Subchondroplasty is a minimally-invasive technique which has been used for the treatment of subchondral lesions (e.g. insufficiency fractures) of the knee and ankle. The theoretical aim is to bolster subchondral bone architecture in order to prevent further collapse and progression of osteoarthritis .
The procedure is typically performed percutaneously, and involves injection of 5 to 16 mL of synthetic calcium phosphate filler material into the subchondral bone approximately 5 to 10 mm deep to the articular surface . The injection is performed under under fluoroscopic guidance to confirm positioning and avoid extravasation of filler into unwanted spaces .
- local post-procedure pain - tends to resolve
- filler extravasation
- deep venous thrombosis
- osteomyelitis - at least one case reported
- ill-defined zone of sclerosis corresponds to area of filler injection
- drill hole may remain visible
- extravasated injectate may extend into the soft tissues or intra-articular, and should be not be confused for heterotopic ossification. These may resolve over time
- injectate appears as focal hypointensity, similar to vertebroplasty cement
- in the first 6 months after treatment, injection may be surrounded by thin rind of hyperintensity on fluid-sensitive sequences
There is limited data on the effectiveness of subchondroplasty for treatment of painful osseous lesions, with mixed results .