Total knee arthroplasty (TKA) is a reliable and widespread solution for knee osteoarthritis treatment, but about 20% of the patients complain of persisting pain. Neuroma formation in the IPBSN (infrapatellar branch of the saphenous nerve) is an undervalued cause of persistent anterior pain after TKA.
Alessio Giannetti et al conducted a study to evaluate the effectiveness of the selective neuroma denervation on patients satisfaction and pain improvement. This study is a clinical series of patients evaluated and treated in the Orthopedic Department of San Salvatore Hospital, L’Aquila, Italy. The article has been published in ‘The Knee’ journal.
The authors evaluated 13 patients suffering from persistent anterior knee pain and numbness after TKA who underwent a surgical neurectomy of the IPBSN. After clinical assessment and diagnosis confirmation, the authors carried out the surgery. Short Form 12 Health (SF12), Oxford Knee Score (OKS), and Numeric Rating Scale (NRS) have been collected before and after the procedure. After the surgical treatment, the symptom’s resolution and patients’ satisfaction were attested by the achievement of the Minimal Clinically Important Difference (MCID) of the self-administered patient-reported outcome measures (PROMs).
The results showed a statistically significant improvement (p < 0.05) of patients pain perception (mean NRS improvement –4.2, SD 2.5) and overall satisfaction (with a mean increase in OKS of 14.5 points SD 9.4, and in SF12 of 6.5 points SD 4.0).
In particular, the greatest improvement was observed on the SF12 Physical subscale, increased from 9 (±1.3) to 13.1 (±2.3) (p = 0.0019).
The authors concluded that – “The IPBSN is at risk for iatrogenic damage in any surgery on the anteromedial aspect of the knee, especially when longitudinal incisions are used. The neuroma that could result from this damage is an under-estimated source of persistent anterior pain. Our suggestion is to consider neuroma of the IPBSN as a differential diagnosis in order to avoid an unnecessary revision surgery. Despite its limitations, our study suggests that selective neuroma denervation provides a better outcome than local injective treatments and often results as a complete pain resolution. Multicentric studies, with bigger samples, should further investigate the data collected regarding the real incidence of the disease, its correct diagnosis and its impact on the quality of life of patients.”
Further reading:
Painful total knee arthroplasty: Infrapatellar branch of the saphenous nerve selective denervation. A case series
Alessio Giannetti, Luigi Valentino et al
The Knee 39 (2022) 197–202
https://doi.org/10.1016/j.knee.2022.09.010