Table 1.

Charnley classification including modification of group B

A	Single-joint arthropathy and no significant medical comorbidity
B	One other joint in need of an arthroplasty, or an unsuccessful or failing arthroplasty in another joint
B1	Contralateral hip in need of arthroplasty, but untreated
B2	Contralateral hip has been successfully treated with an arthroplasty
C	Multiple joints in need of arthroplasty, multiple failing arthroplasties or significant medical or psychological impairment