Posterolateral Rotatory Instability



Radius rotates externally in relation to the ulna

- posterior displacement of the radial head relative to the capitellum

- in flexion


Posterolateral rotatory Instability


Anatomy LCL


LCL Elbow




1.  Laxity or tear of ulna LCL

- posterior dislocation / subluxation / perching

- most common cause


2.  Torn CEO

- dynamic restraint


3.  Depressed fracture of radial head / malunion coronoid fractures

- leading to loss of secondary restraint




Dislocation occurs with a valgus ER force pivoting the elbow on the intact MCL





- acute LCL tear after dislocation



- tennis elbow release

- Kocher approach


Ligamentous laxity


Long standing cubitus varus




Posterolateral elbow pain


Describe clunk on full extension


Patient may be able to demonstrate instability




Test combines external rotation / supination with valgus and axial loading


1.  O'Driscoll Pivot Shift Test


Best with patient anaesthetised

- can sublux joint


If patient awake, only get pain and apprehension


Patient supine

- examiner at head of bed

- GHJ full flexed with hand over head

- elbow resembles knee in this position

- forearm supinated

- elbow fully extended


Valgus stress with axial load & slowly flex joint

- at 40o the radial head is subluxed maximally posterolaterally

- radial head becomes prominent as it dislocates

- patient feels apprehension as the radial head subluxes

- past 40o flexion the radial head reduces



- prominent radial head (dislocates)

- pivot

- pain  (apprehension)

- maximum subluxation is at 40o flexion but with increased flexion reduces with snap


2.  Table Top Test


Push up on table with forearms in supination

- radial head subluxes, patient has apprehension

- relieved by thumb pressing on radial head


Table Top Test 1Table Top Test BeforeTable Top Test After





Usually normal

- may be slight widening of radiohumeral joint

- radial head may appear slightly posterior




Difficult to distinguish lateral complex






Does not improve with time

- usually requires surgery if very symptomatic




1. Repair 

2. Imbricate

3. Reinforce/Reconstruct with PL graft




Kocher approach between Anconeus & ECU

- drill holes x 2 base sublime tubercle

- drill holes x 2 at lateral epicondyle (isometric point)

- palmaris graft in figure of 8

- tighten with elbow at 30 - 40o of flexion


Post op

- hold flexed 2/52

- then allow ROM in hinged brace


Lateral Ligament Elbow Reconstruction




O'Driscoll et al JBJS Br 2005

- retrospective review of 44 cases

- some direct repair, some autograft reconstruction

- 86% satisfaction

- better outcomes in reconstruction group