En bloc resection for primary bone tumours and isolated metastasis are complex surgeries associated with a high rate of adverse events (AEs). The primary objective of this study was to explore the relationship between frailty/sarcopenia and major perioperative AEs following en bloc resection for primary bone tumours or isolated metastases of the spine. Secondary objectives were to report the prevalence and distribution of frailty and sarcopenia, and determine the relationship between these factors and length of stay (LOS), unplanned reoperation, and 1-year postoperative mortality in this population.

This is a retrospective study of prospectively collected data from a single quaternary care referral center consisting of patients undergoing an elective en bloc resection for a primary bone tumour or an isolated spinal metastasis between January 1st, 2009 and February 28th, 2020. Frailty was calculated with the modified frailty index (mFI) and spine tumour frailty index (STFI). Sarcopenia, determined by the total psoas area (TPA) vertebral body (VB) ratio (TPA/VB), was measured at L3 and L4. Regression analysis produced ORs, IRRs, and HRs that quantified the association between frailty/sarcopenia and major perioperative AEs, LOS, unplanned reoperation and 1-year postoperative mortality.

One hundred twelve patients met the inclusion criteria. Using the mFI, five patients (5%) were frail (mFI ³ 0.21), while the STFI identified 21 patients (19%) as frail (STFI ³ 2). The mean CT ratios were 1.45 (SD 0.05) and 1.81 (SD 0.06) at L3 and L4 respectively. Unadjusted analysis demonstrated that sarcopenia and frailty were not significant predictors of major perioperative AEs, LOS or unplanned reoperation. Sarcopenia defined by the CT L3 TPA/VB and CT L4 TPA/VB ratios significantly predicted 1-year mortality (HR of 0.32 per one unit increase, 95% CI 0.11-0.93, p=0.04 vs. HR of 0.28 per one unit increase, 95% CI 0.11-0.69, p=0.01) following unadjusted analysis. Frailty defined by an STFI score ≥ 2 predicted 1-year postoperative mortality (OR of 2.10, 95% CI 1.02-4.30, p=0.04).

The mFI was not predictive of any clinical outcome in patients undergoing en bloc resection for primary bone tumours or isolated metastases of the spine. Sarcopenia defined by the CT L3 TPA/VB and L4 TPA/VB and frailty assessed with the STFI predicted 1-year postoperative mortality on univariate analysis but not major perioperative AEs, LOS or reoperation. Further investigation with a larger cohort is needed to identify the optimal measure for assessing frailty and sarcopenia in this spine population.

Prolonged length of stay (LOS) is a significant contributor to the variation in surgical health care costs and resource utilization after elective spine surgery. The primary goal of this study was to identify patient, surgical and institutional variables that influence LOS. The secondary objective is to examine variability in institutional practices among participating centers.

This is a retrospective study of a prospectively multicentric followed cohort of patients enrolled in the CSORN between January 2015 and October 2020. A logistic regression model and bootstrapping method was used. A survey was sent to participating centers to assessed institutional level interventions in place to decrease LOS. Centers with LOS shorter than the median were compared to centers with LOS longer than the median.

A total of 3734 patients were included (979 discectomies, 1102 laminectomies, 1653 fusions). The median LOS for discectomy, laminectomy and fusion were respectively 0.0 day (IQR 1.0), 1.0 day (IQR 2.0) and 4.0 days (IQR 2.0). Laminectomy group had the largest variability (SD=4.4, Range 0-133 days). For discectomy, predictors of LOS longer than 0 days were having less leg pain, higher ODI, symptoms duration over 2 years, open procedure, and AE (p< 0.05). Predictors of longer LOS than median of 1 day for laminectomy were increasing age, living alone, higher ODI, open procedures, longer operative time, and AEs (p< 0.05). For posterior instrumented fusion, predictors of longer LOS than median of 4 days were older age, living alone, more comorbidities, less back pain, higher ODI, using narcotics, longer operative time, open procedures, and AEs (p< 0.05). Ten centers (53%) had either ERAS or a standardized protocol aimed at reducing LOS.

In this study stratifying individual patient and institutional level factors across Canada, several independent predictors were identified to enhance the understanding of LOS variability in common elective lumbar spine surgery. The current study provides an updated detailed analysis of the ongoing Canadian efforts in the implementation of multimodal ERAS care pathways. Future studies should explore multivariate analysis in institutional factors and the influence of preoperative patient education on LOS.

Frailty has been shown to be a risk predictor for peri-operative adverse events (AEs) in patients undergoing various type of spine surgery. However, its relationship with Patient Related Outcome Measures (PROMS) remains unknown. The primary objective of this study was to determine the impact of frailty on PROMS in patients undergoing surgery for thoraco-lumbar degenerative conditions. The secondary objective was to determine the association between frailty and baseline PROMS.

This is a retrospective study of a prospective cohort of patients >55 years old who underwent surgery between 2012 and 2018. Patient data and PROMS (EQ-5D, SF-12, ODI, back and leg pain NRS) were extracted from the Canadian Spine Outcomes and Research Network registry for a single academic centre. Frailty was retrospectively calculated using the modified frailty index (mFI) and patient were classified as frail, pre-frail and non-frail. Patient characteristics and outcomes were analyzed using ANOVA or Kruskal-Wallis test for continuous variables and Chi square or Fisher's exact test for proportions. A generalized estimating equations (GEEs) regression model was used to assess the association between patients' baseline frailty status and PROMs measures at three and 12 months.

293 patients were included with a mean age of 67 ± 7 years. Twenty-two percent of the patients (n= 65) were frail, 59 % (n=172) were pre-frail and 19% (n=56) were non-frail. At baseline, the three groups had similar PROMS, except for the PCS which was worse in the frail group (mean difference [95% CI], −4.9 [−8.6;-1.1], p= 0.0083). The improvement in the EQ-5D, PCS, MCS, ODI, back and leg pain NRS scores was not significantly different between the three groups (p> 0.05). The was no difference in the evolution of the PROMS at three and 12 months between the three groups (p> 0.05).

Although frailty is a known predictor of AEs, it does not predict worse PROMS after spine surgery in that population. At baseline, non-frail, pre-frail and frail patients have similar PROMS.

Pedicle screw fixation is a technically demanding procedure with potential difficulties and reoperation rates are currently on the order of 11%. The most common intraoperative practice for position assessment of pedicle screws is biplanar fluoroscopic imaging that is limited to two- dimensions and is associated to low accuracies. We have previously introduced a full-dimensional position assessment framework based on registering intraoperative X-rays to preoperative volumetric images with sufficient accuracies. However, the framework requires a semi-manual process of pedicle screw segmentation and the intraoperative X-rays have to be taken from defined positions in space in order to avoid pedicle screws' head occlusion. This motivated us to develop advancements to the system to achieve higher levels of automation in the hope of higher clinical feasibility.

In this study, we developed an automatic segmentation and X-ray adequacy assessment protocol. An artificial neural network was trained on a dataset that included a number of digitally reconstructed radiographs representing pedicle screw projections from different points of view. This model was able to segment the projection of any pedicle screw given an X-ray as its input with accuracy of 93% of the pixels. Once the pedicle screw was segmented, a number of descriptive geometric features were extracted from the isolated blob. These segmented images were manually labels as ‘adequate’ or ‘not adequate’ depending on the visibility of the screw axis. The extracted features along with their corresponding labels were used to train a decision tree model that could classify each X-ray based on its adequacy with accuracies on the order of 95%.

In conclusion, we presented here a robust, fast and automated pedicle screw segmentation process, combined with an accurate and automatic algorithm for classifying views of pedicle screws as adequate or not. These tools represent a useful step towards full automation of our pedicle screw positioning assessment system.

Purpose: A systematic review of Health Related Quality of Life Outcomes(HRQOL) in metastatic disease of the spine and content validation of a new Spine Oncology Study Group Outcomes Questionnaire(SOSGOQ). To identify HRQOL questionnaires previously reported for spinal metastases and to validate the content of the new SOSGOQ based on the International Classification of Function and disability(ICF).

Method: A systematic review identified 141 studies. Reported outcome tools were enumerated. The most commonly utilized (ESAS, Karnofsky Scale and ODI) and the SOSGOQ were linked to the ICF. Descriptive statistics examined the frequency and specificity of the ICF linkage. Linkage reliability was evaluated by inter-investigator percentage agreement.

Results: The SOSGOQ contains 56 concepts, with all 4 domains of the ICF represented. 4 concepts could not be linked. There was 100% inter-observer agreement(IOA) for total number of concepts and for those ‘not covered’. 100% of concepts had ‘First and Second’ level linkage. 100% IOA exists at both ‘Component’ and “First Level’ linkage. There was 96.1% IOA at ‘Second’ Level. 33 concepts linked to Third Level with 96.9% IOA. 10 concepts linked at the Fourth Level with 100% IOA.

Conclusion: The SOSGOQ includes all domains relevant for measurement of function and disability and it’s content validity is confirmed by linkage with the ICF. This new questionnaire has superior content capacity to measure disease burden of patients with metastatic disease of the spine than any instruments previously identified in the literature.

Purpose: There is very little evidence to guide treatment of patients with spinal surgical site infection (SSI) who require irrigation and debridement (I& D) with respect to need for single or multiple I& D’s. The purpose of this study is to build a predictive model which stratifies patients with spinal SSI to determine which patients will go on to need single versus multiple I& D.

Method: A consecutive series of 128 patients from a tertiary spine center (collected from 1999–2005) who required I& D for spinal SSI, were studied based on data from a prospectively collected outcomes database. Over 30 variables were identified by extensive literature review as possible risk factors for SSI, and tested as possible predictors of risk for multiple I& D. Logistic regression was conducted to assess each variable’s predictability by a “bootstrap” statistical method. Logistic regression was applied using outcome of I& D – single or multiple as the “response”.

Results: 24/128 patients required multiple I& D. Primary spine diagnosis was approximately represented by ¼ trauma, ¼ deformity, ¼ degenerative and ¼ oncology/inflammatory/other. Six predictors: spine location, medical comorbidities, microbiology of the SSI, presence of distant site infection (ie. UTI or bacteremia), presence of instrumentation and bone graft type, proved to be the most reliable predictors of need for multiple I& D. Internal validation of the predictive model yielded area under the curve (AUC) of .84

Conclusion: Infection factors played an important role in need for multiple I& D. Patients with +MRSA culture or those with distant site infection such as bacteremia with or without UTI or pneumonia, were strong predictors of need for multiple I& D. Presence of instrumentation, location of surgery in the posterior lumbar spine and use of non-autograft bone predicted multiple I& D. Diabetes also proved to be the most significant medical comorbidity for multiple I& D.

Purpose: The decision of whether or not an injury to the sub-axial cervical spine needs operative management often hinges on the stability of the spine. The posterior Ligamentous Complex (PLC) is one of the primary soft tissue stabilizers of the cervical spine. Fat-saturated T2-wieghted MRI sequences are able to demonstrate soft tissue injury to the cervical spine. No studies to date have assessed the ability of MRI to accurately and reliably demonstrate PLC disruption in the sub-axial cervical spine.

Method: Forty-nine consecutive patients aged 14–85 years presenting to the two participating institutions with injury between C3 and T1 who required posterior surgery as part of their management were prospectively enrolled in the study. All patients had radiographs, CT, and MRI scans preoperatively, which were reviewed by a Neuroradiologist, and the treating surgeon separately. Their posterior intraoperative findings were then recorded by the treating surgeon and his assistant. Statistical analysis included Spearman’s rank order correlation, and Cohen’s kappa score.

Results: There was a moderate level of agreement between the radiologist’s interpretation of the preopera-tive MRI and the surgeon’s intraoperative findings for the supraspinous and intraspinous ligaments, (kappa.49 & .48 respectively). A fair level of agreement was found for the ligamentum flavum, left and right facet capsules, and the cervical fascia (kappa scores.31,.30,.30,.39 respectively).

Conclusion: MRI has a high sensitivity (78.6% to 100%) for detecting cervical PLC injury but a low specificity (53.6% to 75%). On its own MRI is not a useful tool for diagnosing cervical spine PLC injury. The clinician should be aware of the relatively high rate of false positive PLC injury diagnosis with MRI.

Purpose: Apoptosis of osteoblasts and osteoclasts regulates bone homeostasis. Vertebral osteoporotic insufficiency fractures are characterised by pathological rates of osteoblast apoptosis. Skeletal injury in humans results in ‘angiogenic’ responses primarily mediated by vascular endothelial growth factor(VEGF), a protein essential for bone repair in animal models. Osteoblasts release VEGF in response to a number of stimuli and express receptors for VEGF in a differentiation dependent manner. This study investigates the putative role of VEGF in regulating the lifespan of primary human vertebral osteoblasts (PHVO) in-vitro.

Method: PHVO were cultured from biopsies taken at time of therapeutic vertebroplasty and were examined for VEGF receptors. Cultures were supplemented with VEGF(0–50ng/mL), a neutralising antibody to VEGF, mAB VEGF(0.3ug/mL) and Placental Growth Factor (PlGF), an Flt-1 receptor-specific VEGF ligand(0–100 ng/mL) to examine their effects on mineralised nodule assay, alkaline phosphatase assay and apoptosis. The role of the VEGF specific antiapoptotic gene target BCl2 in apoptosis was determined.

Results: PHVO expressed functional VEGF receptors. VEGF 10 and 25 ng/mL increased nodule formation 2.3- and 3.16-fold and alkaline phosphatase release 2.6 and 4.1-fold respectively while 0.3ug/mL of mAB VEGF resulted in approx 40% reductions in both. PlGF 50ng/mL had greater effects on alkaline phosphatase release (103% increase) than on nodule formation (57% increase). 10ng/mL of VEGF inhibited spontaneous and pathological apoptosis by 83.6% and 71% respectively, while PlGF had no significant effect. Pretreatment with mAB VEGF, in the absence of exogenous VEGF resulted in a significant increase in apoptosis (14 versus 3%). BCl2 transfection gave a 0.9% apoptotic rate. VEGF 10 ng/mL increased BCl2 expression four fold while mAB VEGF decreased it by over 50%.

Conclusion: VEGF is a potent regulator of osteoblast life-span in-vitro. This autocrine feedback regulates survival of these cells, mediated via the KDR receptor and expression of BCl2 antiapoptotic gene. This mechanism may represent a novel therapeutic model for the treatment of osteoporosis.

Purpose: To evaluate the demographics, presentation, treatment and outcomes of spinal infection in a population of Intravenous Drug Users.

Method: Data on all patients with pyogenic spinal infection presenting to a quaternary referral center was obtained from a prospectively maintain database.

Results: Over the five-year study period, there were 102 patients treated for Primary Pyogenic Infection of the Spine of which 51 were Intravenous Drug Users (IVDU). Of this IVDU group there were 34 males. Mean age was 43 years (range 25 – 57). Twenty-three had HIV, 43 Hepatitis C and 13 Hepatitis B. All were using cocaine, 26 were also using Heroin and 44 more than three recreational drugs. Thirty patients presented with axial pain with a mean duration of 51 days (range 3–120). Thirty-one were ASIA D or worse with eight ASIA A. Mean Motor Score of patients with deficit was 58.6. Most common ASIA Motor Levels were C4 and C5. Mean duration of neurological symptoms was seven days (range 1–60). Blood parameters on admission were in keeping with sepsis in immunocompromised patients. None had previous surgery for spinal infection. Twenty-sex were receiving IV antibiotics for known spinal infection. 44 patients were treated surgically. 32 had infection of the cervical spine, 9 Thoracic and 3 Lumbar. 22 had a posterior approach alone, 13 had anterior only while 9 required combined. Mean operative time was 263 mins (range 62 – 742). 13 required tracheostomy. 7 required early revision for hardware failure and 2 for surgical wound infection. Mean duration of antibiotic treatment was 49 days (range 28–116). 26 patients had single agent therapy. 17 had MSSA and 17 MRSA. At discharge 28 patients had neurological improvement (mean 20 ASIA points, range 1–55), 11 had deterioration (mean 13, range 1–50) and 5 were unchanged. There were no in-hospital deaths. At 2 years after index admission 13 patients were dead and none were attending the unit for follow-up.

Conclusion: Primary pyogenic spinal infection in IVDU’s typically presents with sepsis and acute cervical quadriplegia. Surgical management must be prompt and aggressive with significant neurological improvement expected in the majority of patients.

Purpose: Prospective Observational Population Study to describe the incidence, demographics and pattern of spinal cord injury in British Columbia, Canada, for 10 years to 2004.

Method: Systematic analysis of prospectively collected spine registry data (Vertebase) at Vancouver General Hospital, B.C., Canada from 1995–2004.

Results: During the 10-year study period the 938 patients were admitted with a traumatic spinal cord injury. The Annual Population-Standardized Incidences ranged from 19.94 to 27.27 per million, with a median incidence of 23.34/million and with no significant change over the study period. The mean age was 39.7 years (34.73 in 1995 and 42.1 in 2004, p< 0.05) with a range of 16–92 years. 79.74 % were males. 48.2% of patients were AISA A on admission, of which 48% were quadraparetic. The most common levels of spinal cord injury were C5 (17.3%), C6 (10%), T1 (9.4%), T12 (5.8%). The Mean ASIA score was 50.22 with a range from 0–100. 19.8% of patients had a GCS£13. The mean ISS was 26.02, range of 0 – 75. Motor vehicle collisions and falls were responsible for 59% and 30% of admissions respectively. Mean length of in-hospital stay was 34 days, ranging from 1 – 275 days. In hospital mortality rate was 2.9%. ASIA Grade, Total Motor Score and anatomical level of injury all correlated directly with Length of stay (p< 0.0001).

Conclusion: Acute Traumatic Spinal Cord Injury remains a major cause of significant morbidity among young males. The incidence appears to be increasing in the elderly. Modern multidisciplinary care has greatly reduced the associated acute mortality. Despite multiple prevention strategies the Annual Population-Standardized Incidence remained unchanged over the study period.

Aims: A retrospective review of all periacetabular osteotomies (PAO) performed at a general elective orthopaedic Hospital over a 7-year period. To assess the clinical, functional and radiographic outcome associated with PAO when introduced as a new procedure to a non-super-specialised regional centre.

Methods: A retrospective review of 85 PAOs performed on 79 patients at Cappagh Hospital between 1/4/1998 and 1/4/2005. The medical records and radiographic images of all patients were reviewed. Clinical follow-up evaluations were also performed.

Results: 85 PAOs were performed on 79 patients. Mean age at time of surgery was 22.9 years (range, 14–41 years) with an increased preponderance of females (F:M=10:1) and right sided hip involvement (R:L=1.1:1). The mean Merle D’Aubigne and Postel hip score increased from 12.4 (range 9–14) preoperatively to 16 (range 11–18) postoperatively (P< 0.0001). The average lateral center edge angle increased from 5° preoperatively to 26° postoperatively (P< 0.0001). The anterior center edge angle averaged 6.6° preoperatively and improved to 34.4° postoperatively (P < 0.0001). The acetabular index angle decreased from an average of 24.8° preoperatively to 8.4° postoperatively (P< 0.0001). At clinical follow-up, 77% of patients had no/mild pain, 30% of patients had a limp and 64% of patients were unlimited in physical activity.

Conclusions: The short term results in this group of patients treated with PAO show reliable radiographic correction of deformity and improved clinical scores. We suggest that PAO may safely be carried out at a non-super-specialized institution provided the surgeons have sufficient experience and patients are selected appropriately.

The purpose of this study was to review the early results of a consecutive series of patients undergoing periac-etabular osteotomy (PAO) at Cappagh National Orthopaedic Hospital. The procedure was first carried out in 1998, and a total of 85 PAOs have been performed in 79 patients. The mean follow-up was 42 months (range 6-84 months). There were 72 females and 7 males with a mean age at the time of the operation of 22.9 years (range, 14-41 years). The preoperative diagnosis was developmental hip dysplasia in 80 hips, Legg-Calve-Perthes disease in one hip, congenital coxa vara in three hips, and slipped capital femoral epiphysis in one hip. The average Merle d’Aubigne score increased from 12.4 points preoperatively to 16 points at latest followup. The lateral center edge angle of Wiberg was between – 20 and +28 before surgery and was improved from 12 to 48 (average 30 degrees) following PAO. While, the anterior center edge angle of Lequesne and de Seze was between – 22 and +35 preoperatively and was improved by an average of 28 degrees (range, 17 – 40) postoperatively. The acetabular index angle decreased from an average of 24.8 preoperatively to 8.4 postoperatively. Clinical follow-up revealed that 77% of patients had no or mild pain, 33% of patients had a limp and 64% of patients were unlimited in physical activity, representing a markedly improved clinical outcome. Four patients underwent subsequent total hip arthroplasty. The short term results in this group of patients treated with PAO show reliable radiographic correction of deformity and improved clinical scores. The study reflects the learning curve associated with performing this procedure and the results that can be expected with a smaller clinical case-load than described in previous studies. We suggest that PAO may safely be carried out at a non-super-specialized institution provided the surgeons have sufficient experience and patients are selected appropriately.

Introduction: The limping child poses a diagnostic challenge. The purpose of this study was to create a clinically useful algorithm of presenting variables to allow the exclusion of ‘musculoskeletal sepsis’ as a differential diagnosis in the child presenting with a limp.

Materials & Methods: This study represents the data collected on all limping children admitted to our centre over a 3-year period. Analysis was based on 229 admissions. Comparison was made between the group with septic arthritis or osteomyelitis and the group without infection, using univariate analysis. With logistic regression analysis, a model consisting of three independent multivariate predictors was constructed, to exclude infection.

Results: Patients with septic arthritis or osteomyelitis differed significantly from patients without infection with regard to duration of symptoms, presence of constitutional symptoms, temperature, white cell count and erythrocyte sedimentation rate (ESR), (p-values < 0.05). Multivariate analysis demonstrated that the best model to describe our patient population was based on three variables: duration of symptoms between 1 and 5 days, temperature > 37.0°C and ESR > 35mm/hr. When all three variables were present, the predicted probability of musculoskeletal infection was 0.66. When none of the three were present, the predicted probability of infection was 0.01.

Discussion: Diagnosis of septic arthritis or osteomyelitis is especially difficult in the early phase and there is no single variable that can serve as a definitive test. The significance of constitutional symptoms and duration of symptoms on univariate analysis emphasises the importance of careful history taking. C-reactive protein, while considered for inclusion, was excluded due to its limited availability at our institution.

Conclusion: The multivariate model enables us to rule out musculoskeletal infection with 99% certainty in limping children with none of these three presenting variables.

Background: Aseptic loosening remains the most common cause of failure of total hip arthroplasty. Its pathogenesis is based upon the generation of wear debris particles which trigger synovial macrophage activation.

Statins, inhibitors of 3-hydroxy-3 methylglutaryl coenzyme A (HMG-Co-A) reductase, have revolutionised the treatment of hypercholesterolaemia. More recently statins have been shown to have potent anti inflammatory effects. We investigated the effects of cerivastatin in attenuating the activation of human macrophages by polymethylmethacrylate (PMMA) particles.

Methods: Polymethylmethacrylate-particle-stimulated human macrophages were cultured in vitro with cerivastatin at 75 and 150... mols/litre. TNF-α (tumour necrosis factor alpha) and MCP-1 (monocyte chemotactic protein) expression were determined using ELISA. An ERK1/2 inhibitor, UO126 was utilised to identify the mitogen activated protein kinase (MAP-Kinase) pathway involved and western blotting was used to demonstrate the effect of Cerivastatin on this pathway.

Results PMMA-stimulated TNF-α and MCP-1 expression was consistently attenuated by cerivastatin therapy.

PMMA activation was attenuated by the ERK1/2 inhibitor, UO126.

Western blotting confirmed ERK downregulation by cerivastatin, establishing a mechanism for its anti-inflammatory effects.

Conclusion: We have demonstrated the beneficial effects of statins in suppressing particle mediated activation of macrophages and the potential to prevent or treat periprosthetic osteolysis.

Introduction: Bone Morphogenic Proteins (BMP’s) are a family of bone-matrix polypeptides isolated from a variety of mammalian species. Implantation of osteogenic proteins induces a sequence of cellular events that leads to the formation of new bone.

Recombinant human osteogenic protein-1 (rhOP1 or BMP-7) has now been produced and is commercially available.

Rationale: OP.1 has been used in our centre since early 2003 and we now report on our experience with its use in the treatment of fracture non unions in a general orthopaedic trauma setting.

Methodology/Results: OP1 has been used in 19 fracture non unions, the commonest site being the tibia but also in the humerus and forearm. Five of these cases had previous autologous bone grafting. There was one case of deep MRSA infection in a proximal humerus fracture. There were no complications associated with the use of OP1 and specifically there were no instances of symptomatic heterotopic bone formation. Eighteen fractures went on to clinical and radiological union.

Conclusions: Autogenous bone is the current standard in the management of fracture non union because of its high osteogenic potential and biocompatibility. Donor site morbidity and quantity remain drawbacks. The use of OP.1 in the treatment of tibial non unions is well documented in the literature but there is little written about its use in other sites.

We are encouraged by our early experiences with the use of OP1 in numerous anatomical sites and apart from issues of cost would see great potential for further use.

Background Joint replacement remains the most effective healthcare measure in improving patient health related quality of life (HRQOL) and pain incompatible with normal daily living remains the primary indication for both hip and knee arthroplasty. Quality of life outcome and patient satisfaction after total hip arthroplasty are complex phenomena and many confounding determinants have been identified. Degenerative disease of the hip joint may present with variable patterns of pain referral in the lower limb. However the effect of varied pain referral patterns on patient outcome and satisfaction after total hip arthroplasty has not previously been examined. Methods From 2000 to 2003, 236 eligible patients scheduled to undergo primary total hip arthroplasty were prospectively enrolled. The principle pain referral pattern (as hip, thigh or knee) was identified in all patients. HRQOL was examined using the Harris Hip score (HHS), the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) and the 36-Item Short-Form Health Survey (SF-36) pre-operatively, 1 year and 2 years postoperatively and with the HHS at 3 months postoperatively. All patients were followed up for a minimum of 2 years. Results The frequency of the pain referral distributions were; hip pain 41%, knee pain 32% and thigh pain 27%. Patients in all groups were comparable preoperatively with respect to age; HHS, and both mean and domain specific WOMAC and SF-36 scores. The mean duration of symptoms was significantly greater in patients with knee pain when compared to the remaining two pain patterns. All patients demonstrated as expected improvements in HHS, SF-36 and WOMAC scores after surgery. At all times postoperatively there were significant differences in mean HHS and mean and domain specific WOMAC and SF-36 scores between patients with hip or thigh pain and those with knee pain (p< 0.001). While notable, differences between hip and thigh pain were not as consistent however. Conclusions Pre-operative pain referral patterns of hip arthritis determine patient outcome and satisfaction after total hip arthroplasty, as measured using validated HRQOL scoring systems. Level of evidence Level I-1 (Prognostic Study-Investigating the Outcome of Disease. Prospective study).

Background Apoptosis of osteoblasts and osteoclasts regulates bone homeostasis. Skeletal injury in humans results in angiogenic responses primarily mediated by vascular endothelial growth factor(VEGF), a protein essential for bone repair in animal models. Osteoblasts release VEGF in response to a number of stimuli and express receptors for VEGF in a differentiation dependent manner. This study investigates the putative role of VEGF in regulating the lifespan of primary human osteoblasts(PHOB) in vitro.

Methods PHOB were examined for VEGF receptors. Cultures were supplemented with VEGF(0–50ng/mL), a neutralising antibody to VEGF, mAB VEGF(0.3ug/mL) and Placental Growth Factor (PlGF), an Flt-1 receptor-specific VEGF ligand(0–100 ng/mL) to examine their effects on mineralised nodule assay, alkaline phosphatase assay and apoptosis.. The role of the VEGF specific antiapoptotic gene target BCl2 in apoptosis was determined.

Results PHOB expressed functional VEGF receptors. VEGF 10 and 25 ng/mL increased nodule formation 2.3- and 3.16-fold and alkaline phosphatase release 2.6 and 4.1-fold respectively while 0.3ug/mL of mAB VEGF resulted in approx 40% reductions in both. PlGF 50ng/mL had greater effects on alkaline phosphatase release (103% increase) than on nodule formation (57% increase). 10ng/mL of VEGF inhibited spontaneous and pathological apoptosis by 83.6% and 71% respectively, while PlGF had no significant effect. Pretreatment with mAB VEGF, in the absence of exogenous VEGF resulted in a significant increase in apoptosis (14 vs 3%). BCl2 transfection gave a 0.9% apoptotic rate. VEGF 10 ng/mL increased BCl2 expression 4 fold while mAB VEGF decreased it by over 50%.

Conclusions VEGF is a potent regulator of osteoblast lifespan in vitro. This autocrine feedback regulates survival of these cells, mediated via the KDR receptor and expression of BCl2 antiapoptotic gene.

Management of symptomatic residual acetabular dysplasia in adolescence and early adulthood remains a major therapeutic challenge. At our unit the two senior authors review all patients preoperatively and simultaneously perform each procedure. In the four years from 1998 forty-three Bernese osteotomies were performed in 40 patients with residual acetabular dysplasia. The mean average age at surgery was 21 years (range 12 – 43 years) and there were 34 female patients. The indication for surgery was symptomatic hip dysplasia (all idiopathic but for one male with a history of slipped capital femoral epiphysis) presenting with pain and restricted ambulation. 4 patients had previous surgery on the affected hip (2 Salter’s osteotomy, one Shelf procedure and one proximal femoral osteotomy). 27.5% of patients had symptomatic bilateral disease. 42% of patients had Severin class IV or V dysplasia at presentation. 100% of patients had preservation of the hip joint at last follow-up evaluation (mean 2.4 years), with excellent results in 82%, an average post-operative Harris hip score of 96, and an average d’Aubigne hip score of 16.1. The mean post-operative improvements in radiographic measures were as follows: Anterior centre edge angle +19.4°, Lateral centre angle +25.8°, Acetabular Index – 10.7°. Head to Ischial distance – 7.3mm. Surgical operative time decreased from 128 minutes to 43 minutes from the first to the most recent case. Average blood loss has reduced from 1850mls to 420mls over the four years experience. Predonation of 2 units of blood requested from all patients with baseline hemoglobin of > 12g/dl. When combined with intraopera-tive cell salvage the need for transfusion of homologous blood has been eliminated. All complications occurred in the first 9 patients: (one major – iliac vein injury requiring no further treatment; four moderate – lateral cutaneous nerve injuries; four minor – asymptomatic heterotopic ossification). Our experience confirms that the Ganz periacetabular osteotomy is an efficacious procedure for the treatment of the residually dysplastic hip, providing excellent clinical results, where early intervention is the key to improved outcome. It is a technically demanding procedure with a significant early learning curve and we believe that a two

Background: By the end of the current Bone and Joint Decade (2000–2010) the World Health Organisation predicts that 55% of post-menopausal women will have osteoporosis, as defined by fragility fracture and / or BMD. Volume aside, fragility fractures also represent a significant technical challenge in operative care. Current aggressive medical management is aimed to minimize the resource impact of this pandemic.

Study Design: This prospective study of 3000 consecutive fractures treated in a Level 1 trauma unit identified 977 fragility fractures requiring operative management, 803 of which were in patients over the age of 65 years. In every case the GP was informed of the diagnosis of osteoporosis and appropriate recommendations were made regarding medical management. We present the demographic features of this population and the resource impact of their management. We also examine the outcome of our efforts to improve care of the elderly with osteoporotic fractures, as all GP’s were contacted 6 months following discharge to determine the uptake of medical treatment as recommended.

Materials and Methods: Our computerized operative database was utilized to prospectively collect demographic and operative data on all 977 patients. All medical charts were examined to identify medications on admission, GP contact details and other relevant information. GP’s were contacted by telephone and post to determine patient 6-month mortality and the uptake in the use of recommended medication. Data represents the mean ± SD.

Results: Of the 803 patients over the age of 65 years, the average age was 80.5 ± 7.5 years, with a 75% female preponderance. 14% of these had had a previous wrist or vertebral insufficiency fracture, while 2.2% had a previous contralateral hip fracture. Hip fractures accounted for 70% (566 patients) of fragility fractures with 25% AMP, 24% Bipolar, 51% DHS. There were 121 wrist fractures. On admission 23% of hip fracture patients were resident in a Nursing Home. Despite the relatively large number with previous fracture (16.2%) only 3.4% were taking calcium / vitamin D supplementation while only 2.1% were on anti-resorptive therapy, eg a bisphosphonate. The median interval between admission and operation was 1 calendar day with a range of 1–10 days. 57% of all cases were performed outside of routine trauma lists. The average length of stay for this hip fracture population was 11.5 days with a further 16.5 days spent at a step down facility. Only 14.8% went directly home. Of 240 GP’s contacted, 74% replied resulting in complete follow-up data on 730 patients. The inpatient mortality rate was 5.8% while that at 6 months follow up was 19%. By this time 54% of hip fracture patients were living in Nursing Homes. The number of patients taking only calcium / vitamin D was 4%, a bisphosphonate alone 6%, while the use of both had risen dramatically to 16%.

Conclusions: To our knowledge this is the largest reported study documenting the epidemiology, demography and short-term follow-up of hip fractures in an elderly Irish population. Such data is essential to appropriately plan for the impending national health crisis consequent to the predicted dramatic rise in the elderly population with bone fragility. In a short time, we have achieved significant success in improving awareness and treatment of osteoporosis in the elderly following hip fracture.

Aims: Circulating endothelial precursor cells (CEPs) are thought to play a role in angiogenesis. We investigated the angiogenic stress of musculoskeletal trauma on CEP kinetics in trauma patients and their bone marrow progenitor populations in a murine model. Methods: Peripheral blood mononuclear cells (PB-MNCs) were isolated from patients (n=12) on consecutive days following closed lower-limb diaphyseal fractures. CEP levels, deþned by the surface expression patterns of VEGFR2, CD34 and AC133 were determined and cytokine analysis of collected serum was performed. Bonemarrow precursors deþned byLy-6A/E and c-Kit expression were harvested following the traumatic insult from the murine model and quantiþed on ßow cytometry. Human and murine progenitor populations were cultured on þbronectin and examined for markers of endothelial cell lineage (Ulexeuropaeus- agglutinin-1 binding and acetylated-LDL uptake) and cell morphology. Statistical analysis was performed using variance analysis. Results: A consistent increase in human CEPs levels was noted within 72 hours of the initial insult, the percentage increase over day 1 reaching 300% (p=0.008) and returning to normal levels by day 10. Murine bone marrow precursors were mobilisd within 24 hrs peaking at 48hrs (900% p=0.035). On culture, morphologically characteristic endotheliallike cells binding UEA-1 and incorporating LDL were identiþed. Serum VEGF levels increased signiþcantly within 24 hrs of the insult, (p=0.018) preceeding the peak in CEP mobilisation. Conclusion: We propose that musculoskeletal trauma through the release of chemokines such as VEGF, promotes rapid mobilisation of CEPs from born marrow, which have the potential to contribute to reparative neovascularisation. Strategies to enhance CEPs kinetics may accelerate this process and offer a therapeutic role in aberrant fracture healing.