This 2021 JAMA narrative review by Katz, Arant, and Loeser synthesizes epidemiology, pathophysiology, diagnosis, and treatment of hip and knee OA. It draws primarily on OARSI 2018 guideline meta-analyses to quantify treatment effect sizes using standardized mean differences. The review covers the full spectrum from clinical diagnosis to total joint replacement outcomes and emerging disease-modifying therapies.
A patient over 45 with use-related knee pain, morning stiffness under 30 minutes, bony enlargement on exam, and osteophytes on a standing weight-bearing radiograph has a diagnosis of OA — no MRI needed. The combination of pain plus osteophyte carries a likelihood ratio of 11.9 for knee OA and 8.9 for hip OA, making these among the most powerful diagnostic pairings in the outpatient setting.
Start with the proven triad: exercise (highest effect size at SMD 0.52 for knee), weight loss, and education. Add topical or oral NSAIDs if tolerated; reserve intra-articular steroids for monoarticular flares, knowing they lose efficacy by 3 months and may harm cartilage long-term. Avoid opioids. Their SMD is only ~0.20 and the toxicity profile (falls, respiratory depression, addiction) far outweighs any benefit.
Refer for total joint replacement when pain and function fail conservative measures. The outcomes data are compelling: ~90% of THR and ~80% of TKR recipients achieve substantial pain relief, and implants last 20 years in 90% of knee and 80% of hip cases.
Be alert to disparities: Black and Hispanic patients are 25% less likely to be offered joint replacement despite equivalent disease burden, and when they do undergo surgery they face higher complication rates. Recognizing and addressing this gap is part of delivering equitable care.
This 2021 JAMA narrative review by Katz, Arant, and Loeser synthesizes epidemiology, pathophysiology, diagnosis, and treatment of hip and knee OA. It draws primarily on OARSI 2018 guideline meta-analyses to quantify treatment effect sizes using standardized mean differences. The review covers the full spectrum from clinical diagnosis to total joint replacement outcomes and emerging disease-modifying therapies.
A patient over 45 with use-related knee pain, morning stiffness under 30 minutes, bony enlargement on exam, and osteophytes on a standing weight-bearing radiograph has a diagnosis of OA — no MRI needed. The combination of pain plus osteophyte carries a likelihood ratio of 11.9 for knee OA and 8.9 for hip OA, making these among the most powerful diagnostic pairings in the outpatient setting.
Start with the proven triad: exercise (highest effect size at SMD 0.52 for knee), weight loss, and education. Add topical or oral NSAIDs if tolerated; reserve intra-articular steroids for monoarticular flares, knowing they lose efficacy by 3 months and may harm cartilage long-term. Avoid opioids. Their SMD is only ~0.20 and the toxicity profile (falls, respiratory depression, addiction) far outweighs any benefit.
Refer for total joint replacement when pain and function fail conservative measures. The outcomes data are compelling: ~90% of THR and ~80% of TKR recipients achieve substantial pain relief, and implants last 20 years in 90% of knee and 80% of hip cases.
Be alert to disparities: Black and Hispanic patients are 25% less likely to be offered joint replacement despite equivalent disease burden, and when they do undergo surgery they face higher complication rates. Recognizing and addressing this gap is part of delivering equitable care.