Tibial tubercle avulsion fractures are uncommon injuries in children and adolescents, representing 0.4% to 2.7% of pediatric fractures and fewer than 1% of physeal injuries.
These fractures typically occur in adolescents nearing skeletal maturity, most often in boys, who are more likely to engage in high-impact sports and have greater quadriceps strength.
In a recent review researchers summarized findings from multiple studies and case series, detailing how Tibial tubercle avulsion fractures (TTAFs) result from forceful quadriceps contraction during jumping or from sudden knee flexion during landing. The average patient age was 14.6 years. Radiographs are typically sufficient for diagnosis, though computed tomography and magnetic resonance imaging may be used to evaluate intra-articular extension or soft tissue involvement.
The researchers reported that about 25% of patients exhibited signs of Osgood-Schlatter disease (OSD) during the injury period, suggesting an association with TTAFs, though causality remains unconfirmed. Body mass index (BMI) may also influence risk. One study found that 75% of patients with BMI less than 20 reported pain while squatting, compared with 18% to 32% of patients in higher BMI categories.
The most widely used classification system remains the Ogden system. However, the review found no direct correlation between fracture classification and treatment decisions. Treatment strategies vary. Surgical management was used in 88% of cases, with open reduction and internal fixation performed in 98% of surgical patients. Conservative treatment was generally reserved for nondisplaced fractures or those classified as type IA, IB, or IIA.
Associated injuries included patellar tendon avulsions in 9% of cases and compartment syndrome in 2% to 4%. In one study, compartment syndrome occurred five times more frequently in Ogden type IV fractures compared with other types. Compartment syndrome remains a critical early complication and warrants careful monitoring.
Overall complication rates reached 28%. The most common complication was bursitis requiring implant removal, which accounted for 56% of all complications. Tenderness over the tibial tubercle occurred in 18%, refracture in 6%, genu recurvatum in patients younger than 13 years in 4%, superficial wound infections in 3%, and limb-length discrepancy in 5%, with a mean discrepancy of 1.4 cm.
Functional outcomes were generally favorable. In one systematic review, 98% (250 of 255) of patients regained full range of motion within a mean of 22.3 weeks. Additionally, 97% (248 of 255) returned to preinjury activities after an average of 28.9 weeks. Bone union was observed in 99% (333 of 336) of cases.
“The flexibility in treatment options likely emerges from a combination of factors, including the relative rarity of TTAFs and the favorable prognosis associated with these fractures, irrespective of whether they are managed conservatively or through surgical intervention,” said Hailun Yao, of the Department of Orthopedics, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China, and colleagues.
While prognosis is good with appropriate treatment, the researchers noted ongoing variation in management strategies and emphasized the need for further research to clarify the influence of risk factors such as OSD and BMI and to establish standardized treatment protocols.
The authors reported no conflicts of interest.
Source: Pediatric Discovery
