| CASE OF THE MONTH - January 2005 |
 |
|
History:
A 13-year-old running back injured his left knee while being tackled. He sustained a blow to the anterior/medial aspect of his left knee while in a flexed position. He complained of immediate pain and was unable to continue activities. He did not recall hearing or feeling a pop, but had immediate swelling of his knee. There is no history of prior knee injury. There is no significant past medical or surgical history. He takes no medications and has no known drug allergies.
Initial treatment by the coach included ice, a compression wrap, and crutches.
He was evaluated the following day by the athletic trainer and team physician. |
Physical Exam:
Examination revealed a well-developed male in moderate distress because of pain. He had a moderate sized effusion with soft tissue swelling around the superior/lateral aspect of his patella and distal femur. He was not able to bear weight or fully extend his knee because of pain. PROM: (L) 20-90 degrees; (R) 0-130 degrees. The leg was warm and well perfused. The patient was tender over his quadriceps tendon, superior pole of the patella, and distal femur. He had patellar apprehension. There was no joint line tenderness. He had normal pulses and his sensation was intact. Ligament testing was not performed because of the patient’s pain. He was placed in a knee immobilizer and sent for radiographic examination. |
Initial Differential Diagnosis based on the History and Physical:
1) Anterior or posterior cruciate ligament tear
2) Patellar subluxation or dislocation
3) Capsular injury
4) Occult fracture
5) Osteochondral injury
6) Lateral or medial collateral ligament sprain
7) Quadriceps tendon strain or rupture |
Diagnostic studies:
A. Plain Radiographs: AP and lateral views of the left knee with comparison views (right knee).
AP and lateral views of the left knee revealed a Salter-Harris II fracture of the distal femoral epiphysis with anterior and superior displacement of the epiphysis. |
Final Diagnosis:
Salter-Harris II fracture of the distal femoral epiphysis. |
Treatment and Outcome:
The patient was placed in a knee immobilizer and sent for orthopedic evaluation. He was taken to the operating room for closed reduction under anesthesia. A long leg cast was applied in 60 degrees of knee flexion, and post-reduction x-rays revealed restoration of normal alignment. There were no complications.
The patient underwent serial casting with removal approximately 5-½ weeks post injury. Repeat x-rays revealed excellent alignment with early healing. He was placed in a hinged knee brace with progressive weight bearing along with quad and hamstring rehabilitation. He has had an excellent outcome with full return to activity |
Discussion:
Fractures of the distal femoral epiphysis are uncommon injuries, accounting for 1-6% of all physeal injuries, and 1% of all fractures seen in children. 1
There is a high incidence of physeal growth disturbances, which may lead to limb length discrepancies and progressive angulation deformities. Other complications include popliteal artery or peroneal nerve injury, recurrent displacement, and knee joint instability. Treatment can be conservative or operative depending on the age of the child and the severity of injury. The goal is anatomic reduction with restoration of full range of motion, along with improving quad and hamstring strength and flexibility. Most athletes are able to return to normal activities after 4-6 months. |
Referencess:
Rockwood and Green’s Fractures in Children. Fourth Edition, pp.1233-126 |
Case provided by:
KYLE J. CASSAS, M.D., is assistant professor of family medicine at the University of Texas |