Percutaneous cannulated screw coracoclavicular fixation for acute acromioclavicular dislocations.

In 1941, Bosworth introduced a new method of repairing acute complete acromioclavicular dislocations in which a noncannulated coracoclavicular lag-screw was inserted by a blind technique. The author reintroduces the percutaneous coracoclavicular fixation concept. A cannulated screw was specially designed, and the technique of percutaneous insertion under fluoroscopic image control was developed. Fifty-three acromioclavicular dislocations were treated by this method. There were 40 Type III, five Type IV, and three Type V dislocations with distal clavicle fractures in conjunction with complete coracoclavicular ligament tears. Technical failures, which occurred in 17 of 53 patients (32%) included: failed percutaneous insertion in two; early screw pullout in three; late screw pullout in four; subluxation after screw removal in six; and malreduction of Type IV dislocation in two. There was no screw breakage or evidence of migration. Serous drainage occurred in two patients.

Postdecompression lumbar instability.

In the last two decades, the concept of spinal stenosis and its treatment by surgical decompression has been widely accepted. Complications such as olisthy, disc rupture, facet fracture, and intractable back pain began to appear postoperatively, suggesting instability as their cause. A retrospective study of 344 patients treated surgically for lumbar stenosis revealed a 17% reoperation rate for complications resulting from obvious or suspected instability. Sixteen cases of postdecompression olisthy, 14 cases of fresh disc herniation, and 27 cases of intractable back pain required further surgery. Preoperative indicators of potential instability are degenerated discs as evidenced by traction spurs or diminished disc height, olisthy, and scoliosis or asymmetrically narrowed discs. Total facetectomy and pars excision at surgery destabilize the spine and must be added to the preoperative risk factors for instability. Calcified annulus, capsule and ligamentum flavum, or complete disc resorption may offer some protection from postoperative instability. The level of instability may be preselected by the proximity to the intercrestal line. It is recommended that during surgical decompression for spinal stenosis, the posterior elements be spared as much as possible to avoid instability after surgery. Factors suggesting instability noted preoperatively or decompression which produces instability suggest that fusion should be combined with decompression. Spinal fusion is the treatment for postoperative instability.

Congenital distal femoral focal deficiency: report of a unique case.

An 8-year-old Chinese boy with congenital leg length discrepancy is believed to be the first reported case of unequivocal distal femoral focal deficiency. A pseudarthrosis is present between the normal appearing distal femoral epiphysis and the lower end of the femoral diaphysis. The patient's family history is negative for congenital limb deficiency, psuedarthrosis and neurofibromatosis. There is no history of trauma or infection. Congenital lack of distal femoral physis in this case is analogous to Aitken's Classification Type B proximal femoral focal deficiency.

Embryogenesis and prenatal development of congenital vertebral anomalies and their classification.

Vertebral anomalies were studied in 144 patients. The specific anatomic defects were defined by serial roentgenograms: anterior approaches were used in 42 operations and posterior approaches in 74 operations. Growth features of the spine were examined histologically in 15 embryos and fetuses ranging in length from 6 to 120 mm. After an extensive review of the literature on normal human spine embryology and fetal development, and after defining the specific vertebral anatomic defects and their pathogenesis, some new concepts of congenital vertebral anomalies formation are proposed. Old concepts are found to be inadequate in light of our current knowledge of embryogenesis. The authors' new and all-inclusive classification of congenital vertebral anomalies is based on specific defects, pathogenesis, and time for origin in embryonic or fetal development.