Aims: Pharmocological modulation of skeletal muscle reperfusion injury after an ischaemic insult may improve limb salvage rates and prevent the associated systemic sequelae. Activated Protein c (APC) is an endogenous anti-coagulant with anti-inflammatory properties. The purpose of our study was to evaluate the effects of APC on skeletal muscle ischaemia reperfusion injury and to examine the direct effects of APC on neutrophil activation.

Methods: Adult male Sprague Dawley rats (n=30) were randomised into three groups: control group, I/R group treated with normal saline and I/R treated with APC. Bilateral hind-limb ischaemia was induced by rubber ban application proximal to the level of the greater trochanters for two hours. Treatment groups received either normal saline or APC prior to tourniquet release. Following twelve hours reperfusion, the tibialis anterior was dissected and muscle function assessed electrophysiologically by electrical field stimulation. The animals were then sacrificed and skeletal muscle harvested for evaluation. Skeletal muscle injury was assessed based on myeloperoxidase content, wet-to-dry ratio and histological analysis. The effect of APC on TNF-α stimulated human peripheral blood neutrophils was also examined by measuring CD 18 expression and reactive oxygen species (ROS) generation.

Results: APC significantly attenuated skeletal muscle reperfusion injury as shown by reduced myeloperoxidase content, wet-to-dry ratio and electrical properties of skeletal muscle. These findings were supported by our histological findings. Our in-vitro work demonstrated a reduction in CD 18 expression and ROS generation.

Conclusion: Activated Protein C may have a protective role in the setting of skeletal muscle ischaemia reperfusion injury and this is in part mediated by a direct inhibitory effect on neutrophil activation.

High complication rates and technical difficulties of intramedullary fixation in children with osteogenesis imperfecta has prompted the modification of existing rod systems. The Sheffield telescoping intramedullary road has T-piece which is permanently fixed and is expanded to reduce metaphyseal migration. This study analyses the outcome of this rod system over an 11 year period in two tertiary referral hospitals.

60 rods were inserted in the lower limbs of 19 children with osteogenesis imperfecta. All children had multiple fractures of the bones before rod insertion. 39 rods were inserted into femur, of which 3 were exchange and 4 revision procedures. 21 rods were inserted into tibia. Eight children had intramedullary rodding of both femur and tibia bilaterally. The outcome was measured in terms of incidence of refractures, mobility status, functional improvement and rod related complications.

Our series demonstrates that there is significant reduction in refractures and improvement in the functional status of children with osteogenesis imperfecta following intramedullary fixation. The frequent complication of T-piece separation and the need for re-operation has been overcome with Sheffield modification of rod design. But the incidence of the rod, particularly at the proximal end of femur remains high and further improvement in the design is desirable.