Derotational osteotomy in SCF

E complicated with avascular n

ecrosis

YUMC

Hui Wan Park, Hyun Woo Kim

Yonsei University College of Medicine

Female /14

CC : Out-toeing gait with painful LOM of left

hip

PH

•2000. 05 - pinning-in-situ for SCFE lt.

•2000. 09. -- removal of penetrated screw due to AVN

•2001. 05. 31. – adductor tenotomy

•2002. 01. 03. -- cheilectomy

Hinge abduction Cheilectomy

02. 01. 01. 02. 01. 12.

Improvement after cheilectomy

• Further flexion of hip 75 95

• Further abduction 0 15

PE

• AGF : 90

• IR : -10, ER : 50

• Leg length discrepancy : 84.2/82.5 (1.7cm)

Aspherical incongruous head

04. 07. 21.

Subtrochanteric osteotomy30o derotation internally

04. 07. 21. 05. 07. 15.

Improvement after derotation osteotomy ( one year F/U )

• Less pain around hip & knee j. during gait

• Easier abduction

• IR : -10o 10o

Causes of increased external rotation in SCFE

• Decreased anteversion – retroversion

• Collapse of femur head due to avascular necrosis

Mechanical factors in SCFE

Prichett (1988)

Slipped epiphysis patients have relative retroversion, and this generates increased saggital plane shear stress at the proximal femoral growth plate

Rt. ; retroversion 9o

Lt. : retroversion 2o

Retroversion of femur head

A cause of pain & osteoarthritis

Tonnis (1991)

Rotation of the femur internally or externally from neutral position necessitates increased abductor muscle force to maintain a level pelvis

Merchant (1965)

A predictor of risk for stress fracture

Gilardi et al (1987)