Gamekeeper's Thumb

High Yield Overview

GAMEKEEPER'S THUMB

Skier's Thumb | UCL Injury | Stener Lesion | Pinch Grip Stability

80%Complete tears with Stener lesion

30°Laxity threshold for complete tear

15°Side-to-side difference = significant

90%MRI sensitivity for Stener lesion

Critical Must-Knows

Stener lesion: UCL stump flips superficial to adductor aponeurosis - aponeurosis blocks healing - MANDATORY surgery
Test in 30° flexion to isolate proper collateral ligament (main stabiliser). Extension tests accessory UCL + volar plate
Instability criteria: greater than 30° laxity OR greater than 15° difference to normal side OR no firm endpoint
X-ray FIRST before stress testing - may have avulsion fracture that stress could displace
Chronic cases (greater than 6 weeks): Primary repair not possible - requires tendon graft reconstruction or MCP fusion

Examiner's Pearls

"
Gamekeeper's = chronic (Scottish rabbit neck-wringing), Skier's = acute (ski pole strap)
"
Palpable mass proximal to MCP = Stener lesion clinically
"
Complete tear conservative treatment failure rate is high because most have Stener lesion
"
Protect radial sensory nerve during surgical repair - runs in surgical field

Clinical Imaging

Imaging Gallery

Multi-modal imaging of gamekeeper's thumb showing anatomy, X-ray, and MRI — Comprehensive imaging evaluation of gamekeeper's thumb demonstrating the systematic diagnostic approach. **Panel A (Anatomical Diagram)**: Labels the critical structures including the ulnar collateral ligament (UCL), metacarpophalangeal joint (MP), proximal phalanx (PP), and distal interphalangeal joint (DIP). Understanding this anatomy is essential for interpreting imaging and planning surgical repair. **Panel B (Plain Radiograph)**: Thumb X-ray with arrow indicating pathology - demonstrates the MANDATORY first step in evaluation (X-ray BEFORE stress testing) to identify bony avulsion fractures that could be displaced by clinical examination. Approximately 20-30% of gamekeeper's thumb cases have an avulsion fracture at the UCL insertion. **Panels C and D (MRI Sagittal Views)**: Show soft tissue detail with arrows pointing to UCL disruption and surrounding edema. MRI is the GOLD STANDARD for identifying Stener lesions - the absolute surgical indication where the torn UCL stump becomes trapped superficial to the adductor pollicis aponeurosis, preventing healing. MRI has 90% sensitivity for detecting Stener lesions and guides the decision between conservative management (partial tears) versus surgical repair (complete tears with Stener lesion). This multi-modal approach mirrors clinical practice: X-ray first (rule out fracture), then if complete tear is suspected based on instability criteria (>30° laxity, >15° asymmetry, no endpoint), proceed to MRI to identify Stener lesion before surgery.Credit: Source article via PMC via Open-i (NIH) (Open Access (CC BY))

Ultrasound and MRI correlation in UCL injury diagnosis — Correlation between ultrasound and MRI imaging of thumb ulnar collateral ligament injury. **Panels A and B (Anatomical Diagrams)**: Show normal thumb anatomy with blue arrows indicating the UCL and red arrows highlighting pathology - provides orientation for interpreting the imaging studies. **Panels a and b (Ultrasound Images)**: Display longitudinal axis ultrasound views of the thumb UCL with arrows marking ligament disruption and abnormal echogenicity. Ultrasound offers REAL-TIME DYNAMIC assessment - the examiner can apply stress while imaging to assess ligament integrity and identify laxity. **Panels E and F (MRI Images)**: Demonstrate the same pathology seen on ultrasound, confirming the diagnosis with the gold standard modality. The correlation between ultrasound and MRI validates ultrasound as an emerging diagnostic tool for gamekeeper's thumb. ADVANTAGES OF ULTRASOUND: (1) Point-of-care evaluation in clinic, (2) Dynamic stress testing under direct visualization, (3) Cost-effective compared to MRI, (4) Can identify Stener lesion (UCL superficial to adductor aponeurosis) in experienced hands, (5) Bilateral comparison readily available. While MRI remains the gold standard, ultrasound is increasingly used for initial assessment and can guide the decision for MRI when findings are equivocal. The key is identifying whether the UCL stump is superficial (Stener) or deep (non-Stener) to the adductor aponeurosis - this determines surgical urgency.Credit: Source article via PMC via Open-i (NIH) (Open Access (CC BY))

Critical Exam Points

Stener Lesion

Absolute surgical indication. Interposition of Adductor Pollicis aponeurosis prevents healing. Clinically presents as a palpable mass proximal to MCP joint.

X-ray First

Never stress test before X-ray. Stressing a non-displaced fracture can displace it. Always rule out bony avulsion first.

Testing Position

Test in 30° flexion to isolate the proper collateral ligament (PCL). Extension testing assesses the accessory UCL and volar plate.

Anatomy

Ulnar Collateral Ligament

Structure:

Proper Collateral Ligament (PCL): Tight in Flexion. Main stabiliser against valgus stress.
Accessory Collateral Ligament (ACL): Tight in Extension. Attaches to volar plate.

Stener Lesion:

The Adductor Pollicis aponeurosis (hood) lies over the UCL.
When UCL tears distally, the stump can flip and become trapped superficial to the aponeurosis.
The bone site is deep to the aponeurosis.
Healing is impossible because the aponeurosis blocks contact ("Interposition").

Testing Technique

Always test the normal side first! Laxity varies. A 'soft end point' is more specific for a tear than the absolute degree of angulation. Test in 30° flexion to isolate the Proper UCL (the critical one).

Clinical Context: If fracture is present on X-ray, do NOT stress test vigorously.

At a Glance

Gamekeeper's thumb refers to chronic UCL injury while Skier's thumb is the acute variant, both involving injury to the ulnar collateral ligament of the thumb MCP joint from forced abduction. The critical pathology is the Stener lesion where the torn UCL flips superficial to the adductor aponeurosis, preventing healing and mandating surgical repair. Stress testing should be performed in 30° flexion to isolate the proper collateral ligament, with greater than 30° laxity or greater than 15° asymmetry indicating complete tear. Partial tears are treated with thumb spica immobilisation for 4-6 weeks, while complete tears with Stener lesion require surgical anchor repair to restore pinch grip strength and prevent chronic instability with CMC arthritis.

Mnemonic

PAVUCL Components

Proper UCL

Dorsal, tight in FLEXION - main stabiliser, test at 30° flexion

Accessory UCL

Volar, tight in EXTENSION - test in full extension

Volar plate

Also tightens in extension - not primary stabiliser

Memory Hook:Proper = Primary = test in Flexion (Proper Flexes)

Mnemonic

SAILStener Lesion Criteria

Superficial

UCL stump lies ABOVE adductor aponeurosis

Aponeurosis

Adductor pollicis hood blocks contact with bone

Interposition

Tissue interposed between ligament and insertion

Ligament won't heal

Cannot heal = mandatory surgical repair

Memory Hook:The ligament SAILs outside the aponeurosis and can't get back in

Mnemonic

S-P-CUCL Injury Grading

Strain (Grade I)

less than 15° laxity, firm endpoint - splint 2-3 weeks

Partial (Grade II)

15-30° laxity, endpoint present - cast 4-6 weeks

Complete (Grade III)

greater than 30° or greater than 15° difference, no endpoint - SURGERY

Memory Hook:S-P-C: Severity Progressively Climbs

Overview

UCL Injury Overview

Terminology:

Gamekeeper's thumb: Chronic UCL injury (attritional)
Skier's thumb: Acute UCL injury (traumatic)
Both involve ulnar collateral ligament of thumb MCP joint

Epidemiology:

Common sports injury (skiing, rugby, AFL)
Fall on outstretched thumb with forced abduction
Ski pole strap mechanism classically described

Acute vs Chronic UCL Injury

Feature	Skier's Thumb (Acute)	Gamekeeper's Thumb (Chronic)
Mechanism	Single traumatic event	Repetitive stress
Presentation	Acute pain, swelling	Gradual weakness, instability
Treatment	Repair if Stener lesion	Reconstruction or fusion

Anatomy

UCL Anatomy

Two Components:

Proper collateral ligament (PCL): Tight in flexion
Accessory collateral ligament (ACL): Tight in extension

Key Relationship:

Adductor pollicis aponeurosis lies superficial to UCL
In complete tears, UCL can flip outside the aponeurosis
This is the Stener lesion

UCL Components

Component	Position	Testing Position
Proper UCL	Dorsal	30° flexion
Accessory UCL	Volar	Full extension
Adductor aponeurosis	Superficial to both	N/A - covers UCL

Classification

UCL Injury Grading

Grade I - Strain:

Microscopic tears, ligament intact
Less than 15° laxity, firm endpoint
Treatment: Splint 2-3 weeks

Grade II - Partial Tear:

Partial disruption of ligament fibres
15-30° laxity, still has endpoint
Treatment: Thumb spica 4-6 weeks

Grade III - Complete Tear:

Complete rupture of UCL
Greater than 30° laxity or greater than 15° difference to normal side
No firm endpoint
Treatment: Usually surgical (Stener lesion likely)

UCL Injury Classification

Grade	Laxity	Endpoint	Treatment
I - Strain	Less than 15°	Firm	Splint 2-3 weeks
II - Partial	15-30°	Present	Cast 4-6 weeks
III - Complete	Greater than 30° or 15° difference	Absent	Surgery

Clinical Assessment

History and Examination

History:

Mechanism (fall on abducted thumb, ski pole, ball)
Time since injury
Weakness of pinch grip
Previous injuries

Inspection:

Swelling over ulnar MCP
Bruising
Palpable mass (Stener lesion)

Stress Testing:

Always test normal side first
Test in 30° flexion (proper UCL)
Test in extension (accessory UCL)
Assess endpoint quality (soft vs firm)

Stress Test Interpretation

Finding	Interpretation	Treatment
Less than 15° laxity, firm endpoint	Grade I (Strain)	Splint
15-30° laxity, endpoint present	Grade II (Partial)	Cast 4-6 weeks
Greater than 30° or no endpoint	Grade III (Complete)	Consider surgery

Investigations

Imaging Assessment

Plain Radiographs:

AP, lateral, oblique of thumb
Look for avulsion fracture at proximal phalanx base
Assess for subluxation or dislocation
ALWAYS before stress testing

Stress Radiographs:

Valgus stress views
Compare to normal side
Can quantify degree of laxity

MRI/Ultrasound:

Confirm Stener lesion
Assess ligament integrity
MRI sensitivity greater than 90% for Stener

Imaging Options

Modality	When to Use	Key Finding
X-ray	All cases (first)	Avulsion fracture
Stress X-ray	Quantify laxity	Degree of opening
MRI	Suspected Stener	Ligament position
Ultrasound	Cost-effective alternative	Dynamic assessment

Management Algorithm

Surgical Management

Indications:

Stener Lesion (Palpable lump + Instability).
Complete rupture with lack of firm endpoint (greater than 30° laxity).
Displaced avulsion fracture.
Chronic instability.

Technique:

Approach: Dorsoulnar incision (S-shaped).
Identify: Superficial Radial Nerve branches (Risk!).
Stener: Find the stump superficial to adductor, incise adductor hood to reduce it back to bone.
Repair: Mitek Anchor into base of proximal phalanx.
Chronic: Tendon graft reconstruction (Palmaris Longus) or MCP Fusion (if arthritic).

MRI vs Clinical Exam

Miller RJ, et al. • J Hand Surg Am (2008)

Key Findings:

Clinical stress testing has high sensitivity for complete tears (94%)
However, differentiating Stener lesion clinically (palpable lump) is difficult
MRI Sensitivity/Specificity for Stener lesion is greater than 90%
Ultrasound is operator dependent but cost-effective (88% sensitivity)

Clinical Implication: If clinical exam suggests complete tear (laxity), get US or MRI to look for Stener lesion.

Original Stener Lesion Description

Stener B • J Bone Joint Surg Br (1962)

Key Findings:

Classic anatomical description of UCL displacement
Torn UCL stump flips superficial to adductor aponeurosis
Aponeurosis blocks ligament-to-bone contact (interposition)
Healing impossible without surgical retrieval of ligament

Clinical Implication: Foundational study establishing why complete UCL tears with displacement require surgery.

Chronic UCL Reconstruction Outcomes

Heyman P, et al. • J Hand Surg Am (1993)

Key Findings:

Palmaris longus tendon graft for chronic UCL insufficiency
Figure-of-8 configuration through bone tunnels
80-85% good/excellent outcomes
Less predictable than acute repair

Clinical Implication: Chronic cases (greater than 6 weeks) require reconstruction; outcomes are reasonable but inferior to acute repair.

Ultrasound for Stener Lesion

Hergan K, et al. • Radiology (1995)

Key Findings:

Dynamic ultrasound assessment of UCL
88% sensitivity for Stener lesion detection
Real-time comparison to contralateral side
Cost-effective alternative to MRI

Clinical Implication: Ultrasound is a valid alternative to MRI for Stener lesion detection in experienced hands.

Complications

Complications of UCL Injury

Complications

Potential Complications

Missed Stener Lesion:

Most important complication
Leads to chronic instability
Weak pinch grip, pain
Requires reconstruction or fusion

Surgical Complications:

Radial sensory nerve injury (neuroma)
Stiffness
Re-rupture
Anchor failure

Complications and Management

Complication	Cause	Treatment
Chronic instability	Missed Stener lesion	Reconstruction or fusion
Neuroma (RSN)	Surgical dissection	Desensitisation, excision
Stiffness	Prolonged immobilisation	Hand therapy
MCP arthritis	Chronic instability	Fusion if severe

Postoperative Care

Rehabilitation Protocol

Immobilisation Phase (0-6 weeks):

Thumb spica cast or splint
Include IP joint initially
Elevate to reduce swelling
Active finger ROM

Mobilisation Phase (6-10 weeks):

Transition to removable splint
Active ROM exercises
Hand therapy referral
Avoid stress on repair

Strengthening Phase (10-12 weeks):

Progressive pinch strengthening
Functional activities
Return to light work

Postoperative Timeline

Time	Activity	Goal
0-6 weeks	Thumb spica, elevation	Protect repair
6-10 weeks	Active ROM, removable splint	Restore motion
10-12 weeks	Strengthening	Functional recovery
12+ weeks	Return to sport/work	Full activity

Outcomes

Functional Outcomes

Acute Repair:

Greater than 90% good/excellent results
Stable joint, strong pinch
Return to full function expected

Conservative Treatment (appropriate cases):

Good outcomes if no Stener lesion
Risk of late instability if undertreated

Chronic Reconstruction:

80-85% satisfactory results
Less predictable than acute repair
May have some residual laxity

Outcome by Treatment

Treatment	Good/Excellent	Main Concern
Acute repair (Stener)	Greater than 90%	Stiffness
Cast (Grade I-II)	85-90%	Ensure no Stener
Chronic reconstruction	80-85%	Residual laxity
MCP fusion	Pain relief excellent	Loss of MCP motion

Evidence Base

Key Studies

Historical:

Stener (1962): Described interposition of adductor aponeurosis
Established the anatomical basis for surgical treatment

Imaging Studies:

Miller (2008): MRI sensitivity greater than 90% for Stener lesion
Clinical exam alone may miss Stener lesion

Evidence Summary

Study	Key Finding	Clinical Impact
Stener 1962	Aponeurosis blocks healing	Surgery for Stener lesion
Miller 2008	MRI greater than 90% for Stener	Get imaging if complete tear
Heyman 1993	Reconstruction techniques	Options for chronic cases

Exam Viva Scenarios

Practice these scenarios to excel in your viva examination

VIVA SCENARIOStandard

Scenario 1: Complete Acute UCL Rupture

EXAMINER

"A 30-year-old skier presents with a painful thumb after falling on his ski pole. X-ray is normal. On examination, he has tenderness over the ulnar aspect of the MCPJ and 45 degrees of valgus laxity in flexion (compared to 15 on normal side). There is no end point. How do you manage this?"

EXCEPTIONAL ANSWER

This is a **Complete Acute UCL Rupture** (Skier's Thumb). **Assessment:** - The laxity (greater than 30° and greater than 15° difference) confirms a complete tear. - The absence of end-point confirms Grade III. - **Crucial Question:** Is there a **Stener Lesion**? - Palpation: Can I feel a lump? (Proximal to joint line). - Imaging: I would request an **Ultrasound or MRI** to confirm displacement of the ligament stump relative to the adductor aponeurosis. **Management:** - **If Stener Lesion confirmed (or high suspicion):** - **Surgery:** Open Repair using a suture anchor. - Why? It will never heal because of the aponeurosis interposition. - **If No Stener (Rare for complete laxity):** - Some would trial cast, but in a young active patient with gross instability, surgery is reliable and prevents chronic instability. **Surgical Plan:** - Dorsoulnar approach. - Protect RSN. - Open adductor aponeurosis (often need to release it to find the stump). - Anatomical repair to footprint on proximal phalanx. - Thumb Spica for 6 weeks.

KEY POINTS TO SCORE

Stener lesion prevents healing

Test in flexion for PCL

Complete laxity usually mandates surgery

Protect the Radial Sensory Nerve

COMMON TRAPS

✗Stress testing before X-ray

✗Missing a minimally displaced avulsion

✗Treating a Stener lesion in a cast

LIKELY FOLLOW-UPS

"What is the anatomy of the Stener lesion?"

"How does the accessory UCL differ from the proper?"

"What are the options for a chronic injury?"

VIVA SCENARIOChallenging

Scenario 2: Diagnostic Uncertainty - Small Avulsion Fracture

EXAMINER

"A 25-year-old rugby player presents 3 days after injuring his thumb during a tackle. X-rays show a small (2mm) minimally displaced bony fragment at the ulnar base of the proximal phalanx. Clinical examination shows 25 degrees of laxity in 30 degrees flexion (15 degrees on normal side) with a soft endpoint. He asks whether he needs surgery. How would you counsel him?"

EXCEPTIONAL ANSWER

This case illustrates the challenge of small avulsion fractures with UCL instability. The clinical laxity (25 degrees, 10 degrees difference) suggests a significant injury approaching complete tear criteria, and the soft endpoint is concerning. The small bony fragment confirms injury at the UCL insertion but its small size (2mm) raises questions about whether it represents the entire ligament attachment or just a portion. My approach would be to first request further imaging - either MRI or ultrasound - to assess two critical questions: Is there a Stener lesion? How much of the UCL is still attached to bone versus avulsed? If MRI shows a Stener lesion or complete UCL disruption with the ligament substance torn off the fragment, then surgical repair is indicated. The fragment is too small to reliably fix with screws, so I would perform ligament repair with suture anchors to the proximal phalanx and excise the small fragment. If imaging shows the UCL is still substantially intact and anatomically positioned (no Stener lesion), I could consider trial of immobilization in a thumb spica cast for 6 weeks, but I would warn him that there is a risk of failure requiring surgery. In a young, active rugby player with borderline instability and a soft endpoint, I would lean toward surgical repair to ensure robust healing and prevent chronic instability which would significantly impact his grip strength and ability to play rugby safely. I would explain that surgery gives 90%+ success rate versus uncertain results with conservative treatment in this borderline case.

KEY POINTS TO SCORE

Small avulsion fragments may not capture entire UCL insertion

Soft endpoint more concerning than absolute degree measurement

MRI/US essential to determine Stener lesion and ligament integrity

Small fragments (less than 3mm) usually excised, anchor repair performed

Young athletes: low threshold for surgery to ensure robust healing

COMMON TRAPS

✗Assuming small fracture means conservative treatment is safe

✗Not considering Stener lesion despite having bony avulsion

✗Attempting ORIF of fragment too small to fix reliably

✗Not factoring patient demands (rugby) into decision

LIKELY FOLLOW-UPS

"What size avulsion fracture would you consider fixing with screws?"

"Can you have a Stener lesion with a bony avulsion?"

"What would you tell him about return to rugby after surgery?"

VIVA SCENARIOCritical

Scenario 3: Chronic UCL Instability - Reconstruction vs Fusion

EXAMINER

"A 45-year-old manual laborer presents with chronic thumb MCP instability 2 years after an untreated UCL injury. He has weakness in pinch grip affecting his work. X-rays show moderate MCP joint arthritis with joint space narrowing and osteophytes. Clinical exam shows 40 degrees of valgus laxity with no endpoint. He is frustrated his initial injury was missed and wants definitive treatment. What are your options and what would you recommend?"

EXCEPTIONAL ANSWER

This is a challenging chronic UCL insufficiency with established secondary MCP arthritis. The patient has missed the window for primary repair, and the arthritis complicates reconstruction options. My management options are UCL reconstruction with tendon graft versus MCP arthrodesis. For UCL reconstruction, I would use palmaris longus autograft (or gracilis/plantaris if PL absent) in a figure-of-8 configuration drilling tunnels through the proximal phalanx and metacarpal to recreate the proper and accessory collateral ligaments. However, in the presence of moderate arthritis, reconstruction may not relieve his pain and the graft may stretch over time with ongoing degeneration. For MCP arthrodesis, I would fuse the joint in 15-20 degrees of flexion which provides excellent pinch strength and eliminates pain. The disadvantage is loss of MCP motion, but functionally the IP joint compensates well for most tasks. Given his manual work requiring strong, reliable pinch, moderate arthritis on X-ray, and the uncertain durability of reconstruction in an arthritic joint, I would recommend MCP arthrodesis. I would explain this gives him definitive pain relief and robust stability for his manual work, with the IP joint providing adequate thumb motion for most activities. Reconstruction is an option if he strongly prefers to preserve motion, but I would set realistic expectations about likely progression of arthritis and possible need for fusion later. I would also discuss that the 2-year delay and established arthritis mean neither option will give him a completely normal thumb, but fusion provides the most predictable pain relief and functional stability for his occupation.

KEY POINTS TO SCORE

Chronic UCL injury (greater than 6 weeks): Primary repair not possible, need reconstruction

Palmaris longus graft figure-of-8 reconstruction technique

Established MCP arthritis makes reconstruction less predictable

MCP fusion (15-20° flexion) gives excellent pinch strength, definitive pain relief

Manual laborers: Consider fusion over reconstruction for durability

COMMON TRAPS

✗Attempting primary repair in chronic case (will fail)

✗Not assessing for MCP arthritis before planning reconstruction

✗Recommending reconstruction without counseling about uncertain durability with arthritis

✗Not discussing arthrodesis as viable option for manual laborer

LIKELY FOLLOW-UPS

"What are the technical steps of tendon graft UCL reconstruction?"

"What is the optimal fusion angle for thumb MCP arthrodesis?"

"Could you offer him joint replacement instead of fusion?"

MCQ Practice Points

Exam Pearl

Q: What is the difference between gamekeeper's thumb and skier's thumb?

A: Gamekeeper's thumb: Chronic attritional injury to the ulnar collateral ligament (UCL) of thumb MCP joint, originally described in Scottish gamekeepers who killed rabbits by neck wringing. Skier's thumb: Acute UCL injury from forced thumb abduction/hyperextension (e.g., ski pole strap, ball handling). Both involve the UCL proper and accessory UCL. The clinical presentation and treatment principles are similar; The distinction is historical/mechanism-based.

Exam Pearl

Q: What is a Stener lesion and why is it clinically important?

A: Stener lesion: Displaced UCL rupture where the torn ligament end lies superficial to (on top of) the adductor pollicis aponeurosis, preventing healing to bone. Occurs in complete UCL ruptures - the aponeurosis interposes between the ligament and its insertion. Clinical importance: Stener lesions cannot heal with conservative treatment as the ligament cannot reattach to bone. Requires surgical repair. Present in approximately 80% of complete UCL ruptures. Diagnosed by palpable mass at MCP ulnar aspect or MRI.

Exam Pearl

Q: How do you clinically assess UCL integrity and what constitutes instability?

A: Stress testing: Apply valgus stress to thumb MCP in 30° flexion (tests UCL proper) and full extension (tests accessory UCL). Compare to uninjured side. Instability criteria: Greater than 30° of radial deviation or greater than 15° difference from uninjured side indicates complete rupture. Endpoint: Absent firm endpoint suggests complete tear. Test with local anesthesia if pain limits examination. Caution: Excessive stress may convert partial to complete tear or displace Stener lesion.

Exam Pearl

Q: What imaging is recommended for suspected UCL injury?

A: Radiographs: AP, lateral, oblique views. Look for: Avulsion fracture at proximal phalanx base (may be rotated/displaced); Joint subluxation. Stress radiographs: Valgus stress views comparing both thumbs (under anesthesia if needed). MRI: Gold standard for soft tissue assessment; Identifies Stener lesion, ligament tears, associated injuries. Ultrasound: Operator-dependent but can assess ligament continuity and Stener lesion dynamically. Imaging helps determine surgical vs. conservative treatment.

Exam Pearl

Q: What is the treatment algorithm for UCL injuries?

A: Partial tears / Stable (less than 30° deviation): Thumb spica cast/splint 4-6 weeks, then progressive ROM. Complete tears without Stener lesion: May trial immobilization but high failure rate; Often proceed to repair. Complete tears with Stener lesion: Surgical repair required - direct ligament repair with suture anchors; Avulsion fractures fixed if large enough. Chronic injuries: Ligament reconstruction (palmaris longus tendon graft) if direct repair not possible. Post-op: Immobilization 4-6 weeks, then therapy.

Australian Context

Australian Healthcare Considerations

Medicare (MBS) Item Numbers:

47924: Ligament repair of finger joint
47927: Ligament reconstruction with graft
Hand surgery items require appropriate credentials

Setting:

Most UCL repairs performed as day surgery
Hand therapy widely available
Private health funds cover hand surgery

Australian Pathway

Presentation	Setting	Management
Acute Grade I-II	ED/Fracture clinic	Splint, follow-up
Complete tear/Stener	Day surgery	UCL repair with anchor
Chronic instability	Elective surgery	Reconstruction or fusion

UCL Injury Quick Reference

High-Yield Exam Summary

Anatomy

•Proper UCL: Flexion stabiliser
•Accessory UCL: Extension stabiliser
•Stener: Stump superficial to adductor

Testing Criteria

•Greater than 30 degrees laxity
•Greater than 15 degrees difference side-to-side
•No end point

Management Rules

•Partial: Cast 6w
•Complete/Stener: Surgery
•Fx non-displaced: Cast
•Fx displaced: Surgery

References

Stener B. Displacement of the ruptured ulnar collateral ligament of the metacarpo-phalangeal joint of the thumb. JBJS Br. 1962.
Heyman P, et al. Ulnar collateral ligament reconstruction of the thumb in the chronic setting. J Hand Surg Am. 1993.

Gamekeeper's Thumb

High Yield Overview