Femoral revision hip arthroplasty: Modular versus nonmodular femoral component for severe femoral deficiency

• Published in: Operative techniques in orthopaedics Vol. 10; no. 2; pp. 133 - 137
• Main Authors: Shilling, Jack W., Sharkey, Peter F., Hozack, William J., Rothman, Richard H.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 2000
• Subjects: femur; modular; revision; modular; femur; revision
• ISSN: 1048-6666; 1558-3848
• DOI: 10.1016/S1048-6666(00)80018-X

Modularity of the femoral component has certain theoretical advantages for replacement of a severely deficient or deformed femur. Independent sizing and fitting of the proximal and distal femur may allow for secure fixation. However, it is unproved whether the clinical results of these cases are improved with a modular stem. This study evaluated the overall results of femoral revision in a severely bone deficient femur using modular and nonmodular versions of an otherwise identical calcar-bearing, cementless femoral component. Thirty-four femoral revision hip arthroplasties using a nonmodular design and 30 femoral revision hip arthroplasties using a modular design of an otherwise identical calcar-bearing, cementless, porous-coated femoral component were evaluated at follow-up of 3.8 and 3.0 years, respectively. All hips showed severe type III bone changes according to Mallory's classification system. Strut allograft or proximal femoral allografts were used in all cases for reconstruction. In the nonmodular revision group, the Harris Hip Score increased modestly from a preoperative mean of 34 to a postoperative mean of 79. An intraoperative femoral split occurred in 12% of these cases, at the time of implantation. In addition, 30% of the patients developed thigh pain, 9% showed evidence of aseptic loosening, and 6% required additional revision surgery for aseptic loosening. With the modular femoral prosthesis, the Harris Hip Score increased from a preoperative mean of 42 to a postoperative mean of 89. An intraoperative femoral split occurred in 6% of these procedures and 6% developed thigh pain. There were no cases of aseptic loosening or rerevision with the modular components. In cases of type III femoral bone loss, a modular femoral component has advantages over its nonmodular counterpart. This study compared two virtually identical femoral component designs and demonstrated superior clinical results using a modular femoral component for severe femoral defects. Therefore, we recommend using modular femoral components in these difficult revision situations.