Excision of the proximal femur for tumour with
prosthetic reconstruction using a bipolar femoral head places a considerable
load on the unreplaced acetabulum. We retrospectively reviewed the changes which occur around the
affected hip joint by evaluating the post-operative radiographs
of 65 consecutive patients who underwent proximal prosthetic arthroplasty
of the femur, and in whom an acetabular component had not been used.
There were 37 men and 28 women with a mean age of 57.3 years (17
to 93). Radiological assessment included the extent of degenerative
change in the acetabulum, heterotopic ossification, and protrusio
acetabuli. The mean follow-up was 9.1 years (2 to 11.8). Degenerative changes
in the acetabulum were seen in three patients (4.6%), Brooker grade
1 or 2 heterotopic ossification in 17 (26%) and protrusion of the
prosthetic head in nine (13.8%). A total of eight patients (12.3%) needed a revision. Five were
revised to the same type of prosthesis and three (4.6%) were converted
to a total hip arthroplasty. We conclude that radiological evidence of degenerative change,
heterotopic ossification and protrusion occur in a few patients
who undergo prosthetic arthroplasty of the proximal femur for tumour.
The limited extent of these changes and the lack of associated symptoms
do not justify the routine arthroplasty of the acetabulum in these patients. Cite this article: