NCT07324109

Clinical Application Observation on the Evaluation of Phantom Limb Pain With the Suralis System

Clinical Application Observation: Evaluation of Phantom Limb Pain After 3 Weeks of Use of a Feedback System Using Vibration (Suralis, Manufacturer: Saphenus)

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 20 (estimated)
• Sponsor: Median · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study tests whether a vibration-based feedback device (Suralis) can reduce phantom limb pain in people with lower-leg amputations over 3 weeks. Participants wear the device daily and report pain levels, walking ability, and quality of life - with no known risks, as it's a CE-certified medical device. If pain improves, the study team will help participants apply for insurance coverage to keep using the system long-term. The goal is to offer a simple, non-drug option that may help ease chronic pain and improve daily function for amputees. Participation is voluntary and can be stopped anytime without affecting medical care.

Detailed description

This observational, prospective, single-arm pilot study evaluates the short-term effects of the Suralis vibrotactile feedback system (Saphenus Medical Technology GmbH) on phantom limb pain intensity, gait stability, and perceived quality of life in individuals with unilateral lower-limb amputation. The Suralis system consists of a sensorized insole with four pressure-sensitive zones (toe, forefoot, midfoot, heel), each mapped to a corresponding vibrotactile actuator embedded in a thigh-mounted cuff. Vibration parameters - including onset threshold, intensity (0-100 % amplitude), duration (50-500 ms), and spatial mapping - are individually calibrated via a proprietary iOS/Android app, allowing for personalized somatosensory substitution. The system operates autonomously during ambulation. The study protocol includes a 3-week baseline phase to confirm persistent phantom pain (VAS ≥ 3/10 daily), followed by 3 weeks of active intervention, and a 3-week washout/follow-up phase to assess sustainability of effects. All assessments are conducted at the study center and include standardized functional tests (TUG, 6MWT), validated German-language questionnaires (DSF, VR-12, DASS, FW7, GCPS), and daily VAS entries captured via paper-based diaries. The system's CE-marked status (UDI: FBS 1 912012142) confirms conformity with EU MDR 2017/746 for Class IIa medical devices; no adverse events related to device use have been reported in prior clinical use. The study design incorporates no control group or randomization, reflecting its exploratory, real-world application focus. Statistical analysis will be descriptive and exploratory, with non-parametric methods applied to ordinal outcomes (Friedman test) and parametric or non-parametric repeated-measures analyses for continuous variables, depending on distribution. No blinding is feasible due to the nature of the intervention. All procedures comply with the Declaration of Helsinki and have been reviewed by the Ethics Committee of the Hessian Medical Association (approval pending).

Conditions

• Phantom Limb Pain After Amputation
• Lower Limb Amputation Above Knee
• Lower Limb Amputation Below Knee
• Lower Limb Amputation Knee

Interventions

Type	Name	Description
DEVICE	Vibrotactile sensory feedback	The Suralis system delivers real-time vibrotactile feedback via four pressure sensors embedded in a prosthetic insole, each mapped to a corresponding vibration motor on a thigh cuff. Participants wear the device during daily ambulation for 3 weeks. Vibration parameters (threshold, intensity, duration, spatial mapping) are individually calibrated via a smartphone app to match each user's sensory perception and gait pattern. The system operates autonomously, requires daily charging, and logs usage data via Bluetooth. No additional therapy or medication is administered alongside the device. The intervention aims to modulate cortical reorganization and reduce phantom limb pain while improving gait confidence and safety, particularly under non-visual conditions (e.g., stepping backward or sideways). The device is CE-marked (UDI: FBS 1 912012142) and classified as a Class IIa medical device under EU MDR 2017/746.

Timeline

• Start date: 2025-04-01
• Primary completion: 2026-07-31
• Completion: 2026-07-31
• First posted: 2026-01-07
• Last updated: 2026-01-07

Locations

1 site across 1 country: Germany