Peter Habermeyer

Magnetic resonance imaging of arthroscopic supraspinatus tendon repair.

BACKGROUND While a number of studies have documented the very good clinical results of arthroscopic rotator cuff repair, very few authors have specifically assessed cuff integrity, supraspinatus atrophy, and fatty infiltration and their influence on the clinical outcome. METHODS We evaluated fifty-three consecutive patients (average age, 60.9 years) who had undergone arthroscopic repair of an isolated supraspinatus tendon tear. After an average duration of follow-up of 26.4 months, all patients were evaluated clinically with use of the Constant score and underwent standardized magnetic resonance imaging at our institution. The preoperative and postoperative magnetic resonance images were evaluated by two independent observers who were blinded to the clinical outcome of the patient. Evaluation criteria were cuff integrity; atrophy of the supraspinatus; and fatty infiltration of the supraspinatus, infraspinatus, and subscapularis. These findings were correlated to the clinical outcome. RESULTS Regardless of the tendon integrity, every parameter of the Constant score was significantly improved after the repair. The overall average Constant score was improved from 53.5 to 83.4 points (p < 0.001). The retear rate in our series was 25% (thirteen of fifty-three). Patients who had a retear had significantly less abduction strength (p = 0.043) and a significantly lower total Constant score (p = 0.012) than those who had an intact repair. A higher degree of preoperative supraspinatus atrophy and Stage-2 fatty infiltration of the supraspinatus were positive predictors of a retear. Also, an older age was an important predictor of a retear (p = 0.011). Progression of structural changes in the rotator cuff was halted when the repair remained intact, but there was no significant reversal of fatty infiltration or muscle atrophy. When the repairs failed, there was significant progression of fatty infiltration and atrophy of the supraspinatus. CONCLUSIONS The clinical and structural results of arthroscopic repairs of isolated supraspinatus tears are equal to those reported following open repair. Fatty infiltration and muscle atrophy cannot be reversed by successful arthroscopic repair. Higher degrees of muscular atrophy and fatty infiltration preoperatively are associated with recurrence of the tear as well as progression of fatty infiltration and muscular atrophy and an inferior clinical result.

Postoperative Subscapularis Muscle Insufficiency After Primary and Revision Open Shoulder Stabilization

Background Postoperative subscapularis muscle insufficiency after open shoulder stabilization procedures represents an unrecognized condition. Hypothesis Primary and revision open shoulder stabilization using the inverted L-shaped tenotomy approach impairs subscapularis muscle recovery and affects final clinical outcome. Study Design Cohort study; Level of evidence, 3. Methods Twenty-five patients who underwent primary (group 1: n = 13; mean age, 36.5 years; follow-up, 48 months) or revision (group 2: n = 12; mean age, 34.2 years; follow-up, 52 months) open shoulder stabilization procedures were followed up clinically (clinical subscapularis tests and signs, Constant score, and Rowe score) and by magnetic resonance imaging (tendon integrity, defined muscle diameters, and signal intensity analysis [ratio infraspinatus/upper subscapularis muscle and infraspinatus/lower subscapularis muscle]). A third group (group 0) of 12 healthy volunteers served as a control. Results Clinical signs for subscapularis muscle insufficiency were present in 53.8% of cases in group 1 and 91.6% of cases in group 2. There were no significant differences between groups with regard to Constant and Rowe scores (P >. 05). On magnetic resonance imaging, no complete tendon ruptures were found. The mean vertical diameter of the subscapularis muscle and the mean transverse diameter of the upper subscapularis muscle portion were significantly greater in group 0 than in group 1 and greater in group 1 than in group 2 (P <. 05). The mean transverse diameter of the lower subscapularis muscle was comparable in all groups (P >. 05). The signal intensity analysis revealed the infraspinatus/upper subscapularis muscle ratio was greater in group 0 than in group 1 and greater in group 1 than in group 2 (P <. 05). The infraspinatus/lower subscapularis muscle ratio was lower in group 0 than in groups 1 and 2 (P <. 05). Conclusion Open shoulder stabilization using an inverted L-shaped tenotomy approach may lead to atrophy and fatty infiltration, particularly of the upper part of the subscapularis muscle, resulting in postoperative subscapularis muscle insufficiency. Revision procedures using the same approach may further compromise clinical subscapularis muscle function and structure. The lower portion of the subscapularis muscle seems to have a compensating effect that may, in addition to a meticulous capsulolabral reconstruction, account for the uncompromised overall clinical outcome.

Transfer of the tendon of latissimus dorsi for the treatment of massive tears of the rotator cuff: A NEW SINGLE-INCISION TECHNIQUE

We describe 14 patients who underwent transfer of latissimus dorsi using a new technique through a single-incision. Their mean age was 61 years (47 to 76) and the mean follow-up was 32 months (19 to 42). The mean Constant score improved from 46.5 to 74.6 points. The mean active flexion increased from 119 degrees to 170 degrees , mean abduction from 118 degrees to 169 degrees and mean external rotation from 19 degrees to 33 degrees . The Hornblower sign remained positive in three patients (23%) as did the external rotation lag sign also in three patients (23%). No patient had a positive drop-arm sign at follow-up. No significant difference was noted between the mean pre- and postoperative acromiohumeral distance as seen on radiographs. An increased grade of osteoarthritis was found in three patients (23%). Electromyographic analysis showed activity of the transferred muscle in all patients.

Osteochondral autologous transplantation for the treatment of full-thickness articular cartilage defects of the shoulder

We describe the outcome at a mean follow-up of 8.75 years (7.6 to 9.8) of seven patients who had undergone osteochondral autologous transplantation for full-thickness cartilage defects of the shoulder between 1998 and 2000. These patients have been described previously at a mean of 32.6 months when eight were included. One patient has been lost to follow-up. The outcome was assessed by the Constant shoulder score and the Lysholm knee score to assess any donor-site morbidity. Standard radiographs and MR scores were obtained and compared with the pre-operative findings and the results from the previous review. No patient required any further surgery on the shoulder. The mean Constant score improved significantly until the final follow-up (p = 0.018). The Lysholm score remained excellent throughout. There was a significant progression of osteoarthritic changes from the initial surgery to the first and final follow-up but this did not appear to be related to the size of the defect, the number of cylinders required or the Constant score (p = 0.016). MRI showed that all except one patient had a congruent joint surface at the defect with full bony integration of all osteochondral cylinders. The results have remained satisfactory over a longer period with very good objective and subjective findings.

Three-Dimensional Glenoid Deformity in Patients with Osteoarthritis: A Radiographic Analysis

BACKGROUND In osteoarthritis of the shoulder, the tilt of the glenoid surface undergoes an eccentric deformation not only in the anteroposterior but also in the superoinferior direction. The goals of this study were to analyze glenoid version in the coronal plane and to clarify the relationship between retroversion and inferior inclination of the glenoid. METHODS Standardized radiographs of 100 consecutive patients with primary osteoarthritis of the shoulder and 100 otherwise healthy patients with shoulder pain (the control group) were included in this study and were analyzed by two independent observers. RESULTS We defined four different types of inclination deformity of the glenoid. In a type-0 glenoid, a line at the base of the coracoid process and a line at the glenoid rim run parallel. Both lines intersect below the inferior glenoid rim in a type-1 glenoid. In a type-2 glenoid, the line at the base of the coracoid process and the glenoid line intersect between the inferior glenoid rim and the center of the glenoid. In a type-3 glenoid, the lines intersect above the base of the coracoid process. A significant difference (p < 0.0001) in the distribution of glenoid types between the two patient groups was observed. Forty-seven patients with osteoarthritis showed combined posterior and inferior glenoid wear. We found no correlation between the type of inclination and the type of glenoid morphology. The interobserver reliability of our observations was very high. CONCLUSIONS In osteoarthritis, eccentric inferior glenoid wear is frequent and independent from retroversion deformity of the glenoid. Normalization of glenoid version in both transverse and coronal planes may reduce eccentric loading of the prosthetic glenoid, which has been associated with loosening.

Improved accuracy of glenoid positioning in total shoulder arthroplasty with intraoperative navigation: A prospective-randomized clinical study

HYPOTHESIS The correct implantation of the glenoid component is of paramount importance in total shoulder arthroplasty (TSA). We hypothesized that the accuracy of the glenoid positioning in the transverse plane can be improved using intraoperative navigation. MATERIALS AND METHODS This prospective, randomized clinical study comprised 2 groups of 10 patients each with osteoarthritis of the shoulder TSA, with or without intraoperative navigation. Glenoid version was measured on axial computed tomography scans preoperatively and 6 weeks postoperatively. RESULTS The operating time was significantly longer in the navigation group (169.5 +/- 15.2 vs 138 +/- 18.4 min). We found an average change of retroversion from 15.4 degrees +/- 5.8 degrees (range, 3.0 degrees -24.0 degrees) preoperatively to 3.7 degrees +/- 6.3 degrees (range, -8.0 degrees to 15.0 degrees) postoperatively in the navigation group compared with 14.4 degrees +/- 6.1 degrees (range, 2.0 degrees -24.0 degrees) preoperatively to 10.9 degrees +/- 6.8 degrees (range, 0.0 degrees -19.0 degrees) postoperatively in the group without navigation (P = .021). CONCLUSION We found an improved accuracy in glenoid positioning in the transverse plane using intraoperative navigation. The validity of the study is limited by the small number, which advocates continuation with more patients and longer follow-up. LEVEL OF EVIDENCE Level 2; Therapeutic study.

Open reconstruction of anterior glenoid rim fractures

The present study evaluates the clinical and radiological results of patients with anterior glenoid rim fractures treated with two different open surgical techniques depending on the size of the bony fragment. In patients with displaced glenoid rim fractures involving less than 25% of the glenoid surface (Type I, II and IIIA fractures) suture anchor repair was performed. Patients with a bony defect involving more than 25% of the glenoid surface (Type IIIB fractures) underwent open reduction and internal fixation using cannulated screws. After a mean follow-up of 22 months, 15 patients (mean age 42.2 years) treated with suture anchor repair achieved an average Constant Score of 85.5 points (range 67.1–100) and an average Rowe Score of 94 points (range 70–100). In six patients the bony fragment was located in an unimproved medial position compared to the preoperative X-ray. In another six patients the fragment was consolidated medially to the level of the glenoid rim, and in three cases an anatomic situation was found. Patients treated with cannulated screws (ten cases, mean age 46.6 years) had a mean follow-up of 30 months and achieved a mean Constant Score of 81.9 points (range 61.7–96.1) and a mean Rowe Score of 90 points (range 70–100). Radiologically, the bony fragment was consolidated in an anatomic position in nine out of ten cases. Three patients suffered from screw impingement and one patient had screw loosening. No recurrent subluxations or dislocations were observed in either group. Three patients in group one and one patient in group two had glenohumeral osteoarthritic changes. In cases of small glenoid-rim fractures (Type I, II and IIIA fractures), suture anchor repair resulted in an excellent clinical outcome; however, the radiological results of chronic Type I fractures revealed in many cases a non-anatomical glenoidal reconstruction. For Type IIIB fractures with significant loss of glenoid concavity, open reduction and internal fixation with cannulated screws gave good clinical and radiological results; however the early complication rate was higher.

Recentering the humeral head for glenoid deficiency in total shoulder arthroplasty.

Substantial posterior glenoid wear causing static posterior subluxation of the humeral head in patients with primary osteoarthritis has been described. Persistent humeral head subluxation after total shoulder arthroplasty can result in early polyethylene wear and glenoid component loosening. In our prospective cohort study, we hypothesized that in patients with posterior glenoid wear from osteoarthritis, static posterior decentering of the humeral head could be recentered during total shoulder arthroplasty by surgical correction of glenoid alignment in the transverse plane with soft tissue balancing. We performed total shoulder arthroplasties in 77 patients with primary osteoarthritis and a mean age of 67.6 years. The mean clinical and radiographic followup was 2 years (range, 1-7 years). Patients with preoperative posteriorly decentered humeral heads did not have posterior decentering develop postoperatively. Twenty patients (83.3%) had centered humeral heads and four patients (16.6%) had anterior decentering. Midterm results of total shoulder arthroplasties in shoulders with humeral head decentering caused by glenoid deficiency in the transverse plane showed correction of the decentering by lowering the high side or by bone grafting with soft tissue balancing can be well maintained.Level of Evidence: Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

A new arthroscopic classification of articular-sided supraspinatus footprint lesions: a prospective comparison with Snyder's and Ellman's classification.

The aim of this study was to find a descriptive rationale to quantify articular-sided supraspinatus tendon tears in the transverse and coronal planes, leading to a 2-dimensional description of the tear pattern. Fifty-six consecutive patients with articular-sided, symptomatic supraspinatus tendon tears diagnosed clinically and by magnetic resonance imaging underwent standardized diagnostic arthroscopy. Intra-articular findings of the rotator cuff were classified according to Ellman and Snyder. In addition, the longitudinal tear was assessed according to the length of the peeled-off bony footprint in the coronal plane. The sagittal tear extension was defined as a tear of the lateral reflection pulley on the medial border of the supraspinatus tendon and/or a tear in the area of the crescent zone. Statistically, we found a high correlation (r = 0.920, P < .0001) between the classifications of Ellman and Snyder, and we found only a slight correlation between the classifications of Snyder and Ellman with this new classification. Neither the classification of Snyder nor that of Ellman reproduced the extension of the partial-thickness rotator cuff tear in the transverse and coronal planes related to its etiologic pathomorphology.

Subscapularis dysfunction following anterior surgical approaches to the shoulder

Subscapularis dysfunction following open surgical exposure of the glenohumeral joint has recently received attention. Clinical studies, in particular those that have investigated the results after open shoulder stabilization or shoulder replacement surgery, indicate that anterior approaches using different subscapularis tendon take-down or incision techniques may impair subscapularis recovery and can negatively influence the final clinical outcome. This review article will focus on the potential pathogenesis, diagnosis, and clinical impact of this more and more recognized condition and summarizes the currently available literature.