Patients with acetabular dysplasia commonly undergo peri-acetabular osteotomy after skeletal maturity to reduce the risk of the late development of osteoarthritis. Several studies have suggested that deformity of the femoral head influences the long-term outcome. We radiologically examined 224 hips in 112 patients with acetabular dysplasia and early-stage osteoarthritis. There were 103 women and nine men with a mean age of 37.6 years (18 to 49). A total of 201 hips were placed in the acetabular dysplasia group and 23 in a normal group. The centre–edge angle and acetabular head index were significantly smaller (both p < 0.001), and the acetabular angle, acetabular roof angle and roundness index were significantly greater in the acetabular dysplasia group than those in the normal group (all p < 0.001). There were significant correlations between the roundness index and other parameters. Femoral head shape may be influenced by the severity of the acetabular dysplasia.

Cite this article: Bone Joint J 2013;95-B:1192–6.

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.

We investigated the effect of the Birmingham hip resurfacing (BHR) arthroplasty on the bone mineral density (BMD) of the femur. A comparative study was carried out on 26 hips in 25 patients. Group A consisted of 13 patients (13 hips) who had undergone resurfacing hip arthroplasty with the BHR system and group B of 12 patients (13 hips) who had had cementless total hip arthroplasty with a proximal circumferential plasma-spray titanium-coated anatomic Ti6A14V stem. Patients were matched for gender, state of disease and age at the time of surgery. The periprosthetic BMD of the femur was measured using dual-energy x-ray absorptiomentry of the Gruen zones at two years in patients in groups A and B.

The median values of the BMD in zones 1 and 7 were 99% and 111%, respectively. The post-operative loss of the BMD in the proximal femur was significantly greater in group B than in group A. These findings show that the BHR system preserves the bone stock of the proximal femur after surgery.

Introduction: Little comparative information is available regarding asymptomatic and symptomatic rotator cuff tears. This data may lend insight to Natural History. The purpose of this study was to compare the morphology and incidence of cuff disease in people with unilateral painful shoulders.

Methods: 588 consecutive shoulder ultrasounds were reviewed in patients presenting with unilateral pain. Ultrasound has been validated in our institution as highly accurate. There were 212 pt/bilat intact cuffs, 191pt/unilateral tears, and 185pt/bilateral tears. Data for age, cuff thickness, tear size, and symptoms were tested for associations.

Results: Cuff disease increased with average age, (no tear/48.7yo,unilateral tear/58.7yo,bilateral tears/67.8yo). Logistic regression showed a 50% likelihood of bilateral tears after age 66(p< .01). Overall, a pt. with a full tear on the symptomatic side had a 35.5% incidence of an asymptomatic tear. In contrast, a symptomatic nl. or partial tears had only a 0.5% or 4.3% incidence of contralateral tear. In patients with bilateral tears, the symptomatic side was larger (p< .01). 65% of painful tears were on the dominant side(p< .01). For intact cuffs, avg thickness equaled 4.7 mm and was not affected by age, gender, or symptoms.

SUMMARY: The high incidence of asymptomatic and bilateral tears with age suggests that for some, cuff disease is intrinsic; however, the association with symptoms of hand dominance and increased tear size indicate that extrinsic factors may be important in the development of pain.