Brooker Classification (Heterotopic Ossification)
The Brooker classification of heterotopic (ectopic) ossification about the hip, by the radiographic extent of ectopic bone, classes I/II/III/IV.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Brooker class
- II - spurs, >= 1 cm gap between surfaces
Result: Brooker class II: bone spurs leaving at least 1 cm between opposing bone surfaces.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Class I
- Islands of bone within the soft tissues about the hip.
- Class II
- Bone spurs leaving at least 1 cm between opposing bone surfaces.
- Class III
- Bone spurs reducing the space between opposing surfaces to less than 1 cm.
- Class IV
- Apparent bony ankylosis of the hip.
What you enter
- Brooker class
How this is calculated
Brooker AF, Bowerman JW, Robinson RA, Riley LH Jr. Ectopic ossification following total hip replacement. Incidence and a method of classification. J Bone Joint Surg Am. 1973;55(8):1629-1632. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.