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Triple arthrodesis, consisting of a fusion of the calcaneo-cuboid, talonavicular, and talocalcaneal joints, is used to correct deformity and replace braces. Indications depend on symptoms. For good results, patients should be at least 12 years old. A review of 25 cases shows that a varus deformity usually does not give good results, a pseudarthrosis always had a poor outcome, and patients are usually more satisfied than the surgeon with the result.

Pulsed electromagnetic fields (PEMF) are a useful means of treating cases of fracture nonunion. In 67.7% of nonunions with a disability time of at least 24 months, complete consolidation was obtained. This success rate is increased to 76.6% if we exclude nonunion, that presented contraindications for treatment with PEMF. The disability time had no effect on the success rate. Lesions of the humerus and atrophic nonunion had an unfavorable prognosis.

Direct electric currents ranging from 10 microA to 1000 microA increase ATP concentrations in the tissue and stimulate amino acid incorporation into the proteins of rat skin. The amino acid transport through the cell membrane, followed by the alpha-aminoisobutyric acid uptake, is stimulated between 100 microA and 750 microA. The stimulatory effects on ATP production and on amino acid transport, apparently mediated by different mechanisms, contribute to the final increased protein synthesizing activity. DNA metabolism followed by thymidine incorporation remains unaffected during the course of current application. The effects on AtP production can be explained by proton movements on the basis of the chemiosmotic theory of Mitchell, while the transport functions are controlled by modification in the electrical gradients across the membranes.

The relative strength and the failure mode of internal fixation by multiple pinning and nailing was investigated on 35 specimens. Internal fixation consisted of 3, 5 and 7 Knowles pins, a Smith-Petersen nail or a sliding nail plate. The strength of a specimen with a triflanged nail is only half of that with multiple Knowles pins. There is no significant difference in strength of 3, 5, or 7 pin specimens. The strength of an internal fixation with a sliding nail plate is not superior to the strength of multiple pinning. The mode of failure for the different types of internal fixation is primarily a crush fracture of the supporting trabecular bone at the femoral neck with downward and outward migration of the pins or nail. Except with the fixation with 3 pins where an initial bending could be observed, failure is not a plastic deformation of the internal fixation device.

A jumper's knee is an overload lesion of patellar or quadriceps tendon near its insertion at the lower or upper pole of the patella. If conservative treatment fails, an operation can be performed in Phase 3 where disabling symptoms, are present. The necrotic tissue in the patellar tendon is excised. The early results of this surgery are encouraging.