ABSTRACT
OBJECTIVE: To evaluate the humeral head bone volume of patients with cuff tear arthropathy (CTA) and examine the therapeutic effect of zoledronate in a rat modified model of CTA (mCTA). DESIGN: The bone mass in patients with CTA was measured using Hounsfield units from CT images. The mCTA was induced by transecting the rotator cuff, biceps brachii tendon, and superior half of the joint capsule in adult rat shoulders. A single subcutaneous injection of zoledronate was followed by bone histomorphometry and immunohistochemistry of the humeral head, as well as the Murine Shoulder Arthritis Score (MSAS) assessment. RESULTS: The humeral head bone volume was decreased in patients with CTA. In the mCTA model, M1 macrophages were increased in the synovium and were decreased by zoledronate treatment. The increased expressions of TNF-α, IL-1ß and IL-6 in mCTA synovium and articular cartilage were suppressed in the zoledronate-treated mCTA group. The expression of catabolic enzymes in the articular cartilage and MSAS showed similar results. The zoledronate-treated mCTA group showed a decreased subchondral bone collapse with a decreased RANKL/OPG expression ratio and a suppressed number of osteoclasts compared with the control mCTA group. The enhanced expressions of HMGB1 and S100A9 in the mCTA shoulders were eliminated in the zoledronate-treated mCTA group. CONCLUSIONS: The humeral head subchondral bone was decreased in patients with CTA. In the mCTA model, the collapse and osteoarthritic changes were prevented by zoledronate administration. Zoledronate seemed to suppress the number of M1 macrophages in the synovium and osteoclasts in the subchondral bone.
ABSTRACT
PURPOSE: One of the major problems in revision total hip arthroplasty (THA) is severe acetabular bone loss. The aim of our study was to evaluate the clinical outcomes of revision THA using a Kerboull-type reinforcement device (KT plate) and allogeneic structural bone graft. METHODS: This retrospective study evaluated 48 hips that underwent revision THA using a KT plate and allogeneic structural bone graft between 2008 and 2016, with a median follow-up of 6.2 years (range 3-12.6 years). Functional outcome was assessed using the Japanese Orthopaedic Association (JOA) hip score. Postoperative and follow-up radiographs were compared to assess migration and breakage of the implant. RESULTS: The mean JOA hip score improved from 45.6 (±16.3) points before surgery to 72.1 (±11.9) points at the most recent follow-up examination (p < 0.001). Two hips (4.2%) underwent re-revision THA because of cup loosening due to breakage of the KT plate. A total of 13 hips (27.1%) were classified as radiological failures. Binomial logistic regression analysis showed that a Kawanabe classification of stage 4, which indicates massive bone defects in the weight-bearing area, was a risk factor for radiological failure (odds ratio: 4.57; 95% confidence interval: 1.01-26.35). CONCLUSIONS: A KT plate with an allogeneic structural bone graft is a useful method of acetabular reconstruction in revision THA that restores bone stock and improves hip function. Our findings indicated that a Kawanabe classification of stage 4 was a risk factor for radiological failure of the implant.