Incidence of complications and revision surgery in HAART compliant HIV patients undergoing primary total hip and knee arthroplasty: an institutional review.

INTRODUCTION: Human immunodeficiency virus (HIV) positive patients are at high risk for osteonecrosis along with age-related osteoarthritis, resulting in a high number of joint reconstruction surgeries at younger ages in these immunosuppressed patients. Few previous studies have reported on patient outcomes in HAART (highly active antiretroviral therapy) compliant patients undergoing primary arthroplasty. The aim of this study is to report one institution's overall rate of complications and revision in HAART-compliant patients after primary hip and knee arthroplasty. METHODS: A retrospective chart review was performed spanning a 4 year period. This study included 50 primary joint arthroplasty patients diagnosed with HIV including 13 TKA (total knee arthroplasty) and 37 THA (total hip arthroplasty) with a prior diagnosis of HIV infection. Preoperative CD4 count and viral loads were recorded. Charts were reviewed for post-operative complications including infection and revision. RESULTS: The were a total of 11 postoperative complications (22%). There were 3 cases (6%) of soft tissue infection, 3 cases (6%) of implant loosening, 2 cases (4%) of dislocation, 1 case (2%) of lower extremity weakness, 1 case (2%) of venous thrombosis, and 1 case (2%) of arthrofibrosis. Of all patients, there were 6 cases of revision in this cohort (12%), 5 of which were aseptic etiology. All 3 infected patients had a history of IVDU. Two of these infected patients resolved with IV antibiotics while 1 underwent two-stage revision (2%). Patients that experienced post-operative complications had significantly elevated preoperative CD4 levels (983 versus 598, p = 0.003). CONCLUSION: Arthroplasty is a viable option for HAART-compliant patients. Most previous studies showing a higher risk for deep tissue infection and revision in HIV patients have not accounted for modern HAART. Our results show that compliance with HAART has vastly improved the outcomes of arthroplasty in these patients, while a history of IVDU is likely the largest risk factor for infection in this population.

Bone remodeling and cortical thinning distal to the femoral stem: a retrospective review.

INTRODUCTION: There is a paucity of information on the bone remodeling that occurs distal to the femoral stem following total hip arthroplasty as most previous studies have focused on proximal changes. In this study, we report the cortical thinning that occur distal to the femoral stem after primary total hip arthroplasty. METHODS: A retrospective review was performed at one institution over a 5-year period. 156 primary total hip arthroplasty procedures were included. The Cortical Thickness Index (CTI) was measured on both operative and non-operative hips at 1 cm, 3 cm and 5 cm below the prosthetic stem tip on anteroposterior radiographic images pre-operatively as well as at 6 months, 12 months and 24 months post-operatively. The difference in average CTI was measured using paired t-tests. RESULTS: There were statistically significant decreases in CTI distal to the femoral stem at 12 months and 24 months (-1.3% and -2.8%, respectively). Greater losses were seen in female patients, patients older than 75, and patients with BMI less than 35 at 6 months postoperative. There were no differences in CTI at any time point on the non-operative side. CONCLUSION: The current study demonstrates that patients undergo bone loss as measured by CTI distal to the stem in the first 2 years following total hip arthroplasty. Comparison to the contralateral non-operative side confirms that this change is greater than expected for the natural aging process. A greater understanding of these changes will help optimize post-operative management and direct future innovations in implant design.