Assessment of Strength, Balance, and Function in Above-Knee Amputees in Relation to Residual Limb Length

NCT07032233 | Not Yet Recruiting DMC

• 1 other identifier: FTREK25/31
• Study Type: observational
• Target: 15
• Locations: 0 countries
• Sites: N/A

Brief Summary

The goal of this observational study is to learn how muscle strength, balance, and functional ability are affected in people with above-knee (transfemoral) amputations. The main questions it aims to answer are: How does the length of the lost part of the leg, compared to the intact leg, affect muscle strength, balance, and functional capacity? Is muscle strength at specific lower limb joints related to balance and performance ? Participants will: Have muscle strength measured at all intact lower limb joints using an isokinetic dynamometer Complete balance assessments using force platform technology that measures weight distribution and evaluates both static and dynamic balance Perform a six-minute walk test to evaluate endurance and functional capacity The study will help improve understanding of how limb length and joint-specific muscle strength impact mobility, supporting the development of better rehabilitation programs for amputees.

Conditions

Transfemoral Amputation

Keywords

Transfemoral Amputation; Muscle Strength; Isokinetic Dynamometry; Balance Assessment; Functional Capacity; Residual Limb Length; Prosthetics; Postural Control; Gait; Six-Minute Walk Test; Mobility

Outcome Measures

Primary Outcomes (4)

• Length of Residual Limb and Intact Limb (cm) and Percentage of Limb Loss (%)

  Anthropometric measurements will be performed using a standard measuring tape. For the amputated limb, the distance will be measured from the greater trochanter to the distal end of the residual limb along the lateral midline. For the intact limb, the measurement will extend from the greater trochanter to the plantar surface of the foot. The difference between these two measurements will represent the length of the lost limb. The percentage of limb loss will then be calculated by comparing the lost length to the total length of the intact limb.

  1 day

• Isokinetic Strength Testing

  Isokinetic muscle strength assessments will be conducted using the IsoMed 2000 Dynamometer (D\&R Ferstl GmbH, Hemau, Germany). Measurements will include peak torque (Nm) and total work (J) values for hip, knee, and ankle flexor/extensor muscles. Testing will be performed under the following angular velocities and repetitions: 1. Hip Flexion/Extension: 5 reps at 60°/s, 10 reps at 120°/s (supine position) 2. Knee Flexion/Extension: 5 reps at 60°/s, 10 reps at 180°/s (seated, hip at 90°) 3. Ankle Plantar/Dorsiflexion: 5 reps at 60°/s, 10 reps at 120°/s (seated, semi-flexed hip, 90° knee flexion) Rest periods will be given between measurements to minimize fatigue. Tests will be randomized across different joints and days to avoid order effects. Data will be summarized as peak torque and total work values for each muscle group at the specified angular velocities.

  5 days

• Stability Coefficient (Eyes Open and Closed), Single-Leg Stability of Intact Side, and Limits of Stability (mm)

  Participants' balance abilities will be assessed using the Huber 360® Evolution (LPG Systems, Valence, France), a motorized multi-axial platform with integrated force sensors. The following parameters will be measured and reported: 1. Static balance with eyes open and eyes closed (coefficient of stability) 2. Single-Leg Stability on the intact limb (coefficient of stability) 3. Limits of stability quantified as sway in mm

  1 day

• 6 minute walk test

  1 day

Secondary Outcomes (2)

• The Amputee Mobility Predictor (AMP)

  1 day

• The Comprehensive Lower-limb Amputee Socket Survey (CLASS)

  1 day

Other Outcomes (1)

• Information regarding amputation history and prosthesis use and demographics

  1 day

Study Arms (1)

transfemoral amputation

Adults with unilateral transfemoral amputation who indepently ambulates with a prosthetic limb.

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Participants will be selected from the population of adults with unilateral transfemoral amputation who are able to ambulate independently with a prosthesis. The target population includes individuals between the ages of 18 and 50 who have been using a prosthesis for at least 6 months. Eligible participants must be literate and free from cardiovascular, orthopedic, cognitive, or neurological conditions that could interfere with gait, balance, or muscle strength. Recruitment may occur through rehabilitation clinics, prosthetics centers, or community referrals.

You may qualify if:

• Individuals will be included in the study if they:
• Are between 18 and 50 years of age
• Are literate
• Have unilateral transfemoral amputation
• Have no cardiovascular, orthopedic, cognitive, or neurological conditions that could negatively affect balance, gait, or muscle strength
• Are able to ambulate independently with a prosthesis
• Have been walking for at least 6 months
• Voluntarily agree to participate in the study

You may not qualify if:

• Participants will be excluded from the study if:
• They develop complications such as pain (rated 3 or higher on the Visual Analog Scale) or stump irritation during the course of the study
• Their residual limb length is less than 25 cm from the greater trochanter, which exceeds the limitations of the isokinetic dynamometer attachments used in the study
• They voluntarily withdraw from the study - in such cases, their data will be removed from the records

Sponsors & Collaborators

• Ceren Kuzu: lead
• Gaziler Physical Medicine and Rehabilitation Education and Research Hospital: collaborator
• Hacettepe University: collaborator

Central Study Contacts

Ceren Kuzu, MSc, Physical Therapist

CONTACT

+905067027093; ce.kuzu@gmail.com

Semra Topuz, Prof, Physical Therapist

CONTACT

+905055800590; fztsemra@yahoo.com

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: CROSS SECTIONAL
• Target Duration: 5 Days
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: PhD Candidate, Physiotherapist

Study Record Dates

• First Submitted: June 6, 2025
• First Posted: June 22, 2025
• Study Start: June 1, 2025
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): September 1, 2026
• Last Updated: June 22, 2025

Record last verified: 2025-06