Classic approach to SCFE may fall short

By: Peter Pollack

By Peter Pollack

Slipped capital femoral epiphysis (SCFE) is often treated using in situ fixation with no attempt to reduce the slip. However, long-term follow-up shows that such an approach can result in clinical femoroacetabular impingement (FAI) in nearly one third of hips, leading to a large number of patients with poor function at a relatively young age, according to “FAI and Long Term Outcome of In-situ Fixation for Slipped Capital Femoral Epiphysis,” a paper presented by Daniel J. Sucato, MD.

“SCFE occurs when you’re very young,” explained Dr. Sucato. “In general, we put a screw in the femur and stabilize it just so it doesn’t slip further. Many of those patients do very well in the short term, but in the long term, they may experience early osteoarthritis (OA) and pain. And the reason they get these symptoms and pain is because of the FAI.”

FAI as an outcome of SCFE
To investigate the likelihood of FAI, the research team reviewed the records of all patients who underwent in situ pinning for SCFE at a single institution prior to 1995. Overall, 66 patients (93 hips) met inclusion criteria and returned for clinical and radiographic evaluation. At final evaluation, the research team excluded an additional 3 hips—two that had received total hip arthroplasties and one that had undergone hip joint fusion due to osteonecrosis of the femoral head.

The average age of patients at the time of surgery was 12.6 (±1.7) years, and patients had an average body mass index (BMI) of 27.02 (±5.46). Clinically, 26 hips were unstable and 67 were stable, with 15 slips classified as acute, 35 as acute-on-chronic, and 43 as chronic. Radiographically, 52 patients had mild slips, 38 had moderate slips, and 3 had severe slips.

Poor scores at follow-up
At 20.0 years’ (±4.2) follow-up, 29 hips (32.2 percent) had positive anterior impingement tests, and 23 hips (25.5 percent) had a positive Trendelenburg test on the affected side. Additionally, 31 hips (34.4 percent) had shortening of the affected limb compared to the contralateral side.

Range of motion was also limited. Average flexion was 91.9 degrees, with 24 hips having less than 90 degrees of flexion. Average internal rotation was 4.6 degrees, with 44 hips (48.8 percent) having internal rotation of 0 degrees or less.

Of 89 hips that were evaluated radiographically, 52 (58.4 percent) displayed some degree of OA changes in the joint. Furthermore, the mean Modified Harris Hip Score across all patients was 84.41 (±14.78), with 26 hips scoring less than 80—representing an unsatisfactory outcome.

“We were a little bit surprised that, at around 30 years of age, 30 percent of the patients didn’t show very good results,” said Dr. Sucato. “Almost 70 percent had radiographic impingement, and 30 percent had suboptimal Harris Hip Scores. Many of these patients are probably limiting their activities quite a bit, which is not very good for their overall general health.”

A more aggressive approach
At the time of the study, none of the patients was seeking treatment for lack of internal rotation or FAI. Yet the relatively high number of unsatisfactory outcomes led Dr. Sucato to conclude that taking a wait-and-see approach to young patients with SCFE may not be the best approach.

“I think the data suggest that perhaps we need to be more aggressive in realigning these patients when their symptoms start, as opposed to waiting,” said Dr. Sucato. “We may need to use more advanced imaging techniques,” he continued, “so that we can identify the FAI earlier, and be more aggressive in aligning the femoral heads better.

“Finally, we need to continue to pursue the concept of immediate reduction of the moderate and severe SCFE using the surgical hip dislocation approach and make this a safe procedure to restore normal alignment,” he concluded.

Co-authors on this study were Dinesh Thawrani, MD; Tara Kristof, BA; and Adriana De La Rocha, BS. Dr. Sucato reports the following disclosures: Medtronic.

Peter Pollack is a staff writer for AAOS Now. He can be reached at