Revision of Total Hip Arthroplasty Using Extensively Porous-Coated Femoral Stem

ABSTRACT

Purpose: To report the outcomes of extensively porous-coated femoral stems based on diaphyseal fixation caused by extensive bone loss and osteoporosis of the proximal femur in revision total hip arthroplasty. Materials and Methods: 14 cementless femoral revision procedures performed between Aug, 2000 and Apr, 2003 were reviewed retrospectively. The follow up period ranged from 24 to 53 months, with an average of 33 months. The average age at surgery was 52.3 years, there were 10 males and 4 females. The reasons for the revision surgery were aseptic loosening in 11(78.7%) hips, progressive osteolysis in 1(7.1%), septic loosening in 1(7.1%) and periprosthetic fracture in 1(7.1%). Results: The Harris hip score improved from 50.4 points preoperatively to 88.5 points postoperatively. The complications encountered were a greater trochanteric fracture in 2 hips (14.3%), periprosthetic fracture in 1(7.1%), dislocation of the hip in 2(14.3%), and minimal thigh pain in 2(14.3%). Radiographic evidence of a bone ingrown stem was found in 11 hips (78.6%), and 3 hips (21.4%) showed stable fibrous fixation. Stem subsidence > 5mm was noticed in 1 hip (7.1%) and > 10mm in 2 (14.3%) but there was no further progression after 1 year. Moderate stress-shielding was noticed in 4 hips(28.6%). To date, no significant wear or osteolysis has been observed. Conclusion: An extensively porous-coated revision stem appears to be a reasonable choice in the presence of proximal femoral bone loss as a short term follow up. However, the concerns related to the postoperative complications will require a longer term follow up.