Satisfaction, function and repair integrity after arthroscopic versus mini-open rotator cuff repair.

AIMS: Advances in arthroscopic techniques for rotator cuff repair have made the mini-open approach less popular. However, the mini-open approach remains an important technique for repair for many surgeons. The aims of this study were to compare the integrity of the repair, the function of the shoulder and satisfaction post-operatively using these two techniques in patients aged > 50 years. PATIENTS AND METHODS: We identified 22 patients treated with mini-open and 128 patients treated with arthroscopic rotator cuff repair of July 2007 and June 2011. The mean follow-up was two years (1 to 5). Outcome was assessed using the American Shoulder and Elbow Surgeons (ASES) and Simple Shoulder Test (SST) scores, and satisfaction. The integrity of the repair was assessed using ultrasonography. A power analysis ensured sufficient enrolment. RESULTS: There was no statistically significant difference between the age, function, satisfaction, or pain scores (p > 0.05) of the two groups. The integrity of the repair and the mean SST scores were significantly better in the mini-open group (91% of mini-open repairs were intact versus 60% of arthroscopic repairs, p = 0.023; mean SST score 10.9 (standard deviation (sd) 1.3) in the mini-open group; 8.9 (sd 3.5) in arthroscopic group; p = 0.003). The ASES scores were also higher in the mini-open group (mean ASES score 91.0 (sd 10.5) in mini-open group; mean 82.70 (sd 19.8) in the arthroscopic group; p = 0.048). CONCLUSION: The integrity of the repair and function of the shoulder were better after a mini-open repair than after arthroscopic repair of a rotator cuff tear in these patients. The functional difference did not translate into a difference in satisfaction. Mini-open rotator cuff repair remains a useful technique despite advances in arthroscopy. Cite this article: Bone Joint J 2017;99-B:245-9.

Age-related changes of the glenoid labrum in normal shoulders.

A growing number of labral changes are described in the literature. The purpose of this study was to evaluate the glenoid and labrum of normal shoulders at different ages and characterize any apparent age-dependent changes. We analyzed 32 normal cadaveric shoulders with a mean age of 57 years (range, 18-89 years). There were 22 male and 10 female cadavers, with 14 right and 18 left specimens. The shoulders were studied macroscopically, histologically, and radiologically. The radiologic evaluation consisted of an analysis of the subchondral mineralization of the glenoid with the use of computed tomographic osteoabsorptiometry. Macroscopically, there were no statistically significant differences among the age groups. Histopathologically, the labrum showed a significant qualitative and quantitative increase (P <.01) in lesions across all regions with increasing age. In younger individuals, lesions at the 12-o'clock position were the most prevalent, with the incidence increasing with age. The anterosuperior position was the region with the next highest prevalence. This was also the area of the highest stress distribution on the glenoid. Our studies demonstrated clear histopathologic changes of the glenoid labrum that are significantly age-related at specific sites. The earliest changes are seen close to the area of highest stress distribution of the glenoid, which could explain the progressive labral changes with increasing age. Arthroscopically detected changes of the glenoid labrum should be evaluated in the context of age-related changes in normal shoulders.

Revision rotator cuff repair: factors influencing results.

BACKGROUND: Revision rotator cuff repair is a surgical challenge, and the results have generally been inferior to those of primary repair. We examined the results of revision rotator cuff repair in a large series of patients and assessed which subgroups of patients had the greatest chance for a satisfactory functional outcome. METHODS: A revision rotator cuff repair was performed in eighty patients after the failure of a previous operative repair. The average age of the patients at the time of the revision was fifty-nine years. Prior to revision, the average pain score was 7.4 points (with 0 points indicating no pain and 10 points, severe pain) and the active range of motion of the shoulder averaged 105 degrees of elevation, 39 degrees of external rotation, and internal rotation to the eleventh thoracic vertebra. All patients underwent repeat repair of the rotator cuff tendons to bone. Additional procedures included revision acromioplasty (fifty-three patients; 66%) and distal clavicular excision (twenty-six patients; 33%), among others. RESULTS: After an average duration of follow-up of forty-nine months, the result was rated as satisfactory (excellent, good, or fair) in fifty-five patients (69%) and as unsatisfactory (poor) in twenty-five (31%). At the time of the latest follow-up, the average pain score had improved to 3.0 points and the active range of motion averaged 130 degrees of elevation, 53 degrees of external rotation, and internal rotation to the tenth thoracic vertebra. Improved results were associated with an intact deltoid origin, good-quality rotator cuff tissue, preoperative active elevation of the arm above the horizontal, and only one prior procedure. All seventeen patients who met all four of these criteria had a satisfactory result. CONCLUSIONS: The results of revision rotator cuff repair are inferior to those of primary repair. While pain relief can be reliably achieved in most patients, the functional results are improved principally in patients with an intact deltoid origin, good-quality rotator cuff tissue, preoperative elevation above the horizontal, and only one prior procedure.

Technique of open rotator cuff repair.

With current surgical techniques, open rotator cuff repair can provide significant functional improvement and pain relief in the majority of patients. Important principles include performing anterior acromioplasty, bursal resection, rotator cuff mobilization, tension-free repair to the greater tuberosity with nonabsorbable sutures, and meticulous deltoid repair. In massive rotator cuff tears, the coracoacromial ligament should be repaired to prevent anterosuperior instability, and partial repair of the rotator cuff is recommended over performing transfer procedures. Postoperative rehabilitation requires the patient to avoid active exercises for 6 weeks and weights for 3 months. With these techniques, 85% to 90% satisfactory results can be expected.

Glenohumeral mechanics: a study of articular geometry, contact, and kinematics.

Stereophotogrammetry was used to investigate the functional relations between the articular surface geometry, contact patterns, and kinematics of the glenohumeral joint. Nine normal shoulder specimens were elevated in the scapular plane by using simulated muscle forces in neutral rotation (NR) and starting rotation (SR). Motion was quantified by analyzing the translations of the geometric centers of the humeral head cartilage and bone surfaces relative to the glenoid surface. In both NR and SR, the ranges of translations of the center of the humeral head cartilage surface were greatest in the inferior-superior direction (NR 2.0 +/- 0.7 mm, SR 2.9 +/- 1.2 mm). Results of this study also show that joints with less congruence of the articular surfaces exhibit larger translations, and elevation in SR yields greater translations than in NR. Kinematic analyses with the humeral head bone surface data yielded larger values of translation than analyses that used the cartilage surface data, suggesting that similar overestimations may occur in radiographic motion studies. Results of this study demonstrate that small translations of the humeral head center occurred in both SR and NR. The proximity of the origin of the helical axes to the geometric center of the humeral head articular surface confirmed that glenohumeral elevation is mainly rotation about this geometric center with small translations.

Effects of repetitive subfailure strains on the mechanical behavior of the inferior glenohumeral ligament.

The mechanical response of the inferior glenohumeral ligament to varying subfailure cyclic strains was studied in 33 fresh frozen human cadaver shoulders. The specimens were tested as bone-ligament-bone preparations representing the 3 regions of the inferior glenohumeral ligament (superior band and anterior and posterior axillary pouches) through use of uniaxial tensile cycles. After mechanical preconditioning, each specimen was subjected to 7 test segments, consisting of a baseline strain level L1 (400 cycles) alternating with either 1 (group A, 10 shoulders), 10 (group B, 13 shoulders), or 100 (group C, 10 shoulders) cycles at increasing levels (L2, L3, L4) of subfailure strain. Cycling to higher levels of subfailure strain (L2, L3, L4) produced dramatic declines in the peak load response of the inferior glenohumeral ligament for all specimens. The group of ligaments subjected to 100 cycles of higher subfailure strains demonstrated a significantly greater decrease in load response than the other 2 groups. Ligament elongation occurred with cyclic testing at subfailure strains for all 3 groups, averaging 4.6% +/- 2.0% for group A, 6.5% +/- 2.6% for group B, and 7.1% +/- 3.2% for group C. Recovery of length after an additional time of nearly 1 hour was minimal. The results from this study demonstrate that repetitive loading of the inferior glenohumeral ligament induces laxity in the ligament, as manifested in the peak load response and measured elongations. The mechanical response of the ligament is affected by both the magnitude of the cyclic strain and the frequency of loading at the higher strain levels. The residual length increase was observed in all of the specimens and appeared to be largely unrecoverable. This length increase may result from accumulated microdamage within the ligament substance, caused by the repetitively applied subfailure strains. The clinical relevance of the study is that this mechanism may contribute to the development of acquired glenohumeral instability, which is commonly seen in the shoulders of young athletes who participate in repetitive overhead sports activities.

Anterior and posterior musculotendinous anatomy of the supraspinatus.

The objective of this study was to quantitatively describe the supraspinatus musculotendinous architecture. After supraspinatus muscles were harvested from 25 embalmed shoulders, each muscle was divided into an anterior and posterior muscle belly on the basis of muscle fiber insertion. Pennation angles and musculotendinous dimensions were measured, and the physiologic cross-sectional area was calculated for each muscle belly. The physiologic cross-sectional areas of the anterior and posterior bellies were calculated to be 140 +/- 43 mm2 and 62 +/- 25 mm2, respectively, whereas their tendon cross-sectional areas were 26.4 +/- 11.3 mm2 and 31.2 +/- 10.1 mm2, respectively. The average anterior-to-posterior ratios for the muscle physiologic cross-sectional area and the tendon cross-sectional area were 2.45 +/- 0.82 and 0.87 +/- 0.30, respectively. Thus, a larger anterior muscle pulls through a smaller tendon area. These data suggest that physiologically, anterior tendon stress is significantly greater than posterior tendon stress and that rotator cuff tendon repairs should incorporate the anterior tendon whenever possible, inasmuch as it functions as the primary contractile unit.

Three-dimensional analysis of the proximal part of the humerus: relevance to arthroplasty.

BACKGROUND: Recreation of normal anatomical relationships may be important to optimize the outcome of proximal humeral arthroplasty. With use of computerized tomographic data and three-dimensional computer modeling, we concurrently studied both extramedullary and intramedullary humeral morphology, including canal shape, and related these findings to the design of proximal humeral prostheses. METHODS: Sixty cadaveric humeri (thirty pairs: fifteen from male donors and fifteen from female donors) were studied. Three-dimensional computer models were built from canal and periosteal contours extracted from computerized tomographic data and multiple measured anatomical parameters, including humeral canal axis, humeral head center, and hinge point offset; greater tuberosity and bicipital groove offset; humeral head center, radius, thickness, retroversion, and inclination; and size and torsion of sections of the canal. RESULTS: On the average, the humeral head center was offset both medially (seven millimeters) and posteriorly (two millimeters) from the humeral axis. The humeral head hinge point did not line up with the axis but instead was laterally offset by an average of seven millimeters. The average humeral head thickness was nineteen millimeters. The humeral head thickness and length were proportionately linked. There was marked variability in all of these parameters. Humeral head inclination averaged 41 degrees but was less variable than previously described, with 95 percent of our sample within the range of 35 to 46 degrees. The proximal section of the humeral canal was retroverted, and the retroversion was found to be similar to that of the humeral head on statistical analysis. Version of the middle and distal sections of the canal, however, was dissimilar to that of the proximal section of the canal. Proximal humeral retroversion was found to be extremely variable and averaged 19 degrees. The accuracy, reliability, and repeatability of the computer-based-model measurements were found to be excellent. CONCLUSIONS: Measurements of external proximal humeral morphology made with three-dimensional computer models of cadaveric specimens derived from the Midwestern United States agreed, in general, with those described for different populations evaluated with different measuring techniques. Proximal humeral morphology was extremely variable as highlighted by the large ranges of measurements seen for all variables. Examination of the intramedullary morphology showed that there is an internal version, with measurements dependent on the canal distance distal to the anatomical neck. CLINICAL RELEVANCE: Because of the marked variabilities seen in proximal humeral morphology, newer prosthetic designs are now allowing surgeons to control multiple prosthetic variables. An understanding of the normal values for proximal humeral morphology can serve as an important guideline for component selection, especially when the normal anatomy is distorted. Additionally, variations in intramedullary version may have important consequences for future designs of press-fit proximal humeral replacement.

Osteolysis of the distal clavicle: long-term results of arthroscopic resection.

PURPOSE: The purpose of this study was to evaluate the outcome of arthroscopic distal clavicle resection by the direct superior approach for treatment of isolated osteolysis of the distal clavicle. TYPE OF STUDY: Case series. MATERIALS AND METHODS: Forty-one shoulders in 37 patients underwent arthroscopic resection of the distal clavicle. Thirty-three patients were male and 4 female, with an average age of 39 years. All patients complained of pain localized to the acromioclavicular joint region. Symptoms began after a traumatic event in 18 shoulders and were associated with repetitive stressful activity in 23 shoulders. RESULTS: At an average follow-up of 6.2 years, 22 shoulders had excellent results, 16 had good results, and 3 were failures. All 3 failures occurred in patients with a traumatic etiology. CONCLUSIONS: Arthroscopic resection for osteolysis of the distal clavicle has results comparable to open excision with low morbidity. Patients with a traumatic etiology had slightly worse results compared with patients with a microtraumatic etiology.

Indwelling interscalene catheter anesthesia in the surgical management of stiff shoulder: a report of 100 consecutive cases.

One hundred consecutive stiff shoulders in 93 patients resistant to conservative therapy were treated with surgery and intermittent regional anesthesia via indwelling interscalene catheter. Each patient underwent manipulation and one of several operative treatments to release any additional contracture. The indwelling interscalene catheter remained in place and functioned well for an average of 3 days in 87 shoulders. At an average follow-up of 3.0 years, overall clinical results according to Neer's criteria were excellent in 39 shoulders (39%), satisfactory in 28 (28%), and unsatisfactory in 33 (33%). Patients reported no or mild pain in 83 (83%) of the shoulders in the study. At final follow-up, average gains in motion were 44 degrees of elevation (115 degrees to 159 degrees), 31 degrees of external rotation (22 degrees to 53 degrees), and 5 spine segments of internal rotation (L4 to T11). At final follow-up, 95% of the elevation and 79% of the external rotation achieved intraoperatively were maintained. The best results were obtained in those shoulders with idiopathic stiffness (88% excellent or satisfactory results); the worst results were in the postsurgical shoulders (47% excellent or satisfactory results). There were no catheter-related complications. The use of an indwelling interscalene catheter for postoperative pain control is a safe technique that facilitates early physical therapy in a patient population with a high risk of developing recurrent stiffness.

Operative results of the inferior capsular shift procedure for multidirectional instability of the shoulder.

BACKGROUND: Neer and Foster previously described the inferior capsular shift procedure for treating multidirectional instability of the shoulder and reported preliminary results that were quite satisfactory. The purpose of our study was to perform a longer-term follow-up evaluation of the efficacy of the inferior capsular shift procedure for treating multidirectional instability of the shoulder. METHODS: An inferior capsular shift procedure was used to treat multidirectional instability of the shoulder in forty-nine patients (fifty-two shoulders). All patients had failed to respond to an exercise program. In this series, the operative approach (anterior or posterior) was based on the major direction of the instability, as determined by the preoperative history and physical examination and as verified by examination with the patient under anesthesia. In all of the patients, the inferior capsular shift was the primary attempt at operative stabilization. The repair consisted of a lateral-side (or humeral-side) shift of the capsule to reduce capsular redundancy and, when necessary, a reattachment of the avulsed labrum to the anteroinferior aspect of the glenoid. RESULTS: A redundant capsular pouch was seen in all of the shoulders in this series. In addition, detachment of the anteroinferior aspect of the labrum was found in ten shoulders and an anterior fracture of the glenoid rim was seen in two shoulders. At an average of sixty-one months (range, twenty-four to 132 months), results were available for forty-nine shoulders (forty-six patients). Thirty shoulders (61 percent) had an excellent overall result, sixteen (33 percent) had a good result, one (2 percent) had a fair result, and two (4 percent) had a poor result. Forty-seven (96 percent) of the forty-nine shoulders remained stable at the time of follow-up. Two of the thirty-four shoulders that had been repaired through an anterior approach began to subluxate anteroinferiorly again. None of the fifteen shoulders that had been repaired through a posterior approach had recurrent instability. Full function, including the ability to perform strenuous manual tasks, was restored to forty-five shoulders (92 percent). A return to sports was possible after thirty-one (86 percent) of the thirty-six procedures done in athletes; however, a return to the premorbid level of participation was possible after only twenty-five (69 percent) of the thirty-six procedures. CONCLUSIONS: The results in this series demonstrate the efficacy and the durability of the results of the inferior capsular shift procedure for the treatment of shoulders with multidirectional instability. The procedure directly addresses the major pathological feature - a redundant joint capsule. Similar results were seen with either an anterior or a posterior approach, and we continue to approach shoulders with multidirectional instability on the side of greatest instability. A postoperative brace was reserved for patients in whom a posterior approach had been used or in whom an anterior approach had involved extensive posterior capsular dissection (ten of the thirty-four shoulders treated with the anterior approach).

Arthroscopic debridement of the shoulder for osteoarthritis.

Twenty-five patients underwent arthroscopic debridement to treat early glenohumeral osteoarthritis. The group consisted of 19 men and 6 women with an average age of 46 years (range, 27 to 72 years.) The operative procedure consisted of lavage of the glenohumeral joint, debridement of labral tears and chondral lesions, loose body removal, and partial synovectomy and subacromial bursectomy. Follow-up averaged 34 months, with a range of 12 to 63 months. Overall, results were rated as excellent in 2 patients (8%), good in 19 patients (72%), and unsatisfactory in 5 (20%). Two patients had complete relief of pain, 18 patients had only occasional mild pain, and 5 had moderate to severe pain postoperatively. Of the 12 patients with marked preoperative stiffness, 10 (83%) had improvement in range of motion postoperatively. Arthroscopic debridement is a reasonable approach for treating early glenohumeral osteoarthritis that has failed to respond to nonoperative treatment, in which the humeral head and glenoid remain concentric, and where there is still a visible joint space on an axillary radiograph. The procedure is not recommended when there is severe joint incongruity or large osteophytes.

Comparison of arthroscopic and open revision decompression for failed anterior acromioplasty.

Thirty-six consecutive patients who underwent revision decompression for refractory subacromial impingement were studied retrospectively. Average interval from the primary decompression procedure to revision was 29 months. Eighteen patients underwent arthroscopic and 18 underwent open revision. Six (33%) patients in the arthroscopic group and 12 (67%) patients in the open group were workers' compensation cases. At an average follow-up of 26 months, 17 (94%) patients in the arthroscopic group and 8 (44%) in the open group were satisfied with their procedure. Comparing workers' compensation patients, 5 of 6 in the arthroscopic group and 4 of 12 in the open group were satisfied. For nonworkers' compensation patients, all 12 patients in the arthroscopic group and 4 of 6 in the open group were satisfied. Average pain scores and postoperative range of motion was improved in both groups. Dense subacromial scarring with thick, fibrous adhesions was present in all patients. Residual, prominent bone, or an acromial spur was found in 20 (56%) patients. Overall, revision arthroscopic subacromial decompression was superior to open revision. However, there were more workers' compensation patients in the open group. Workers' compensation patients fared worse for both groups, but a significant proportion (83%) of the arthroscopic group was satisfied. Since subacromial scarring may be the most important pathology, arthroscopy is less invasive, allowing earlier, unrestricted postoperative rehabilitation and proving more effective.

Portal-extension approach for the repair of small and medium rotator cuff tears.

One hundred ten consecutive cases (110 patients) of arthroscopically assisted rotator cuff repair through a limited, portal-extension approach were retrospectively reviewed. The average age of our patients was 58 years (range, 30 to 79). There were 35 women and 75 men. The dominant shoulder was affected in 67 patients (61%). All patients underwent a standard arthroscopic decompression. Acromioclavicular resections were performed in 15% of patients. The anterolateral portal was extended in the direction of Langer's lines to a total length of no more than 3 cm. The torn tendon was accessed through a small deltoid muscle split and repaired with nonabsorbable sutures. At an average follow-up of 35 months (range, 24 to 86), 106 patients (96%) had achieved excellent or satisfactory results. The average American Shoulder and Elbow Surgeons pain score improved from 7 preoperatively to 2 postoperatively. All but four patients were satisfied with the clinical result and reported significant improvement in active elevation and strength and a significant lessening of pain. Late acromioclavicular joint pain contributed to failure in three of the four patients with unsatisfactory results in this series. The results of this study suggest that, in selected patients with small to medium rotator cuff tears, arthroscopically assisted repair through an anterolateral portal-extension approach can produce excellent results.

Rotator cuff tears and associated nerve injuries.

A series of 15 patients with concomitant rotator cuff tears and infraclavicular brachial plexus injuries treated between 1980 and 1989 were reviewed. There were 6 men and 9 women with a mean age of 65 years. Seventeen nerve injuries were identified, including 12 axillary nerves, 4 suprascapular nerves, and 1 musculocutaneous nerve. One patient had an injury to all three nerves. Thirteen patients underwent operative repair of the torn rotator cuff, and 2 patients who refused surgery were treated conservatively. The average time from injury to surgery was 7.7 months. Follow-up averaged 5.5 years (range: 2-10 years). Clinical results were graded according to pain, range of motion, and strength. Postoperatively, mean active forward elevation was 137 degrees and mean active external rotation was 40 degrees. Clinically, 8 patients achieved complete nerve recovery and 7 had an incomplete recovery. Satisfactory pain relief was achieved in 87% of patients with 60% having excellent or good function. Overall, the results of rotator cuff repair with concurrent nerve injury are less favorable than those of isolated cuff repairs. Careful preoperative assessment of concomitant nerve injury should be performed to better predict outcome.

Open revision stabilization surgery for recurrent anterior glenohumeral instability.

Fifty patients (average age, 27 years) who underwent revision anterior stabilization surgery for failed anterior glenohumeral instability procedures were retrospectively reviewed. Failure of the original procedure occurred subsequent to significant trauma in only 17 of 50 shoulders. At revision, 49 shoulders underwent an anteroinferior capsular shift procedure and 23 underwent concurrent repair of a Bankart lesion. One shoulder was treated with a coracoid transfer to reconstruct the anteroinferior glenoid. At an average follow-up of 4.7 years (range, 2 to 10), there were 36 excellent and 3 good results (78%). Eleven shoulders were considered unsatisfactory (22%); 7 of these 11 patients had a diagnosis of voluntary dislocation. All 17 patients who had failed results after significant trauma had excellent results after revision surgery. However, only 22 of the 33 patients (67%) with atraumatic recurrent instability achieved excellent or good results after revision surgery. This difference was statistically significant. No patients had radiographic evidence of osteoarthritis at the most recent follow-up. Range of motion, return to function, and glenohumeral stability can be reliably restored in a high percentage of patients after revision anterior stabilization surgery for glenohumeral instability. However, the results are not as predictable as for primary surgery. Factors associated with poor results of revision repair included an atraumatic cause of failure, voluntary dislocations, and multiple prior stabilization attempts.

Complications with humeral head replacement.

Humeral head replacement has been shown to be an excellent surgical option for a variety of debilitating shoulder conditions. New techniques and advances in prosthetic design have furthered the success of this procedure. When performed without appropriate indications, exacting technique, and a tailored rehabilitation program, however, complications often result. Early recognition and appropriate management of these complications aid in achieving a satisfactory result.

Spinal accessory nerve injury.

Injury to the spinal accessory nerve can lead to dysfunction of the trapezius. The trapezius is a major scapular stabilizer and is composed of three functional components. It contributes to scapulothoracic rhythm by elevating, rotating, and retracting the scapula. The superficial course of the spinal accessory nerve in the posterior cervical triangle makes it susceptible to injury. Iatrogenic injury to the nerve after a surgical procedure is one of the most common causes of trapezius palsy. Dysfunction of the trapezius can be a painful and disabling condition. The shoulder droops as the scapula is translated laterally and rotated downward. Patients present with an asymmetric neckline, a drooping shoulder, winging of the scapula, and weakness of forward elevation. Evaluation should include a complete electrodiagnostic examination. If diagnosed within 1 year of the injury, microsurgical reconstruction of the nerve should be considered. Conservative treatment of chronic trapezius paralysis is appropriate for older patients who are sendentary. Active and healthy patients in whom 1 year of conservative treatment has failed are candidates for surgical reconstruction. Studies have shown the Eden-Lange procedure, in which the insertions of the levator scapulae, rhomboideus minor, and rhomboideus major muscles are transferred, relieves pain, corrects deformity, and improves function in patients with irreparable injury to the spinal accessory nerve.

The teres major muscle: an anatomic study of its use as a tendon transfer.

Eleven fresh-frozen cadaver shoulders were dissected to define the anatomy of the teres major muscle and tendon and to determine the muscle's potential for use as a tendon transfer to the humeral head. Of the 11 specimens, 7 had Mathes type II circulation. The primary and secondary pedicles, from the circumflex scapular artery, entered the muscle 4.1 cm and 0.5 cm from the scapula, respectively. The lower subscapular nerve entered 4.1 cm from the scapula. Mean tendon and muscle lengths were 2.0 and 11.8 cm, respectively. As a unipolar transfer, the tendon reached the greater tuberosity in all but 1 specimen. The bipolar transfer offered numerous theoretical possibilities. We believe that the teres major has an appropriate vascular supply and adequate length to make it suitable for tendon transfer to the humeral head.

Geographic variations in the rates of operative procedures involving the shoulder, including total shoulder replacement, humeral head replacement, and rotator cuff repair.

BACKGROUND: Although geographic variations in the rates of orthopaedic procedures have been well documented, considerable controversy remains regarding the factors that drive these variations, particularly the role of the availability of orthopaedic surgeons. Moreover, little attention has been specifically focused on variations in the rates of commonly performed shoulder procedures. METHODS: The current study documents state-to-state variations in the rates of total shoulder replacement, humeral head replacement, and rotator cuff repair and examines factors that might account for these variations. The regional incidences of these three procedures were analyzed with use of the Health Care Financing Administration Medicare database (MEDPAR, 1992). The rates were age-adjusted, and variations were measured with use of high:low ratios, variation coefficients, and systematic components of variation. Potential causes of variation were analyzed with use of Spearman and partial correlations as well as with Poisson regression. RESULTS: Rates for the three procedures that were studied varied from one state to another by as much as tenfold. Humeral head replacement had the lowest rate of variation according to all three measures. All three procedures were performed less often in states that were more densely populated. With the numbers available for study, no consistent, significant relationship was found between the density of orthopaedists and shoulder surgeons and the rates of any procedure. CONCLUSIONS: The striking variations that were noted for these commonly performed procedures showed that there is a clear need for well designed clinical research to further define the factors that account for the variations and to examine the effectiveness and appropriate indications for the procedures.