Brooker et al. prospectively reviewed 100 consecutive THA patients at Johns Hopkins to document how common heterotopic ossification (HO) is after hip replacement. They proposed a four-class radiographic grading system based on AP radiographs and assessed whether HO severity correlated with functional outcome using the Harris Hip Score.
When you see HO on a post-THA radiograph, the Brooker class tells you whether to act — and the answer is almost always no for Classes I through III. This paper established that only apparent bone ankylosis (Class IV) translates into meaningful functional loss. Classes I–III are radiographic findings, not clinical problems.
For patients with prior hip surgery heading into THA, flag the elevated HO risk. Both Class IV cases in this series had prior procedures. That history should prompt discussion of prophylaxis. Indomethacin or low-dose radiation. As part of the perioperative plan.
The current accepted HO incidence after THA is approximately 43%, more than double the 21% reported here. Partly because later studies used 1-year follow-up rather than 6 months. The Brooker classification itself has proven durable as the standard reporting tool despite over 15 alternative systems proposed since 1973.
Brooker et al. prospectively reviewed 100 consecutive THA patients at Johns Hopkins to document how common heterotopic ossification (HO) is after hip replacement. They proposed a four-class radiographic grading system based on AP radiographs and assessed whether HO severity correlated with functional outcome using the Harris Hip Score.
When you see HO on a post-THA radiograph, the Brooker class tells you whether to act — and the answer is almost always no for Classes I through III. This paper established that only apparent bone ankylosis (Class IV) translates into meaningful functional loss. Classes I–III are radiographic findings, not clinical problems.
For patients with prior hip surgery heading into THA, flag the elevated HO risk. Both Class IV cases in this series had prior procedures. That history should prompt discussion of prophylaxis. Indomethacin or low-dose radiation. As part of the perioperative plan.
The current accepted HO incidence after THA is approximately 43%, more than double the 21% reported here. Partly because later studies used 1-year follow-up rather than 6 months. The Brooker classification itself has proven durable as the standard reporting tool despite over 15 alternative systems proposed since 1973.