Prediction of wound tensile strength: an experimental study.

Wound cell specimens were obtained using a Cellstic device after 24, 48 and 72 h healing time in guinea-pig skin wounds. Cell counts from these were compared with the tensile strength values of the same wounds 7, 14 or 21 days after operation. No single cell type was predictive of wound tensile strength, although absolute numbers of different cells and selected ratios of cell types on the second or third day after operation were more predictive. Absolute and proportional changes from day 1 to day 2 had the greatest predictive power with a mean error of 9.46 per cent (F = 13.6, P less than 0.0001). The same regression model was predictive in animals with lower wound tensile strengths given perioperative hydrocortisone (3 mg/100 g).

Operative fixation of fractures of the thoracic and lumbar vertebrae by Williams plates with reference to late kyphosis.

Thirty patients with fractures of the thoracic and lumbar spine, treated by the Williams plating technique (with or without fusion) between 1966 and 1978, were reviewed and followed up for an average of 6.5 years (range 2-14 years). The average degree of primary traumatic kyphosis was 11.4 degrees (range 0-33 degrees), and the average degree of late deformation kyphosis during follow-up was 17.4 degrees (range 0-30 degrees). The average loss of operative correction during follow-up was 9.8 degrees. Technical late complications, such as loosening of screws, occurred in half of the patients, but they did not affect the degree of spinal deformation. The corrective result, with reference to late deformity (kyphosis), largely correlated with the degree of primary traumatic kyphotic deformation and the severity of the neurologic lesion. The best late correction result was achieved with moderate primary kyphosis in patients with bursting fractures. Spinal fusion tended to give better results, especially in anterior wedge fractures, in maintenance of the correction of kyphosis, while laminectomy tended to give poorer results. None of the 15 patients with primary complete paraplegia showed improvement, while 80 per cent of patients with incomplete paraplegia made a moderate recovery.