A broad sample of extant turtles possesses a series of paired bones in the neck that are situated between the cervical vertebrae. These paired bones were originally proposed to be cervical rib remnants, but have more recently been interpreted as vestiges of intercentra. Here, we document, for the first time, the neck development of a pleurodire turtle, Emydura subglobosa, and identify blastemat...

Controversy surrounds the aetiology of obstetric brachial plexus lesions. Most authors consider that it is caused by traction or compression of the brachial plexus during delivery. Some patients, however, present without a history of major traction during delivery, and some delivered by Caesarean section also suffer the injury. In our series of 42 infants, 28 had an Erb's palsy, and the remaini...

We present here the case of a 12-year-old boy who had Klippel-Feil syndrome with renal, cardiac and multiple skeletal anomalies, and we show the relevent three-dimensional computed tomography images. Our patient had a triple renal pelvis, mitral valve prolapsus, multiple cervical vertebrae fusions, cervical ribs, hypoplasia of the right thumb, spina bifida of L5, lumbalization at the right side...

Why do all mammals, except for sloths and manatees, have exactly seven cervical vertebrae? In other vertebrates and other regions, the vertebral number varies considerably. We investigated whether natural selection constrains the number of cervical vertebrae in humans. To this end, we determined the incidence of cervical ribs and other homeotic vertebral changes in radiographs of deceased human...

The thoracic outlet syndrome occurs when the neurovascular structures are compressed as they traverse the thoracic outlet. Degenerative changes can occur in the subclavian artery and the vessel may become a source of embolism with the risk of acute or chronic upper limb ischaemia. Rarely, distal thromboembolism in the thoracic outlet syndrome may be associated with retrograde flow when there is...