Regenerative Peripheral Nerve Interfaces for the Treatment of Painful Neuromas in Major Limb Amputees

Study Summary

The Regenerative Peripheral Nerve Interface (RPNI) is a novel strategy to prevent neuroma formation in transected peripheral nerves. The RPNI consists of a residual peripheral nerve that is implanted into a free skeletal muscle graft either at the time of limb amputation or after excision of a terminal neuroma bulb. The sprouting axons of the nerve readily reinnervate the free muscle graft, thereby greatly reducing the chance of neuroma formation. This investigation has a prospective cohort study design involving major lower limb amputees drawn from both the University of Michigan Health Systems and VA Health System of Ann Arbor. To objectively evaluate the effect of RPNI surgery on patients' perception of pain and to measure other health-related quality of life metrics relating to neuroma pain, this clinical trial will utilize specific, validated patient-reported outcomes measures (PROMs) to assess targeted domains in patients with major limb amputation. These survey instruments will determine: 1) patterns of pain medication use, including the use of opioids, 2) functional status and use of a prosthetic device, 3) changes in neuroma pain quality, 4) limitations in activities of daily living due to neuroma pain, 5) depression and anxiety relating to neuroma pain.

Primary Outcome

The OPUS was a self-report questionnaire consisting of five modules. It can be used for prosthetic and orthotic programs for quality assessment, to maintain awareness of improvement in activities, to evaluate changes in patient's functional status and quality of life, and to assess satisfaction with devices and services. This study used the Functional Status Measure module, which was a 20-question survey that used a Likert scale ranging from 1 (very easy) to 5 (cannot do this activity).

Interventions

• PROCEDURE Amputation with Regenerative Peripheral Nerve Interfaces (RPNI)
• OTHER Amputation Without RPNI