2019 Research Forum

Presenter & Principal Investigator: Adam Johnson MD R3 Faculty Sponsor: Kieron Barkataki DO

Atraumatic Avulsion of the Fibial Tubercle

Roxana Ardebili MS IV, Adam Johnson MD R3, Kieron Barkataki DO

INTRODUCTION Acute atraumatic knee pain in an adolescent can be difficult to diagnose clinically. A possible cause is Osgood-Schlatter disease which occurs in less than 5% of children age 9-14, especially in those who play sports or who have undergone a growth spurt. This is typically a chronic disease caused by repetitive strain and avulsion of the apophysis of the tibial tubercle leading to chronic separation of patellar tendon from the tibial tubercle. The cycle of avulsion and healing over time can lead to a tender but benign bony prominence. In more rare instances, such as the following case, the avulsion of the tendon is acute and complete, leading to severe pain, swelling, and loss of function of the knee. PURPOSE The patient is a 14-year-old male who presented with left knee pain. The inciting incident occurred 2 days prior to presentation when the patient was running while playing soccer. He endorsed hearing a popping sound and observing immediate swelling, along with acute 8/10 pain over the proximal tibia. The patient was unable to ambulate due to pain but otherwise had full active and passive range of motion. A mobile piece of bone was palpated and tender at the tibial tuberosity, skin was intact with some ecchymosis. No sensory deficits such as numbness or tingling, and full vascular function including equal peripheral pulses and soft compartments were present. Initial x-ray and CT showed an anteriorly displaced avulsion fracture of the tibial tuberosity extending through the metaphysis, physis, and epiphysis along with moderate soft tissue swelling and likely hemarthrosis. This patient was quickly scheduled for internal fixation of the tibial plateau fracture to be performed in the OR to prevent malunion. He was sent home with a hinged knee brace with limited range of motion. DISCUSSION Osgood Schlatter disease is most often benign and self-limiting. A majority of cases occur in children, whose growth plates have not yet ossified. Complete recovery is expected with time and closure of the tibial growth plate. Adults can often be treated with a trial of conservative management, but will require surgical treatment if symptoms of pain persist. One study showed excellent long term outcome in patients who received surgery- ten years after surgery, 87% reported no restrictions in everyday activities and 75% had returned to their preoperative level of sports activity. In the case of our patient, chronic Osgood Schlatter disease likely significantly increased his risk of complete acute tibial tubercle avulsion fracture. These cases must be treated with open reduction and internal fixation, and strenuous activity should be avoided until skeletal maturity. CONCLUSION Atraumatic knee pain is common in the adolescent population. Increasing awareness of Osgood Schlatter disease can facilitate earlier conservative management in order to prevent more permanent damage that would require surgical repair.

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