Background. The ability to kneel plays a crucial role in the daily events of nearly every individual's life, affecting occupational and domestic activities, which are, at times, closely intertwined with cultural and religious customs. The lack of literature addressing the patients concerns regarding the capacity, to which they will be able to function post-operatively, motivated us to investigate this issue further, so as to be able to more comfortably and precisely convey the answer to this question pre-operatively. Material and Methods. In this cross-sectional longitudinal study, all patients were evaluated for eligibility, with prerequisites including those having had total knee arthroplasty (TKA) secondary to a pre-operative diagnosis of osteoarthritis of the knee, from the years 2007–2010 at Poursina Trauma Center, Rasht, Iran. All procedures using a midline skin incision followed by medial parapatellar arthrotomy without re-surfacing of the patella. A PCL substituting prosthesis was chosen for implant. Demographic Data, Knee Society Score (KSS), Functional Knee Score (FKS), Visual Analog Scale (VAS), and patient kneeling ability, were all extracted and recorded, pre-operatively, 1-year post-operative, and again during final follow-up. Statistical analysis was interpreted using SPSS software version 19. Results. Of 114 cases, 69 were female (60.5%), 45 were male (39.5%), with a mean age of 67.9 ± 6.2 years (52 to 81) and mean follow-up range of 26.7 ± 2.4 months (14 to 44). VAS before surgery was 9.24 ± 0.7, which was significantly higher than those taken at 1-year follow-up, 1.82 ± 1.04, and at final follow-up, 2.01 ± 1.19. KSS and FKS values were significantly higher at both 1-year and long-term follow-up than those taken before surgery (p<0.0001). Before knee replacement 76 patients (66.7%) could not kneel, out of which 59 patients (77.6%) reported this inability because of reasons relating to the knee, while the remaining 17 patients (22.4%) reported their inability was due to non-knee associated factors. On long-term follow-up of the 59 patients whose inability to kneel was associated with issues relating to the knee, 42 patients (71.2%) found it possible to kneel again without pain or discomfort, or with mild discomfort only(see figure 1). It is clear after analyzing the data of patients who have received TKA, with regards to pre-surgical kneeling ability versus this ability months and years later, there is a statistically significant positive relationship between TKA and regaining the ability to kneel (p<0.0001). Conclusion. It seems that after total knee replacement in patients affected by osteoarthritis of the knee, the resultant decreased pain and increased function in knee flexion leads to strengthening of kneeling ability

Introduction. Fracture around the knee can lead to posttraumatic osteoarthritis (PTOA) of the knee. Malunion, malalignment, intra-articular osseous defects, retained internal fixation devices, and compromised soft tissues may affect the outcome of total knee replacement (TKR). On average, the posttraumatic patient subsets were 10.4 years younger than those for primary knee OA. Recently, there were several studies reporting the outcome of THA for posttraumatic OA hip. However, no current literature defines the comparative functional outcome between PTOA and primary OA knee. The purpose of our study was to compare the midterm outcomes of patients undergoing TKR following periarticular knee fractures/ligamentous injuries versus primary osteoarthritis (PO) of the knee. Materials and methods. Retrospective chart reviews of patients underwent TKR between 2008 and 2013 were identified. 136 patients underwent open reduction and internal fixation with plate and screws or ligament reconstruction while 716 patients were primary OA. Mean follow up time was comparable in both groups. Demographic data, medical comorbidities, WOMAC, visual analogue scale, and complications were recorded. Results. There were significantly different in age (56.5 vs 63.8 years, p<0.0001), gender (48.5% vs 63.1% of female, p=0.0014), and obese (62.3% vs 76.0%, p=0.025) between PTOA and PO groups, respectively. The PO group had higher comorbidities than PTOA group including anticoagulant usage (51% vs 30.9%, p=0.0002), number of disease ≥ 4 (69.6% vs 45.3%, p<0.0001), ASA class ≥3 (38.8% vs 21.6%, p<0.0001), and Charlson Comorbidity Index (3.6 vs 2.8, p<0.0001). The PTOA group had longer operative time (110.9 vs 100.1 minutes, p<0.0001) than PO group. Preoperatively anatomical axis of the knee was approximately valgus in PTOA but varus alignment in PO group (p<0.0001). However, postoperatively anatomical and mechanical axis was comparable in both groups. Postoperative VAS (1.8 vs 1.2, p=0.002) at 1 year follow up and pain component of WOMAC (77.8 vs 85.7, p=0.013) in PTOA group was worse than PO group, respectively. On the contrary, there was no difference in postoperative complication and readmission rate between groups. Conclusion. Total knee replacement for Post-traumatic OA was associated with poorer functional outcome compared to those for primary osteoarthritis in midterm follow up

Introduction. The deformity in osteoarthritis (OA) of the knee has been evaluated mainly in the frontal plane two dimensional X-ray using femorotibial angle. Although the presence of underlying rotational deformity in the varus knee and coexisting hip abnormality in the valgus knee have been suggested, three dimensional (3D) deformities in the varus and valgus knee were still unknown. We evaluated the 3D deformities of the varus and valgus knee using 3D bone models. Methods. Preoperative computed tomography (CT) scans of twenty seven OA knees (fifteen varus and twelve valgus) undergoing total knee arthroplasty were assessed in this study. CT scans of each patient's femur and tibia, with a 2 mm interval, obtained before surgery. We created the 3D digital model of the femur and tibia using visualization and modeling software developed in our institution. The femoral coordinate system was calculated by the 3D mechanical axis and clinical transepicondylar axis and the tibial coordinate system was calculated by the 3D mechanical axis and Akagi's line. The 3D deformities of the knee were determined by the relative position of the femorotibial coordinate system, and described by the tibial position relative to the femur. The anteversion of the femoral neck were calculated to evaluate the relationship between the valgus knee and hip region. Results. The 3D deformities of the varus knee were 12.1±5.5°varus (5.4 to 22.6°), 6.8±6.3°flexion (1.7 to 21.7°) and 6.5±6.1 °external rotation (−1.2 to 23.2°). The flexion and external rotational deformities were larger in knees with increased varus deformities. The 3D deformities of the valgus knee were 10.2±4.2°valgus (0.6 to 15.0°), 9.5±8.8°flexion (−5.2 to 23.7°) and 2.3±7.3°external rotation (−9.4 to 16.1°). Although there were no tendency about the 3D deformities in the valgus knee, the anteversion of the femoral neck in the valgus knees was 31.9°compared with 10.8°in the varus knees. Conclusion. The varus deformity in OA of the knee is associated with significant flexion and external rotational deformity. In contrast, the valgus deformity has a biomechanical background originating from the anteversion of the femoral neck

INTRODUCTION. Rotational alignment of the femoral and tibial component in total knee arthroplasty (TKA) are separately determined based on the anatomy of each bone. Popular references are the transepicondylar axis (TEA) for femoral component, and medial one-third of the tibial tubercle for the tibial component. It was reported that these references are not in accordance with each other in osteoarthritic (OA) knees and rotational mismatch could occur even when the components were accurately aligned. There has been, however, a paucity of data as for the rotational mismatch after TKA for OA knees. The purpose of this study was to evaluate the rotational mismatch between the femoral and tibial component after TKA for OA knees. SUBJECTS & METHODS. Eighty-four knees which underwent primary TKA for the varus osteoarthritis of the knee were analyzed. Those knees were chosen by the retrospective confirmation of the precise rotational alignments of both femoral and tibial components by postoperative computed tomography (with ±3 degrees to the targeted reference lines described below). The femoral reference line was the surgical epicondylar axis and the tibial reference line was Akagi's line; a line connecting the midpoint of the tibial insertion of the posterior cruciate ligament and the medial border of patellar tendon. Intraoperative, dynamic evaluations of the rotational mismatch between femoral and tibial components was performed with a special device attached to the mobile-bearing trials at full extension and in neutral, passive external rotation and passive internal rotation. RESULTS. The average rotational mismatch (in neutral position) was 4.3 ± 4.1º internal rotation of the tibial component relative to the femoral component. There was a wide range of variation from 11ºinternal rotation to 6ºexternal rotation of the tibial components. The average rotational allowance of the mobile mechanism (Between passive Internal & external rotation) was13.8 ± 5.4º (range, 6 to 30°). Neutral position was located approximately in the center of rotational allowance and 17 knees were not correctable to neutral even in the presence of mobile mechanism. DISCUSSION AND CONCLUSION. It was demonstrated that rotational mismatch between femoral and tibial components exists in extension even when both components aligned to the anatomical reference correctly. The rotational allowance of the mobile mechanism was approximately 14º and has enough tolerance to forgive the rotational mismatch to the both direction. However, 20% of the knee were not correctable to neutral rotation in the presence of mobile mechanism and operating surgeons should be aware of this fact especially when fixed and rotational motion guided knee (e.g. medial pivot knee)

Introduction. Wolff's Law proposes that trabecular bone adapts in response to mechanical loading and that trabeculae align with the trajectory of predominant loads. The current study is aimed to investigate trabecular orientation in the tibia in patients with osteoarthritis of the knee. Consistent with Wolff's Law, it was hypothesised that orientation would reflect the mechanical loading of the joint and hence that there would be a correlation between the trabecular orientation and the mechanical axis of the lower limb. Methods. 51 anonymised radiographs from patients with osteoarthritis were analysed using ImageJ (National Institute of Health). Each patient had both a standard anteroposterior radiograph of the knee and a long leg view taken while weight bearing. For each anteroposterior radiograph, the angle of the femoral shaft and tibial shaft were measured. The femoral shaft – tibial shaft (FS -TS) angle was then calculated as the difference between the two, as described by Sheehy et al. (2011). A medial rectangle was selected with the top, bottom, medial and lateral borders being the sclerotic bone, the growth line, the bone edge and the centre of the medial tibial spine. Corresponding measurements were done on the lateral side. Trabecular orientation of both areas was measured using OrientationJ (an ImageJ plugin). In all cases the medial and lateral orientation angles were expressed relative to the angle of the tibial shaft. The mechanical axis of the lower limb was measured from the full length radiographs by calculating the angle formed by the femoral and tibial axes, as described by Goker and Block. All measurements were done independently by two observers, SAS and SL. Results. Except where indicated, the results are based on analysis of 51 radiographs. Inter-tester analysis indicated excellent reliability (ICC = 0.99) for the mechanical axis measurement and preliminary inter-tester analysis (based on 25 radiographs) indicated good reliability for the orientation measurements (ICC = 0.76). The FS-TS angle calculated from the anteroposterior radiographs was significantly correlated with the mechanical axis calculated from the full-leg views (r = 0.96, p < 0.01), with an average offset of 5.7°, which is consistent with previous research. There was a significant correlation between the lateral trabecular orientation and both the FS-TS angle measured from the anteroposterior radiographs (r = −0.48, p < 0.01) (Figure) and the mechanical axis measured from the long leg views (r = −0.39, p < 0.01). There was also a significant correlation between the medial trabecular orientation and the FS-TS angle (r = 0.35, p = 0.01). Discussion. There were significant correlations between leg alignment (both the mechanical axis and the FS − TS angle) and trabecular orientation in the human tibia. These findings were consistent with Wolff's Law, which proposes that trabecular bone adapts in response to mechanical loading. To the best of our knowledge, the current study is the first to investigate in vivo trabecular orientation in the human tibia and to establish a correlation with the mechanical axis of the lower limb. The findings also suggest that inspection of the trabecular orientation might provide valuable information on leg alignment and mechanical loading prior to surgery

INTRODUCTION:. It has been reported that rotational deformity is present in varus osteoarthritis (OA) of the knee and the tibia rotates externally as the varus deformity progresses. Although many studies addressed the rotational alignment of the femoral and tibial component in total knee arthroplasty (TKA), the pre-and postoperative changes of the rotational alignment in varus OA knee has not been evaluated. The purpose of this study was to quantitatively analyze the alteration of rotational deformity after TKA for the varus OA knee. METHODS:. Between July 2011 and December 2012, 157 patients (159 knees) with primary varus OA knee undergoing TKA were included. A mobile-bearing, posterior stabilized knee prosthesis was implanted with cement in all patients. Rotational deformities were evaluated with computed tomography (CT) before and after the operation. On the selected CT slices, the relative rotational position of the femur and tibia was quantified as an angle between the line perpendicular to the surgical epicondylar axis of the femur and the line connecting the tibial tubercle tip and the geometric center of the tibia. The knees were divided into three groups according to the preoperative varus deformity (Group I; 0–8° varus, n = 78, Group II; 9–17 ° varus, n = 71 and Group III; 18 ° or greater varus, n = 10) and the difference among the groups were statistically analyzed. RESULTS:. Preoperatively, the average rotational deformity was 6.4 ± 0.9 ° (mean ± SE) external rotation of the tibia relative to the femur. This was significantly corrected to 0.9 ± 0.6 ° external rotation of tibia postoperatively (p < 0.05). The amount of preoperative rotational deformities were not significantly different among the groups (Group I; 6.6 ± 0.9 ° e.r.(external rotation of tibia), Group II; 4.3 ± 1.8 ° e.r., Group III; 5.7 ± 4.1 ° e.r.). Although the rotational deformity wasã��corrected to almost neutral in Group I and II (1.1 ± 0.4 ° e.r. and 1.4 ± 0.9 ° e.r. respectively), there was a tendency with postoperative internal rotation of tibia in Group III (4.2 ± 2.4 ° internal rotation of tibia, p = 0.10). DISCUSSION AND CONCLUSION:. This study has demonstrated that rotational deformity in varus OA knee is significantly corrected after TKA. The knees with less preoperative varus deformity are more likely to be corrected to neutral but substantial rotational mismatch (internal rotation of the tibia) remains in the knees with severe varus deformity. This might be related to the amount of the medial soft tissue release required to obtain correct limb alignment. The surgeons who perform TKA should be aware of the information and carefully check the relative position of the tibial and femoral components especially in the knees with severe varus deformity

The Osteoarthritis Hip and Knee Service (OAHKS) was introduced in 2006 and the aim of this service was to ensure early assessment and monitoring, optimise non-operative and pre-operative management, and ensure equitable access to surgical treatment. Patients were prioritised and monitored for disease deterioration using the Multi-Attribute Arthritis Prioritisation Tool (MAPT). All patients who were referred for assessment by the OAHKS between December 2006 and April 2009 were identified. Data was collected from the OAHKS computer database, hospital patient information computer system and the Department of Health databases. Scores were identified for patients who underwent joint replacement surgery (JRS) following pre-operative MAPT. Demographic and clinical data was collected prospectively and statistically analysed. Demographic data included sex, age and ethnicity. Patient clinical data included referral source and time to initial OAHKS appointment, BMI, co-morbidities, MAPT scores, referrals to other healthcare professionals and outcome of OAHKS appointment. In total, 768 patients (296 males and 472 females) were referred to OAHKS between December 2006 and April 2009. Patients ranged in age from 20 to 94 years with a mean age of 68.22 years at initial review. Patients referred were from 20 different ethnic backgrounds. The median time to initial appointment was 80.5 days (IQR 36.5-99 days). There were 656 (85.4%) patients referred from their GP and 89 referrals were from other sources. Eighty-nine per cent of patients (n=686) were screened for co- morbidities. Of these patients, 58% had hypertension, 20.8% had diabetes mellitus, 19.3% had ischaemic heart disease, and 19.8% had a psychosocial illness. The mean body mass index (BMI) was 32.71 (median 32.01). Only 42.3% patients had some form of conservative management modality prior to attending OAHKS. A total of 1061 referrals to other healthcare professionals were made. Physiotherapy (48.6%), hydrotherapy (40%) and dietician (16.1%) were the most common referrals. Referrals to the orthopaedic surgeon accounted for 15.7% total referrals. MAPT scores increased in 229 patients, decreased in 306 patients and were unchanged in 25 patients. From December 2006–March 2009, 269 patients had MAPT scoring assessment pre-operatively. Of those patients who had surgery 52% had TKR, 40.5% THR, 5.5% UKR and 1.85% hip resurfacing. The OAHKS has enabled patients with osteoarthritis to be rapidly assessed leading to a reduction in outpatient waiting times. Patients suitable for JRS are prioritised according to clinical need and MAPT scores. Thus, patients with greatest clinical need have received surgery much sooner than previously

Integrated Regional Orthopaedic (MSK) Assessment clinics (ROAC) are now mandated in many provinces for the assessment and triage of patients referred for total joint arthroplasty (TJA). Their introduction underscores the lack of means for Primary Care Physicians (PCP) to appropriately refer patients for surgical consideration. Thus, problems arise when patients who are clear candidates for surgery are subject to a significant extra step in the care pathway by attending a ROAC while those who have insufficient problems are also seen, contributing to costs and crowding the access portal. We postulated that a patient reported outcome measure, decision aid combined with a validated grading of a weight bearing knee X-ray would provide an inexpensive yet effective tool to significantly improve the referral process for Knee OA (compared with the current mechanism).

To date we have enrolled two hundred and forty-five consenting patients to the study, all referred by their PCP to the ROAC with a diagnosis of symptomatic Knee Osteoarthritis. All patients were evaluated as per the current ROAC protocol which included a medical history, physical examination and an X-ray (standing AP, lateral and patella-femoral skyline). Prior to the visit, subjects were sent a copy of a patient decision aid, Oxford Knee Score (OKS) and requested to answer whether their current clinical status described as Patient Acceptable Symptom State (PASS2) was acceptable. All radiographs were analyzed and scored for OA severity using the validated grading from 0 – 13.

Of the 245 cases, 200 completed OKS and PASS2 uestionnaires and had standing X-rays for evaluation (only 120 completed the decision aid and these were left out of this report). Of the 200 included cases, 104 were referred from the ROAC to see a surgeon. In analysis, we found that a self-reported PASS 2 answer NO and an AP X-ray graded at 6 or above predicted over 75% of those patients that were referred. This represents a 3.4 greater likelihood of referral using this simple analysis. The OKS did not modify this prediction.

Thus, use of a validated grading of a standing AP X-ray along with a response, ‘readiness for surgery’ indicated 75% of patients appropriate for surgical consideration. Patients with less severe gradings are likely being unnecessarily referred to ROAC leading to overuse of scarce resources, crowding the access and adding to costs, others, who score higher, are being needlessly delayed. The ability to discreetly screen for the best possible candidates should be a continued focus of ROAC and will lead to improved use of expensive resources, overall patient care and satisfaction and the provision of tools to the PCP for appropriate referral.

Aim. To compare the clinical effectiveness, functional outcome and patient satisfaction following intra articular injection with Synvisc. ¯. and Hyalgan. ¯. in patients with osteoarthritis (OA) of the knee. Methods. 348 consecutive patients were randomised into two groups to receive either Hylan G-F 20 -Synvisc (n= 181) or Sodium Hyaluronate -Hyalgan (n=167). All patients were prospectively reviewed by independent assessors blinded for the treatment. Knee pain on a VAS were recorded. The functional outcome was assessed using Tegner, UCLA, Oxford knee score and EuroQol-5D scores. VAS was used to quantify patient satisfaction. Mean follow-up was 12 months. Results. Mean age 66.7 yrs. Patients predominantly had grade III OA. Knee pain improved from 6.7 to 3.2 by 6 weeks (p=0.02) and was sustained until 12 months (3.7, p=0.04) with Synvisc. In the Hyalgan group, pain improved from 6.6 to 5.7 at 6 weeks (p>0.05) and to 4.1 at 3 months (p=0.04) but was sustained only until 6 months (5.9, p>0.05). Similarly, the Tegner, UCLA and Oxford knee scores were significantly better in the Synvisc group at 6 weeks (p=0.02) and 6 months (p=0.03) and 12 months (p=0.04). EQ-5D description scores were higher in the Synvisc group at 6 months (p=0.03) and 1 year (p=0.04). There was local increase in knee pain in one patient (Synvisc), which settled by 4 weeks. Patient compliance was 99.2% in the Synvisc group as compared to 92.2% in the Hyalgan. Treatment cost was 23% more in the Hyalgan group. Conclusion. Although both treatments offered significant pain reduction, it was earlier and sustained for a longer period in patients with Synvisc. Patients treated with Synvisc have demonstrated an early increase in activity levels. Local reaction of pseudo sepsis was observed with Synvisc in one patient. Total treatment cost, both for patient and hospital, is higher with Hyalgan

Purpose

To update current surgical management of knee osteoarthritis.

A prospective cohort study was undertaken to assess the success of Ossur Unloader knee brace as non-operative management of isolated medial compartment osteoarthritis.

We recruited 12 volunteers (14 knees, mean age 63) with isolated medial compartment arthritis. They were clinically assessed, demographic data and Oxford knee scores were collected before the use of the braces. At 6 months, patient satisfaction, change in symptoms and repeat Oxford scores were noted.

Improvement was noted in 5 patients (6 knees, 42%) whose mean BMI was 29. They gained confidence, knee stability and pain relief. Their mean Oxford score had improved from 28 to 41.

Bracing was unsuccessful in 7 patients (8 knees, 58%) whose mean BMI was 33. These patients were disappointed and had discontinued its regular use. Their mean Oxford score only improved from 21 to 23.

As yet no patient has undergone a knee Arthroplasty. Comparative weight bearing radiographs with and without brace reveal no change in the weight bearing alignment. 42% of the patients with a mean baseline Oxford score of above 25 and a mean BMI of below 30 responded favourably. The main causes of failure were lack of improvement in symptoms, discomfort, skin irritation and poor patient compliance.

Tibial shaft fractures co-existing with osteoarthritis can increase the challenges for the orthopedic surgeon. The novel Londhe-Shah technique manages both the problems using one-stage total knee arthroplasty with a long stemmed tibial component which has a good diaphyseal fit. Three osteoarthritis patients with fractures of tibial shaft were treated with this technique and were followed up at 6-weeks, 12-weeks and 1-year (figure 1–3). A complete union of the fractured segment was achieved at follow-up without any adverse events such as infection, damage to the implant, and soft-tissue injury during and after surgery. The American Knee Society Score (AKSS) improved and WOMAC pain and stiffness scores reduced at follow-ups suggesting excellent improvement in functionality and patient satisfaction. One-stage TKR with a long-stem extension of the tibial component to bypass the fracture site mends and stabilises the fracture along with the adverse biomechanics at the fracture site while also correcting the arthritis. The single stage procedure allows early ambulation in six weeks.

For any figures or tables, please contact the authors directly.

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).

Introduction

The management of degenerative arthritis of the knee in the younger, active patient presents a challenge to the orthopaedic surgeon. Surgical treatment options include: high tibial osteotomy (HTO), unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). The aim of this study was to examine the long-term survival of closing wedge HTO in a large series of patients up to 19 years after surgery.

Total Knee Arthroplasty (TKA) is a successful treatment for end stage osteoarthritis of the knee joint. However, post-operative pain can lead to patient dissatisfaction and poorer outcomes. Cooled radiofrequency nerve ablation (CRNA) has reportedly been effective at treating pain osteoarthritic knee pain by targeting the periarticular nerves of the knee. We undertook a prospective, controlled pilot study to determine if CRNA provides effective post-operative analgesia when utilised intra-operatively during total knee arthroplasty. Participants were recruited from January 2019 to February 2020. Those meeting inclusion criteria underwent TKA with intraoperative CRNA to 6 target sites prior to the cementing of implants. The primary outcomes were pain scores and opiate usage in the first 4 days post-operatively, then weekly up to 6 weeks. A total of 62 patients were screened and allocated sequentially; 18 were recruited to the control group and 12 recruited to the study group. The two groups did not have any significant difference in demographics. There were no clinically significant differences between the two groups in terms of pain scores nor opiate usage. There were complications as a result of the intervention. This study demonstrated no benefit of using intraoperative CRNA for improving post-operative pain scores or reducing opiate use after TKA

Introduction. The first VRAS TKA was performed in New Zealand in November 2020 using a Patient Specific Balanced Technique whereby VRAS enables very accurate collection of the bony anatomy and soft tissue envelope of the knee to plan and execute the optimal positioning for a balanced TKA. Method. The first 45 VRAS patients with idiopathic osteoarthritis of the knee was compared with 45 sequential patients who underwent the same TKA surgical technique using Brainlab 3 which the author has used exclusively in over 1500 patients. One and two year outcome data will be presented. Results. One year outcome dataVely Brainlab Significance Oxford 43.4 40.5 P=0.01 WOMAC 8.4 14.1P=0.02 Forgotten Joint Score 72.2 58.3 P=0.01 KOOS ADL91.3 85.8 P=0.04 Normal 83.3 74.2P =0.048 Activity Pain 8.6 18.4 P=0.009 ROM 127 124 P=0.01 Patient Satisfaction 98% 95% P=0.62 Operation again 100% 91% P=0.055 The two year data will be available for the ASM Conclusion: The one year outcome data shows a significantly better Oxford, WOMAC, Forgotten Joint score, KOOS ADL, Normal score and ROM scores and the activity pain is less compared to the authors extensive experience with Brainlab 3

Objective. Open-wedge high tibial osteotomy (OWHTO) involves performing a corrective osteotomy of the proximal tibia and removing a wedge of bone to correct varus alignment. Although previous studies have investigated changes in leg length before and after OWHTO using X-rays, none has evaluated three-dimensional (3D) leg length changes after OWHTO. We therefore used 3D preoperative planning software to evaluate changes in leg length after OWHTO in three dimensions. Methods. The study subjects were 55 knees of 46 patients (10 men and 36 women of mean age 69.9 years) with medial osteoarthritis of the knee or osteonecrosis of the medial femoral condyle with a femorotibial angle of >185º and restricted range of motion (extension <–10º, flexion <130º), excluding those also suffering from patellofemoral arthritis or lateral osteoarthritis of the knee. OWHTO was simulated from computed tomography scans of the whole leg using ZedHTO 3D preoperative planning software. We analyzed the hip-knee-ankle angle (HKA), flexion contracture angle (FCA), mechanical medial proximal tibial angle (mMPTA), angle of correction, wedge length, 3D tibial length, 3D leg length, and 3D increase in leg length before and after OWHTO. We also performed univariate and multivariate analysis of factors affecting the change in leg length (preoperative and postoperative H-K-A angle, wedge length, and correction angle). Results. Mean HKA increased significantly from −4.7º ± 2.7º to 3.5º ± 1.3º, as did mean mMPTA from 83.7º ± 3.3º to 92.5º ± 3.0º (p <0.01). Mean FCA was 4.7º ± 3.6° preoperatively and 4.8º ± 3.3º postoperatively, a difference that was not significant (p = 0.725). The mean correction angle was 9.1º ± 2.8º and the mean wedge length was 9.4º ± 3.2º mm. Mean tibial length increased significantly by 4.7 ± 2.3 mm (p <0.01), and mean leg length by 5.6 ± 2.8 mm (p <0.01). The change in leg length was strongly correlated with wedge length (R = 0.846, adjusted R. 2. = 0.711, p <0.01). Discussion and Conclusion. Mean 3D leg length after OWHTO increased significantly by 5.4 ± 3.1 mm. A difference in leg length of >5 mm is believed to affect back pain and gait abnormalities, and changes in leg length must therefore be taken into consideration. The 3D dimensional change in leg length was strongly correlated with wedge length, and could be predicted by the formula (change in leg length in mm) = [(wedge length in mm) ×0.75) − 1.5]. For any figures or tables, please contact authors directly

Treatment of osteoarthritis of the knee remains a challenging problem since the evolution of the disease may be different in each compartment of the knee, as well as the state of the ligaments. Total knee arthroplasty may provide a reliable long-lasting option but do not preserve the bone stock. In another hand, compartmental arthroplasty is a bone and ligament sparing solution to manage limited osteoarthritis of the knee affecting the medial, lateral or the patello-femoral compartment.1, 2, 3. Patient's selection and surgical indication are based on the physical examination and on the radiological analysis including full-length x-rays and stress x-rays. Clinical experience has shown the need for high flexion in patients who have both high flexibility and a desire to perform deep flexion. Additionally the shape differences related to anatomy or the patient expectations after the surgery may also affect the surgeon decision. 4. The limited incision into the extensor mechanism allows a quicker recovery which represents a functional improvement for the patient additionally to the cosmetic result. A dedicated physiotherapy starting on the following day allowing weight bearing exercises protected by crutches and focusing on early mobilization and range of motion combined to a multimodal pain management approach is critical despite the type of individualized solution chosen for the patient knee. 5. Since bony landmarks may be different form a patient to another one as well as anatomical shapes, several tools have been developed in order to provide the surgeons an assisted tool during the surgery adapted to each knee, this include navigation, patient specific instrumentation and robotic surgery

The iASSIST system is a portable, accelerometer base with electronic navigation used for total knee arthroplasty (TKA) which guides the surgeon to align and validate bone resection during the surgical procedure. The purpose of this study was to compare the radiological outcome between accelerometer base iASSIST system and the conventional system. Method. A prospective study between two group of 36 patients (50 TKA) of primary osteoarthritis of the knee who underwent TKA using iASSIST ™ or conventional method (25 TKA in each group) from January 2018 to December 2019. A single surgeon performs all operations with the same instrumentation and same surgical approach. Pre-operative and postoperative management protocol are same for both groups. All patients had standardized scanogram (full leg radiogram) performed post operatively to determine mechanical axis of lower limb, femoral and tibial component alignment. Result. There was no significant difference between the 2 groups for Age, Gender, Body mass index, Laterality and Preoperative mechanical axis(p>0.05). There was no difference in proportion of outliers for mechanical axis (p=0.91), Coronal femoral component alignment angle (p=0.08), Coronal tibial component alignment angle (p=1.0). The mean duration of surgery, postoperative drop in Hb, number of blood transfusion didn't show significant difference between 2 groups (p>0.05). Conclusion. Our study concludes that despite being a useful guidance tool during TKA, iASSIST does not show any difference in limb alignment (mechanical axis), Tibial and femoral component alignment when compared with the conventional method

Distal femoral varus osteotomy is a procedure intended to relieve pain, correct valgus deformity, and delay or possibly prevent the progression of lateral compartment osteoarthritis in the knee. It is indicated in patients who are considered too young or are too active to be considered candidates for total knee arthroplasty. It also allows protection of the lateral compartment in cases of meniscal or cartilage allograft. In patients who are a good candidate for total knee replacement, TKR is the procedure of choice. A sloping joint line requires that the correction be performed above the knee. Several methods of distal femoral varus osteotomy have been proposed. These include a medial closing wedge, a lateral opening wedge, and a dome osteotomy. In the author's experience, the medial closing wedge has proven reliable. This technique uses a 90-degree blade plate, and does not require any angle measurements during surgery. Fixation is secure, allowing early motion. Healing proceeds rapidly in the metaphyseal bone, and non-unions have not occurred. The desired final alignment was zero degrees, which was reliably achieved using this method. Medium to long-term results are generally satisfactory. When conversion to total knee replacement is required, standard components may generally be used, and function was not compromised by the prior osteotomy. Distal femoral varus osteotomy is a successful procedure for lateral compartment osteoarthritis in a valgus knee. It is indicated in patients who are too young or active for total knee arthroplasty, and provides an excellent functional and cosmetic result