Abstract
Background
Modular component options can assist the surgeon in addressing complex femoral reconstructions in total hip arthroplasty (THA) by allowing for customization of version control and proximal to distal sizing. Tapered stem fixation has a proven excellent track record in revision THA. Early reports by Cherubino et al. (Surg Technol Int 2010) 65 revision THA with an average follow up of 109 months (range, 76–131) demonstrate satisfactory integration in 100% of cases. Rodriguez et al.(J Arthroplasty 2009) report 96% survival in 102 revision THA at nearly 4 years average follow up. We review the early clinical results of a modular tapered femoral revision system.
Methods
A query of our practice's arthroplasty registry revealed 60 patients (61 hips) who signed an IRB-approved general research consent allowing retrospective review, and underwent THA performed with the modular femoral revision system between December 2009 and April 2012. There were 35 men (58%) and 25 women (42%). Mean age was 65.1 years (range, 35–94) and BMI was 31.3 kg/m2 (range, 14–53). Procedures were complex primary in 1 hip, conversion in 6 (10%), revision in 32 (53%), and two-staged exchange for infection in 22 (33%). Two-thirds of the procedures included complete acetabular revision (n=40), while 31% (19) involved liner change only and 2 were isolated femoral revisions.
Results
At an average follow-up of 1.5 years (maximum: 3.7 years) there have been no revisions or failures of the femoral component. Average Harris hip scores (0 to 100 possible) improved from 44.2 preoperatively to 66.0 at most recent evaluation, while the pain component (0 to 44 possible) improved from 15.8 to 31.2. Complications requiring surgical intervention included intraoperative periprosthetic femur fracture in one patient returned to the operating suite same day for open reduction internal fixation, which further required incision and debridement for superficial infection at 1 year postoperative; and two patients with dislocation and fracture of the greater trochanter treated with open reduction, revision of the head and liner, and application of cerclage cables, one of which required removal of a migrated claw 10 months later followed 2 weeks subsequently with incision and debridement for a non-healing wound. Postoperative radiographs were available for review for 59 THA in 58 patients. Analysis of the femoral component revealed satisfactory findings in 50 hips (85%) while 9 had radiographic changes that included bone deficit, osteolysis, or radiolucency in one or more zones.
Conclusions
The early results of this modular femoral revision system are promising for the treatment of the deficient femur in complex primary and revision total hip arthroplasty. Patients with radiographic changes are advised to return for regular clinical and radiographic follow-up. Survival of the modular femoral component in this series was 100% at mean follow-up of 1.5 years and up to 3.7 years. While Harris hip clinical and pain scores were somewhat low at most recent evaluation, they were significantly improved over preoperative levels.
