Thumb-in-palm deformity with bowstringing;
an unusual case
Nicoline de Haas-Appeldoorn
Received: 6 June 2011 / Accepted: 4 January 2012 /Published online: 13 April 2012
Abstract A spastic thumb can be abusively interpreted
as a congenital trigger thumb. This case report describes
the rare presentation of bowstringing in a spastic patient
after earlier release of the first annular pulley. It is
important to recognize bowstringing because of thera-
Level of Evidence: Level V, diagnostic study.
Keywords Spastic hand
Deformities of the spastic hand constitute one of the most
essential problems in patients with spastic hemiplegia. The
clinical picture is variableandtheoutcomeofsurgical
intervention is not predictable. There is no consensus on
the selection criteria for eligibility for surgical treatment and
no consensus on the surgical treatment of thumb-in-palm
deformity . The frequently impaired intellectual ability of
patients makes the problem even more complex. In a spastic
hand, the basic deformities are forearm pronation, flexion
of the wrist, ulnar deviation, clenched fist, or swan-neck
deformities of the fingers and a thumb-in-palm deformity.
This case report describes the rare presentation of bow-
stringing in a spastic patient after earlier release of the
first annular (A1) pulley.
An 11-year-old boy with left-sided spastic hemiplegia
caused by infantile encephalopathy presented with a
thumb-in-palm deformity on the left side. At the age of
12 months, the A1 pulley of the left thumb had been released
because of a suspected trigger thumb. No perioperative
problems were recorded. In retrospect however, it appears the
spastic thumb-in-palm deformity was abusively interpreted as
congenital trigger thumb.
The current problem consisted of a progressive, reducible,
thumb-in-palm deformity in a functional left arm, for which
normally an extensor pollicis longus rerouting was required.
Furthermore, at physical examination, there was a Zancolli 2a
deformity with bowstringing at the site of the first metacarpo-
phalangeal joint (Fig. 1). The bowstringing could, of course,
not be explained by spasticity. Apparently, bowstringing devel-
oped in the absence of the A1 pulley together with the spastic
thumb contracture. It was decided to perform correction of
the bowstringing first, as a functional pulley system is
necessary to get a functional outcome. The A1 pulley
was reconstructed using a double-loop palmaris longus
autograft (Figs. 2 and 3). One year postoperatively, grip had
subjectively and objectively increased as measured by Pinch
Gauges’ dynamometer and the Assisting Hand Assessment.
However, a nonprogressive functional-limiting extension
deficit of the first metacarpophalangeal joint of 20° per-
sisted, due to a spastic component. An extensor pollicis lon-
gus rerouting will therefore be performed.
In the thumb-in-palm deformity the flexion–adduction
contracture of the thumb results from an imbalance between
N. de Haas-Appeldoorn (*)
Department of Plastic, Reconstructive and Hand Surgery,
P.O. box 10400, 8000 GK Zwolle, The Netherlands
Eur J Plast Surg (2013) 36:267–269