Background
This article examines predictors of subsequent total knee arthroplasty (TKA) within 6 months of nonoperative intervention based on (1) patient demographics; (2) knee osteoarthritis (OA) severity; and (3) various nonoperative treatments (cryoneurolysis with superficial or deep genicular nerve block, intra-articular [IA] hyaluronic acid injections, nonsteroidal inflammatory drug injections, IA-corticosteroids injections, or IA-triamcinolone extended-release [IA-TA-ER] injections).
Methods
Patients who had unilateral knee OA and received nonoperative intervention were identified in the Innovations in Genicular Outcomes Research registry between September 2021 and February 2024, identifying 505 patients. Baseline patient demographics were tabulated by knee OA severity as graded by Kellgren-Lawrence (KL) and nonoperative treatment, identifying patients who underwent TKA within 6 months. Predictors of TKA were identified using 20 potential demographic/clinical variables and calculating individual hazard ratios.
Results
Obesity and KL grade IV knees were significant predictors of TKA within 6 months of nonoperative treatment (P < .05). Age, sex, marital status, number of comorbidities, physical activity level, smoking status, insurance type, and baseline pain and functional scores were not associated with subsequent TKA. Overall, treatment type was also not linked to subsequent TKA, although pairwise comparison suggested use of IA-TA-ER was associated with a decreased conversion to subsequent TKA (P = .002).
Conclusions
Apart from obesity and KL grade IV knees, it remains challenging to identify which patients are at risk for conversion to subsequent TKA after nonoperative treatment. It appears IA hyaluronic acid and IA-TA-ER are most associated with decreased conversion to TKA within 6 months.