Optimizing Prosthetic and Bicycle Fit for Veterans With Transtibial Amputations

NCT03828331 | Completed Results

• 1 other identifier: A3010-P
• Study Type: observational
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

Bicycling is a promising form of low-impact exercise that could prevent/treat Type 2 diabetes. However, Veterans with transtibial amputations (TTAs) may not effectively utilize bicycling for rehabilitation and exercise due to improper bike fit, socket discomfort, and/or the potential for injury. An optimized prosthetic/bicycle fit could improve comfort and reduce injury risk by decreasing asymmetries between legs, lowering metabolic costs, and improving efficiency for Veterans with TTAs during bicycling. Moreover, the use of objective prosthetic/bicycle fit guidelines would allow clinicians to facilitate shorter appointment times and fewer revisits for Veterans with TTAs. The investigators will determine the physiological and biomechanical effects of different prosthetic and bicycle configurations for Veterans with a TTA to develop optimal prosthetic/bicycle fit guidelines. The investigators hypothesize that a longer prosthetic pylon length and shorter bicycle crank arm length for the affected compared to the unaffected leg along with a pedal attachment position beneath the pylon compared to beneath the forefoot will optimize performance for Veterans with TTAs the investigators' research will integrate evidence-based guidelines to advance rehabilitation and enhance the lives of Veterans with an amputation, thus improving and restoring their function.

Conditions

Amputation

Keywords

Rehabilitation

Outcome Measures

Primary Outcomes (4)

• Mechanical Crank Power Output

  The investigators calculated crank power output (W/kg) from the product of pedal torque and velocity and normalized this to participant body mass while participants rode at 1.5 W/kg using different prosthetic and bicycle configurations (pylon length, crank arm length, and pedal attachment position).

  Data were collected over 2 days per subject

• Net Metabolic Power

  The investigators measured net metabolic power (W/kg) using an equation that considers rates of oxygen consumption and carbon dioxide production and normalized this to participant body mass while participants rode at 1.5 W/kg using different prosthetic and bicycle configurations (pylon length, crank arm length, and pedal attachment position).

  Data were collected over 2 days per subject

• Perceived Comfort (Visual Analog Scale (VAS))

  The investigators measured comfort with a questionnaire that has a range of 0-10 that indicates terrible to excellent, respectively, after participants rode at 1.5 W/kg using different prosthetic and bicycle configurations (pylon length, crank arm length, and pedal attachment position).

  Data were collected over 2 days per subject

• Perceived Satisfaction (Prosthesis Evaluation Questionnaire (PEQ))

  The investigators measured satisfaction with a questionnaire that has a range of 0-10 that indicates extremely dissatisfied to extremely satisfied, respectively, after participants rode at 1.5 W/kg using different prosthetic and bicycle configurations (pylon length, crank arm length, and pedal attachment position).

  Data were collected over 2 days per subject

Study Arms (1)

Participants with Transtibial Amputation

The investigators will recruit participants with unilateral transtibial amputations who are at or above a K3 Medicare functional classification level (MFCL), and 18-55 years old. A K3 MFCL means that a person has the ability or potential for ambulation with variable cadence. A person at K3 MFCL is a typical community ambulator who has the ability to traverse most environmental barriers and may have vocational, therapeutic or exercise activity that demands prosthetic use beyond simple locomotion.

Other: Prosthetic/Bicycle Configuration

Interventions

Prosthetic/Bicycle Configuration OTHER

The investigators will measure the biomechanics (motion, forces, and muscle activity) and metabolic rates while subjects ride using an initial bike fit and three taller pylon lengths (PL) for the affected leg (AL) in increments of 6.8 mm using a pedal attachment position (PAP) beneath the prosthetic forefoot. Then, using the optimal (most efficient) PL, the investigators will measure the biomechanics and metabolic rates while subjects ride using three shorter crank arm lengths (CALs) for the AL in decrements of 6.8 mm using a PAP beneath the prosthetic forefoot. On Day 2, the investigators will repeat the protocol of Day 1, but have riders use a PAP beneath the pylon for their AL.

Participants with Transtibial Amputation

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

The investigators will recruit 15 subjects with unilateral transtibial amputations from the VA Jewell Clinic, locally, and nationally.

You may qualify if:

• One amputation below the knee
• At least 1 year of experience using a prosthesis
• No current problems with the prosthesis or residual limb
• At or above a K3 Medicare Functional Classification Level

You may not qualify if:

• Poor general health
• Difficulty with mobility
• Problems with balance or dizziness
• Current serious musculoskeletal injury besides that associated with an amputation
• Cardiovascular, pulmonary, or neurological disease or disorder

Sponsors & Collaborators

• VA Office of Research and Development: lead

Study Sites (1)

Rocky Mountain Regional VA Medical Center, Aurora, CO

Aurora, Colorado, 80045, United States

Location

Related Publications (1)

• Allen SP, Diaz GB, Grabowski AM. The Effect of Unequal Crank Arm Lengths and Cycling-Specific Prostheses for Recreational Riders with a Transtibial Amputation. Med Sci Sports Exerc. 2024 Oct 1;56(10):1976-1987. doi: 10.1249/MSS.0000000000003480. Epub 2024 May 15.

  PMID: 38768009 RESULT

Results Point of Contact

• Title: Dr. Alena Grabowski
• Organization: VA Eastern Colorado Healthcare System

alena.grabowski@va.gov

303-492-5208

Study Officials

• Alena Grabowski, PhD BA

  Rocky Mountain Regional VA Medical Center, Aurora, CO

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: FED
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 22, 2019
• First Posted: February 4, 2019
• Study Start: April 1, 2019
• Primary Completion: August 31, 2023
• Study Completion: August 31, 2023
• Last Updated: December 10, 2024
• Results First Posted: December 10, 2024

Record last verified: 2024-12

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)