Thumb Ligament Injuries

By admin On Mar 13, 2024

Ovid: 5-Minute Orthopaedic Consult

Editors: Frassica, Frank J.; Sponseller, Paul D.; Wilckens, John H.

Title: 5-Minute Orthopaedic Consult, 2nd Edition

> Table of Contents > Thumb Ligament Injuries

Thumb Ligament Injuries

Dawn M. LaPorte MD

Darryl B. Thomas MD

Basics

Description

Thumb ligament injuries most commonly
involve an incomplete or complete rupture of the UCL resulting from a
forced radial deviation (abduction).
The RCL also can be injured, but it occurs less commonly.
Thumb ligament injuries occur in males and females of all ages.
Classification:
- These injuries are complete or incomplete, based on the integrity of the ligament and its bony insertion.
Synonyms: Gamekeeper’s thumb; Skier’s thumb

General Prevention

Prevention involves knowing the mechanism associated with this injury.

Epidemiology

Incidence

These injuries occur most commonly in skiers and ball-handling athletes.

Risk Factors

Skiing accidents involving ski poles or falls
Athletic activities involving ball handling, such as baseball, football, or basketball

Etiology

Forced radial deviation (abduction) of the thumb is the cause.

Associated Conditions

Avulsion fracture of the tendon insertion
Capsular injuries or Stener lesions:
- Complete rupture of the UCL with the
  adductor aponeurosis interposed between the distally avulsed ligament
  and its insertion into the base of the proximal phalanx
- Important to recognize but not always readily apparent

Diagnosis

Signs and Symptoms

Pain
Swelling
Weakness
Deformity localized to the ulnar base of the thumb
Loss of pinch function

Physical Exam

Ulnar swelling, weakness, or a local palpable mass from a rolled avulsed ligament or bone fragment may be present.
The examiner often can radially deviate
the patient’s thumb passively to a marked angle, as compared with the
opposite, uninjured thumb.
- Absence of an “endpoint” to joint opening is diagnostic.
- Radiographs should be reviewed before
  testing for joint stability to assess for a fracture (so as not to
  displace a fracture if present).
Often a digital block is necessary to complete a full examination because of pain and swelling in the acute setting.
Surgical repair often is necessary in the presence of joint opening.

Tests

Imaging

Acute injuries:
- Plain films are necessary to rule out fracture.
- Stress testing usually is not needed.
Chronic injuries:
- Radiographs should be obtained to assess for degenerative changes.
- Stress radiographs may be helpful.

Pathological Findings

Attenuation or rupture of the UCL of the thumb is noted.

Differential Diagnosis

1st metacarpal or proximal phalanx fractures
1st CMC joint arthritis
Volar plate injury

Treatment

General Measures

A thumb spica splint or cast
immobilization is indicated for 4 weeks for a partial rupture, or up to
6 weeks if an associated avulsion fracture is present (1).
For acute injury:
- Rest, elevation, ice
- Immobilization in a thumb spica splint
- Analgesics
- Orthopaedic follow-up
For chronic injury:
- Thumb spica brace
- Activity modification
- Orthopaedic surgery consultation for elective ligament repair/reconstruction

Special Therapy

Physical Therapy

Physical therapy is helpful postoperatively to increase ROM and strength and to assist in resuming activities.

Medication

Commonly, proper rest is all that is
needed for restoration of function, although pain and swelling may
persist for several weeks.

Surgery

Surgical treatment in the acute setting is by suture repair.
For old injuries, tendon or fascial grafts may be necessary.
When crepitus or pain is present on a
grinding type of joint manipulation (development of arthritis),
arthrodesis (fusion) may provide the best result (check radiographs to
diagnose arthritis).
If the ligament rupture is complete and acute, primary repair should be performed.
When the diagnosis is delayed for ≥1 month, fibrosis makes identification and repair of the ligament more difficult.

P.453

Follow-up

Prognosis

Generally, the prognosis is good.

Complications

Chronic instability
Nonunion of avulsed fragment
Degenerative joint disease

Patient Monitoring

Monitoring is performed by the orthopaedic surgeon to assess proper restoration of function and stability.
Patients are followed at 4–8-week intervals until healing is complete, with a full ROM and restoration of strength.

References

1. Campbell JD, Feagin JA, King P, et al. Ulnar collateral ligament injury of the thumb. Treatment with glove spica cast. Am J Sports Med 1992;20:29–30.

Additional Reading

Glickel
SZ, Barron OA, Catalano LW, III. Dislocations and ligament injuries in
the digits. In: Green DP, Hotchkiss RN, Pederson WC, et al., eds. Green’s Operative Hand Surgery, 5th ed. Philadelphia: Elsevier Churchill Livingstone, 2005:343–388.

Trumble TE. Hand fractures. In: Trumble TE, ed. Principles of Hand Surgery and Therapy. Philadelphia: WB Saunders, 2000:41–89.

Miscellaneous

Codes

ICD9-CM

842.10 Thumb ligament sprain

Patient Teaching

Patients should limit activities with immobilization to
allow for healing, followed by removable splinting as needed while
activities are resumed slowly.

FAQ

Q: How is a partial UCL tear treated?

A:
Incomplete tears of the UCL are managed with immobilization of the
thumb metacarpal joint for 4 weeks in neutral varus/valgus alignment
and slight flexion. It can be immobilized with an Orthoplast splint or
a cast.

Q: How is the diagnosis of a complete UCL tear made?

A:
Physical examination is usually adequate for diagnosis. The metacarpal
joint is tested in 30° of flexion, and absence of an endpoint to joint
opening with radial stress is key to the diagnosis. Plain radiographs
should be obtained to assess for presence of an avulsion fracture, but
avulsion fracture and complete tear of the UCL can occur in the same
thumb.