Humeroradioulnar synostosis in a patient with lambdoid synostosis

Post-traumatic humero-ulnar synostosis

A humero-ulnar synostosis is a bony connection between the humerus and the ulna. This is a very rare finding and it results in a serious disability of the elbow. Usually, a synostosis of the elbow occurs as a congenital anomaly. In this case, a 6-year-old girl was seen with a post-traumatic humero-ulnar synostosis, which has never been reported in the literature before. Surgical resection of the humero-ulnar synostosis was performed. Along with rapid intensive physical therapy, almost full recovery of function was achieved. The short-term result is very satisfactory, but the long-term results and recurrence rate are still unknown.

Upper-extremity phocomelia reexamined: a longitudinal dysplasia

BACKGROUND

In contrast to longitudinal deficiencies, phocomelia is considered a transverse, intercalated segmental dysplasia. Most patients demonstrate severe, but not otherwise classifiable, upper-extremity deformities, which usually cannot be placed into one of three previously described phocomelia groups. Additionally, these phocomelic extremities do not demonstrate true segmental deficits; the limb is also abnormal proximal and distal to the segmental defect. The purpose of this investigation was to present evidence that upper-extremity abnormalities in patients previously diagnosed as having phocomelia in fact represent a proximal continuum of radial or ulnar longitudinal dysplasia.

METHODS

The charts and radiographs of forty-one patients (sixty extremities) diagnosed as having upper-extremity phocomelia were reviewed retrospectively. On the basis of the findings on the radiographs, the disorders were categorized into three groups: (1) proximal radial longitudinal dysplasia, which was characterized by an absent proximal part of the humerus, a nearly normal distal part of the humerus, a completely absent radius, and a radial-sided hand dysplasia; (2) proximal ulnar longitudinal dysplasia, characterized by a short one-bone upper extremity that bifurcated distally and by severe hand abnormalities compatible with ulnar dysplasia; and (3) severe combined dysplasia, with type A characterized by an absence of the forearm segment (i.e., the radius and ulna) and type B characterized by absence of the arm and forearm (i.e., the hand attached to the thorax).

RESULTS

Twenty-nine limbs in sixteen patients could be classified as having proximal radial longitudinal dysplasia. Systemic medical conditions such as thrombocytopenia-absent radius syndrome were common in those patients, but additional musculoskeletal conditions were rare. Twenty limbs in seventeen patients could be classified as having proximal ulnar longitudinal dysplasia. Associated musculoskeletal abnormalities, such as proximal femoral focal deficiency, were common in those patients. Eleven limbs in ten patients were identified as having severe combined dysplasia, which was type A in seven of them and type B in four. Four patients with severe combined dysplasia had congenital cardiac anomalies, and four had associated musculoskeletal abnormalities. Three of the four patients with the type-B disorder had a contralateral ulnar longitudinal dysplasia.

CONCLUSIONS

We propose that cases previously classified as upper-extremity phocomelia represent a spectrum of severe longitudinal dysplasia, as none of the sixty extremities that we studied demonstrated a true intercalary deficiency. These findings have both developmental and genetic implications.

Humeroradial synostosis, ulnar aplasia and oligodactyly, with contralateral amelia, in a child with prenatal cocaine exposure

Humeral "bifurcation" due to humeroradial synostosis, and amelia are both very rare limb anomalies. We report on a Canadian. Aboriginal boy with both these limb deficiencies. The family history was unremarkable, but he was exposed prenatally to cocaine at the time of limb development. Humeroradial synostosis with ulnar aplasia has been reported by several authors. The majority of cases are unilateral. When both upper limbs arms are involved, cases with oligodactyly often have asymmetrical limb deficiencies and have all been sporadic to date. Some appear to represent cases of the femur-fibula-ulna or FFU complex. Affected individuals with normal hands usually have symmetrical defects and show an autosomal recessive pattern of inheritance. Limb deficiencies have been reported in several infants exposed prenatally to cocaine and have been inducible in animal models. Most are terminal transverse defects or deficiencies of middle digits. When more than one limb is involved, the defects are usually asymmetric. Our case appears to be one of the most severely affected children reported to date.

An aetiological classification for developmental synostoses at the elbow

Synostoses at the elbow joint are rare. The literature divides them into three groups based on the nature of bony ankylosis; the commonest are humeroradial synostoses. Approximately 150 cases have been reported. There are 29 reported cases of humeroradioulnar synostosis and five of humeroulnar synostosis. An anatomical classification was previously described for humeroradial synostoses. Due to significant phenotypic variability we believe a classification based solely on anatomical characteristics will in some cases be misleading. No classification exists for humeroradioulnar and humeroulnar synostosis. By re-examining the literature we have produced a combined classification for all elbow synostoses which more accurately predicts causes. Congenital elbow synostoses often cause little functional disability. Treatment by soft tissue release and osteotomy has been attempted, but although range of movement is initially, improved re-ossification is the norm. Investigation is more complicated and may be helped by classification which identifies syndrome association, risk of organ anomaly, and inheritance pattern.

Further report of a patient with humeroradioulnar synostosis and hydronephrosis

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