Incidence of Meniscal Entrapment and Associated Knee Injuries in Tibial Spine Avulsions.

BACKGROUND: Tibial spine avulsions (TSA) have historically been treated as isolated injuries. Data on associated injuries are limited with existing literature reporting wide ranging incidences. The purpose of this multicenter study was to (1) describe the incidence of meniscal entrapment and associated knee injuries in TSA and to (2) compare surgical and magnetic resonance image (MRI) findings for these injuries. Our hypothesis is that tibial spine injuries are not usually isolated injuries, and other meniscal, ligament, and cartilage injuries may be present.

METHODS: MRI and surgical reports for patients with a diagnosis of a tibial spine fracture were retrospectively reviewed. Type of fracture was recorded as noted in the reports along with concomitant meniscal entrapment and osteochondral, ligamentous, and meniscal injury. Images and reports were reviewed by an orthopaedic surgeon at each respective institution.

RESULTS: A total of 163 patients were included in this study. MRI was done for 77 patients and surgery was performed in 144 cases. Meniscal entrapment was found in 39.9% of all patients. MRI diagnosed meniscus, osteochondral, and non-anterior cruciate ligament ligamentous injury was found in 31.2%, 68.8%, and 32.4% of cases, respectively. Surgically diagnosed meniscus, chondral, and non-anterior cruciate ligament ligamentous injury was found in 34.7%, 33.3%, and 5.6% of patients, respectively.

CONCLUSIONS: TSA fractures are associated with significant risk for concomitant knee injuries including meniscal tear, bone contusion, and chondral injury. Incidence of meniscal entrapment found during surgery was high, in spite of low incidence of positive findings by MRI.

LEVEL OF EVIDENCE: Level IV-retrospective case series.