Safely Reducing the Incidence of Contralateral Slipped Capital Femoral Epiphysis: Results of a Prospectively Implemented Prophylactic Fixation Protocol Using the Posterior Sloping Angle

Abstract

Background: Bilateral slipped capital femoral epiphysis (SCFE) is common. The management of the contralateral hip in unilateral SCFE remains controversial. The aim of this study was to report on the clinical outcomes using a posterior sloping angle (PSA) threshold of 14.5 degrees for prophylactic fixation in preventing contralateral SCFE. Methods: Having previously established through a retrospective study that PSA was predictive of future slip, the authors put in place a protocol where patients with unilateral SCFE who had a PSA ≥14.5 degrees on the contralateral side were offered prophylactic fixation. Those with unilateral SCFE presenting between January 2008 and December 2018 with a minimum of 12-month follow-up were included. Patients with renal or endocrine disorders were excluded. Primary outcomes were the number of slips prevented, the number needed to treat, and the complication rate. Results: Of the 219 patients who were included, 114 (52.1%) underwent prophylactic fixation. A PSA threshold of 14.5 degrees prevented 77% of subsequent slips with a number needed to treat of 2.4 in our population. There were no cases of chondrolysis, avascular necrosis, or periprosthetic fracture associated with prophylactic pinning. Conclusions: Prophylactic fixation using a PSA of 14.5 degrees is safe, decreases unnecessary intervention, and reduces 77% of subsequent SCFE. The PSA can increase over time and the authors recommend that the protocol be applied for the duration of follow-up. Level of Evidence: Level III

Socioeconomic Deprivation and its Associations With Follow-up Compliance After In Situ Pinning of Slipped Capital Femoral Epiphysis

“…Given the importance of SCFE follow-up, it is vital to consider these trends when developing treatment plans for SCFE in a diverse patient population. Although there is not yet consensus on the indications for prophylactic contralateral pinning in patients with unilateral SCFE,11,12,16 the present study’s data may be relevant when making recommendations for or against prophylactic treatment. Although SES alone certainly should not dictate whether or not to perform prophylactic fixation, the present study’s data does highlight the importance of considering these factors when planning close surveillance for a potential contralateral slip.…”

“…11 Whether the latter is necessary for improved outcomes remains controversial and a point of discussion among orthopaedic professionals. [11][12][13][14][15][16] Regardless of surgical procedure, all treatments of SCFE carry the possibility of postoperative complications such as avascular necrosis, femoroacetabular impingement (FAI), and chondrolysis. [17][18][19] If prophylactic fixation has been deferred, then patients additionally need to be followed for subsequent contralateral SCFE.…”

“…Treatment varies depending upon SCFE severity but includes in situ pinning of the affected hip and possible prophylactic pinning of the contralateral, unaffected hip 11. Whether the latter is necessary for improved outcomes remains controversial and a point of discussion among orthopaedic professionals 11–16…”

What’s New in Pediatric Orthopaedics

“…St George et al reported using a posterior sloping angle threshold of 14.5° for prophylactic fixation in preventing contralateral SCFE, which prevented 77% of subsequent SCFEs while decreasing unnecessary intervention. The authors also stated that a posterior sloping angle can increase over time and recommended that the protocol be used for the entire follow-up 66 .…”

Surgeon Preference for Prophylactic Contralateral Fixation in Slipped Capital Femoral Epiphysis (SCFE) Patients: A Nationwide POSNA Survey Study

“…Amid this controversy, many researchers have attempted to understand the risk factors for developing contralateral SCFE to predict which patients might benefit from prophylactic pinning. For instance, several authors have shown that younger age, greater body mass index (BMI), 9 endocrine abnormalities, 10,11 skeletal immaturity, 12 and a plethora of radiographic measurements 13 carry an increased risk for contralateral SCFE.…”