Slipped Capital Femoral Epiphysis (SCFE)

What is a slipped capital femoral epiphysis?

Slipped capital femoral epiphysis (SCFE) is a hip disorder that can occur during adolescent development. It happens when the rounded “head” of your teen’s thigh bone (femur) slips out of alignment with the rest of the bone at the “neck.” This causes it to fit poorly in their hip socket and affects how they walk.

Adolescence is a time of rapid growth in all sorts of ways, including bone growth. Long bones grow new tissue from a layer at the “neck” of each rounded end, called the growth plate. New bone growth starts as cartilage before hardening into bone, making this layer softer and weaker than the rest of the bone.

This is why the rounded “head” of the bone (the epiphysis) can slip at the “neck.” In particular, the upper (capital) femoral epiphysis is more likely to slip because it bears the weight of your teen’s pelvis. Weight and growth are the two major factors that make a slipped capital femoral epiphysis more likely.

SCFE may cause limping and pain anywhere along the bone, from the hip to the knee. It usually develops gradually and with no prior injury. It may start in one hip and later appear in the other. It worsens with time, and further complications can occur. Your teen will need surgery to fix it — the sooner the better.

Stable vs. unstable SCFE

Healthcare providers classify a slipped capital epiphysis as either stable or unstable. Most children have a stable SCFE hip that develops gradually. Stable SCFE means you can still put weight on the hip.

An unstable slipped epiphysis is severely misaligned, causing severe pain. You can’t walk on it. It usually takes an abrupt injury to misalign the hip this much. An unstable SCFE hip needs urgent treatment.

What are the symptoms of a slipped capital femoral epiphysis (SCFE)?

Slipped femoral epiphysis symptoms often develop gradually. You and your teen may not be quite sure when they first started. Some of the signs and symptoms you or your teen might notice include:

• Hip pain
• Groin pain
• Leg pain
• Knee pain
• Limp or abnormal walking gait
• Stiffness that worsens with walking
• Difficulty putting weight on one leg
• Difficulty running or bending at the hips
• One hip and leg turned outward
• One leg that looks shorter than the other

What causes a slipped capital femoral epiphysis?

There usually isn’t one single cause of SCFE. Adolescent bone growth and weakness at the growth plate set the stage for it. But many other factors may contribute to a slipped capital femoral epiphysis.

The most likely contributing factors include:

• Childhood obesity. Most teens with SCFE have a BMI over the 95^th percentile for their age.
• Growth spurts. SCFE often occurs with a growth spurt, a short period of rapid bone growth.
• Hormones. Both puberty and obesity can affect your hormone levels, which can impact the growth and strength of your bones. Certain endocrine disorders may also be involved.

Other possible factors include:

• Injuries. A fall or blow to your hip might start the slipping process or make it worse.
• Hip abnormalities. A preexisting condition like hip dysplasia might add stress to your joint.
• Genes. Having a family history of slipped capital femoral epiphysis increases your risk of it.

What is the most common age range for SCFE?

SCFE usually develops between the ages of 11 and 16. The average age of onset is 12. It’s slightly more common in kids assigned male at birth (AMAB) and appears somewhat later in them on average. SCFE isn’t common overall, but it is the most common hip disorder that affects adolescents. It occurs in approximately .01% of teens.

What are the possible complications of slipped capital femoral epiphysis?

A slipped epiphysis changes your body mechanics when you walk, putting weight and stress on parts of your hip joint that aren’t designed to take it. This can cause progressive damage to the joint, including:

• Femoroacetabular impingement. When your femur fits poorly in your hip socket (acetabulum), the bones grind painfully together, and the grinding can damage the cartilage in your hip joint.
• Avascular necrosis. Too much stress or pressure on your slipped capital epiphysis can cut off the blood supply to the bone. When this happens, the bone tissue begins to die.

How do healthcare providers diagnose a slipped capital femoral epiphysis?

Diagnosis begins with a thorough examination of your child’s hip. A healthcare provider will ask your child about their symptoms and gently move the hip in different ways to observe what happens. They’ll follow up with X-rays to confirm the slipped epiphysis. If X-rays don’t reveal SCFE, an MRI usually will.

What is the best treatment for slipped capital femoral epiphysis?

SCFE treatment always involves surgery. It’s important to realign and stabilize the hip joint to prevent further slipping and the complications it can cause. There are different ways of doing this, depending on how stable the SCFE hip is. Most teens only need a simple procedure, involving only one or two screws.

Procedures include:

• In situ fixation. The standard treatment for stable SCFE is a minimally invasive procedure using a technique called arthroscopy.
• Open reduction and internal fixation. For unstable SCFE, a surgeon may have to physically move (reduce) the femur head back into position.

After surgery, your teen will spend two to three months in recovery and rehabilitation. In the beginning, they’ll need to keep weight off the hip and use crutches to walk. When they can use their hip without pain, a physical therapist will guide them in specific exercises to restore their strength and flexibility.

Can SCFE heal on its own?

It’s unlikely. While some healthcare providers have occasionally observed a recent, mild case of SCFE healing on its own, there are too many variables involved in the process to predict or expect this.

It may be that during a growth spurt, the bone briefly weakened and slipped and then self-corrected by means of new bone growth. But usually, this window will be closed by the time you discover SCFE.

What is the prognosis after treatment for slipped capital femoral epiphysis?

The sooner a healthcare provider can diagnose and treat SCFE, the better the outcome is likely to be. Treating stable SCFE before the femur head slips too much can prevent long-term damage to the hip joint. Surgery at this stage is also simpler and easier to recover from. Most kids recover completely.

Unstable SCFE is uncommon and usually related to an injury. But it comes with higher rates of complications, like femoroacetabular impingement and avascular necrosis. These complications tend to require more extensive surgery — possibly including joint replacement surgery if hip arthritis develops.