Smart Crutch Tips for Guided Weight-Bearing in Patients Recovering From Extra-Articular Distal Tibia 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 15 weeks. 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.

The program consists of a structured set of isometric and dynamic exercises targeting the quadriceps, hamstrings, gluteal muscles, and ankle/foot mobility. Exercises are performed in a supine, prone, or seated position, as appropriate, with 2 sets of 5-12 repetitions or sustained holds of 20-30 seconds, progressing gradually according to the rehabilitation plan. All movements are conducted within a pain-free range (not exceeding 4/10 on the VAS scale), with additional hourly ankle mobility work prescribed to reduce swelling and prevent thrombosis.

Patients are provided with orthopedic shoes to be worn during the rehabilitation period (up to 6-10 weeks).