Evaluation of RPNI for Symptomatic Neuromas in Lower Limb Amputees

Sponsor
Saglik Bilimleri Universitesi
Study ID
NCT07420192
Status
Recruiting
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Conditions

  • Lower Extremity Amputations
  • Neuropathic Pain
  • Phantom Limb Pain After Amputation
  • Residual Limb Pain
  • Symptomatic Neuroma

Eligibility Criteria

Sex
ALL
Age
18 Years - 70 Years
Healthy Volunteers
Not accepted

Interventions

  • Regenerative Peripheral Nerve Interface (RPNI) Surgery — PROCEDURE
    The surgical procedure is standardized as follows to preserve the residual limb (stump) anatomy: * Approach: An 8-10 cm incision is made on the lateral thigh. For transtibial (below-knee) amputees, the incision is placed approximately 15 cm proximal to the knee joint. For transfemoral (above-knee) amputees, it is placed 5-10 cm proximal to the distal end of the residual limb. * Nerve Dissection: The sciatic nerve is isolated, dissected, and transected at its most distal point. Subsequently, it is separated into the Common Peroneal and Tibial divisions. * Fascicular Separation: Based on nerve thickness, intraneural dissection is performed to split the Common Peroneal nerve into 1 or 2 fascicles, and the Tibial nerve into 2 to 4 fascicles. * Graft Harvesting: Autologous muscle grafts are harvested to wrap these created fascicles. The donor site is standardized by amputation level: Vastus Lateralis muscle for transtibial amputees and Biceps Femoris muscle for transfemoral amputees.

Study Details

This prospective, observational cohort study evaluates the long-term outcomes of Regenerative Peripheral Nerve Interface (RPNI) surgery in patients with major lower extremity amputations suffering from symptomatic neuromas. RPNI is a surgical technique where the transected nerve end is implanted into a free autologous muscle graft to serve as a physiological target for reinnervation. The study aims to objectively assess the reduction in mechanical hypersensitivity using Pressure Pain Threshold (PPT) measurements via a digital algometer. Additionally, it monitors subjective neuropathic pain levels, functional mobility, and prosthesis satisfaction over a 24-month follow-up period compared to pre-operative baselines.

Key Dates

First listed
Feb 19, 2026
Start date
Jan 20, 2026
Status verified
Feb 2026
Primary completion
Nov 30, 2029
Completion
Mar 31, 2030

Study Design

Enrollment
20 participants (estimated)

Arms

  • Arm: RPNI Group
    Adult patients (18-70 years) with unilateral major lower extremity amputations (transtibial or transfemoral) who are diagnosed with "Symptomatic Neuroma" confirmed by the clinical triad (DN4 score ≥4, positive Tinel sign, and diagnostic ultrasound). These patients are scheduled to undergo Regenerative Peripheral Nerve Interface (RPNI) surgery as part of the routine standard of care treatment protocol.

Primary Outcome Measure

Change in Pressure Pain Threshold (PPT) [ Time Frame: Baseline (Pre-op), 3, 6, 12, and 24 months post-operation. ]

Central Contacts

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