Slipped Upper Femoral Epiphysis (SUFE)

Presented By Siti Nur Rifhan Kamaruddin

DEFINITION

• Displacement of the proximal femoral epiphysis is uncommon and usually confined to children going through the pubertal growth spurt.

• Boys affected more > girls• If one side slips, there is a 30% risk of the other

side slipping as well

Definition: Slippage of the overlying epiphysis of proximal femur posteriorly & inferiorly due to weakness of the growth plate in relation to metaphysis.

ETIOLOGY• The cause of SUFE is not known. • Trauma may be the precipitating cause but often there is

also an underlying abnormality.• Risk Factor : Unusually tall children : Obese : Delayed gonadal development• Theory : There is imbalance between pituitary growth & gonadal imbalance. Thus, during puberty

growth spurt the immature physis might be too weak to resist stress – imposed by increased body weight.

PATHOLOGY • Following physeal disruption, the femoral shaft

rolls into external rotation and femoral neck is displaced forwards.

• Epiphysis remains seated in the acetabulum.• If slip is severe, the anterior retinacular vessels are

torn. • At back of femoral neck, periosteum is lifted from

bone with the vessels intact -> this may be the only source of blood supply to femoral head.

• Damage to these vessels lead to AVN

• Physeal distruption premature fusion of the epiphysis

• This is accompanied by bone remodeling. • Although there may be a permanent external

rotation deformity and apparent Coxa Vara -> adaptive changes often ensure good joint functions even without treatment.

CLASSIFICATIONTypes of Classification. Based on : • Onset - Acute - Chronic - Acute on Chronic• Functional - Stable - Unstable• Morphological - Mild - Moderate - Severe

Acute : • Pain and weakness. Symptoms <2 weeks• Single episode of trauma• On X-ray : Displaced epiphysis. No remodeling. Chronic:• Intermittent pain in groin & thigh. Symptoms > 2weeks to years• On X-ray : Remodeling and healing seen. Acute on Chronic:• Symptoms last longer than 1 month and there is recent sudden exacerbation pain following trauma

CLASSIFICATION BASED ON SYMPTOMS

Functional ClassificationLODER Classification:Stable SUFE• Pt can walk with or

without crutches.Unstable SUFE• Pt cannot ambulate at

all regardless of duration of symptoms

• This type carries a higher rate of complication

(i.e Avascular Necrosis)

Morphological ClassificationDegree of displacement of the capital femoralEpiphysis from the femoral neck

Mild : < 30 degree Moderate : 30-60 degree

Severe : > 60 degree

CLINICAL FEATURES• Pt is usually a boy of 14/15 years old • Pain in the groin, anterior thigh or knee• He may be limping• Sudden onset • Two-thirds of Pts are overweight & sexually underdeveloped or unusually tall and thin. On Examination• External rotation of the affected leg• The affected left is shorter by 1/2cm• Limited abduction and internal rotation

DIAGNOSIS

• Diagnosis based on clinical examination and radiological investigations

INVESTIGATIONS

• X –Rays - AP and frog lateral views• Ultrasonography - Useful in detection of early slips, joint effusion• CT Scan - Useful in documenting presence of decreased upper femoral neck• MRI Scan - Useful to assess AVN

COMPLICATIONS• Avascular Necrosis - Most serious complication. - In severe cases, SUFE causes the blood supply to femoral head become limited gradual collapse of the bone. - When bone collapses Articular cartilage also collapses - Without cartilage, bone rubs against bone Painful arthritis. - AVN more likely to occur in unstable SUFE. • Chondolysis - Rare but serious complication. - Articular cartilage on the hip joint degenerates very rapidly leading to pain, deformity & permanent loss of motion in the joint.

• Slipping at the opposite hip - Occurs in 30% of cases – sometimes while Pt is in bed. - Always check in the opposite hip with X-ray• Coxa Vara deformity - May occur if displacement is not reduced and epiphysis fuses in its deformed position. - The Pt limps but usually it’s painless - Osteotomy is needed to prevent Osteoarthritis• Secondary Osteoarthritis - Likely to occur if displacement is not reduced - Very likely to occur if there is AVN

TREATMENTMinor Displacement• Displacement of less < one-third Epiphyseal width• Treated by accepting the position & fixing the

epiphysis with two thin threaded pins or screws.• Always done under X-Ray controlModerate Displacement• Displacement of one-third to one-half the

epiphyseal width

Severe Displacement• Displacement is more than one-half the

epiphyseal width • Surgery : Exposing the slip – remove a small

piece of the femoral neck to allow replacement of epiphysis and pinning

REFERENCES

• Apley and Solomon’s Concise System of Orthopedics and Trauma 4th Edition. CRC Press

• SCFE. Kevin D. Walter. Emedicine Medscape http://emedicine.medscape.com/article/91596-overview