Neuromas and Persistent Postoperative Pain Following Total Knee Arthroplasty.

Purpose: Persistent postoperative knee pain after primary total knee arthroplasty (TKA) is often an indication for revision surgery and has a multifactorial etiology. Periarticular neuromas of nerves innervating the joint, ligaments, or overlying skin are important but misdiagnosed causes of persistent knee pain following knee surgery. This study aimed to characterize the incidence and sequelae of peripheral neuromas in TKA patients.

Methods: We utilized the TriNetX research network to identify TKA patients experiencing persistent knee pain lasting more than 3 months between 2016-2024, excluding cases with acute postoperative pain and implant-related causes, and identified patients diagnosed with neuromas. We then compared the rate of revision between patients with persistent knee pain with confirmed neuroma diagnoses and those without, and evaluated the utilization of surgical and nonsurgical interventions.

Results: Of 446,969 primary TKA patients, 111,533 (25.0%) experienced persistent pain, of whom 5785 (5.2%) were diagnosed with neuromas. Among those diagnosed, 19% received a diagnosis within 1 year of TKA, 25.8% between one and 3 years, and 55.2% after 3 years. Revision rates were similar in both groups (0.5% vs 0.5%). While 10.5% of neuroma patients received an intervention, only 3.6% underwent definitive surgical intervention.

Conclusions: One-fourth of TKA patients have persistent knee pain not associated with joint or implant-related factors, yet only around 5% are definitively diagnosed with a neuroma, suggesting potential underdiagnosis. The high risk of nerve injury during standard TKA incisions should warrant a high index of suspicion for neuromas in patients with refractory persistent knee pain.