Skier's Thumb

Upper Limb

Overview

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 a Stener lesion, the torn end of the UCL (with or without a small bone flake) displaces on top of the adductor aponeurosis, which then blocks it from healing.

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

Test descriptions are written with AI assistance from standard clinical texts. Where a test lists Sources, its description has been checked against them; those sources are independent and do not endorse OsteoKit. Accuracy figures and grades (A–D) appear only when checked against the published study; tests without one are marked “No accuracy study”.

Further reading: full test procedures are described in standard clinical examination texts, e.g. Magee & Manske, Orthopedic Physical Assessment (7th ed.), and Cook & Hegedus, Orthopedic Physical Examination Tests: An Evidence-Based Approach (2nd ed.).

Grade A+
A+ABCDNear-definitive: a result is close to conclusive on its own (likelihood ratio ≥20 or ≤0.05)
useful both to rule in and rule out.

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

99% (pooled, 5 studies)/100% (pooled, lower 95% CI 87%)

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.

Further reading

No accuracy study

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.

Sources

No accuracy 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.

Sources

No accuracy 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.

Sources

Performance measure

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.

Sources

No accuracy study

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.

Sources

⚠ 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

Partial tears of the thumb ulnar collateral ligament are treated with rest, ice, compression and a thumb spica splint for about 3 weeks, then therapy and strengthening, for around 6 weeks of splinting in total. Persistent weakness or pain after that is a reason for surgical referral. No trials of osteopathic techniques were found.

Safety: An avulsion fracture, or laxity of more than 30° (or 15–20° more than the other thumb), needs urgent referral to a hand surgeon. Avoid radial stress on the thumb MCP while the ligament heals.

Region

Thenar muscles and soft tissues around the thumb (no radial stress on the MCP)

Technique

Soft tissue, wrist and handNo trials found

Rationale

Soft tissue to the wrist and hand: flexor retinaculum, palmar fascia, thenar and intrinsic muscles.

How it's done, cautions & evidence

How it's done

Hands-on kneading, stroking and sustained pressure to the soft tissues of the wrist and hand: the flexor retinaculum and thenar muscles over the carpal tunnel, the first dorsal compartment, the wrist ligaments, the palmar fascia, the hand intrinsics and the finger flexor sheath at the A1 pulley. In carpal tunnel trials, soft tissue mobilisation was often combined with neural mobilisation.

Cautions

In Guyon canal syndrome, avoid prolonged pressure over the hypothenar eminence. After a fall on the hand, rule out a fracture first: scaphoid fractures are often missed on the first X-ray.

Evidence in Skier's Thumb

Searched 26 Oct 2026: no trials of soft tissue technique in thumb UCL injury.

Region

Forearm and wrist muscles

Technique

Soft tissue, elbow and forearmNo trials found

Rationale

Soft tissue to the forearm flexor and extensor muscles that move the wrist and fingers.

How it's done, cautions & evidence

How it's done

Hands-on kneading, stroking and sustained pressure to the forearm extensor and flexor muscles, their tendon origins at the epicondyles, the supinator, the pronators and the triceps. Deep transverse friction across the tendon origin is part of the Cyriax method for lateral elbow pain.

Cautions

Avoid direct pressure on an olecranon bursitis. A red, warm, tender bursa, especially with fever, may be septic and needs medical review.

Evidence in Skier's Thumb

Searched 26 Oct 2026: no trials of forearm soft tissue in thumb UCL injury.

Region

Wrist and forearm muscles

Technique

Muscle energy, elbow and forearmNo trials found

Rationale

Muscle energy technique to ease tight forearm muscles that act on the wrist (wrist extensors or flexors, pronators or supinators).

How it's done, cautions & evidence

How it's done

The wrist or forearm is taken to the barrier of the tight muscle group (wrist extensors or flexors, pronators or supinators). The patient pushes gently back, at about 10–20% effort, against resistance for 5–10 seconds, relaxes for 3–5 seconds, and the new barrier is taken up.

Cautions

Not used with an acute fracture, a joint infection or a bone malignancy; take care with severe osteoporosis or after surgery that limits muscle contraction. Use the least force needed: too much can tear a muscle or pull off a tendon, especially in older patients.

Evidence in Skier's Thumb

Searched 26 Oct 2026: no trials of forearm muscle energy technique in thumb UCL injury.

Rehabilitation Exercises

Thumb Flexion and Extension Pendulum

Range of MotionBeginner

Supported Thumb Opposition Movement

Range of MotionBeginner

Isometric Thumb Opposition (Static Hold)

StrengtheningIntermediate

Progressive Grip Strengthening with Therapy Ball

StrengtheningIntermediate

Thumb Key Pinch Against Resistance

StrengtheningIntermediate

Proprioceptive Thumb Joint Awareness (Moving Target Touching)

BalanceIntermediate

Wrist Neutral Position Awareness and Stabilization

PosturalBeginner

Adductor Pollicis Strengthening with Thumb Scissors

StrengtheningIntermediate

Functional Fine Motor Tasks (Coin Picking, Button Manipulation)

StrengtheningAdvanced

Gentle Thumb Web Space Stretch

StretchingBeginner

Sport-Specific Grip Training (Progressive Ball Toss and Catch)

StrengtheningAdvanced

Thumb Abduction and Adduction (Supinated Hand, Pain-Free Range)

Range of MotionBeginner

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