Prophylactic Regenerative Peripheral Nerve Interfaces in Elective Lower Limb Amputations

Abstract

Regenerative peripheral nerve interface (RPNI) is a relatively new surgical technique to manage neuromas and phantom pain after limb amputation. This study evaluates prophylactic RPNI efficacy in managing post-amputation pain and neuroma formation in amputees compared with patients in which lower limb amputation was performed without this procedure. We included 28 patients who underwent above the knee amputation (AKA) or below the knee amputation (BKA) for severe soft tissue infection from July 2019 till December 2020. All patients had insulin-dependent diabetes. The patients were divided into two groups, 14 patients with primary RPNI and 14 patients without. We analyzed the demographic data, level of amputation, number of RPNIs, operative time, postoperative complications and functional outcome on the defined follow up period. The mean patient age was 68.6 years (range 49–85), 19 (67.9 %) male and 9 (32.1 %) female patients. In this study 11 (39.3 %) AKA and 17 (60.7 %) BKA were performed. Overall, 37 RPNIs were made. The mean follow-up period was 49 weeks. PROMIS T-score decreased by 15.9 points in favor for the patients with RPNI. The VAS score showed that, in the RPNI group, all 14 patients were without pain compared to the group of patients without RPNI, where the 11 (78.6 %) patients described their pain as severe. Patients with RPNI used prosthesis significantly more (p < 0.005). Data showed significant reduction in pain and high patient satisfaction after amputation with RPNIs. This technique is oriented as to prevent neuroma formation with RPNI surgery, performed at the time of amputation. RPNI surgery did not provoke complications or significant lengthening of operative time and it should be furthermore exploited as a surgical technique.

Regenerative Peripheral Nerve Interface Surgery: Anatomic and Technical Guide

“…This plays a significant role in the development of chronic pain. Treating all other etiologies of peripheral nerve pain (ie, migraine headache and carpal tunnel syndrome) can also help reduce centrally-mediated pain [69][70][71][72][73] This proposes a future direction of RPNI surgery in that the treatment of peripherally-mediated pain associated with neuromas may have a role in mitigating centrally-mediated pain. In other words, RPNI may have benefit in treating amputation patients with phantom limb pain, even if there is no severe neuroma pain in the residual limb.…”

Peripheral Nerve Stimulation for the Treatment of Post-Amputation Pain: A Systematic Review

“…Given the paucity of evidence supporting conservative measures and conventional pharmacotherapy, additional modalities are needed to adequately manage the patient's PAP. Surgical interventions such as targeted muscle reinnervation and regenerative peripheral nerve interface may be more effective surgical options, [8][9][10] but PAP often remains difficult to treat. Therefore, clinicians caring for patients with PAP may consider PNS in their treatment algorithm.…”

“…6,7 Surgical interventions including targeted muscle reinnervation and regenerative peripheral nerve interface have demonstrated positive outcomes for both alleviation and prevention of PAP. [8][9][10] However, despite these measures, many patients with PAP fail to achieve adequate analgesia and experience undesirable adverse effects. 3,6,7,11 Given these challenges, the use of neuromodulation as an adjunct therapy has been of growing interest and has been explored with use spinal cord stimulation, 12 dorsal root ganglion stimulation, 13 and peripheral nerve stimulation (PNS).…”

“…Commonly used pharmacologic agents include gabapentinoids and serotonin and norepinephrine reuptake inhibitors, with some patients occasionally requiring long-term use of opioids 6,7 . Surgical interventions including targeted muscle reinnervation and regenerative peripheral nerve interface have demonstrated positive outcomes for both alleviation and prevention of PAP 8–10 . However, despite these measures, many patients with PAP fail to achieve adequate analgesia and experience undesirable adverse effects 3,6,7,11 .…”

Regenerative Peripheral Nerve Interfaces Effectively Prevent Neuroma Formation After Sciatic Nerve Transection in Rats

“…In the clinical study by Kubiak et al, 45 patients who received RPNI did not develop neuromas and only 51% had phantom limb pain, whereas six out of 45 patients in the control group developed neuromas and 91% had phantom limb pain. Several current clinical trials have confirmed the effectiveness of RPNI in the prevention of neuromas and phantom limb pain (Zimmermann, 2001 ; Pejkova et al, 2022 ).…”