Skier's Thumb
Upper LimbOverview
Skier's thumb is an acute or chronic injury to the ulnar collateral ligament (UCL) of the thumb's metacarpophalangeal joint, typically resulting from forced abduction or hyperextension. This injury is common in skiers (from falling on an outstretched hand) and other athletes, but also occurs in non-athletes from direct trauma or repetitive stress. The severity ranges from partial ligament tears to complete rupture, with potential complications including chronic instability and loss of grip function.
Pathophysiology
The ulnar collateral ligament provides medial stability to the thumb MCP joint during pinching and gripping activities. Forced radial deviation or hyperextension of the thumb MCP joint causes tensile stress on the UCL, resulting in partial or complete ligament rupture. Acute injuries cause microtrauma, inflammation, and swelling; chronic injuries develop from repetitive microtrauma leading to ligament degeneration. In some cases, the ligament may avulse from its insertion with bone fragments (Stener lesion), preventing healing by interposition of the adductor aponeurosis.
Patient Education
Early and appropriate management of thumb injuries is crucial to prevent chronic instability and loss of grip strength; avoiding further stress while healing occurs will reduce risk of long-term complications.
Typical Presentation
Site
Medial (ulnar) aspect of the thumb metacarpophalangeal joint; pain may radiate into the thumb web space and palm
Quality
Sharp, stabbing pain at moment of injury; becomes dull, aching pain with activity; may describe clicking or clunking sensation with chronic injury
Intensity
Acute: 6-8/10; Chronic: 3-5/10; intensity increases with gripping, pinching, or forced thumb abduction
Aggravating
Gripping activities (holding objects, door handles), pinching movements, thumb extension, forced radial deviation of thumb, ball sports, contact activities
Relieving
Rest and immobilization, ice application, anti-inflammatory medication, avoiding gripping activities, thumb support or taping
Associated
Swelling and bruising over medial thumb MCP joint, loss of grip strength, loss of pinching ability (key pinch weakness), warmth and tenderness over UCL, possible deformity in chronic cases, loss of thumb opposition strength
Orthopaedic Tests
Magnetic Resonance Imaging (MRI) Correlation
Procedure
MRI of the thumb MCP joint with a small surface coil, including T2-weighted or STIR (fluid) sequences in the coronal plane.
Positive Finding
Discontinuity of the ulnar collateral ligament, an avulsion fragment, or the torn ligament end lying on top of the adductor aponeurosis (a Stener lesion).
Sensitivity / Specificity
Reference: Rashidi A, Haj-Mirzaian A, Dalili D, Fritz B, Fritz J. Evidence-based use of clinical examination, ultrasonography, and MRI for diagnosing ulnar collateral ligament tears of the metacarpophalangeal joint of the thumb: systematic review and meta-analysis. Eur Radiol. 2021;31(8):5699-5712.
Interpretation
Used when examination or ultrasound is unclear, and especially to look for a Stener lesion, which will not heal with a splint and needs surgical referral. The reference previously shown for this test could not be matched to any published paper and has been withdrawn. Pooled from a 2021 meta-analysis of thumb ulnar collateral ligament tears. Studies were small and the specificity confidence interval is wide. MRI also best separates displaced (Stener) from non-displaced tears.
Abduction Stress Test (Valgus Stress Test)
Procedure
If a fracture at the base of the proximal phalanx has not yet been excluded, X-ray first. Stabilise the thumb metacarpal and apply a radial (abduction or 'valgus') stress to the proximal phalanx with the MCP joint in about 30° of flexion, then in full extension. Compare with the uninjured thumb.
Positive Finding
Pain at the ulnar side of the MCP joint, more opening than on the other thumb, or no firm end-point.
Interpretation
Pain with a firm end-point suggests a partial injury. Marked laxity or no end-point, especially in both flexion and extension, suggests a complete tear and needs imaging and hand surgery referral. Pain can limit the test in the first days. The reference previously shown for this test could not be matched to any published paper and has been withdrawn. No accuracy figure is shown because none has yet been checked against a study.
Laxity Grading (Modified Abduction Stress Test with Measurement)
Procedure
Perform the abduction stress test in about 30° of MCP flexion and in full extension on both thumbs, and estimate or measure the angle of opening on each side.
Positive Finding
Opening clearly greater than on the uninjured thumb, or no firm end-point.
Interpretation
The side-to-side difference and whether there is a firm end-point matter more than any single angle. Complete tears need imaging and surgical referral; partial tears are usually managed in a splint. The reference previously shown for this test could not be matched to any published paper and has been withdrawn. No accuracy figure is shown because none has yet been checked against a study.
Thumb MCP Joint Flexion Test
Procedure
Ask the patient to bend the thumb MCP joint against light resistance.
Positive Finding
Pain or weakness at the thumb MCP joint.
Interpretation
A general check of pain on loading; it does not test the ulnar collateral ligament. Useful mainly for tracking recovery.
Adduction Test (Thumb-Pinch Strength)
Procedure
Measure key pinch (thumb pad against the side of the index finger) with a pinch gauge on both hands, three trials each, and record the mean.
Positive Finding
Weaker or painful pinch on the injured side.
Interpretation
Shows how much the injury limits function. Useful for tracking rehabilitation and return to sport, not for diagnosis.
Thumb Abduction ROM Test
Procedure
Measure active palmar and radial abduction of the thumb on both sides with a goniometer or ruler.
Positive Finding
Less range, or pain, on the injured side.
Interpretation
Records stiffness and pain limitation for tracking recovery. It does not test ligament integrity.
⚠ Red Flags
- •Severe loss of thumb opposition strength suggesting complete UCL rupture or adductor pollicis injury
- •Signs of vascular compromise (pallor, coldness, absent pulses distal to injury)
- •Open wound or penetrating injury suggesting need for wound management
- •Extreme swelling or compartment syndrome signs (severe pain out of proportion, pain on passive stretch)
- •Associated fracture dislocation requiring urgent orthopedic reduction
⚡ Yellow Flags
- •Frequent contact sport participation creating high reinjury risk
- •Occupational demands requiring high grip strength (tradespersons, athletes)
- •History of previous thumb injuries affecting coping mechanisms
- •Catastrophizing about loss of grip function or sports participation
- •Delayed seeking of care suggesting minimization of injury severity
- •Anxiety about chronic instability limiting social or occupational activities
Osteopathic Techniques
Region
Thumb MCP joint and surrounding soft tissues
Technique
Rationale
Gentle soft tissue mobilization to the thenar eminence, adductor pollicis, and medial capsule reduces muscle guarding, improves blood flow to promote healing, and decreases pain without stressing the healing UCL
Region
Thumb MCP joint
Technique
Rationale
Gentle, pain-free articulation of the thumb MCP in non-provocative directions (flexion/extension in neutral abduction) maintains joint mobility and proprioceptive input while protecting the UCL during healing phases
Region
Forearm and wrist
Technique
Rationale
Treatment of flexor pollicis longus and brevis, and adductor pollicis reduces compensatory tension in thumb musculature, improves circulation, and decreases referred pain patterns
Region
Cervical spine and upper thoracic spine
Technique
Rationale
Addressing cervical and thoracic dysfunction restores normal shoulder and arm positioning, reducing compensatory thumb positioning and stress during recovery
Region
Wrist and thumb web space
Technique
Rationale
Gentle muscle energy techniques to first dorsal interosseous and thenar muscles improve proprioceptive awareness, restore normal muscle balance without stressing UCL, and enhance rehabilitation outcomes
Region
Upper limb lymphatic
Technique
Rationale
Gentle lymphatic drainage from hand toward axilla reduces swelling and inflammation, accelerates tissue healing, and decreases pain in the acute and subacute phases
Rehabilitation Exercises
Thumb Flexion and Extension Pendulum
Supported Thumb Opposition Movement
Isometric Thumb Opposition (Static Hold)
Progressive Grip Strengthening with Therapy Ball
Thumb Key Pinch Against Resistance
Proprioceptive Thumb Joint Awareness (Moving Target Touching)
Wrist Neutral Position Awareness and Stabilization
Adductor Pollicis Strengthening with Thumb Scissors
Functional Fine Motor Tasks (Coin Picking, Button Manipulation)
Gentle Thumb Web Space Stretch
Sport-Specific Grip Training (Progressive Ball Toss and Catch)
Thumb Abduction and Adduction (Supinated Hand, Pain-Free Range)
Referral Criteria
- •Severe pain and swelling limiting functional use despite conservative management lasting >2 weeks
- •Clinical suspicion of complete UCL rupture (positive Lachman test at MCP joint) or Stener lesion requiring orthopedic imaging and possible surgical intervention
- •Loss of thumb opposition strength or sensation suggesting nerve injury
- •Associated intra-articular fracture or bone avulsion visible on imaging
- •Failure to improve after 4-6 weeks of conservative osteopathic care and appropriate rehabilitation
- •Need for advanced imaging (MRI or ultrasound) to determine ligament integrity and guide surgical versus conservative management decisions
- •Recurrent instability or giving way during functional activities suggesting need for specialized orthopedic assessment
- •Chronic pain and functional limitation affecting occupational or sports performance despite conservative treatment