The systemic arterial pressure has been used as a guide for determining the susceptibility to surgical bleeding during controlled hypotensive anaesthesia. Arterial hypotension is not, however, necessarily accompanied by venous or intraosseous hypotension. The main source of bleeding during posterior spinal surgery is the bone and is venous rather than arterial.

The intraoperative blood loss, the intraosseous pressure (IOP) within the first thoracic vertebral body, and the systemic arterial pressure were measured in 27 patients during cervical laminoplasty for spondylotic myelopathy. The intraoperative blood loss correlated significantly with the vertebral IOP (p = 0.0073, r = 0.499), but not with systemic arterial pressure, age, or body-weight. The systemic arterial pressure did not correlate with the vertebral IOP. The mean value of the mean arterial pressure throughout the operation varied between 74 and 110 mmHg.

The findings suggest that the vertebral IOP parallels surgical bleeding during posterior spinal surgery under normotensive anaesthesia and that patients with a low arterial pressure do not necessarily have a low IOP.

A combined open and percutaneous operative technique has been devised for repair of tendo Achillis. This minimises postoperative scarring. We compared the long-term results of 12 patients treated by this method with the results of 10 who had undergone an open repair. The combined open and percutaneous repair gave significantly better relief of symptoms during everyday activities (p < 0.05), better single-limb hopping (p < 0.02) and a greater chance of returning to sport (p < 0.01). There were no significant differences between the two treatments as regards to active range of ankle motion, calf circumference or the ability to stand on tiptoe. The new technique gave better cosmetic results.