What causes thumb pain radiating to the wrist?

Thumb Pain Radiating to Wrist: Differential Diagnosis and Workup

The most common causes of thumb pain radiating to the wrist are de Quervain tenosynovitis, carpometacarpal (CMC) joint arthritis of the thumb, and less commonly scaphoid or distal radius fractures, with the diagnostic approach beginning with three-view wrist radiographs followed by targeted clinical examination. 1, 2, 3

Primary Diagnostic Considerations

De Quervain Tenosynovitis

• This is the most likely diagnosis for radial-sided thumb-to-wrist pain, particularly in postpartum women and those with frequent mobile phone use. 2, 4
• The condition involves swelling of the first dorsal extensor compartment tendons (abductor pollicis longus and extensor pollicis brevis) at the wrist. 2, 4
• Peak incidence occurs between ages 40-59 years, with higher prevalence in women. 2
• The Finkelstein test is considered pathognomonic, but must be differentiated from thumb CMC arthritis. 4, 3
• Repetitive thumb movements and forceful thumb pressures are common occupational triggers. 5

Thumb Carpometacarpal Joint Arthritis

• Affects approximately 33% of postmenopausal women based on radiographic evidence, with 20% requiring treatment for pain and disability. 2
• Pain typically localizes to the base of the thumb but can radiate proximally to the wrist. 2
• The grind test helps differentiate this from de Quervain tenosynovitis—a positive grind test suggests CMC arthritis. 3

Occult Fractures

• Distal radius and scaphoid fractures can be radiographically occult in up to 30% of cases initially and must be excluded. 1, 3
• The radial styloid location with dorsal hand involvement strongly suggests distal radius or scaphoid involvement. 1
• Scaphoid fractures are the most commonly fractured carpal bone following falls onto an outstretched hand. 3

Initial Imaging Algorithm

First-Line Imaging

• Obtain three-view wrist radiographs immediately (posteroanterior, lateral, and 45-degree semipronated oblique). 6, 1
• Two-view radiography alone is inadequate for detecting wrist fractures and should never be relied upon. 6, 1
• Standard radiographic examination should include neutral position and rotation, often supplemented by oblique views. 6, 7

If Initial Radiographs Are Negative

• For suspected occult fracture with high clinical suspicion: repeat radiographs at 10-14 days or proceed directly to MRI without IV contrast. 6, 1, 3
• Specialized scaphoid views (posteroanterior in ulnar deviation, pronated oblique) can improve sensitivity for scaphoid fractures. 3
• For suspected soft tissue pathology (tendinopathy, ligament injury): MRI without IV contrast is the appropriate next study. 6, 1

Advanced Imaging Considerations

MRI Indications

• MRI without IV contrast is usually appropriate when radiographs are normal or equivocal in patients with radial-sided pain. 6
• MRI is accurate for diagnosing scapholunate ligament tears, which commonly present with radial-sided wrist pain and dorsal swelling. 6, 1
• Ultrasound can identify ganglion cysts arising from the scapholunate ligament that cause radial-sided pain. 6, 1

CT Indications

• CT without IV contrast is useful to exclude or confirm suspected wrist fractures when radiographs are equivocal. 6
• CT provides superior detail of bone cortex and trabeculae compared to MRI but has lower sensitivity for soft-tissue injuries. 6

Critical Clinical Pitfalls

De Quervain Tenosynovitis

• Failure to identify an intercompartmental septum preoperatively may lead to surgical failure, as the extensor pollicis brevis may have a separate compartment. 1, 4
• The abductor pollicis longus has multiple slips that should not be confused with the extensor pollicis brevis. 4
• Avoid injury to the sensory branch of the radial nerve during examination or intervention. 4

Fracture Evaluation

• Do not dismiss the possibility of occult fracture based on initial negative radiographs alone—up to 30% of scaphoid fractures are initially radiographically occult. 1, 3
• Conventional radiography alone can miss scaphoid fractures; specialized views and repeat imaging improve sensitivity. 3

Differential Diagnosis

• Always differentiate de Quervain tenosynovitis from thumb CMC arthritis using both Finkelstein test (positive in de Quervain) and grind test (positive in CMC arthritis). 4, 3
• Consider carpal tunnel syndrome in the differential, though this typically presents with numbness and tingling in the thumb, index, middle, and radial ring fingers rather than pain radiating from thumb to wrist. 2, 8

Treatment Implications

Conservative Management

• Steroid injection combined with immobilization relieves symptoms in approximately 72% of de Quervain tenosynovitis patients. 2
• Splinting or steroid injection may temporarily relieve symptoms in various wrist conditions. 2

Surgical Considerations

• Patients with recurrent symptoms after conservative treatment may benefit from surgical release of the first dorsal extensor compartment (de Quervain) or carpal tunnel release. 2
• For thumb CMC arthritis unresponsive to conservative treatments, surgery may be appropriate. 2