Because chondrocalcinosis can be taken as evidence of ‘inflammatory arthritis’, preoperative radiographic calcification in the menisci and the articular cartilage, or calcified deposits seen at arthrotomy, have been deemed to be contraindications to unicompartmental replacement (Kozinn et al., 1989). Two studies have looked at the influence of chondrocalcinosis on the outcome of OUKA. In the first study (Woods et al. 1995)3 of 96 patients with Phase 1 or Phase 2 OUKA there were 20 knees with histologically proven chondrocalcinosis (HCCK). There was no difference in clinical outcome or 10-year survival between those with or without chondrocalcinosis. In the second study (Kumar et al., 2017) using Phase 3 OUKA, 88 patients with radiographically diagnosed chondrocalcinosis (RCCK) and 67 with histological chondrocalcinosis were matched to control patients without chondrocalcinosis. RCCK was not associated with any difference in outcome score or survival, whereas HCCK was associated with significantly greater improvement in OKS but a lower survival. It is difficult to know how to interpret the data relating to HCCK and further study is needed. However, when assessing patients for OUKA, the diagnosis of chondrocalcinosis is made radiographically, based on the appearance of calcification seen in the menisci or articular cartilage. As RCCK is not associated with a worse outcome we do not consider the presence of chondrocalcinosis to be a contraindication.
