A five-year clinical and radiographic follow-up of bipolar hip arthroplasty with insertion of a porous-coated anatomic femoral component without cement.

OBJECTIVE

To evaluate the clinical and radiographic outcomes of bipolar hip arthroplasty with a cementless porous-coated anatomic femoral component.

METHODS

Fifty-nine patients (86 hips) with a minimum 3.5-year follow-up were followed up for a mean of 5.2 years (from January 2005 to January 2007). Standard clinical evaluation utilizing the Harris hip score and radiographic evaluation based on the criteria of the Hip Society were used in this prospective study. Radiographic assessment included evaluation of calcar remodeling and pedestal formation.

RESULTS

The average age of the patients (24 men and 35 women) at the time of surgery was 71.4 years (range, 69-84 years). The average preoperative Harris hip score was 48.5 ± 4.0 (range, 25-65) points, pain score 15.2 ± 3.9 (range, 0-20) points and functional score 26.7 ± 4.6 (range, 9-40) points. At the time of the latest follow-up, the average Harris hip score was 96.1 ± 2.1 (range, 67-100) points, pain score 42.6 ± 6.3 (range, 32-54) points and functional score 45.5 ± 4.7 (range, 29-56) points. Five hips (5.81%) had pain in the anterior part of the thigh. Two hips (2.33%) required revision of the femoral component because of aseptic loosening and periprosthetic fracture. Radiographic assessment revealed consistent evidence of proximal bone ingrowth. No completely radiolucent lines were identified, except around stems that had loosened. Twenty-seven femoral components (31.4%) had associated slight pedestal formation. No osteolytic lesions of the femur were identified. Nonprogressive pelvic osteolysis was identified in four hips, none of the lesions being ≥2mm in diameter.

CONCLUSION

An anatomically designed prosthesis can provide good clinical results, with low incidence of thigh pain and loosening of the component.