Hamstring Muscle StrainNCT07870408
Correlation Between Soft Tissue Displacement and Functional Performance in Orthopedic Patients
A study testing Nordic Hamstring Exercise Training, Custom Foot Orthoses and Exercise Therapy and Forearm Blood Flow Restriction Training in people with Hamstring Muscle Strain and Adult Acquired Flatfoot Deformity, run by National Taiwan University Hospital at 1 site in Taiwan.
Trial summary
The goal of this clinical trial is to investigate the correlations between dynamic soft tissue displacement, mechanical properties, and functional recovery across three studies: biceps femoris long head (BFlh) muscle injury, adult acquired flatfoot deformity (AAFD), and medial ulnar collateral ligament anterior bundle… Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- Hamstring Muscle Strain, Adult Acquired Flatfoot Deformity, Ulnar Collateral Ligament Sprain After Reconstruction
- What is being tested?
- Nordic Hamstring Exercise Training, Custom Foot Orthoses and Exercise Therapy and Forearm Blood Flow Restriction Training
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 80 participants
- Where
- 1 siteTaiwan
- Study dates
- Nov 2026to Jul 2028
- 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
- Aged between 18 and 40 years
- Participated in regular physical exercise for at least 2.5 hours per week
- Experimental group: Sustained a unilateral hamstring muscle injury diagnosed as a muscle strain within the past 6 months, have returned to the team, but currently remain unable to fully participate in training or competition at maximal intensity
- Control group: Sustained a unilateral hamstring muscle injury within the past 6 months, have achieved full return to sport, and are fully able to participate in maximal-intensity training and competition
- Palpation assessment confirms tenderness isolated to the unilateral biceps femoris long head
- Aged between 18 and 80 years
Show all 11Show fewer
- Diagnosed with functional or flexible flatfoot and recommended for conservative treatment by a physician
- Six-Item Foot Posture Index (FPI-6) score >= 6, or a navicular drop test (NDT) > 9 mm.
- Overhead throwing athletes aged between 18 and 35 years
- History of unilateral anterior bundle medial ulnar collateral ligament (mUCLAB) reconstruction
- Have returned to sports training and competition following reconstruction surgery
Who cannot join
- Palpable distinct defect or gap within the injured biceps femoris long head resembling a severe (grade III) muscle tear
- Known systemic diseases that may alter soft tissue composition and mechanical properties
- Other musculoskeletal injuries of the lower extremity within the past 6 months (e.g., fractures)
- History of surgery in the lower extremities
- Any lower extremity orthopedic conditions (e.g., knee osteoarthritis, patellofemoral pain)
- Part 2
Show all 17Show fewer
- Recommended by a physician to undergo surgical treatment
- Structural or rigid flatfoot
- Posterior tibial tendon rupture or tendinopathy (including acute tenosynovitis or chronic tendinosis)
- Presence of chronic ankle instability, or residual symptoms resulting from traumatic foot ligament tear
- Other lower-extremity neuromusculoskeletal disorders, trauma with residual symptoms, or history of surgical intervention
- Any physical condition that could interfere with the study procedures
- Part 3
- Known systemic diseases that alter soft tissue composition and mechanical properties (e.g., ankylosing spondylitis, rheumatoid arthritis, amyloidosis, type 1 diabetes)
- History of two or more mUCLAB reconstruction surgeries (revision reconstructions)
- History of central or peripheral cardiovascular diseases
- Any other physical condition that interferes with daily sports training and competition
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Taiwan1 site
School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University
Taipei City, Taipei, 10055
Hsing-Kuo Wang, DPT, PhD, +886-2-33668154, hkwang@ntu.edu.tw
About this study
Official title: Correlation Between Soft Tissue Displacement and Functional Performance in Orthopedic Patients: Muscle Injury, Tendon Dysfunction, and Ligament Reconstruction
The goal of this clinical trial is to investigate the correlations between dynamic soft tissue displacement, mechanical properties, and functional recovery across three studies: biceps femoris long head (BFlh) muscle injury, adult acquired flatfoot deformity (AAFD), and medial ulnar collateral ligament anterior bundle (mUCLAB) reconstruction. The main questions it aims to answer are:
- In athletes with BFlh injury who have returned to sport but remain limited in full participation, does an 8-week Nordic hamstring exercise (NHE) program alter BFlh displacement measured by ultrasound speckle tracking (UST) during maximal eccentric testing and improve eccentric strength?
- In adults with flexible AAFD/PCFD, does a 6-week intervention of conservative exercise and custom foot orthoses alter the dynamic mechanical behavior (longitudinal displacement and dynamic torsion tracked by UST) and mechanical properties (shear wave elastography, SWE) of the posterior tibial tendon (PTT)?
- In overhead athletes after mUCLAB reconstruction, does an 8-week blood flow restriction (BFR) training program targeting the forearm flexor-pronator mass reduce regional strain quantified by UST and alter the Young's modulus of the reconstructed graft under dynamic valgus stress?
Read more
Researchers will compare biomechanical and functional outcomes within participants before and after each intervention, as well as against comparison groups (athletes with full return-to-sport clearance or asymptomatic flatfoot adults), using UST algorithms and SWE. Depending on their allocated cohort, participants will:
Part 1 (Hamstring Muscle Injury):
- Perform an 8-week progressive Nordic hamstring exercise (NHE) program (for the experimental group)
- Undergo BFlh muscle stiffness assessment using SWE and power Doppler examination for intramuscular scar vascularity
- Complete pain-free maximal isokinetic eccentric knee flexion tests and isometric contractions combined with UST and surface electromyography (sEMG) to measure muscle displacement, scar gap size, and peak torque
- Complete hamstring flexibility testing (active knee extension test) and fill out the Functional Assessment Scale for Acute Hamstring Injuries (FASH)
Part 2 (Adult Acquired Flatfoot Deformity):
- Receive 6 weeks of conservative intervention consisting of wearing custom-molded foot orthoses (for at least 85% of days) combined with progressive PTT eccentric training, short-foot exercises, and calf stretches
- Undergo SWE to evaluate proximal and distal PTT shear wave velocity. Perform progressive isometric foot adduction on an isokinetic dynamometer with UST recording raw radiofrequency (RF) data to measure PTT longitudinal displacement and cross-sectional dynamic torsion
- Complete clinical assessments at baseline, 6 weeks, and 12-week follow-up, including single-leg heel-rise tests, isokinetic strength, ankle range of motion, force-plate balance tests, 5-minute walk tests, and self-reported questionnaires (FFI-R, MSK-HQ)
Part 3 (Elbow Ligament Reconstruction Cohort):
- Participate in an 8-week progressive isokinetic strength training program for the forearm flexor-pronator mass combined with blood flow restriction, alongside grip training
- Undergo dynamic elbow valgus stress testing at 5 N·m torque on an isokinetic dynamometer synchronized with UST and SWE to evaluate regional strain and Young's modulus of the reconstructed mUCLAB
- Complete upper-extremity evaluations before and after training, including shoulder-elbow range of motion, isometric muscle strength using hand-held dynamometry, countermovement push-up (CMPU) power tests on force plates, and the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire
- Conditions
- Hamstring Muscle Strain, Adult Acquired Flatfoot Deformity, Ulnar Collateral Ligament Sprain After Reconstruction
- Being tested
- Nordic Hamstring Exercise Training, Custom Foot Orthoses and Exercise Therapy, Forearm Blood Flow Restriction Training
- Keywords
- Soft tissue, Rehabilitation, Physical therapy, Ultrasound speckle tracking
- Medical subject headings
- Flatfoot
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Nordic Hamstring Exercise TrainingBehavioural
An 8-week progressive Nordic hamstring curl exercise protocol performed twice weekly. Following initial technique instruction, participants perform progressive eccentric hamstring curls starting from 3 sets of 6 repetitions in weeks 1-2 and progressing to 3 sets of 12 repetitions in weeks 7-8.
Custom Foot Orthoses and Exercise TherapyBehavioural
A 6-week conservative program consisting of: (1) Wearing custom-molded foot orthoses daily during ambulatory activities; (2) Progressive eccentric posterior tibial tendon strengthening on an isokinetic dynamometer (twice a week, 3 sets of 15 repetitions); (3) Progressive short-foot exercises (30-40 repetitions daily); and (4) Gastrocnemius and soleus stretching.
Forearm Blood Flow Restriction TrainingOther
An 8-week progressive isokinetic strength training program targeting the forearm flexor-pronator muscles (pronator teres, flexor carpi ulnaris, brachialis) and handgrip, performed twice weekly. Exercises are performed under pneumatic blood flow restriction set at 70% limb occlusion pressure (LOP) of the brachial artery, at 40-60% of maximal voluntary isometric contraction (4 sets of 20 repetitions per muscle group).
| Study group | Role | What they receive |
|---|---|---|
| Athletes with BFlh Strain with Limited Return | Experimental | Athletes within 6 months of a unilateral biceps femoris long head (BFlh) muscle injury who have returned to the team but cannot fully participate in high-intensity training or competition. Participants complete an 8-week progressive Nordic hamstring exercise program (twice weekly, progressing from 3 sets of 6 to 3 sets of 12 repetitions) to evaluate changes in muscle displacement and eccentric knee flexor strength. Receives: Behavioral: Nordic Hamstring Exercise Training |
| Adults with Symptomatic Adult Acquired Flatfoot Deformity | Experimental | Adults aged 18-80 years diagnosed with symptomatic flexible flatfoot (FPI-6 score >= 6 or navicular drop > 9 mm). Participants undergo 6 weeks of conservative therapy consisting of daily custom foot orthoses, progressive posterior tibial tendon eccentric training (twice weekly), daily short-foot exercises, and calf stretching, followed by evaluation at baseline, week 6, and week 12 follow-up. Receives: Behavioral: Custom Foot Orthoses and Exercise Therapy |
| Overhead Athletes with Post-mUCL Reconstruction | Experimental | Overhead athletes aged 18-35 years who have undergone unilateral medial ulnar collateral ligament anterior bundle (mUCLAB) reconstruction and returned to training or competition. Participants complete an 8-week progressive isokinetic strength training program targeting the forearm flexor-pronator mass under blood flow restriction twice weekly. Receives: Other: Forearm Blood Flow Restriction Training |
What is being measured
The primary outcome is the main question the study is designed to answer.
Longitudinal Muscle Displacement of the Biceps Femoris Long Head (Arm 1)
Longitudinal muscle displacement in millimeters of the middle biceps femoris long head (BFlh) tracked using ultrasound speckle tracking during a 20°/s maximal pain-free isokinetic eccentric knee flexion task.
Measured: Baseline and Week 8 post-intervention
Posterior Tibial Tendon Dynamic Torsion, Tendon Displacement, and Shear Wave Velocity (Arm 2)
PTT dynamic torsion and displacement quantified using cross-sectional ultrasound speckle tracking during maximal isometric foot adduction, and tendon mechanical properties evaluated as mean shear wave velocity using shear wave elastography at proximal and distal tibialis posterior tendon.
Measured: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Regional Strain of the Reconstructed mUCLAB Graft (Arm 3)
Regional engineering strain along the longitudinal axis of the reconstructed medial ulnar collateral ligament anterior bundle (mUCLAB) across proximal, middle, and distal regions, quantified using ultrasound speckle tracking under a standardized 5 N·m dynamic valgus torque.
Measured: Baseline and Week 8 post-intervention
Secondary outcomes (18)
Eccentric Knee Flexor Peak Torque (Arm 1)
Maximal eccentric knee flexor peak torque (N·m) evaluated at 20°/s isokinetic velocity using an isokinetic dynamometer (Biodex Medical Systems, NY, USA) across a range of 90° to 0° knee flexion.
Measured: Baseline and Week 8 post-intervention
Functional Assessment Scale for Acute Hamstring Injuries (FASH) Score (Arm 1)
Self-reported hamstring injury symptoms and physical function assessed using the FASH questionnaire. The score ranges from 0 to 100, where higher scores indicate superior hamstring function and less severity of symptoms.
Measured: Baseline and Week 8 post-intervention
Long Head of Biceps Femoris Muscle Shear Wave Velocity (Arm 1)
Resting muscle stiffness quantified as shear wave velocity (m/s) at the suspected BFlh injury site and adjacent regions (1 cm proximal and distal) using shear wave elastography with a curved transducer.
Measured: Baseline and Week 8 post-intervention
Intramuscular Power Doppler Vascularity Grade (Arm 1)
Vascularity around the suspected BFlh injury site evaluated using power Doppler ultrasonography on a 4-point ordinal scale: Grade 0 (no flow or 1 color pixel), Grade 1 (2-3 color pixels or 1 vessel), Grade 2 (2-3 vessels), and Grade 3 (>3 vessels).
Measured: Baseline and Week 8 post-intervention
Intramuscular Scar Gap Size During Isometric Contraction (Arm 1)
Measurement of the presence and gap size (mm) around the intramuscular scar tissue visualized in the longitudinal view under dynamic B-mode ultrasound during maximal voluntary isometric knee flexion at 30°.
Measured: Baseline and Week 8 post-intervention
Hamstring Flexibility (Arm 1)
Hamstring flexibility evaluated via the active knee extension test in a supine 90-90 hip-knee position, recorded as the final achieved knee extension angle (in degrees, °) measured with a goniometer.
Measured: Baseline and Week 8 post-intervention
Revised Foot Function Index (FFI-R) (Arm 2)
Patient-reported foot symptoms, pain, disability, and activity limitation evaluated via the Revised Foot Function Index (FFI-R), scored from 0 to 100 with higher scores reflecting greater impairment.
Measured: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Musculoskeletal Health Questionnaire (MSK-HQ) Score (Arm 2)
Overall musculoskeletal health status and quality of life assessed via the MSK-HQ. The total score ranges from 0 to 56, with higher scores representing better musculoskeletal health.
Measured: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Visual Analog Scale (Arm 2)
Patient self-reported foot pain intensity measured on a 100-mm Visual Analog Scale (VAS), where 0 mm indicates no pain and 100 mm indicates worst imaginable pain.
Measured: Baseline, each treatment session before/after, Week 6, and Week 12 (follow-up)
Single-Leg Heel-Rise Test (Arm 2)
Functional performance of the posterior tibial muscle evaluated via the single-leg heel-rise test, documenting heel elevation height (cm) and the presence of heel inversion.
Measured: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Maximal Voluntary Isometric Foot Inversion Torque (Arm 2)
Maximal voluntary isometric foot inversion peak torque (N·m) measured using an isokinetic dynamometer (Biodex Medical Systems, NY, USA) with simultaneous electromyography monitoring to ensure isolation of the tibialis posterior.
Measured: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Five-Minute Walk Test (Arm 2)
Functional walking capacity evaluated as the total distance walked (in meters) within 5 minutes.
Measured: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Y-Balance Test (Arm 2)
Dynamic standing balance evaluated via the Y-balance test with the stance leg, recording foot excursion (in cm) during movement of the reach leg.
Measured: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Countermovement Push-Up (CMPU) Maximal Vertical Force (Arm 3)
Upper-extremity explosive strength and power assessed as maximal vertical ground reaction force (in Newtons) recorded on a portable force plate during the CMPU test.
Measured: Baseline and Week 8 post-intervention
Disabilities of the Arm, Shoulder, and Hand (DASH) Score (Arm 3)
Subjective upper-extremity functional recovery and disability assessed using the Taiwan version of the DASH questionnaire, scored from 0 to 100 (higher scores indicate greater disability and symptom severity).
Measured: Baseline and Week 8 post-intervention
Regional Young's Modulus of Reconstructed mUCLAB (Arm 3)
Tissue elasticity and stiffness (in kPa) of the reconstructed mUCLAB measured at the proximal, middle, and distal regions using shear wave elastography.
Measured: Baseline and Week 8 post-intervention
Shoulder and Elbow Maximal Voluntary Isometric Muscle Strength (Arm 3)
Maximal voluntary isometric contraction strength (in Newtons or kilograms) of the shoulder and elbow muscle groups measured using a hand-held dynamometer (microFET®2, Hoogan Health Industries, West Jordan, UT, USA).
Measured: Baseline and Week 8 post-intervention
Shoulder and Elbow Active Range of Motion (Arm 3)
Active range of motion (in degrees, °) of the shoulder (flexion, internal/external rotation) and elbow (flexion, extension, pronation, supination) measured using a standard universal goniometer.
Measured: Baseline and Week 8 post-intervention
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Oct 2026
- Study startNov 2026 (estimated)
- Primary completionJul 2028 (estimated)
- Study completionJul 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Hamstring Muscle StrainStudies of the same condition, open and under way.
- More trials run by National Taiwan University HospitalThe sponsor's other registered studies.
- 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
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 80 participants (estimated)
Sponsor and investigators
- Lead sponsor
- National Taiwan University Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Hsing-Kuo Wang, DPT, PhD, Study chair, School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07870408
- Sponsor's protocol ID
- 202501037RIND
- Status last verified
- Sep 2026
- First submitted
- 6 Oct 2026
- Last updated
- 21 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 21 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Correlation Between Soft Tissue Displacement and Functional Performance in Orthopedic Patients: Muscle Injury, Tendon Dysfunction, and Ligament Reconstruction
- ClinicalTrials.gov ID
- NCT07870408
- Acronym / sponsor ID
- 202501037RIND
- Conditions
- Hamstring Muscle Strain, Adult Acquired Flatfoot Deformity, Ulnar Collateral Ligament Sprain After Reconstruction
- Keywords
- Soft tissue, Rehabilitation, Physical therapy, Ultrasound speckle tracking
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 80 participants (estimated)
- Lead sponsor
- National Taiwan University HospitalUniversity, hospital or other
- Study start
- Nov 2026 (estimated)
- Primary completion
- Jul 2028 (estimated)
- Study completion
- Jul 2028 (estimated)
- First posted
- 13 Oct 2026 (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 investigate the correlations between dynamic soft tissue displacement, mechanical properties, and functional recovery across three studies: biceps femoris long head (BFlh) muscle injury, adult acquired flatfoot deformity (AAFD), and medial ulnar collateral ligament anterior bundle (mUCLAB) reconstruction. The main questions it aims to answer are:
- In athletes with BFlh injury who have returned to sport but remain limited in full participation, does an 8-week Nordic hamstring exercise (NHE) program alter BFlh displacement measured by ultrasound speckle tracking (UST) during maximal eccentric testing and improve eccentric strength?
- In adults with flexible AAFD/PCFD, does a 6-week intervention of conservative exercise and custom foot orthoses alter the dynamic mechanical behavior (longitudinal displacement and dynamic torsion tracked by UST) and mechanical properties (shear wave elastography, SWE) of the posterior tibial tendon (PTT)?
- In overhead athletes after mUCLAB reconstruction, does an 8-week blood flow restriction (BFR) training program targeting the forearm flexor-pronator mass reduce regional strain quantified by UST and alter the Young's modulus of the reconstructed graft under dynamic valgus stress?
Researchers will compare biomechanical and functional outcomes within participants before and after each intervention, as well as against comparison groups (athletes with full return-to-sport clearance or asymptomatic flatfoot adults), using UST algorithms and SWE. Depending on their allocated cohort, participants will:
Part 1 (Hamstring Muscle Injury):
- Perform an 8-week progressive Nordic hamstring exercise (NHE) program (for the experimental group)
- Undergo BFlh muscle stiffness assessment using SWE and power Doppler examination for intramuscular scar vascularity
- Complete pain-free maximal isokinetic eccentric knee flexion tests and isometric contractions combined with UST and surface electromyography (sEMG) to measure muscle displacement, scar gap size, and peak torque
- Complete hamstring flexibility testing (active knee extension test) and fill out the Functional Assessment Scale for Acute Hamstring Injuries (FASH)
Part 2 (Adult Acquired Flatfoot Deformity):
- Receive 6 weeks of conservative intervention consisting of wearing custom-molded foot orthoses (for at least 85% of days) combined with progressive PTT eccentric training, short-foot exercises, and calf stretches
- Undergo SWE to evaluate proximal and distal PTT shear wave velocity. Perform progressive isometric foot adduction on an isokinetic dynamometer with UST recording raw radiofrequency (RF) data to measure PTT longitudinal displacement and cross-sectional dynamic torsion
- Complete clinical assessments at baseline, 6 weeks, and 12-week follow-up, including single-leg heel-rise tests, isokinetic strength, ankle range of motion, force-plate balance tests, 5-minute walk tests, and self-reported questionnaires (FFI-R, MSK-HQ)
Part 3 (Elbow Ligament Reconstruction Cohort):
- Participate in an 8-week progressive isokinetic strength training program for the forearm flexor-pronator mass combined with blood flow restriction, alongside grip training
- Undergo dynamic elbow valgus stress testing at 5 N·m torque on an isokinetic dynamometer synchronized with UST and SWE to evaluate regional strain and Young's modulus of the reconstructed mUCLAB
- Complete upper-extremity evaluations before and after training, including shoulder-elbow range of motion, isometric muscle strength using hand-held dynamometry, countermovement push-up (CMPU) power tests on force plates, and the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Athletes with BFlh Strain with Limited Return | Experimental | Behavioral: Nordic Hamstring Exercise TrainingAthletes within 6 months of a unilateral biceps femoris long head (BFlh) muscle injury who have returned to the team but cannot fully participate in high-intensity training or competition. Participants complete an 8-week progressive Nordic hamstring exercise program (twice weekly, progressing from 3 sets of 6 to 3 sets of 12 repetitions) to evaluate changes in muscle displacement and eccentric knee flexor strength. |
| Adults with Symptomatic Adult Acquired Flatfoot Deformity | Experimental | Behavioral: Custom Foot Orthoses and Exercise TherapyAdults aged 18-80 years diagnosed with symptomatic flexible flatfoot (FPI-6 score >= 6 or navicular drop > 9 mm). Participants undergo 6 weeks of conservative therapy consisting of daily custom foot orthoses, progressive posterior tibial tendon eccentric training (twice weekly), daily short-foot exercises, and calf stretching, followed by evaluation at baseline, week 6, and week 12 follow-up. |
| Overhead Athletes with Post-mUCL Reconstruction | Experimental | Other: Forearm Blood Flow Restriction TrainingOverhead athletes aged 18-35 years who have undergone unilateral medial ulnar collateral ligament anterior bundle (mUCLAB) reconstruction and returned to training or competition. Participants complete an 8-week progressive isokinetic strength training program targeting the forearm flexor-pronator mass under blood flow restriction twice weekly. |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (11 listed)
- Aged between 18 and 40 years
- Participated in regular physical exercise for at least 2.5 hours per week
- Experimental group: Sustained a unilateral hamstring muscle injury diagnosed as a muscle strain within the past 6 months, have returned to the team, but currently remain unable to fully participate in training or competition at maximal intensity
- Control group: Sustained a unilateral hamstring muscle injury within the past 6 months, have achieved full return to sport, and are fully able to participate in maximal-intensity training and competition
- Palpation assessment confirms tenderness isolated to the unilateral biceps femoris long head
Key exclusion criteria (17 listed)
- Palpable distinct defect or gap within the injured biceps femoris long head resembling a severe (grade III) muscle tear
- Known systemic diseases that may alter soft tissue composition and mechanical properties
- Other musculoskeletal injuries of the lower extremity within the past 6 months (e.g., fractures)
- History of surgery in the lower extremities
- Any lower extremity orthopedic conditions (e.g., knee osteoarthritis, patellofemoral pain)
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 |
|---|---|---|
| Nordic Hamstring Exercise TrainingAn 8-week progressive Nordic hamstring curl exercise protocol performed twice weekly. Following initial technique instruction, participants perform progressive eccentric hamstring curls starting from 3 sets of 6 repetitions in weeks 1-2 and progressing to 3 sets of 12 repetitions in weeks 7-8. | Behavioural | Athletes with BFlh Strain with Limited Return |
| Custom Foot Orthoses and Exercise TherapyA 6-week conservative program consisting of: (1) Wearing custom-molded foot orthoses daily during ambulatory activities; (2) Progressive eccentric posterior tibial tendon strengthening on an isokinetic dynamometer (twice a week, 3 sets of 15 repetitions); (3) Progressive short-foot exercises (30-40 repetitions daily); and (4) Gastrocnemius and soleus stretching. | Behavioural | Adults with Symptomatic Adult Acquired Flatfoot Deformity |
| Forearm Blood Flow Restriction TrainingAn 8-week progressive isokinetic strength training program targeting the forearm flexor-pronator muscles (pronator teres, flexor carpi ulnaris, brachialis) and handgrip, performed twice weekly. Exercises are performed under pneumatic blood flow restriction set at 70% limb occlusion pressure (LOP) of the brachial artery, at 40-60% of maximal voluntary isometric contraction (4 sets of 20 repetitions per muscle group). | Other | Overhead Athletes with Post-mUCL Reconstruction |
Primary outcome
Longitudinal Muscle Displacement of the Biceps Femoris Long Head (Arm 1)
Time frame: Baseline and Week 8 post-intervention
Longitudinal muscle displacement in millimeters of the middle biceps femoris long head (BFlh) tracked using ultrasound speckle tracking during a 20°/s maximal pain-free isokinetic eccentric knee flexion task.
Posterior Tibial Tendon Dynamic Torsion, Tendon Displacement, and Shear Wave Velocity (Arm 2)
Time frame: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
PTT dynamic torsion and displacement quantified using cross-sectional ultrasound speckle tracking during maximal isometric foot adduction, and tendon mechanical properties evaluated as mean shear wave velocity using shear wave elastography at proximal and distal tibialis posterior tendon.
Regional Strain of the Reconstructed mUCLAB Graft (Arm 3)
Time frame: Baseline and Week 8 post-intervention
Regional engineering strain along the longitudinal axis of the reconstructed medial ulnar collateral ligament anterior bundle (mUCLAB) across proximal, middle, and distal regions, quantified using ultrasound speckle tracking under a standardized 5 N·m dynamic valgus torque.
18 secondary outcomes
Eccentric Knee Flexor Peak Torque (Arm 1)
Time frame: Baseline and Week 8 post-intervention
Functional Assessment Scale for Acute Hamstring Injuries (FASH) Score (Arm 1)
Time frame: Baseline and Week 8 post-intervention
Long Head of Biceps Femoris Muscle Shear Wave Velocity (Arm 1)
Time frame: Baseline and Week 8 post-intervention
Intramuscular Power Doppler Vascularity Grade (Arm 1)
Time frame: Baseline and Week 8 post-intervention
Intramuscular Scar Gap Size During Isometric Contraction (Arm 1)
Time frame: Baseline and Week 8 post-intervention
Hamstring Flexibility (Arm 1)
Time frame: Baseline and Week 8 post-intervention
Revised Foot Function Index (FFI-R) (Arm 2)
Time frame: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Musculoskeletal Health Questionnaire (MSK-HQ) Score (Arm 2)
Time frame: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Visual Analog Scale (Arm 2)
Time frame: Baseline, each treatment session before/after, Week 6, and Week 12 (follow-up)
Single-Leg Heel-Rise Test (Arm 2)
Time frame: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Maximal Voluntary Isometric Foot Inversion Torque (Arm 2)
Time frame: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Five-Minute Walk Test (Arm 2)
Time frame: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Y-Balance Test (Arm 2)
Time frame: Baseline, Week 6 (post-intervention), and Week 12 (follow-up)
Countermovement Push-Up (CMPU) Maximal Vertical Force (Arm 3)
Time frame: Baseline and Week 8 post-intervention
Disabilities of the Arm, Shoulder, and Hand (DASH) Score (Arm 3)
Time frame: Baseline and Week 8 post-intervention
Regional Young's Modulus of Reconstructed mUCLAB (Arm 3)
Time frame: Baseline and Week 8 post-intervention
Shoulder and Elbow Maximal Voluntary Isometric Muscle Strength (Arm 3)
Time frame: Baseline and Week 8 post-intervention
Shoulder and Elbow Active Range of Motion (Arm 3)
Time frame: Baseline and Week 8 post-intervention
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 21 Oct 2026.
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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.
Hsing-Kuo Wang, DPT, PhD study chair
School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Nordic Hamstring Exercise Training, Custom Foot Orthoses and Exercise Therapy and Forearm Blood Flow Restriction Training in people with Hamstring Muscle Strain and Adult Acquired Flatfoot Deformity, run by National Taiwan University Hospital at 1 site in Taiwan.
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 11 inclusion and 17 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: opening soon, as of the sponsor's last update on 21 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Taiwan. 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 Hsing-Kuo Wang, DPT, PhD (+886-2-33668154, hkwang@ntu.edu.tw), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Longitudinal Muscle Displacement of the Biceps Femoris Long Head (Arm 1) (time frame: Baseline and Week 8 post-intervention). The study lists 3 primary outcomes in all. 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 21 Oct 2026.