Disease Description (Causes and Symptoms)
- Name: Thumb metacarpophalangeal joint collateral ligament injury (Gamekeeper's thumb / Skier's thumb)
- Causes and pathophysiology: This is an injury in which valgus (forcing outward) and hyperextension (bending backward) forces are applied to the medial (ulnar) collateral ligament (ulnar collateral ligament, UCL) at the metacarpophalangeal joint (MCP joint) of the thumb, causing a partial or complete ligament tear. It may occur due to acute trauma (such as falling while holding a ski pole or hitting the handlebar of a bicycle) or repetitive stress. In some cases, the ligament ruptures and the retracted tissue becomes trapped beneath the skin, causing a Stener lesion that makes spontaneous healing difficult.
- Main symptoms: Pain and tenderness on the medial side of the thumb MCP joint, swelling, bruising, weakened pinching and gripping strength, and a feeling of joint instability (pain or a feeling of looseness during valgus stress). In severe injuries, pain is intense when grasping objects and pinch function is reduced.
Treatment Methods
- Initial (non-surgical) treatment
- In mild cases (partial tear, mild instability): Immobilization with a thumb-spica brace or splint for approximately 4–6 weeks, followed by rehabilitation (recovery of joint mobility and strengthening).
- Pain control: NSAIDs (e.g., ibuprofen) or analgesics, cold compresses, and rest.
- Physical therapy: Exercises to restore joint mobility, pinch strength, and control of extension and flexion.
- Surgical treatment
- In cases of complete rupture, severe joint instability, or suspected/confirmed Stener lesion, surgical repair such as suturing or tendon-ligament reconstruction is performed. Surgery is generally performed through an open procedure or an arthroscopic approach, and immobilization and rehabilitation are required for a certain period after surgery.
- Tests that help determine the diagnosis and treatment plan
- X-ray: Checks for the presence of a fracture (avulsion fracture); stress radiographs are used to assess instability.
- Ultrasound·MRI: Checks whether the ligament is torn, the location of the tear, and whether a Stener lesion is present.
- Precautions (during and after treatment)
- Resuming activities too early may cause re-tearing or chronic instability → Follow the immobilization period instructed by the doctor.
- If surgery is recommended, failure to undergo surgery at the appropriate time increases the risk of chronic instability and arthritis.
- Recovery of pinching and gripping strength through rehabilitation (physical therapy) is necessary.
Checklist Before an Outpatient Visit (Preparation and Example Questions)
- Items/materials to prepare or submit
- A list of currently taken medications (including anticoagulants and antiplatelet drugs) and allergy information
- A record of when and how the injury occurred and the pattern of symptom onset
- The severity and frequency of pain, presence of swelling or sensory abnormalities, and the degree of limitation in hand use
- Previous X-ray/MRI/ultrasound films or reports, if available
- Occupation·hobbies (frequency of hand use and whether you participate in sports), and hand dominance (dominant hand)
- Frequently asked items at an outpatient visit
- When symptoms began, factors that worsen or improve them, history of previous injuries, and whether systemic symptoms such as itching or fever are present
Examples of General Questions to Ask the Doctor
- Is this injury a complete tear or a partial tear?
- What are the criteria for needing surgery?
- What is the expected recovery period, and when can I return to daily activities (exercise, work, etc.)?
- What are the side effects of prescribed medications (e.g., NSAIDs), and what precautions should I take when taking them?
- How will rehabilitation proceed, and what exercises can I do at home?
- What is the long-term prognosis (risk of chronic instability or arthritis)?
Examples of Condition-Specific Questions
- In my case, is a Stener lesion (an isolated ligament fragment) suspected? Should it be confirmed with ultrasound or MRI?
- An avulsion fracture (bone fragment) is visible on the X-ray. In this case, does it usually heal well without surgery, or is surgery likely to be necessary?
Brief summary: Injury to the medial collateral ligament of the thumb MCP joint is important because it affects pinching function and joint stability. Depending on the symptoms and imaging findings, conservative treatment (immobilization and rehabilitation) or surgical treatment is selected. Appropriate diagnosis (especially determining whether a Stener lesion is present) and not missing the appropriate treatment timing are important for the long-term prognosis.