title: Type III-A hypoplastic thumb.
abstract: Thirteen type III-A hypoplastic thumbs were reviewed. The abnormalities included those found in type II hypoplasia (narrow thumb-index web space, hypoplastic thenar muscles, unstable metacarpophalangeal joint, as well as extrinsic tendon abnormalities); all had stable carpometacarpal joints. They are differentiated from type III-B hypoplastic thumbs, which have an unstable carpometacarpal joint due to a deficient base of the metacarpal. The extrinsic tendon abnormalities included absent extensor pollicis longus tendon, absent or aberrant flexor pollicis longus tendon, and a tendon interconnection between the flexor pollicis longus and extensor aponeurosis. Twelve of the thumbs had surgical reconstruction. None was treated with ablation and index pollicization.
authors.affiliation: St. Louis Shriners Hospital for Crippled Children, MO, USA.
authors.forename: P R
authors.initials: PR
authors.lastname: Manske
authors.forename: H R
authors.initials: HR
authors.lastname: McCarroll
authors.forename: M
authors.initials: M
authors.lastname: James
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002965:Classification; D006801:Humans; D007223:Infant; D008722:Methods; D009132:Muscles / Q000002:abnormalities / Q000601:surgery; D013710:Tendons / Q000002:abnormalities / Q000601:surgery; D013933:Thumb / Q000002:abnormalities* / Q000601:surgery*