Abstract
Purpose
Rectus femoris avulsion (RFA) injuries in paediatric patients are currently managed conservatively. However, the proximal attachment of the rectus femoris muscle lies in a critical zone in the hip joint with attachments to the anterior hip capsule and anterior inferior iliac spine. Violent avulsions therefore could cause damage to the adjacent acetabular labrum and articular cartilage initiating a process leading to early degenerative changes in the hip. To date, the association between rectus avulsions and labral tears has not been studied.
Method
The complete medical records of patients who were presented to McMaster University Medical Center with rectus femoris avulsions between 1983 and 2008 who were between the ages of 2 and 18 were identified. Patients were included if they had documented plain radiographs and magnetic resonance arthrography images of their hip. MRIs were reviewed by an independent musculoskeletal radiologist blinded from the history of the patients.
Results
16 patients were identified in the database with rectus femoris avulsions diagnosed on plain radiograph and 7 were included in the study with documented MRIs. The average age of patients was 13 (Range 7–16). All injuries occurred during sports activity with 43% occurred during running, 29% with kicking during soccer and during skating acceleration while playing hockey. One patient had a concurrent sartorius avulsion. All patients with rectus femoris avulsions had labral tears identified on MRI in the zone adjacent to rectus insertion. All patients were treated conservatively. Clinical records suggested 72% of patients were still limping and 86% were experiencing residual pain at last follow-up.
Conclusion
Patients with rectus femoris avulsions may be at risk for concurrent traumatic labral tears. These patients should be assessed for labral pathology including a clinical examination and MRI arthrography.
Level of Evidence: Level IV