Internal fixation for supracondylar fracture of the femur after total knee arthroplasty (TKA) is technically difficult and troublesome because the distal bony fragment is often osteoporotic and too small to fix by screws or K-wires. In addition, the femoral component interferes with the screws or K-wires to be inserted from distal direction for fixation of the fracture. Patients and Methods. Four knees in 4 patients (all female; average age, 81.5 +/− 2.6 years) with the fracture after TKA were treated with revision TKA. Follow-up period was between six months and 3 years postoperatively. Operative technique. All operations were performed with the patient in the supine position and using a curved anterior (Payer) approach with or without osteotomy of the tuberositas tibiae. The femoral component was removed with detachment from fractured bony fragments. New femoral component with long stem for fixation of the fracture were inserted with bone cement in each case. Post-operative regimen. On the third postoperative day the patient began flexion and exension exercise of the operated knee joint with a rehabilitation programmed by clinical path under the supervision of a physiotherapist. The use of crutches for ambulation was begun on the 10. th. to 14. th. postoperative day, and the extent of weight bearing was allowed individually according to the stability of the fixation of the fracture. The time to full weight bearing in each patient was 3 to 8 weeks postoperatively. Results. Postoperative courses were uneventful in all of the cases. The supracondylar fracture of the femur was rigidly fixed and healed radiographically within 8 weeks postoperatively in each case. The JOA scores were improved in all od the cases. The mean Japanese Orthopaedic Association (JOA) scores for the knees improved to 90 points postoperative. No femoral components had definite radiographic evidence of loosening and were re-revised. Discussion. In the current study of short-term results of revision total knee arthroplasty for treatment of supracondylar fracture of the femur after total knee with osteoporosis, the component have shown to remain stable in weight bearing conditions and functioned well. Fracture healing and good clinical outcome, evaluated according to the JOA score, were achieved in all cases. Longer-term outcome should be the subject of further investigation. Conclusion. The revision TKA was a successful method for treatment of the supracondylar fracture after TKA

Introduction. Total hip arthroplasty (THA) using short design stem is surging with increasing movement of minimally invasive techniques. Short stems are easier to insert through small incisions preserving muscles. We have used these types of short stems since 2010. Almost all of the patients have shown good clinical results. However, two patients developed fatigue fractures on femurs post operatively. We have reviewed the clinical and radiographic results of these patients. Patients and methods. From April 2010, we have performed 621 THAs with short design stems, Microplasty. R. , Biomet, using a muscle preservation approach, the Direct Anterior Approach (DAA). The age ranged from 31 to 88 years old. Case1: 56y.o. male, BMI 23.1kg/m. 2. Preoperative diagnosis was bilateral osteoarthritis. Simultaneous THAs were performed on bilateral hips. He was allowed to bear as much weight as he could tolerate using an assistive device immediately after surgery, and followed standard hip precautions for the first 3 weeks. He was discharged from hospital seven days after surgery and returned to his job two weeks after surgery. He noticed sudden left thigh pain three weeks after surgery without any obvious cause. Crutches were recommended to partially bear his weight. Six weeks after surgery, a fracture line became visible on the radiographs and new callus formation also became visible. Three months after surgery, he felt no pain and was able to walk without any crutches. Case2: 66y.o. female, BMI 27.5 kg/m. 2. Preoperative diagnosis was bilateral osteoarthritis. THAs were performed on the hips at a six month interval. The right hip was operated on first, followed by the left hip. She was discharged from hospital four days after surgery and returned to her job six weeks after surgery. Two months later after left hip surgery, she suddenly felt pain on her left femur without any obvious cause, and was unable to walk. Three weeks later, X-rays showed fatigue fracture lines and new callus formations. After two or three months using crutches, her pain improved and X-rays showed good callus formation and no stem subsidence. Discussions. Several reports showed insufficiency fractures of the pelvis following THA. But most of them occurred due to repetitive stress on fragile bones. But our cases showed no evidence of osteoporosis. They had no history of trauma. But they had some points in common, which were they were bilateral cases and their BMI were not low. The incident rate of fatigue fractures of femur with this short stem THAs was 0.3% in our cases. We suggested that one of the causes of these fatigue fractures was the shortness of the stems. The shortness of the stems concentrate the body weight to limited contact area of the femur, and the stress causes the fatigue fractures. We should consider the risk of fatigue fractures on the patients who are operated on bilaterally. However these two patients showed good callus formations and no stem subsidence after a few weeks of partial weight bearing

Gunshot-induced fractures of the proximal femur typically present with severe comminution and bone loss. These fractures may also be associated with local damage to soft tissue, neurovascular structures and injuries to abdominal organs. The aim was to evaluate the outcomes of civilian gunshot injuries to the proximal femur at a major trauma center in South Africa. A retrospective review of all patients who sustained gunshot-induced proximal femur fractures between January 2014 and December 2017 was performed. Patients with gunshot injuries involving the hip joint, neck of femur or pertrochanteric fractures were included. Patient demographics, clinical- treatment and outcome data were collected. Results are reported as appropriate given the distribution of continuous data or as frequencies and counts. Our study included 78 patients who sustained 79 gunshot-induced proximal femur fractures. The mean age of patients was 31 ± 112, and the majority of patients were male (93.6%). Pertrochantenteric fractures were the most common injuries encountered (73.4%). Treatment included cephalomedullary nail (60.8%), arthrotomy and internal fixation (16.4%) and interfragmentary fixation with cannulated screws (6%). One case of complete neck of femur fracture had fixation failure, which required conversion to total hip arthroplasty. The overall union rate was 69.6%, and 6.3% of patients developed a fracture-related infection in cases who completed follow-up. The study shows an acceptable union rate when managing these fractures and a low risk of infection. As challenging as they are, individual approaches for each fracture and managing each fracture according to their merits yield acceptable outcomes

The femur is a common site for skeletal metastases. The Gamma2 nail has proved effective in relieving pain and restoring function. Little data exists on the use of the Gamma3 Long Nail (GLN) in this condition. Improved instrumentation is suggested to reduce operative time and facilitate minimally invasive surgery. This study reports a series of patients treated in a District General Hospital.

A retrospective casenote review was performed of all patients treated with the GLN for femoral metastatic disease over a five year period. Patients were followed-up for a minimum of one year. Functional level was assessed using the Parker Mobility Score (PMS).

12 patients underwent 15 nailings. Mean age was 75.4 years (median 75.7, range 61-92). In bilateral cases, the operations were performed during the same hospital admission. There were seven prophylactic nailings for impending fracture from proximal femoral lesions, seven procedures for actual fractures distal to the intertrochanteric line, and one basicervical fracture associated with multiple femoral metastases. Primaries were four prostate, two breast, two lung, one bowel, one bladder, one renal, and one myeloma.

Average anaesthetic time for all procedures was 134 mins (median 125, range 90-210). Average peri-operative drop in serum haemoglobin was 2.3g/dL (median 2.1, range 0.6-4.8). Five patients with actual fracture and one patient with impending fracture required blood transfusion, receiving 2.2 units on average.

In-hospital mortality rate was 0.83%, with only one patient not surviving to discharge. One year mortality was 83.3%. Only two patients were alive one year post-operation. Of the remaining patients, average survival was 3.2 months (median 3, range 1-6). Patients spent an average of 17 days on an acute orthopaedic unit (median 14, range 4-80). Two patients required further convalescence in a rehabilitation unit.

There were three surgical complications. Two impending fractures became complete, One intra-operatively and one post-operatively. In the case of basi-cervical fracture, the proximal screw cut out of the femoral head, requiring revision to a long-stem bipolar hemiarthroplasty. This was the only re-operation required in this series.

Average pre-operative PMS was 5.2 (median 4, range 2-9). Average peri-operative drop in PMS was two points (median 1.5, range 0-6). Of the 11 patients who survived to discharge, 10 were independently mobile and returned to their pre-operation residence. Nine required a change in walking aids. Only one patient reported post-operative pain.

This small patient series suggests that the Gamma3 Long Nail is a suitable treatment option for impending and actual metastatic femoral fractures in the District General setting. Length of stay, in-hospital mortality and re-operation rates compare favourably with published data on the Gamma2. There was a significant drop in Parker Mobility Score but all patients bar one were independently mobile and returned to their home. Anaesthetic time was not lower than with the Gamma2, suggesting little tangible benefit of the new instrumentation.

Management of periprosthetic femoral fractures above a Total Knee Arthroplasty remains a challenge. The different treatment options available include casting for undisplaced fractures, ORIF for a displaced fracture with a well-fixed implant or revision arthroplasty for a very distal fracture and for a fracture with a loose implant.

We describe our experience in treating a very distal displaced supracondylar fracture above a well-fixed femoral component in a 68-year-old woman who was recently diagnosed with breast carcinoma and awaiting mastectomy. There was no evidence of metastatic disease. The knee replacement was done 4 years before and the patient did not have any symptoms in the knee prior to the fall. Conventional ORIF with IM nailing or plate osteosynthesis was not possible due to the very distal site of the fracture.

We used a custom modified 95 degree angled blade plate in which a slot was cut in the middle of the blade halfway along its length to accommodate the pegs of the femoral component in the distal fragment. The fracture was reduced and fixed with the angled blade plate restoring length, alignment, and providing coronal stability. The patient had a satisfactory union at 3 months without deformity giving a good range of pain free movement in the knee.

DCS and 95 degree angled blade plate have been used in the past with mixed results. The lag screw or the blade has to be inserted more proximally to avoid the femoral component and so the distal fixation is often sub optimal. In our case modification of the blade allowed more distal placement providing optimal fixation and avoiding complex revision surgery.

Abstract. Introduction. We aimed to compare the outcomes of elderly patients with periarticular distal femur or supracondylar periprosthetic fractures treated with either open reduction internal fixation or distal femoral replacement. Methods. A retrospective review of patients over 65 years with AO Type B and C fractures of the distal femur or Su type I and II periprosthetic fractures treated with either a DFR or ORIF was undertaken. Outcomes including Length of Stay, PROMs (Oxford Knee Score and EQ 5D), infection, union, mortality, complication and reoperation rates were assessed. Data on confounding variables were also collected for multivariate analysis. Patients below 65 years and extra articular fractures were excluded. Results. 23 patients (11 in DFR group and 12 in ORIF group) fulfilled inclusion criteria and were included in the analysis. There was no difference between the DFR and ORIF groups with respect to SDI, demographic variables, ASA grade, FCI, preoperative Hb and renal function. There was no difference in 30 day mortality, reoperation rates, 30 day readmission rates and LOS between the two groups. Mean follow up was 12.7 and 15.9 months respectively in the DFR and ORIF groups. At final follow up after accounting for all confounding variables on multivariate analysis, functional outcomes using OKS (adjusted mean: 29.5 vs 15.8) and Health related Quality of Life outcomes using EQ 5D (adjusted mean: 0.453 vs −0.07) were significantly better in the DFR group. Conclusion. DFR for periarticular and periprosthetic distal femoral fractures in the elderly are associated with better patient reported outcomes

Waiting time to access medical care in Canada is 20% more than the international average. Delay in instituting care in trauma patients has been shown to correlate with higher complication rates and an increase in mortality. About 11% of all fractures occur in the femur and are usually treated operatively. Delay to operative treatment is a source of distress to patients and a major factor for poor outcome. Knowledge gaps exist for statistics on operative delay to fixation of femur fractures and the influence on complications and cost of treatment. This study describes (1) the effect of delay to fixation of femur fractures on complications and on the overall cost of care in hospitals in Quebec Province of Canada; and (2) proposes a time frame within which femur fractures should be operated on to minimize the risk of complications and reduce treatment cost. 6,520 adult patients operated for closed femoral fractures between July 1993 and December 2002 were reviewed. Data was accessed from (a) the Quebec Trauma Registry, (b) the hospitalised patients’ database, Maintenance et exploitation des données pour l’étude de la clientèle hospitalière (MED-ECHO) and (c) the medical insurance claims databases, Régie de l’assurance maladie Québec (RAMQ). Excluded were poly-trauma, open fractures, pathological fractures and delayed diagnoses beyond a week. Data was analysed using the SPSS software version 17.0. Cost analysis was carried out using parametric techniques (Student’s t-test and the generalized longitudinal model). Mean operative delay for femoral fractures was 26.3 hours. Delay was associated with increased complications, ICU stay, length of stay (LOS), hospitalization costs and out-patient follow-up treatment costs. There was a progressive increase in these adverse events which was quite significant after the first 48 hours. ISS >15 predisposed to prolonged ICU stay, LOS and increased cost of treatment. All femur fractures appeared to have a predilection for over-65-year-olds and women. The major cost drivers of operative femur fracture treatment were ISS>15, operative delay ≥48 hours, occurrence of complications, and re-operations. Minimizing operative delay in femur fractures will not only mitigate patient suffering, but also reduce treatment and follow-up costs

This edition of Cochrane Corner looks at some of the work published by the Cochrane Collaboration, covering interventions for treating distal femur fractures in adults; ultrasound and shockwave therapy for acute fractures in adults; and local corticosteroid injection versus placebo for carpal tunnel syndrome.

Aims

Early large treatment effects can arise in small studies, which lessen as more data accumulate. This study aimed to retrospectively examine whether early treatment effects occurred for two multicentre orthopaedic randomized controlled trials (RCTs) and explore biases related to this.

We examined the rates of infection and colonisation by methicillin-resistant Staphylococcus aureus (MRSA) between January 2003 and May 2004 in order to assess the impact of the introduction of an MRSA policy in October 2003, which required all admissions to be screened. Emergency admissions were treated prophylactically and elective beds ring-fenced. A total of 5594 admissions were cross-referenced with 22 810 microbiology results. The morbidity, mortality and cost of managing MRSA-carrying patients, with a proximal fracture of the femur were compared, in relation to age, gender, American Society of Anaesthesiologists grade and residential status, with a group of matched controls who were MRSA-negative. In 2004, we screened 1795 of 1796 elective admissions and MRSA was found in 23 (1.3%). We also screened 1122 of 1447 trauma admissions and 43 (3.8%) were carrying MRSA. All ten ward transfers were screened and four (40%) were carriers (all p < 0.001). The incidence of MRSA in trauma patients increased by 2.6% per week of inpatient stay (r = 0.97, p < 0.001). MRSA developed in 2.9% of trauma and 0.2% of elective patients during that admission (p < 0.001). The implementation of the MRSA policy reduced the incidence of MRSA infection by 56% in trauma patients (1.57% in 2003 (17 of 1084) to 0.69% in 2004 (10 of 1447), p = 0.035). Infection with MRSA in elective patients was reduced by 70% (0.56% in 2003 (7 of 1257) to 0.17% in 2004 (3 of 1806), p = 0.06). The cost of preventing one MRSA infection was £3200. Although colonisation by MRSA did not affect the mortality rate, infection by MRSA more than doubled it. Patients with proximal fractures of the femur infected with MRSA remained in hospital for 50 extra days, had 19 more days of vancomycin treatment and 26 more days of vacuum-assisted closure therapy than the matched controls. These additional costs equated to £13 972 per patient. From this experience we have been able to describe the epidemiology of MRSA, assess the impact of infection-control measures on MRSA infection rates and determine the morbidity, mortality and economic cost of MRSA carriage on trauma and elective orthopaedic wards

With the advancement of the virtual technologies, three-dimensional surgical simulators are now possible. In this article, we describe an immersive simulation platform, allowing students in orthopaedic surgery to learn how to deal with a sample diaphyseal fracture of the femur using LC-DCP plate hole, cortical screw and verbrugge forceps. To reach certain realism, weight of the objects and force feedback are used in addition to the visual scene and the 3D sound. The students feel the weight, the strength of the bone when they pierce the holes, and the vibration of the drill. The simulation is implemented by using CAVE, the CyberGlove, CyberGrasp, and 3D sound system

Distal femoral physeal fractures can cause of growth distrurbance which frequently requires further surgical intervention. The aim of this study was to determine if tibial tuberosity ossification at the time of injury can predict further surgery in patients who have sustained a physeal fracture of the distal femur. We retrospectively investigated all patients who had operative treatment for a distal femoral physeal fracture at a paediatric level one trauma center over a 17 year period. Logistic regression analysis was performed investigating associations between the need for further surgery to treat growth disturbance and tibial tuberosity ossification, age, Salter Harris grade, mode of fixation or mechanism of injury. 74 patients met the inclusion criteria. There were 57 boys (77%) and 17 girls (23%). The average age at time of injury was 13.1 years (range 2.-17.1 years). Following fixation, 30 patients (41%) underwent further surgery to treat growth disturbance. Absence of tibial tuberosity fusion to the metaphysis was significantly associated with need for further surgery (p = < 0 .001). Odds of requiring secondary surgery after tibial tuberosity fusion to metaphysis posteriorly (compared with not fused) were 0.12, 95% CI (0.04, 0.34). The estimate of effect of tibial tuberosity ossification on reoperation rates did not vary when adjusted for gender, mechanism, fixation and Salter Harris grade. When accounting for age, the odds of further operation if the tibial tuberosity is fused to the metaphysis posteriorly (compared with not fused) were 0.28, 95% CI (0.08, 0.94). Tibial tuberosity ossification stage at time of injury is a predictor of further surgery to treat growth disturbance in paediatric distal femoral fractures. Children with distal femoral physeal fractures whose tibial tuberosity was not fused to the metaphysis posteriorly were 8.3 times more likely to require further surgery

Delayed management of high energy femoral shaft fractures is associated with increased complication rates. It has been suggested that there is less urgency to stabilize lower energy femoral shaft fractures. The purpose of this study was to evaluate the effect of surgical delay on 30-day complications following fixation of lower energy femoral shaft fractures. Patients ≥ 18 years who underwent either plate or nail fixation of low energy (falls from standing or up to three steps' height) femoral shaft fractures from 2005 – 2016 were identified from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) via procedural codes. Patients with pathologic fractures, fractures of the distal femur or femoral neck were excluded. Patients were categorized into early (< 2 4 hours) or delayed surgery (2–30 days) groups. Bivariate analyses were used to compare demographics and unadjusted rates of complications between groups. A multivariable logistic regression was used to compare the rate of major and minor complications between groups, while adjusting for relevant covariables. Head injury patients and polytrauma patients are not included in the NSQIP database. Of 2,716 lower energy femoral shaft fracture patients identified, 2,412 (89%) were treated within 1 day of hospital admission, while 304 (11.2%) were treated between 2 and 30 days post hospital admission. Patient age, American Society of Anesthesiologists (ASA) classification score, presence of diabetes, functional status, smoking status, and surgery type (nail vs. plate) were significantly different between groups (p After adjusting for all relevant covariables, delayed surgery significantly increased the odds of 30-day minor complications (p=0.02, OR = 1.48 95%CI 1.01–2.16), and 30-day mortality (p < 0 .001), OR = 1.31 (95%CI 1.03–2.14). The delay of surgical fixation of femoral shaft fractures appears to significantly increase patients' risk of minor adverse events as well as increase mortality. With only 89% of patients being treated in the 24 hour timeframe that constitutes best practice for treatment of femoral shaft fractures, there remains room for improvement. These results suggest that early treatment of all femoral shaft fractures, even those with a lower energy mechanism of injury, leads to improved outcomes

The ideal operative treatment of displaced sub capital femoral fractures in the elderly is controversial. Recently, randomised controlled trials have suggested a better outcome with the use of total hip arthroplasty (THA) to treat displaced intra capsular fractures of the femur for elderly patients in good health. More recently the concept of dual mobility cups is being promoted to avoid dislocations in this cohort of patients. However, overall there is limited evidence to support the choice between different types of arthroplasty. Dislocation remains a main concern with THA, especially when a posterior approach is used. We analysed the outcome of 115 primary THR (112 cements and 3 uncemented) THR using a posterior approach with soft tissue repair in active elderly patients presenting with displaced intra capsular femoral neck fractures. Size 28 mm head was used in 108 and a size 32 mm head in the rest. All surgery was performed by specialist hip surgeons. Satisfactory results were noted in terms of pain control, return to pre-morbid activity and radiological evidence of bone implant osteo-integration. The 30-day mortality was nil. There were two dislocations and only one needed revision surgery due to recurrent dislocation. In conclusion, with optimal patient selection, THA seems to provide a good functional outcome and pain relief in the management of displaced intracapsular femoral neck fractures. Excellent outcome can be achieved when done well using the standard cemented THR and with 28mm head. A good soft tissue repair and a specialist hip surgeon is preferable

Periprosthetic fractures around the femur during and after total hip arthroplasty (THA) remain a common mode of failure. It is important therefore to recognise those factors that place patients at increased risk for development of this complication. Prevention of this complication, always trumps treatment. Risk factors can be stratified into: 1. Patient related factors; 2. Host bone and anatomical considerations; 3. Procedural related factors; and 4. Implant related factors. Patient Factors. There are several patient related factors that place patients at risk for development of a periprosthetic fracture during and after total hip arthroplasty. Metabolic bone disease, particularly osteoporosis increases the risk of periprosthetic fracture. In addition, patients that smoke, have long term steroid use or disuse, osteopenia due to inactivity should be identified. A metabolic bone work up and evaluation of bone mineralization with a bone densitometry test can be helpful in identifying and implementing treatment prior to THA. Pre-operative Host Bone and Anatomic Considerations. In addition to metabolic bone disease the “shape of the bone” should be taken into consideration as well. Dorr has described three different types of bone morphology (Dorr A, B, C), each with unique characteristics of size and shape. It is important to recognise that not one single cementless implant may fit all bone types. The importance of templating a THA prior to surgery cannot be overstated. Stem morphology must be appropriately matched to patient anatomy. Today, several types of cementless stem designs exist with differing shape and areas of fixation. It is important to understand via pre-operative templating which stem works best in what situation. Procedural Related Factors. There has been a resurgence in interest in the varying surgical approaches to THA. While the validity and benefits of each surgical approach remains a point of debate, each approach carries with it its own set of risks. Several studies have demonstrated increased risk of periprosthetic fractures during THA with the use of the direct anterior approach. Risk factors for increased risk of periprosthetic fracture may include obesity, bone quality and stem design. Implant Related Factors. As mentioned there are several varying cementless implant shapes and sizes that can be utilised. There is no question that cementless fixation remains the most common mode of fixation in THA. However, one must not forget the role of cemented fixation in THA. Published results on long term fixation with cemented stems are comparable if not exceeding those of press fit fixation. In addition, the literature is clear that cemented fixation in the elderly hip fracture patient population is associated with a lower risk of periprosthetic fracture and lower risk of revision. The indication and principles of cemented stem fixation in THA should not be forgotten

Advances in cancer therapy have prolonged patient survival even in the presence of disseminated disease and an increasing number of cancer patients are living with metastatic bone disease (MBD). The proximal femur is the most common long bone involved in MBD and pathologic fractures of the femur are associated with significant morbidity, mortality and loss of quality of life (QoL). Successful prophylactic surgery for an impending fracture of the proximal femur has been shown in multiple cohort studies to result in longer survival, preserved mobility, lower transfusion rates and shorter post-operative hospital stays. However, there is currently no optimal method to predict a pathologic fracture. The most well-known tool is Mirel's criteria, established in 1989 and is limited from guiding clinical practice due to poor specificity and sensitivity. The ideal clinical decision support tool will be of the highest sensitivity and specificity, non-invasive, generalizable to all patients, and not a burden on hospital resources or the patient's time. Our research uses novel machine learning techniques to develop a model to fill this considerable gap in the treatment pathway of MBD of the femur. The goal of our study is to train a convolutional neural network (CNN) to predict fracture risk when metastatic bone disease is present in the proximal femur. Our fracture risk prediction tool was developed by analysis of prospectively collected data of consecutive MBD patients presenting from 2009–2016. Patients with primary bone tumors, pathologic fractures at initial presentation, and hematologic malignancies were excluded. A total of 546 patients comprising 114 pathologic fractures were included. Every patient had at least one Anterior-Posterior X-ray and clinical data including patient demographics, Mirel's criteria, tumor biology, all previous radiation and chemotherapy received, multiple pain and function scores, medications and time to fracture or time to death. We have trained a convolutional neural network (CNN) with AP X-ray images of 546 patients with metastatic bone disease of the proximal femur. The digital X-ray data is converted into a matrix representing the color information at each pixel. Our CNN contains five convolutional layers, a fully connected layers of 512 units and a final output layer. As the information passes through successive levels of the network, higher level features are abstracted from the data. The model converges on two fully connected deep neural network layers that output the risk of fracture. This prediction is compared to the true outcome, and any errors are back-propagated through the network to accordingly adjust the weights between connections, until overall prediction accuracy is optimized. Methods to improve learning included using stochastic gradient descent with a learning rate of 0.01 and a momentum rate of 0.9. We used average classification accuracy and the average F1 score across five test sets to measure model performance. We compute F1 = 2 x (precision x recall)/(precision + recall). F1 is a measure of a model's accuracy in binary classification, in our case, whether a lesion would result in pathologic fracture or not. Our model achieved 88.2% accuracy in predicting fracture risk across five-fold cross validation testing. The F1 statistic is 0.87. This is the first reported application of convolutional neural networks, a machine learning algorithm, to this important Orthopaedic problem. Our neural network model was able to achieve reasonable accuracy in classifying fracture risk of metastatic proximal femur lesions from analysis of X-rays and clinical information. Our future work will aim to externally validate this algorithm on an international cohort

Age-related fragility fractures are highly correlated with the loss of bone integrity and deteriorated morphology of the osteocytes. Previous studies have reported low-magnitude high-frequency vibration(LMHFV) promotes osteoporotic diaphyseal fracture healing to a greater extent than in age-matched normal fracture healing, yet how osteoporotic fractured bone responds to the mechanical signal has not been explored. As osteocytes are prominent for mechanosensing and initiating bone repair, we hypothesized that LMHFV could enhance fracture healing in ovariectomized metaphyseal fracture through morphological changes and mineralisation in the osteocyte Lacuno-canalicular Network(LCN). As most osteoporotic fractures occur primarily at the metaphysis, an osteoporotic metaphyseal fracture model was established. A total of 72 six-month old female Sprague-Dawley rats (n=72) were obtained(animal ethical approval ref: 16–037-MIS). Half of the rats underwent bilateral ovariectomy(OVX) and kept for 3 months for osteoporosis induction. Metaphyseal fracture on left distal femur was created by osteotomy and fixed by a plate. Rats were then randomized to (1) OVX+LMHFV(20 mins/day and 5 days/week, 35Hz, 0.3g), (2) OVX control, (3) SHAM+LMHFV, (4) SHAM control. Assessments of morphological structural changes, functional markers of the LCN(Scanning Electron Microscopy, FITC-Imaris, immunohistochemistry), mineralization status(EDX, dynamic histomorphometry) and healing outcomes(X-ray, microCT, mechanical testing) were performed at week 1, 2 and 6 post-fracture. One‐way ANOVA with post-hoc test was performed. Statistical significance was set at p < 0.05. Our results showed LMHFV could significantly enhance the morphology of the LCN. There was a 65.3% increase in dendritic branch points(p=0.03) and 93% increase in canalicular length(p=0.019) in the OVX-LMHFV group at week 2 post-fracture. Besides, a similar trend was also observed in the SHAM+LMHFV group, with a 43.4% increase in branch points and 53% increase in canaliculi length at week 2. A significant increase of E11 and DMP1 was observed in the LMHFV groups, indicating the reconstruction of the LCN. The decreasing sclerostin and increasing FGF23 at week 1 represented the active bone formation phase while the gradual increase at week 6 signified the remodelling phase. Furthermore, Ca/P ratio, mineral apposition rate and bone formation rate were all significantly enhanced in the OVX+LMHFV group. The overall bone mineral density in BV was significantly raised in the OVX+LMHFV group at week 2(p=0.043) and SHAM+LMHFV at week 6(p=0.04). Quantitative analysis of microCT showed BV/TV was significantly increased at week 2 in OVX+LMHFV group(p=0.008) and week 6(p=0.001) in both vibration groups. In addition, biomechanical testing revealed that the OVX+LMHFV group had a significantly higher ultimate load(p=0.03) and stiffness(p=0.02) at week 2. To our best knowledge, this is the first report to illustrate LMHFV could enhance osteocytes' morphology, mineralisation status and healing outcome in a new osteoporotic metaphyseal fracture animal model. Our cumulative data supports that the mechanosensitivity of bone would not impair due to osteoporosis. The revitalized osteocyte LCN and upregulated osteocytic protein markers implied a better connectivity and transduction of signals between osteocytes, which may foster the osteoporotic fracture healing process through an enhanced mineralisation process. This could stimulate further mechanistic investigations with potential translation of LMHFV to our fragility fracture patients

Intra-operative fractures of the femur are on the rise mainly due to the increased use of cementless implants and the desire to get a tight press fit. The prevalence has been reported to be between 1–5% in cementless THAs. The key to preventing these fractures is to identify patients at high risk and careful surgical technique. Surgical risk factors include the use of cementless devices, revision hip surgery, the use of flat tapered wedges and MIS surgery. Patient factors that increased risk include increasing age, female gender, osteopenia and rheumatoid arthritis. These risk factors tend to be additive and certainly when more than one is present extra caution needs to be taken. Surgical technique is critical to avoid these intra-operative fractures. Fractures can occur during exposure and dislocation, during implant removal (in revision THA), during canal preparation and most commonly during stem insertion. In both primary, and especially in revision, THA be wary of the stiff hip in association with osteopenia or osteolysis. These patients require a very gentle dislocation. If this cannot be achieved, then alteration of the standard approach and dislocation may be needed. Examples of these include protrusion with an osteopenic femur and revision THA with a very stiff hip with lysis in the femur. Lastly, in cases with retained hardware, dislocate prior to removing plates and screws. After dislocation, the next challenge is gentle preparation of the femoral canal. A reasonable exposure is required to access the femoral canal safely. MIS procedures do not offer good access to femoral canal and this probably results in increased risk of fracture during broaching or implant insertion. When broaching, stop when broach will not advance further. When inserting a tapered wedge stem, be worried if stem goes further in than broach. In revision surgery, when taking the stem out from above, make sure the area of the greater trochanter does not overhang the canal. A high speed burr can clear the shoulder for easier access for removal. In revision THA with an ETO, place a cerclage wire prior to reaming and retighten prior to stem insertion. Even with careful surgical technique intra-operative femoral fractures will still occur. When inserting the stem, a sudden change in resistance is highly suggestive of fracture. Wide exposure of the entire proximal femur is necessary to confirm the diagnosis. The distal extent of the fracture must be seen. Only on occasion is an intra-operative radiograph needed. Management is directed to ensuring component stability and good fracture fixation. In primary total hip arthroplasty, calcar fractures are by far the most common. If using proximal fixation and you are certain the stem is stable, then all that is needed is cerclage wiring. As already mentioned, you must follow the fracture line distally so you are aware of how far down it goes. Often what appears to be a calcar split actually propagates distal to the lesser trochanter. In these cases, one would probably go for distal fixation plus wiring. In conclusion, intra-operative femoral fractures are on the rise. Prevention is the key

Advances in cancer therapy have prolonged cancer patient survival even in the presence of disseminated disease and an increasing number of cancer patients are living with metastatic bone disease (MBD). The proximal femur is the most common long bone involved in MBD and pathologic fractures of the femur are associated with significant morbidity, mortality and loss of quality of life (QoL). Successful prophylactic surgery for an impending fracture of the proximal femur has been shown in multiple cohort studies to result in patients more likely to walk after surgery, longer survival, lower transfusion rates and shorter post-operative hospital stays. However, there is currently no optimal method to predict a pathologic fracture. The most well-known tool is Mirel's criteria, established in 1989 and is limited from guiding clinical practice due to poor specificity and sensitivity. The goal of our study is to train a convolutional neural network (CNN) to predict fracture risk when metastatic bone disease is present in the proximal femur. Our fracture risk prediction tool was developed by analysis of prospectively collected data for MBD patients (2009–2016) in order to determine which features are most commonly associated with fracture. Patients with primary bone tumors, pathologic fractures at initial presentation, and hematologic malignancies were excluded. A total of 1146 patients comprising 224 pathologic fractures were included. Every patient had at least one Anterior-Posterior X-ray. The clinical data includes patient demographics, tumor biology, all previous radiation and chemotherapy received, multiple pain and function scores, medications and time to fracture or time to death. Each of Mirel's criteria has been further subdivided and recorded for each lesion. We have trained a convolutional neural network (CNN) with X-ray images of 1146 patients with metastatic bone disease of the proximal femur. The digital X-ray data is converted into a matrix representing the color information at each pixel. Our CNN contains five convolutional layers, a fully connected layers of 512 units and a final output layer. As the information passes through successive levels of the network, higher level features are abstracted from the data. This model converges on two fully connected deep neural network layers that output the fracture risk. This prediction is compared to the true outcome, and any errors are back-propagated through the network to accordingly adjust the weights between connections. Methods to improve learning included using stochastic gradient descent with a learning rate of 0.01 and a momentum rate of 0.9. We used average classification accuracy and the average F1 score across test sets to measure model performance. We compute F1 = 2 x (precision x recall)/(precision + recall). F1 is a measure of a test's accuracy in binary classification, in our case, whether a lesion would result in pathologic fracture or not. Five-fold cross validation testing of our fully trained model revealed accurate classification for 88.2% of patients with metastatic bone disease of the proximal femur. The F1 statistic is 0.87. This represents a 24% error reduction from using Mirel's criteria alone to classify the risk of fracture in this cohort. This is the first reported application of convolutional neural networks, a machine learning algorithm, to an important Orthopaedic problem. Our neural network model was able to achieve impressive accuracy in classifying fracture risk of metastatic proximal femur lesions from analysis of X-rays and clinical information. Our future work will aim to validate this algorithm on an external cohort

Aims

Orthopaedic surgeries are complex, frequently performed procedures associated with significant haemorrhage and perioperative blood transfusion. Given refinements in surgical techniques and changes to transfusion practices, we aim to describe contemporary transfusion practices in orthopaedic surgery in order to inform perioperative planning and blood banking requirements.