Background. We switched our antibiotic prophylaxis for elective hip and knee surgery from cefuroxime to flucloxacillin with single dose gentamicin in order to reduce the incidence of C. Diff diarrhoea. More patients subsequently appeared to develop acute kidney injury (AKI). Methods. During a twelve month period we examined the incidence of AKI sequentially in 198 patients undergoing elective hip or knee surgery: cefuroxime (n = 48); high dose flucloxacillin (median 8g) (n = 52); low dose flucloxacillin (median 4g) (n = 46); and cefuroxime again (n = 52). Results. There were no statistically significant differences between the four groups by chi-square tests for age, gender, nature of operation (hip or knee surgery), American Society of Anaesthesia (ASA) grade, mode of anaesthesia (spinal ± general anaesthetic v GA), baseline serum creatinine, pre-operative co-morbidity (hypertension, diabetes), pre-operative medication (NSAIDs, ACEI/ARBs or betablockers) and post-operative hypotension. Patients receiving high dose flucloxacillin required more vasopressors during surgery (p = 0.02 by Kruskal-Wallis test). The proportion of patients in each antibiotic group with any form of AKI by RIFLE criteria was: first cefuroxime group (8%), high dose flucloxacillin (52%), low dose flucloxacillin (22%), second cefuroxime (14%) (p < 0.0001). Odds ratios (OR) for AKI derived from a multivariate logistic regression model and arbitrarily assigning an OR of 1 to first cefuroxime group, were: high dose flucloxacillin 14.5 (95% CI, 4.2–49.7); low dose flucloxacillin 3.0(0.8–10.8); cefuroxime again 2.0(0.5–7.7). Three patients required temporary haemodialysis. Biopsies in two of these showed acute tubulo-interstitial nephritis. All three patients belonged to the high dose flucloxacillin group. None of the patients developed C Diff diarrhoea. Summary. We have shown a strong association between high dose flucloxacillin with single dose gentamicin prophylaxis and subsequent development of AKI which was not confounded by any of the co-variates we measured

Patients with pelvic and acetabular fractures have a high risk of developing thromboembolic complications. Despite routine screening, the risk of PE remains high and may develop in patients with negative DVT screening. The search for a means to identify the patient ‘at risk’ has been elusive. 537 consecutive patients, referred to Royal Adelaide Hospital over a 20 year period for treatment of pelvic and acetabular fractures, were evaluated prospectively for pulmonary embolus (PE). 352 patients referred directly to the author were treated with variable dose heparin as prophylaxis to venous thromboembolic (VTE) disease. 184 patients primarily admitted under the general surgeons or to ITU, prior to referral to the author, were treated with fixed dose heparin or Enoxaparin. All patients were followed prospectively to determine the rate of pulmonary embolus. The heparin dosage requirements of those who developed pulmonary emboli were compared to those who did not. Patients were also identified for whom a clinical diagnosis of deep venous thrombosis (DVT) was made during the study and their heparin dosage requirements were determined. 7 of 352 patients treated with variable dose heparin developed PE (1.98%). 13 of 184 patients treated with fixed dose heparin, Enoxaparin, or combinations, developed PE (7.06%). An incidental finding of DVT was made in 36 patients. Of these, 10 patients (2.8%) were treated with variable dose heparin and 26 patients (14.1%) with fixed dose heparin or Enoxaparin. The average Injury Severity Score was higher in patients treated with variable dose heparin than those treated with fixed dose regimes. Patients treated with variable dose heparin who developed PE showed a progressively increasing heparin requirement. The majority of patients who did not develop PE (72%) showed a progressively decreasing heparin requirement (suggesting reversal of a prothrombotic state). 21% showed an initial increasing heparin requirement followed by a decreasing requirement (suggesting a prothrombotic state that was reversed, e.g. a DVT successfully treated by the increasing heparin dose provided by a variable dose regime). 4% manifested a static heparin requirement (suggesting maintenance of a prothrombotic state). 8 patients treated with variable dose heparin developed DVT. 6/8 patients manifested a phase of progressively increasing heparin requirement, followed by a decreased requirement, and 2/8 patients manifested a sustained level of heparin requirement. Patients with pelvic and acetabular fractures treated with variable dose heparin showed a rate of PE (1.98%). This is remarkably low compared with published rates of PE in such patients, and particularly compared with those patients treated only with chemoprophylaxis. The rate of PE was 3.5x higher and the rate of DVT was 5x higher in patients treated with fixed dose heparin or Enoxaparin. Patients who developed PE or DVT manifested an increasing heparin requirement. An increasing dosage of heparin may protect the ‘at risk’ patient from venous thromboembolism. Fixed dose unfractionated heparin/LMWH may be insufficient to treat the ‘at risk’ patient. An increasing heparin requirement may identify the patient ‘at risk’

Introduction. The vast majority of orthopaedic surgeons use C-arm fluoroscopy in the operating theatre when building a circular external fixator. In the absence of previous research in this area, we hypothesised that the surgeon who builds a circular external fixator is exposed to a greater amount of radiation purely as a result of the presence of the metallic fixator in the x-ray beam. The aim of our study therefore was to investigate how the presence of a circular external fixator affects the radiation dose to the surgeon and the surgical assistant. Materials & Methods. A simulated environment was created using a radiolucent operating table, an acrylic lower limb phantom (below knee segment), various configurations of metalic circular external fixation, and a standard size C-arm image intensifier. The variables investigated were 1. the amount of metal in the beam 2. the orientation of the beam (PA vertical vs lateral) 3. the horizonal distance of the person from the beam (surgeon vs assistant) and 4. the vertical distance of the various body parts from the beam (e.g. thyroid, groin). In terms of radiation dose, we recorded two things : 1. the dose produced by the image intensifier 2. the dose rate at standardised positions in the operating theatre. The latter was done using a solid-state survey sensor. These positions represented both where the surgeon and surgical assistant typically stand plus the heights of their various body regions relative to the operating table. Results. The effect of the presence of the circular external fixator : all frame constructs tested resulted in a statistically significant greater radiation dose both produced by the image intensifier and received by the surgical team. The effect of the beam orientation : the PA (vertical) orientation resulted in a statistically significant greater radiation dose for the surgeon than did the lateral orientation, but made no difference for the assistant. The effect of horizontal distance from the beam : unsurprisingly, the surgeon (who was closer to the beam) received a statistically significant greater radiation dose than the assistant. The effect of vertical distance from the beam : for the surgeon, the dose received was highest at the level of the phantom leg / frame, whilst for the assistant there was no statistically significant difference for any level. Conclusions. To our knowledge, this is the first study investigating the radiation dose rate to the orthopaedic surgeon when building a circular external fixator. We found that the surgeon does indeed receive a ‘double whammy’ because the image intensifier puts out a greater amount of radiation plus the metalic frame scatters more of the x-ray beam. Whilst the amounts are relatively small, we think that it's important to quantify doses that orthopaedic surgeons receive to ensure optimal radiation practices

Background. Recent literature points out the potential interest of standing and sitting X-rays for the evaluation of THA patients. The accuracy of the anterior pelvic plane measures is questionable due to the variations in the quality of lateral standing and sitting X-rays. The EOS® (EOS imaging, Paris, France) is an innovative slot-scanning radiograph system allowing the acquisition of radiograph images while the patient is in weightbearing position with less irradiation than standard imagers. This study reports the “functionnal” positions of a 150 THA cohort, including the lateral orientation of the cups. Methods. The following parameters were measured: sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI) and anterior pelvic plane (APP) sagittal inclination (ASI), frontal inclination (AFI) and planar anteversion (ANT). Irradiation doses were calculated in standing and sitting acquisitions. Variations of sagittal orientation of the cup were measured on lateral standing and sitting images. Descriptive and multivariate analysis were performed for the different parameters studied. Results. The mean doses for full body were 0,80 mGy ± 0,13 for standing position and 0,94 mGy ± 0,25 for sitting position. The mean value for PI was 55,8° ± 11,4. The mean values standing position were 39,01° ± 9,9 for SS, 17,23° ± 10,2 for PT, and 0,74° ± 8,4 for APP. The mean values were 46,36° ± 9,8 for AFI, 39,49° ± 15,1 for ASI and 22,09° ± 11,1 for ANT. In sitting position, the mean values were 20,87° ± 10,2 for SS, 35,37° ± 13,1 for PT and 21,13° ± 11,2 for APP. The mean values were 56,41° ± 12,3 for AFI, 51,71° ± 14,7 for ASI and 33,45° ± 12,9 for ANT. Conclusions and Clinical Relevance. Unexpected variations of the anterior pelvic plane can be observed as well as the influence of pelvic incidence on pelvic orientation. The EOS® imaging system provides new informations regarding the pelvis functionnal anatomy in THA patients with potential applications for the study of unstable cases and wear phenomenons

Purpose. Developmental exposure to estrogens has been shown to affect a number of organ systems, including long and short bones. Epigenetic effects of DES exposure have been shown to affect the third generation of progeny. Furthermore, recent studies have shown that environmental exposure to estrogen-like compounds is much higher than originally anticipated. This study aims to discover the effect of in utero exposure to a well-known estrogen agonist, diethylstilbestrol (DES), on lumbar bone, intervertebral disc (IVD), and articular cartilage. Femoral bone was studied to determine the specificity of the effect. Method. C57bl/6n pregnant mice were dosed orally with vehicle (peanut oil) or 0.1, 1.0 and 10 g/kg/day of DES on gestational days 11–14. Male and female pups were allowed to mature without further treatment until 3 months of age, at which point they were divided into swim and sedentary groups. After sacrifice, bone mineral density (BMD), bone mineral content (BMC), bone area (BA), and trabecular bone area (TBA) of the lumbar vertebrae and femur were measured using a PIXImus Bone Densitometer System (GE Medical Systems). Glycosaminoglycan (GAG) content (proteoglycan) was measured by the DMMB assay. Histological analysis of proteoglycan was performed with Safranin O staining. Intervertebral disc height was measured using NDP software (Leeds, UK). Statistical analysis was performed using analysis of variance (ANOVA) followed by Fisher's Protected Least Significant Difference (PLSD). A p-value of < 0.05 was considered statistically significant. Results. At all the doses studied, DES had no significant effect on lumbar and femoral BMD in both males and females. The lumbar BMC, however, was significantly increased in female swims at both the highest and lowest dose of DES, while the femoral BMC was only increased at the highest. The males, on the other hand, showed a decreased BMC at the highest dose of DES for both lumbar and femoral bone. Female swim group had an increased BA at the highest dose of DES while the male swims showed a decreased BA for femoral bone. The TBA showed a similar pattern. GAG analysis of lumbar IVDs showed a decrease at the lowest doses but a significant increase at the highest doses for both swim and sedentary groups. Histology showed morphological changes of the IVD and articular cartilage for all doses of DES. Conclusion. The effect of in utero DES exposure is more important on lumbar than on femoral bone. The effect was mainly observed at high dose of DES, except for BA that is also affected by low dose DES in lumbar bones. Results suggest that environmental estrogen contaminants might impact developmental lumbar bone growth and mineralization in mice. Further studies measuring the impact of environmental estrogen mimics, such as bisphenol A, are then warranted

Introduction. Rivaroxaban, an oral factor Xa inhibitor, has been approved by USFDA for prophylaxis of deep vein thrombosis (DVT) and pulmonary embolism (PE) in hip and knee arthroplasties. Its indication in hip fracture surgery has been recently recommended in Asian venous thromboembolism (VTE) guidelines. Phase II dose-ranging study demonstrated that 5 mg rivaroxaban is as effective as enoxaparin for VTE prophylaxis with lower incidence of bleeding complication than the recommended 10 mg dose. Rivaroxaban is recommended to be given 6–8 hours after operation. However, many surgeons are hesitated to follow this guideline since it might increase post-operative blood loss and wound complication. Elderly patients, such as hip fracture patients, are generally at more risk of bleeding and wound complications. These patients may benefit from using the delayed and reduced-dose regimen. Methods. Since July 2011, all eligible hip fracture patients treated by single group of surgeons were given 5mg daily dose of rivaroxaban for VTE prophylaxis. Initial dose of rivaroxaban was given after drain had been removed (24–36 hours post-operatively) and continued for 14 days. Inclusion criteria are femoral neck fracture or intertrochanteric fracture in patients age 60 and over. Exclusion criteria are pathologic fracture, reoperation for failed fixation, chronic anticoagulant therapy, and allergy to rivaroxaban. Criteria by Aniwan and Rojnackarin were used for clinical diagnosis of DVT and PE. Suspected case of DVT and PE were sent for confirmation with Doppler U/S and Pulmonary Artery CT scan, respectively. All bleeding and wound complications were recorded. Numbers of blood transfusion were also recorded. Patients were followed for at least 6 weeks, all complications were recorded. Results. There were 79 hip fracture patients matching our criteria. They were composed of 54 femoral neck fractures and 25 intertrochanteric fractures. Mean age of patients was 76.3 years. All femoral neck fractures were treated with bipolar hemiarthroplasty and intertrochanteric fractures were treated with short cephalomedullary nail. Two patients (2.6%) were compatible with clinical criteria of DVT. However, Doppler ultrasound examinations do not demonstrate thrombus or intraluminal filling defect. There was no suspected case of PE. There was no major hemorrhagic wound complication requiring reoperation. Minor wound complications include 7 (8.9%) cases of prolong serous oozing and 1 (1.3%) superficial wound infection. Extrasurgical site bleeding includes 1 (1.3%) upper GI bleeding and 2 (2.5%) hematuria. None of the patients received more than 2 units of blood transfusion. Discussion and Conclusion. Delayed and reduced-dose regimen of rivaroxaban is effective for VTE prophylaxis in hip fracture patients. There is no major hemorrhagic wound complication. Nonetheless, extrasurgical site bleeding is frequent. Further randomized comparative study with larger number of patients should be performed to demonstrate whether the benefits of the modified regimen existed or not

Fluoroscopic guidance is common in interventional pain procedures. In spine surgery, injections are used for differential diagnosis and determination of indication for surgical treatment as well. Fluoroscopy ensures correct needle placement and accurate delivery of the drug. Also, exact documentation of the intervention performed is possible. However, besides the patient, interventional pain physicians, surgeons and other medical staff are chronically exposed to low dose scatter radiation. The long-term adverse consequences of low dose radiation exposure to the medical staff are still unclear. Especially in university hospital settings, where education of trainees is performed, fluoroscopy time and total radiation exposure are significantly higher than in private practice settings. It remains a challenge for university hospitals to reduce the fluoroscopic time while maintaining the quality of education. Multiple approaches have been made to reduce radiation exposure in fluoroscopy, including the wide spread use of pulsed fluoroscopy, or rarely used techniques like laser guided needle placement systems. The Zero-Dose-C-Arm-Navigation (ZDCAN) allows an optimal positioning of the c-arm without exposure to radiation. For training purposes, relevant anatomical structures can be highlighted for each interventional procedure, so injection needles can be best positioned next to the target area. The Zero-Dose-C-Arm-Navigation (ZDCAN) module was developed to display a radiation free preview of the expected fluoroscopic image of the spine. Using an optical tracking system and a registered 3D-spine model, the expected x-ray image is displayed in real-time as a projection of the model. Additionally, selected anatomical structures including nerve roots, facet joints, vertebral discs and the epidural space, can be displayed. A seamless integration of the ZDCAN in a c-arm system already used in clinical practice for years could be achieved. For easy use, a tool was developed allowing the admission and use of regular single-use syringes and spinal needles. Accordingly, these can be used as pointers in the sterile area, a sterilization of the whole tool after every single injection is not required. We evaluated the efficiency and accuracy of this procedure compared to conventional fluoroscopically guided interventional procedures. In sawbones of the lumbar spine, facet joint injections (N = 50), perineural injections (N = 46) and epidural injections (N = 20) were performed. Highlighting the target area in the radiation free preview model, an optimal positioning of the c-arm could be achieved even by unskilled medical staff. The desired anatomical structures could be identified easily in the x-rays taken, as they were displayed in the 3D model aside. As already seen evaluating a previous version of the ZDCAN module for the lower limb, the total number of x-ray images taken could be reduced significantly. Compared to the conventional group, the number of x-ray images required for facet joint injections could be reduced from 12.5 (±1.1) to 5.7 (±1.1), from 5.4 (±1.8) to 3.8 (±1.3) for perineural injections and from 4.1 (±0.9) to 2.1 (±0.3) for epidural injections. Total radiation time was reduced accordingly. Likewise, the mean time needed for the interventional procedure could be reduced from 168.3 s (±19.1) to 131.4 s (±16.8) for facet joint injections, was unchanged from 97.7 s (±26.0) to 104.7 s (±31.0) for perineural injections and from 60 s (±14.9) to 52 s (±7.1) for epidural injections. The ZDCAN is a powerful tool advancing conventional fluoroscopy to another level. Using the radiation free preview model, the c-arm can easily be positioned to show the desired area. The accentuated display of the target structures in the preview model makes the introduction to fluoroscopy guided interventional procedures easier. This feature might reduce the learning curve to achieve better clinical results with lower radiation dose exposure. Thus, the ZDCAN can be a tool to improve education in university hospital settings for physicians as well as for medical staff while reducing radiation dose exposure in general use

A radiation sterilisation dose (RSD) of 25 kGy is commonly recommended for sterilisation of allograft bone. However, the mechanical and biological performance of allograft bone is gamma dose-dependent. Therefore, this study aimed to apply Method 1 – ISO 11137–2: 2006 to establish a low RSD for frozen bone allografts. Two groups of allograft bones were used: 110 femoral heads (FH) and 130 structural and morselized bones (SMB). The method included the following stages: bioburden determination using 10 FHs and 30 SMBs; verification dose selection using table six in the ISO standard and bioburden; the verification dose was used to irradiate 100 samples from each group; then irradiated bone segments were tested for sterility. The criterion for accepting the RSD as valid is that there must be no more than two non-sterile samples out of 100. The radiation sterilisation dose is then established based on table five, ISO 11137– 2: 2006. The bioburden of both types of frozen allograft was zero. The verification dose chosen was 1.3 kGy. Two hundred bone segments were irradiated at 1.3 kGy. The average delivery gamma dose was 1.23 kGy (with minimum dose of 1.05 kGy maximum dose of 1.41kGy), which is acceptable according to the ISO standard. Sterility tests achieved 100% sterility. Accordingly, 11 kGy was established as a valid RSD for those frozen bone allografts. A reduction in the RSD from 25 kGy to 11 kGy will significantly improve bone allograft mechanical and biological performance because our data show that this dose level improves the mechanical toughness and osteoclast activity of the allograft by more than 10 and 100 percent, respectively, compared with bone allografts irradiated at 25 kGy. A low RSD of 11 kGy was established for allograft bones manufactured at Queensland Bone Bank by applying dose validation method 1 (ISO 11137.2-2006) that is internationally accepted

Introduction. For preoperative planning of Total Hip Arthroplasty (THA) it is paramount to choose the correct implant size to avoid subsidence with too small a component or fracture with too large a component. This planning can be done either in 2D or 3D. 2D templating from X-rays frontal images remains the gold standard technique in THA preoperative planning despite the lower accuracy with uncemented components. 3D planning techniques require a CT-Scan examination overexposing patients to radiation. Biplanar EOS. ®. radiographs are an alternative to obtain bone 3D reconstructions with a very low dose of radiation. The objective of this study was to evaluate the accuracy and reproducibility a novel 3D technique for THA preoperative planning based on biplanar low-dose radiographs. Materials and methods. 31 patients (20 women, 11 men, average age 66.1 y/o) who underwent a primary THA (Hardinge anterolateral approach) were included. Two senior orthopedic surgeons (Op_1 and Op_2) performed the pre-operative planning: (1) In 2D superimposing templates of the cup and the stem on CR radiographs. The CR images had a magnification coefficient of 1.15. (2) In 3D using dedicated hipEOS (EOS Imaging, France) software. 2D planning was performed once by each operator, 3D planning twice. 3D planning with hipEOS [Figure 1] was performed by importing 3D models of the stem and cup and superimposing them on frontal-lateral EOS. ®. radiographs. This software proposes an initial estimate of the components size and position. If necessary, the user can correct the size of the stem and perform translations and rotations of the 3D models in order to correct the position, while clinical parameters such as the cup anteversion and inclination, as well as the femoral offset and leg length are automatically recalculated. To evaluate the accuracy, we have compared the 2D and 3D planning with respect to the actual size implanted during the surgery. To evaluate reproducibility we have calculated the Intra-class Correlation Coefficient (ICC) of both techniques. Results. In 2D, the stem size was planned in 69% of cases within ± 1 size with respect to the actual size, compared to 83% in 3D [Table 1]. The ICC [table 2] for stem planning was 0.91 in 2D, and 0.88 in 3D. In 2D, the cup size was planned in 87% of cases within ± 1 size, compared to 92% in 3D. The ICC for cup planning was 0.71 in 2D, and 0.84 in 3D. Discussion. The 3D planning technique proposed is accurate and reproducible. 3D planning based on biplanar EOS. ®. radiographs can become an alternative to 2D techniques which require calibration devices. The method proposed is a novel concept of 3D THA planning with a very low radiation dose, if compared to CR and CT [Delin, Eur J Radiol 2013; Deschênes, Spine 2010]. Conclusion. The 3D preoperative planning of THA based on EOS. ®. biplanar radiographs proved to be accurate and reproducible if compared to the ‘gold standard’ technique. A prospective study to evaluate clinically relevant parameters of THA surgeries such as the leg length and the femoral offset with hipEOS is in progress

Introduction. Viscosupplementation is used widely to provide symptomatic relief to patients with knee OA. This study aimed to compare the efficacy and safety of the standard (3×2ml) and single (1×6ml) dosing regimens of hylan G-F 20. Methods. Prospective, randomized, blinded (reviewers), comparative independent study. Inclusion criteria was OA knee pain e 60mm on a 100mm VAS; no prior intra articular (IA) injection. Patients were randomised to recieve 1 × 6mL or 3 × 2mL hylan G-F 20. Follow-up at 1, 6, 12, 26 and 52 weeks. Analgesics prohibited for 24 hours prior to follow-up assessments and NSAID's for 26 wks. All adverse events (AE) were recorded. Primary outcome measure: Target knee pain (VAS) at 26 weeks. Secondary outcome measures included WOMAC, Oxford knee score, SF12. Results. 412 patients were randomized (1 × 6mL N=194, 3 × 2 mL N=218). There were no significant differences in age, gender or grade of OA. Injection and/or treatment-related AE (all mild/moderate) were reported in 10.5% (3 × 2 mL) and 9.1% (1 × 6 mL) of patients Significant pain reduction was observed in both groups at 26 weeks (3 × 2 mL: 50% (mean) decrease, 1 × 6mL: 45%). There were no significant differences between groups for any of the primary or secondary outcome measures at 26 weeks. Discussion and Conclusion. Single dose of 6 mL hylan G-F 20 offer comparable safety and efficacy to 3 × 2 mL at 26 weeks. It provides both the patients and physicians a choice with the potential additional benefits of reduced operational costs

Introduction. The gold standard for knee surgery is the restoration of the so-called «neutral mechanical alignment ». Recent literature as pointed out the patients with «constitutional varus »; in these cases, restoring neutral alignment could be abnormal and even undesirable. The same situation can be observed in patients with «constitutional valgus alignment ». To date, these outliers cases have only been explored focusing on the lower limb; the influence of the pelvic morphotype has not been studied. Intuitively, the pelvic width could be a significant factor. The EOS low dose imaging technique provides full body standing X-rays to evaluate the global anatomy of the patient. This work explores the influence of the pelvic parameters on the frontal knee alignment. Material and methods. – We included 170 patients (340 lower extremities). 2 operators performed measurements once per patient on AP X-rays. The classical anatomical parameters were:. –. Femoral mechanical angle (FMA). –. Tibial mechanical angle (TMA). –. Hip knee shaft angle (HKS). –. Hip knee ankle angle (HKA). –. Femoral and tibial lengths. The morphotype was evaluated by:. –. the distances between the center of two femoral heads (FHD), between knees (KD) and between ankles (AD). –. the medial neck-shaft angle (MNSA). –. the femoral offset. The horizontal distance between the limb mechanical axis (line passing from center of the femoral head to the center of the ankle) and the center of the knee was called the intrinsic mechanical axis deviation (IMAD) (fig 1). The horizontal distance between the pelvic mechanical axis (line from the center of the sacral plate to the center of the ankle) and the center of the knee was called the global mechanical axis deviation (GMAD) (fig 2). Inter-Operator Reliability was calculated with Intra-class Correlation Coefficient (ICC) and Inter-Reader Agreement was assessed with Bland-Altman test. A relationship between IMAD and GMAD to the other parameters was assessed using Pearson's correlation coefficient. Results. Inter-Operator Reliability was high for femoral offset, TMA and MSNA (ICC > 0,88) and very high for the other parameters (ICC > 0,93). These values are given in table 1 and all the 2D parameters are given in the table 2. IMAD was significantly correlated with HKA (r = 0,99), FMA (r = −0,58), TMA (r = −0,61) and KD (r = 0,72). GMAD was significantly correlated with HKA (r = 0,94), FMA (r = −0,53), TMA (r = −0,60) and KD (r = 0,67). Two groups were identified according to pelvic width (FHD):. Group 1 (standard patients): Pelvic width < 18 cm (164 lower extremities). Group 2 (wide pelvis): Pelvic width ≥ 18 cm (176 lower extremities). For standard patients the FHD is a significant parameter, whereas the proximal femoral anatomy (offset and MNSA) are more relevant for wide pelvis. Conclusion. Accurate analysis of the morphotype of the lower limbs is essential for planning femoral or tibial osteotomy and knee prostheses. Taking into account pelvic morphotype can provide additional informations for the axes restoration and the detection of outliers patients

Introduction. To evaluate the clinical success and hip pain and function of patients with infected hip replacement treated by two-stage exchange using a temporary implant with high dose vancomycin added to the antibiotic cement at the first stage revision. Method. Thirty-three hips in 32 patients (median 67 yrs) underwent first stage revision using the PROSTALAC™ system (n=27) or a self-made system using an Elite long stem (n=6). Infection was diagnosed after 19 primary, 11 revision and 3 hemiarthroplasty hip replacements. Patients were reviewed regularly clinically and by questionnaire. The median follow-up was 3 years. Results. Five hips (15%) had repeat first stage for persistent infection. Twenty-four hips (73%) progressed to second stage. Five hips (15%) did not progress to second stage. Four hips (12%) underwent excision arthroplasty. There was a further one recurrence of infection (4%) requiring repeat two stage revision at 3 years. Patients reported, on average, minimal to no hip pain after second stage. The median Harris Hip Score (HHS) after first stage was 59, and at 2 years after second stage was 75. For comparison, the 2 year HHS in our patients that had undergone standard cemented femoral revision was 75. Conclusion. A temporary hip implant with high-dose vancomycin cement has improved our clinical management of infected hip replacement after the second stage THR. Patients report hip pain and function that compares to that achieved for standard revision hip replacement

We present the 12 month data on the relatively novel drug Dabigatran Etexilate (Pradaxa), a new oral anticoagulant which was introduced to combat the risk of post operative venous-thromboembolic disease (VTED) in orthopaedic surgery. This drug was introduced at our hospital in March 2010 and we present our modified protocol of: using 5000u subcutaneous Dalteparin whilst in hospital and giving Dabigatran only on discharge, and at a lower dose (150mg compared to 220mg). We carried out a retrospective analysis of the notes and imaging of every patient who underwent elective hip and knee arthroplasty over 12 months since the drug was introduced. We evaluated the rate of VTED complications and the rate of transfusion and bleeding post operatively. The case series of 370 patients showed a 1% risk of deep vein thrombosis with no pulmonary emboli and 1 death due to an unrelated cause. There was a transfusion rate of 11% with 0.5% patients taken back to theatre for evacuation of haematomas. There were no reported adverse effects of Dabigatran. We argue that our modified protocol for this novel drug should be followed as it is both safe and effective for postoperative anticoagulation

Objective

It is known that stress shielding frequently occurs after total hip arthroplasty (THA). However, the status of bone metabolism in stress shielding region is not still clear. ¹⁸F-fluoride positron emission tomography (PET) is a useful tool for the quantitative evaluation of bone metabolism, which uptake relates with the activity of bone formation by osteoblast. In this study, we evaluated the status of bone turnover in stress shielding region using ¹⁸F -fluoride PET.

Introduction

In all traumatic injury there is a clear relationship between the structural tissue damage and resultant disability after recovery. There are no publications that compare significant thoracolumbar osseous injury to non specific soft tissue injury.

Aim. The β-lactam penicillin is often used in the treatment of soft tissue infections and osteomyelitis caused by penicillin susceptible Staphylococcus aureus. Oral antibiotic treatment has been shown to be non-inferior to intravenous (IV) therapy when used during the first 6 weeks in complex orthopedic infections (OVIVA trial). However, the use of oral β-lactams in osteomyelitis treatment remains a topic of debate due to low and variable bioavailability. The aim was to assess the time for which the unbound penicillin concentration exceeded targeted minimum inhibitory concentrations (fT>MIC) in cancellous bone and subcutaneous tissue after IV (penicillin G) and oral (penicillin V) treatment in a porcine microdialysis model. Method. 12 female pigs (75kg) were assigned to standard clinical regimens of either three doses of IV penicillin G (1.2g) or oral penicillin V (0.8g) every 6h over 18h. Microdialysis catheters were placed for sampling in tibial cancellous bone and adjacent subcutaneous tissue. Data was collected in the first dosing interval (0–6h; prophylactic situation) and the third dosing interval (12–18h; assumed steady state). Plasma samples were collected for reference. MIC targets of 0.125μg/mL (Staph. aureus breakpoint), 0.25μg/mL (Strep. Group A, B, C and G breakpoint) and 0.5μg/mL (4xMIC) were applied. Results. For all investigated MIC targets, IV penicillin G resulted in a longer mean fT>MIC in cancellous bone during the first dosing interval, and in both cancellous bone and subcutaneous tissue during the third dosing interval compared to oral penicillin V. Across compartments, mean fT>MIC for IV penicillin G (MIC: 0.125, 0.25 and 0.5μg/mL) were ≥97%, ≥84% and ≥75% during the first dosing interval, and 100%, ≥95% and ≥88%, during the third dosing interval. The mean fT>MIC for oral penicillin V were ≥40%, ≥24% and ≥7% during the first dosing interval, and ≥42%, ≥36% and ≥18% during the third dosing interval. Conclusions. The findings suggest that standard clinical dosing of IV penicillin G provides superior fT>MIC in cancellous bone and subcutaneous tissue compared to oral penicillin V, particularly in the third dosing interval. This emphasizes the importance of appropriate route of administration when applying penicillin treatment. Acknowledgements. Funding was received from The Kirsten and Freddy Johansen Foundation, The Novo Nordisk Foundation, The Beckett Foundation, The Hede Nielsen Family Foundation, King Christian the 10. th. Foundation, The A.P. Møller Foundation, The Dagmar Marshalls Foundation, and The Carl and Ellen Hertz Foundation

Neuromuscular scoliosis patients face rates of major complications of up to 49%. Along with pre-operative risk reduction strategies (including nutritional and bone health optimization), intra-operative strategies to decrease blood loss and decrease surgical time may help mitigate these risks. A major contributor to blood loss and surgical time is the insertion of instrumentation which is challenging in neuromuscular patient given their abnormal vertebral and pelvic anatomy. Standard pre-operative radiographs provide minimal information regarding pedicle diameter, length, blocks to pedicle entry (e.g. iliac crest overhang), or iliac crest orientation. To minimize blood loss and surgical time, we developed an “ultra-low dose” CT protocol without sedation for neuromuscular patients. Our prospective quality improvement study aimed to determine: if ultra-low dose CT without sedation was feasible given the movement disorders in this population; what the radiation exposure was compared to standard pre-operative imaging; whether the images allowed accurate assessment of the anatomy and intra-operative navigation given the ultra-low dose and potential movement during the scan. Fifteen non-ambulatory surgical patients with neuromuscular scoliosis received the standard spine XR and an ultra-low dose CT scan. Charts were reviewed for etiology of neuromuscular scoliosis and medical co-morbidities. The CT protocol was a high-speed, high-pitch, tube-current modulated acquisition at a fixed tube voltage. Adaptive statistical iterative reconstruction was applied to soft-tissue and bone kernels to mitigate noise. Radiation dose was quantified using reported dose indices (computed tomography dose index (CTDIvol) and dose-length product (DLP)) and effective dose (E), calculated through Monte-Carlo simulation. Statistical analysis was completed using a paired student's T-test (α = 0.05). CT image quality was assessed for its use in preoperative planning and intraoperative navigation using 7D Surgical System Spine Module (7D Surgical, Toronto, Canada). Eight males and seven females were included in the study. Their average age (14±2 years old), preoperative Cobb angle (95±21 degrees), and kyphosis (60±18 degrees) were recorded. One patient was unable to undergo the ultra-low dose CT protocol without sedation due to a co-diagnosis of severe autism. The average XR radiation dose was 0.5±0.3 mSv. Variability in radiographic dose was due to a wide range in patient size, positioning (supine, sitting), number of views, imaging technique and body habitus. Associated CT radiation metrics were CTDIvol = 0.46±0.14 mGy, DLP = 26.2±8.1 mGy.cm and E = 0.6±0.2 mSv. CT radiation variability was due to body habitus and arm orientation. The radiation dose differences between radiographic and CT imaging were not statistically significant. All CT scans had adequate quality for preoperative assessment of pedicle diameter and orientation, obstacles impeding pedicle entry, S2-Alar screw orientation, and intra-operative navigation. “Ultra-low dose” CT scans without sedation were feasible in paediatric patients with neuromuscular scoliosis. The effective dose was similar between the standard preoperative spinal XR and “ultra-low dose” CT scans. The “ultra-low dose” CT scan allowed accurate assessment of the anatomy, aided in pre-operative planning, and allowed intra-operative navigation despite the movement disorders in this patient population

Neuromuscular scoliosis patients face rates of major complications of up to 49%. Along with pre-operative risk reduction strategies (including nutritional and bone health optimization), intra-operative strategies to decrease blood loss and decrease surgical time may help mitigate these risks. A major contributor to blood loss and surgical time is the insertion of instrumentation which is challenging in neuromuscular patient given their abnormal vertebral and pelvic anatomy. Standard pre-operative radiographs provide minimal information regarding pedicle diameter, length, blocks to pedicle entry (e.g. iliac crest overhang), or iliac crest orientation. To minimize blood loss and surgical time, we developed an “ultra-low dose” CT protocol without sedation for neuromuscular patients. Our prospective quality improvement study aimed to determine:. if ultra-low dose CT without sedation was feasible given the movement disorders in this population;. what the radiation exposure was compared to standard pre-operative imaging;. whether the images allowed accurate assessment of the anatomy and intra-operative navigation given the ultra-low dose and potential movement during the scan. Fifteen non-ambulatory surgical patients with neuromuscular scoliosis received the standard spine XR and an ultra-low dose CT scan. Charts were reviewed for etiology of neuromuscular scoliosis and medical co-morbidities. The CT protocol was a high-speed, high-pitch, tube-current modulated acquisition at a fixed tube voltage. Adaptive statistical iterative reconstruction was applied to soft-tissue and bone kernels to mitigate noise. Radiation dose was quantified using reported dose indices (computed tomography dose index (CTDIvol) and dose-length product (DLP)) and effective dose (E), calculated through Monte-Carlo simulation. Statistical analysis was completed using a paired student's T-test (α= 0.05). CT image quality was assessed for its use in preoperative planning and intraoperative navigation using 7D Surgical System Spine Module (7D Surgical, Toronto, Canada). Eight males and seven females were included in the study. Their average age (14±2 years old), preoperative Cobb angle (95±21 degrees), and kyphosis (60±18 degrees) were recorded. One patient was unable to undergo the ultra-low dose CT protocol without sedation due to a co-diagnosis of severe autism. The average XR radiation dose was 0.5±0.3 mSv. Variability in radiographic dose was due to a wide range in patient size, positioning (supine, sitting), number of views, imaging technique and body habitus. Associated CT radiation metrics were CTDIvol = 0.46±0.14 mGy, DLP = 26.2±8.1 mGy.cm and E = 0.6±0.2 mSv. CT radiation variability was due to body habitus and arm orientation. The radiation dose differences between radiographic and CT imaging were not statistically significant. All CT scans had adequate quality for preoperative assessment of pedicle diameter and orientation, obstacles impeding pedicle entry, S2-Alar screw orientation, and intra-operative navigation. “Ultra-low dose” CT scans without sedation were feasible in paediatric patients with neuromuscular scoliosis. The effective dose was similar between the standard preoperative spinal XR and “ultra-low dose” CT scans. The “ultra-low dose” CT scan allowed accurate assessment of the anatomy, aided in pre-operative planning, and allowed intra-operative navigation despite the movement disorders in this patient population

Aim. Deadspace is the tissue and bony defect in a surgical wound after closure. This space is presumably poorly perfused favouring bacterial proliferation and biofilm formation. In arthroplasty surgery, an obligate deadspace surrounding the prosthesis is introduced and deadspace management, in combination with obtaining therapeutic prophylactic antibiotic concentrations, is important for limiting the risk of acquiring a periprosthetic joint infection (PJI). This study aimed to investigate cefuroxime distribution to an orthopaedic surgical deadspace in comparison with plasma and bone concentrations during two dosing intervals (8 h × 2). Method. In a setup imitating shoulder arthroplasty surgery, but without insertion of a prosthesis, microdialysis catheters were placed for cefuroxime sampling in a deadspace in the glenohumeral joint and in cancellous bone of the scapular neck in eighteen pigs. Blood samples were collected from a central venous catheter as a reference. Cefuroxime was administered according to weight (20 mg/kg). The primary endpoint was time above the cefuroxime minimal inhibitory concentration of the free fraction of cefuroxime for Staphylococcus aureus (fT > MIC (4 µg/mL)). Results. During the two dosing intervals, mean fT > MIC (4 µg/mL) was significantly longer in deadspace (605 min) compared with plasma (284 min) and bone (334 min). For deadspace, the mean time to reach 4 µg/mL was prolonged from the first dosing interval (8 min) to the second dosing interval (21 min), while the peak drug concentration was lower and half-life was longer in the second dosing interval. Conclusions. In conclusion, weight-adjusted cefuroxime fT > MIC (4 µg/mL) and elimination from the deadspace was longer in comparison to plasma and bone. Our results suggest a deadspace consolidation and a longer diffusions distance, resulting in a low cefuroxime turn-over. Based on theoretical targets, cefuroxime appears to be an appropriate prophylactic drug for the prevention of PJI. Acknowledgments. We would like to thank Department of Clinical Medicine, the surgical research laboratories, Aarhus University Hospital and Department of Clinical Biochemistry, Lillebaelt Hospital, Vejle, Denmark, for supporting this study. This research was funded by Novo Nordisk Foundation, grant number [NNF20OC0062032, 2020]

Our study sought to establish the necessity of prolonged pre-operative antibiotic prophylaxis in patients presenting with zone II and zone V acute flexor tendon injuries (FTI). We hypothesized that a single dose of prophylactic antibiotic was adequate in prevention of post-operative wound infection in acute zone II and V FTI. This was a prospective study of 116 patients who presented with zone II and zone V acute FTI. The study included patients who were 18 years and older. Those with macroscopic contamination, immunocompromised, open fractures, bite injuries, and crush injuries were excluded. Patients were randomised into a group receiving a single dose of prophylactic antibiotic and another group receiving a continuous 8 hourly antibiotic doses until the day of surgery. Each group was subdivided into occupational and non-occupational injuries. Their post-operative wound outcomes were documented 10 – 14 days after surgery. The wound outcome was reported as no infection, superficial infection (treated with wound dressings), and deep infection (requiring surgical debridement). There was 0.9% rate of deep post-operative wound infections, which was a single zone V acute FTI case in a single dose prophylactic antibiotic group. There was a 7.8% superficial post-operative wound infection rate, which was mainly zone II acute FTI in both antibiotic groups. There was a strong association between zone II acute FTI and post-operative wound infection (p < 0.05). There was no association between (antibiotic dosage or place of injury) with post-operative wound infection (p > 0.05). There is no benefit in prescribing prolonged pre-operative antibiotic in patients with acute, simple lacerations to zone II and zone V FTI if there is no macroscopic wound contamination