Management of Pediatric and Adolescent Sublime Tubercle Injuries: Isolated and Complex Patterns Demonstrate Distinct Etiologies and Radiographic Outcomes.

Background: The aim of this study was to assess the patient demographics, epidemiology, mechanism of injury, and natural history of sublime tubercle avulsion injuries.

Methods: A multicenter retrospective study was performed in which sublime tubercle avulsion injuries were identified by surgeon records and database query of radiology reports. Demographic data and imaging were reviewed for each case, and injuries were classified as type 1 (isolated injuries with a simple bony avulsion or periosteal stripping) or type 2 (complex injuries with an associated elbow fracture or dislocation). Treatment modality and evidence of radiographic healing at a minimum of 3 months were collected.

Results: Forty patients (78% male) with a median age of 15 years (range, 8 to 19 years) were identified with sublime tubercle avulsion injuries. Sixty-eight percent of cases (n=27) were determined to be type 1 injuries, and 32% (n=13) were classified as type 2 injuries. The majority of type 1 injuries (59%) occurred via a noncontact mechanism in overhead-throwing athletes, whereas 100% of the type 2 injuries were sustained via a contact mechanism. Type 1 injuries presented in a delayed manner in 19% of cases, whereas no type 2 injuries (0%) were delayed in presentation. Type 1 injuries infrequently underwent surgical intervention (19%), whereas 54% of type 2 injuries required surgery. Of those that did not undergo initial surgical management at a minimum of 3-month radiographic follow-up, 9/11 (82%) of type 1 injuries and 0/4 (0%) of type 2 injuries demonstrated evidence of healing. Only 1 case required reoperation (type 2 injury).

Conclusions: This series of adolescents with sublime tubercle avulsion injuries expands our understanding of the epidemiology of this rare injury, which was previously only described as a noncontact injury in baseball players. Type 1 injuries are more likely to occur via a noncontact mechanism and generally demonstrate radiographic evidence of healing after a period of rigid immobilization. Conversely, type 2 injuries are more likely to undergo initial surgical intervention, and those managed nonoperatively are less likely to achieve radiographic healing. Further studies are needed to elucidate treatment protocols and long-term functional outcomes.

Level Of Evidence: Level IV-case series.