The aim of this study was to determine the long term 20 year survival and outcomes of high tibial osteotomy (HTO). 100 consecutive subjects underwent HTO under the care of a single surgeon between 2000 and 2002, consented to participation in a prospective study and completed preoperative WOMAC scores. Subjects were reviewed at 10 years, and again at a minimum of 20 years after surgery. PROMS included further surgery, WOMAC scores, Oxford Knee Score (OHS), KOOS, and EQ-5D, and satisfaction with surgery. 20 year survival was assessed with Kaplan-Meir analysis, and failure defined as proceeding to subsequent knee arthroplasty. The mean age at HTO was 50 years (range 26-66), and 72% were males. The 5, 10, and 20 year survival of the HTO was 88%, 76%, 43% respectively. On multiple regression analysis HTO failure was associated with poor preoperative WOMAC score of 45 or less (HR 3.2, 95% CI 1.7-6.0, p=0.001), age at surgery of 55 or more (HR 2.3, 95% CI 1.3-4.0, p=0.004), and obesity (HR 1.9, 95% CI 1.1-3.4, p=0.023). In patients who met all criteria of preoperative WOMAC score of 45 or less, age <55 years and body mass index of <30 HTO survival was 100%, 94%, and 59% at 5, 10 and 20 years respectively. Of those who had not proceeded to TKA the mean Oxford Score was 40, KOOS Pain score was 91 and KOOS function score was 97. 97% reported they were satisfied with the surgery and 88% would have the same surgery again under the same circumstances. At 20 years after HTO 43% had not proceeded to knee arthroplasty, and were continuing to demonstrate high subjective scores and satisfaction with surgery. HTO survival was higher in those under 55 years, with BMI <30 and baseline WOMAC score of >45 at 59% HTO survival over 20 years. HTO may be considered a viable procedure to delay premature knee arthroplasty in carefully selected subjects

Increasing femoral offset in total hip replacement (THR) has several benefits including improved hip abductor strength and enhanced range of motion. Biomechanical studies have suggested that this may negatively impact on stem stability. However, it is unclear whether this has a clinical impact. Using data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), the aim of this study was to determine the impact of stem offset and stem size for the three most common cementless THR prostheses revised for aseptic loosening. The study period was September 1999 to December 2020. The study population included all primary procedures for osteoarthritis with a cementless THR using the Corail, Quadra-H and Polarstem. Procedures were divided into small and large stem sizes and by standard and high stem offset for each stem system. Hazard ratios (HR) from Cox proportional hazards models, adjusting for age and gender, were performed to compare revision for aseptic loosening for offset and stem size for each of the three femoral stems. There were 55,194 Corail stems, 13,642 Quadra-H stem, and 13,736 Polarstem prostheses included in this study. For the Corail stem, offset had an impact only when small stems were used (sizes 8-11). Revision for aseptic loosening was increased for the high offset stem (HR=1.90;95% CI 1.53–2.37;p<0.001). There was also a higher revision risk for aseptic loosening for high offset small size Quadra-H stems (sizes 0-3). Similar to the Corail stem, offset did not impact on the revision risk for larger stems (Corail sizes 12-20, Quadra-H sizes 4-7). The Polarstem did not show any difference in aseptic loosening revision risk when high and standard offset stems were compared, and this was irrespective of stem size. High offset may be associated with increased revision for aseptic loosening, but this is both stem size and prosthesis specific

This study aimed to examine the effect of high tibial osteotomy (HTO) on the ankle and subtalar joints via analysis of static radiographic alignment. We hypothesised that surgical alteration of the alignment of the proximal tibia would result in compensatory distal changes. 35 patients recruited as part of the wider Biomechanics and Bioengineering Centre Versus Arthritis HTO study between 2011 and 2018 had pre- and postoperative full-length weightbearing radiographs taken of their lower limbs. In addition to standard alignment measures of the limb and knee (mechanical tibiofemoral angle, Mikulicz point, medial proximal tibial angle), additional measures were taken of the ankle/subtalar joints (lateral distal tibial angle, ground-talus angle, joint line convergence angle of the ankle) as well as a novel measure of stance width. Results were compared using a paired T-test and Pearson's correlation coefficient. Following HTO, there was a significant (5.4°) change in subtalar alignment. Ground-talus angle appeared related both to the level of malalignment preoperatively and the magnitude of the alignment change caused by the HTO surgery; suggesting subtalar positioning as a key adaptive mechanism. In addition to compensatory changes within the subtalar joints, the patients on average had a 31% wider stance following HTO. These two mechanisms do not appear to be correlated but the morphology of the tibial plafond may influence which compensatory mechanisms are employed by different subgroups of HTO patients. These findings are of vital importance in clinical practice both to anticipate potential changes to the ankle and subtalar joints following HTO but it could also open up wider indications for HTO in the treatment of ankle malalignment and osteoarthritis

Aim. One of the surgical therapeutic options for periprosthetic joint infection (PJI) includes debridement, antibiotics, and implant retention (DAIR). Prognostically favorable criteria for DAIR include short duration of symptoms, stable implant, pathogen susceptible to a ‘biofilm-active’ antimicrobial agent, and intact soft-tissue conditions. Despite this, there is a proportion of failures after DAIR, possibly because the duration of infection is underestimated. With the hypothesis that the duration of infection correlates with the bacterial load, and hence, the bacterial load is associated with failure after DAIR, we aimed to investigate the association of bacterial load in the sonication fluid of mobile parts and clinical outcome after DAIR. Method. From our PJI cohort (2010–2021), patients with DAIR (both palliative and curative approaches) were reviewed retrospectively. Patients with hip, knee or shoulder arthroplasties fulfilling infection definition, available sonication results, and ≥2 years follow-up were included. Sonication results were categorized in ≤ or >1000 cfu/mL. Univariate analysis was performed to identify predictors for DAIR failure. Results. Out of 209 PJIs, we identified 96 patients (100 PJIs, 47.8%) with DAIR. In 67 (69.8%) patients with 71 PJIs, there was a follow-up of ≥2 years. The mean age was 72.7 (SD 12.99) years, 50% were male. The infection affected 36 hips (50.7%), 32 knees (45.1%) and 3 shoulders (4.2%). At follow-up, there were 29 (40.8%) cured and 42 (59.2%) failed cases. When comparing failed and cured cases, we found no difference in comorbidities and previously defined risk factors for PJI, ASA score, Charlson score, anatomic location, no. of previous surgeries, pathogenesis of infection or laboratory values. The proportion of patients with high bacterial load on mobile parts (i.e. >1000 cfu/mL) was significantly higher in the failed DAIR group than it was in the cured group (61.9% vs 20.7%, p<0.001). Conclusions. In this study, a high bacterial load in sonication fluid of mobile parts was associated with failure after DAIR in patients with PJI. Sonication may help to differentiate acute hematogenous seeding to the implant and late reactivation of a previously silent implant-associated infection

Introduction. The management of young patients with painful medial compartment osteoarthritis remains controversial. Opening wedge medial high-tibial osteotomy using a locking plate has shown good results in selected patients. This cohort of patients has high physical demands and previous studies have warned against operating on patients with increased body mass index (BMI). Patients and Methods. Thirty five patients undergoing valgus high tibial osteotomy between Oct 2004 and Feb 2010. Surgical outcome was assessed using Oxford Knee score, pre- and post-operative pain scores, change in employment and patient satisfaction. Results. Mean age at the time of surgery was 41 (22 to 62), mean BMI was 30.9 (21 to 43) and mean Oxford score was 37/48 (16 to 48). Patients rated their overall satisfaction as 7.9/10. Three patients were lost to follow-up, two patients died of unrelated disease. Fifteen (50%) patients had heavy manual jobs and of these 12 (80%) returned to their previous employment post-operatively within 6 months. Seven patients had a BMI > 35 (Mean 39) with a mean weight of 126 Kg (105Kg to 144Kg). These patients had a mean Oxford Score of 42/48 and overall satisfaction of 90%. Pain improved from 8.4/10 pre-op to 1.5/10 post-op (P < 0.0001). None had further procedures. Conclusion. Opening wedge high-tibial osteotomy offers a successful alternative treatment of medial osteoarthritis in young patients with high BMI who place high demands on their knees

Aim. The gold standard treatment for late acute hematogenous (LAH) periprosthetic joint infection (PJI) is surgical debridement, antibiotics and implant retention (DAIR). However, this strategy is still controversial in the case of total knee arthroplasty (TKA) as some studies report a higher failure rate. The aim of the present study is to report the functional outcomes and cure rate of LAH PJI following TKA treated by means of DAIR at a long-term follow-up. Method. A consecutive prospective cohort consisting of 2,498 TKA procedures was followed for a minimum of 10 years (implanted between 2005 and 2009). The diagnosis of PJI and classification into LAH was done in accordance with the Zimmerli criteria (NEJM 2004). The primary outcome was the failure rate, defined as death before the end of antibiotic treatment, a further surgical intervention for treatment of infection was needed and life-long antibiotic treatment or chronic infection. The Knee Society Score (KSS) was used to evaluate clinical outcomes. Surgical management, antibiotic treatment, the source of infection (primary focus) and the microorganisms isolated were also assessed. Results. Among the 2,498 TKA procedures, 10 patients were diagnosed with acute hematogenous PJI during the study period (0.4%). All those 10 patients were operated by means of DAIR, which of course included the polyethylene exchange. They were performed by a knee surgeon and/or PJI surgeon. The failure rate was 0% at the 8.5 years (SD, 2.4) follow-up mark. The elapsed time between primary total knee replacement surgery and the DAIR intervention was 4.7 years (SD, 3.6). DAIR was performed at 2.75 days (SD 1.8) of the onset of symptoms. The most common infecting organism was S. aureus (30%) and E. coli (30%). There were 2 infections caused by coagulase-negative staphylococci and 2 culture-negative PJI. All culture-positive PJI microorganisms were susceptible to anti-biofilm antibiotics. The source of infection was identified in only 3 cases. The mean duration of antibiotic treatment was 11.4 weeks (SD 1.9). The postoperative clinical outcomes were excellent, with a mean KSS of 84.1 points (SD, 14.6). Conclusions. Although the literature suggests that TKA DAIR for acute hematogenous periprosthetic joint infection is associated with high rates of failure, the results presented here suggest a high cure rate with good functional outcomes. Some explanations for this disparity in results may be the correct diagnosis of LHA, not misdiagnosing acute chronic PJI, and a thorough debridement by surgeons specialized in PJI

Objectives. Open fracture classification systems are limited in their use. Our objective was to classify open tibia and femur fractures using the OTS classification system in a region with high incidence of gunshot fractures. One hundred and thirty-seven patients with diaphyseal tibia and femur open fractures were identified from a prospectively collected cohort of patients. This database contained all cases (closed and open fractures) of tibial and femoral intramedullary nailed patients older than 18 years old during the period of September 2017 to May 2021. Exclusion criteria included closed fractures, non-viable limbs, open fractures > 48 hours to first surgical debridement and patients unable to follow up over a period of 12 months (a total of 24). Open fractures captured and classified in the HOST study using the Gustilo-Anderson classification, were reviewed and reclassified using the OTS open fracture classification system, analysing gunshot fractures in particular. Ninety percent were males with a mean age of 34. Most common mechanism was civilian gunshot wounds (gsw) in 54.7% of cases. In 52.6% of cases soft tissue management was healing via secondary intention, these not encompassed in the classification. Fracture classification was OTS Simple in 23.4%, Complex B in 24.1% and 52.6% of cases unclassified. The OTS classification system was not comprehensive in the classification of open tibia and femur fractures in a setting of high incidence of gunshot fractures. An amendment has been proposed to alter acute management to appropriate wound care and to subcategorise Simple into A and B subdivisions; no soft tissue intervention and primary closure respectively. This will render the OTS classification system more inclusive to all open fractures of all causes with the potential to better guide patient care and clinical research

Aim. Periprosthetic joint infection (PJI) and periprosthetic fracture (PF) are one of the most devastating complications in arthroplasty. Each complication by itself is challenging to solve. Yet, simultaneously, both complications are inconceivably complex to deal with, while the treatment regimen of PJI and PF are contradictory. Chronic PJI most often requires implant removal, while PF requires stability, regularly achieved by stable osteosynthesis. This study aims to (1) analyse the success rate of PJI with following concomitant PF during the treatment course in total hip arthroplasties (THA) and (2) to determine the risk factors for reinfection and subsequent revision surgery after treatment of PJI and PF. Method. This restrospective study analyzed 41 patients with concomitant PJI and PF during the PJI treatment period from 2013 to 2022 involving THA. Patients were divided in two cohorts termed success and failure and were statistically compared. The median follow-up time was 66 months (>12 months). All patients were considered individually and treated according to their individual needs in fracture and infection treatment. Re-arthroplasty survival was analyzed using the Kaplan-Meier method. Relevant risk factors were analyzed using the Mann-Whitney test or Chi-square, depending on the variable's scale. Results. The overall success rate of our cohort was 70,7%. Twelve patients required re-operation due to reinfection, resulting in a cumulative 12-month-reinfection rate of 19,5%. The estimated cumulative reinfection free survival rate was 68,3%. Significance in risk factors for failure were found in pathogen virulence grade, Difficult to treat pathogen and number of debridement during interval. On average the Harris Hip score was 66 in the group of reinfection compared to 77 in the group of success. Conclusions. Reoperation and re-infection rate remains high in patients with simultaneous PJI and PF in THA. Due to the heterogeneity of the fractures, soft tissue conditions and pathogens found, treatment must be individualised to salvage the limb. However, small cohorts impact the statistical strength negatively due to instances of two rare complications

Aim. Low-grade infections are difficult to diagnose. As the presence of a chronic infection requires extensive surgical debridement and antibiotic treatment, it is important to diagnose a SII prior to surgery, especially when the hardware is revised. We investigated whether serum inflammatory markers or nuclear imaging can accurately diagnose a chronic spinal instrumentation infection (SII) prior to surgery. Method. All patients who underwent revision spinal surgery after a scoliosis correction between 2017 and 2019 were retrospectively evaluated. The diagnostic accuracy of serum C-reactive protein (CRP) and Erythrocyte Sedimentation Rate (ESR), . 18. F-fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT) and Technetium-99m-methylene diphosphonate (99mTc-MDP) 3-phase bone scintigraphy (TPBS) to diagnose infection were studied. Patients with an acute infection or inadequate culture sampling were excluded. SII was diagnosed if ≥ 2 of the same microorganism(s) were isolated from intra-operative tissue cultures. Results. 31 patients were included. The indication for hardware extraction was pseudoarthrosis in the majority of patients (n = 15). 22 patients (71%) were diagnosed with SII. In all infected cases, Cutibacterium acnes was isolated, including 5 cases with a polymicrobial infection. Sensitivity, specificity, PPV and NPV was: 4.5%, 100%, 100% and 30.0% for CRP >10.0 mg/L, 5.5%, 100%, 100% and 29% for ESR > 30 mm/h; 56%, 80%, 83% and 50% for FDG-PET/CT and 50%, 100%, 100% and 20% for TPBS, respectively. Conclusions. The prevalence of SII in patients undergoing revision spinal surgery is high, with Cutibacterium acnes as the main pathogen. No diagnostic tests could be identified that could accurately diagnose or exclude SII prior to surgery. Future studies should aim to find more sensitive diagnostic modalities to detect low-grade inflammation

Aim. Acute hematogenous periprosthetic joint infection (AHI) is a diagnosis on the rise. The management is challenging and the optimum treatment is not clearly defined. The purpose of this study was to evaluate the characteristics of AHI, and to study risk factors affecting treatment outcome. Methods. We retrospectively analysed 44 consecutive episodes with AHI in a total hip or knee arthroplasty beween 2013 and 2020 at a single center. AHI was defined as abrupt symptoms of infection ≥ 3 months after implantation in an otherwise well functioning arthroplasty. We used the Delphi criteria to define treatment failure with a minimum of 1-year follow-up. Results. AIH was most often caused by Staphylococcus aureus (36%) and streptococcal species (32%), but a broad spectrum of microbes were identified. The majority of patients (25/44) were treated with debridement and retention of the implant (DAIR), with a success rate of 40%, significantly lower than in patients treated with removal of the implant (94%, p=0.001). Staph aureus infections (p=0.004), knee arthroplasties (p=0.03), and implant-age < 2 years (p=0.034) were associated with treatment failure. The 2-year mortality rate was 19%. Conclusions. The main findings in this study were that outcome following DAIR in AHIs is poor, that the majority of infections were caused by virulent microbes, and we found a high mortality rate. Removal of the implant should more often be considered

Aim

The most frequent mechanical failure in the osteosynthesis of intertrochanteric fractures is the cut-out. Fracture pattern, reduction quality, tip-apex distance or the position of the cervico-cephalic screw are some of the factors that have been associated with higher cut-out rates. To date, it has not been established whether underlying bacterial colonization or concomitant infection may be the cause of osteosynthesis failure in proximal femur fractures (PFF). The primary objective of this study is to assess the incidence of infection in patients with cut-out after PFF osteosynthesis.

Aim. The purpose of this study is to analyze the demographic and microbiological variables of acute ankle infections posterior to ankle osteosynthesis and to determine the different characteristics of patients withE. cloacae infection. Method. A multicenter retrospective observational study (4 national hospitals) of acute post osteosynthesis infections of ankle fracture operated between 2015 and 2018 was implemented. The demographic and microbiological variables relating to the surgical intervention and the antibiotic treatment performed were collected. A descriptive assessment of all the variables and a univariate comparison between patients with E. cloacae infection and patients with alternative microorganism infections were performed. The SPSS v25 program for Windows was the choice for statistical analysis. Results. 71 Patients with an average age of 57 years were included, the majority being males (55%). 31% of patients were diabetic, 27% had vascular pathology, and 18.3% had a BMI greater than 35. Trimalleolar fracture was the most common in our study being 52%. 26.8% were open fractures. The microorganisms isolated were: 25% S. aureus, 22.5% E. cloacae and 22.5% polymicrobial. Accounting for polymicrobial infections, the presence of E. cloacae rises to 32%. In the univariate analysis, only significant differences were found in age (patients with E. cloacae infection were older) and the use of VAC therapy. Conclusions. In our series, higher percentages of E. cloacae infection were observed than those described in the literature. There are statistically significant differences in the variables of age and need for VAC therapy. The high incidence of E. cloacae infections suggests the vital importance of adapting antibiotic prophylaxis, ensuring the coverage of this microorganism

Introduction. The anatomic abnormalities are observed in developmental dysplasia of the hip (DDH) and it is challenging to perform the total hip arthroplasty (THA) for some DDH patients. If acetabular cup was placed at the original acetabular position in patients with high hip dislocation, it may be difficult to perform reduction of hip prosthesis because of soft tissue contracture. The procedures resolving this problem were to use femoral shortening osteotomy, or to place the acetabular cup at a higher cup position than the original hip center. Femoral shortening osteotomy has some concerns about its complicated procedure, time consuming, and risk of non-union. Conversely, implantation of the acetabular cup at the higher cup position may eliminate these shortcomings and this procedure is considered to be preferred if possible. However, the criteria of cases without femoral shortening osteotomy are not clear. In this study, we retrospectively analysed the clinical outcomes of patients performed THAs for high hip dislocation, and clarified the adaptation of THA with or without femoral shortening osteotomy. Methods. We included a total of 65 hip joints from 57 patients who underwent primary THA using Modulus stem for high hip dislocation from November 2007 to December 2015 at our institution. The mean follow up period was 5.2 years (2 – 10 years). The mean age at surgery was 65.4 years (Table 1). Thirty seven hips were classified as Crowe III, and twenty eight hips as Crowe IV based on Crowe classification. We classified patients into two groups based on the use of femoral osteotomy. Then, we compared the surgical time, blood loss, Japanese Orthopaedic Association (JOA) Score as clinical outcomes, preoperative position of the greater trochanter, the cup position, and complications between two groups. The position of the greater trochanter was measured the height of the tip of greater trochanter from the inter teardrop line. The cup center position was assessed by measuring the distance between the cup center and ipsilateral tear drop. Receiver operating characteristic (ROC) curves were plotted for deciding the cut-off value for the height of the greater trochanter. The cut-off value presented the maximum sensitivity and specificity was determined. Results and Discussion. Fifty three THAs were operated without femoral shortening osteotomy, and twelve THAs were performed with femoral shortening osteotomy. The surgical time was significantly longer in the osteotomy group than the non-osteotomy group. The mean height of the tip of the greater trochanter were 53.2±11.4mm in the non-osteotomy group and 92.2±19.7 mm in the osteotomy group (Table 2). The cut-off value of the height of greater trochanter evaluated from the ROC curve analysis was 69.5mm (Fig.1). There were no significant differences in clinical score between two groups. More ratio of revisions and fractures were observed in the osteotomy group with significant differences. Conclusion. There were significant differences in postoperative complications in osteotomy group compare to non-osteotomy group. In cases with a greater trochanter tip height of 69.5 mm or less, it may be considered to avoid femoral shortening osteotomy

Aim

Deadspace is the tissue and bony defect in a surgical wound after closure. This space is presumably poorly perfused favouring bacterial proliferation and biofilm formation. In arthroplasty surgery, an obligate deadspace surrounding the prosthesis is introduced and deadspace management, in combination with obtaining therapeutic prophylactic antibiotic concentrations, is important for limiting the risk of acquiring a periprosthetic joint infection (PJI). This study aimed to investigate cefuroxime distribution to an orthopaedic surgical deadspace in comparison with plasma and bone concentrations during two dosing intervals (8 h × 2).

High tibial osteotomy is an efficient treatment for medial compartment osteoarthritis of the knee; its used for middle aged patients with high activity levels and can delay the need for total arthroplasty. The results of total knee arthroplasty after failed high tibial osteotomy are controversies; several authors reported inferior outcomes, but others have concluded that tibial osteotomy doesn't bias following total arthroplasty. The aim of this study was to evaluate the results of failed high tibial osteotomy subsequently converted to total knee arthroplasty and compare the results to group of patients underwere primary arthroplasty; the authors evaluate some of technical problems that a previous high tibial osteotomy can generate, like scar tissue, patellar tendon shortening and changes of proximal tibial anatomy. Methods. 50 total knee arthroplasty performed after a previous closed wedge osteotomy were matched with 50 patients operated with a primary knee prosthesis for osteoarthritis. The time from a proximal tibial osteotomy to a prosthesis operation was in mean eight years. Results. the Knee Society clinical and radiographic score system and W.O.M.A.C. evaluation were used to evaluate knees before surgery and at each follow up (average 5 years). At an average of five years follow up, the clinical results of total knee arthroplasty after high tibial osteotomy were similar to those of primary knee prosthesis. Discussion. in our study revision of failed proximal tibial osteotomy appears to have more technical difficulties but with overall outcomes that remain comparable at results after primary total knee arthroplasty, so tibial osteotomy is considered a valid option in younger and very active patients with unicompartmental arthritis

The development of the High Reliability Organization focused on safety in organizations such as nuclear power plants, to avoid catastrophes in an environment where accidents might be expected due to risk factors and complexity. (Figure 1) The Agency for Healthcare Research and Quality applied High Reliability Concepts to hospitals in an effort to improve safety and quality. The Institute for Healthcare Improvement has further expanded this approach to include establishing processes to ensure highly reliable care through analysis, design or redesign, using a model for improvement, and supported by technology and the physical environment. These concepts can be applied to total knee replacement by identifying key processes, conducting regular measurement and analysis, and ensuring daily problem solving to create and maintain process reliability. The application of patient specific technology to our conventional total knee replacement procedures creates an opportunity to improve both quality and safety in total knee replacement procedures. Preoperative imaging and use of computer software allows the surgeon to develop an individual blueprint for each operative procedure. A patient specific cutting guide is fabricated for use in surgery. Intra-operative measurement of bone cuts with comparison to the planned blueprint allows correction of inaccurate bone cuts during surgery. Post operative CT scanning provides a final accurate check of limb, knee and implant alignment in 3 dimensions, with comparison to the preoperative plan. Feedback from the surgeon to the engineers involved in the planning process allows daily improvement of the guide fit, cut accuracy and accuracy of limb, knee and implant alignment for these procedures. Patient reported outcome measures such as the Oxford Knee Score or WOMAC score can be carried out preoperatively and at 6 months post op, to assess reduction of pain and functional improvements resulting from the operative procedure. Ongoing annual patient surveillance using the 12 questions on the Oxford Knee Score, one question about satisfaction, and one question asking if the patient has undergone further surgery on the operative knee, can help assess the durability of the patient outcomes and the longevity of the prosthesis. Use of patient specific cutting guides, coupled with preoperative software for planning a kinematically aligned TKA, has demonstrated improved RCT outcomes at the Phoenix VA. Figure 2 compares the distribution of WOMAC scores for kinematically aligned and mechanically aligned TKA. Individualizing the alignment for each patient has narrowed the distribution of the scores, with 87% of the kinematically aligned scores better than the median score for mechanically aligned patients. There have been additional recent preoperative, perioperative and postoperative processes and checklists designed to increase quality and safety of TKA. Medical team training for preoperative briefing and post operative debriefing, use of the AAOS new STEPPS training program, monitoring post operative results with the NSQIP/VASQIP program and database give us additional tools to improve safety and quality. Coupled with patient specific alignment technology, I believe we currently have an excellent opportunity to move toward High Reliability in total knee replacement

Background. The aim of this study is to analysis the ability of these patients, treated with MOMHR, to resume sport activities by gait analysis and clinical evaluations. Metal on metal hip resurfacing (MOMHR) is indicated to treat symptomatic hip osteoarthritis in young active patients. These patients require a high level of function and desire to resume sport activities after surgery. Study Design & Methods. 30 consecutive male patients playing high impact sports with unilateral hip osteoarthritis and normal contralateral hip were included in the study, they were treated with MOMHR by the same surgeon. No patients were lost to follow. The mean age at operation was 39.1 years (range 31 to 46). Primary diagnosis was osteoarthritis. OHS, HHS, UCLA activity score were completed at pre-operative time, six months and one year after surgery. Functionally, gait analysis was performed in all patients 6 months and one year after surgery. A stereophotogrammetric system (Smart-DX, BTS, Milano, Italy, 10 cameras, 250Hz) and two platforms (9286BA Kistler Instrumente AG, Switzerland) were used. Cluster of 4 markers were attached on the skin of each bone segment, a number of anatomical landmarks were calibrated and segment anatomical frames defined, markers were positioned by the same operator. Walking, running and squat jump were analyzed and strength and range of movement of the hips and knees were calculated. Results. At follow-up times the survival rate for the whole cohort was 100%. The mean pre-op OHS was 28.1 points (range 15.0 to 38.0), at 6 months after surgery was 44.5 points (range 44 to 48), at one year after surgery was 47.9 points (range 45 to 48). The mean pre-op HHS was 54.7 points (range 33.1 to 73.4), at 6 months after surgery was 96.7 points (range 93.4 to 100), at one year after surgery was 99.7 points (range 95.7 to 100). The mean pre-op UCLA activity score was 2.7 (range 2 to 4), at 6 months after surgery was 7.4 (range 5 to 10), at one year after surgery was 8.6 (range 7 to 10). At 6 months after surgery, patients showed a reduction of the differences between the operated and the contralateral side during walking, running and squat jumping. (p<0.01). One year after the operation there were no differences. At 3 months after surgery the mean hip flexion extension range of motion was in the normal hips 41±1.7 and in the operated hips 37.3±2.1; at 6 months after surgery the mean hip flexion extension range of motion was in the normal hips 45.4±1.8 and in the operated hips 42.0±1.7; At 1 year after surgery the hip flexion extension range of motion was in the normal hips 42.9±1.7 and in the operated hips 45.5±1.4. (p=0.001). Conclusions. Our gait analysis study shows that the biomechanical function of the operated hip is completely recovered 1 year after MOMHR operation. As a consequence sport activities can be successfully resumed. MOMHR is a good choice for young and active patients affected by hip osteoarthritis requiring a high level of activity

High tibial osteotomy (HTO) is largely conducted as an inpatient procedure, imposing the significant cost of hospital admission. Here we examine patient-related outcomes and cost benefit of altering HTO to a day-case procedure. A retrospective questionnaire was conducted with patients that underwent HTO in the one and half years prior to the change to day-case, and those in the one and half years afterwards. We considered pre-operative and post-operative KOOS scores, patient pain-scoring and whether they would, given their experience, undergo HTO as an outpatient again. Thirty-three patients were included in the trial: twenty-three inpatient admissions and ten day-cases. Average KOOS score improvement for inpatients was 24.68 and outpatients was 31.8. Outcomes such as post-operative pain and nausea/vomiting were found to be similar between groups. The outpatient group unanimously agreed that if undergoing HTO again they would desire to be treated in the outpatient setting again. Currently HTO is conducted as an inpatient procedure in the majority of institutions. We have demonstrated that patients have comparable outcomes and agree that if undergoing HTO again they would wish to do so as day-case outpatient. This represents a significant cost saving for institutions conducting HTO as well as an improvement in service

Purpose. Long-term clinical and radiographic results and survival rates were compared between closed-wedge high tibial osteotomy (HTOs) and fixed-bearing unicompartmental knee arthroplasty (UKA) in patients with similar demographics. Methods. Sixty HTOs and 50 UKAs completed between 1992 and 1998 were retrospectively reviewed. There were no significant differences in preoperative demographics. The mean follow-up period was 10.7 ±5.7 years for HTO and 12.0 ±7.1 years for UKA (n.s.). The Knee Society knee and function scores, WOMAC, and range of motion (ROM) were investigated. The mechanical axis and femorotibial angle were evaluated. Kaplan–Meier survival analysis was performed (failure: revision to TKA), and the failure modes were investigated. Results. Most of the clinical and radiographic results were not different at the last follow-up, except ROM; ROM was 135.3 ±12.3° in HTO and 126.8 ±13.3° in UKA (p=0.005). The 5-, 10-, 15-, and 20-year survival rates were 100%, 91.0%, 63.4%, and 48.3% for closed-wedge HTO, respectively, and 90.5%, 87.1%, 70.8%, and 66.4% for UKA (n.s.). The survival rate was higher than that for UKA until 12 years postoperatively but was higher in UKAs thereafter, following a remarkable decrease in HTO. The most common failure mode was degenerative osteoarthritic progression of medial compartment in HTO and femoral component loosening in UKA. Conclusions. Long-term survival did not differ significantly between closed-wedge HTO and fixed-bearing UKA in patients with similar preoperative demographics and knee conditions. The difference in postoperative ROM and failure mode should be considered when selecting a procedure

1. Introduction. Such a Total Knee Arthroplasty (TKA) that is capable of making high knee flexion has been long awaited for the Asian and Muslim people. Our research group has developed the TKA possible to attain complete deep knee flexion such as seiza sitting. Yet as seiza is peculiar to the Japanese, other strategies will be necessary for our TKA to be on the overseas market. Still it is impractical to prepare many kinds of modifications of our TKA to meet various demands from every country/region. To this end, we contrived a way to modularize the post-cum alignment of our TKA in order to facilitate the following three activities containing high knee flexion: praying for the Muslim, gardening or golfing for the Westerner, sedentary siting on a floor for the Asian. We performed simulation and experiment, such as a mathematical model analysis, FEM analysis and a cadaveric study, thereby determining the optimal combination of moduli for the above activities respectively. 2. Methods. We modularized the post-cum alignment by three parameters in three levels respectively (Fig.1). The shape of the post's sagittal section and the total shape of cum were unchanged. The three parameters for modularization were the post location which was shifted anterior and posterior by 5 mm from the neutral position, the post inclination which was inclined forward and backward by 5° from the vertical, and the radius of curvature of the post's horizontal section which was increased and decreased by 2 mm from the original value. It is crucial to decrease contact stress between the post and cum during praying for the Muslim and during gardening or golfing for the Westerner, which would be realized by choosing the optimal location and inclination of post when kneeling for the Muslim and when squatting for the Westerner respectively (Fig.2). As for the Asian, it is desirable for them to perform various kinds of sedentary sittings on a floor without difficulties, which would be facilitated by choosing the optimal radius of curvature value to increase range of rotation when the knee is in high-flexion (Fig.2). First we performed a mathematical model analysis to introduce the kinetic data during sit-to-stand activities. Then by using the above kinetic data we performed the FEM analysis to determine the contact stress between the post and cum during praying, gardening or golfing. Finally we carried out the cadaveric study to determine the range of rotation at high flexion of the knee. 3. Results and Discussion. The results of FEM analysis demonstrated that the best modular set for the activities for Muslim and Westerners were so that the post location should be shifted by 5 mm and the post inclination should not be applied (Fig.3). The results of cadaveric study demonstrated that the radius of horizontal curvature should be increased by 2mm so as to increase the range of rotation especially when the knee is in high flexion. The subjects for our future study are to verify the validities of the above results through our simulator tests