guidebook. - Fanconi Anemia Research Fund

98
Fanconi Anemia: Guidelines for Diagnosis and Management
The early referral and assessment establish a doctorpatient
relationship with the child and family. In addition,
the evaluation and discussion answer many of the
questions that parents may have about limb differences
in respect to cause, treatment, and expectations. Parents
often seek information via the internet, which can be
a compendium of misinformation. Furthermore, many
children with upper extremity limb problems require
early therapy, which can be instituted after the initial
assessment.
Limb evaluation often occurs prior to the diagnosis of
FA. The precise indication for a chromosomal breakage
test or other diagnostic test for FA in children with limb
anomalies is still evolving. Testing every child with
isolated thumb or hand abnormalities should be considered.
We recommend a chromosomal breakage test on
all children with deficiencies of the thumb and radial
border of the forearm. Additional findings, such as
abnormal skin pigmentation (café au lait spots), growth
retardation, and microcephaly, add to the suspicion of
FA.
Table 1: Classification of Thumb Hypoplasia
Type Findings
Treatment
I Minor generalized hypoplasia Augmentation
II A. Absence of intrinsic thenar muscles
B. First web space narrowing
C. Ulnar collateral ligament
(UCL) insufficiency
III
Similar findings as Type II plus extrinsic
muscle and tendon abnormalities
Skeletal deficiency
A. Stable carpometacarpal joint
B. Unstable carpometacarpal joint
A. Opponensplasty
B. First-web release.
C. UCL reconstruction
A. Reconstruction
B. Pollicization
IV Pouce flottant or floating thumb Pollicization
V Absence Pollicization
Adapted from James et al.