Transfibular compression arthrodesis of the ankle joint.

Eleven ankle arthrodeses were performed on ten patients using a transfibular technique. This technique employs a lateral approach in which the distal fibula is resected while preserving the peroneal tendon sheath, allowing excellent exposure and contouring of the tibiotalar joint. Compression is attained by using a T-plate placed across the tibiotalar joint with the aid of an AO compression apparatus.

Computerized analysis of isokinetic torque curves for muscle strengthening.

Isokinetic exercise measurements are widely used in rehabilitation medicine for evaluation and treatment planning. Computerized peak torque, work, and power measurements in isokinetic exercise can be obtained reliably when testing muscles that cross the knee and elbow joints. Important technical considerations in torque curve analysis are axis alignment, instrument calibration, and damp and gravity correction factors.

The effect of halo-vest length on stability of the cervical spine. A study in normal subjects.

In order to study how the efficiency of the halo vest is affected by different lengths of the vest, an experimental headband was devised that allowed the head of a normal person to be held securely in the halo attachment. The vest was then modified to allow it to be adjusted to three different lengths (Fig. 2): a full vest extended to the iliac crests, a short vest extended to the twelfth ribs, and a half vest extended to the level of the nipples.

Traction bow for acute reduction of fracture and/or dislocation of the thoracic or thoracolumbar spine.

Treatment of acute fractures and/or fracture dislocations of the thoracic or thoracolumbar spine has traditionally involved bedrest or the use of traction devices with external hanging weights, until surgical correction can be accomplished. A fiberglass tubular traction bow with continuous adjustable elastic tension has been designed for the application of skeletal traction. When used to treat thoracic or thoracolumbar fractures and/or dislocations, it can maintain distraction forces in an uninterrupted fashion.

Complications associated with the halo-vest. A review of 245 cases.

The cases of all patients treated with halo-vests for cervical trauma at the University of Virginia since 1977 were analyzed retrospectively. A standardized chart and radiographic review protocol were used to identify complications associated with the use of the orthosis. Two hundred and forty-five patients satisfied the criteria for inclusion in the study.

The effect of core decompression on femoral head blood flow in steroid-induced avascular necrosis of the femoral head.

Previous reports from this and other laboratories have shown that the histological changes in the femoral head that are associated with steroid treatment are consistent with avascular necrosis of the femoral head. In this experiment, we studied the effect of core decompression on femoral head blood flow in steroid-treated rabbits using the microsphere technique. The results showed that there was a gradual decline of femoral head blood flow in animals that received weekly injections of methylprednisolone without core decompression.

Semirigid rod fixation for long-bone fracture.

Experiments on 119 New Zealand rabbits were performed to measure healing strength of femurs. Four pairs of normal rabbit femurs were also studied in vitro by use of a four-point bending test to measure bending rigidity. Rabbit-sized octagonal cross-sectioned intramedullary rods with 12%, 20%, 50%, 75%, and 100% of femoral bending rigidity were specially prepared.

Comparative strength of anterior spinal fixation with bone graft or polymethylmethacrylate. Experimental operations and observations on dogs.

In 23 dogs, polymethylmethacrylate (PMMA) was safely implanted in the region of the spinal cord. The dogs were treated by bone or cement fixation after anterior excision of a single cervical vertebral body. Fixation was compared at 0-18 weeks, with control values obtained from 11 dogs.

The use of bone allograft: a survey of current practice.

A questionnaire was sent to all chairmen of American orthopedic training programs, requesting information on their use of bone allograft and banking methods. Of the 93% who responded, 55% reported using bone allograft most commonly for benign tumor defects or spine fusions. Methods of procurement, preservation, and storage varied widely.

The nonsurgical management of odontoid fractures in adults.

Twenty-five odontoid fractures that were treated nonsurgically at the University of Virginia Hospital in the last 5 years were reviewed. Motor vehicle accidents were the major cause of this injury in our series. Early recognition and firm external stabilization of Type I and Type III fractures of the odontoid resulted in union in 100% of our patients.

Safety of anterior cement fixation in the cervical spine: in vivo study of dog spine.

There is increased use of methylmethacrylate in the treatment of neoplastic lesions of the spine. The advantage of this treatment is immediate stabilization, thus avoiding prolonged immobilization. In vivo study using a dog model showed that anterior fixation with cement, with or without Gelfoam as insulation material, produced no spinal cord injury.

Femoral head blood flow in long-term steroid therapy: study of rabbit model.

Using a rabbit model, previous studies showed steroid-induced hyperlipidemia with subsequent fatty embolization of the subchondral arteries and hypertrophy of the marrow fat cells, followed by elevation of femoral head pressure from the normal level of 25 cm to nearly 60 cm H2O after eight weeks of treatment. This has led us to believe that pressure changes lead to decreased blood flow in the femoral head. In our study of 22 New Zealand white adult rabbits, weighing an average of 4.

Comparative strengths of various anterior cement fixations of the cervical spine.

In vivo study, using cadaveric dog cervical spine, was performed in which the middle segment of the vertebral body was removed producing anterior instability. Eleven various methods of stabilization utilizing polymethylmethacrylate and other fixation devices were employed, and their static strength in hyperextension was tested and compared. A portion of the same dog's cervical spine in each case was used as a control.

Steroid-induced femoral head pressure changes and their response to lipid-clearing agents.

In rabbits, cortisone increases marrow fat cell size and intrafemoral head pressure, produces systemic fatty embolization, and probably is one of the causes of avascular necrosis of the femoral head. Clofibrate, a lipid-clearing agent, decreases the serum cholesterol level, reduces the marrow fat cell size changes, and decreases intrafemoral head pressure. This might be significant in improving femoral head venous outflow in long-term steroid-treated persons.

Cortisone-induced intrafemoral head pressure change and its response to a drilling decompression method.

Intramedullary head pressure changes were studied in a group of cortisone-treated New Zealand white rabbits. In addition to femoral head pressure measurements, serum cholesterol levels were followed serially and pathologic specimens from cortisone-treated femoral heads were obtained. Surgical decompression by a drilling method was performed and pressures were remeasured at four weeks following decompression.

Variable strengths of the wire fixation.

Three groups of wires- three strands of 24 gauge stainless steel, 18 gauge Vitailium wire and 16 gauge stainless steel wire were used in this study. The results revealed the braided wire increased the strength slightly when compared to the single strand and the twisting method not only weakened the wire strength but also resulted in loss of fixation rapidly through uncoiling. The knotting method or one half knot, followed by twisting, will double the fixation strength.

Experimental femoral fracture immobilized by rigid and flexible rods (a rabbit model).

Experimental fractures in rabbits demonstrated that flexible intramedullary rod fixation of the midshaft long bone fracture enhances the fracture healing and may promote early mobility. When compared to rigid fixation, both excess flexibility and excess rigidity inhibited optimal fracture healing. The occurrence of angulation deformities with plastic rods also demonstrate the disadvantage of a very flexible rod.

Early ischial weight-bearing cast brace for femoral fractures.

Three patients with middle or distal femoral fracture were treated with modified ischial weight-bearing cast incorporating only the thigh. The treatment provided adequate stabilization, allowed early ambulation, and promoted fracture healing.

The operative treatment of Achilles tendon injuries.

Twenty cases of Achilles tendon injury treated surgically at the University of Virginia Medical Center from 1970 to 1979 were reviewed and reevaluated with up to 9 years of follow-up. Three treatment groups were identified: Group I--primary repair of a lacerated Achilles tendon; Group II--primary repair of an acutely ruptured Achilles tendon; and Group III--subacute repair of Achilles tendon rupture (performed more than 72 hours after injury). Acute repairs were performed by end-to-end suture.

Acromio-clavicular separation masked by muscle spasm.

Weight-bearing views in suspected acromio-clavicular separation may be misleading if there is extensive spasm of the deltoid and trapezius muscles. The effect of this spasm may be lessened by strapping the weights to the wrist rather than having them hand-held. However, if there is strong clinical suspicion of an acromio-clavicular separation and the stress films, however taken, fail to reveal an upward displacement of the clavicle or widening of the joint space, the study should be repeated after infiltration of the acromio-clavicular joint with local anesthetic.

Spinal evoked potentials from the cervical spine.

Spinal cord evoked potentials were recorded from spinous processes of the lumbar, thoracic, and cervical levels of the spinal column of normal cats in response to direct stimulation of the sciatic nerve and subcutaneous stimulation of the posterior tibial nerve. The typical primary response was altered by changes in location, magnitude, and frequency of the stimulation. Further changes in the primary response could be associated with spinal level of observation.

The treatment of fracture dislocations of the thoracolumbar spine with halofemoral traction and Harrington rod instrumentation.

Although function does not return after complete spinal cord injuries, partial recovery is possible after incomplete lesions Halofemoral traction may produce early decompression of injured neural elements in the spinal canal by anatomic realignment of the spinal column. It also acts to stabilize the very unstable thoracolumbar fracture dislocation and prevent displacement as well as further neurologic trauma. The body jacket is easy to make and apply.