Faculty Bibliography

The primary diagnosis of femoroacetabular impingement is based on clinical symptoms, physical exam findings, and radiographic abnormalities. The study objective was to determine the radiographic findings that correlate with and are predictive of hip pain in femoroacetabular impingement (FAI). One hundred prospective patients with unilateral FAI symptoms based on clinical and radiographic findings were included in this study. All patients filled out a WOMAC pain questionnaire. Two independent-blinded surgeons assessed antero-posterior and lateral radiographs for 33 radiographic parameters of FAI. Correlations between pain scores and radiographic findings were calculated. A matched radiographic analysis was performed comparing symptomatic versus asymptomatic hips. Radiograph findings were also compared between males and females. Weak positive correlations were identified between increasing pain scores with radiographic findings of posterior wall dysplasia, presence of a shallow socket, and a more lateral acetabular fossa relative to the Ilioischial line. A symptomatic hip had a lower neck shaft angle, greater distance from Ilioischial line to acetabular fossa and larger distance from cross-over sign to superolateral point of the acetabulum when compared to the asymptomatic hip in the same patient. Symptomatic hips in males had more joint space narrowing, femoral osteophytes, higher alpha angles and larger, more incongruent femoral heads compared to females. Females had more medial acetabular fossa relative to the Ilioischial line and smaller femoral head extrusion index. Similar to other musculoskeletal conditions, radiographic findings of FAI are poor predictors of hip pain.

Data are limited regarding large ceramic femoral heads with highly cross-linked polyethylene. We hypothesized that large ceramic head articulation with highly cross-linked polyethylene is safe with a low wear rate, comparable to metal-on-highly cross-linked polyethylene.The study group comprised 63 patients (72 hips) who had undergone total hip replacement (THR) with ceramic-on-highly cross-linked polyethylene between April 2006 and March 2007 with a minimum 2-year follow-up. Postoperative Western Ontario and Mc-Master Universities Arthritis Index (WOMAC) and Hospital for Special Surgery (HSS) scores were used for clinical assessment. Six-week and 2-year radiographs were analyzed by 2 independent observers using Roman 1.70 software. Twenty-six patients (29 hips) had 32-mm and 37 patients (43 hips) had 36-mm Biolox delta ceramic femoral heads (Ceramtec, Plochingen, Germany). Mean patient age was 60.9 +/- 8.9 years, and mean follow-up was 2.9 +/- 0.5 years. Mean postoperative WOMAC and HSS hip scores were 30.4 and 36.6, respectively. Mean wear at 1 and 2 years postoperatively was 0.06 +/- 0.28 and 0.006 +/- 0.12 mm/yr for all hips, respectively. Mean wear at 1 and 2 years postoperatively for the 32-mm femoral head was 0.063 +/- 0.278 and 0.007 +/- 0.126 mm/yr, respectively, and for the 36-mm femoral head was 0.057 +/- 0.292 and 0.006 +/- 0.118 mm/yr, respectively. No patient had any clinical complications, such as reoperation, infection, fractures, or radiographic evidence of osteolysis or loosening. The early results of THR with large ceramic heads demonstrate high safety and efficacy. Our data with 2-year follow-up show low wear rates, similar to published data for metal-on-highly cross-linked polyethylene.