model calculation was used to estimate the destabilizing force present at the glenohumeral joint capsule during physiological arm motion. This force approximated 970 N, clearly more than passive stabilizers alone can provide. It is therefore assumed that in addition to passive glenohumeral joint stabilization, significant active forces are effective during arm motion.

A new method is presented for the reduction of shoulder dislocations and dislocation fractures, together with the follow-up results. This procedure is a modification of a method for reduction of the hip. Examination of our patients 1-3 years after the accident showed no sign of nerve lesions and little residual discomfort.

In human cadavers we were able to show that the glenohumeral joint is comparable to the model of a physical piston. The labrum glenoidale functions like a valve against atmospheric pressure. It is possible to characterize the behavior of intraarticular negative pressure by the equation (formula; see text). The calculations of the force F of atmospheric pressure tending to resist distraction of the joint surfaces leads to a 95% confidence interval from 6.9 to 22.9 kp. Under a general anesthetic, distraction of the healthy glenohumeral joint also produces negative intraarticular pressure in the area of the fossa glenoidalis in vivo. Joints with a labral tear (Bankart defect) and a chronic instability are not characterized by this phenomenon. A change in intraarticular pressure might stimulate intraarticular pressure receptors. This could be important in functioning as a neuromuscular protection reflex for the joint.

Subglenoid dislocation of the shoulder is uncommon. The clinical picture is striking and the radiographic appearances are characteristic, with the head of the humerus lying inferior to the glenoid and the shaft directed upwards and internally rotated. Complications such as associated fractures and injury to the brachial plexus or acillary vessels may occur. Fracture of the greater tuberosity or rupture of the rotator cuff is always seen. Post-traumatic frozen shoulder is common and leads to a poor functional result. The authors describe ten cases and review the literature. The mechanism of the injury is discussed and experimental evidence which supports the current concepts of shoulder instability is reviewed.

Nontraumatic glenohumeral subluxation can occur in patients with hemiplegia or brachial plexus involvement by tumor. Two cases of inferior subluxation of the humeral head are presented and nontraumatic etiologies of the "drooping shoulder" are discussed.