Incidence of radiographic cam-type impingement in young patients (<50) after femoral neck fracture treated with reduction and internal fixation.

BACKGROUND: Cam-type femoral impingement is caused by structural abnormalities of the hip and is recognized as a cause of degenerative hip arthritis. Identifiable etiologies of this structural abnormality include congenital malformation, pediatric hip disease, and malunion of femoral neck fractures after internal fixation. PURPOSE: The purpose of this study was to determine the prevalence of radiographic impingement in healed Orthopaedic Trauma Association (OTA) type 31B fractures treated with reduction and internal fixation. METHODS: Seventy OTA 31B hip fractures treated with internal fixation were identified from our institutional trauma database and radiographs were retrospectively reviewed for signs of impingement. Mean follow-up was 53 months after fracture. Alpha angle, Mose templates, and femoral head retroversion were the measurements used to determine impingement. RESULTS: The overall prevalence of any sign of radiographic impingement was 75%. Alpha angle was elevated in 32 hips (46%), asphericity was present in 46 femoral heads (65%), and femoral head retroversion was present in 26 hips (37%). The rates were highest in displaced subcapital fractures (OTA 31B-3) with a 63% (13/19) prevalence of elevated alpha angle, 68% (14/19) prevalence of asphericity, and 47% (10/19) prevalence of retroversion. CONCLUSIONS: Prevalence of radiographic signs of impingement in this population is higher than expected based on population-based controls. Surgeons must be vigilant about reduction and fixation of femoral neck fractures. Malunion should be recognized as early intervention may be beneficial in improving long-term outcomes.

Hybrid total knee arthroplasty analysis of component failures at an average of 15 years.

Hybrid total knee arthroplasty in which the femoral component is cementless and the tibial component is cemented remains controversial. We report on the long-term results of 65 total knee arthroplasties followed for an average of 15 years. There were 18 revisions (27%); of these, 11 were femoral component revisions. The overall implant survival with revision as the end point was estimated as 64% at 15 years. The femoral component survivorship at 15 years was 72%. Because of the high failure rate, hybrid fixation on the femoral side with this design has been abandoned at our institution; but hybrid fixation with a trabecular metal tibia is currently under investigation.

Cemented total knee arthroplasty using a modern prosthesis in young patients with osteoarthritis.

Fifty-two consecutive cemented total knee arthroplasties were performed using the Press-Fit Condylar (DePuy, Warsaw, Ind) knee system on patients aged 55 years or younger at Mayo Clinic Rochester from 1988 to 1994. Patients were followed for a minimum of 10 years, with an average follow-up of 12 years (range, 10-15 years). There were 8 total revisions (15%), including 2 revisions before 10 years, one for sepsis at 1 year, and one for instability at 8 years. Six revisions occurred between 10 and 15 years, all associated with polyethylene wear and osteolysis. Implant survival rate was estimated to be 96% at 10 years and 85% at 15 years of follow-up.