Non-vascularized toe phalanx transfer for correction of severe clinodactyly of the thumb in Rubinstein–Taybi syndrome

In Rubinstein–Taybi syndrome, patients may have a particularly severe clinodactyly of the thumb. We evaluated a new method for correction of these severe clinodactylies using non-vascularized toe phalanx transfer as a replacement for the abnormal delta phalanx. Results of the new technique are presented, together with those of an osteotomy technique. We retrospectively recorded the angle of the clinodactyly before and after surgery and at long-term follow-up of 11 osteotomies and five transfers in nine patients from 1990 to 2017. The pre-operative angle of clinodactyli was similar between the two groups with a mean of 59°. After surgery, the correction was equivalent (7° and 11°). At the last follow-up (7 and 18 years), the relapse of clinodactyly was 17° for osteotomies and 1° for phalanx transfers. We noticed growth of the transferred phalanx, resulting in an excellent thumb length. We conclude that non-vascularized toe transfer can be an effective correction of severe clinodactyly and may be more stable than osteotomy in the long-term. Level of evidence: IV

Triphalangeal thumb: clinical features and treatment

Triphalangeal thumb is a rare congenital anomaly in which the thumb has three phalanges. Clinical presentation of triphalangeal thumb can vary considerably and can be present in both hands or unilateral. The thumb can be long with a finger-like appearance. The presence of clinodactyly depends on the shape of the extra phalanx varying from wedge-shaped to rectangular. Various joints, ligaments, muscles, and tendons of the first ray can be hypoplastic or absent, with varying degrees of stiffness or instability. The aim of surgical treatment is to reconstruct or correct the anatomic anomalies to obtain greater function and a more acceptable appearance. In our series, operations varied from removal of the delta phalanx with ligament reconstruction to multiple osteotomies and rebalancing of soft tissues. Results in these often complex cases can be rewarding if the surgeon has sufficient knowledge of the underlying anatomic differences. This review summarizes our current concepts of presentation and management of the triphalangeal thumb.

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. Level of Evidence: 2

Malformations of the first ray of the foot in children: diagnosis, clinical picture, treatment

Malformations of the first ray of the foot vary widely and are divided into simple and complex. Complex malformations include abnormality of development of the first metatarsal or the main phalanx and refer to atypical adducted foot deformity. They are also characterized by varus location of the first ray of varying severity. The cause of deformation is a damage of longitudinal epiphyseal growth plate area of the first metatarsal - “longitudinal epiphyseal bracket” or the so-called delta phalanx. Over the past five years, we treated 37 patients (53 feet) aged from 6 months to 17 years old with developmental disabilities of the first ray of the foot. The spectrum of pathology is very diverse. In the majority of cases surgical treatment was multi-staged. It was revealed that the removal of deformity at the first stage of treatment should be complete, with maximum use of the bone to restore the length and shape of the affected bone. In treating combined deformities the good effect is guaranteed only with the removal of all the elements, including excision of the fibrous bridle along the inner surface of the first ray.

Long-term results following osteotomy of the thumb delta phalanx in Rubinstein–Taybi Syndrome

Rubinstein–Taybi Syndrome is a rare condition affecting 1:125,000 children. It is associated with short broad radially deviated thumbs, secondary to a delta proximal phalanx of the thumb. We undertook a retrospective review of seven children (13 thumbs) with Rubinstein–Taybi syndrome whose thumbs were treated using a corrective osteotomy to the delta phalanx over a 13 year period. The types of osteotomy used in the series were reverse wedge osteotomy, opening wedge osteotomy and dome shaped osteotomy. The mean preoperative radial deviation of thumbs was 68° (range 45–85°). At follow up five of the 13 thumbs demonstrated some residual radial deviation. All recurrences occurred in the dome shaped osteotomy group. Our data suggest that surgery is effective in correcting the deformity, but there is a risk of incomplete correction or recurrence. Despite the recurrence the mean postoperative deformity was significantly better than preoperatively and the majority of patients families subjectively reported good function. No patient in our series has yet undergone further corrective surgery.