Bruce Cruickshank

Upward subluxation of the axis in ankylosing spondylitis: A clinical pathologic report

Upward subluxation of the axis associated with cord compression and death was noted in a patient with a long history of idiopathic ankylosing spondylitis. Upward subluxation of the axis has been recognized in up to 8 per cent of patients with rheumatoid arthritis but it is an exceedingly rare complication of ankylosing spondylitis. In this patient psoriasis and then psoriatic dactylitis developed 26 years after the onset of his ankylosing spondylitis. It is tempting to speculate that the unusual destruction of the joints around the atlas might be due to an added effect of psoriasis on idiopathic ankylosing spondylitis.

Bone apposition rate as an index of bone metabolism.

The rate of bone apposition was studied by labeling bone with four or five sequential doses of oxytetracycline given at equal intervals of 2 or 4 days in rats and rabbits. The rate was estimated in bone formation sites bearing all the doses. This method has the advantage of assessing the rate of new bone mineralization during the active bone-forming phase only. This index of bone formation was found to be independent of the location of bone samples in the skeleton, and therefore might be under the influence of general body mechanisms only. Preliminary study in the rats indeed yielded results indicating that this bone apposition rate is accelerated by dietary deficiency in calcium.

Regeneration of vas deferens after vasectomy

A total of 338 specimens obtained from 182 patients undergoing reversal of previous vasectomies have been studied. The major histologic features are sprouting of tubules and extravasation of sperm. Neo-tubules grow only from the proximal end of the divided vas and were seen in 136 specimens. Sperm were present in the neo-tubules in 61 specimens, but in the lumen of the proximal vas in 88 per cent of all patients. Extravasation of sperm had occurred from the neo-tubules in 64 specimens. In 57/154 patients operated on bilaterally at the same time, regeneration was unilateral. The conclusion from the analysis of factors responsible for this selectively proximal process is that sperm secretion was probably a major factor but was certainly not the only factor responsible.

The response of bone apposition rate to some nonphysiologic conditions

The response of bone apposition to some nonphysiologic conditions was investigated. In rabbits, the normal osteogenic rhythm was totally abolished shortly following treatment of hydrocortisone at a dose of 2 mg/kg body weight daily. A new rhythm developed after the treatment was continued for 20 1/2--34 days. The rate of bone apposition was significantly depressed compared to normal data reported previously. In rats receiving one U.S.P. unit of parathyroid extract daily for 14 days, the rate of bone apposition was significantly higher than that in control rats. In both sepcies, the response to an exogenous hormone was identified for all skeletal locations. It was concluded that new bone apposition was a function of activated osteoblasts, and that this function responded only to general body control mechanisms.

Starch granulomas after transurethral resection of bladder tumors

Starch granulomas have been observed in 3 patients in a series of 140 under treatment for bladder cancer during the period 1949 to 1969 in one hospital. The lesions were observed at the fourth or subsequent transurethral procedure, suggesting strongly that the starch had been introduced at a previous transurethral procedure. The granulomatous reaction may simulate a recurrence of the initial bladder tumor.