Outcome of pectoralis major transfer for the treatment of irreparable subscapularis tears

BACKGROUND: Chronic tears of the subscapularis tendon with or without associated tears of the supraspinatus and infraspinatus tendons may lead to pain and dysfunction of the shoulder. If conservative treatment fails and repair of the musculotendinous unit is impossible, transfer of the pectoralis major tendon can be attempted to substitute for lost subscapularis function. METHODS: Twenty-eight patients underwent a total of thirty consecutive pectoralis major transfers at an average age of fifty-three years. There were twelve isolated subscapularis tears and eighteen subscapularis tears associated with a tear of the supraspinatus or the supraspinatus and infraspinatus. All patients were examined clinically and with standard radiographs. RESULTS: The mean relative Constant score increased from 47% preoperatively to 70% at an average of thirty-two months postoperatively (p < 0.0001). The mean Constant scores for pain (p = 0.0009) and activities of daily living (p < 0.0001), the range of forward flexion (p < 0.05), and abduction strength (p = 0.001) also improved. Thirteen patients (14 shoulders) were very satisfied, ten patients (eleven shoulders) were satisfied, two patients (two shoulders) were disappointed, and three patients (three shoulders) were dissatisfied with the result. The average subjective shoulder value increased from 23% preoperatively to 55% postoperatively (p = 0.0009). In patients with a massive tear, the outcome was less favorable when the torn supraspinatus tendon was irreparable, as determined preoperatively or intraoperatively, than when it was reparable (average relative Constant scores, 49% and 79%, respectively; p = 0.002). CONCLUSIONS: Pectoralis major transfer results in improvement for patients with an irreparable subscapularis tear with or without an associated reparable supraspinatus tear. If an irreparable subscapularis tear is associated with an irreparable supraspinatus tear, the results are less favorable, and pectoralis major transfer may not be warranted.     

Augmented subscapularis muscle transposition for rotator cuff repair during shoulder arthroplasty in patients with rheumatoid arthritis

The effectiveness of rotator cuff repair by augmented subscapularis transposition via the Leeds-Keio artificial ligament was evaluated in patients with rheumatoid arthritis undergoing total shoulder arthroplasty. The minimum follow-up period was 2 years. Final clinical scores (Hospital for Special Surgery scoring system) and the incidence of radiolucency and upward migration of shoulder components in 20 shoulders with rotator cuff repair by augmented subscapularis transposition were superior to those of 19 shoulders with cuff repair by subscapularis transposition alone and similar to those of 22 shoulders with intact rotator cuffs. In shoulders with augmented subscapularis transposition and intact cuffs, clinical scores continued to improve even after the first postoperative year. Our augmented subscapularis transposition did not increase postoperative complications. We conclude that cuff repair by augmented subscapularis transposition is an acceptable alternative for repairing a supraspinatus or supraspinatus and infraspinatus rotator cuff defect in rheumatoid arthritis patients undergoing total shoulder arthroplasty.     

An anatomic evaluation of the active compression test

The goal of this study was to describe the anatomic relationships present during the active compression test. Four pairs of cadaveric shoulders were positioned to simulate the active compression test. The shoulders were embedded in polyurethane and evaluated in the axial and coronal planes with a planer. In the axial plane, all internally rotated shoulders demonstrated contact between the lesser tuberosity and subscapularis tendon and the superior aspect of the glenoid and labrum. In the externally rotated position, there was no contact between the superior structures of the shoulder. In the coronal plane, the internally rotated specimens revealed contact between the supraspinatus tendon and the lateral aspect of the acromion. There was no contact between the supraspinatus tendon and the acromion when the shoulders were externally rotated in the coronal plane. The results demonstrate that the active compression test can be used to assist in the diagnosis of superior labrum anterior-posterior lesions as well as other shoulder pathology.     

Subscapularis,medial, and lateral head coracohumeral ligament insertion anatomy: Arthroscopic appearance and incidence of “hidden” rotator interval lesions

Purpose: The purpose of this study was to document the incidence of lesions of the rotator interval, illustrate the arthroscopic appearance of subtle differences in these lesions, and discuss how various lesions may affect biceps tendon stability in the bicipital groove. Type of Study: A Data Registry has been used in my office since 1995 (Microsoft Office Access). This study reports on the results of a retrospective database “query” of the prospectively entered data from 1995 to 1998. Thus, by default, the format of this study is a consecutive sample. Only patients with a disruption of rotator cuff tendons, labrum and/or gleno-coracohumeral ligaments are included by study design. Methods: This study has identified and reports on 46 arthroscopically identified subscapularis tears, 25 “hidden” rotator interval lesions (SGHL/MCHL complex) and 6 SGHL/CHL complex plastic deformation lesions in 165 patients undergoing shoulder arthroscopy for conditions ranging from anterior instability to rotator cuff tears. Arthroscopically identified lesions include partial or complete disruptions of the subscapularis tendon, disruptions of the superior glenohumeral/medial head coracohumeral ligament complex (SGHL/MCHL), disruptions of the lateral head coracohumeral ligament (LCHL), and various combinations of the above. Results: The incidence rate of subscapularis tendon involvement in 165 arthroscopically treated shoulder patients was 27%. The incidence rate of subscapularis tendon disruptions with rotator cuff pathology was 35%. The incidence rate of SGHL/MCHL lesions (tear or stretch) in 165 arthroscopically treated shoulder patients was 18%. The incidence rate of SGHL/MCHL tears in 165 arthroscopically treated shoulder patients was 15%. Forty-seven percent of all subscapularis tears involved the SGHL/CHL complex. Ten percent of all rotator cuff tears involving the supraspinatus tendon involved the LCHL. Conclusions: This study has recorded the incidence of lesions of the subscapularis, SGHL/MCHL complex and/or the LCHL, and combinations thereof in degenerative cuff and instability patients. Primary lesions of the rotator interval can occur and regardless of the associated pathology, and if these lesions are not repaired, biceps tendon subluxation may exist.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 2 (February), 2001: pp 173–180     

Spontaneous medial dislocation of the tendon of the long biceps brachii. An anatomic study of prevalence and pathomechanics

Medial displacement of the tendon of the long biceps brachii muscle was analyzed in a dissection study on autopsy in 77 subjects, 42 men and 35 women. The tendon was found to be medially displaced in five shoulders in five different subjects (6.5%). Medial displacement of the tendon was always found in connection with full-thickness supraspinatus tendon ruptures. It is a common belief that the tendon is always displaced medially to the lesser tubercle riding over the subscapularis tendon. In the present series, this condition was found only in one case; in the other shoulders the tendon had slipped medially to the lesser tubercle under the subscapularis tendon, which was partially internally ruptured. In patients with rotator cuff lesions, medial displacement of the long biceps tendon might be one reason for pain over the front of the shoulder.     

The sensitivity and specificity of sonographic examination in detection of rotator cuff tear]

Sonographic examination was performed in 72 patients (74 shoulders) suffering from different shoulder diseases. The results were correlated with findings obtained during subsequent surgery in 57 patients (58 shoulders) and arthrography in 15 cases (16 shoulders). Rotator cuff tear was proved during surgical procedure in 37 patients (38 shoulders). The sensitivity and specificity of ultrasonography in detection of cuff tear was 98.2% and 90% respectively. In case of partial cuff tear ultrasonography had lower sensitivity--50% while specificity was 96.3%. In detection of supraspinatus tendon tear the ultrasound sensitivity was 100% and specificity 95.6%, in case of infraspinatus tear sensitivity was 66.7% and specificity 94% while for subscapularis tear these values were equal 75% and 98.1%. The size of sonographically estimated cuff defect correlated properly with intrasurgical measurement in 76.3% of all cases.     

The influence of rotator cuff disease on the results of shoulder arthroplasty for primary osteoarthritis: results of a multicenter study

BACKGROUND: Rotator cuff disease is uncommon in primary glenohumeral osteoarthritis. Consequently, the prognostic implications of rotator cuff disease in patients undergoing prosthetic replacement for the treatment of primary glenohumeral osteoarthritis are uncertain. The purpose of this study was to report the effects of the condition of the supraspinatus tendon and the rotator cuff musculature on the results of shoulder arthroplasty in the treatment of primary osteoarthritis. METHODS: Five hundred and fifty-five shoulders in 514 patients who had an arthroplasty for the treatment of primary glenohumeral osteoarthritis as part of a multicenter study were evaluated. Forty-one shoulders had a partial-thickness tear of the supraspinatus, and forty-two had a full-thickness tear. Ninety shoulders had moderate (stage-2) fatty degeneration of the infraspinatus, and nineteen had severe (stage-3 or 4) degeneration. Eighty-four shoulders had moderate fatty degeneration of the subscapularis, and fifteen had severe degeneration. The influence of the condition of the supraspinatus tendon and the infraspinatus and subscapularis musculature on the postoperative outcome was evaluated with respect to the scores according to the system of Constant and Murley, active mobility, subjective satisfaction, radiographic result, and rate of complications. RESULTS: The shoulders were evaluated at a mean of 43.1 months postoperatively. With the numbers available, supraspinatus tears were not found to influence the postoperative outcome with respect to the total Constant score, active mobility, subjective satisfaction, radiographic result, or rate of complications. Additionally, the treatment of these tears did not markedly influence the outcome parameters. Conversely, both shoulders with moderate fatty degeneration and those with severe degeneration of the infraspinatus were associated with poorer results than those with no degeneration with respect to the total Constant score (p < 0.0005), active external rotation (p < 0.0005), active forward flexion (p = 0.001), and subjective satisfaction (p = 0.031). Similar although less dramatic results were seen with fatty degeneration of the subscapularis. CONCLUSIONS: This study demonstrates that minimally retracted or nonretracted rotator cuff tears that are limited to the supraspinatus tendon do not appreciably affect most shoulder-specific outcome parameters in shoulder arthroplasty performed for the treatment of primary osteoarthritis. Conversely, fatty degeneration of the infraspinatus and, less importantly, subscapularis musculature adversely affects many of these parameters.     

Arthroscopic findings in atraumatic shoulder instability

PurposeThe goal of this study was to evaluate the intra-articular pathology in patients with atraumatic shoulder instability who did not respond to conservative treatment.Type of studyProspective case series.MethodsOf 226 patients treated for shoulder instability over a 2-year-period, 43 patients (average age, 27.5 years; 26 men and 17 women) were classified as having atraumatic instability. None had responded to physiotherapy. The intra-articular pathology was documented during diagnostic arthroscopy before the definitive surgical procedure.ResultsThree types of lesions of the capsulolabral complex were defined: incomplete labral lesions, pathologic elongation of the capsule or “non-Bankart lesions” (type I), classic Bankart lesions (type II), and complex lesions of the labrum and capsule (type III). Type I was found in 19 patients (44.2%); type II lesions were seen in 13 (30.2%); and type III in 11 (25.6%) patients. Hill-Sachs lesions were found in 26 shoulders (60.5%). Chondral lesions of the glenoid were seen in 10 shoulders (23%); SLAP lesions in 5 (11.7%); and partial, articular-side defects of the supraspinatus tendon in 3 (6.9%) patients.ConclusionsAtraumatic onset of shoulder instability does not imply the absence of intra-articular lesions, at least in patients not showing a response to physiotherapy. Arthroscopy is helpful to diagnose the definite intra-articular pathology.Level of evidenceLevel IV.     

切开修补治疗肩袖撕裂的中远期随访

目的 对切开行肩袖修补术的肩袖撕裂患者行中远期随访,分析术前、术中因素对手术疗效的影响.方法 回顾性研究1987年5月至2002年10月在北京医院骨科进行切开手术修补撕裂肩袖的43例患者(44肩).男20例(21肩),女23例(23肩);手术时平均年龄53岁(22～76岁).13肩为小型撕裂(＜1 cm),18肩为中型撕裂(1～3 cm),10肩为大型撕裂(3～5 cm),3肩为巨大型撕裂(＞5 cm).撕裂累及冈上肌31肩,累及冈上肌和冈下肌9肩,累及冈上肌和肩胛下肌3肩,累及冈上肌、冈下肌和肩胛下肌1肩.以Mclaughlin术(肌腱-骨)修补25肩,以肌腱-骨联合肌腱-肌腱缝合法修补11肩,以肌腱-肌腱缝合法修补7肩,三角肌深部肌腱转位术(高岸式)修补1肩.术后平均随访88.2个月(52～250个月),以美国加州大学洛杉矶分校(University of California at Los Angeles,UCLA)功能评分评价患者手术前后的肩关节功能,以视觉模拟评分系统(visual analogue scale,VAS)分析患者对手术效果的主观评价.对患者的年龄、性别、优势手、外伤史、手术前病程和肩袖撕裂大小等因素对预后的影响行统计学分析.结果 44肩UCLA评分术前平均为(11.5±2.8)分,末次随访时平均为(29.7±5.3)分.36肩得分＞28分,达到优或良;6肩为可;2肩得分＜20分,评定为差.患者对39肩的手术疗效满意,主观满意率89%.患者主观满意度与UCLA评分呈显著正相关(r=0.72,P＜0.01).肩袖撕裂的大小(r=-0.404,P=0.007)、术前病程(r=-0.332,P=0.028)与术后结果呈负相关,即肩袖撕裂范围越大、术前病程越长,手术疗效就越差.而手术患者的年龄、性别、优势手、外伤史与手术的预后无关.结论 切开修补治疗肩袖全层撕裂能获得满意的中远期疗效,肩袖的撕裂大小、术前病程与术后结果呈负相关.     

Tears of the supraspinatus tendon associated with "hidden" lesions of the rotator interval

Exploration of the rotator interval during repair of 116 apparently "isolated" supraspinatus tendon lesions have revealed "hidden lesions" of the coracohumeral ligament, the superior glenohumeral ligament, and the superior portion of the subscapularis tendon in 19 cases. Epidemiologic characteristics were comparable with other series with the exception of involvement of the dominant shoulder in 95%. Arthroscopic computed tomography documented the lesion in 85% of the cases. At surgery the superficial layer of the coracohumeral ligament was always intact. After splitting of the rotator interval the lesion was visible and consisted of a local disinsertion of the common insertion of the superior glenohumeral ligament and the coracohumeral ligament and the deep superior fibers of the subscapularis tendon. It measured 1 to 2 cm in the superior-inferior direction. The biceps tendon was ruptured in 2 cases, subluxated in 14, and in its normal position in 5. The treatment consisted of intraosseous reinsertion of the supraspinatus tendon, recentering of the biceps, and reinsertion of the torn structures to reconstruct a functional pulley system. The patients have been reviewed with a mean follow-up of 20 months (range 12 to 36 months). A secondary rupture of the long head of the biceps has been observed in 25% of the cases after recentering of the tendon.     

Subscapularis muscle function and structure after total shoulder replacement with lesser tuberosity osteotomy and repair

BACKGROUND: Recent studies have suggested that tenotomy and repair of the subscapularis tendon carried out for anterior approaches to the shoulder can be followed by failure of the tendon repair and by changes resulting in permanent loss of subscapularis function. We hypothesized that release of the subscapularis with use of a superficial osteotomy of the lesser tuberosity followed by repair of the two opposing bone surfaces would lead to consistent bone-to-bone healing, which would be possible to monitor radiographically, and would lead to satisfactory clinical and structural outcomes. METHODS: Thirty-nine shoulders in thirty-six consecutive patients who, at an average age of fifty-seven years, had undergone total shoulder replacement through an anterior approach involving an osteotomy of the lesser tuberosity were evaluated at an average of thirty-nine months. Assessment included a standardized interview and physical examination, scoring according to the system described by Constant and Murley, and imaging with conventional radiography and computed tomography to assess healing of the osteotomy site and changes in the subscapularis. RESULTS: The osteotomized tuberosity fragment healed in an anatomical position in all shoulders, and no cuff tendon ruptures were observed. At the time of follow-up, thirty-three (89%) of thirty-seven shoulders evaluated with a belly-press test had a negative result and twenty-seven (75%) of thirty-six shoulders evaluated with a lift-off test had an unequivocally normal result. Fatty infiltration of the subscapularis muscle increased after the operation (p < 0.0001) and was at least stage two in eleven (32%) of thirty-four shoulders. The fatty infiltration had progressed by one stage in eight (24%) of the thirty-four shoulders, by two stages in five shoulders (15%), and by three stages in two shoulders (6%). CONCLUSIONS: Osteotomy of the lesser tuberosity provides an easy anterior approach for total shoulder replacement and is followed by consistent bone-to-bone healing, which can be monitored, and good subscapularis function. In the presence of documented anatomical healing of the osteotomy site, postoperative fatty infiltration of the subscapularis muscle remains unexplained and needs to be investigated further as it is associated with a poorer clinical outcome.     

Transfer of the pectoralis major muscle for the treatment of irreparable rupture of the subscapularis tendon

BACKGROUND: The clinical diagnosis of a tear of the subscapularis tendon is difficult, and the resulting delays frequently cause a major time-lapse before repair is attempted. Diagnostic delay often means that surgical repair is no longer possible. In twelve patients who had an irreparable tear of the subscapularis tendon, the superior one-half to two-thirds of the tendon of the pectoralis major muscle was used as a substitute for the subscapularis tendon. In order to adapt the orientation of the transferred muscle to that of the subscapularis, it was routed behind the conjoined tendon of the coracobrachialis muscle and the short head of the biceps to the lesser tuberosity. METHODS: The operations were performed between May 1993 and June 1997. The average age of the twelve patients was sixty-five years old (range, forty-nine to eighty-one years old). Eight patients had an isolated rupture of the subscapularis tendon, and four had a concomitant lesion in the form of either a partial or a complete rupture of the supraspinatus tendon. The dominant symptoms were anterior shoulder pain and weakness that had responded poorly to nonoperative therapy. Four patients also had signs of recurrent anterior instability. RESULTS: After an average follow-up interval of twenty-eight months (range, twenty-four to fifty-four months), nine of the twelve patients assessed the final result as excellent or good; three, as fair; and none, as poor. Pain was reduced, with the score improving from an average of 1.7 points (of a maximum of 15 points) preoperatively to an average of 9.6 points postoperatively. The patients' subjective functional evaluation improved from an average score of 20 points preoperatively to an average of 63 points postoperatively. The average functional rating with use of the Constant and Murley score increased from 26.9 to 67.1 percent of normal. All four preoperatively unstable shoulders were stable at the time of the latest follow-up. CONCLUSIONS: This repair technique can be recommended as a reconstructive procedure for elderly patients who have an irreparable tear of the subscapularis tendon.     

Rotator cuff strength following open subscapularis tendon repair

The purpose of this study was to evaluate supraspinatus and subscapularis strength following repair of either isolated or anterosuperior subscapularis tears associated with a supraspinatus tear. Open subscapularis repairs were done in 24 patients, 12 isolated and 12 anterosuperior. At an average follow-up of 40 months, UCLA, ASES, and Constant scores were recorded. Subscapularis and supraspinatus strengths were tested using a spring gauge. Ultrasound scanning was performed in 20 patients. Average scores were 27 UCLA, 77 ASES and 90 relative Constant. Subscapularis strength was 92% of the non-operated shoulder. Supraspinatus strength was 90%. Statistical analysis showed a significant decrease in supraspinatus strength in the anterosuperior group. No other significant differences were noted. Ultrasound scanning showed an intact subscapularis tendon in all. Full thickness supraspinatus tears were found in 5 and partial thickness in 1. Not the subscapularis, but the supraspinatus determines the outcome of anterosuperior repairs, with more re-tears and decreased strength.     

肩袖损伤的诊断要点与手术治疗

目的探讨肩袖损伤的临床诊断及手术治疗方法,评价手术治疗效果,验证MRI表现与术中所见的差异。方法102例肩袖损伤手术均由同一医师主刀完成,采用肩关节外侧微创切口,切除喙肩韧带,肩峰成形,探查修整肩袖,褥式缝合冈上肌、冈下肌及肩胛下肌,术后外展石膏固定。结果102例均得到半年以上随访,采用UCLA评分系统评价,优44例,良56例,差2例,术后疼痛改善率98·04%,几乎所有患者对疼痛改善满意。结论手术微创切口治疗肩袖损伤是一种行之有效的治疗方法,手术创伤小、视野良好,术后功能好,疼痛消除明显,值得临床推广运用。     

Anterosuperior impingement of the shoulder as a result of pulley lesions: a prospective arthroscopic study

Lesions of the biceps pulley and the rotator cuff have been reported to be associated with an internal anterosuperior impingement (ASI) of the shoulder. The purpose of this study was to determine the factors influencing the development of an ASI. Eighty-nine patients with an arthroscopically diagnosed pulley lesion were prospectively included in this study. Four patterns of intraarticular lesions could be identified. Twenty-six patients (group 1) showed an isolated lesion of the superior glenohumeral ligament (SGHL). In 21 patients (group 2) an SGHL lesion and a partial articular-side supraspinatus tendon tear were found. Twenty-two patients (group 3) had an SGHL lesion and a deep surface tear of the subscapularis tendon, and in twenty patients (group 4) a lesion of the SGHL combined with a partial articular-side supraspinatus and subscapularis tendon tear was diagnosed. Of the patients, 80 (89.9%) showed involvement of the long head of the biceps tendon including synovitis, subluxation, dislocation, and partial or complete tearing. In 43.8% of all patients, ASI was observed. Whereas ASI was seen in 26.6% and 19.1% of patients in groups 1 and 2, respectively, 59.1% of patients in group 3 and 75% of patients in group 4 were found to have an ASI. ASI was significantly more often seen in patients with additional partial articular-side subscapularis tendon tears (P <.0001). In patients with acromioclavicular (AC) arthritis, ASI (62.5%) was more frequently observed than in patients without AC arthritis (P =.0309). In the multivariate analysis the stepwise selection procedure revealed only AC arthritis and the deep surface tear of the subscapularis (groups 3 and 4) to be significant influencing factors for an ASI. Our findings indicate that a progressive lesion of the pulley system, including partial tears of the subscapularis and supraspinatus tendons, contributes significantly to the development of an ASI. A pulley lesion leads to instability of the long head of the biceps tendon, causing increased passive anterior translation and upward migration of the humeral head, resulting in an ASI. In addition, a partial articular-side subscapularis and supraspinatus tendon tear reinforces the ASI.     

Shoulder electromyography in multidirectional instability

We studied shoulder muscle activity in multidirectional instability (MDI) and multidirectional laxity (MDL) of the shoulder, our hypothesis being that altered muscle activity plays a role in their pathogenesis. Six muscles (supraspinatus, infraspinatus, subscapularis, anterior deltoid, middle deltoid, and posterior deltoid) were investigated by use of intramuscular dual fine-wire electrodes in 7 normal shoulders, 5 MDL shoulders, and 6 MDI shoulders. Each subject performed 5 types of exercise (rotation in neutral, 45 degrees of abduction, 90 degrees of abduction, flexion/extension, and abduction/adduction) on an isokinetic muscle dynamometer at two rates, 90 degrees /s and 180 degrees /s. After filtering, rectification, and smoothing, the electromyography signal was normalized by using the peak voltage of the movement cycle. In subjects with MDI, compared with normal subjects, activity patterns of the anterior deltoid were different during rotation in neutral and 90 degrees of abduction, whereas those of the middle and posterior deltoid were different during rotation in 90 degrees of abduction. In subjects with MDL, the posterior deltoid showed increased activity compared with normal subjects during adduction. Activity patterns of the supraspinatus, infraspinatus, and subscapularis appeared similar in both groups. Dual fine-wire electromyography offers insight into the complex role of shoulder girdle muscle function in normal movement and in instability. Altered patterns of shoulder girdle muscle activity and imbalances in muscle forces support the theory that impaired coordination of shoulder girdle muscle activity and inefficiency of the dynamic stabilizers of the glenohumeral joint are involved in the etiology of MDI. Interestingly, the abnormalities are in the deltoid rather than the muscles of the rotator cuff.     

Occult fractures of the greater tuberosity of the humerus

We studied the highest reported number of patients with occult fracture of the greater tuberosity of the humerus and we analysed why fracture was not diagnosed, shoulder function and prevalence of eventually associated rotator cuff tear (RCT). Twenty-four patients with a missed fracture of the greater tuberosity underwent MR study for a suspect RCT. We evaluated shoulder function and self-assessed comfort with the Constant score (CS) and Simple Shoulder Test (SST). Nine patients showed evidence of cuff tendinosis, 11 of partial (p) RCT (2: subscapularis; 6: supraspinatus and 3: supraspinatus and infraspinatus). All patients with pRCT were older than 40. Initially, the mean CS and SST were 54% and 5/12; at follow-up, values increased to 36% and 5 points. MR should be performed in patients apparently negative for fracture but with painful shoulders and decreased ROM. Of our patients, 45.8% had pRCT; nevertheless function recovery was verified in 16 weeks.     

Biceps tendon and superior labral injuries

Twenty-two patients sustained injury to the biceps tendon, rotator cuff interval, or superior labrum. Seven patients with "interval lesions" underwent biceps tenodesis, one biceps repair, and three subscapularis repairs. All were satisfied, although one tenodesis failed with distal biceps retraction. Key arthroscopic findings included biceps or subscapularis fraying. Thirteen patients with "S.L.A.P. (superior labrum anterior to posterior) lesions" underwent labral debridement. All but one obtained pain relief. Eight cadaveric shoulders exhibited extreme anatomic variability of the bicipital origin/superior labral attachment. Biomechanical study showed anterior-superior and posterior-superior labral strain with simulated biceps contraction to be greatest in shoulder abduction (p < 0.01). Biceps tendon strain was greatest in shoulder adduction (p < 0.05). A continuum of injuries to the biceps tendon exist, from the rotator cuff interval to the labral attachment. Key arthroscopic findings may assist in the difficult diagnosis of interval lesions. Individual anatomy and mechanism of injury may determine the site of the lesion.