Case reports: acetabular damage after mild slipped capital femoral epiphysis

Slipped capital femoral epiphysis (SCFE) is a common hip problem in adolescents that results in a cam-type femoroacetabular impingement (FAI) deformity. Although the treatment for mild (slip angle of 0°-30°) and moderate (slip angle of 31°-60°) SCFE has historically been in situ fixation, recent studies have demonstrated impingement-related articular damage, irrespective of slip severity. Our series confirms previous reports that acetabular chondral injury occurs in mild to low-moderate (slip angle of ≤ 40°) SCFE.

We retrospectively reviewed five patients who underwent arthroscopy and femoral osteoplasty within 18 months after in situ stabilization. All had labral and/or acetabular damage.

Osteoarthritis rates after SCFE range from 24% to 92% at 11 to 28 years, depending on how osteoarthritis is defined. Long-term followup suggests patients have acceptable outcomes, but these studies are limited by heterogeneity and a ceiling effect from the instruments used to assess function. Although the femoral deformity remodels, it is unclear what secondary changes occur in the acetabulum. Recent investigations suggest patients are functionally limited after SCFE owing to FAI compared with controls. MRI findings and surgical reports document impingement-related joint damage after SCFE, even in the absence of symptoms. Based on this, some advocate timely correction of the cam deformity inherent in SCFE.

Further study is warranted to determine whether immediate osteoplasty after in situ fixation of mild SCFE is beneficial to limit articular damage and improve long-term outcomes.