Abstract. Background. Dislocation of a hip hemiarthroplasty is a devastating complication with a high mortality rate in elderly patients. Previous studies have suggested a higher dislocation rate in patients with neuromuscular conditions. In this study, we have reviewed our larger cohort of patients to identify whether there is any association between neuromuscular disorders and prosthetic dislocation in patients treated with hip hemiarthroplasty for femoral neck fractures. Patients and Methods. Our study is a retrospective analysis of data collected over 34 years for patients with intracapsular neck of femur fracture who underwent hip hemiarthroplasty. The study population is composed of four groups: patients with no neuromuscular disorders, patients with Parkinson's disease, patients with previous stroke, and patients with dementia. Results. A total of 3827 patients were treated with hip hemiarthroplasty. For the 3371 patients with no neuromuscular condition (Group I) the dislocation rate was 1.1%. 219 patients had Parkinsonism (Group II) with a dislocation rate of 3.2%, 104 patients had a previous stroke with weakness on the fracture side with a dislocation rate of 1.0% (Group III), and 984 patients had severe dementia with a dislocation rate of 1.8% (Group IV). The increased dislocation rate for those with Parkinson's disease was statistically significant (p=0.02) while none of the other neuromuscular conditions were statistically significant. Conclusion. Our study demonstrates an increased risk of dislocation after hemiarthroplasty for patients with Parkinson's disease in comparison to other groups. No increase was apparent for those with dementia or weakness from a previous stroke

Introduction and Objective. Dislocation of a hip hemiarthroplasty is a significant complication with a high mortality rate in elderly patients. Previous studies have shown a higher risk of dislocation in patients with neuromuscular conditions. In this study, we reviewed our larger cohort of patients to identify if there is a link between neuromuscular disorders and dislocation of hip hemiarthroplasty in patients with neuromuscular conditions. Materials and Methods. We have retrospectively analysed a single-centre data that was collected over 34 years for patients with intracapsular neck of femur fracture who underwent hip hemiarthroplasty. The study population was composed of four groups: patients with no neuromuscular disorders, patients with Parkinson's disease, patients with previous stroke, and patients with mental impairment. Results. A total of 3827 patients were included in the analysis. 3371 patients had no neuromuscular condition (Group I) with a dislocation rate of 1.1%. 219 patients had Parkinsonism (Group II) with a dislocation rate of 3.2%, 104 patients had a previous stroke with weakness on the fracture side with a dislocation rate of 1.0% (Group III), and 984 patients had severe mental impairment with a dislocation rate of 1.8% (Group IV). The increased dislocation rate for those with Parkinson's disease was statistically significant (p=0.02) while none of the other neuromuscular conditions were statistically significant. Conclusions. Our study has shown an increased risk of dislocation of hemiarthroplasty in patients with Parkinson's disease in comparison to other groups. No increase was apparent for patients with mental impairment or weakness from a previous stroke

Revision knee arthroplasty is a complex procedure with the number and cost of knee revision procedures performed per year expected to rise. Few studies have examined adverse events following revision arthroplasty. The objective of this study was to determine rates of serious adverse events in patients undergoing revision knee arthroplasty with consideration of the indication for revision (urgent versus elective indications) and to compare these with primary arthroplasty and re-revision arthroplasty. Patients undergoing primary knee arthroplasty were identified in the UK Hospital Episode Statistics. Subsequent revision and re-revision arthroplasty procedures in the same patients and same knee were identified. The primary outcome was 90-day mortality and a logistic regression model was used to investigate factors associated with 90-day mortality and secondary adverse outcomes including infection (undergoing surgery), pulmonary embolism, myocardial infarction, stroke. Urgent indications for revision arthroplasty were defined as infection or fracture, and all other indications were included in the elective indications cohort. 939,021 primary knee arthroplasty cases were included of which 40,854 underwent subsequent revision arthroplasty, and 9,100 underwent re-revision arthroplasty. Revision surgery for elective indications was associated with a 90-day rate of mortality of 0.44% (135/30,826; 95% CI 0.37-0.52) which was comparable to primary knee arthroplasty (0.46%; 4,292/939,021; 95% CI 0.44-0.47). Revision arthroplasty for infection, however, was associated with a much higher mortality of 2.04% (184/9037; 95% CI 1.75-2.35; odds ratio [OR] 3.54; 95% CI 2.81-4.46), as was revision for periprosthetic fracture at 5.25% (52/991; 95% CI 3.94-6.82; OR 6.23; 95% CI 4.39-8.85). Higher rates of pulmonary embolism, myocardial infarction, and stroke were also observed in the infection and fracture cohort. These findings highlight the burden of complications associated with revision knee arthroplasty. They will inform shared decision-making for patients considering revision knee arthroplasty for elective indications. Patients presenting with infection of a knee arthroplasty or a periprosthetic fracture are at very high risk of adverse events. It is important that acute hospital services and tertiary referral centres caring for these patients are appropriately supported to ensure appropriate urgency and an anticipation for increased care requirements

Cerebral Palsy (CP) is a group of disorders that affect movement and posture caused by injury to the developing brain. While prematurity and low birth weight are common causes in developed countries, birth asphyxia, kernicterus, and infections have been identified as predominant aetiologies in Africa. There is, however, very little information on the aetiology of CP in South Africa. The purpose of this study was to determine the aetiology, severity, and topographical distribution of CP in children undergoing orthopaedic surgery at our tertiary paediatric unit. A retrospective folder review was performed for patients with CP that underwent orthopaedic surgery from July 2018 to June 2022. Data was collected on perinatal circumstances, aetiology or risk factors for developing CP, severity of disability as classified by the Gross Motor Function Classification Scale (GMFCS) and topographical distribution. Descriptive analysis was performed. Two-hundred-and-thirty-four patients were included in the analysis. No specific aetiology could be identified in 51 (21.9%) patients. Hypoxic ischaemic encephalopathy (HIE) accounted for 23.6% of patients and was the most common aetiology across the different categories except for patients graded as GMFCS 2, in whom prematurity was the most common aetiology. Congenital brain malformations (10.5%) and cerebral infections, including HIV encephalopathy (11.4%) were the next most frequent aetiologies, followed by prematurity (7.6%), ischaemic stroke (6.8%) and intraventricular haemorrhage (6.3%). Fifty-two percent of patients were classified as GMFCS 4 or 5. There was a predominance of quadriplegic patients (37%) compared to hemiplegics (29%), diplegics (30%) and monoplegics (4%). Most patients undergoing orthopaedic surgery for musculoskeletal sequelae of CP were severely disabled quadriplegic patients in whom HIE was the predominant cause of CP. This emphasises the need for intervention at a primary care level to decrease the incidence of this frequently preventable condition

Introduction. VTE is a possible complication of foot and ankle surgery, however there is an absence of agreement on contributing risk factors in the development of VTE. The primary outcome of this study was to analyse the 90-day incidence of symptomatic VTE following foot and ankle surgery and to determine which factors may increase the risk of VTE. Methods. This was a national, multi-centre prospective audit spanning a collection duration of 9 months (2022/2023). Primary outcomes included incidence of symptomatic VTE and VTE related mortality up to 90 days following foot and ankle surgery and Achilles tendon rupture, and analysis of risk factors. Results. In total 11,363 patients were available for analysis. 5,090 patients (44.79%) were elective procedures, 4,791 patients (42.16%) were trauma procedures (excluding Achilles ruptures), 398 patients (3.50%) were acute diabetic procedures, 277 patients (2.44%) were Achilles ruptures undergoing surgery and 807 patients (7.10%) were Achilles ruptures treated non-operatively. There were 99 cases of VTE within 90 days of admission across the whole group (Total incidence = 0.87%), with 3 cases of VTE related mortality (0.03%). On univariate analysis, increased age and ASA grade showedhigher odds of 90-day VTE, as did previous cancer, stroke, history of VTE, and type of foot and ankle procedure / injury (p<0.05). However, on multivariate analysis, the only independent predictors for 90-day VTE were found to be the type of foot and ankle procedure (Achilles tendon rupture = Odd's Ratio 11.62, operative to 14.41, non-operative) and ASA grade (grade III/IV = Odd's Ratio 3.64). Conclusion. The incidence of 90-day post procedure VTE in foot and ankle surgery in this national audit was low. Significant, independent risk factors associated with the development of 90-day symptomatic VTE were Achilles tendon rupture management and high ASA grade

We aimed to use data from a randomized controlled trial (RCT) comparing the sliding hip screw vs. intramedullary nailing (IMN) for trochanteric fractures to examine complication rates between those managed with a short vs. long IMN. This is a secondary analysis using one arm of an RCT of patients ≥18 years with trochanteric fractures. We examined differences in fracture-related (femoral shaft fracture, implant failure, surgical site infection (SSI), nonunion, limb shortening, and pain) and medical (organ failure, respiratory distress, stroke, deep vein thrombosis [DVT] gastrointestinal upset, pneumonia, myocardial infarction, sepsis, or urinary tract infection) adverse events (AE), and readmission between short vs. long IMNs. We included 412 trochanteric fracture patients, 339 (82.2%) of whom received a short (170mm–200mm) nail, while 73 (17.7%) received a long (260mm–460 mm) nail. Patients in the long group were more likely to be admitted from home (vs. an institution), and have comorbidities, or more complex fracture types. Patients in the long group had higher rates of fracture-related AE (12.3%) vs. the short group (3.5%). Specifically, SSI (5.5% vs. 0.3%) and pain (2.7% vs. 0.0%) were significantly higher in the long group. Patients in the long group were also more likely to develop DVT (2.7% vs. 0.3%), and be readmitted to the hospital (28.8% vs. 20.7%). Following covariable adjustment, long nails remained associated with a higher odds of fracture-related AE (5.11, 1.96–13.33) compared to short nails. We found no association between the adjusted odds of readmission and nail length (1.00, 0.52–1.94). Our analyses revealed that trochanteric fracture patients managed with long IMN nails may have a higher odds of fracture-related AE compared to short nails. Future research is required to validate these findings with larger event rates, and further optimize IMN for trochanteric fracture patients

Based on Ilizarov's law of tension-stress principle, distraction histogenesis technique has been widely applied in orthopaedic surgery for decades. Derived from this technique, cranial bone transport technique was mainly used for treating cranial deformities and calvarial defects. Recent studies reported that there are dense short vascular connections between skull marrow and meninges for immune cells trafficking, highlighting complex and tight association between skull and brain. Alzheimer's disease (AD) is a progressive neurodegenerative disease and the most common cause of dementia without effective therapy. Meningeal lymphatics have been recognized as an important mediator in neurological diseases. The augmentation of meningeal lymphatic drainage might be a promising therapeutic target for AD. Our proof-of-concept study has indicated that cranial bone transport can promote ischemic stroke recovery via modulating meningeal lymphatic drainage function, providing a rationale for treating AD using cranial bone maneuver (CBM). This study aims to investigate the effects of CBM on AD and to further explore the potential mechanisms. Transgenic 5xFAD mice model was used in this study. After osteotomy, a bone flap was used to perform CBM without damaging the dura. Open filed test, novel object recognition test and Barn's maze test were used to evaluate neurological functions of 5xFAD mice after CBM treatment. Congo red and immunofluorescence staining were used to evaluate amyloid depositions and Aβ plaques in different brain regions. Lymphangiogenesis and the level of VEGF-C were examined after CBM treatment. OVA-A647 was intra-cisterna-magna injected to evaluate meningeal lymphatic drainage function after CBM treatment. CBM significantly improved memory functions and reduced amyloid depositions and Aβ plaques in the hippocampus of 5xFAD mice. A significant increase of meningeal lymphatic vessels in superior sagittal sinus and transverse sinus, and the upregulation of VEGF-C in meninges were observed in 5xFAD mice treated with CBM. Moreover, CBM remarkably enhanced meningeal lymphatic drainage function in 5xFAD mice (n=5-16 mice/group for all studies). CBM may promote meningeal lymphangiogenesis and lymphatic drainage function through VEGF-C-VEGFR3 pathway, and further reduce amyloid depositions and Aβ plaques and alleviate memory deficits in AD

Aim. Patient quality of life (QoL) in untreated bone infection was compared to other chronic conditions and stratified by disease severity. Method. Patients referred for treatment of osteomyelitis (including fracture related infection) were identified prospectively between 2019 and 2023. Patients with confirmed infection completed the EuroQol EQ-5D-5L questionnaire. Clinicians blinded to EQ-index score, grouped patients according to JS-BACH Classification into ‘Uncomplicated’, ‘Complex’ or ‘Limited treatment options’. A systematic review of the literature was performed of other conditions that have been stratified using EQ-index score. Results. 257 patients were referred, and 219 had suspected osteomyelitis. 196 patients had long bone infection and reported an average EQ-index score of 0.455 (SD 0.343). 23 patients with pelvic osteomyelitis had an average EQ-index score of 0.098 (SD 0.308). Compared to other chronic conditions, patients with long-bone osteomyelitis had worse QoL when compared to different types of malignancy (including bladder, oropharyngeal, colorectal, thyroid and myeloma), cardiorespiratory disease (including asthma, COPD and ischaemic heart disease), psychiatric conditions (including depression, pain and anxiety), endocrine disorders (including diabetes mellitus), neurological conditions (including Parkinson's disease, chronic pain and radiculopathy) and musculoskeletal conditions (including osteogenesis imperfecta, fibrous dysplasia and x-linked hypophosphataemic rickets). QoL in long-bone infection was similar to conditions such as Prada-Willi syndrome, Crohn's disease and juvenile idiopathic arthritis. Patients who had a history of stroke or multiple sclerosis reported worse QoL scores compared to long-bone infection. Patients who had pelvic osteomyelitis gave significantly lower QoL scores when compared to all other conditions that were available for comparison in the literature. In long bone infection, 41 cases (21.0%) were classified as ‘Uncomplicated’, 136 (69.4%) as ‘Complex’ and 19 (9.7%) as ‘Limited treatment options available’. Within classification stratification, patients with ‘Uncomplicated’ long bone infections reported a mean EQ-index score of 0.618 (SD 0.227) which was significantly higher compared to ‘Complex’ (EQ-index: 0.410 SD 0.359, p=0.004) and ‘Limited treatment options available’ (EQ-index: 0.400 SD 0.346, p=0.007). Conclusions. Bone and joint infections have a significant impact on patient quality of life. It is much worse when compared to other common chronic conditions, including malignancy, cardiovascular and neurological diseases. This has not been previously reported but may focus attention on the need for more investment in this patient group

Abstract. Introduction. The objective of this study was to determine rates of serious adverse events in patients undergoing revision knee arthroplasty with consideration of the indication for revision and compare these with primary knee arthroplasty. Methodology. Primary and revision arthroplasty procedures were identified in the national Hospital Episode Statistics and were linked by patient and side. A logistic regression model was used to investigate factors associated with 90-day mortality (primary outcome) and secondary serious adverse outcomes. Urgent indications for revision arthroplasty were defined as infection or fracture; other indications (e.g. loosening, instability, wear) were included in the elective cohort. Results. 939,021 primary knee arthroplasty and 40,584 revision cases were included. Revision surgery for elective indications was associated with a 90-day rate of mortality of 0.44% (95% CI 0.37-0.52) which was comparable to primary knee arthroplasty (0.46%; 95% CI 0.44-0.47). Revision arthroplasty for infection, however, was associated with a much higher mortality of 2.04% (95% CI 1.75-2.35; odds ratio [OR] 3.54; 95% CI 2.81-4.46), as was revision for periprosthetic fracture at 5.25% (95% CI 3.94-6.82; OR 6.23; 95% CI 4.39-8.85). Higher rates of PE, MI, and stroke were observed in the infection and fracture cohort. Conclusion. Patients presenting with infection of a knee arthroplasty or a periprosthetic fracture are at very high risk of adverse events. It is important that acute hospital services and tertiary referral centres caring for these patients are appropriately supported to ensure appropriate urgency with an anticipation for increased care requirements

Low back pain (LBP) is a common problem in rowers of all levels. Few studies have looked at the relationship between rowing technique, the forces generated during the rowing stroke and the kinematics of spinal motion. Of particular concern with respect to spinal injury and damage are the effects of fatigue during long rowing sessions. A technique has been developed using an electromagnetic motion system and strain gauge instrumented load cell to measure spinal and pelvic motion and force generated at the oar during rowing on an exercise rowing ergometer. Using this technique 13 elite national and international oarsmen (mean age 22.43 ± 0.02 years) from local top squad rowing teams were investigated. The test protocol comprised of a one hour rowing piece. During this session rowing stroke profiles were quantified in terms of lumbopelvic kinematics and stroke force profiles. These profiles were sampled at the start of the session and quarterly intervals during the hour piece. From this data we were able to quantify the motion of the lumbar spine and pelvis during rowing and relate this to the stroke force profile. The stroke profiles over the one hour piece were then compared to examine the effects of fatigue. This revealed marked changes and increases in the amount of spinal motion during the hour piece suggesting that to maintain stroke force profiles athletes were utilising greater ranges of spinal motion. The relevance of this with regard to low back pain however, requires further investigation

Aim. To investigate self-reported quality of life (QoL) in patients with osteomyelitis referred to a specialist centre in the UK and investigate the relationship between QoL and BACH classification. Method. All patients newly referred to a specialist bone infection clinic at a single tertiary centre within the UK between January 2019 and February 2020 were prospectively included. Diagnosis of osteomyelitis was made according to the presence of clinical and radiological criteria for ≥6 months. An EQ-5D-5L questionnaire and visual analogue score (VAS) were completed during the initial clinic appointment. Long-bone osteomyelitis was classified by the attending orthopaedic surgeon using the BACH classification system as either uncomplicated, complex or with limited options available.1 Patients managed non-operatively were subclassified into those who were (i) unfit to receive an operation or (ii) fit and well with stable disease. EQ-5D index scores were compared to a published UK value set of 41 chronic health conditions within the UK.2. Results. 201 patients were referred during the study period, with 159 (79.1%) patients diagnosed with long-bone osteomyelitis and 16 (8.0%) with osteomyelitis of the pelvic bones. Patients with pelvic osteomyelitis reported lower EQ-5D index scores compared to long-bone osteomyelitis (EQ-5D: 0.097 vs. 0.435, p<0.001) but similar VAS (60.2 vs. 54.6, p=0.37). Long-bone and pelvic osteomyelitis gave the 40th and 41st lowest EQ-5D scores respectively when compared to 41 other chronic health conditions including stroke, chronic obstructive pulmonary disease, kidney disease, liver disease and malignancy. Patients classified as having uncomplicated long-bone osteomyelitis reported significantly higher QoL compared to those classified as complex osteomyelitis (EQ-5D: 0.527 vs. 0.401, p<0.05; VAS: 66.9 vs. 58.4, p<0.05). Patients who were not fit for surgery due to co-morbidity reported similar QoL scores compared to those patients with complex osteomyelitis (EQ-5D: 0.293, p=0.07; VAS: 46.6, p=0.06). Patients with stable disease who did not require surgery, gave significantly better QoL scores when compared to the other classifications of osteomyelitis (EQ-5D: 0.746, p<0.01; VAS: 81.9, p<0.01). Conclusions. Patient reported QoL in osteomyelitis correlates with disease complexity as classified according to the BACH classification system. Patients with pelvic and long-bone osteomyelitis rate their QoL lower than patients with other chronic diseases

Abstract. Objectives. Our study evaluates financial impact to the Best Practice Tariff (BPT) of hip fracture patients on Novel Oral Anti-Coagulant (NOAC) medication. Since their approval by NICE for the prevention of stroke and systemic embolism in non-valvular atrial fibrillation, the incidence of hip fracture patients admitted to hospitals on NOAC medication (e.g. rivaroxiban, apixaban) has been increasing. BPT for hip fractures has two components: a base tariff and a conditional top-up tariff of £1,335 per patient (applied to patients of 60 years of age). For the top-up tariff, six criteria must be met, of which time-to-surgery within 36 hours is one. Our department currently recommends withholding NOAC medication and delaying surgery for at least 48 hours as per our Trust's haematology guidelines to reduce intra-operative bleeding risk. Therefore, the conditional top-up tariff cannot be claimed for these patients. Method. A retrospective review of our Trust hip fracture patients over 60 years of age admitted during 2019 on NOAC medication using National Hip Fracture Database (NHFD). Results. 545 hip fracture patients had operative treatment at our Trust during the one-year period of 2019. 31 of these patients were admitted on NOAC medication, and therefore had to stop the NOAC and wait for at least 48 hours before having surgery. This translates to a potential hip fracture BPT loss of £41,385 in 2019, as the conditional top-up tariff could not be claimed. Conclusion. This study illustrates the large financial impact to BPT that hip fracture patients admitted on NOAC medications has at our Trust. It raises the argument as to whether the BPT should allow for an increased length of time until surgery for such patients, to allow safe surgical treatment with reduced bleeding risk. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Introduction. This study assesses self-reported quality of life (QoL) in patients with osteomyelitis referred to a specialist centre in the UK. Materials and Methods. All patients newly referred to a specialist tertiary bone infection clinic within the UK between January 2019 and February 2020 were prospectively included. Diagnosis of osteomyelitis was made according to the presence of clinical and radiological criteria for ≥6 months. An EQ-5D-5L questionnaire and visual analogue score (VAS) were completed during the initial clinic appointment. Long-bone osteomyelitis was classified by the attending orthopaedic surgeon using the BACH classification system as either uncomplicated, complex or with limited options available. Patients managed non-operatively were subclassified into those who were (i) unfit to receive an operation or (ii) fit and well with stable disease. EQ-5D index scores were compared to a published UK value-set of 41 chronic health conditions within the UK. Results. 201 new patients were referred during the study period. 159 (79.1%) met the criteria for long-bone osteomyelitis and 16 (8.0%) for osteomyelitis of the pelvic bones. Patients with pelvic osteomyelitis reported lower EQ-5D index scores compared to long-bone osteomyelitis (EQ-5D:0.097 vs. 0.435, p<0.001) but similar VAS (60.2 vs. 54.6, p=0.37). Long-bone and pelvic osteomyelitis gave the lowest EQ-5D scores respectively when compared to 41 other chronic health conditions including stroke, chronic obstructive pulmonary disease, kidney disease, liver disease and malignancy. Patients classified as having uncomplicated long-bone osteomyelitis reported significantly higher QoL compared to those classified as complex osteomyelitis (EQ-5D:0.527 vs. 0.401, p<0.05; VAS: 66.9 vs. 58.4, p<0.05). Patients not fit for surgery due to co-morbidity reported similar QoL scores compared to those patients with complex osteomyelitis (EQ-5D: 0.293, p=0.07; VAS: 46.6, p=0.06). Patients with stable disease who did not require surgery, gave significantly better QoL scores when compared to the other classifications of osteomyelitis (EQ-5D: 0.746, p<0.01; VAS: 81.9, p<0.01). Conclusions. Patient reported QoL in osteomyelitis correlates with disease complexity as classified according to the BACH classification system. Patients with pelvic and long-bone osteomyelitis rate their QoL lower than patients with other major chronic diseases

Background. There is a lack of information on the independent preoperative predictors of perioperative mortality, including the influence of previous stroke and acute coronary syndromes (myocardial infarction + unstable angina, ACS). Previous studies have grouped variables under the umbrella term “ischaemic heart disease”. In this study, we investigated the influence of vascular risk factors separately. Methods. The Hospital Episode Statistics database was analyzed for elective admissions for total hip (THR) and total knee (TKR) replacements between 2004 and 2009. Independent preoperative predictors of perioperative outcome were identified from admission secondary diagnosis codes. Perioperative mortality was defined as 30-day in-hospital death. Logistic regression analysis was used to identify independent predictors of 30-day mortality. Data was adjusted for age, social deprivation and Charlson co-morbidity score. Results. 414,985 THRs and TKRs were performed in the study period. There were 829 deaths within 30 days (0.2%). Previous ACS (OR: 1.73 [1.33 to 2.25]) and stroke (OR: 1.64 [1.02 to 2.65]) predicted 30-day mortality. ACS (OR: 3.81 [1.55 to 9.34]) within six months of THKR surgery was associated with increased odds of perioperative mortality. The effect of ACS persisted up to 12 months (OR: 1.99 [1.02 to 3.88]). Renal failure, liver disease, heart failure, peripheral vascular disease and non-atrial fibrillation arrhythmia also increased the odds of mortality. Discussion. Previous stroke and ACS increase the odds of perioperative mortality, together with several other vascular risk factors. Within 12 months of ACS, risk of mortality is significantly elevated. Elective surgery should be avoided in this period

INTRODUCTION. Preoperative optimization and protocols for joint replacement care pathways have led to decreased length of stay (LOS), decreased narcotic use and are increasingly important in delivering quality, cost savings and shifting appropriate cases to an outpatient setting. The intraoperative use of vasopressors is independently associated with increased length of stay, risk of adverse postoperative events including death and in total hip arthroplasty there is an increased risk for ICU admission. Our aim is to characterize the patient characteristics associated with vasopressor use specifically in total knee arthroplasty (TKA). METHODS. We retrospectively reviewed 748 patients undergoing inpatient primary total knee arthroplasty at a single academic institution by two surgeons from 1/1/17 to 12/21/18. Demographics, comorbidities, perioperative factors and intraoperative medication administration were compared with multivariate regression to identify patients who may require intraoperative vasopressors. RESULTS. Seven hundred-forty eight patients underwent total knee arthroplasty and 439 patients required intraoperative vasopressors while 307 did not require vasopressors. Significant predictors of vasopressor use were male sex (p=0.035), history of prior cerebrovascular event (p=0.041) and older age (p=0.048). NPO time, anesthesia provider level of training, operative time, and intraoperative mean arterial pressure and heart rate were not significant predictors of vasopressor use intra-operatively during total knee arthroplasty. CONCLUSION. In this study, nearly fifty-nine percent of patients undergoing TKA received intraoperative vasopressor support. Male gender, history of stroke and older age were significantly associated with increased intraoperative vasopressor use. Surgical time and case order do not appear to be optimizable factors to minimize the use of vasopressors in TKA. Our results highlight variation in anesthesia practices and an opportunity to standardize vasopressor triggers and identify patients who may require vasopressor support during preoperative optimization and selection of their surgical setting

The December 2014 Research Roundup. 360 . looks at: demineralised bone matrix not as good as we thought?; trunk control following ACL reconstruction; subclinical thyroid dysfunction: not quite subclinical?; establishing musculoskeletal function in mucopolysaccharidosis; starting out: a first year in consultant practice under the spotlight; stroke and elective surgery; sepsis and clots; hip geometry and arthritis incidence; and theatre discipline and infection

Background and purpose: Back injury is a common complaint amongst rowers. With long training hours muscle fatigue is an inevitable consequence which may be a precursor to injury. This study aims to explore the effects of fatigue on iliocostalis lumborum (IL) and superficial multifidus (SM) whilst rowing on a Concept 2C rowing ergometer (C2CRE). Method: Nineteen male athletes from Cardiff University Rowing Club were recruited fulfilling specific inclusion criteria (mean age 22yrs ± 3). Ethical approval was obtained from the institutions ethical committee. With bilateral EMG electrodes (IL and SM) attached Maximum Voluntary Contractions were collected followed by a 10 minute warm up on a C2CRE. Subjects subsequently performed a 7 stroke power test (pre fatigue condition) (. Godfrey and Williams 2007. ). Subjects then rowed at a power rate of an average power rating from the 7 stroke power test. As soon as subjects power ratings fell below 85% of the average they stopped, and then immediately performed the 7 stroke power test whilst EMG data (IL and SM) was collected (post fatigue condition). Paired T tests reported differences between pre and post fatigue scores for IL and SM. Results: A non significant trend in IL between pre and post fatigue conditions (p=0.065) was noted with no significant difference in SM activity (p=0.196). Conclusion: This study has provided evidence that there is a difference in muscle activity between IL and SM following a fatiguing protocol, which may play an important role in the understanding of mechanisms leading to low back pain in rowers

Objectives. We have increased the dose of tranexamic acid (TXA) in our enhanced total joint recovery protocol at our institution from 15 mg/kg to 30 mg/kg (maximum 2.5 g) as a single, intravenous (IV) dose. We report the clinical effect of this dosage change. Methods. We retrospectively compared two cohorts of consecutive patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) surgery in our unit between 2008 and 2013. One group received IV TXA 15 mg/kg, maximum 1.2 g, and the other 30 mg/kg, maximum 2.5 g as a single pre-operative dose. The primary outcome for this study was the requirement for blood transfusion within 30 days of surgery. Secondary measures included length of hospital stay, critical care requirements, re-admission rate, medical complications and mortality rates. Results. A total of 1914 THA and 2537 TKA procedures were evaluated. In THA, the higher dose of TXA was associated with a significant reduction in transfusion (p = 0.02, risk ratio (RR) 0.74, 95% confidence interval (CI) 0.58 to 0.96) and rate of re-admission (p < 0.001, RR 0.50, 95% CI 0.35 to 0.71). There were reductions in the requirement for critical care (p = 0.06, RR 0.55, 95% CI 0.31 to 1.00), and in the length of stay from 4.7 to 4.3 days (p = 0.02). In TKA, transfusion requirements (p = 0.049, RR 0.64, 95% CI 0.41 to 0.99), re-admission rate (p = 0.001, RR 0.56, 95% CI 0.39 to 0.80) and critical care requirements (p < 0.003, RR 0.34, 95% CI 0.16 to 0.72) were reduced with the higher dose. Mean length of stay reduced from 4.6 days to 3.6 days (p < 0.01). There was no difference in the incidence of deep vein thrombosis, pulmonary embolism, gastrointestinal bleed, myocardial infarction, stroke or death in THA and TKA between cohorts. Conclusion. We suggest that a single pre-operative dose of TXA, 30 mg/kg, maximum 2.5g, results in a lower transfusion requirement compared with a lower dose in patients undergoing elective primary hip and knee arthroplasty. However, these findings should be interpreted in the context of the retrospective non-randomised study design. Cite this article: R. J. M. Morrison, B. Tsang, W. Fishley, I. Harper, J. C. Joseph, M. R. Reed. Dose optimisation of intravenous tranexamic acid for elective hip and knee arthroplasty: The effectiveness of a single pre-operative dose. Bone Joint Res 2017;6:499–505. DOI: 10.1302/2046-3758.68.BJR-2017-0005.R1

Joint hemiarthroplasty replaces one side of a synovial joint and is a viable alternative to total joint arthroplasty when one side of the joint remains healthy. Most hemiarthroplasty implants used in current clinical practice are made from stiff materials such as cobalt chrome or ceramic. The substitution of one side of a soft cartilage-on-cartilage articulation with a rigid implant often leads to damage of the opposing articular cartilage due to the resulting reductions in contact area and increases in cartilage stress. The improvement of post-operative hemiarthroplasty articular contact mechanics is of importance in advancing the performance and longevity of hemiarthroplasty. The purpose of the present study was to investigate the effect of hemiarthroplasty surface compliance on early in-vitro cartilage wear and joint contact mechanics. Cartilage wear tests were conducted using a six-station pin-on-plate apparatus. Pins were manufactured to have a hemispherical radius of curvature of 4.7 mm using either Bionate (DSM Biomedical) having varying compliances (80A [E=20MPa], 55D [E=35MPa], 75D [E=222MPa], n=6 for each), or ceramic (E=310GPa, n=5). Cartilage plugs were cored from fresh unfrozen bovine knee joints using a 20 mm hole saw and mounted in lubricant-containing chambers, with alpha calf serum diluted with phosphate buffer solution to a protein concentration of 17 g/L. The pins were loaded to 30N and given a stroke length of 10 mm for a total of 50,000 cycles at 1.2 Hz. Volumetric cartilage wear was assessed by comparing three-dimensional cartilage scans before and during wear testing. A two-way ANOVA was used for statistical analysis. To assess hemiarthroplasty joint contact mechanics, 3D finite element modelling (ABAQUS v6.12) was used to replicate the wear testing conditions. Cartilage was modeled using neo-Hookean hyper-elastic material properties. Contact area and peak contact stress were estimated. The more compliant Bionate 80A and 55D pins produced significantly less volumetric cartilage wear compared with the less compliant Bionate 75D and ceramic pins (p 0.05). In terms of joint contact mechanics, the more compliant materials (Bionate 80A and 55D) had significantly lower maximum contact stress levels compared to the less compliant Bionate 75D and ceramic pins (p < 0 .05). The results of this study show a relationship between hemiarthroplasty implant surface compliance and early in vitro cartilage wear, where the more compliant surfaces produced significantly lower amounts of cartilage wear. The results of the joint contact mechanics analysis showed that the more compliant hemiarthroplasty materials produced lower maximum cartilage contact stresses than the less compliant materials, likely related to the differences in wear observed. More compliant hemiarthroplasty surfaces may have the potential to improve post-operative cartilage contact mechanics by increasing the implant-cartilage contact area while reducing peak contact stress at the implant-cartilage interface, however, such materials must be resistant to surface fatigue and longer-term cartilage wear/damage must be assessed

Up to 40% of patients are using opioids at the time of joint replacement surgery in the USA despite emerging evidence suggesting opioids are ineffective for chronic non-cancer pain. Our primary objective was to determine if preoperative opioid use among patient awaiting total knee arthroplasty (TKA) was associated with worse patient-reported outcomes (PRO) measures at one-year follow-up when compared to non-opioid users, after adjusting for age, gender, and comorbidities. The study linked Alberta's Pharmacy Information Network (PIN) data with prospectively collected Alberta Bone and Joint Health Repository administrative data (medical and PRO data) for patients who underwent primary TKA in Alberta from 2013–2015. The PIN contains prescribing information from physician offices and pharmacies across Alberta. Preoperative ‘opioid users’ were defined as having 90-days of consistent opioid use in the 180-days prior TKA, and ‘opioid-exposed’ subjects had recorded opioid prescriptions in the 180-days prior to TKA, but did not meet the definition of an opioid user. Those with no opioid-exposure in the 180-days pre-TKA were deemed a ‘non-opioid user’. We used multiple linear regression to examine how preoperative opioid use (opioid user, opioid-exposed, non-opioid user) impacted Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores at one year after TKA after adjusting for confounding variables. These included age, sex, preoperative WOMAC scores, comorbidities including depression, diabetes, obesity, stroke, pulmonary disease, renal disease, cardiac disease, liver disease, and overall comorbid burden. Of the 2182 unique cases identified, 151 (7%) were opioid users, 527 (24%) opioid-exposed and 1504 (69%) non-opioid user. Opioid users were more likely to be prescribed strong opioids (e.g., hydromorphone, oxycodone) compared to with opioid-exposed subjects (p < 0 .001) and had a median morphine equivalent dose of 30.7 mg/day compared with the opioid-exposed group (2.2 mg/day, p < 0 .001) in the 180-days prior to TKA. Opioid users, in the 180-days prior to TKA had an active opioid prescription for a mean duration of 153 days (95CI 149, 157) within the 180-days prior to TKA, compared to 34 days (95CI 32, 37) for opioid-exposed (p < 0 .001). In the parsimonious pain and function models, opioid use, lower preoperative WOMAC score, depression, and obesity were associated with worse one-year pain and function. Patients prescribed preoperative opioids had worse WOMAC scores one-year after TKA respectively when compared to non-opioid users, after adjusting for other factors (opioid user pain score: −9.5, function score: −9.4, opioid exposed pain score: −2.6, function score: −3.6, p < 0 .001 for all). Further, opioid users with a concomitant diagnosis of depression had significantly worse one-year postoperative WOMAC scores when compared to non-depressed non-opioid users (scores −14, p < 0 .001 for both pain and function). In Alberta, 31% of patients were prescribed opioids within 180-days before TKA, preoperative opioid use was associated with worse one-year postoperative WOMAC pain and function scores relative to non-opioid users. Our results suggest that strategies to reduce preoperative opioid use could improve patient outcomes after TKA, and support the most recent Canadian opioid prescribing guidelines that attempt to minimize opioid use for chronic conditions such as arthritis