The Bone School

Myers & McKeever classification

Type I:   Undisplaced avulsion fracture

Type II:  Anterior portion displaced & hinged

Type IIIA:   Displaced

Type IIIB:   Displaced & Rotated

Management

I - III A 

Attempt closed reduction

- anaesthesia / II control

- long leg cast in full extension

- trap fragment under condyles

Block to reduction

- usually medial meniscus / intermeniscal ligament

IIIB & Failed MUA

1.  Medial arthrotomy / arthroscopically

- need to remove portion of fat pad for visualisation

- intermeniscal ligament usually blocks reduction

- removed callus / hematoma

- replace fragment under intermeniscal ligament

- want to impact fragment to tension stretched ACL

2.  Repair Options

A.  No 2 suture

- bunnell suture through ACL above bony fragment

- pass 2 x limbs through bony fragment

- insert beath pins to retrieve suture limbs through tibial insertion

- two separate tunnels

- tie over bony bridge in tibia

- protect in plaster in extension

B. ORIF physeal sparing screw

- II guided

- directed posteriorly and obliquely

Outcomes

Stability

Some stretch of ligament occurs, but most knees are stable

Malunion

Occasionally fragment can block full extension