Table 2.

Trigger thumb, trigger finger, and clasped thumb: key clinical features, diagnostic pearls, and best treatment option.

	Key Clinical Features	Diagnostic Pearls	Best Treatment Option
Trigger Thumb	-Thumb locked in flexion at the IP joint -Hyperextension of the MCP joint -Notta’s nodule	-Clinical diagnosis (no diagnostic tests are required) - Do not confuse it with the clasped thumb. Look at the MCP joint ؞ MCP joint is not flexed ؞ Active extension of the MCP joint is preserved	Open Surgery
Trigger Finger	-Snapping and triggering of the finger -Painless clicking with digital manipulation	-Can affect multiple fingers—evaluate both hands - Underlying disease in 29% ؞ MPS, diabetes, JIA ؞ If MPS is suspected, urine should be screened for GAG, and if positive, referred for genetic evaluation	Open Surgery
Clasped Thumb	-Flexion-adduction deformity of the thumb with a fulcrum at MCP joint -Abnormal thumb extensor mechanism -Possible association with other hand disorders (syndactyly, camptodactyly, joint stiffness or ligamentous instability)	- Associated syndromes in 68% of patients ؞ Freeman–Sheldon, Emery–Nelson, Moebius, Waardenburg, congenital contractural arachnodactyly, digitotalar dysmorphism, arthrogryposis, multiple pterygium	Mild Deformity ؞Splinting Moderate/Severe Deformity ؞Surgery

GAG: glycosamynoglycans; IP: interphalangeal; JIA: juvenile idiopathic arthritis; MCP: metacarpophalangeal; MPS: mucopolysaccharidosis.