Aim. Treatment recommendations for periprosthetic joint infections (PJI) include surgical debridement, antibiotic therapy or staged revision. In surgical related foot and ankle infections (SR-FAI), implant removal will lead to instability. Debridement is difficult because the implant is outside the joint. Recommendations regarding PJI treatment can therefore not be extrapolated to the treatment of SR-FAI. Method. We searched PubMed for the etiology and treatment of SR-FAI, taken into account the time of occurrence, causative microorganisms and surgical treatment options. We integrated this knowledge into a treatment algorithm for SR-FAI. Results. Within the first 6 weeks after surgery, it is difficult to distinguish acute osteomyelitis from surgical site infection in which infection is limited to the soft tissue. The predominantly causative microorganism is Staphylococcus aureus. No debridement can be performed, because of the diffuse soft tissue inflammation and the absence of a joint space. If early SR- FAI is suspected without signs of systemic symptoms, fistula or abscess, empirical antibiotic treatment covering Staphylococcus aureus is recommended. If there is suspicion of ongoing SR-FAI after 2 weeks of empirical treatment, samples for culture after an antibiotic free window should be obtained to identify the causative microorganisms. If SR-FAI is confirmed, but there is no consolidation yet, targeted antibiotic treatment is given for 12 weeks without initial implant removal. In all other cases, debridement and samples for culture should be obtained after an antibiotic free window. Staged revision surgery will be performed if there is still a nonunion. Conclusions. Treatment algorithm regarding PJI cannot be extrapolated to the treatment of SR-FAI. Until now, no treatment guideline for SR-FAI is available. We have introduced a treatment algorithm for the treatment of SR-FAI. The guideline will be validated during the next 2 years

External validation of machine learning predictive models is achieved through evaluation of model performance on different groups of patients than were used for algorithm development. This important step is uncommonly performed, inhibiting clinical translation of newly developed models. Recently, machine learning was used to develop a tool that can quantify revision risk for a patient undergoing primary anterior cruciate ligament (ACL) reconstruction (https://swastvedt.shinyapps.io/calculator_rev/). The source of data included nearly 25,000 patients with primary ACL reconstruction recorded in the Norwegian Knee Ligament Register (NKLR). The result was a well-calibrated tool capable of predicting revision risk one, two, and five years after primary ACL reconstruction with moderate accuracy. The purpose of this study was to determine the external validity of the NKLR model by assessing algorithm performance when applied to patients from the Danish Knee Ligament Registry (DKLR). The primary outcome measure of the NKLR model was probability of revision ACL reconstruction within 1, 2, and/or 5 years. For the index study, 24 total predictor variables in the NKLR were included and the models eliminated variables which did not significantly improve prediction ability - without sacrificing accuracy. The result was a well calibrated algorithm developed using the Cox Lasso model that only required five variables (out of the original 24) for outcome prediction. For this external validation study, all DKLR patients with complete data for the five variables required for NKLR prediction were included. The five variables were: graft choice, femur fixation device, Knee Injury and Osteoarthritis Outcome Score (KOOS) Quality of Life subscale score at surgery, years from injury to surgery, and age at surgery. Predicted revision probabilities were calculated for all DKLR patients. The model performance was assessed using the same metrics as the NKLR study: concordance and calibration. In total, 10,922 DKLR patients were included for analysis. Average follow-up time or time-to-revision was 8.4 (±4.3) years and overall revision rate was 6.9%. Surgical technique trends (i.e., graft choice and fixation devices) and injury characteristics (i.e., concomitant meniscus and cartilage pathology) were dissimilar between registries. The model produced similar concordance when applied to the DKLR population compared to the original NKLR test data (DKLR: 0.68; NKLR: 0.68-0.69). Calibration was poorer for the DKLR population at one and five years post primary surgery but similar to the NKLR at two years. The NKLR machine learning algorithm demonstrated similar performance when applied to patients from the DKLR, suggesting that it is valid for application outside of the initial patient population. This represents the first machine learning model for predicting revision ACL reconstruction that has been externally validated. Clinicians can use this in-clinic calculator to estimate revision risk at a patient specific level when discussing outcome expectations pre-operatively. While encouraging, it should be noted that the performance of the model on patients undergoing ACL reconstruction outside of Scandinavia remains unknown

Concepts in glenoid tracking and treatment strategies of glenoid bone loss are well established. Initial observations in our practice in Singapore showed few patients with major bone loss requiring glenoid reconstructions. This led us to investigate the incidence of and the extent of bone loss in our patients with shoulder instability. Our study revealed bony Bankart lesions were seen in 46% of our patients but glenoid bone loss measured only 6–10% of the glenoid surface. In the same study we found that arthroscopic labral repair with capsular plication and Mason-Ellen suturing (Hybrid technique) was sufficient to stabilise patients with bipolar bone defects and minor glenoid bone loss. This led us to develop the concept of minor bone loss and a new algorithm. Our algorithm and strategies to deal with major bone loss will also be discussed, and techniques & outcomes of Arthroscopic Bony Bankart repair, Arthroscopic Glenoid Reconstruction and Arthroscopic Remplissage procedures will be shown

Modifying Knee anatomy during mechanical Total Knee Arthroplasty (TKA) may impact ligament balance, patellar tracking and quadriceps function. Although well fixed, patients may report high levels (20%) of dissatisfaction. One theory is that putting the knee in neutral mechanical alignment may be responsible for these unsatisfactory results. Kinematic TKA has gained interest in recent years; it aims to resurface the knee joint and preservation of natural femoral flexion axis about which the tibia and patella articulate, recreating the native knee without the need for soft tissue relaease. That's being said, it remains the question of whether all patients are suitable for kinematic alignment. Some patients' anatomy may be inherently biomechanically inferior and recreating native anatomy in these patients may result in early implant failure. The senior author (PAV) has been performing Kinematic TKA since 2011, and has developed an algorithm in order to better predict which patient may benefit from this technique. Lower limb CT scans from 4884 consecutive patients scheduled for TKA arthroplasty were analysed. These exams were performed for patient-specific instrumentation production (My Knee®, Medacta, Switzerland). Multiple anatomical landmarks used to create accurate CT-based preoperative planning and determine the mechanical axis of bone for the femur and tibia and overall Hip-knee-Ankle (HKA). We wanted to test the safe range for kinematic TKA for the planned distal resection of the femur and tibia. Safe range algorithm was defined as the combination of the following criteria: – Independent tibial and femoral cuts within ± 5° of the bone neutral mechanical axis and HKA within ± 3°. The purpose of this study is to verify the applicability of the proposed safe range algorithm on a large sample of individual scheduled for TKA. The preoperative tibial mechanical angle average 2.9 degrees in varus, femoral mechanical angle averaged 2.7 degrees in valgus and overall HKA averaged of 0.1 in varus. There were 2475 (51%) knees out of 4884, with femur and tibia mechanical axis within ±5° and HKA within ±3° without need for bony corrections. After applying the algorithm, a total of 4062 cases (83%) were successfully been evaluated using the proposed protocol to reach a safe range of HKA ±3° with minimal correction. The remaining 822 cases (17%) could not be managed by the proposed algorithm because of their unusual anatomies and were dealt with individually. In this study, we tested a proposed algorithm to perform kinematic alignment TKA avoiding preservation/restoration of some extreme anatomies that might not be suitable for TKA long-term survivorship. A total of 4062 cases (83%) were successfully eligible for our proposed safe range algorithm for kinematic TKA. In conclusion, kinematically aligned TKA may be a promising option to improve normal knee function restoration and patient satisfaction. Until we have valuable data confirming the compatibility of all patients' pre arthritic anatomies with TKA long-term survivorship, we believe that kinematically alignment should be performed within some limits. Further studies with Radiostereometry or longer follow up might help determine if all patients' anatomies are suitable for Kinematic TKA

Bone age is a radiographical assessment used in pediatric medicine due to its relative objectivity in determining biological maturity compared to chronological age and size.1 Currently, Greulich and Pyle (GP) is one of the most common methods used to determine bone age from hand radiographs.2–4 In recent years, new methods were developed to increase the efficiency in bone age analysis like the shorthand bone age (SBA) and the automated artificial intelligence algorithms. The purpose of this study is to evaluate the accuracy and reliability of these two methods and examine if the reduction in analysis time compromises their accuracy. Two hundred thirteen males and 213 females were selected. Each participant had their bone age determined by two separate raters using the GP (M1) and SBA methods (M2). Three weeks later, the two raters repeated the analysis of the radiographs. The raters timed themselves using an online stopwatch while analyzing the radiograph on a computer screen. De-identified radiographs were securely uploaded to an automated algorithm developed by a group of radiologists in Toronto. The gold standard was determined to be the radiology report attached to each radiograph, written by experienced radiologists using GP (M1). For intra-rater variability, intraclass correlation analysis between trial 1 (T1) and trial 2 (T2) for each rater and method was performed. For inter-rater variability, intraclass correlation was performed between rater 1 (R1) and rater 2 (R2) for each method and trial. Intraclass correlation between each method and the gold standard fell within the 0.8–0.9 range, highlighting significant agreement. Most of the comparisons showed a statistically significant difference between the two new methods and the gold standard; however it may not be clinically significant as it ranges between 0.25–0.5 years. A bone age is considered clinically abnormal if it falls outside 2 standard deviations of the chronological age; standard deviations are calculated and provided in GP atlas.6–8 For a 10-year old female, 2 standard deviations constitute 21.6 months which far outweighs the difference reported here between SBA, automated algorithm and the gold standard. The median time for completion using the GP method was 21.83 seconds for rater 1 and 9.30 seconds for rater 2. In comparison, SBA required a median time of 7 seconds for rater 1 and 5 seconds for rater 2. The automated method had no time restraint as bone age was determined immediately upon radiograph upload. The correlation between the two trials in each method and rater (i.e. R1M1T1 vs R1M1T2) was excellent (κ= 0.9–1) confirming the reliability of the two new methods. Similarly, the correlation between the two raters in each method and trial (i.e. R1M1T1 vs R2M1T1) fell within the 0.9–1 range. This indicates a limited variability between raters who may use these two methods. The shorthand bone age method and an artificial intelligence automated algorithm produced values that are in agreement with the gold standard Greulich and Pyle, while reducing analysis time and maintaining a high inter-rater and intra-rater reliability

Introduction. The functional ante-inclination (AI) of the cup after total hip arthroplasty (THA) is a key component in the combined sagittal index (CSI) to predict joint stability after THA. To accurately predict AI, we deducted a mathematic algorithm between the radiographic anteversion (RA), radiographic inclincation (RI), pelvic tilting (PT), and AI. The current study aims (1) to validate the mathematic algorithm; (2) to convert the AI limits in the CSI index (standing AI ≤ 45°, sitting AI ≥ 41°) into coronal functional safe zone (CFSZ) and explore the influences of the stand-to-sit pelvic motion (PM) and pelvic incidence (PI) on CFSZ; (3) to locate a universal cup orientation that always fulfill the AI criteria of CSI safe zone for all patients or subgroups of PM(PM ≤ 10°, 10° < PM ≤ 30°, and PM > 30°) and PI (PI≤ 41°, 41°< PI ≤ 62°, and PI >62°), respectively. Methods. A 3D printed phantom pelvic model was designed to simulate changing PT values. An acetabular cup was implanted with different RA, RI, and PT settings using robot assisted technique. We enrolled 100 consecutive patients who underwent robot assisted THA from April, 2019 to June, 2019 in our hospital. EOS images before THA and at 6-month follow-up were collected. AI angles were measured on the lateral view radiographs as the reference method. Mean absolute error (MAE), Bland-Altman analysis and linear regression were conducted to assess the accuracy of the AI algorithm for both the phantom and patient radiographic studies. The 100 patients were classified into three subgroups by PM and PI, respectively. Linear regression and ANOVA analysis were conducted to explore the relationship between the size of CFSZ, and PM and PI, respectively. Intersection of the CFSZ was conducted to identify if any universal cup orientation (RA, RI) existed for the CSI index. Results. The mathematic algorithm for calculating AI based on RI, RA, and PT is highly accurate according to the phantom and patient radiographic study. CFSZ size corresponds linearly with PM (R² = 0.638) and PI (R² = 0.129), respectively. There are significant differences in the size of CFSZ, as well as in the intersection of CFSZ and LSZ, between the subgroups of PM and PI, respectively (P<0.017). There is no universal cup orientations could be identified to fulfill the AI limits of the CSI index for all the 100 patients or any of the three subgroups, according to either PM or PI. Conclusions. The cup target orientation should be individualized. The validated algorithm between AI and RA, RI, and PT parameters can serve as the quantitative tool for patient-specific optimization of functional cup AI in different postures

Use of “CPR” distance has proven clinical utility in stratifying risks of “steep cups” in MOM failures.[1, 4] The CPR indice has been defined as distance between point of intersection of the hip reaction force (Fig. 1: vector-R in contact patch) and closest point on the inner cup rim.[4] However, the CPR indice has limitations. It assumes that, (1) the hip load-vector (R) will be angled 10°-medial in all patients, (2) the contact patch will be same size in all patients, and (3) the contact patch will be invariant with increasing MOM diameter. In contrast it is known from retrieval studies that larger MOM bearings created much larger wear patches.[3] Furthermore, the size of cup wear-patches in MOM bearings can now be estimated with some certainty using simulator wear data.[2] Our objective was to develop an algorithm that would predict (i) contact-patch size for all cup designs and diameters, (ii) determine actual margin of safety (Fig. 1: MOS) for different laterally-inclined cups, and (iii) predict critical test angles for “steep” cup studies in hip simulators. The ‘CPR-distance’ (Fig. 1) is subtended by the CPA angle, but the true margin of safety is the distance from edge of wear patch to cup rim, indicated here by MOS angle. In this algorithm the wear-patch size (CAP angle) is a key parameter, as derived from MOM wear data (Fig. 2). The CAP angles decrease with increasing MOM diameter, as defined by strong linear trend (R=0.998). The key 2nd parameter is cup inclination angle that juxtaposes the wear-pattern to the cup rim (CCI). For hemispherical cups the critical inclination is given by CCI = 90 – CAP/2, where articulation angle ABA = 180o. The cup bearing-surface is typically reduced < 180o(sub-hemispherical profile, instrumentation groove, rim bevel, etc). These effects are grouped under ‘rim-detail’, as defined by RD = (180-ABA)/2 (Fig. 1). Thus critical inclination any cup is given by CCI = 90o – (CAP/2) – RD = (ABA – CAP)/2. The margin-of-safety (Fig. 1) is then represented by the equation MOS = 100 – (CIA + CAP/2 + RD). Applicability of the new algorithm can be visualized with a 48mm MOM (cup ABA=160o) run in a standard simulator test (Fig. 3). The algorithm predicts that with cup at 40o inclination there is good margin of safety (11.8o), representing a 5mm distance. This would become much reduced at CIA = 50o, while true edge-wear appears at the 60o test inclination (Fig. 3. EW = −8.2o). For clinical comparison with ‘CPR-distances’, the algorithm shows that positioning the wear patch 10o-medial (Figs. 1, 3) has margin of safety averaging 11.5 mm (MOS) less than was predicted by the CPR indice. While CPR has shown clinical utility, it is believed that compensating for actual size of cup wear-patterns provides a more realistic risk assessment for different MOM diameters in different cup positions. Thus the new algorithm permits accurate depiction of cup wear-patterns for use in both clinical and simulator studies

Aims. Ilizarov described four methods of treating non-unions but gave little information on the specific indications for each technique. He claimed, ‘infection burns in the fire of regeneration’ and suggested distraction osteogenesis could effectively treat infected non-unions. This study investigated a treatment algorithm for described Ilizarov methods in managing infected tibial non-union, using non-union mobility and segmental defect size to govern treatment choice. Primary outcome measures were infection eradication, bone union and ASAMI bone and function scores. Patients and Methods. A consecutive series of 79 patients with confirmed, infected tibial non-union, were treated with one of four Ilizarov protocols, consisting of; monofocal distraction (26 cases), monofocal compression (19), bifocal compression/distraction (16) and bone transport (18). Median non-union duration was 10 months (range 2–168). All patients had undergone at least one previous operation (mean 2.2; range 1–5), 38 had associated limb deformity and 49 had non-viable non-unions. Twenty-six cases (33%) had a new simultaneous muscle flap reconstruction at the time of Ilizarov surgery and 25 had pre-existing flaps reused. Treatment algorithm based on assessment of bone gap and non-union stiffness, measured after resection of non-viable bone. Results. The treatment algorithm was easy to apply, being based on easily assessable criteria. Infection was eradicated in 76 cases (96.2%) at a mean follow-up of 40.8 months (range 6–131). All three cases of infection recurrence occurred in the monofocal compression group. They required repeat excision and Ilizarov distraction in two cases and below-knee amputation in one. Union was achieved in 68 cases (86.1%) with the initial Ilizarov methods alone. Union was highest amongst the monofocal distraction and bifocal compression/distraction groups, 96.2% and 93.8% respectively. Mean external fixator time was 7.5 months (range 3–17). Monofocal compression was successful in only 73.7% of mobile non-unions, with significantly lower ASAMI scores and a 26.3% re-fracture rate. Bone transport secured union in 77.8% (14/18) but with a 44.4% unplanned reoperation rate. However, after further treatment, infection-free union following bone transport was 100%. Conclusion. We cannot recommend Ilizarov monofocal compression in the treatment of infected, mobile non-unions. Distraction (monofocal or bifocal) was effective and is associated with higher rates of union and infection clearance

The most common classification of periprosthetic femoral fractures is the Vancouver classification. The classification has been validated by multiple centers. Fractures are distinguished by location, stability of the femoral component, and bone quality. Although postoperative and intraoperative fractures are classified using the same three regions, the treatment algorithm is slightly different. Type A fractures involve the greater and lesser trochanter. Fractures around the stem or just distal to the stem are Type B and subcategorised depending on stem stability and bone quality. Type C fractures are well distal to the stem and are treated independent of the stem with standard fixation techniques. The majority of fractures are either B1 (stable stem) or B2 (unstable stem). The stem is retained and ORIF of the fracture performed for B1 fractures. B2 and B3 fractures require stem revision with primary stem fixation distal to the fracture. Intraoperative fractures use the same A, B, C regions but are subtyped 1–3 as cortical perforations, nondisplaced, and displaced unstable fractures, respectively. With the exception of A1 intraoperative fractures all other intraoperative fractures require surgical treatment. A recent publication utilizing a New York state registry highlighted the patient risk of mortality associated with periprosthetic hip fractures. One month, 6 month and 1 year mortality was 3.2%, 3.8% and 9.7%, respectively. The mortality risk was lower for periprosthetic fractures treated with ORIF at 1 and 6 months compared to fractures requiring revision total hip

Metal-on-metal bearings (MoM), in both a total hip and resurfacing application, saw an increase in global utilization in the last decade. This peaked in 2008 in the US, with approximately 35% of bearings being hard-on-hard (metal-on-metal or ceramic-on-ceramic). Beginning in 2008, reports in the orthopaedic literature began to surface regrading local soft tissue reactions and hypersensitivity to metal-on-metal bearings. A major implant manufacturer recalled a resurfacing device in 2010 after national joint registries demonstrated higher than expected revision rates. Patients with painful metal-on-metal bearings presenting to the orthopaedic surgeon are a difficult diagnostic challenge. The surgeon must go back to basic principles, perform a complete history and physical exam, obtain serial radiographs and basic bloodwork (ESR, CRP) to rule out common causes of pain and determine if the pain is, or is not, related to the bearing. The Asymptomatic MoM Arthroplasty: Patients will present for either routine followup, or because of concerns regarding their bearing. It is important to emphasise that at this point the vast majority of patients with a MoM bearing are indeed asymptomatic and their bearings are performing well. The surgeon must take into account: a) which specific implant are they dealing with and what is its track record; b) what is the cup position; c) when to perform metal ion testing; d) when to perform further soft tissue imaging (MARS MRI, Ultrasound); e) when to discuss possible surgery. A simple algorithm for both painless and painful MoM Arthroplasties has been developed and will be presented

The best algorithm, measurements, and criteria for screening children with Down syndrome for upper cervical instability are controversial. Many authors have recommended obtaining flexion and extension views. We noted that patients who require surgical stabilization due to myelopathy or cord compression typically have grossly abnormal radiographic measurements on the neutral upright lateral cervical spine radiograph (NUL). This study was designed to determine whether a full series of cervical spine images including flexion/extension lateral radiographs (FEL) was important to avoid missing upper cervical instability. This is a retrospective evaluation of cervical spine images obtained between 2006 and 2012 for the purposes of “screening” children with Down syndrome for evidence of instability. The atlanto-dental interval, space available for cord, and basion axial interval were measured on all films. The Weisel-Rothman measurement was made in the FEL series. Clinical outcome of those with abnormal measurements were reviewed. Sensitivity, specificity, positive and negative predictive values of NUL and FEL x-rays for identifying clinically significant cervical spine instability were calculated. Two-hundred and forty cervical spine series in 213 patients with Down syndrome between the ages of four months and 25 years were reviewed. One hundred and seventy-two children had a NUL view, and 88 of these patients also had FEL views. Only one of 88 patients was found to have an abnormal ADI (≥6mm), SAC (≤14mm), or BAI (>12mm) on an FEL series that did not have an abnormal measurement on the NUL. This patient had no evidence of cord compression or myelopathy. Obtaining a single NUL x-ray is an efficient method for radiographic screening of cervical spine instability. Further evaluation may be required if abnormal measurements are identified on the NUL x-ray. We also propose new “normal” values for the common radiographic measurements used in assessing risk of cervical spine instability in patients with Down syndrome

Functional approaches for the localisation of the hip centre (HC) are widely used in Computer Assisted Orthopedic Surgery (CAOS). These methods aim to compute the HC defined as the centre of rotation (CoR) of the femur with respect to the pelvis. The Least-Moving-Point (LMP) method is one approach which consists in detecting the point that moves the least during the circumduction motion. The goal of this paper is to highlight the limits of the native LMP (nLMP) and to propose a modified version (mLMP). A software application has been developed allowing the simulation of a circumduction motion of a hip in order to generate the required data for the computation of the HC. Two tests have been defined in order to assess and compare both LMP methods with respect to (1) the camera noise (CN) and (2) the acetabular noise (AN). The mLMP and nLMP error is respectively: (1) 0.5±0.2mm and 9.3±1.4mm for a low CN, 21.7±3.6mm and 184.7±13.1mm for a high CN, and (2) 2.2±1.2mm and 0.5±0.3mm for a low AN, 35.2±18.5mm and 13.0±8.2mm for a high AN. In conclusion, mLMP is more robust and accurate than the nLMP algorithm

Introduction. John Insall described medial release to balance the varus knee; the release he described included releasing the superficial MCL in severe varus cases. However, this release can create instability in the knee. Furthermore, this conventional wisdom does not correct the actual pathology which normally exists at the joint line, and instead it focuses on the distal end of the ligament where there is no pathology. We have established a new protocol consisting of 5 steps to balance the varus knee without releasing the superficial MCL and we tried this algorithm on a series of 115 patients with varus deformity and compared it to the outcome with a similar group that we have performed earlier using the traditional Insall technique. Material and method. 115 TKR were performed by the same surgeon using Zimmer Persona implant in varus arthritic knees. The deformities ranged from 15 to 35 degrees. First, the bony resection was made using Persona instrumentation as recommended by the manufacturer. The sequential balancing was divided into 5 steps (we will show a short video demonstrating the surgical techniques for each step) as follows:. Step 1: Releasing of deep MCL Step 2: Excising of osteophyte. Step 3: Excising of scarred tissue in the posteromedial corner soft phytes Step 4: Excision of the posteromedial capsule in case of flexion contracture Step 5: Releasing the semi-membranous (in gross deformity). We used soft tissue tensioner to balance the medial and lateral gaps. When the gaps are balanced at early step, there was no need to carry on the other steps. We used only primary implant and we did not have to use any constrained implant. We have compared this group with a similar group matched for deformity from previous 2 years where the conventional medial release as described by Insall. Results. We could balance all knees without releasing the superficial MCL ligament as follows:. -In[H1] 31 cases, we were able to balance the knees performing step 1 and step 2 only. -In 35 cases, we had to do step three in addition to 1 and 2 to achieve balance of cases. -In 25 cases, we performed step 4- those cases had pre-operative flexion contracture. -We had to proceed to step 5 only in 14 cases. These patients had the worst deformity in the group. We have used primary TKR in all cases; in 83 cases, we used a CR implant and in the rest, we used PS implant. Comparing this to the earlier conventional release we had to use 11 CCK implant on severe cases. Patient satisfaction was better with the new algorithm group when compared with the traditional release. Preserving the superficial MCL allowed us to maintain stability post-operatively and allowed us to use minimum constraint such as CR in severe deformity. Discussion. Many literatures have confirmed that cutting superficial MCL causes major medial instability after TKA. Releasing or pie crusting the superficial MCL can cause MCL insufficiency. Our protocol enable the surgeon to tackle the pathology rather than take a short-cut and releasing the superficial MCL. Reserving the superficial MCL allowed us to use minimal constraint even in severe deformity of 40 degrees of varus deformity. The conventional release has resulted in some cases instability, forcing us to use higher constraint such as CCK. Conclusion. Although releasing the superficial MCL has been described in different ways in multiple literature, little attention has been paid to the pathology of the posteromedial corner. This paper clearly shows that the complex anatomy of the posteromedial corner require us to pay better attention and this paper present better algorithm reserving the superficial MCL and enabling us to correct the deformity and balancing the soft tissue without instability. We strongly recommend surgeons not to release the superficial MCL because this will create instability in some cases

Background. In the United Kingdom, over 1 million elective surgeries were cancelled due to COVID-19, resulting in over 1.9 million people now waiting more than 4 months for their procedure – 3x the number last year. To address this backlog, the healthcare service has been asked to develop locally-designed ‘COVID-light’ facilities. In our local system, 822 patients awaited orthopaedic surgery when elective surgery was permitted to resume. The phased return of service required a careful and pragmatic prioritisation of patients, to protect resources, patients, and healthcare workers. Aims. We aim to describe how the COVID-19 Algorithm for Resuming Elective Surgery (CARES) was used to consider 1) Which type of operation and patient should be prioritised? and 2) Which patients are safe to undergo surgery? The central tenets to this were patient safety, predicted efficacy of the surgery, and delivering compassionate care by considering biopsychosocial factors. Methods. Orthopaedic surgeons were provided with details of patients on their waiting list. They prioritised patients into those for surgery within 1 month (. Urgent. : e.g. arthroplasty for rapid deterioration from avascular necrosis or infection, or in the lowest quartile of Oxford Hip/Knee/Shoulder scores), < 3 months (. Soon. : e.g. revision or second-stage arthroplasty), and > 3 months (arthroplasty for end-stage arthrosis). The surgeon-led stratification was then reviewed by a multidisciplinary surgical prioritisation team, including anaesthetists and operating theatre managers, to consider medical history, the need for additional intraoperative services (such as cardiac physiologists, or specialist equipment requiring industry ‘reps’), and the risk of postoperative deterioration requiring HDU/ICU. The MDT also reviewed what the impact of disease and further delay may have on a patient's mental health, ability to work, or ability to care for dependents. The CARES protocol created an aggregate score for efficacy, compassion, safety and surgical risk to equitably rank patients. Results. The implementation of CARES stratified the waiting list into 122 (14.8%) patients requiring urgent surgery, with high likely health-gain or biopsychosocial gain, of whom 76 were low-risk and 46 were high-risk – medically moribund or complex. There were 232 (28.2%) patients required surgery within 3 months, and 468 (57.1%) patients were deemed safe to delay for > 3months. Alongside i) staff- and patient-screening, ii) adequate personal protective equipment, and iii) increased used of regional anaesthesia, the healthcare system was reconfigured, to create two surgical pathways. ‘Green Well’ patients were scheduled for surgery at a clean site – an elective surgical centre with no on-site HDU/ICU. ‘Green High-Risk’ patients underwent surgery at the general hospital (with on-site HDU/ICU) in operating rooms (ORs) which were physically segregated from ‘Red’ ORs reserved for COVID-19+ or trauma patients. In 6 weeks, 164 patients underwent surgery with no transmission of COVID-19 between patients or staff. Conclusion. Our healthcare system safely resumed elective surgery as early as the top 2% of hospitals nationally. This was facilitated by CARES stratification (which factors safety, efficacy, and compassion), MDT-led decisions, and surgical pathway reconfiguration. This generalisable, validated approach could be widely applied to facilitate restarts globally

Background. Establishing the diagnosis in a child presenting with an atraumatic limp can be difficult. Clinical prediction algorithms have been devised to distinguish septic arthritis (SA) from transient synovitis (TS). Within Europe measurement of the Erythrocyte Sedimentation Rate (ESR) has largely been replaced with assessment of C-Reactive Protein (CRP) as an acute phase protein. We produce a prediction algorithm to determine the significance of CRP in distinguishing between TS and SA. Method. All children with a presentation of ‘atraumatic limp’ and a proven effusion on hip ultrasound between 2004 and 2009 were included. Patient demographics, details of the clinical presentation and laboratory investigations were documented to identify a response to each of the four variables (Weight bearing status, WCC >12,000 cells/m3, CRP >20mg/L and Temperature >38.5°C). SA was defined based upon culture and microscopy of the operative findings. Results. 311 hips were included within the study. Of these 282 were considered to have transient synovitis. 29 patients met criteria to be classified as SA based upon laboratory assessment of the synovial fluid. The introduction of CRP eliminated the need for a four variable model as the use of two variables (CRP and weight bearing status) had similar efficacy. Treating individuals who were non-weight-bearing and a CRP >20mg/L as SA correctly classified 94.8% individuals, with a sensitivity of 75.9%, specificity of 96.8%, positive predictive value of 71.0%, and negative predictive value of 97.5%. CRP was a significant independent predictor of septic arthritis. Conclusions. CRP was a strong independent risk factor of septic arthritis, and its inclusion within a regression model simplifies the diagnostic algorithm. Nevertheless, this and other models are generally more reliable in excluding SA, than confirming SA, and therefore a clinician's acumen remains important in identifying SA in those individuals with a single abnormal variable

Treatment of Tendo Achilles (TA) ruptures can result in considerable morbidity and has significant socio-economic implications. The ideal management of these injuries has yet to be defined. Recent studies have demonstrated that non-surgical treatment with accelerated rehabilitation may have comparable outcomes to surgery. The aim of this study was to evaluate current management and outcomes of TA ruptures at a tertiary referral centre, with a view to developing contemporary treatment guidelines. A retrospective review of TA ruptures over a 12-month period was undertaken. Patients were managed on an individual based approach with no strict management algorithm followed. Data collection included pre-injury activity level, ultrasound findings and treatment methodology. Outcome data collected included return to activity, incidence of DVT and re-rupture. Patients were followed up for an average of 2 years. Data was collected in 49 patients. 31 (63%) of these were managed non-surgically. Ruptures were most common in men (65%) at an average age of 44 yrs. Ultrasound scan at initial diagnosis was performed in 28 patients. There was an average gap in equinus of 34mm in the surgical group, while the average gap within the non-surgical group was 24mm (p=0.23). There was no association between the gap observed on ultrasound and re-rupture rate. At a median of 2 year follow up, there was no significant reduction in average time spent immobilised in a below knee splint in the surgically treated group (10.2 weeks) compared to non-surgical group (10.9 weeks, p=0.35). 86.3% of patients returned to pre-injury level of activity in the non-surgical group and 86.7% in the surgery group (p=1.0). Complications within this patient cohort consisted of one superficial wound infection and one re-rupture, both occurring within the surgical group. Within the surgical group patients were treated with direct primary repair or primary reconstruction using FHL augmentation in cases of delayed presentation. DVT was not observed in either group. Only 22.6% received thromboprophylaxis in non-surgical group compared to 61.1% in surgical group. We observed that patients within the non-surgical group demonstrated the same return to pre-injury activity as the surgically treated group and had fewer complications. The time spent immobilised was also comparable. Based on these findings, we modified guidelines and now recommend that surgery should be limited to patients with gap of greater than 20 mm in full equinus on ultrasound and in those with delayed diagnosis. We also recommend thromboprophylaxis for 2 weeks in non-surgical group

Introduction. Fixed Flexion deformity (FFD) is a common deformity amongst patients due to undergo TKR. For their correction surgical algorithm is documented. Resection of distal femur and clearing off posterior recess are two essential steps. In balancing these knees it is suggested to resect extra distal Femur to gain extension space. Aim. To demonstrate full FFD correction without resecting extra distal Femur. Methods. In this prospective study during the yr. 2009–2010 32 cases were recruited. All the cases were performed by the author and a PS design of the implants were used. Inclusion Criteria. All cases of Gr2 deformities. (OA or Inflammatory arthropathy.). Exclusion Criteria. Patients with h/o previous injury, fractures, surgery (ies). Surgical Technique. Distal Femur is resected as per distal thickness of the implant to be inserted (9 to 11mm). Standard Tibial cut & Femoral AP cut are made using the mechanical jigs. Thus flexion and extension spaces are created. If extension space is tight at this stage, Posterior release is done. Posterior osteophytes are resected and capsule is reflected off the posterior Femur. If FFD still persists then temptation to resect extra distal femur is avoided. A further more aggressive posterior release is performed. In stepwise manner following structures are addressed. Posterior ledge of the femoral condyles is resected with a curved osteotome. Capsule is reflected further proximally and if need be then resected horizontally at the level of the Tibial resection. Thus extension space is equalized to the flexion space. (Video clipping). Results. Out of 32 Knees 24 were OA and 8 Inflammatory arthropathy. 27 pt.s were females and 5 were males. Mean age at operation 64.5 years (52.1 to 82.7 yrs) Pre op KSS score was 51 (28 to68). Mean post op KSS 90 (72 to 96). All but 2 pt.s had full correction of FFD intra op and remained corrected at mean average follow up of 1yr. The patients maintained a night splint for 1 month. They were encouraged to perform static and dynamic quadriceps exercise from day 1. 2 patients had residual 5 degree FFD at the end of the operation. Of this 1 patient was neutral at 1 yr. follow up. One continued to have 5 degrees FFD. Discussion. FFDs correction requires a careful planning of surgical steps. In following Gap balancing technique, to achieve extension space sometimes there can be erroneous Distal Femoral resection. We have demonstrated here that by addressing posterior structures more aggressively we can achieve extension space equal to flexion space. There are certain advantages of not resecting extra distal Femur namely…. No elevation of Joint line and hence preventing Midflexion laxity. Mismatch of components size of femur and Tibia is prevented. In very small knees (Asian patients) damage to collateral ligament insertion is prevented. Conclusion. In this study all the patients had full correction. There are clear advantages of not resecting extra distal Femur. We continue to use this technique for Gr.2 FFDs. We suggest change in the current algorithm for correction by not removing extra distal femur

Introduction. The application of digital radiography in orthopaedic settings has facilitated the improvement in the retention and utilization of these images in pre and post-operative assessments [1]. In addition to the cost-effectiveness of such technology the use of digital imaging combined with advanced computer image processing software such as TraumaCadTM software system (TraumaCad, BRAINLAB, Westchester, IL, USA) can provide more accurate details about patients in total hip replacement arthroplasty (THA), a process traditionally called preoperative templating [2] by which intraoperative complications are minimized and overall surgical time is reduced[3]. In a study of 486 patients we demonstrated that patients demographic had significant effect on the outcome of the measurement and utilizing them in a predictive model had helped with improving the results [4]. In this study, we aimed to improve and optimize the proposed algorithm by utilizing more patients’ information and improving the model by using a nonlinear relationship. Our main hypothesis in this study was that the model would significantly predict the actual implant size based on the preoperative assessments. Method. We analyzed the outcome of digital radiographs of 1018 patients who were treated with THA. Minimum. Maximum. Mean. Std. Deviation. Templated Acetabulum Size. 44.00. 64.00. 54.12. 4.05. Height (m). 147.32. 202.20. 172.02. 10.73. Weight (kg). 39.10. 139.10. 84.44. 19.67. BMI. 15.48. 43.06. 28.33. 5.18. Acetabular Size. 44.00. 64.00. 54.25. 3.75. Digital radiographs were acquired in the anteroposterior view of the pelvis centered over the pubic symphysis. The hip was internally rotated 10° to 15°. We evaluated multiple interactions and nonlinear models and developed the most significant model based on the available clinical data. Results. We derived the following equation based on the model presented by the multiple regression analysis. Act[estimated]=−9.0467–0.35*Act[temp]+34.79*Height−0.35*Weight+1.32*BMI+0.01* (Act[temp])∘2–3.56*Height∘2–0.01*BMI∘2. In which Act[estimated] is the estimated size of acetabulum cup, Act[temp] is the preoperative templated acetabulum size from digital radiography, Height was in m and Weight was in kg. Figure 1 and Figure 2 depicts the residual assessments of the model. Figure 3 depicts the range of effects by each factor. Discussion. Patients’ specific data would improve the preoperative accuracy by more than 5% within one size of the actual acetabular component size. This improvement in accuracy translates into significant cost saving in THA cases as the cost of implant inventory could be significantly minimized. In our practice based on these assessments we use customized patients trays to reduce intraoperative costs

Cementless femoral components have an excellent track record that includes efficient implantation and long-term survival, thus are the predominant stem utilised in North America. Femoral component stability and resistance to subsidence are critical for osseointegration and clinical success. Implant design, surgical technique, anatomic fit, and patient characteristics, such as bone quality, can all effect initial implant stability and resistance to subsidence. Variability in stem shape and in the anatomy of the proximal femoral metaphysis has been implicated in the failure of some stem designs. Biologic fixation obtained with osseointegration of cementless implants may improve implant longevity in young, active, and obese patients. Lack of intimate fit can lead to clinical complications such as subsidence, aseptic loosening, and peri-prosthetic fracture. Currently, there are several stem designs, all of which aim to achieve maximal femoral stability and minimal subsidence and include: Fit and Fill / Double Taper Proximally Porous Coated Stems; Parallel Sided Taper Wedge or “Blade” Stems; Wagner Style Conical Shape Splined Titanium Stems; Tapered Rectangular Cross-Section Zweymuller Stem; Fully-Porous Coated Stems; Modular Proximal Sleeve Fluted Stem; Anatomic Proximally Porous Coated Stems. The majority of patients with relatively straightforward anatomy can be treated with any of the aforementioned femoral implant types. However, more complicated femoral anatomy frequently requires a particular implant type to maximise stability and promote osseointegration. Stems with femoral deformity in the meta-diaphyseal region may require a shorter stem in order to avoid an osteotomy. Distorted femoral anatomy typically seen in childhood diseases, such as dysplasia, may require a modular proximal sleeve tapered fluted stem or Wagner style cone stem to impart optimal stem anteversion separate from the native femoral neck version. The most severe forms of dysplasia may require a shortening osteotomy and subsequent distal fixation and neck version flexibility, which can be addressed with a modular proximal sleeve fluted or fully porous coated stem. A stovepipe or osteoporotic femur may require a stem that engages more distally such as a conical splined tapered stem, a fully porous coated stem or even a cemented stem to achieve adequate stability. Finally, obese patients are a particular challenge and emerging data suggests that a morphologically based parallel-sided taper wedge stems may confer greater stability and resistance to subsidence in these patients. Ultimately, an appropriate selection algorithm will facilitate an appropriate match of the patient morphology with femoral implant geometry that facilitates stable fixation and osseointegration

Aims. Microbiological diagnosis of bone and joint infections (BJIs) is pivotal. However, no consensus exists about the best choice for techniques to be used and the best indications for molecular methods. Our objectives were: (i) to compare the performance of various microbiological diagnostic methods (cultural and molecular) on synovial fluid specimens and (ii) to select an algorithm for optimizing the diagnosis of BJIs in adults. Methods. This prospective multicentric study (in Lyon and Saint-Etienne, France) included 423 joint fluid samples, collected from 333 adult patients (median age 69 years) suspected for BJI on the basis of medical history and clinical symptoms. For each inclusion, joint fluid and blood culture were collected concomitantly. The synovial fluid was also inoculated into blood culture bottles. Cytology, culture (using 5 solid media and an enrichment broth, incubated for 15 days), universal 16S rRNA PCR and PCR targeting Staphylococcus spp, S.aureus, Streptococcus spp, S.pneumoniae, Kingella kingae, Borrelia burgdorferi and Propionibacterium acnes were systematically performed on synovial fluid. Results. Prosthetic materials were present in 65.0% of the cases and 31.7% of the patients had received antibiotics in the 15 days before puncture. Out of 423 joint fluids, 265 (62.6%) were positive by at least one diagnostic technique (cultural or molecular): 219 mono- and 46 poly-microbial, for a total of 322 bacteria. Identified bacteria were staphylococci in 54.0%, streptococci-enterococci in 15.2%, Gram-negative bacilli in 14.0%, anaerobic species in 10.9% and other bacteria in 5.9% of cases. Comparing the individual performance of each cultural technique, blood culture bottles showed the highest rate of positivity (detecting 61.4 and 58.4% of the bacteria, for the paediatric and anaerobic bottles, respectively) but cannot be performed alone and require to be combined with solid media. The 16S rDNA PCR was positive in only 49.2% of the cases whereas higher detection was obtained with specific PCR. Blood cultures performed concomitantly with joint puncture were positive in only 9.7% of the cases. Conclusions. In order to simplify the culture procedures and to precise the place of PCR for synovial fluid, we propose the following algorithm: joint fluids should be inoculated onto 3 solid media (blood and chocolate agars for 2 days, anaerobic blood agar for 10 days), associated with inoculation into blood culture bottles for 10 days. If culture remains negative, 16S rDNA PCR and/or Staphylococcus PCR should be added. Applying this algorithm on our cohort, 93.6% of the bacteria would have been detected