Carpometacarpal Arthritis

Other Names

• Basilar Thumb Arthritis
• CMCJ Arthritis

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Background

• This page refers to degenerative arthritis of the Carpometacarpal Joint

Epidemiology

• Very common, affecting up 11% of men and 33% of women
• Second most common arthritis of hand behind DIPJ

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Pathophysiology

• Main: Osteoarthritis
• Anatomy
  • Biconcave-convex saddle joint
  • Articulation of 1st Metacarpal and Trapezium
  • There are also lesser articulations with Trapezoid, Scaphoid
• Motion: adduction-abduction, flexion-extension and axial rotation
• Pathophysiology
  • Laxity of the anterior oblique ligament or "beak" ligament leads to increased stress on CMCJ
  • Subsequently, cartilage loss, bony impingement and pain

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Risk Factors

• Men in 50s, Women in 60s
• Caucasions
• Ehler-Danlos syndrome
• Increased BMI

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Differential Diagnosis

• Fractures
  • Phalanx Fractures (Hand)
  • Metacarpal Fractures
    • Boxer's Fracture
    • Rolando Fracture
    • Bennett Fracture
• Dislocations
  • Metacarpophalangeal Joint Dislocation
  • Proximal Interphalangeal Joint Dislocation
  • Distal Interphalangeal Joint Dislocation
  • Carpometacarpal Joint Dislocation
• Tendinopathies
  • Extensor Tendon Injuries (Hand)
  • Central Slip Extensor Tendon Injury
  • Flexor Tendon Injuries (Hand)
  • Boutonniere Deformity
  • Swan Neck Deformity
  • Jersey Finger
  • Mallet Finger
  • Trigger Finger
  • De Quervains Tenosynovitis
  • Volar Plate Avulsion Injury
  • Sagittal Band Injury
• Ligament Injuries
  • Gamekeepers Thumb (UCL)
  • Radial Collateral Ligament of the Thumb Injury (RCL)
• Neuropathies
  • Wartenbergs Syndrome
  • Carpal Tunnel Syndrome
  • Guyon Canal Syndrome
• Arthropathies
  • Carpometacarpal Arthritis
  • Finger Arthritis
  • Rheumatoid Arthritis
• Nail Bed Injuries
  • Nail Bed Lacerations
  • Nail Bed Avulsions
  • Subungual Hematoma
  • Paronychia
  • Felon
• Pediatric Considerations
  • Proximal Phalanx Avulsion Fracture (Thumb)
  • Middle and Distal Phalanx Avulsion Fracture
• Other
  • Dupuytrens Contracture

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Clinical Features

• General: Physical Examination Hand
• History
  • Patients report pain, laxity and weakness
  • Trouble with pinching or grasping
• Physical Exam
  • Swelling, crepitus
  • Thumb CMC Grind Test typically positive, involves axial load and circumduction

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Evaluation

Wrist XR demonstrating severe carpometacarpal osteoarthritis of the thumb

Ultrasound guided CMC injection

Radiographs

• Standard Radiographs Hand or Standard Radiographs Wrist
• Typically sufficient to make diagnosis
• Roberts View

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Classification

Eaton and Littler Classification

• Stage I: Normal articular cartilage, possible joint widening due laxity of the beak ligament.
• Stage II: Narrowing of the joint space, debris and osteophytes smaller than 2 mm in size, more than one-third subluxation of the metacarpal.
• Stage III: Exhibits more severe joint narrowing, osteophytes and debris greater than 2 mm in size.
• Stage IV: Involvement of the scaphotrapezial joint

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Management

Nonoperative

• Goal is to relieve pain, restore joint stability
• Activity modification
• Splints
• NSAIDS
• Carpometacarpal Joint Injection
  • Eaton Stage I: 80% of individuals with relief at 18 months following CSI
  • Eaton Stage IV: Only 25% have relief at 18 months

Operative

• Indicated when conservative measures fail
• The greater the Eaton Stage, the more likely they will need surgergy
• Surgical options
  • Arthroscopy
  • 1st Metacarpal osteotomy
  • Implant and spacers
  • Ligament reconstruction
  • Arthrodesis
  • Arthroplasty

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Return to Play

• Not commonly seen in athletes

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Complications

• MCP Hyperextension deformity

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See Also

• Hand and Wrist Anatomy (Main)
• Finger Pain (Main)
• Hand Pain (Main)

External

• Sports Med Review Hand Pain: https://www.sportsmedreview.com/by-joint/hand/

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