|
Year |
2002 |
|---|---|
|
Question Number |
157 |
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Category |
Pediatric Orthopaedics |
Question
A 9-month-old infant has a hypoplastic thumb. Examination reveals a narrowed thumb-index web space, hypoplasia of the intrinsic thenar muscles, and thumb carpometacarpal(CMC) and metacarpophalangeal(MP) joint instability. The thumb is radially abducted. Radiographs of the thumb show the full complement of bones, but they are hypoplastic relative to the contralateral normal thumb. Reconstruction should consist of
1- Ring sublimes opponensplasty, long sublimes flexorplasty, and extensor indicis proprius transfer for extension.
2- CMC and MP fusion in palmar abduction.
3- Abductor digiti minimi oppenensplasty, extensor indicis transfer for thumb extension, and release of the anomalous abductor pollicis brevis.
4- Thumb ablation and index pollicization
5- Vascularized second toe metatarsophalangeal joint transfer to the CMC joint and abductor digiti minimi opponensplasty.
Figures
Answer (click for answer)
Preferred Response: 4
Discussion:
In the pediatric patient with a hypoplastic or absent thumb the index finger pollicization procedure is commonly performed. Pollicization is the transfer of the index finger to the position of the thumb. This includes transfer of the whole finger with its skin, nail, bone, joints, blood vessels and nerves to the thumb position making the hand appear more natural and most importantly giving the hand much more functionality. The hand is more suitable for picking up heavier and larger objects, and improving the ability of the hand to perform more complex activities of daily living such as buttoning clothing. Outcomes of the pollicization procedure showed that the pollicized thumb has 50% motion compared to normal, 21% strength, and is able to perform 84% of the tested activities as compared to normal thumbs.
Reference: Manske PR, McCarroll HR Jr: Reconstruction of the congenitally deficient thumb. Hand Clin 1992;8:177-196
Egloff DV, Verdan C: Pollicization of the index finger for reconstruction of the congenitally hypoplastic or absent thumb. J Hand Surg Am 1983;8:839-848.