Partial meniscectomy is associated with increased risk of incident radiographic osteoarthritis and worsening cartilage damage in the following year

Roemer FW, Kwoh CK, Hannon MJ, Hunter DJ, Eckstein F, Grago J, Boudreau RM, Englund M, Guermazi A · European Radiology

Every one of the 31 knees that had a partial meniscectomy in the year before the case-defining visit developed radiographic osteoarthritis, and no control knee had had one: 8.8% of the knees that developed radiographic osteoarthritis, against 0%. A prevalent tear or maceration predicted it too — 165 of 280 such knees (58.9%) developed radiographic osteoarthritis, crude OR 2.51 (95% CI 1.73 to 3.64). The two part company on cartilage. Across cases and controls together, cartilage loss over that year was seen in 80.8% of knees with a partial meniscectomy and 37.4% of knees with meniscal damage but no surgery; restricted to knees that developed radiographic osteoarthritis and adjusted for the matching criteria, BMI and prevalent MRI features, meniscal damage alone carried OR 0.88 (95% CI 0.51 to 1.51) for worsening cartilage while partial meniscectomy carried OR 4.51 (95% CI 1.53 to 13.33).

Population

355 Osteoarthritis Initiative knees that developed radiographic osteoarthritis, each matched to a control knee, with MRIs read by the semi-quantitative MOAKS system

Intervention

Conditional logistic regression on partial meniscectomy in the year before the case-defining visit

Limitations

Observational and matched on incident osteoarthritis, and the whole surgical signal rests on 31 knees, 26 of them with imaging from the year before. Surgery was self-reported and then confirmed as missing meniscal substance on MRI. Operated knees had higher pain scores and more previous injuries, and the authors state they cannot fully rule out residual confounding by indication. The outcome is radiographic only, and the authors note that removing meniscal substance narrows the joint space directly, which feeds the diagnosis being made.