Slipped Capital Femoral Epiphysis Treatment & Management

Medical Issues/Complications

Treatment of slipped capital femoral epiphysis (SCFE) is emergent; therefore, early and accurate diagnosis is paramount. There is no role for observation or attempts at closed reduction.

Classification schemes are as follows:

• Determine whether the SCFE is acute (< 3 weeks), chronic (3+ weeks), or acute on chronic (3+ weeks of symptoms with acute exacerbation or change).
• Determine whether the SCFE stable (able to bear weight) or unstable (non-weight bearing). This determination has become more important than acute versus chronic due to the fact that unstable patients have been found to have a high complication rate.
• Determine the radiographic classification. This is determined by the percentage of displacement of the hip in relation to the neck. Type I is less than 33% displacement, type II is 33-50% displacement, and type III is greater than 50% displacement.

Prophylactic treatment of the asymptomatic hip remains controversial. In Europe, the majority of patients receive prophylactic fixation of the contralateral hip. Each case should be approached individually, and the benefits and risks should be weighed when contemplating surgery on the unaffected hip.

In a review of the literature, prophylactic treatment may be considered in patients younger than 10 years or patients affected by various endocrinopathies because these individuals have higher relative risks for bilateral involvement. Prophylactic treatment should also be considered in a patient or family that is unreliable. In a typical patient who presents with unilateral SCFE, the parents should be warned of possible sequential bilateral involvement. The need for close follow-up and early operative intervention if the other hip becomes symptomatic must be understood by the family.

Delays in diagnosis or treatment can be very detrimental to the patient's outcome. The slip may progress, and increased severity of SCFE leads to early degenerative arthritis. With a diagnostic or treatment delay, stable slips may become unstable, which leads to higher rates of AVN.

Surgical Intervention

At this time, immediate internal fixation in-situ using a single cannulated screw is the treatment of choice of SCFE. Fixation allows early stabilization of the slippage, enhancement of physeal closure, prevention of further slippage, and amelioration of symptoms with minimal morbidity.^{[24, 25]} Unstable or grade III slips may require gentle repositioning to improve alignment. Revision of the screw fixation may be needed if the child "outgrows" the screw, placing the child at risk for a repeat slip.

Prophylactic fixation of the unaffected hip in unilateral SCFE remains controversial.^{[3, 26]} Each case should be approached individually. However, stronger consideration for the prophylactic fixation should be given to patients with endocrinologic or metabolic comorbidities, or patients who fall outside of the usual age range (10-16 y).

Evidence suggests that if surgical intervention occurs within 24 hours of SCFE onset, significantly fewer complications occur (7% AVN). However, if surgical intervention occurs between 24 and 48 hours, the AVN rate dramatically increases (87.5%). This risk decreases to 32% if the procedure is performed after 48 hours. True cause and effect among onset, diagnosis, and intervention cannot be truly ascertained; thus, urgency with surgical intervention is still the unquestioned rule.

Osteotomy of the proximal femur is not indicated as the primary procedure for SCFE. However, it may be needed as a secondary procedure for repositioning of the femoral head to improve functional range of motion, or as a primary procedure for patients with severe morphologic displacement.

Bone-graft epiphysiodesis in combination with internal fixation or casting is advocated by some surgeons, but the procedure is associated with a high learning curve, a high prevalence of AVN and chondrolysis, poor initial fixation, prolonged operative time, increased intraoperative blood loss, and loss of epiphyseal position.^[27]

Historically, spica casts were used^[28] ; however, because of the high morbidity (eg, AVN, chondrolysis) and difficulty in applying and maintaining these casts, especially in patients who are obese, spica casts have fallen out of favor.

Two techniques to correct moderate and/or severe SCFE have been evaluated^{[29, 30]} :

Witbreuk et al performed epiphysiodesis combined with early Imhauser intertrochanteric osteotomy in 28 patients (32 hips) to downgrade moderate and severe SCFE to diminish mechanical impingement and prevent osteoarthritis.^[29] At a median follow-up of 8 years (range, 2-25 y), the patients were performing well clinically, functionally, and socially. In addition, there were no radiologic signs of chondrolysis or avascular necrosis, and greater than 80% of the patients did not have signs of osteoarthritis.^[29]

Lawane et al retrospectively evaluated the Dunn procedure in adolescents aged 10-15 years with severe SCFE (epiphyseal slippage of 60-90 degrees) with regard to avascular necrosis of the femoral head.^[30] Of the 25 cases, 15 achieved good clinical and radiologic results, but 10 had immediate or late complications, for a 40% complication rate. Of the 8 immediate complications (32%), 4 were necroses (16%), 2 of which resulted in arthritis; 3 were chondrolyses, all of which progressed to arthritis; and 1 was mechanical.^[30] Before 10-year follow-up, 2 arthrodeses and 3 hip replacements were performed. At long-term follow-up, an additional 2 late deteriorations occurred despite initial favorable clinical and radiologic outcomes.

The investigators concluded that although the Dunn procedure limits the vascular risk of surgical correction of the SCFE displacement, there are issues of concern, including "tricky" technical aspects of the procedure and the risk of necrotic complication, at rates up to 17% in other reported series.^[30] Lawane et al reported a necrosis rate of 16%, which they found unacceptable in view of the immediate loss of joint function in the adolescent patients. Their preferred approach to severe SCFE is arthrotomy followed by a direct approach to the displacement with associated anterior cuneiform neck resection.^[30]

Consultations

Orthopedic surgery consultation should be immediate in cases of SCFE.

Endocrinology consultation may be indicated for patients presenting earlier than age 10 years of or later than age 16 years. Also, if there are any concerns for endocrinopathy found on history or physical examination, consultation may be necessary to help evaluate for a potential disorder.