Failure of surgery for scaphoid non-union is associated with smoking.

Scaphoid fractures predominantly affect young men, in whom the UK smoking prevalence approaches 40%. We examined the association between smoking and failure of non-vascularized bone grafting and screw fixation for scaphoid non-union and delayed union in a retrospective cohort study. Adequate follow-up was obtained in 64 of 87 patients treated (74%). Union was defined as the presence of trabecular continuity on at least two films from a four-view radiographic series. Union was achieved in 47 of 64 cases. Seventeen were smokers. Thirteen of the 17 patients with non-union were smokers (relative risk 3.7; 95% CI: 1.3-10.1, p=0.005). Proximal pole fractures, long injury-grafting interval and non-compliance were not more frequent in smokers than non-smokers. Smoking is strongly associated with failure of union after screw fixation and non-vascularized bone grafting of the scaphoid. Smokers should be advised to avoid smoking pre-operatively and during the healing period.

Osteonecrosis in retrieved femoral heads after failed resurfacing arthroplasty of the hip.

We present the histological findings of bone retrieved from beneath the femoral components of failed metal-on-metal hip resurfacing arthroplasties. Of a total of 377 patients who underwent resurfacing arthroplasty, 13 required revision; for fracture of the femoral neck in eight, loosening of a component in three and for other reasons in two. None of these cases had shown histological evidence of osteonecrosis in the femoral bone at the time of the initial implantation. Bone from the remnant of the femoral head showed changes of osteonecrosis in all but one case at revision. In two cases of fracture which occurred within a week of implantation, the changes were compatible with early necrosis of the edge of the fracture. In the remaining six fractures, there were changes of established osteonecrosis. In all but one of the non-fracture cases, patchy osteonecrosis was seen. We conclude that histological evidence of osteonecrosis is a common finding in failed resurfaced hips. Given that osteonecrosis is extensive in resurfaced femoral heads which fail by fracture, it is likely to play a role in the causation of these fractures.

Abnormal ulnar nerve anatomy in the distal forearm pre-disposes to post-traumatic ulnar neuritis at the wrist.

Anatomical variations of the ulnar nerve have been described at the level of the elbow and in Guyon's canal, while the path in the forearm has always been assumed to be constant. We present a case of compressive ulnar neuropathy at the wrist pre-disposed by a presumed congenital variation of the path of the ulnar nerve at the level of the wrist which improved following surgical release of the constriction caused as a result of it.

Use of topically applied rt-PA in the evacuation of extensive acute spinal subdural haematoma.

Spontaneous spinal subdural haematoma is a rare cause of spinal cord compression, usually confined to a few vertebral levels. When the haematoma extends over several spinal segments, surgical decompression is a major undertaking. Recombinant tissue plasminogen activator (rt-PA) has previously been used in a number of surgical procedures, but not in the setting of acute spinal subdural haematoma. A minimally invasive technique of decompression, using topical rt-PA, is presented in two patients with extensive spinal intradural haematoma. Two patients receiving long-term anticoagulation therapy presented with acute-onset back pain progressing to paraparesis. Magnetic resonance imaging of the spine demonstrated spinal subdural haematomas extending over 15 vertebral levels in one patient and 12 in the other. An angiography catheter was introduced into the subdural space through a limited laminectomy. Thrombolysis and evacuation of haematoma was then achieved by intermittent irrigation of the subdural space with rt-PA, followed by saline lavage. Postoperative imaging demonstrated satisfactory decompression in both patients. There was significant improvement of neurological function in one patient. Topical application of rt-PA for spinal subdural haematoma allows evacuation of the haematoma through a limited surgical exposure. Decompression of the subdural space by this minimally invasive technique may be advantageous over extensive surgery by minimising surgical exposure, reducing postoperative pain and risk of neuronal injury. This technique may be useful in patients presenting with compression extending over several vertebral levels or poor surgical candidates.