Table 5: Occurrence of thumb carpometacarpal (CMC) joint osteoarthritis (OA) by stages.

𝑁 =%

Stage 1 2234
Stage 2 1320
Stage 3 1422
Stage 4-516 25
No CMC joint OA35

𝑁 = 1 0 0 , the percentages pertain to number of radiographs by stage out of the 65 radiographs that had thumb CMC joint arthritis.