Synpolydactyly of the hand: a radiographic classification.
Synpolydactyly is an uncommon congenital anomaly characterized by polydactyly with syndactyly in the central hand. The purpose of this investigation was to develop and assess the reliability of a radiographic classification system for synpolydactyly. We identified 56 hands with central synpolydactyly and developed a radiographic classification system that categorizes by the location within the hand, the bony level of polydactyly, and the presence of a delta phalanx. Four paediatric hand surgeons independently reviewed each radiograph to establish reliability. There was exact agreement among raters in 40 cases (71%). The inter-rater reliability was 0.97 and intra-rater reliability was at least 0.87. Seven of 16 bilateral cases had symmetric deformity classification. The most common presentations were types 1A and 2A. We present a new, reliable radiographic classification system for synpolydactyly that will allow improved communication between clinicians and serve as a foundation for future investigations.


METHODS
2.
Department of Orthopaedic Surgery, Shriner's Hospital for Children and St. Louis Children's Hospital at Washington University School of Medicine, St Louis, MO, USA.
L B
LB
Wall
Department of Orthopaedic Surgery, Boston Children's Hospital, Boston, MA, USA.
D S
DS
Bae
Texas Scottish Rite Hospital, Dallas, TX, USA.
S N
SN
Oishi
Department of Orthopaedic Surgery, Shriner's Hospital for Children and St. Louis Children's Hospital at Washington University School of Medicine, St Louis, MO, USA.
R P
RP
Calfee
Department of Orthopaedic Surgery, Shriner's Hospital for Children and St. Louis Children's Hospital at Washington University School of Medicine, St Louis, MO, USA goldfarbc@wudosis.wustl.edu.
C A
CA
Goldfarb
D002648:Child; D006801:Humans; D015588:Observer Variation; D011859:Radiography; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013576:Syndactyly / Q000145:classification* / Q000000981:diagnostic imaging*
Polydactyly; classification; radiograph; reliability; syndactyly