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

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.

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

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™.

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.