NCT07092579

Smart Crutch Tips for Guided Weight-Bearing in Patients Recovering From Tibial Shaft Fractures

Study of Individual Weight-bearing and Iterative Walking Using "ComeBack Mobility" Smart Crutch Tips for Mechanical Stimulation of Tibial Shaft Fracture Healing.

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 30 (estimated)
• Sponsor: Comeback Mobility Inc · Industry
• Sex: All
• Age: 18 Years – 80 Years
• Healthy volunteers: Not accepted

Summary

The goal of this clinical trial is to learn whether personalized weight-bearing prescriptions using Smart Crutch Tips™ can improve recovery after surgery for tibial shaft fractures. The study will also assess how safe and practical this approach is in daily outpatient use. Can a personalized weight-bearing program based on CT and finite element analysis help the fracture heal faster? Can it help patients return to full weight-bearing sooner? Can it reduce the fear of movement during recovery? Does iterative walking in the early postoperative period support faster or better bone healing? Researchers will compare standard rehabilitation to different types of personalized weight-bearing programs to see which leads to faster healing, earlier mobility, and better outcomes. Participants will: Use Smart Crutch Tips™ during walking for up to 24 weeks; Follow a personalized weight-bearing prescription based on CT scans and biomechanical modeling; Follow a specific walking plan with real-time audio and visual feedback; Attend six follow-up visits over 36 weeks for clinical exams, x-rays, and CT scans; Complete online questionnaires about pain, activity, and fear of movement.

Detailed description

This is a pilot multicenter clinical trial designed to explore the impact of individual weight-bearing and iterative walking regimens on the healing of tibial shaft fractures. The study will enroll 30 adult participants (aged 18 to 80) with closed tibial shaft fractures (AO/OTA 42-A, 42-B, or 42-C) treated by intramedullary nailing and/or plate fixation. Participants will be allocated into three parallel groups (ten participants per group), two of whom will receive personalized weight-bearing protocols based on finite element analysis (FEA) performed using individual CT scan data. The goal of the study is to determine whether providing precise, data-driven weight-bearing recommendations-delivered through Smart Crutch Tips™ with real-time visual and auditory feedback-can enhance fracture healing by promoting safe interfragmentary motion. Group 1 (control - standard practice) will use Smart Crutch Tips™ for load data collection only, without feedback, and follow AO Foundation guidelines, progressing weight-bearing based on pain tolerance. Group 2 (controlled mechanical stimulation) will receive personalized FEA-based load prescriptions for optimal interfragmentary motion, with real-time audio/visual feedback from Smart Crutch Tips™. They will perform iterative walking sessions (minimum two-hour rest between), gradually increasing steps per their plan, plus prescribed lower limb strengthening exercises. Group 3 (optimized stimulation per Claes-Heigele theory) will receive FEA-based prescriptions targeting maximum fracture-zone voxel optimization, with real-time feedback. They will follow the same walking and exercise protocol as Group 2. Participants will use ComeBack Mobility Smart Crutch Tips™ all the time they use crutches in an outpatient setting for up to 24 weeks, depending on their healing progress. These devices provide real-time guidance to help users stay within their prescribed weight-bearing range and transmit data to a centralized monitoring platform. Participants will attend seven in-person follow-up visits: screening (Day 0-7), and then at 6, 12, 16, 20, 24, and 36 weeks after surgery. Аt each follow-up visit starting from Visit 1 (6 weeks) Radiographic assessments (X-ray) will be performed to monitor fracture healing, Computed tomography (CT) scans will be conducted only at specific time points: during the screening period (0-7 days post-surgery), and prior to Visit 1 (6 weeks), Visit 2 (12 weeks), and optional prior to Visit 3 (16 weeks) to adjust weight-bearing prescription and assess consolidation dynamics. Clinical data will be collected via the ComeBack Mobility app and electronic case report forms (eCRFs). Before each follow-up visit, participants will complete an online diary that includes validated questionnaires such as the Tampa Scale for Kinesiophobia (TSK-17) and the Lower Extremity Functional (LEFS). At Visit 1, participants will also complete the System Usability Scale (SUS) to assess their experience using the device. All study procedures will be conducted according to a standardized research protocol across multiple orthopedic hospitals and trauma centers in Ukraine, ensuring consistency in surgical technique, data collection, and follow-up.

Conditions

• Fracture Healing
• Tibial Fractures

Interventions

Type	Name	Description
DEVICE	Smart Crutch Tips™	Smart Crutch Tips™ are sensor-equipped crutch attachments that measure real-time axial loading during ambulation. The devices connect via Bluetooth to a mobile application and deliver auditory and visual feedback to guide patients toward prescribed weight-bearing levels. The devices continuously record loading and step-count data for clinical monitoring and analysis.
PROCEDURE	Finite Element Analysis (FEA)	Finite Element Analysis (FEA) is performed up to four times postoperatively to generate individualized weight-bearing prescriptions during rehabilitation. Simulations are based on CT scans and include segmentation and biomechanical modeling of the bone-fixator system. Assessments occur at: 7 days (baseline), 6 weeks, 12 weeks, and optionally at 16 weeks if healing isn't confirmed. Three regions are segmented: fixation system (screws and nail), bone fragments, and fracture gap. Materials: fixator (Titanium Grade 5), bone (mapped into cortical, trabecular, soft tissue, air), and fracture gap (early connective tissue). FEA calculates personalized safe loading based on: (1) Fixator safety (stress \< 290 MPa), (2) Interfragmentary motion (target: 0.5-2.0 mm), and (3) Strain in the fracture gap (octahedral: 0.001-0.05; hydrostatic: 0.001-0.02), supporting biological healing. Output informs weight-bearing prescriptions and step-count targets, delivered via Smart Crutch Tips™ with real-time fee
BEHAVIORAL	Iterative walking	Participants will perform iterative walking sessions as part of their rehabilitation program. These sessions will be repeated throughout the day, with a minimum 2-hour rest interval between sessions. Step count will be progressively increased over time, according to the individualized rehabilitation plan. In the intervention arms, walking sessions will be guided by real-time auditory and visual feedback from Smart Crutch Tips™.
PROCEDURE	Lower Limb Rehabilitation Exercise Program	A structured exercise program prescribed postoperatively to promote functional recovery after tibial shaft fracture surgery. Exercises target quadriceps, hamstrings, gluteal muscles, and ankle/foot mobility to maintain muscle tone, prevent stiffness, and improve circulation. The program includes isometric and dynamic exercises such as: static quadriceps and hamstring contractions, straight leg raises, hip abduction, knee extension, hamstring curls, heel slides, ankle dorsiflexion/plantarflexion, ankle inversion/eversion, ankle circles, toe spreading, and passive ankle stretching using a strap or towel. Exercises are performed in pain-free ranges with gradual progression in repetitions and sets according to the rehabilitation plan. Certain ankle and foot mobility exercises (dorsiflexion/plantarflexion) are also performed hourly during the day to prevent swelling and thrombosis.

Timeline

• Start date: 2025-10-28
• Primary completion: 2026-11-01
• Completion: 2027-02-15
• First posted: 2025-07-30
• Last updated: 2026-04-14

Locations

18 sites across 1 country: Ukraine