Biofeedback weight-bearing devices & individual weight-bearing protocols

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

ClinicalTrials.gov | NCT07092579

 

Smart Crutch Tips for Guided Weight-Bearing in Patients Recovering From Extra-Articular Proximal Tibia Fractures

ClinicalTrials.gov | NCT07134257

 

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

 

ClinicalTrials.gov | NCT07138066

   

“Smart Crutch” Real Time Feedback Aids in Partial Weight-Bearing Adherence Following Lower Extremity Fracture: A Pilot Study

https://docs.google.com/document/d/1ws2JMgMo_Tcaceg1YNZ89r5_8mwm7_1C/edit?tab=t.0

Abstract

Purpose:

To evaluate the effectiveness of immediate weight bearing feedback crutch tips, or so called “smart crutches” in assessing and promoting patient adherence to partial weight-bearing (PWB) protocols and to explore patient experiences with a device that provided real time feedback about weight bearing.

Methods:

Twenty patients with lower extremity fractures who were allowed PWB utilizing real-time feedback crutch tips (RFC) were randomized into one of two groups: The feedback group used RFC (ComeBack Mobility, Kiev Ukraine), which provided real-time feedback on PWB compliance. The Control group also used RFC’s without real-time patient feedback. PWB compliance was defined as maintaining weight-bearing within ±10% of the prescribed range and was calculated as the percentage of steps meeting that threshold. Secondary outcomes included device usability and patient satisfaction, both assessed during the home rehabilitation period. Usability was measured via the System Usability Scale (SUS).

Results:

The Intervention group demonstrated significantly higher PWB compliance than the Control group (73.60% vs. 21.10%, p < 0.01). The Intervention group reported an average SUS score of 84.25, indicating excellent usability. There were no complications or safety events related to the use of the devices. Patient satisfaction was evaluated through video interviews: patients interviewed in the Intervention group expressed high satisfaction and a strong willingness (10/10) to recommend the device for similar injuries.

Conclusion:

RFCs were safe and effectively improved partial weight-bearing compliance during home rehabilitation. These findings support integrating such devices into wider clinical care to enhance patient outcomes and adherence to prescribed weight-bearing protocols.

Validation Testing of a New Crutch Tip Biofeedback Device for Prescribed Lower Extremity Weight-Bearing

Journal of Acute Care Physical Therapy

Abstract

Introduction:

Modified weight-bearing recommendations are commonly prescribed after surgical intervention for injuries to the lower extremity to reduce the risk of nonunion and delayed healing associated with load bearing through the injured limb and to combat the deleterious effects of immobility. The physical therapist (PT) in the acute care setting is likely to instruct patients after lower extremity injury in weight-bearing-restricted ambulation. A new device is now available for use in the training of weight-bearing status. The study examines whether the ComeBack Mobility crutch tip reporting weight-bearing on the lower extremity is a reliable and valid tool in determining force when compared with the gold standard force plate measurement of lower extremity weight-bearing.

Review of Literature:

Previous studies have shown that patients are often not able to adequately learn or adhere to restrictive weight-bearing modifications. This may be due to an inability to provide immediate and ongoing feedback on weight-bearing. The new ComeBack Mobility crutch tip system is now available for the acute care PT to use in instruction and for patients to receive real-time feedback throughout their rehabilitation process.

Subjects:

A sample of convenience of 6 able-bodied PTs was used.

Methods:

Each subject performed 30 trials of axillary crutch-assisted weight-bearing ambulation using the new device. The weight-bearing reported by the device was compared with the weight-bearing measured through force plates via correlations, t tests, and Bland-Altman plot.

Results:

The new device demonstrated moderate-good reliability in the measurement of non-weight-bearing and 50% partial weight-bearing in trials completed.

Discussion and Conclusion:

The ComeBack Mobility crutch tip system could be useful and should be considered for clinical use as a reliable and valid tool in providing auditory feedback for compliance to a prescribed weight-bearing protocol. The system could be useful in the training of patients in the first use of crutches such as prior to discharge from an acute care hospital. Further research is needed with clinical populations as well as with varied weight-bearing protocols.

Early Fracture Activity is Crucial for Bone Regeneration

The relation between fracture activity and bone healing with special reference to the early healing phase – A preclinical study – Injury

Abstract

Background

Fracture healing outcome is to a great extent steered by the mechanical environment. The importance of early phase mechanical fracture stimulation is still controversially discussed, both clinically and scientifically. Furthermore, the role of fracture activity, defined as the number of stimulatory events per time, is particularly for the direct postoperative phase unknown.

Methods

Tibial defects of seven Swiss mountain sheep were stabilized with a dynamizable bone fixator, which allowed for defined interfragmentary motion by limiting the maximum axial displacement. The fixator was further equipped with a telemetric measuring unit to continuously log all occurring displacement events above a predefined amplitude threshold over an 8-weeks observation period. Callus size was measured over time from X-rays. Ultimate torsional strength of the healed defects was assessed after euthanasia.

Results

One animal had to be excluded from the experiment due to technical reasons. The remaining six animals exhibited consistently the highest fracture activity in week 1 post-operation with 6′029 displacement events per week for the animal with the lowest activity and 21′866 events per week for the most active animal. Afterwards fracture activity gradually decreased over time. Strong and significant correlations were found for fracture activity in week 1 and 2 with torsional strength of the healed bone (R ≥ 0.881, p ≤ 0.02). No significant correlations were observed at later timepoints. Fracture activity in week 1 and 2 also correlated strongly with the maximum callus area as measured from X-rays (R ≥ 0.846, p ≤ 0.034).

Conclusions

The data demonstrates a positive effect of, within limits, frequent fracture stimulation on bone healing and suggests the importance of the mechanical environment in the direct post-operative healing phase. Clinically, the findings may advocate for the concept of direct post-operative weight bearing. This, however, requires clinical validation and must be considered within the full clinical context including the risk for fixation failure from overloading.

Keywords

1. Bone
2. Fracture healing
3. Mechanobiology
4. Early weight bearing
5. Fracture activity

Reverse Dynamisation Boosts Healing by Controlling Strain

Glatt

Abstract The present review acknowledges the tremendous impact of Stephan Perren’s strain theory, considered with respect to the earlier contributions of Roux and Pauwels. Then, it provides further insight by examining how the concept of reverse dynamisation extended Perren’s theory within a modern context. A key factor of this more contemporary theory is that it introduces variable mechanical conditions at different time points during bone healing, opening the possibility of manipulating biology through mechanics to achieve the desired clinical outcome. The discussion focusses on the current state of the art and the most recent advances made towards and accelerating bone regeneration, by actively controlling the mechanical environment as healing progresses. Reverse dynamisation utilises a very specific mechanical manipulation regimen, with conditions initially flexible to encourage and expedite early callus formation. Once callus has formed, the mechanical conditions are intentionally modified to create a rigid environment under which the soft callus is quickly converted to hard callus, bridging the fracture site and leading to a more rapid union. The relevant literature, principally animal studies, was surveyed to provide ample evidence in support of the effectiveness of reverse dynamisation. By providing a modern perspective on Stephan Perren’s strain theory, reverse dynamisation perhaps holds the key to tipping the balance in favour of a more rapid and reliable union when treating acute fractures, osteotomies, non-unions and other circumstances where it is necessary to regenerate bone.

Keywords: Reverse dynamisation, dynamisation, interfragmentary strain theory, bone healing, fracture healing, mechanical environment, fixation stability, animal models.

Address for correspondence: Vaida Glatt, PhD, Assistant Professor, Department of Orthopedic Surgery, University of Texas Health Science Centre San Antonio, 7703 Floyd Curl Drive, MC 7774, San Antonio, TX 78229-3900, USA.

Telephone number: +1 2104508094 Email: glatt@uthscsa.edu

Copyright policy: This article is distributed in accordance with Creative Commons Attribution Licence (http://creativecommons.org/licenses/by-sa/4.0/).

Magnitudes of local stress & strain along bony surfaces

Predict the course & type of fracture healing!

PII: S0021-9290(98)00153-5

Abstract A new quantitative tissue di¤erentiation theory which relates the local tissue formation in a fracture gap to the local stress and strain is presented. Our hypothesisproposes that the amounts ofstrain and hydrostaticpressure along existing calciÞedsurfaces in the fracture callus determine the di¤erentiation of the callus tissue. The study compares the local strains and stresses in the callus as calculated from a Þnite element model with histological Þndings from an animal fracture model. The hypothesis predicts intramem branousboneformationforstrains smallerapproximately$5%andhydrostaticpressuressmaller than $0.15 MPa.Endochondral ossiÞcation is associated with compressive pressures larger than about !0.15 MPa and strains smaller than $15%. All other conditions seemed to lead to connective tissue or Þbrous cartilage. The hypothesis enables a better understanding of the complex tissue di¤erentiation seen in histological images and the mechanical conditions for healing delayed healing or nonunions. ( 1999 Elsevier Science Ltd. All rights reserved.

Keywords: Bone healing; Mechanical stimuli; Tissue di¤erentiation

Applying Right Amount Of Strain Improves Healing! 

If strain goes beyond certain limits – it slows down the healing process!

Controlled Mechanical Stimulation in the Treatment of Tibia1 Fractures.pdf – Google Диск

Abstract Although it is known that the mechanical environment affects the fracture healing process, the optimal conditions for the different stages of healing have not been defined. In the present studies, the influence of applying a very short period of axial micromovement with defined characteristics to healing fractures has been studied both in simulated and clinical tibial fractures. The fracture healing process is seen to be acutely sensitive to small periods of daily strain applied axially within two weeks of fracture. There are boundaries of strain magnitude and force of application of applied movement that, if exceeded, inhibit the healing process. The application of appropriate applied strain to clinical tibial fractures at a time shortly after injury, when most patients would be very inactive, appears to enhance the healing process when using external skeletal fixation.

Individualized Determination of the Mechanical Fracture Environment After Tibial Exchange Nailing—A Simulation-Based Feasibility Study

Frontiers | Individualized Determination of the Mechanical Fracture Environment After Tibial Exchange Nailing—A Simulation-Based Feasibility Study