Residual calf weakness and deep scar thickness after tennis leg

Residual Eccentric Strength Deficits of Gastrocnemius Muscle and Deep Scar Tissue Thickness in Patients With Tennis Leg: A Cross-Sectional Study

Observational Al Hayah University In Cairo · NCT07513779

We try to see if thicker deep scar tissue inside the calf is linked to lasting weakness during lengthening movements in adults 18-40 who recovered from a one-sided tennis leg.

Quick facts

Study typeObservational
Enrollment40 (estimated)
Ages18 Years to 40 Years
SexAll
SponsorAl Hayah University In Cairo Academic / other
Locations1 site (New Cairo, Cairo Governorate)
Trial IDNCT07513779 on ClinicalTrials.gov

What this trial studies

This observational study compares the injured and uninjured legs of adults who had a unilateral medial gastrocnemius (tennis leg) tear to look for a relationship between deep intramuscular scar thickness and eccentric calf strength. Scar thickness is measured with B-mode diagnostic ultrasound and eccentric plantar-flexor strength is measured objectively with an isokinetic dynamometer. Participants are at least three months post-injury, clinically healed, and able to perform a single-leg eccentric heel-raise test, and only grade I–II injuries are included. The study is conducted at the outpatient clinic of the Faculty of Physical Therapy, Alhayah University in New Cairo, in collaboration with Cairo University.

Who should consider this trial

Good fit: Adults aged 18-40 with a confirmed unilateral medial gastrocnemius (tennis leg) grade I or II tear, at least three months post-injury, clinically healed with return to daily activities, and able to perform a maximal single-leg eccentric heel raise are the ideal candidates.

Not a fit: People with bilateral calf injuries, grade III (complete) ruptures, prior Achilles rupture or lower-extremity surgery, or those outside the 18-40 age range are not eligible and are unlikely to benefit from participation.

Why it matters

Potential benefit: If thicker deep scar tissue is linked to lasting weakness, clinicians could tailor rehabilitation to target scar-related deficits and improve functional recovery.

How similar studies have performed: Previous work has used ultrasound and dynamometry to document persistent weakness after calf injuries, but directly linking deep intramuscular scar thickness to eccentric strength in tennis leg is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
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

Where this trial is running

New Cairo, Cairo Governorate

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Tennis LegMuscle Contusion
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.