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

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

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

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

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

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

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

Background. Standard preoperative protocols in total joint arthroplasty utilize the International Normalized Ratio (INR) to determine patient coagulation profiles. However, the relevance of preoperative INR values in joint arthroplasty remains controversial. Acceptable INR cutoff values for joint replacement are inconsistent, and are often based on studies of primary arthroplasty, or even non-orthopedic procedures. This analysis examined the relationship between preoperative INR values and post-operative outcomes in revision total hip arthroplasty (rTHA). Optimal cutoff INR values correlated with specific outcomes were subsequently determined. Methods. The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) was retrospectively queried for revision total hip arthroplasty procedures performed between 2006 and 2017. Patients with a preoperative INR collected no later than 1 day prior to surgery were further stratified for analysis. INR values which correlated with specific outcomes were determined using receiver operating characteristics (ROC) curves for each outcome of interest. The optimal cutoff INR value for each outcome was then obtained using univariate and multivariate models which determined INR values that maximized both sensitivity and specificity. Results. There were a total of 11,393 patients who underwent a revision total hip arthroplasty from 2006–2017 recorded in NSQIP. Of the 2,012 patients who met inclusion and exclusion criteria, 858 had an INR < 1.0, 931 had an INR > 1.0 to 1.25, 175 had an INR > 1.25 to 1.5, and 48 patients had an INR > 1.5. Patients with progressively higher INR values had a significantly different risk of mortality within 30 days (p=0.005), bleeding requiring transfusion (p< 0.001), sepsis (p=0.002), stroke (p<0.001), failure to wean from ventilator within 48 hours (p=0.001), readmission (p=0.01), and hospital length of stay (p< 0.001). Similar results were obtained when utilizing optimal INR cutoff values. When correcting for other factors, the following poor outcomes were significantly associated with the respective INR cutoff values (Estimate, 95% CI, p value): LOS (1.67, 1.34–2.08, p <0.001), bleeding requiring transfusion (1.65, 1.30–2.09, p<0.001), sepsis (2.15, 1.11–4.17, p 0.02), and any infection (1.82, 1.01–3.29, p 0.04). Conclusions. INR values >1.65, >1.67, >1.82, and >2.15 were correlated with increased transfusion requirements, LOS, any infection, and sepsis respectively. Therefore, even subtherapeutic elevations in INR may predict poor outcomes following revision total joint replacement. Surgeons and perioperative medical specialists should consider more stringent INR goals when optimizing patients prior to revision arthroplasty. Level of Evidence. Prognostic Level IV. For any figures or tables, please contact authors directly

Purpose. Total knee replacement is the one of the most performed surgeries. However, patient's satisfaction rate is around 70–90 % only. The sacrifice of cruciate ligament might be the main reason, especially in young and active patients. ACL stabilizes the knee by countering the anterior displacing and pivoting force, absorbs the shock and provides proprioception of the knee. However, CR knees has been plagued by injury of PCL during the surgery and preservation of the ACL is a demanding technique. Stiffness is more common comparing to PS designed knee. To insert a tibial baseplate with PE is usually thicker than 8 mm comparing to 2–4 mm of removed tibial bone. The stuffing of joint space may put undue tension on preserved ACL and PCL. Modern designed BCR has been pushed onto market with more sophisticated design and instrumentation. However, early results showed high early loosening rate. Failure to bring the tibia forward during cementing may be the main cause. The bone island where ACL footprint locates is frequently weak, intraoperative fracture happens frequently. A new design was developed by controlled elevation and reattachment of the ACL footprint to meet all the challenges. Method. A new tibial baseplate with a keel was designed. The central part of the baseplate accommodates elevated bony island with ACL footprint. The fenestrations at the central part is designed for reattachment of bony island under proper tension with heavy sutures and fixed at anterior edge of the baseplate in suture bridge fashion and also for autograft to promote bony healing after reattachment. The suture bridge method has been used by arthroscopists for ACL avulsion fracture without the need of immobilization. The elevation of bony island release the tension in the ACL which come from stuffing of baseplate and PE insert and greatly facilitate cementing of the baseplate. The keel improve the weakness of traditional U shape design of BCR knees. Instead of keeping the bony island intact by separately cutting the medial and lateral tibial plateau in BCR knees in the past, we choose to saw the tibial plateau in one stroke as in PS knees, then removes the two condyles. The bony island includes the footprint both ACL and PCL. The central part of tibial baseplate will push the bony island upward which release the undue tension in the cruciate ligaments. Summary. We proposed a new solution for the kinematic conflict in the present bi-cruciate knee designs by elevation and re- attachment of bony island with ACL footprint at the same time simplify the ACL preservation. The simple tibial cutting procedure also facilitate the process. The technique protects PCL from injury during tibial bone cutting in CR knees. We believe the new BCR design has the potential to replace CR knee in term of function and longevity in the future

Heterotopic ossification (HO) is a relatively common complication of total hip arthroplasty (THA), but is rather rare after total knee arthroplasty (TKA). In both cases, it is usually asymptomatic and is most commonly identified as an incidental finding on post-operative radiographs. However, in severe cases it can result in decreased range of motion and pain. There are several risk factors that have been shown to be associated with development of HO. These include male gender, ceramic-on-ceramic bearings, prior stroke, and hypertrophic osteoarthritis. Heterotopic ossification can be treated with physical therapy during the maturation phase (12 to 24 weeks), but surgical intervention is required if the stiffness persists. All heterotopic bone should be excised with careful attention to neurovascular structures. Patients should begin prophylaxis following HO excision and prior to any subsequent surgeries. Heterotopic ossification prophylaxis consists of NSAIDs, radiotherapy, or a combination of both modalities. These therapies are not without complications, therefore, routine administration of prophylaxis for all patients is not indicated. Several new pathways of inhibiting extra-skeletal bone formation in HO are under investigation (retinoid acid receptor agonists, apyrase, and LDN-193189). Future studies should focus on identification of patients at risk for HO as well as better therapeutic options with less side effects

Aims

This study aimed to investigate the risk of postoperative complications in COVID-19-positive patients undergoing common orthopaedic procedures.

Venous thromboembolism (VTE) prophylaxis following total joint arthroplasty (TJA) should be individualised in order to maximise the efficacy of prophylactic measures while avoiding the adverse events associated with the use of anticoagulants. At our institution, we have developed a scoring model using the Nationwide Inpatient Sample (NIS) database, which is validated against our institutional data, to stratify patients into low- and high-risk groups for VTE. Low-risk patients are placed on aspirin 81 mg twice daily for four weeks post-operatively, and high-risk patients are placed on either a Vitamin K antagonist (warfarin), low molecular weight heparin, or other oral anticoagulants for four weeks post-operatively. All patients receive sequential pneumatic compression devices post-operatively, and patients are mobilised with physical therapy on the day of surgery. Patients who have a history of peptic ulcer disease or allergy to aspirin are also considered for other types of anticoagulation following surgery. Risk Stratification Criteria. Major comorbid risk factors utilised in our risk stratification model include history of hypercoagulability or previous VTE, active cancer or history of non-cutaneous malignancy, history of stroke, and pulmonary hypertension. We consider patients with any of these risk factors at elevated risk of VTE and therefore candidates for formal anticoagulation. Other minor risk factors include older age, bilateral surgery compared with unilateral, inflammatory bowel disease, varicose veins, obstructive sleep apnea, and history of myocardial infarction, myeloproliferative disorders, and congestive heart failure. Each minor criterion is associated with a score. The cumulative score is compared with a defined threshold and the score that surpasses the threshold indicates that the patient should receive post-operative anticoagulation. To facilitate the use of this scoring system, an iOS mobile application (VTEstimator) has been developed and can be downloaded from the app store

Objective. The efficacy and safety of tranexamic acid (TXA) on reducing blood loss and transfusion has been confirmed in primary total hip arthroplasty (THA). The main methods of administration includes intravenous, topical alone or combined use, and the most appropriated methods remains undecided. This study was aimed to compare the efficacy and safety of different methods of TXA following primary THA. Methods. We prospectively collected patients' data through National Health Database from January 2013 to December 2016. The patients were divided into control group, intravenous group, topical group and combined group according to the different methods of TXA. The primary outcome was the incidence of transfusion and venous thromboembolism. Secondary outcomes were total blood loss, hemoglobin level on postoperative day 3 and decrease in hemoglobin, incidence of wound complications and other adverse events. Results. A total of 7537 primary THA procedures were collected, 4102 with TXA, 3435 without TXA. 2847 (37.8%) patients received intravenous TXA alone, 235 (3.1%) patients received topical TXA alone and 1020 (13.5%) patients received combined use. The transfusion rate decreased from 33.07% to 12.7% with the use of TXA (p< 0.001). The transfusion rate was 30.21% in topical group, 10.68% in intravenous group, and 14.31% in combined group, with a significant difference between treatment groups (p< 0.01 for all). The hemoglobin on postoperative day 3 in control group was 91.24±17.09 g/L, which was significantly lower than that in topical group (101.38±16.71 g/L), intravenous group (102.79±32.37 g/L) and combined group (104.34±16.67 g/L, p<0.05 for all). The hemoglobin drop on POD 3 in control group was 38.07±18.10 g/L, which was significantly higher than that in topical group (30.02±17.11 g/L), intravenous group (29.35±16.05 g/L) and combined group (29.22±16.37 g/L, p<0.05 for all). The total blood loss in control group was (1377.74 ± 851.97 ml), which was significantly higher than that in topical group (1123.15±628.59 ml), intravenous group (971.08±671.39 ml) and combined group (946.4±724.82 ml, p<0.05 for all). A total of 14 DVT (0.41%) in control group, 4 patients (0.1%) in TXA group occurred DVT, and the difference was significant (0.10%, p= 0.006). Cardiac infarction occurred in 3 patients (0.04%), stroke occurred in 2 patients (0.03%), and 3 patients (0.04%) developed wound infection. No episode of PE or death occurred. Conclusion. TXA was effective and safe to decrease blood loss and transfusion following primary THA no matter of intravenous, topical use alone or combined use. In order to achieve better hemostatic effect, intravenous or combined application was recommended if no contradictions were found

Background. Venous thromboembolism (VTE) is a common, costly, and morbid complication following TJA. Consequently, the current standard of care recommends that all TJA candidates receive some form of thromboprophylaxis postoperatively. Chemoprophylaxis, however, is not without its own risks and has been associated with greater risk of perioperative complications such as major bleeding, infection, stroke, and increased wound drainage. Mechanical compression devices serve as an alternative to chemoprophylaxis. Compression devices are thought to function by decreasing venous stasis and activating fibrinolysis. Intermittent pneumatic compression devices (IPCD) function by providing pressure at a constant cycle; whereas continuous enhanced circulation therapy (CECT) devices such as ActiveCare portable system (Medical Compression Systems, Or Akiva, Israel) function in a synchronized manner with the patient's own respiratory cycles. While both of these systems are widely utilized, there is scarce data comparing their effectiveness as thromboprophylatic agents following TJA. The purpose of this meta-analysis is to comparatively evaluate the efficacy of ActiveCare to IPCDs in the prevention of thromboembolic events following TJA. Methods. A literature search using PubMed, Cochrane, and EMBASE databases were used to identify all articles published between January 2000 and August 2016. Key words used to conduct the search were venous foot pump, intermittent pneumatic compression, total hip arthroplasty/replacement, total knee arthroplasty/replacement, deep vein thrombosis, thromboembolic disease and pulmonary emboli. Two independent investigators carried out the literature review using the PRISMA guidelines (Figure 1). Analysis of risk ratio was performed by evaluation of studies which compared IPCD with any control chemoprophylaxis regiment or ActiveCare with any control chemoprophlaxis regiment. Assessment of heterogeneity and analysis of data were operated by Review Manager 5.3. Results. Our primary search protocol yielded 968 individual studies by both reviewers of which 525 were duplicates. After screening the remaining 443 abstracts for relevancy 357 were excluded, leaving 86 for full text examination. After a thorough evaluation, 60 were further excluded, and a total of 24 studies, published between 2000 and 2014, were included for analysis, representing 9,134 patients. Of these, 13 were randomized controlled trials and 11 were retrospective studies. When compared to control chemoprophylactic groups, the risk ratio (RR) of DVT development was 0.51 (95% CI: 0.39 – 0.67; I. 2. =69%) with NSIPCDs and 0.47 (95% CI: 0.27 – 0.80; I. 2. =0%) with RSCDs. The RR for development of PE in these groups respectively were 0.24 (95% CI: 0.04 – 0.15) versus 0.55 (95% CI: 0.35 – 0.88) (Figure 3). Conclusion. When compared to chemoprophylaxis alone, compression devices appear to reduce the incidence of VTEs following TJA. The addition of mechanical prophylaxis to any chemoprophylactic regimen increased VTED prevention Following a comparative analysis of IPCDs and ActiveCare our study suggests that ActiveCare may be more effective at preventing VTE events, albeit not statistically significant. Thus, our results demonstrate that while both devices are effective thromboprophylactic modalities, more research is warranted to better elucidate the strengths and limitations of compression devices as thromboprophylatic agents. For any figures or tables, please contact the authors directly

Aims

As an alternative to external fixators, intramedullary lengthening nails (ILNs) can be employed for distraction osteogenesis. While previous studies have demonstrated that typical complications of external devices, such as soft-tissue tethering, and pin site infection can be avoided with ILNs, there is a lack of studies that exclusively investigated tibial distraction osteogenesis with motorized ILNs inserted via an antegrade approach.

Acute peri-operative blood loss warranting transfusion is a frequent consequence of major joint replacement (TJR) surgery. Significant peri-operative anemia can contribute to hypotension, dyspnea, coronary ischemia and other peri-operative medical events that can result in increased risk of peri-operative complications, readmissions and impair the patient's ability to mobilise after surgery resulting in a longer length of stay (LOS) and increase skilled nursing facility (SNF) utilization. The risks associated with allogeneic blood transfusions (ABT) administered to treat symptomatic peri-operative anemia are numerous and extend beyond the concerns of transmission of communicable disease (HIV, hepatitis, other). Patients receiving ABTs have been shown to have a longer hospital LOS, higher risk of infection, and higher mortality after TJR than those who do not require transfusion after surgery. As a result, many different pre-operative, peri-operative and post-operative strategies have been utilised to minimise peri-operative blood loss and transfusion need for patients undergoing TJR. Several studies have shown that the strongest predictor of the need for ABT in the TJR patient is the pre-operative hematocrit (Hct). As a result, all patients with unexplained pre-operative anemia should be evaluated for an underlying cause prior to elective TJR surgery. In recent years, focus has shifted towards peri-operative reduction of blood loss with the use of pharmacologic agents like tranexamic acid (TXA). These agents work by inhibiting fibrinolysis and activating plasminogen. Numerous studies have shown that TXA given IV, applied topically into the surgical wound or given orally have been shown to reduce peri-operative bleeding and ABT after both THA and TKR. Regardless of route of administration, all appear to be more efficacious and considerably more cost-effective in reducing the need for ABT than other methods discussed previously. Despite concerns about the potential increased thromboembolic risk in patients undergoing TJR, there does not appear to be any conclusive evidence suggesting an increased risk of venous thromboembolic disease (VTED) in TJR patients who receive peri-operative TXA. Although it may be unnecessary, many TJR surgeons still, however, avoid use of TXA in patients with a past history of VTED, stroke, coronary artery disease (including coronary stents), renal insufficiency, hypercoagulable state and seizure disorder. The use of topical TXA may be safer in some of these high risk patients since systemic absorption is minimal when administered via this route. Although the optimal method of administration (IV, topical, oral or combined) has not yet been determined based on safety, cost and reduction of need for ABT, incorporation of tranexamic acid into a blood conservation program is clearly the standard of care for all TJR programs that should nearly eliminate the need for ABT for patients undergoing TJR

Background. Intravenous and topical tranexamic acid (TXA) has become increasingly popular in total joint arthroplasty to decrease perioperative blood loss. In direct comparison, the outcomes and risks of either modality have been found to be equivalent. In addition, current literature has also demonstrated that topical TXA is safe and effective in the healthy population. To our knowledge, there is a scarcity of studies demonstrating the safety of topical TXA in high risk patient populations undergoing total joint arthroplasty or revision joint arthroplasty. The purpose of this study is to determine the safety of topical TXA in patients undergoing total or revision arthroplasty that are also on chronic anticoagulant or anti-platelet therapy. Methods. We performeded a retrospective review of patients undergoing primary and revision total hip or knee arthroplasties that received topical TXA (3g/100mL NS) from November 2012 to March 2015. All patients, regardless of co-morbidities, were included in the study population. Patients were divided into 3 groups:. Group 1: Patients without any antiplatelet or anticoagulant therapy within 90 days of surgery. Group 2: Patients receiving antiplatelet therapy (Aspirin and/or Plavix) within 90 days of surgery. Group 3: Patients receiving anti-coagulant therapy within 90 days of surgery (low molecular weight heparin, unfractionated heparin, warfarin, dabigatran, rivaroxaban, apixaban). Chart review analyzing ICD-9 and ICD-10 coding was then utilized to establish any peri-operative complications within the 30 day post-operative period in all groups. Complications amongst the groups were evaluated via chi-squared testing as well as multivariate linear regression. Review of current literature and CMS protocols were used to establish reportable peri-operative complications. Wound infections, thromboembolic events and vascular complications such as myocardial infarction, pulmonary embolism, deep venous thrombosis, stroke, aortic dissection were included. Results. During the study period, a total 1471 total joint arthroplasties were performed on 1324 patients (88.7% knee arthroplasty, 11.3% hip arthroplasty). Group 1 included 1033 patients who were not on any prior anti-platelet or anticoagulant therapy. Group 2 included 254 patients receiving chronic antiplatelet therapy 90 days prior to surgery. Group 3 included 184 patients receiving chronic anticoagulant therapy 90 days prior to surgery. No statistically significant differences were found between the groups for any of the included peri-operative complications. The most common complication occurring amongst all the groups was superficial wound infection, which occurred in a total of 60 (4.1%) patients in contrast to 18 (1.2%) patients who sustained an acute deep peri-prosthetic infection. Twenty (1.4%) patients sustained an ultrasound proven deep vein thrombosis, with the highest prevalence occurring in those patients receiving no anticoagulation prior to surgery (15/20, 75%), however this was not statistically significant following linear regression analysis. Conclusions. To our knowledge, this is the first study that demonstrates that topical tranexamic acid is safe to use in so-called high risk patients who are being treated prior to surgery with anti-platelet or anti-coagulation therapy

Introduction. Hemiarthroplasty is an attractive technique for young and active patients as it preserves more bone stock. Polycarbonate urethane (PCU) has recently been introduced as an alternative bearing material. DSM Biomedical BV (Geleen, The Netherlands) has modified Bionate. ®. PCU 80A (80AI) with C18 groups and produce Bionate. ®. II PCU 80A (80AII) to create a different biointerface and enhance its tribological properties. The aim of this study was to compare friction performance of the articulation of the cartilage against 80AI and 80AII in various lubricants. Materials and Methodology. A customised multidirectional pin-on-plate reciprocating rig (Fig. 1) was used to perform friction tests of ovine femoral condyles as they articulated against PCU 80A discs (diameter 38 mm, thickness 3.2 mm). The average surface roughness of the cartilage and the PCU discs was approx. 450 nm and 10 nm respectively. 30% (v/v) bovine calf serum (BCS) and bovine synovial fluid (BSF) were used as lubricants. Prior to testing, each disc was fully hydrated in its test lubricant for 6 days. During testing, a static compressive load of 20 N was applied (an average stress of approx. 0.95 MPa). The sliding distance was 25 mm with ±15° rotation over the length of the stroke to produce cross shear. Each test lasted 15 h at a frequency of 1 Hz. Lubricant was kept at 37±1 °C throughout testing. The friction force was measured using full-bridge circuit strain gauges (Fig. 1). Results. The COF steadily increased during the first hour of testing due to the biphasic nature of the cartilage and then stabilized. Fig. 2 shows the average COF (mean ± 95% confidence limits, n=6) over 15 h. When BSF was used, the average COF decreased from 0.379±0.015 to 0.286±0.039 for 80AI and from 0.316±0.014 to 0.190±0.029 for 80AII, which found to be statistically significant (p = .004 and p < .0005 respectively). In both lubricants, the average COF for 80AII was statistically lower than that for 80AI (p < .0005 for BCS and p = .004 for BSF). Conclusion. Under the clinically-relevant conditions, the average COF varied with tested lubricants and polymers. The average COF reduced for both polymers when BSF was used. This might be because proteoglycan 4 (PRG4) adsorbs on cartilage surface [1], and thus possibly lowered the COF outcomes. In addition to PRG4, other molecules present in BSF (i.e. hyaluronan and lipids) might also have roles in reduced COF. Moreover, 80AII had a lower friction than 80AI as either lubricant was used. This can be attributed to the higher protein adsorption nature of 80AII, though further investigation is required. Furthermore, when BCS was used the mean COF for 316L stainless steel (0.358±0.032) was lower than that for 80AI (0.379±0.015), which was not statistically different (p = 0.277), and it was greater than that for 80AII (0.316±0.014), which was statistically significant (p = 0.039). In conclusion, 80AII showed statistically superior friction performance over 80AI and SS316L, which would be a potential hemiarthroplasty material among these three