Prevalence of post-traumatic neuropathic pain after digital nerve repair and finger amputation.

INTRODUCTION: Post-traumatic neuropathic pain is a major factor affecting the quality of life after finger trauma and is reported with considerable variance in the literature. This can partially be attributed to the different methods of determining neuropathic pain. The Douleur Neuropathique 4 (DN4) has been validated to be a reliable and non-invasive tool to assess the presence of neuropathic pain. This study investigated the prevalence of neuropathic pain after finger amputation or digital nerve repair using the DN4 questionnaire. METHODS: Patients with finger amputation or digital nerve repair were identified between 2011 and 2018 at our institution. After a minimal follow-up of 12 months, the short form DN4 (S-DN4) was used to assess neuropathic pain. RESULTS: A total of 120 patients were included: 50 patients with 91 digital amputations and 70 patients with 87 fingers with digital nerve repair. In the amputation group, 32% of the patients had pain, and 18% had neuropathic pain. In the digital nerve repair group, 38% of the patients had pain, and 14% had neuropathic pain. Secondly, of patient-, trauma-, and treatment-specific factors, only the time between trauma and surgery had a significant negative influence on the prevalence of neuropathic pain in patients with digital nerve repair. CONCLUSION: This study shows that persistent pain and neuropathic pain are common after finger trauma with nerve damage. One of the significant prognostic factors in developing neuropathic pain is treatment delay between trauma and time of digital nerve repair, which is of major clinical relevance for surgical planning of these injuries.

Prevention is better than cure: Surgical methods for neuropathic pain prevention following amputation - A systematic review.

BACKGROUND: Pain after amputation can be known as residual limb pain (RLP) or phantom limb pain (PLP); however, both can be disabling in daily life with reported incidences of 8% for finger amputations and up to 85% for major limb amputations. The current treatment is focused on reducing the pain after neuropathic pain occurs. However, surgical techniques to prevent neuropathic pain after amputation are available and effective, but they are underutilized. The purpose of the review is to investigate the effects of techniques during amputation to prevent neuropathic pain. METHODS: A systematic review was performed in multiple databases (Embase, Medline, Web of Science, Scopus, Cochrane, and Google Scholar) and following the PRISMA guidelines. Studies that reported surgical techniques to prevent neuropathic pain during limb amputation were included. RESULTS: Of the 6188 selected studies, 13 eligible articles were selected. Five articles reported techniques for finger amputation: neurovascular island flap, centro-central union (CCU), and epineural ligatures, and flaps. For finger amputations, the use of prevention techniques resulted in a decrease of incidences from 8% to 0-3% with CCU being the most beneficial. For major limb amputations, the incidences for RLP were decreased to 0 to 55% with TMR and RPNI and compared to 64-91% for the control group. Eight articles reported techniques for amputations on major limbs: targeted muscle reinnervation (TMR), targeted nerve implantation, concomitant nerve coaptation, and regenerative peripheral nerve interface (RPNI). CONCLUSIONS: Based on the current literature, we state that during finger and major limb amputation, the techniques to prevent neuropathic pain and PLP should be performed.