Healing of the subscapularis, documented by ultrasound, following total shoulder arthroplasty was examined in thirty shoulders. All had marked improvement in pain, SST, and ASES scores. Four subscapularis tears were identified but only one patient had a positive abdominal compression test, 7/26 patients had a positive compression test despite an intact cuff, and 4/7 patients had a significant internal rotation contracture. The abdominal compression test was not accurate in detecting sub-scapularis tears. There was a significant false positive rate, which may be related to a lack of internal rotation. Overall, the outcome was excellent and not related to the status of the subscapularis. Very little information is available on healing of the subscapularis after shoulder arthroplasty. The purpose of this study was to document the subscapularis healing rate and relate it to post-operative function and the abdominal compression test. Thirty consecutive shoulders (twenty-three patients) s/p total shoulder replacement had standardized pre- and post-operative examinations including quantitative strength assessment and specific subscapularis testing. Ultrasound (validated for postop accuracy) was performed to document tendon healing. All thirty shoulders had marked improvements in pain, SST, and ASES scores. Four subscapularis tears were identified but only one patient had a positive abdominal compression test. Seven out of twenty-six patients had a positive compression test despite an intact cuff. Four of seven patients had a significant internal rotation contracture. Neither the status of the subscapularis nor a positive compression test appeared to affect outcome. Although specific subscapularis tests are often positive, only a small percentage of subscapularis tendons appear to retear after shoulder arthroplasty. The abdominal compression test is not accurate in detecting subscapularis tears post arthroplasty. There is a significant false positive rate, which may be related to a lack of internal rotation. However, overall outcome of shoulder arthroplasty was excellent and did not appear to be dependant on the status of the subscapularis.
Since the autumn of 2003, a computer-assisted system (VectorVision® Hip, version 2.1, Brain LAB, Germany) has been used to perform total hip arthroplasty (THA) operations in our hospital. In the present study, the postoperative acetabular cup position was evaluated using the records of the system and the data measured from postoperative radiographs. To date, 18 patients have been treated using this-system. We studied the cup inclination and anteversion records in this system recorded in the THA procedures. We also measured the cup inclination and anteversion using postoperative radiographs, according to the method described by Pradhan. The inclination and ante-version were the ‘operative’angles for this system and were the ‘radio graphical’ ones for measuring from the radiographs according to the definition described by Murray. The initial planning of the acetabular cup position was 45° ‘operative’ inclination and 20° ‘operative’ ante-version. From the system records, the average ‘operative’ inclination was 46.5°± 3.9° and the average ‘operative’ anteversion was 25.5°± 6.0°. The average ‘radio graphical’ inclination measured from the postoperative radiographs was 49.0°± 6.0°, and the average ‘radio graphical’ anteversion was 10.6°± 5.8°. Between the ‘operative’ angles from this system and the ‘radio graphical’ angles from the postoperative radiographs, the inclination was approximately the same, while the anteversion was different. When the ‘radio graphical’ anteversion was corrected for X-ray beam spreading and then converted to the ‘operative’ anteversion, the resulting ‘operative’ anteversion was 21.1°± 7.8°. And when the ‘operative’ anteversion recorded by this system was corrected for the pelvic tilt, the corrected ‘operative’ anteversion was 22.1°± 6.5°. The average difference between these corrected ‘operative’ anteversion in each case was 5.8°± 3.8°. Especially in 10 of the 18 cases, each difference was within 5°. The accuracy of the cup position using this computer-assisted system was shown by this study.