Results of Nerve Surgery to Treat PostAmputation Pain

Rationale: Postamputation pain (PAP) is frequently seen after amputations and is a severe lifelong disabling condition affecting quality of life (QoL). Different nerve surgical techniques are available to treat PAP if non-surgical treatment options are not sufficient. Multiple techniques have been described for treatment of symptomatic neuromas with varying results. Techniques described include traction neurectomy with/without implantation, nerve grafting, nerve capping, regenerative peripheral nerve interface, and targeted muscle reinnervation (TMR). In the Leiden University Medical Center (LUMC), the most common techniques to treat painful neuromas include TMR and fascicular split (FS). TMR involves coaptating the transected mixed nerve to functional motor nerves, showing promising results in recent studies. FS is a technique closely related to neurectomy with implantation in a functional muscle. The difference is that with FS, the nerve is split into fascicles before implantation to allow for better distribution of nerve fibers. These techniques have not yet been compared. In this study, the investigators will compare both these techniques in a prospective setting for the treatment of PAP. The hypothesis is, that after 12 months, pain will be diminished and QoL will be increased in all patients versus the pre-operative status. There will be little to no difference in outcome between the surgical techniques used. Objective: To evaluate limb pain in patients with intractable postamputation pain (residual limb pain and phantom limb pain) one year after nerve embedding surgery following the standardized workup of the LUMC. Study design: Prospective study Study population: Patients 18 years of age or older, with a history of more than 6 months of intractable postamputation neuropathic limb pain, with no history of previous surgical intervention for pain treatment, referred to the Leiden Nerve Center. Main study parameters/endpoints: The mean difference in pain scores for phantom limb pain and residual limb pain one year postoperatively. An average pain score from the past 7 days is used for PLP and RLP individually, on the 11-point (0-10) numerical rating scale (NRS). Additionally, the Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Behavior and Interference Questionnaire Short Forms (7a and 8a, respectively) are used one year postoperatively. Nature and extent of the burden and risks associated with participation, benefit, and group relatedness: Both techniques are currently used in the Leiden University Medical Center (LUMC) and considered standard of care. The decision to perform either technique is solely dependent on the personal preference of the treating nerve surgeon. The results of this trial will improve the understanding of the treatment effect of both surgical techniques with a minimal patient burden. Participation requires patients to complete 3-4 non-invasive questionnaires about pain, quality of life, depression and anxiety, and mobility over a period of 2 years. The pre-operative (if applicable) and 12-month postoperative questionnaire will each take approximately 15 minutes to complete. The other two questionnaires at 18 and 24 months postoperative will take approximately 3-4 minutes to complete. Additionally, participants will fill out a daily questionnaire consisting of one to three questions about pain for 7 consecutive days at 12 months.