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.

Assessment of the AO classification of intracapsular fractures of the proximal femur.

There are a number of classification systems for intracapsular fractures of the proximal femur, but none has been shown to be practical with satisfactory reproducibility and accurate predictive value. We have investigated the AO classification and evaluated intra- and interobserver accuracy and its value in predicting treatment and outcome. We found it to have very poor intra- and interobserver reliability and to be of limited predictive use for the outcome of treatment. A simplified system in which the subdivisions were allocated to one of three groups of undisplaced, displaced and basal fractures was found to be of value. We conclude that this is the only division which is appropriate for these fractures and that the AO system for intracapsular fractures is too complicated and should not be used.

Fractures of the hip: does the type of fall really affect the site of fracture?

The purpose of this study was to test accepted theories relating the characteristics of a fall to the anatomical site of hip fracture in the elderly. Twisting injuries are said to result in intracapsular fractures and falls directly onto the side are said to result in extracapsular fractures. 618 consecutive patients with a hip fracture were studied prospectively by being questioned with regard to the nature of their fall. After exclusions, 552 patients were left in the study. Of these, 324 patients sustained intracapsular fractures and 228 extracapsular fractures. More intracapsular fractures were associated with a fall onto the affected side than extracapsular fractures and rotation at the hip during the fall had a significant association with extracapsular fractures. In this study 84 per cent of all fractures occurred by falling directly onto the affected side. The clinical significance of this finding is that protective padding on the hip might be beneficial.

Macrophage recruitment during limb development and wound healing in the embryonic and foetal mouse.

Macrophages play a pivotal role in the adult inflammatory response to wounding. They are directly responsible for cellular debridement and, by providing a source of growth factors and cytokines, they recruit other inflammatory and fibroblastic cells and influence cell proliferation and tissue remodelling. In this paper we investigate the role of macrophages in clearing areas of programmed cell death in the developing embryo and also their role in embryonic and foetal wound healing. Immunocytochemistry using the monocyte/macrophage-specific monoclonal antibody, F4/80, reveals a close association between areas of programmed cell death in the remodelling interdigital regions of the mouse footplate and of F4/80-positive cells, suggesting that monocyte-derived macrophages, and not locally recruited fibroblastic cells, as previously believed, are responsible for phagocytosing and clearing areas of interdigital apoptosis. Our studies of wound healing reveal that macrophages are not recruited to, and therefore cannot be playing an active role in the healing of, excisional wounds made in the mouse embryo at any stage up until E14.5. Beyond this transition stage we see a significant recruitment of macrophages within 12 hours of wounding. We find that macrophages can be attracted to wounds in earlier embryos if the wound results in significant cell death such as after burning.

A study of wound healing in the E11.5 mouse embryo by light and electron microscopy.

In this paper we report our light and electron microscopic studies of the healing of a simple excisional lesion to the E11.5 mouse embryo hindlimb. The wounded living embryo is cultured in a roller bottle and under such conditions the lesion is completely re-covered with epithelium by 24 hr. We discuss how our studies of such a simple wound healing model may offer insight into the mechanisms of tissue repair generally.

Clinical implications of embryonic wound healing.

An examination of research on the healing abilities of animal embryos and a consideration of its implications for human adult wound healing.

Growth factors and cutaneous wound repair.

The healing of an adult skin lesion is a well studied but complex affair of some considerable clinical interest. Endogenous growth factors, including the EGF, FGF, PDGF and TGF beta families, are released at the wound site and presumed to be a necessary part of the natural wound healing machinery. Moreover, members of each of these families have been shown to enhance healing if added exogenously to a wound site. In this review we shall briefly discuss what is known about the mechanics and cell biology of adult wound healing, describe the normal cellular source of growth factors during the healing process and, with reference to their known capacities in tissue culture, speculate as to how particular growth factors might be able to enhance healing.