For femoral shaft fracture, damage control orthopaedics entails primary external fixation and subsequent conversion to an intramedullary device (IMN). Sub-clinical contamination of external fixator pin sites is common and it is argued that such an approach risks subsequent local infective complications. We aimed to determine the rate of wound infection following DCO procedures and primary IMN for femoral fracture stabilisation.

Retrospective analysis of a prospectively assembled adult patient database was carried out. Inclusion criteria were femoral #, New Injury Severity Score (NISS) above 20 and survival more than 2 weeks. Two groups, damage control (DCO) and early total care (ETC) (Primary Nail), were formed. Contamination was positive culture from the wound or fixator pin-sites without clinical infection. Superficial infection was a combination of positive bacterial swabs and local or systemic signs of infection. Deep infection was any case requiring surgical intervention with a sub-group requiring removal of femoral metal work (ROMW) also defined.

173 patients met the criteria for inclusion, with 192 fractures (19 bilateral). The mean follow up was 19 months. Patients in the damage control group were more severely injured than those undergoing primary intramedullary nailing (NISS 36 vs 25, p 0.001). There were also more severe (Grade 3 A,B or C) local soft tissue injuries in this group (p 0.05). 98 of the 111 DCO patients underwent subsequent IMN. Others either died without conversion being appropriate, or it was elected to complete treatment with external fixation. The mean time of exchange an ex/fix to a nail was 14.1 days.

Though contamination rates were higher in the DCO group (12.6% vs 3.7%, p 0.05), there was no excess of infective complications (11.1% vs 10.8%). Contamination increased significantly in patients who underwent conversion to IMN after 14 days. Grade 3 open injury was significantly associated with infection irrespective of treatment.

This study demonstrates that infection rates following DCO for femoral fractures are not significantly different to those observed following primary intramedullary nailing. Whilst the overall risk of deep infection in the DCO group did not show any correlation with the timing of converting the external fixator to a nail, the risk of contamination was higher in patients where the exchange nailing was performed after a period of 2 weeks.

Background /Methods: Abbreviated Injury Scale based systems; the ISS, NISS, and AISmax, are used to assess trauma patients. The merits of each in predicting outcome are controversial. A large prospective database was used to assess their predictive capacity using receiver operator characteristic curves.

Results: 13,301 adult patients met the inclusion criteria. All systems were significant outcome predictors for sepsis, multiple organ failure (MOF), length of hospital stay, length of ICU admission and mortality (p 0.0001). NISS was a significantly better predictor than the ISS for mortality (p 0.0001). NISS was equivalent to the AISmax for mortality prediction and superior in patients with orthopaedic injuries. NISS was significantly better for sepsis, MOF, ICU stay and total hospital stay (p 0.0001). Analysis of the ROC curves revealed that the traditional ISS cut-offs for severity of 16, 25 and 50 should be increased to 20, 30 and 55 to provide patients with equivalent outcome.

Conclusions: NISS is superior or equivalent to the ISS and AISmax for prediction of all investigated outcomes in a population of blunt trauma patients. As NISS is easier to calculate, its use is recommended to stratify patients for clinical and research purposes.

Introduction Correct postoperative leg alignment and stability of total knee prothesis over the full range of movement is one critical factor for successful TKA. This can only be achieved by correct implantation of prothesis and soft tissue handling. Still arthrotomy, surgical approach and handling of patella are discussed controversially.

Materials and Methods In a cadaver specimen study we evaluated the influence of everted or subluxated patella on limb axis during balancing of the knee in three different standard surgical approaches. For each approach we operated five knees. Leg alignment was visualised by Ci CT-free DePuy/BrainLAB navigation system. First, physiological leg alignment was measured. Then the different approaches were performed and a.p. leg axis was first measured and compared as well with everted as with subluxed patella in extension and second in 90 degrees flexion.

Results Eversion of patella leads to an alteration in leg axis compared to subluxed patella of 0.58 degrees (SD: 0.03, range: 0.54–0.6) limb axis in valgus direction in full extension. In 90 degrees flexion we found a mean deviation of leg axis of 0.48 degrees (SD: 0.11, range: 0.38–0.6) with everted patella compared to subluxed patella.

Discussion The surgeon has to be aware of this falsifying influence of everted patella to the a.p. limb axis.

Purpose: Intravasation of intramedullary contents and immune activation under the stimulus of cytokines and other inflammatory mediators released during canal preparation are presumed to be significant factors in the evolution of acute lung injury following stabilization of femoral shaft fractures with intramedullary nailing.

We aimed to quantify the development of acute endo-thelial permeability changes (within 4hours from canal instrumentation) with the reamed (RFN) and unreamed (UFN) nailing technique and assess the effect of coexisting lung contusion.

Materials and methods: A standardized sheep model (n=8 animals/group) was used. In the control groups, a thoracotomy without lung injury was performed prior to canal instrumentation. In the study groups a lung contusion of the right middle and lower lobe was induced. Osteosynthesis of the femur was carried out by the reamed (group RFN; standard Synthes reamer, old version) and unreamed technique (group UFN). Bronchoalveolar lavage was performed in order to assess the extent of lung parenchymal damage (permeability). The amount of protein leakage (determination of protein (Lowry assay) and urea (biochemical test) in BALF and serum) at different time points was analysed. Polymorphonuclear leukocyte activation was quantified by chemi-luminescence. IL-8 and coagulatory disturbances (Protein C) were also measured. All animals were sacrificed four hours following canal instrumentation and histological analysis was performed.

Results: In the control groups both the reamed and the unreamed nailing techniques were associated with a significant increase in pulmonary permeability compared to baseline values, p< 0.05. The experimental lung contusion induced prior to canal instrumentation caused also a significant increase in pulmonary permeability compared to baseline values. However, the subsequent canal instrumentation amplified further, significantly so, the degree of pulmonary permeability only in the reamed group (RFN).Both the activation of leukocytes and IL-8 release were also significantly raised following lung contusion and reamed femoral nailing compared to the UFN group with lung contusion (data not shown). Histological analysis illustrated the presence of fat globules in the pulmonary vasculature.

Conclusion: In a standardised sheep model without chest injury, instrumentation of the femoral canal with the reamed and the unreamed nailing techniques induced a rise in pulmonary permeability changes. In the presence of lung contusion, reamed intramedullary femoral nailing provoked a further increase in pulmonary permeability damage, IL-8 release and leukocyte activation. The findings of this study support the view that reaming of the femoral canal can act as an additional stimulus for adverse outcome in the presence of co-existing chest trauma.