Ankylosing Spondylitis of the hip Wheeless

Description: hip joint:
- is affected in upto 50 % of patients with AS, and when it occurs it is often bilateral;
- protrusio and hip flexion contractures are common;
- heterotopic ossification may follow THR;
- total hip replacement:
- hetertopic ossification;
- occurs in 20-40 % of hip replacements and is more common w/ trochanteric osteotomy;
- to avoid heterotopic ossification consider insertion of a cemented acetabular component followed by 750 rads around the component;
Wheeless' Textbook of Orthopaedics