Subscapularis function after transosseous repair in shoulder arthroplasty: transosseous subscapularis repair in shoulder arthroplasty.

BACKGROUND: Postoperative subscapularis function has been identified as an essential factor influencing the outcome of shoulder arthroplasty. The goal of this study was an evaluation of subjective and objective subscapularis function after transosseous refixation. METHODS: Twenty-three patients with an average age of 71 years (range, 51-86) and follow-up of 43 months (range, 24-67) were included in this study. The subscapularis was tenotomized from the lesser tuberosity and refixation was performed in a transosseous technique through bone tunnels with nonabsorbable sutures. Subscapularis function was evaluated subjectively by the ability to tuck a shirt and objectively with the lift-off test and strength measurement in internal rotation. Radiological assessment included ultrasound evaluation of the subscapularis and an axillary x-ray. RESULTS: No complete, but 7 partial subscapularis tears were found on ultrasound (30.4%). Five patients were not able to tuck their shirt postoperatively (22.7%). This was associated with an inferior clinical outcome (American Shoulder and Elbow Surgeons [ASES] score 53.3 vs 76.4; P = .023). The lift-off test was positive in 4 patients  (17.4%), which was also associated with an inferior clinical result (Constant score 52.3% vs 74.2%; P = .021). Nineteen patients were able to go through an internal rotation strength testing in the lift-off position, and averaged 3.8 kg. CONCLUSION: Although overall reliable refixation of the subscapularis was achieved by transosseous repair, almost 25% of patients showed signs of decreased function and 30% showed signs of partial defects. Subjective and objective functional deficits had a significant influence on the clinical outcome.

Effect of posterior offset humeral components on range of motion in reverse shoulder arthroplasty.

The purpose of this study was to evaluate the effect of eccentric humeral components with different degrees of posterior offset on range of glenohumeral motion in reverse shoulder arthroplasty. Uncemented PROMOS® reverse shoulder prostheses were implanted in eight human cadaveric shoulder specimens. Passive range of motion was evaluated with a robot-assisted shoulder simulator. Three movements were tested: abduction, anterior elevation and external rotation. Each specimen was tested with a customary reverse humeral component and two eccentric components with 3 and 6 mm of posterior offset respectively. Mean abduction was 81° (standard deviation [SD] 12) for the customary reverse components, 81° (SD 13) for the 3 mm eccentric and 82° (SD 15) for 6-mm eccentric implants. Mean anterior elevation was 68° (SD 13) in the regular group and 66° (SD 14) and 63° (SD 14) for 3- and 6-mm eccentric groups. With all configurations, 90° of external rotation were achieved without requiring more than 2 N·m of applied rotational moment. Although there was no statistically significant difference between the conventional and the eccentric implants, anterior elevation was decreased by almost 20° in three of eight shoulders with the posterior offset configurations. This was due to a conflict between the proximal humerus and the anterior aspect of the acromion or the coracoid. Although eccentric humeral components can be useful in reverse shoulder arthroplasty to avoid anterior cortical defects in individuals with pronounced humeral head posterior offset, a potential conflict between proximal humerus and scapula may have an unfavourable effect on range of anterior elevation. However, this observation is only true for the uncemented PROMOS® reverse prosthesis. Other reverse shoulder designs with posterior offset components are yet to be tested.

The influence of arthroscopic subscapularis tendon and capsule release on internal rotation strength in treatment of frozen shoulder.

BACKGROUND: Arthroscopic release of the capsule is a popular treatment option for chronic refractory frozen shoulder. Additional release of the intra-articular part of the subscapularis is controversial regarding possible impairment of subscapularis function. HYPOTHESIS: Arthroscopic release of the intra-articular part of the subscapularis produces good clinical results and does not lead to reduced internal rotation strength. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty-two patients were retrospectively evaluated 53 months (range, 12-106) after undergoing arthroscopic anterior capsular release, including release of the intra-articular portion of the subscapularis. Clinical outcome was evaluated using the American Shoulder and Elbow Surgeons score and the Constant score. Isometric and isokinetic strength for internal and external rotation were determined at the time of follow-up in both shoulders using a Cybex dynamometer. RESULTS: The Constant score was improved significantly from 17.7 points to 82.8 points (P < .0001) and the American Shoulder and Elbow Surgeons score increased significantly from 23.5 points to 76.8 points (P < .0001). The mean range of motion was significantly improved for external rotation from 16 degrees to 58 degrees , from 66 degrees to 142 degrees for abduction, and from 76 degrees to 155 degrees for forward flexion. Isometric and isokinetic strength in the standard abduction position of the Cybex dynamometer showed no significant side-to-side difference. CONCLUSION: Arthroscopic capsular release combined with a release of the intra-articular portion of the subscapularis tendon revealed good clinical results in the arthroscopic treatment of adhesive capsulitis without significant loss of internal rotation strength.

Acetabular augmentation ring for recurrent dislocations in revision arthroplasty.

UNLABELLED: We retrospectively reviewed 18 patients with recurrent dislocations after revision total hip arthroplasty with no identifiable specific cause. All patients were treated with an acetabular component augmentation ring to evaluate whether the acetabular augmentation ring effectively decreases the redislocation rate compared with other treatment options. The acetabular augmentation ring was implanted after an average of 4.9 dislocations and failed nonoperative or surgical treatment. Seven patients had postoperative complications, including four patients with persistent neurologic deficits. The average followup was 35.1 months (range, 24-52 months). During followup six patients experienced a dislocation. Four patients and three patients presented with implant loosening and deep infection, respectively. Overall, 10 patients had surgical revision and removal of the acetabular augmentation ring during followup. The remaining eight patients, who did not require additional surgical intervention, had an average Harris hip score of 42.5 (range, 9.5-61.7). The use of an acetabular augmentation ring is not supported by results of our study. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series--no, or historical control group). See the Guidelines for Authors for a complete description of levels of evidence.

Influence of postoperative immobilization on tendon length after radiofrequency-induced shrinkage. An in vivo rabbit study.

BACKGROUND: Despite the widespread use of radiofrequency-induced shrinkage of collagenous tissues, there have been no animal studies on the effects of postoperative immobilization after such treatment. PURPOSE: To examine the effects of postoperative immobilization after radiofrequency energy treatment, with special emphasis on any tissue length increases. STUDY DESIGN: Controlled laboratory study. METHODS: The right patellar tendon of 60 New Zealand White rabbits was shrunk with a radiofrequency probe. Tendon length was measured intraoperatively before and after shrinkage and via radiographs immediately postoperatively and at 3, 6, and 9 weeks. Twenty rabbits were not immobilized, 20 were immobilized for 3 weeks, and 20 were immobilized for 6 weeks. RESULTS: In the nonimmobilized limbs, the tendon length increased 34.9% at 3 weeks and another 2.5% at 6 weeks, versus 11.2% at 3 weeks and 6.6% at 6 weeks in the immobilized limbs. Ten of the 20 rabbits that were immobilized for 6 weeks were sacrificed at 9 weeks and were found to have a further length increase of 10.8%. At 9 weeks, the tendons of this group were no longer significantly shorter than the tendons from rabbits that had not been immobilized. CONCLUSIONS: Careful postoperative rehabilitation is imperative after radiofrequency-induced shrinkage. Without protection, exposure to normal physiologic loads places the shrunken tissue at risk of stretching out beyond the preshrinkage length. CLINICAL RELEVANCE: Shrunken tissue is at risk of stretching out after radiofrequency-induced shrinkage.

Quality of life and back pain: outcome 16.7 years after Harrington instrumentation.

STUDY DESIGN: A study on the quality of life of 82 patients with idiopathic scoliosis treated with Harrington instrumentation. OBJECTIVE: To analyze long-term health-related quality of life and low back pain an average of 16.7 years after surgery. SUMMARY AND BACKGROUND DATA: Quality of life evaluated by self-assessment questionnaires is an accepted outcome measure of surgical procedures. The purpose of this study was to evaluate the health status with the German version of internationally accepted and psychometrically tested questionnaires. METHODS: Quality of life was measured with the Short Form-36 health profile. Low back pain was assessed using the Roland-Morris Questionnaire. Demographic data (age, sex, follow-up time), radiographic analysis (Kings classification, Cobb angle, extension and site of fusion), and rib cage deformity were correlated with these data. Radiologic parameters were analyzed longitudinally. RESULTS: In comparison with the age-matched healthy population, there was no significant difference in the physical Short Form-36 scale (P = 0.98). Surgically treated patients showed significantly lower scores than at baseline in the psychologic Short Form-36 scale (P = 0.005); vitality (P < 0.001), general mental health (P = 0.003), and role activities because of emotional problems (P < 0.001) were significantly different from those of the age-matched population. Sixty-five (79.3%) of the 82 patients reported no or occasional back pain in the Roland-Morris Questionnaire. Five patients (6.1%) reported chronic back pain. Neither patient age at the time of surgery (P = 0.74) nor time of follow-up (P = 0.44), type of scoliosis (P = 0.56), or extent of fusion (P = 0.12) was associated with health-related quality of life or pain. The size of the preoperative (P = 0.06) and postoperative (P = 0.12) curves and preoperative (P = 0.28) and postoperative (P = 0.7) rib cage deformities did not correlate with the data of the Short Form-36 scale and the Roland-Morris Questionnaire. CONCLUSIONS: In comparison with the age-matched population, the long-term effect of surgery does not affect the physical quality of life. The psychologic health status is, however, significantly impaired. Neither the type of curve, the size of scoliosis, nor the rib cage deformity influences the data.