Compression was evaluated in an intramedullary hindfoot arthrodesis cadaver model using an external fixator and a "second generation" intramedullary compression nail. Four cadaver specimens were used. Four trials were done with each specimen. Trial 1: manual compression with the 1st generation nail. Trial 2: external fixator for compression with the 1st generation nail. Trial 3: external fixator for compression with the 2nd generation nail. Trial 4: nail-mounted compression device with the 2nd generation nail. In Trial 1 it was not possible to obtain or maintain compression. In Trial 2 large values of compression were obtained with the external fixator, however compression was not maintained after the first generation nails were locked and the fixator was removed. In Trial 3 large values of compression were obtained with the external fixator, but minimal compression was maintained after the second-generation nails were locked and the fixator was removed. In Trial 4 large values of compression were obtained with the compression device and greater than 60% of the compression was maintained after the nail was locked and the compression device was released. The study revealed that both the external fixator and the compression device could produce compression. The external fixator is useful as an aid in the O.R. However, in this study significant compression was maintained only with utilization of the compression device.

Twenty-four patients with distal tibial growth disturbance were reviewed. Disturbances were classified as physeal bar (prior to deformity), angular, linear or combined deformities. Treatment consisted of osteotomy in fourteen, epiphyseodesis in seven, excision of bony bar in two, and observation in one patient. Follow up was an average 36.6 months (range 4-129 months) after treatment of growth disturbance. The age at time of injury was 10.4 years of age average (range 3-15 years). There were 12 SH2, 2 SH3, 7 SH4, and 3 SH5 distal tibial physeal fractures. Thirteen of 15 fractures considered high energy and only 1 of 9 fractures considered low energy resulted in angular deformity. Angular and linear deformities presented an average 46 months (range 12-120 months) and physeal bars at an average 14 months (range 6-25 months) after injury. Patients with a delay in presentation of growth disturbance greater than 24 months had angular deformities in 92% compared with 33% in children presenting less than or at 24 months. Treatment based on type of deformity, age at time of injury, and growth remaining was considered successful in 83%. Patients with angular or linear deformities were more likely to present late, have high energy injuries, be male patients and have Salter-Harris types IV and V. Early diagnosis and treatment of growth disturbance can prevent severe deformity.

A simple method was investigated to measure compartment pressures using 16-ga intravenous catheters with or without side ports attached by arterial line tubing to a pressure transducer. Pressure measurements from the experimental catheters were within 4 mm Hg of the slit catheter for 99% of all readings, and pressure measurements from the Stryker device were within 5 mm Hg of the slit catheter for 95% of all readings. The addition of one or two side ports to the experimental catheters did not alter the pressure readings. This method is comparable in accuracy to the slit catheter and in simplicity to the Stryker device.

No abstract

Unilateral femoral angulation is uncommon. We describe two children with unilateral progressive distal femoral varus and limb-length discrepancy. These deformities were associated with a fibrous lesion involving the medial aspect of the distal femoral metaphysis. Both patients were 15 to 16 months old. In both, the deformity was progressive, resulting in excisional biopsy and osteotomy. The gross and microscopic appearance of both lesions was similar, and the histology was dense fibrous connective tissue. The patients' femoral alignment was maintained at follow-up of a minimum of 16-36 months. The etiology of these lesions is unknown; they are associated with progressive deformity and appear to respond well to surgical intervention.