Fracture HealingNCT07092579
Smart Crutch Tips for Guided Weight-Bearing in Patients Recovering From Tibial Shaft Fractures
A study testing Smart Crutch Tips™, Finite Element Analysis (FEA) and Iterative walking in people with Fracture Healing and Tibial Fractures, run by Comeback Mobility Inc at 18 sites in Ukraine.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- Fracture Healing, Tibial Fractures
- What is being tested?
- Smart Crutch Tips™, Finite Element Analysis (FEA) and Iterative walking
- Type of treatment
- Medical device, Surgery or procedure, Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 18 sitesUkraine
- Study dates
- 28 Oct 2025to 15 Feb 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Signed informed consent was provided after being fully informed about participation in the study.
- Age: 18 to 80 years for both males and females (pre-menopausal).
- Body weight between 40 and 120 kg.
- Body Mass Index (BMI) between 18.5 and 29.9 kg/m².
- Diagnosed with a closed tibial shaft fracture (AO/OTA classification: 42-A, 42-B, or 42-C) requiring surgical treatment.
- Fracture treated exclusively with intramedullary nailing and/or plate fixation
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- No diabetes or well-controlled diabetes (HbA1c ≤ 7.0%).
- Ability to use crutches without losing balance and medically cleared for partial weight-bearing on the operated limb.
- Willingness to adhere to the prescribed weight-bearing protocol using the Smart Crutch Tips™ device.
- Enrollment within 48 hours following surgical intervention.
- Alcohol consumption (up to 2-3 times per week) within acceptable limits.
- Willingness to comply with all study procedures, including follow-up visits at weeks 1, 6, 12, 16, 20, 24 and 36 after surgery.
- Patients with fractures extending into the articular surface of the distal tibial epiphysis may be included, provided that the fracture is deemed stable
Who cannot join
- Presence of open or high-energy fractures, multiple lower-limb fractures, or use of bone grafts.
- Fractures classified as 43-B or 43-C according to AO/OTA.
- Chronic alcoholism (defined as >14 standard drinks per week for men or >7 for women).
- Presence of metabolic disorders, including uncontrolled thyroid dysfunction, severe renal or hepatic pathology.
- Pathological fractures associated with osteoporosis, osteomyelitis, tumors, metastases, or rickets.
- Lower-limb contractures with functional impairment of grade II or higher.
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- Pregnancy or intention to conceive during the study period.
- Psychiatric, cognitive, or neurological disorders that may interfere with adherence to the rehabilitation protocol or effective communication with the study team.
- Clinically significant heart failure (including chronic or acute, with an ejection fraction <40% or with symptoms such as edema, dyspnea at rest, or orthopnea).
- Pulmonary insufficiency of any origin, accompanied by chronic hypoxemia (PaO₂ < 60 mmHg) or hypercapnia (PaCO₂ > 45 mmHg), requiring oxygen support or significantly limiting physical activity.
- Clinically significant neurological disorders that may affect motor function, coordination, or physical activity (e.g., stroke with residual deficits, Parkinson's disease, multiple sclerosis, cerebral palsy).
- Diagnosed epilepsy or other seizure disorders not fully controlled by medication.
- Progressive neurodegenerative diseases (e.g., amyotrophic lateral sclerosis, Huntington's disease, dementia).
- Any sensory, balance, or vestibular disorders that may impair safe use of the investigational device.
- Participation in another clinical study within the past 6 months that could affect the results of the current study.
- Ongoing or planned use of medications known to affect bone healing.
Trial locations and contacts
18 sites in 1 country. Contact the study team or a site near you to ask about taking part.
18 sites in 1 country
Ukraine18 sites, 18 recruiting
- Recruiting
Municipal Clinical Hospital No. 4 of the Dnipro City Counci
Dnipro, 49102
Oleksii Altanets, +380505757354, alexaltan80@gmail.com
Oleksii Altanets
- Recruiting
Communal Non-Profit Enterprise "Regional Family Health Medical Center" of the Dnipropetrovsk Regional Council
Dnipro
Vitalii Kravchenko, +380981779470, Dr.vitalii.kravchenko@gmail.com
- Recruiting
Municipal Non-Profit Enterprise "City Clinical Hospital No. 16" of the Dnipro City Council
Dnipro
Vasyl Makarov, 380675673081, vasylmakarov2010@gmail.com
Vasyl Makarov, PhD
- Recruiting
Municipal Non-Profit Enterprise of the Dnipro Regional Council "Dnipro Regional Clinical Hospital named after Mechnikov"
Dnipro
Maksym Makarenkov, +380508847654, 1798_010@email.dp.ua
- Recruiting
University Hospital of the Dnipro State Medical University
Dnipro
Andrii Mametiev, +380977800649, mametev75@gmail.com
- Recruiting
Municipal Non-Profit Enterprise "Ivano-Frankivsk Regional Clinical Hospital of the Ivano-Frankivsk Regional Council"
Ivano-Frankivsk
Vadym Sulyma, +380505035279, vadymsulyma11@gmail.com
- Recruiting
Kyiv City Clinical Hospital No. 1
Kyiv, Kyiv Oblast, 02091
Oleksandr Martynchuk, +380662272790, blaze_amber@ukr.net
Oleksandr Martynchuk
- Not yet recruiting
Railway Clinical Hospital No. 1 of Kyiv Station
Kyiv, 01030
Oleh Lehenkyi, +380503803958, legenky@i.ua
Oleh Lehenkyi
- Recruiting
Kyiv City Clinical Hospital No. 17
Kyiv, 01133
Maksym Cherniienko, +380633838714, maximchernienko79@gmail.com
Maksym Cherniienko
- Not yet recruiting
Institute of Traumatology and orthopedics of the national academy of medical sciences of Ukraine
Kyiv, 01601
Oleksii Sulyma, +380675010661, sulymaoleksii@gmail.com
Oleksii Sulyma
- Recruiting
Kyiv City Clinical Hospital No. 12
Kyiv, 02000
Taras Kasianchuk, +380966056181, kasyanchuk09@gmail.com
Taras Kasianchuk
- Recruiting
Kyiv City Clinical Hospital No. 7
Kyiv, 03179
Oleksandr Rozsokha, +380930600000, rassokha.doctor@gmail.com
Oleksandr Rozsokha
- Recruiting
Kyiv Regional Council "Kyiv Regional Clinical Hospital"
Kyiv, 04106
Vadym Roienko, +380976430314, vroienko@mail.com
Vadym Roienko
- Recruiting
Kyiv City Clinical Hospital No. 9
Kyiv, 04112
Pavlo Honcharuk, +380500569033, pavlo.medicina@gmail.com
Pavlo Honcharuk
- Recruiting
Kyiv City Clinical Hospital No. 8
Kyiv, 04201
Viktoriia Ladyka, +380634957408, ladika62@ukr.net
Viktoriia Ladyka
- Recruiting
State Institution "Feofaniya Clinical Hospital of the State Administration of Affairs"
Kyiv
Ihor Zazirnyi, +38 067 756 3247, zazirny@ukr.net
- Recruiting
Municipal Non-Profit Enterprise "Lviv Territorial Medical Association" "Multidisciplinary Clinical Hospital for Intensive Treatment Methods and Emergency Medical Care"
Lviv
Yurii Kit, +380667218903, Yura.kit190@gmail.com
- Recruiting
Municipal Non-Profit Enterprise "Lviv Territorial Medical Association" "Multidisciplinary Clinical Hospital for Intensive Treatment Methods and Emergency Medical Care"
Lviv
Vasyl Rokyta, +38097616803, vasylrokyta@gmail.com
About this study
Official title: Study of Individual Weight-bearing and Iterative Walking Using "ComeBack Mobility" Smart Crutch Tips for Mechanical Stimulation of Tibial Shaft Fracture Healing.
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.
Read more
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.
Read the 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
- Being tested
- Smart Crutch Tips™, Finite Element Analysis (FEA), Iterative walking, Lower Limb Rehabilitation Exercise Program
- Keywords
- Tibial Fracture, Fracture Healing, Intramedullary Fixation, Controlled Mechanical Loading, Weight-Bearing, Finite Element Analysis, Digital Rehabilitation, Smart Crutch Tips, Bone Union, Rehabilitation Monitoring, Lower Limb Fractures, Biofeedback Device
- Medical subject headings
- Tibial Fractures
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Smart Crutch Tips™Device
Also called ComeBack Mobility Smart Crutch Tips, Smart Crutches,, CBM Smart 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.
Finite Element Analysis (FEA)Procedure or surgery
Also called FE Modeling, Biomechanical Modeling, Postoperative Structural Simulation
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
Iterative walkingBehavioural
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™.
Lower Limb Rehabilitation Exercise ProgramProcedure or surgery
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.
| Study group | Role | What they receive |
|---|---|---|
| Control Group (Standard of Care) | No intervention | Participants will follow the standard-of-care postoperative weight-bearing protocol according to AO Foundation clinical guidelines: "Partial weight-bearing with crutches is started as soon as the patient is able. Unrestricted weight bearing should be delayed until fracture callus is visible, fibular healing is evident, and weight bearing is without pain. Depending on the consolidation, weight bearing can usually be increased after 6-8 weeks, with full weight-bearing when the fracture has healed." Smart Crutch Tips™ will be used in passive mode, with all notifications (audio and visual) disabled. Participants will not have access to any feedback regarding their weight-bearing. The devices will serve solely for data collection purposes, recording step count and applied loading during ambulation. |
| Controlled Mechanical Stimulation and Activity (Optimal Interfragmentary Motion) | Experimental | Participants will receive individualized weight-bearing prescriptions derived from finite element analysis (FEA) of their postoperative CT scan, targeting optimal interfragmentary motion at the fracture site.
Smart Crutch Tips™ will provide real-time audio and visual feedback to support adherence to the prescribed loading and activity program. Receives: Device: Smart Crutch Tips™; Procedure: Finite Element Analysis (FEA); Behavioral: Iterative walking; Procedure: Lower Limb Rehabilitation Exercise Program |
| Controlled Mechanical Stimulation and Activity According to the Claes-Heigele Theory | Experimental | Participants will receive individualized weight-bearing prescriptions derived from finite element analysis (FEA) of their postoperative CT scan, aimed at achieving the highest percentage of voxels in the fracture zone in accordance with the theory of L.E. Claes and C.A. Heigele (1999).
Smart Crutch Tips™ will provide real-time audio and visual feedback to support adherence to the prescribed loading and activity program. Receives: Device: Smart Crutch Tips™; Procedure: Finite Element Analysis (FEA); Behavioral: Iterative walking; Procedure: Lower Limb Rehabilitation Exercise Program |
What is being measured
The primary outcome is the main question the study is designed to answer.
Time to Radiographic Fracture Union
X-rays will be performed at Visit 1, Visit 2, Visit 3, Visit 4, Visit 5 and Visit 6 postoperatively. CT will be conducted at Visit 0, Visit 1, Visit 2, and optionally at Visit 3 to assess fracture union progression and load adaptation.
Fracture Consolidation Assessment Procedure:
CT and X-ray data will be evaluated separately. CT criteria include qualitative parameters (fracture line presence, edge clarity, cortical bridging) and quantitative parameters (Hounsfield units at the fracture site). Radiographic assessment will follow the modified RUST scale:
Score 1 - no callus, visible line; Score 2 - callus without bridging, visible line; Score 3 - callus with bridging, visible line; Score 4 - callus with bridging, no visible line. The total score ranges from 4 to 16. Fracture is united if at least three cortices are bridged. Delayed union is defined as a visible fracture line and no callus after 3 months.
Measured: 12 - 24 weeks post-surgery ± 7 days
Secondary outcomes (6)
mRUST Score
The modified Radiographic Union Scale for Tibial fractures (mRUST) is used to assess bone healing based on radiographs of the fracture site. Four cortices are evaluated, with scores assigned according to callus formation and visibility of the fracture line. The total score ranges from 4 to 16, with higher scores indicating more advanced bone healing. mRUST scores will be compared between intervention and control groups at each follow-up visit to determine the impact of the intervention on bone healing.
Measured: at 6, 12, 16, 20, 24, and 36 weeks after surgery (+- 7 days)
Adherence to Prescribed Axial Loading
The percentage of steps taken within the prescribed range of axial loading. Higher percentages indicate better adherence to the prescribed loading regimen. This is measured through continuous monitoring using the Smart Crutch Tips™ device and analyzed at each follow-up visit (from 0 to 36 weeks).
Measured: from 0 to 36 weeks post-surgery
Lower Extremity Functional Status (LEFS)
Assessed using the Lower Extremity Functional Scale (LEFS) - a validated instrument designed to measure a patient's ability to perform everyday physical activities involving the lower limbs. The questionnaire consists of 20 items, each scored from 0 (extreme difficulty or unable to perform) to 4 (no difficulty). The total score ranges from 0 to 80, with higher scores indicating better functional status.
Measured: 0-7 days post-surgery and at 6, 12, 16, 20, 24, 36 weeks after surgery (+- 7 days)
Recording of AEs/SAEs AR/SAAR/SUSARs, including Postoperative Complications
The following types of postoperative complications will be recorded and analyzed:
residual pain; delayed union; nonunion; malunion; implant failure; need for reoperation. Assessment will be performed clinically at each visit and supplemented with radiological evaluation (X-ray and CT), according to the visit schedule.
All adverse events (AEs), serious adverse events (SAEs), adverse reactions (ARs), serious adverse reactions (SAARs), and suspected unexpected serious adverse reactions (SUSARs) identified during the study will also be recorded, described, and analyzed.
Measured: 0-7 days post-surgery and at 6, 12, 16, 20, 24, 36 weeks after surgery (+- 7 days)
Pain Level
Assessed using the Visual Analogue Scale (VAS), presented electronically as a continuous line ranging from 0 (no pain) to 10 (worst possible pain). Higher scores indicate greater pain intensity. Assessment is conducted at each follow-up visit
Measured: 0-7 days post-surgery and at 6, 12, 16, 20, 24, 36 weeks after surgery (+- 7 days)
Fear of Movement (TSK-17)
Assessed using the Tampa Scale for Kinesiophobia, 17-item version (TSK-17), which evaluates fear of physical activity due to pain or risk of re-injury. Scores range from 17 to 68, with higher scores indicating greater fear of movement. Administered electronically at each follow-up visit.
Measured: 0-7 days post-surgery and at 6, 12, 16, 20, 24, 36 weeks after surgery (+- 7 days)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Jul 2025
- Study start28 Oct 2025
- Primary completion1 Nov 2026 (estimated)
- Study completion15 Feb 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Fracture HealingStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Comeback Mobility Inc
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Vaida Glatt, PhD, Principal investigator, UT Health
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07092579
- Sponsor's protocol ID
- CBM-UA-2025/1
- Status last verified
- Apr 2026
- First submitted
- 16 Jul 2025
- Last updated
- 14 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Time to radiographic fracture union (primary endpoint) mRUST scores at predefined time points Compliance data on axial loading collected by Smart Crutch Tips™ Functional recovery outcomes (LEFS, TSK-17 questionnaire responses) Pain level assessments (VAS) Adverse event data, including AEs, SAEs, ADEs, SADEs, and device deficiencies Gait adherence metrics derived from the CBM mobile app Baseline demographic and clinical information relevant to fracture type and healing (e.g., fracture classification, BMI, CT-derived FEA data)
Study at a glance
From the registry record, last updated by the sponsor on 14 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Study of Individual Weight-bearing and Iterative Walking Using "ComeBack Mobility" Smart Crutch Tips for Mechanical Stimulation of Tibial Shaft Fracture Healing.
- ClinicalTrials.gov ID
- NCT07092579
- Acronym / sponsor ID
- CBM-UA-2025/1
- Conditions
- Fracture Healing, Tibial Fractures
- Keywords
- Tibial Fracture, Fracture Healing, Intramedullary Fixation, Controlled Mechanical Loading, Weight-Bearing, Finite Element Analysis, Digital Rehabilitation, Smart Crutch Tips
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Comeback Mobility IncIndustry (pharma, biotech, devices)
- Study start
- 28 Oct 2025 (actual)
- Primary completion
- 1 Nov 2026 (estimated)
- Study completion
- 15 Feb 2027 (estimated)
- First posted
- 30 Jul 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Control Group (Standard of Care) | No intervention | –Participants will follow the standard-of-care postoperative weight-bearing protocol according to AO Foundation clinical guidelines: "Partial weight-bearing with crutches is started as soon as the patient is able. Unrestricted weight bearing should be delayed until fracture callus is visible, fibular healing is evident, and weight bearing is without pain. Depending on the consolidation, weight bearing can usually be increased after 6-8 weeks, with full weight-bearing when the fracture has healed." Smart Crutch Tips™ will be used in passive mode, with all notifications (audio and visual) disabled. Participants will not have access to any feedback regarding their weight-bearing. The devices will serve solely for data collection purposes, recording step count and applied loading during ambulation. |
| Controlled Mechanical Stimulation and Activity (Optimal Interfragmentary Motion) | Experimental | Device: Smart Crutch Tips™, Procedure: Finite Element Analysis (FEA), Behavioral: Iterative walking, Procedure: Lower Limb Rehabilitation Exercise ProgramParticipants will receive individualized weight-bearing prescriptions derived from finite element analysis (FEA) of their postoperative CT scan, targeting optimal interfragmentary motion at the fracture site. Smart Crutch Tips™ will provide real-time audio and visual feedback to support adherence to the prescribed loading and activity program. |
| Controlled Mechanical Stimulation and Activity According to the Claes-Heigele Theory | Experimental | Device: Smart Crutch Tips™, Procedure: Finite Element Analysis (FEA), Behavioral: Iterative walking, Procedure: Lower Limb Rehabilitation Exercise ProgramParticipants will receive individualized weight-bearing prescriptions derived from finite element analysis (FEA) of their postoperative CT scan, aimed at achieving the highest percentage of voxels in the fracture zone in accordance with the theory of L.E. Claes and C.A. Heigele (1999). Smart Crutch Tips™ will provide real-time audio and visual feedback to support adherence to the prescribed loading and activity program. |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (13 listed)
- Signed informed consent was provided after being fully informed about participation in the study.
- Age: 18 to 80 years for both males and females (pre-menopausal).
- Body weight between 40 and 120 kg.
- Body Mass Index (BMI) between 18.5 and 29.9 kg/m².
- Diagnosed with a closed tibial shaft fracture (AO/OTA classification: 42-A, 42-B, or 42-C) requiring surgical treatment.
Key exclusion criteria (16 listed)
- Presence of open or high-energy fractures, multiple lower-limb fractures, or use of bone grafts.
- Fractures classified as 43-B or 43-C according to AO/OTA.
- Chronic alcoholism (defined as >14 standard drinks per week for men or >7 for women).
- Presence of metabolic disorders, including uncontrolled thyroid dysfunction, severe renal or hepatic pathology.
- Pathological fractures associated with osteoporosis, osteomyelitis, tumors, metastases, or rickets.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Smart Crutch Tips™Also: ComeBack Mobility Smart Crutch Tips, Smart Crutches,, CBM Smart TipsSmart 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. | Device | Controlled Mechanical Stimulation and Activity (Optimal Interfragmentary Motion), Controlled Mechanical Stimulation and Activity According to the Claes-Heigele Theory |
| Finite Element Analysis (FEA)Also: FE Modeling, Biomechanical Modeling, Postoperative Structural SimulationFinite 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 | Procedure or surgery | Controlled Mechanical Stimulation and Activity (Optimal Interfragmentary Motion), Controlled Mechanical Stimulation and Activity According to the Claes-Heigele Theory |
| Iterative walkingParticipants 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™. | Behavioural | Controlled Mechanical Stimulation and Activity (Optimal Interfragmentary Motion), Controlled Mechanical Stimulation and Activity According to the Claes-Heigele Theory |
| Lower Limb Rehabilitation Exercise ProgramA 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. | Procedure or surgery | Controlled Mechanical Stimulation and Activity (Optimal Interfragmentary Motion), Controlled Mechanical Stimulation and Activity According to the Claes-Heigele Theory |
Primary outcome
Time to Radiographic Fracture Union
Time frame: 12 - 24 weeks post-surgery ± 7 days
X-rays will be performed at Visit 1, Visit 2, Visit 3, Visit 4, Visit 5 and Visit 6 postoperatively. CT will be conducted at Visit 0, Visit 1, Visit 2, and optionally at Visit 3 to assess fracture union progression and load adaptation. Fracture Consolidation Assessment Procedure: CT and X-ray data will be evaluated separately. CT criteria include qualitative parameters (fracture line presence, edge clarity, cortical bridging) and quantitative parameters (Hounsfield units at the fracture site). Radiographic assessment will follow the modified RUST scale: Score 1 - no callus, visible line; Score 2 - callus without bridging, visible line; Score 3 - callus with bridging, visible line; Score 4 - callus with bridging, no visible line. The total score ranges from 4 to 16. Fracture is united if at least three cortices are bridged. Delayed union is defined as a visible fracture line and no callus after 3 months.
6 secondary outcomes
mRUST Score
Time frame: at 6, 12, 16, 20, 24, and 36 weeks after surgery (+- 7 days)
Adherence to Prescribed Axial Loading
Time frame: from 0 to 36 weeks post-surgery
Lower Extremity Functional Status (LEFS)
Time frame: 0-7 days post-surgery and at 6, 12, 16, 20, 24, 36 weeks after surgery (+- 7 days)
Recording of AEs/SAEs AR/SAAR/SUSARs, including Postoperative Complications
Time frame: 0-7 days post-surgery and at 6, 12, 16, 20, 24, 36 weeks after surgery (+- 7 days)
Pain Level
Time frame: 0-7 days post-surgery and at 6, 12, 16, 20, 24, 36 weeks after surgery (+- 7 days)
Fear of Movement (TSK-17)
Time frame: 0-7 days post-surgery and at 6, 12, 16, 20, 24, 36 weeks after surgery (+- 7 days)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Apr 2026.
- Individual participant dataSharing planned: Yes. Time to radiographic fracture union (primary endpoint) mRUST scores at predefined time points Compliance data on axial loading collected by Smart Crutch Tips™ Functional recovery outcomes (LEFS, TSK-17 questionnaire responses) Pain level assessments (VAS) Adverse event data, including AEs, SAEs, ADEs, SADEs, and device deficiencies Gait adherence metrics derived from the CBM mobile app Baseline demographic and clinical information relevant to fracture type and healing (e.g., fracture classification, BMI, CT-derived FEA data)
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Vaida Glatt, PhD principal investigator
UT Health
18 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Smart Crutch Tips™, Finite Element Analysis (FEA) and Iterative walking in people with Fracture Healing and Tibial Fractures, run by Comeback Mobility Inc at 18 sites in Ukraine.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 13 inclusion and 16 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 14 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 18 sites in Ukraine. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Nataliia Popova (+380979137440, nap@comebackmobility.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Time to Radiographic Fracture Union (time frame: 12 - 24 weeks post-surgery ± 7 days). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Apr 2026.