This 24-year-old professional athlete “pulled up” while running. This brings up some questions. Do you have the answers?
- 1. What is your diagnosis?
- 2. The green and blue arrows on image 1 (proton-density STIR axial) point to:
- a. Semimembranosus oblique and popliteal heads
- b. Biceps short head and long head
- c. Semitendinosus and semimembranosus
- d. Vastus lateralis
- e. Semitendinosus long and lateral heads
- 3. On image 2 (T2 fast-spin echo axial), the red arrow points to a subtle finding. What is it?
- 4. The yellow arrow (image 2) points to what finding?
- 5. Why are the soft tissues so swollen in this hamstring injury?
- 6. In a high-performance athlete, how many descriptive criteria can you think of to help define the character and severity of the tear?
Let’s go over the answers:
- 1. Hamstring tear, clinical strain
- 2. b. Biceps short head and long head
- 3. Fraying of the superficial muscle fibers and injury of the epimysium of the biceps short head (very subtle)
- 4. Swelling of the intermuscular fascial space between the biceps short head and long head. This space is usually composed of fibroelastic tissue only.
- 5. Because of the superficial position of the hamstring tears there is inordinate superficial swelling.
- 6. Descriptive criteria for hamstring assessment include:
- a. Percent cross-sectional area (< 25%, 25-50%, > 50%, 100%)
- b. Number of muscles or heads involved
- c. Length of tear
- d. Fluid collection
- e. Muscle subunit involvement or crimping versus macroretraction
- f. Tendon or myotendinous involvement
- g. Hemorrhage or hematoma
This is a start! In a future case we will update you on how we grade such injuries with the above descriptive criteria and how we use this information to decide on the convalescence period. This patient’s convalescence period was 4-6 weeks. For more case review, check out MRI Online.