Knee Society Function Research Articles

Effectiveness of Periarticular Pin Tracker Placement Through a Single Main Incision in Robotic-Assisted Total Knee Arthroplasty: Technical Note and Short-Term Results.

Background and Objectives: Robotic-assisted total knee arthroplasty (TKA) is gaining popularity worldwide, leading to a potential increase in the number of pin tracker-related complications. This study determined the effectiveness of periarticular pin tracker placement in the distal femur and proximal tibia through a single main incision during robotic-assisted TKA over a minimum follow-up period of 6 months. Materials and Methods: A consecutive series of 149 TKAs was performed in 108 patients using the triathlon posterior-stabilized total knee prosthesis with a robotic-assisted system at our hospital from December 2023 to February 2024. Clinical outcomes and complications associated with pin tracker sites, including pin-site infection, neurovascular injury, hematoma, soft-tissue morbidity, and pin-site fracture, were assessed. Results: The mean Knee Society knee score improved from 42.5 preoperatively to 76.3 points at the final follow-up, whereas the mean Knee Society function score improved from 43.1 preoperatively to 78.1 points at the final follow-up (both p < 0.05). No patient experienced any minor or major complications related to the use of pin trackers in the distal femur and proximal tibia. Conclusions: This periarticular technique that uses pin trackers in the distal femur and proximal tibia through a single main incision could be a useful option for orthopedic surgeons while performing robotic-assisted TKA.

Mid-term outcomes of medial metal backed and all-polyethylene unicompartmental knee arthroplasty in obese patients: a retrospective propensity-matched analysis

BackgroundThis retrospective study compares the outcomes of unicompartmental medial fixed-bearing knee arthroplasty (mUKA), involving a cemented metal-backed (MB) or an all-polyethylene (AP) tibial component, performed in obese patients with a body mass index (BMI) > 30 with a follow-up of at least 5 years.MethodsThe institutional database was mined for primary mUKAs involving an MB or an AP tibial component (MB-UKA and AP-UKA groups, respectively) performed from January 2015 to August 2019. Patient demographics and patient-reported outcome measures (PROMs) were compared and a propensity score matching (PSM) analysis (1:1) using multiple variables was conducted.ResultsPSM analysis yielded 37 pairs of obese MB-UKA and AP-UKA patients. At 5 years, the Knee Society Function Score (KSFS) was 75.1 ± 10.6 in MB-UKA and 79.4 ± 9.1 in AP-UKA patients (p = 0.029), and the Oxford Knee Score (OKS) was 38.1 ± 4.4 in MB-UKA and 40.6 ± 5.7 in AP-UKA patients (p = 0.011).ConclusionAt five-year follow-up, in a matched group of obese MB-UKA and AP-UKA patients, the AP-UKA group achieved better KSFSs and OKSs. Both the AP and the MB tibial components were able to bring about a significant improvement of the most widely used PROMs.

Clinical outcomes of primary total knee arthroplasty in non-syphilitic neuroarthropathy of the knee.

Total knee arthroplasty (TKA) in syphilitic neuroarthropathy using earlier implant designs was associated with poorer outcomes. Literature on TKA for non-syphilitic neuroarthropathy using modern contemporary prosthesis is scarce. We aim to analyse the clinical and radiological outcomes of TKA in neuropathic joints. A final cohort of 17 patients (21 knees) with the diagnosis of neuropathic joint undergoing primary TKA between January 2013 to January 2019 were included in the study. The preoperative ambulatory status, range of motion, type of prosthesis, level of constraint and any augmentation used were retrieved from medical records. Radiological evaluation includes Koshino's staging, the magnitude of deformity defined by the Hip-Knee-Ankle (HKA) angle, and any progressive loosening. Pre and postoperative functional scores were obtained by the Knee Society (KSS) and Knee Society Functional Score (KSS-F). Any complications or reoperation were noted till the final follow-up. Preoperative and follow-up functional scores, HKA and range of motion were compared using the paired Samples test. The mean follow-up was 40.2 months (range, 15 to 75 months). Preoperatively, according to the Koshino staging, five knees were in stage 3 (23.8%). The mean HKA angle in valgus knees was 23.60 (range, 11.10 to 42.50) and for the varus knees was 19.30 (range, 4.90 to 39.60). The prosthesis used were posterior stabilized in 7 knees (33.3%), varus-valgus constrained in five knees (23.8%) and a rotating hinge was required in nine knees (42.8%). Metaphyseal sleeves were used along with hinge prosthesis in six knees (28.6%). The mean arc of motion improved from 102.4 ± 22.7 degrees to 105.7 ± 15.5 degrees postoperatively (p = 0.27). The knee society and knee society functional scores improved from 23.3 ± 9.3 and 28.3 ± 12.2 preoperatively to 81.1 ± 5.4 and 80.4 ± 8.5 during the follow up respectively (p < 0.001). There were no progressive radiolucent lines in any knees at the final follow-up. One patient had intraoperative bony medial collateral ligament injury, one patient had deep vein thrombosis after five days from the index surgery and another had postoperative periprosthetic tibial shaft fracture. According to our study, the clinical outcomes of TKA for neuroarthropathy show significant improvement with the diagnosis of non-syphilitic neuroarthropathy, utilization of modern constrained prostheses, and early rehabilitation, at medium-term follow-up. Tibial and femoral stems are preferred for equal stress distribution and to prevent early loosening.

Outcomes of total knee replacement versus unicompartmental knee arthroplasty in an enhanced recovery after surgery protocol

IntroductionUnicompartmental Knee Arthroplasty (UKA) has become popular due to faster recovery and improved range of motion. However, concerns have been made regarding increased risk of early failure. Furthermore, the use of Enhanced Recovery After Surgery (ERAS) protocols have shown to allow faster return to activities, improved satisfaction, and reduced complication rates.This study aims to compare the 6 month functional outcomes of patients undergoing Total Knee Replacement (TKR) versus UKA under the ERAS protocol. MethodsPatient characteristics and comorbidities, 30-day post-operation readmission and infection rates were analyzed. Patient reported outcomes measures namely the Knee Society Function and Knee Score (KSFS, KSKS), Oxford Knee Score (OKS) and both the Physical and Mental component of the Short-Form Health Survey (SF-36) were assessed pre-operatively and 6 months post-operatively.Univariate analysis was used to compare differences in characteristics and comorbidities between the 2 groups. Finally, a multiple linear regression was performed to compare the post-operative outcomes. ResultsUnivariate analysis showed significantly better preoperative and 6 month post-operative KSKS and SF-36 MCS in UKA patients. Multivariate analysis showed no difference in the 6 month post-operative functional outcome scores between UKA and TKR patients. No UKA patients required revision surgery while 4 TKR patients required revision surgery for infection. ConclusionUKA achieves equivalent functional outcomes at 6 months post-operatively as compared to TKR patients and has lower infection rates. UKA is a reasonable option to offer for unicompartmental knee osteoarthritis patients.

Midterm results for revision total knee arthroplasty for component malrotation

IntroductionAccurate positioning of components in total knee arthroplasty (TKA) is essential to a satisfactory outcome. Significant malrotation may lead to chronic pain, stiffness, and dysfunction. This study aims to quantify improvements in functional outcomes following revision surgery for malrotation of either one or both components in TKA versus revision for aseptic loosening. MethodsThis was a retrospective review of TKAs that matched and compared the two-year functional outcomes of the malrotation group to a functionally similar aseptic loosening group. Functional outcomes were compared between groups using Short Form (SF-12), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and Knee Society Functional Score (KSFS). Student t-tests and chi-squared or Fisher’s tests were used for statistical analysis. ResultsOf the patients revised, 24 had malrotation and 57 had aseptic loosening. A total of 16 femoral and 17 tibial components were revised for malrotation. All 16 femoral components were internally malrotated (mean –4.8 ± 4.1 degrees; range, −0.5 to −16.6). Of the tibial components, 15 were internally malrotated, (mean −9.5 ± 6.6 degrees; range, −2.2 to –23.5) and 2 were externally malrotated (mean 4.6 ± 2.1 degrees; range, 3.1 to 6.0). All functional outcome measures significantly improved comparably within both groups preoperatively to 24 months postoperatively. At 24 months, functional outcome measures were comparable between the groups and WOMAC function scores were significantly higher in the malrotation group. ConclusionRevision TKA for malrotation can yield clinically and statistically significant functional improvements, similar in magnitude to those seen following revision TKA for aseptic loosening. Level of EvidenceLevel III

Application of Autologous Bone Graft versus Non Grafting in Medial Opening Wedge High Tibial Osteotomy Less than 14 mm: A Systematic Review and Meta-Analysis

Abstract Background Unicompartmental Knee osteoarthritis KOA due to varus malalignment is increased in young active patients which occurs predominantly in the medial compartment. Aim of the Work The objective of this study to compare MOWHTOs with autologous bone graft and without bone graft (wedge space mean less than 14 mm) in treatment of unicompartmental KOA and varus malalignment of the knee to determine which is better in decision-making according to outcomes. Patients and Methods Studies that matched the inclusion criteria were included in this meta-analysis. participants with medial compartmental knee osteoarthritis and varus malalignment were shown in the investigation. The age of the participants was unrestricted. Plate as a fixation method was the only option regardless of plate type. During 2000 and 2021, a research study of internet databases (Egyptian Universities Research, Medline, PubMed, Cochran library, medical journals) was conducted. Following that, the references from the user research were examined, and specialists were approached for assistance in locating other papers. Two independent reviewers extracted data separately and cross-checked it. Results The Knee Society Knee score (KSKS) and Knee Society Function score (KSFS) are most commonly used for the assessment of the knee joint reveled that there is no statically significant difference between bone graft vs non graft. Regarding this systematic review the radiological outcomes, the clinical bone union and the full weight bearing movement, are rendering any statistical analysis meaningless. Regarding complications presented, there was a similar tendency for complication rate when compared according to grafting or non- grafting. The use of autograft accelerates radiographic healing of the osteotomy gap after OWHTO while shorten the union time but confers no advantages in terms of functional or patient elated out comes at 3 or 12 months postoperatively. Conclusion MOWHTO can be performed without a graft with less operative time and avoiding graft harvest comorbidity with similar clinical and radiological results regarding bone union and posterior tibial slope alteration and knee scores.

Comparative Analysis of Outcomes of Lateral Versus Medial Approach in the Total Knee Arthroplasty for Valgus Deformity: A Systematic Review and Meta-analysis.

Valgus knee deformity poses great challenges in total knee arthroplasty (TKA) and requires precision in balancing of soft tissue and implant component positioning. The surgical approach used for TKA has a determinantal impact on intraoperative soft tissue balancing, postoperative knee function, and complications. We executed a systematic review and meta-analysis of current literature, which included a maximum number of studies with quantitative analysis of all possible outcomes to substantiate the current evidence of the advantage of lateral versus medial approach in TKA for valgus knee deformity. We performed a meticulous primary electronic search across PubMed, Emabse, Scopus, and Cochrane Library databases, and looked for the comparative studies that evaluated the medial versus lateral approach in TKA for valgus knees. Statistical analyses were executed with RevMan-5.4.1. On the evaluation of four randomized controlled trials (RCTs), two prospective and five retrospective comparative studies, our analysis revealed a better functional outcome in terms of Knee Society Score [MD 2.24, 95% CI 0.42, 4.05; p = 0.02] with the medial approach. However, comparable results were observed for two approaches with regard to Knee Society Function [MD 0.69, 95% CI -1.77, 3.15; p = 0.58], knee flexion range of motion (ROM) [MD 3.30, 95% CI -1.34, 7.95; p = 0.16], overall complications [OR 0.60, 95% CI 0.27,1.34; p = 0.22], wound-related complications, infection, nerve injury, periprosthetic fracture, post-operative valgus, blood loss, duration of surgery, postoperative pain, and patellar tilt for TKA in valgus knee. Evidence from the currently available published data suggests that the lateral approach, compared to the medial approach in TKA for the valgus knee, does not show clear superiority.

Functional Outcome of Patients with Malignant Tumors around the Knee Treated by Modular Endoprosthesis: A Comparative Study between Patellar Resurfacing and Nonresurfacing

Abstract Background: Patellar resurfacing with knee arthroplasty has always been controversial. The literature contains data that support both resurfacing and not resurfacing the patella. However, the literature does not review a lot of studies that address the impact of patellar resurfacing on the functional outcome following resection of distal femur tumors and limb salvage using modular prosthesis. Questions/Purposes: Is patellar resurfacing better than nonresurfacing as regards functional outcome of modular prosthesis used for the treatment of tumors around the knee? Patients and Methods: Two groups of patients; both were subjected to wide excision of tumors around the knee and limb salvage using modular prosthesis. The first group underwent reconstruction with patellar resurfacing, while the second underwent reconstruction without patellar resurfacing. The age of these groups of patients ranged from 11 to 71 years. The patients were 17 males and 19 females. We evaluated patients using the musculoskeletal tumor society scoring system (MSTS), knee society final score, knee society function score, and anterior knee pain score. Results: We found that MSTS functional score, knee society final score and knee society function score, and anterior knee pain score were all better in patients who underwent patellar resurfacing compared to nonresurfacing patients. However, only the difference in anterior knee pain score was statistically significant (P = 0.030). Differences in other scores between these two groups were all statistically insignificant (P value of the MSTS difference = 0.103, P value of the knee society final score difference = 0.423, and P value of the knee society function score difference = 0.337). Conclusions: Patellar resurfacing could be helpful in decreasing anterior knee pain and the necessity to future surgeries addressing patellofemoral pain, especially in revision cases, patients with patellofemoral problems, and patients with extensor mechanism weakness and those with anterior knee pain. Since Anterior Knee Pain Scale was the only scoring system, among all scoring systems used, that confirmed a significant impact of patellar resurfacing on the outcome following resections and reconstructions; we cannot give an explicit strong recommendation favoring the routine patellar resurfacing in all cases undergoing resections and reconstructions using modular prosthesis. We recommend patellar resurfacing in older patients, based on our results, which show possible benefit of patellar resurfacing in older patients. We think that old age and the preexisting knee arthritis could be relative indications for patellar resurfacing.

High tibial osteotomy versus unicompartmental knee arthroplasty in advanced medial compartmental knee arthrosis: A comparative study with propensity score matched analysis

BackgroundIsolated knee medial compartmental osteoarthritis(MOA) can be treated with High Tibial Osteotomy (HTO) or Unicompartmental Knee Arthroplasty (UKA).This study aims to describe and compare outcomes of HTO and UKA in patients with isolated severe MOA. The authors hypothesized that similar outcomes can be achieved. MethodsData was collected prospectively of HTOs and UKAs performed between January-2016 and April-2021 by a knee surgeon. Oxford Knee Score (OKS), Knee Society Knee Score (KSKS) and Function Score (KSFS) were collected pre-operatively, six-months and two-years post-surgery. OA severity was graded on pre-operative radiograph. Medial Proximal Tibia Angle (MPTA), Lateral Distal Femoral Angle (LDFA), Joint Line Convergence Angle (JLCA) and Hip-Knee-Ankle Angle (HKAA), were measured on full-length radiograph.47 HTO and 74 UKA were included. Propensity score matching was performed, accounting for preoperative scores, age, gender and body mass index (BMI), before statistical analysis. Level of significance was set at 0.05. ResultsBoth groups were similar in age(56.42 vs 58.57, p = 0.067), BMI(29.82 vs 29.09, p = 0.484), gender distribution (p = 0.663) and laterality (p = 0.836).Pre-operatively, both groups were similar in clinical scores and lower limb alignment. On follow-up, both groups achieved similar improvements in clinical scores. However, the HTO group reported poorer extension at 6-months (7.91° vs 4.80°, p = 0.013) and 2-years (5.57° vs 3.24°, p = 0.018).Three cases of hinge fracture and six cases of implant removal occurred in the HTO group. One case of tibial fracture occurred in the UKA group. ConclusionsIn severe MOA, similar outcomes were achieved with HTO and UKA at two years.

Effectiveness and Complications of Bone Marrow Aspirate Concentrate in Patients with Knee Osteoarthritis of Kellgren-Lawrence Grades II-III.

This study aimed to identify the effectiveness and potential complications on the harvest site and knee of bone marrow aspirate concentrate (BMAC) treatment of patients with Kellgren-Lawrence (K-L) grades II-III knee osteoarthritis (OA) over a minimum follow-up period of 6 months. This study retrospectively evaluated data from 231 patients (285 knees) with knee OA treated with BMAC articular injection at a single center from August 2023 to October 2023. The inclusion criteria were a longstanding knee pain unresponsive to conservative treatments for at least 6 weeks with K-L grades II-III OA. The exclusion criteria were age of <40 years or >80 years, previous knee surgery, rheumatological or other systemic disease, malignancy, uncontrolled diabetes mellitus, or infections. Bone marrow was aspirated from the anterior iliac crest and concentrated by the single-spin centrifugation technique. The visual analog scale (VAS) pain score and Knee Society Score were used to evaluate the clinical outcomes and complications associated with harvest and injection sites were evaluated. The mean follow-up period was 7.2 months (range: 6-8 months). The pretreatment VAS pain score decreased from 4.3 to 0.4 points at the final follow-up (p < 0.05). Pretreatment Knee Society knee and function scores were improved from 86.9 to 98.1 (p < 0.05) and from 68.4 to 83.3 points (p < 0.05), respectively. A total of 15 complications (5.3%, 15/285) were observed, including 3 hematomas, 2 numbness, 2 contact dermatitis, and 1 superficial infection in the harvest site and 4 mild and moderate swelling and 3 severe swelling and pain in the injection site. BMAC is a reliable and effective treatment for patients with K-L grades II-III knee OA, but the orthopedic surgeon should consider that bleeding tendency by heparin causes severe joint swelling and pain after intra-articular knee injection.

Robotic-assisted total knee arthroplasty reduces soft-tissue releases which improves functional outcomes: A retrospective study

BackgroundThere is increasing use of Robotic-Assisted (RA) and personalized alignment techniques in total knee arthroplasty (TKA). The hypothesis of this study was that RA TKA would result in fewer soft-tissue releases, and that fewer soft-tissue releases would be associated with improved clinical outcomes. MethodsA retrospective review of an internal company registry was conducted for all primary TKAs performed from Jan 1, 2014, through a database extract date of Nov 4, 2022. These were grouped by whether there was an intentional soft-tissue release performed (STR) during the surgery or not (NSTR) and whether RA was utilized. The incidence of STR was compared between RA-TKAs and those performed with manual instrumentation. Knee Society Score (KSS) and Knee Society Function Scores (KSFS) were collected at 6 months, 1 year and 2 years. Kaplan-Meier survivorship was performed. ResultsThe incidence of STR was significantly lower for RA vs. Manual (43.81% Vs 86.62%, p < 0.0001). The TKAs with NSTR had higher KSFS compared to those with STR at 6 months (84.73 Vs. 77.51, p < 0.0001), 1 year (89.87 Vs. 83.54, p < 0.0001) and 2 years (90.09 Vs. 82.65, p < 0.0001). There was no difference in survivorship, or KSS at any time point. However, the NSTR group had improved KSS pain sub score at 2 years. ConclusionThe results of this observational, retrospective analysis found that the incidence of soft-tissue release was lower with RA-TKA. Further, regardless of if RA was used, avoiding releases was associated with improved KSFS and KSS pain scores through 2 years post-operatively.

A Simple Surgical Technique for Correction of Varus Deformity in Advanced Osteoarthritis of Knees by Medial Femoral Condylar Sliding Osteotomy-Description of Procedure and short term Outcome-A Prospective Study.

Advanced osteoarthritis of knees with varus deformity consists of attenuation of lateral structures with contracture of the posteromedial structures and formation of medial osteophytes. The conventional step-wise medial and posteromedial release with measured resection may sometimes hinder achievement of perfectly balanced flexion and extension gaps with maintenance of flexion stability, without the use of a constrained prosthesis. Medial femoral epicondylar sliding osteotomy tailors the balancing to the need of the kinematics of the native knee and precludes the use of a constrained implant. 15 patients with Ahlbäck Grades III through V osteoarthritic changes at Howrah Orthopaedic Hospital were included in a prospective cohort case series with a minimum period of follow-up being 12months. Physical examination, clinical questionnaire and radiographic evaluation were done post-operatively for objectification by functional Knee Society and Oxford Knee Scores respectively. The mean post-operative femorotibial angulation ameliorated to a value of 3.73 ± 1.58° from 18.67 ± 4.2° in the pre-operative stage. The mean overall Range of Motion of operated knee was 109.87 ± 6.86° with no residual frontal laxity and/or laxity in the coronal plane. The mean amount of resection of tibial plateau in patients with severe varus deformity was kept to a minimum, 6.56mm from the least deficient portion of the lateral condyle. There were no complications as regards component loosening and/or surgical-site infection. The main objective of balancing a severely varus-afflicted knee is to preserve as much of the Medial Collateral Ligament as possible, to retain its check rein function and not jeopardise the stability. This is ensured by distalisation and posteriorizing the medial epicondyle by an incomplete osteotomy in addition to modest tibial resection fetching a non-isometric point of knee flexion. All osteotomies united by bony union and restoration of kinematic alignment. The limitation of this study however includes the lack of long-term results, such as late instability and polyethylene wear.

Gender does not influence outcomes and complications in medial unicompartmental knee arthroplasty.

The impact of gender on the outcomes of unicompartmental knee arthroplasty (UKA) remains a topic of active discussion with limited exploration thus far. The study aims to elucidate the gender effect on clinical outcomes, complications, pre- and postoperative radiological outcomes following the implantation of a medial UKA at mid-term follow-up in a large sectionof patients. This was a single-centre, retrospective cohort study encompassing patients undergoing medial UKA between 2011 and2019. The International Knee Society (IKS) Knee and Function score, patient satisfaction, complications, revisions, pre- and postoperative radiological outcomes (coronal plane alignment, femoral and tibial component positioning, posterior tibial slope) were evaluated. Survival rate at the time of the last follow-up was also recorded. Of the 366 knees that met the inclusion criteria, 10 were lost to follow-up, accounting for a 2.7% loss. Mean follow-up was 5.2 ± 2 years [2.1-11.3]. Out of the total population, 205 patients were females (57.6%, 205/356) and 151 were males (42.4%, 151/356). Men exhibited superior pre- and postoperative IKS function scores (p = 0.017). However, no significant differences were observed between women and men regarding improvements of IKS Knee and Function scores, radiographic outcomes and implant survivorship. At a mean follow-up of 5 years, this study revealed no significant impact of gender on clinical outcomes and complications in patients undergoing medial UKA. Furthermore, no significant differences were evident in radiographic outcomes, implant positioning and knee phenotype. Level III.

Postponement of total knee arthroplasties due to pandemic causes significant deterioration on patients’ preoperative knee and quality of life scores

IntroductionElective surgeries were postponed during the COVID-19 pandemic to alleviate healthcare strains, affecting majority of elective orthopaedic surgeries such as total knee arthroplasties (TKAs). The aim of this study is to evaluate the impact on knee function and quality of life of patients who had their planned TKA postponed due to the pandemic. MethodsThis is a retrospective analysis of data collected in a tertiary hospital. Patients included were diagnosed with primary knee osteoarthritis and they were initially scheduled for primary TKA between January to April 2020 but surgery was postponed by at least 6 months from the initial operative date. 160 patients were included in this study (53 males and 107 females, mean age 68.0 ± 8.1). Patients were assessed prior to initial surgery date and assessed again, prior to the postponed surgery date. Clinical scores included Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS), Oxford Knee scores (OKS) and Short-Form 36 Physical and Mental Component Scores. (SF36 PCS and MCS). Paired T-test was performed for parametric data whereas Wilcoxon signed-rank analysis was performed for non-parametric data. ResultsComparing initial preoperative versus postponement preoperative scores, the cohort had significantly poorer KSKS (38.4 ± 15.4 and 36.5 ± 15.4, p = 0.034), SF36 PCS (34.3 ± 9.2 and 32.7 ± 8.6, p = 0.02) and OKS (34.9 ± 0.77 and 35.8 ± 8.6, p = 0.02) scores respectively. ConclusionThe postponement of elective TKAs has resulted in a significant deterioration of knee scores and physical quality of live scores of patients in a short span of 6 months. Further studies can evaluate if there are repercussions on long term TKAs outcomes. Level of evidenceRetrospective study, Level III.

Unicompartmental knee arthroplasty in obese patients, poorer survivorship at 15 years

IntroductionThe preclusion of obese patients from unicompartmental knee arthroplasty (UKA) has increasingly been challenged. This study aimed to evaluate the impact of Body Mass Index (BMI) on UKA at 15-year follow-up. Materials and methods169 unilateral UKA patients from 2003 to 2007 were followed-up prospectively for at least 15 years. 70 patients were left for analysis after accounting for patient demise, revision surgery and loss to follow-up. 48 of these patients (69%) were in the Control group (BMI <30 kg/m2) and 22 (31%) were in the Obese group (BMI ≥30 kg/m2). Patients were assessed before and after operation using the Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS), Oxford Knee Score (OKS), and Physical (PCS) and Mental (MCS) component of the Short Form 12. Survivorship analysis was also performed. ResultsObese patients went through UKA at an earlier age than the non-obese patients (54.7 ± 4.7 years compared to 59.9 ± 7.8 years, p = 0.005). At 2, 10, and 15-year follow-up, both groups achieved clinically significant improvements in outcomes. There was no significant association found between obesity and outcome using multiple linear regression. While propensity matching found PCS improvement at 2 years to be greater in obese patients, no significant association between obesity and 15-year outcome was found. All 13 patients who required revision, underwent total knee arthroplasty (TKA). The overall 15-year survivorship was 74.2% within the obese group and 92.4% within the control group. ConclusionCompared to non-obese patients, obese patients had poorer 15-year survivorship with greater odds of requiring revision surgery. However, assuming implant survival, obese patients can expect a non-inferior outcome relative to their non-obese counterparts in all patient reported outcome measures 15 years after surgery.

Use of semi-constrained total knee arthroplasty in gonarthrosis with collateral ligament insufficiency: Clinical and functional outcomes

IntroductionAchieving stability in total knee arthroplasty (TKA) is crucial for long-term implant survival. In cases of severe deformity or ligament laxity, constrained implants may be required. Traditionally, increasing constraint involved intramedullary stems. However, there are intermediary alternatives, including employing a constrained polyethylene insert without stems, thereby avoiding complications related to them. The study aims to evaluate our experience with a non-modular constrained (NMC) implant in primary TKA. Material and methodsWe conducted a retrospective review of the clinical and radiographic outcomes of 108 non-stemmed primary TKAs performed at our institution between 2013 and 2021 in patients with at least 10° deformity or 10mm ligament laxity. Data included demographics, preoperative and postoperative deformities, clinical outcomes and revision rates. ResultsA total of 103 patients (108 knees) with a mean age of 74 were followed up for a minimum of 2 years. The mean postoperative range of motion was 105°/0°. The median Oxford Knee Score, Knee Society Score and Knee Society Function Score were 43.5, 92 and 90, respectively. 17 knees had varus deformity (mean tibiofemoral angle of 2.7°), and 87 knees had excessive valgus deformity (mean tibiofemoral angle of 15.1°). The remaining 4 knees had a neutral alignment. The mean postoperative tibiofemoral angle was 6.8°. The overall revision rate was 6.5% (7 patients): 3 deep periprosthetic infections, 2 patellar dislocations, 1 stiffness and 1 aseptic loosening. ConclusionOur experience demonstrates favorable mid-term outcomes with the NMC implant, providing a safe alternative to stemmed implants in primary TKA, particularly in cases of severe deformity or ligament laxity.

Comparison of Outcomes in Obese Patients after Total Knee Arthroplasty with Neutral or Mild Varus: A Retrospective Study with 8-Year Follow-Up.

Residual varus after total knee arthroplasty (TKA) can affect functional outcomes, which may worsen in the presence of obesity. However, no studies were found to compare the outcomes of obese patients involving postoperative residual mild varus or neutral. The aim of this study was to compare postoperative complications and prosthesis survival, and functional outcomes for knees of obese patients with neutral or mild varus after TKA. We retrospectively reviewed 188 consecutive obese patients (body mass index ≥30 kg/m2) at our hospital who underwent TKA due to varus knee osteoarthritis from January 2010 to December 2015. The mechanical hip-knee-ankle axis angle was measured in all patients at admission and discharge. Knee functions were retrospectively assessed based on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, Knee Society Knee Score (KS-KS), Knee Society Function Score (KS-FS), Forgotten Joint Score (FJS), and range of motion (ROM). Continuous data were compared between knees with neutral or mild varus alignment using analysis of Student's t test or variance or the Kruskal-Wallis test as appropriate. For multiple comparisons of outcomes, we used Bonferroni-Dunn method to adjust p-values. Categorical data were compared using the chi-squared test. Of the 156 knees in 137 obese patients who completed follow-up for a mean of 8.32 ± 1.47 years, 97 knees were corrected from varus to neutral and 54 knees were kept in mild residual varus. Patients with mild varus knees had significantly WOMAC (8.25 ± 8.637 vs. 14.97 ± 14.193, p = 0.009) and better FJS (86.03 ± 15.607 vs. 70.22 ± 30.031, p = 0.002). The two types of knees did not differ significantly in KS-KS, KS-FS, or ROM. Although one patient with a neutral knee had to undergo revision surgery, there was no significant difference between two groups. For obese patients with osteoarthritis, preservation of residual varus alignment after TKA can improve functional outcomes without compromising prosthesis survival.

Severe genu varus deformity does not affect enhanced recovery after surgery total knee arthroplasty outcomes.

Enhanced recovery after surgery (ERAS) has been increasingly adopted in orthopaedic surgery. Although not an exclusion criterion, patients undergoing total knee arthroplasty (TKA) with preoperative severe varus deformity may be less likely to be enrolled for ERAS. This study aimed to compare the success of ERAS TKA between patients with severe preoperative varus deformities (≥ 15° varus) and the control group (< 15° varus to 14° valgus). Our secondary aim was to compare postoperative complications and functional outcomes between the two groups. 310 TKAs performed from August 2019 to February 2021 were analyzed with a follow-up of 6 months postoperatively. The primary outcome, ERAS TKA success, was defined as length of hospital stay of < 24h. Other parameters included 30-day postoperative complications and clinical outcomes such as the original Oxford Knee Score (OKS), the Knee Society Knee (KSKS) and Function Score (KSFS), Visual Analog Scale for Pain (VAS-P), 36-Item Short-Form Health Survey (SF-36) Physical Component Summary (PCS) and SF-36 Mental Component Summary (MCS). There were 119 patients in the severe deformity group and 191 patients in the control group. There were no significant differences in ERAS success between the severe deformity group and control group, with both groups achieving similarly high rates (> 90%) of ERAS success. There were also no differences in 30-day postoperative complications and 6-month postoperative clinical outcomes. Patients with severe preoperative varus deformity undergoing ERAS TKA achieved high ERAS success rates (> 90%). Genu varum is not a contraindication for ERAS TKA.

Minimum 19-Year Clinical Results and Patient Satisfaction After Total Knee Arthroplasty

BackgroundLong-term (minimum 19-year) outcome data on clinical results and patient satisfaction after posterior-stabilized total knee arthroplasties (TKAs) are missing in the literature. The purpose of the study was to evaluate the clinical and radiographic results as well as patient satisfaction at a mean of 21.2 years after posterior-stabilized TKAs. MethodsThis study included 756 patients (1,350 knees) who had undergone TKAs. There were 96 men and 660 women (mean age, 58 years; range, 40 to 84). The mean follow-up was 21.2 years (range, 19 to 23). At each follow-up visit, the patients were assessed radiographically and clinically. Furthermore, patient satisfaction was determined. ResultsThe Knee Society total, pain, function, and deformity scores were 42, 18, 33, and 5 points, respectively, at the final follow-up. The mean Western Ontario and McMaster Universities Arthritis Index score was 25 points at the final follow-up. With revision or aseptic loosening as the end point, the 23-year intimated survival for the implant was 96% (95% confidence interval, 91 to 100%). The overall patient satisfaction score at the final follow-up was 83.3 points (range, 81 to 86). Patient satisfaction scores with regard to pain, housework, recreation, and surgery were 84, 81, 82, and 86 points, respectively. ConclusionsThe findings of the present, mean 21-year follow-up clinical study suggest excellent results with regard to the revision rates and survivorship of the posterior-stabilized total knee implants. However, consistent with the literature, we found that about 80% of patients expressed overall satisfaction with their primary TKAs. About 8% of patients were either somewhat or very dissatisfied with the procedure.

First Italian Experience with the Oxinium Metal-Backed Fixed-Bearing Medial Journey II Unicompartmental Knee System: Promising Short-Term Outcomes of 145 Cases.

(1) Background: Unicompartmental knee arthroplasty (UKA) provides a viable alternative to total knee arthroplasty (TKA) in patients with isolated medial osteoarthritis (OA). From 2007 to 2021, 23% of all primary knee arthroplasties in Italy were UKAs. We retrospectively evaluated clinical outcomes and satisfaction in patients implanted with a new oxinium metal-backed fixed-bearing medial unicompartmental prosthesis at a 24-month follow-up. (2) Methods: From December 2020 to December 2021, 145 patients were treated by a single surgeon at a single institution using the hypoallergenic Journey II prosthesis. Clinical outcome measures included the Knee Society Knee Score (KSKS), Knee Society Function Score (KSFS), Oxford Knee Society (OKS) score, University of California Los Angeles Activity Score (UCLA), the Physical Component Summary (PCS), and the Mental Component Summary (MCS), and were calculated preoperatively and at 12 and 24 months. The Forgotten Joint Score-12 (FJS-12) was calculated at 12 and 24 months. Patient satisfaction was collected at 24 months. The scores were compared using the Friedman test. (3) Results: All clinical scores improved significantly from baseline to 24 months (p < 0.0001), except for the FJS-12, which from 12 to 24 months did not improve significantly (p = 0.041). Patient satisfaction was 9.32 ± 0.74 out of 10. No patient experienced complications or required revision surgery. (4) Conclusions: The Journey II unicompartmental prosthesis is a valuable treatment option for end-stage medial OA, improving knee function, providing pain relief, and ensuring high patient satisfaction at 24 months.