Residual Eccentric Strength Deficits of Gastrocnemius Muscle and Deep Scar Tissue Thickness in Patients With Tennis Leg: A Cross-Sectional Study
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Enrollment
- 21
- Locations
- 1
- Primary Endpoint
- Eccentric Plantar Flexor Strength Deficit (Percentage)
Study Overview
Brief Summary
This study investigates the relationship between the thickness of deep scar tissue and residual weakness in the calf muscles of patients who have recovered from a condition known as "tennis leg." Tennis leg is a common calf muscle injury caused by a partial tear of the inner part of the gastrocnemius (calf) muscle at the point where muscle meets tendon. While patients often return to daily activities after healing, many continue to experience hidden weakness in their calf muscles, particularly during activities that require the muscle to lengthen under load (eccentric contractions), such as walking downhill, running, or landing from a jump.
This study uses diagnostic ultrasound imaging to measure the thickness of scar tissue that forms inside the muscle after injury. It also uses an isokinetic dynamometer to objectively measure the eccentric (lengthening) strength of the calf muscles. By comparing the injured leg to the uninjured leg in the same person, the study determines whether patients with thicker scar tissue have greater residual strength deficits.
The study enrolls adults aged 18 to 40 years who have had a confirmed unilateral calf muscle tear at least 3 months ago and have returned to normal daily activities. No treatment or intervention is provided. All assessments are performed at a single time point. Understanding how scar tissue relates to persistent muscle weakness could help clinicians better predict long-term outcomes, design more effective rehabilitation programs, and make more informed decisions about when patients are ready to return to sport and physical activity.
Study Design
- Study Type
- Observational
- Observational Model
- Other
- Time Perspective
- Cross-sectional
Eligibility Criteria
- Ages
- 18 Years to 40 Years (Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- Age between 18 and 40 years
- History of unilateral plantar flexor muscle tear (tennis leg) involving the medial gastrocnemius, confirmed by diagnostic ultrasound
- Ultrasound diagnostic criteria: hypoechoic or anechoic fluid collection between the medial gastrocnemius and soleus muscles, with partial or complete disruption of the normal muscle fiber architecture at the myotendinous junction
- Grade I (mild strain, <10% fiber involvement) or Grade II (moderate partial tear, 10-90% fiber involvement) injury
- At least 3 months post-injury
- Clinically healed with return to daily activities
- Ability to perform maximal eccentric plantar flexion as assessed by the Eccentric Heel Raise Test (Single-Leg) (Chen et al., 2009)
Exclusion Criteria
- Bilateral calf injuries
- Grade III (severe/complete) gastrocnemius muscle rupture
- Previous Achilles tendon rupture or surgery
- Previous injuries or surgeries to the lower extremity (other than the index tennis leg injury)
- Neurological disorders affecting lower limb function
- Current acute pain or re-injury at the time of assessment
- Other lower-limb musculoskeletal injuries affecting performance
- Systemic inflammatory or connective tissue diseases
- Popliteal cyst rupture
- Deep vein thrombosis
- Isolated Achilles tendon rupture
- Muscle tumor
Arms & Interventions
Tennis Leg Patients - Post-Healing
Adults aged 18-40 years with a history of unilateral medial gastrocnemius muscle tear (tennis leg, Grade I or Grade II), confirmed by ultrasound, at least 3 months post-injury, who have clinically healed and returned to daily activities. Each participant serves as their own control with the contralateral uninjured limb used for comparison.
Intervention: B-mode Diagnostic Ultrasound - Scar Tissue Assessment (Diagnostic Test)
Tennis Leg Patients - Post-Healing
Adults aged 18-40 years with a history of unilateral medial gastrocnemius muscle tear (tennis leg, Grade I or Grade II), confirmed by ultrasound, at least 3 months post-injury, who have clinically healed and returned to daily activities. Each participant serves as their own control with the contralateral uninjured limb used for comparison.
Intervention: Isokinetic Dynamometry - Eccentric Plantar Flexor Strength Assessment (Diagnostic Test)
Outcomes
Primary Outcomes
Eccentric Plantar Flexor Strength Deficit (Percentage)
Time Frame: Single assessment at the time of enrollment (one study visit)
The percentage difference in eccentric peak torque (Nm) of the plantar flexor muscles between the injured and uninjured limbs, measured using isokinetic dynamometry at 30°/s and 60°/s. Deficit is calculated as: \[(Uninjured - Injured) / Uninjured\] × 100. A higher percentage indicates greater residual weakness.
Deep Scar Tissue Thickness (millimeters)
Time Frame: Single assessment at the time of enrollment (one study visit)
Maximal thickness of deep scar tissue at the musculotendinous junction of the medial gastrocnemius muscle, measured in millimeters using B-mode diagnostic ultrasound in longitudinal and transverse planes. Measurements are compared with the contralateral uninjured limb. Additional scar characteristics recorded include echogenicity (hypoechoic/mixed/hyperechoic), scar continuity and alignment, presence of adhesions, and pennation angle disruption (if visible).
Secondary Outcomes
- Single-Leg Heel Raise Endurance(Single assessment at the time of enrollment (one study visit))
- Time-to-Fatigue During Repeated Plantar Flexion(Single assessment at the time of enrollment (one study visit))
- Ankle Dorsiflexion Range of Motion(Single assessment at the time of enrollment (one study visit))
Investigators
Mariam Ahmed Wagdy
Demonstrator of Physical Therapy
Al Hayah University In Cairo
Study Sites (1)
Identifiers
- NCT ID
- NCT07513779
- Other Study IDs
- CUPT-MSc-2026-MARIAMAW-001
Dates
- First Submitted
- (6 months ago)
- First Posted
- (5 months ago)
- Primary Completion
- (15 days ago)
- Study Completion
- (15 days ago)
- Last Verified
- (29 days ago)
- Last updated
- (yesterday)
Regulatory & Sharing
- FDA Regulated Drug
- No
- FDA Regulated Device
- No
- IPD Sharing Plan
- No
- Has Results
- No