What's the Diagnosis? By Dr. Lynn Manganiello
A 59 yo male presents after fall from standing with right knee pain. Pt describes feeling a "pop" and notes that his knee is visibly distorted after the fall. An x-ray is shown. What's the diagnosis? Scroll down for answer.
Answer: Quadriceps/patella tendon rupture
Mecahnism: fall onto flexed knee or forceful contraction of quadriceps
Presentation: pain, swelling, deformity, inability to extend the knee or maintain extension against gravity
Patella tendon rupture usually in age <40
quadriceps tendon rupture usually in age >40
- patella tendon rupture: superior dislacement of patella or "patella alta"
- quadricepts tendon rupture: inferior displacemtn of pateall or "patella baja"
- Complete tear - orthopedic consultation in ED for surgical repair
- Incomplete tear (intact extensor mechanism) - knee immobilizer, crutches, follow-up orthopedics within one week
Bonus points: bony structure posterior to the knee on this x-ray = fabella
Bengtzen, RR, Glaspy, JN, Steele, MT. "Knee Injuries." Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 8eEds. Judith E. Tintinalli, et al. New York, NY: McGraw-Hill, 2016, pg 1857-1864.?