Slipped Upper Femoral Epiphysis

Scenario

A 13 Year old overweight boy is brought in by his mother. He is limping and complaining of pain in his left hip.

Screenshot-2022-04-28-at-07.09.10

Imaged sourced from: https://en.wikipedia.org/wiki/Slipped_capital_femoral_epiphysis used under CC BY-SA 3.0

This is a frog leg lateral plane film radiograph of an unknown skeletally immature patients Left Hip. The most obvious abnormality is a disruption in Kline’s line (Trathawan’s sign positive) representing a slipped upper femoral epiphysis.

I would take a full history. Pertinent features in the history would include: infection, sepsis, endocrine history (esp if under 10), hx of trauma or NAI.

I would then examine the joint and the joints above and below

I would then perform investigations: XR AP and frog leg lateral, bloods including inflammatory markers and endocrinological bloods (TFTs, Creatinine, urea)

Loder classification

Stable

Unstable

Able to bear weight with or without crutches

Minimal risk of osteonecrosis

Good prognosis 96%

Unable to bear weight

Associated with higher risk of osteonecrosis

Good prognosis in 47%

 

Southwick angle

 

Mild

<30 degree

Moderate

30-50 degrees

Severe

>50 degrees

Line drawn along the superolateral margin of the femoral neck.

Trathawan’s sign is when klines line does not intersect the epiphysis.

Main supply is medial femoral circumlex artery

Lateral circumflex contributes

Superior and inferior gluteal arteries also contribute

Arteries of ligamentum teres (obturator)

Operative treatment

  • Percutaneous insitu fixation
    • Goal to stabilise the epiphysis from further slippage
    • Screw perpendicular to physis
    • 5 threads must cross the physis
    • Stable slips can bear weight
    • Unstable partial weight bearing
  • 2 screws higher biomechanical stability. Capsulotomy also controversial

Fixing the contralateral side

  • Initial split <10 years
  • Those with open triradiate cartilate
  • Obese males
  • Endocrine disorders

There is obligate external rotation on flexion of the hip and loss of internal rotation