Abstract
One of the many challenges in revision hip arthroplasty is massive bone loss. Subsidence of the collarless stem with impaction allografting has been reported by several authors. Impaction grafting has emerged as a useful technique in the armamentarium of the revision total hip arthroplasty surgeon. The original technique proposed by Ling has been associated with complications, including femoral shaft fractures, recurrent dislocations, and uncontrolled component subsidence. Modifications in that technique seem to be associated with a reduction in complications.
The aim of this study was to assess the functional outcome of radial impaction grafting in femoral bone defects and the use of collared long stem prosthesis.
A total of 107 patients underwent radial impaction allografting and collared long stem prosthesis during revision THA between 1997 and 2005. The patients with Paprosky type II, IIIA and IIIB defects were included in this study. Average duration between the primary and revision surgery was 9.4 years (Range 6–23 years). Assessment was done using Oxford Hip Score, Harris Hip Score and with plain X-rays. Three patients were lost to follow-up and three patients died due to unrelated causes.
The follow-up period lasted between 12 to 114 months (average – 68.8 months). Three patients who sustained post-operative peri-prosthetic fracture had standard stem inserted in them. None of the patients with long stem sustained peri-prosthetic fracture. Four patients had infection and underwent revision procedure. In this study, using revision for any cause as the end-point, survival of the femoral stem was 93.8%. Subsidence was not recorded in any of the patients in this study. Oxford Hip Score improved from mean pre-operative value of 41.2 to 19.2 post-operatively. Mean Harris Hip Score improved from 40.8 pre-operatively to 83.4 post-operatively.
Subsidence of the prosthesis is commonly encountered with collarless stems and this was not a problem in this study. The risk of peri-prosthetic fracture can be reduced by using long stem prosthesis which bypasses the existing cement mantle by at least two femoral diameters. The radial impaction grafting technique permits the use of revision femoral components with variable stem lengths, neck lengths, and neck offsets.
We conclude that radial imaction graftind along with collared long stem prosthesis is a good solution for massive femoral bone defects while performing total hip arthroplasty.
Correspondence should be addressed to BHS c/o BOA, at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London, WC2A 3PE, England.
