Highly Cross-Linked Polyethylene in Cementless Total Hip Arthroplasty in Patients with Previous Acetabular Fractures: A Minimum 5-Year Follow-Up Study.

BACKGROUND

Outcomes of THA after acetabular fracture are generally less favorable than those of the nontraumatic arthritis due to a higher rate of cup loosening and osteolysis. We, therefore, investigated whether highly cross-linked polyethylene liners positively impact outcomes of THA in patients with posttraumatic osteoarthritis after acetabular fracture.

METHODS

We retrospectively evaluated 39 patients with previous acetabular fracture who underwent THA using highly cross-linked polyethylene liner after a mean 8.5 year follow-up. All procedures were performed at a single institution by a single surgeon using the same type of THA implants. Wear measurements were performed using a computer-assisted PolyWare software. Osteolysis was evaluated with use of radiography and computed tomography.

RESULTS

The mean preoperative Harris hip score was 44.4 points, which improved to 93.1 points at final follow-up. Neither femoral nor acetabular components displayed mechanical loosening and no components had been revised. Radiographs and CT scans did not demonstrate osteolysis. The mean linear wear was 0.043 mm/y (range 0-0.098 mm/y). With the data available, univariate regression analysis suggests that age, gender, weight, initial fracture type, the duration of follow-up, activity level, liner thickness, acetabular cup inclination, and the necessity of bone graft had no influence on liner penetration.

CONCLUSION

While the long-term effects of the polyethylene particles from highly cross-linked polyethylene remain unknown, implant survivorship and wear data in this study are promising for this high-risk population. Our encouraging results support the continued use of this type of polyethylene in patients after acetabular fractures.

LEVEL OF EVIDENCE

Level IV Therapeutic study.