Gamekeeper's Thumb

Definition

 

Injury to ulnar collateral ligament of thumb MCPJ

 

Aetiology

 

Initial description

- chronic laxity of British gamekeeper's thumb's 

- no specific trauma

- secondary to breaking pheasant's neck

 

Acute trauma

- snow ski

- ball games

 

Valgus / forced abduction

 

Anatomy

 

UCL

- origin medial condyle metacarpal

- passes obliquely volarly 

- inserts on volar 1/3 of P1 and volar plate

 

Adductor aponeurosis 

- superficial to UCL

- inserts into ulna border thumb extensor mechanism

- via the ulna sesamoid

 

Examination

 

Painful, swollen MCPJ

 

Tenderness along UCL

 

Abduction Stress Test

- in full extension and 30° 

- loss of end point or 30o > other side

- indicates complete rupture

 

X-ray

 

3 types Bony avulsion

 

1. Small fragment pulled away from P1

 

Thumb Bony Gamekeepers

 

2. Large intra-articular fracture involving >1/4 articular surface

 

3. S-H III in paediatric population

 

MRI

 

Look for stenar lesion

- when distal end of UCL

- flipped superficially over adductor aponeurosis

- will not be able to heal

 

A.  Undisplaced

 

MRI UCL Proximal Undisplaced InjuryTorn UCL Minimally Displaced MRI

 

B.  Displaced UCL

 

Management

 

Non operative

 

Indications

- partial tear

- undisplaced complete tear

- undisplaced bony fragment

 

Management

 

6/52 thumb spica

 

Operative

 

Indications for surgery

- complete tear with stener lesion

- large or small displaced bony fragment

- SH III in paediatrics

- chronic injury

 

Displaced Complete tear / Stener Lesion

 

Incidence

- 18 - 43%

 

Types

 

1.   Interposition of the adductor aponeurosis

- between a completely avulsed proximal ulnar collateral ligament injury

- and the proximal phalanx ligament insertion site

 

2.  Interposition between two ends of a mid-substance ligament tear

 

Diagnosis

 

Difficult clinically

- may be able to palpate displaced UCL

 

MRI

 

Technique

 

Dorsal incision along ulna border MCPJ

- Divide Adductor pollicis aponeurosis

- leave cuff for lateral repair

- Identify and repair UCL

 

Fixation

- direct suture if able to

- bony anchors

- through drill holes and over lateral button

- cerclage wire

 

Post op

- 6/52 thumb spica

 

Gamekeepers Thumb Repair

 

Bony Avulsion

 

ORIF Indications

1.   > 25% articular surface

2.   Small avulsion fracture displaced > 5mm

3.   SH III

 

Chronic Injuries

 

1.  Dynamic tendon transfer 

 

Adductor pollicis

- release adductor pollicis from ulnar sesamoid

- attach to base P1

 

2.  Free tendon graft

 

Graft options

- palmaris longus

- fourth toe tendon

 

Technique

- figure of 8 through drill holes

- transverse drill hole base P1

- drill hole head MC

- 6/52 POP

 

3.  Static tendon transfer

 

EPB

- leave attached distally

- weave through drill holes