Purpose: To assess clinical and functional outcomes, complications and implant survival in lateral or medial unicompartmental knee arthroplasty (UKA) to treat femorotibial joint osteoarthritis (FTJ-OA), regardless of associated patellofemoral joint osteoarthritis (PFJ-OA) clinical symptoms or radiographic signs. Methods: Patients with or without preoperative symptoms or signs of PFJ-OA, treated with medial or lateral UKA with a minimum 1-year follow-up were included. Intraoperatively, knees were subdivided based on their PFJ-OA grade, using Outerbridge classification. Clinical and functional outcomes were analyzed using 2011 Knee Society Score (KSS). PFJ-OA was treated systematically, in a tailored, stepwise fashion according to its severity. Complication and implant survival rates were evaluated. Results: 110 UKAs were assessed; 81 (73.6%) were medial UKA. Average follow-up was 6 years (1-19.5). According to the Outerbridge classification for patellofemoral chondropathy, 22 knees (20%) were grade 2, 59 (53.6%) grade 3 and 29 (26.4%) grade 4. There were no significant differences in clinical KSS improvement and flexion contracture between Outerbridge groups (p=0.07 and p=0.37, respectively). Group 3 showed statistically significant improvement in functional KSS when compared to group 2 (p=0.04). In maximum flexion, groups 3 and 4 did significantly better than group 2 (p=0.04). Implant survival at 5, 7, 9 and 12 years was 100% (64 prostheses), 97% (31 prostheses), 93% (15 prostheses) and 89% (9 prostheses), respectively. Conclusions: Medial or lateral UKA is a safe procedure with low complication rates and favorable results regardless of PFJ-OA. Associated PFJ-OA is not a contraindication for UKA when treated systematically based on its severity.

Background: Unicondylar knee replacement (UKR) is increasingly utilized for treating isolated compartmental knee arthritis in younger patients. However, the optimal choice between medial and lateral UKR in this demographic remains uncertain.
Methods: Prospective data from a study conducted between 2010 and 2014 were analyzed to compare outcomes of medial versus lateral UKR in patients under 60 years old. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Short Form 36 (SF36) scores were collected preoperatively and postoperatively to assess functional outcomes.
Results: A total of 300 patients (67% male, 33% female) were included in the analysis. Both medial and lateral UKR demonstrated significant improvements in WOMAC and SF36 scores postoperatively (p > 0.05). There was no statistically significant difference between the two groups in terms of postoperative WOMAC and SF36 scores.
Conclusion: In patients under 60 years old, medial and lateral UKR procedures yielded comparable improvements in functional outcomes, as assessed by WOMAC and SF36 scores, with no significant difference observed between the two groups. This suggests that both medial and lateral UKR may be effective options for this age group, emphasizing the importance of individualized treatment decisions based on patient-specific factors and surgical considerations.

Background
The joint line orientation angle (JLOA) has been reported to be one of the key factors related to postoperative outcomes after Total knee arthroplasty (TKA). However, no study reports the impact of JLOA on patient-reported outcome measures (PROMs) in fixed-bearing Medial Unicompartmental Knee Arthroplasty (FBM-UKA).

Objectives
The aim of our study is to evaluate the relationship between JLOA and PROMs after FBM-UKA compared to Matched TKA patients.

Methods
This is a single-centre, prospective, STROBE-compliant, propensity score matched (PSM) study approved by the institutional review board. All patients with medial varus osteoarthritis who underwent unilateral FBM-UKA or TKA with normal opposite knee were included. Test group (FBM-UKA) included patients operated with FBM-UKA. Matched TKA was taken as control. Primary outcome was to measure JLOAs by full-leg- length standing coronal radiographs and correlate with PROMs. PROMs were measured in terms of OKS and 2011 KSS PS.

Results
The study included a cohort of 56 patients (56 knees) in FBM-UKA group. Matched cohort included 168 patients in TKA group. At mean follow-up of 36±6.23 months, mean postoperative JLOA in normal and operated knee were 0.3 ± 2.4° and 0.7 ± 2.6°, respectively. The JLOA significantly positively correlated with the improvement of the OKS.

Conclusions
The JLOA after FBM-UKA was either horizontal or mildly medially tilted, which was statistically not significant and positively correlated with PROMs. An extreme medial tilt of the JLOA was associated with poorer postoperative outcomes of UKA.

Introduction: The cementless Oxford Unicompartmental Knee Replacement (OUKR) was introduced to minimise the risk of aseptic loosening. However, there is a concern that the fixation may fail in the long term or that the interference fit of the cementless tibial keel may cause early periprosthetic fractures. The aim is to determine the 15-year survival and functional outcome. Methods: 1000 consecutive cementless OUKR were implanted between 2004 and 2017 for the recommended indications of antero-medial osteoarthritis (981) or avascular necrosis (19). All were independently followed-up. Mean follow-up was 10 years (maximum 19 years). Survival was assessed using various endpoints. The primary outcome measure was the Oxford Knee Score (OKS). Results: There were 52 (5.2%) re-operations at a mean of 6 years (SD4.3). 43 (4.3%) of these were revisions. The most common causes for revision were lateral compartment arthritis (1.8%), pain (0.9%), bearing dislocation (0.8%) and infection (0.3%). There was one aseptic loosening, which was a femoral component within the first year, and no fractures related to the cementless components. The 15-year survival for revision was 92% (CI 88.8-95.9), for major revision needing revision components was 99% (CI98.2-100), and for all re-operations was 91% (CI87.6-94.9). The mean OKS was 42 (SD7.7) at 10 years and 40 (SD8.4) at 15 years. Conclusion: Cementless OUKR has excellent long-term functional outcomes and survival when the recommended indications and techniques are used. Long-term fixation was reliably achieved with only a single case (0.1%) of loosening. There were no early periprosthetic fractures.

Tilting subsidence of the tibial component is a poorly understood complication of the cementless Oxford Unicompartmental Knee Replacement (OUKR). The aim was to determine the incidence, pattern, risk factors, and outcome of tilting. 438 cementless OUKRs between 2004-2017 with post-operative and subsequent antero-posterior(AP) and lateral radiographs were identified. The tibias of x-rays pairs were overlapped to measure component angle change. To determine the accuracy, radiographs of 15 patients of radiostereometric analysis (RSA) were measured in the same manner. Based on the RSA data, 3⁰ tilt, the greatest expected error, was chosen as the tilting threshold. Identified cases with tilting were optimally matched based on several factors with a group of control with <2⁰ tilt on a 1:1 ratio. Several radiographic features on the post-operative images were measured on FIJI and compared between the two groups. Nineteen radiographs had tilting subsidence (4.3%). All tilted into valgus (4.4⁰SD1.7) or tilted posteriorly (3.9⁰SD1). After the initial tilting there was no further progression. Between the tilted and non-tilted groups, there were no significant differences in patient, implant, and surgical factors, 1 year Oxford Knee Score (45IQR9v45IQR12), revision (10.5%v2.9%). However, tilted cases featured greater degrees of component underhanging, deeper vertical overcut, and more externally rotated femoral component relative to the tibial component. Tilting subsidence is rare (4%) and has a tendency into valgus or posteriorly. If treated conservatively the components stop tilting, with no difference in clinical outcomes from those that did not tilt. A few surgical factors could potentially play a role in tilting.

Objectives: To develop a strategy to detect the postoperative overcorrection risk when implanting a medial UKA using preoperative radiographic data. Additionally, the study aimed to identify intraoperative protective factors that could help prevent overcorrection. Methods: Image-assisted robotic medial UKAs between 2022 and 2023 were included. Postoperative overcorrection was defined as a hip-knee-ankle angle (HKA) ≥180°. Receiver Operating Characteristic (ROC) curves were constructed to evaluate the predictive ability of: "preoperative HKA" (preHKA) measured on long-leg films, "preoperative stress HKA" (sHKA) (HKA measured on preoperative valgus stress x-rays), and the "estimated HKA" (eHKA) (HKA + JLCA). The area under the curve (AUC) was calculated to determine the best parameter for predicting the risk of overcorrection. Cut-off points were determined using the Youden method. A subanalysis was performed on patients at risk to determine if any specific cut-off value of residual laxity (sHKA - postoperative HKA) measured intraoperatively could be identified as a protective factor against overcorrection. Results: Eight cases of overcorrection over 95 patients were detected (8.4%, 8/95). The best overcorrection predictor was preHKA (AUC=0.96) with a cut-off point of 176° (Se=100%, Sp=86%), followed by eHKA (AUC=0.94) with a cut-off point of 179.7° (Se=100%, Sp=86%), and sHKA (AUC=0.81) with a cut-off point of 181.3° (Se=100%, Sp=85%). In the subgroup of 20 patients with preHKA ≥176°, a residual laxity >2.6° was found to be a protective factor against overcorrection (p<.04). Conclusions: PreHKA ≥176° was the best overcorrection predictor. In this population, a residual laxity >2.6° was identified as a protective factor against overcorrection.

Objectives: The objective of this study was to describe a planning method for medial UKA implantation using preoperative stress radiographs to measure the thickness of tibial and femoral bone resections, and to validate it with an image-based robotic surgery system data. Methods: 76 patients who underwent image-based robotic medial UKA were included. Preoperative anteroposterior valgus stress knee radiographs were used to simulate UKA implantation based on Cartier's angle and aimed at restoring the joint line. Measured gap was 14mm (8mm for minimal tibial component and polyethylene insert + 4mm for femoral component + 2mm for safety laxity). Bone resections were measured in preoperative valgus stress radiographs and compared with the robotic system intraoperative bone resection data. Results: The mean planned radiographic tibial resection was 4.3 ± 0.4 [2.9-5.8], while the mean robotic resection was 4.2 ± 0.5 [2.7-5.8]. There was a strong correlation between these two values (P < 0.001). The mean planned radiographic femoral bone resection was 2.7 mm ± 0.7 [1-4.5], while the mean robotic resection was 2.5 ± 0.9 [1-5]. There was a strong correlation between these two values (P < 0.001). Intra- and inter-observer reliability were strong (P < 0.001 and P < 0.001, respectively). Conclusions: This study describes and validates a simple and reproducible preoperative planning method to determine femoral and tibial bone resection for medial UKA implantation. It represents a very valuable contribution to the understanding of UKA principles, which can serve to extend its indications, and increase reproducibility of the surgical technique.

Introduction Multiple strategies, used either in isolation or combination, are available to reduce the need for post-operative blood transfusion in joint replacements. Amongst them, the use of tranexamic acid (TXA) has been rising and this study was conducted to compare the efficacy of topical and intravenous TXA in bilateral total knee replacement patients. Materials and methods Randomised prospective study with 120 patients (male: female:: 25:95) undergoing bilateral TKA. Patients were divided into two groups A and B after computer randomization, who received intravenous or topical (intra-articular) TXA respectively. Results The average haemoglobin loss in intravenous group was 90.2379 g/L as compared to 39.137g/L in topical group (p<0.005).Moreover, there was reduction in blood loss in topical (330.1602 ml) as compared to intravenous group (764.9622 ml). The blood transfusion rate was more for the intravenous group (average 1.73 units) than for the topical group (average 0.75, unit). WOMAC score at 6 weeks in the intravenous group was 12.50, and in the topical group was 7.23 (p value <0.001). Conclusion Topical TXA is better than intravenous TXA for reduction of blood loss, which also reduces the need for blood in bilateral TKA patients.

The perioperative amount of blood loss among patients who undergo total knee arthroplasty (TKA) surgery is a significant cause of concern. Tranexamic acid administration have been described to reduce blood loss in TKA by various routes. This study aim to assess the topical tranexamic acid (TXA) efficacy in reducing blood loss in unilateral TKA surgery at 3 different doses; 1,2 and 3 grams. This was a prospective, randomized, double-blinded study involving 57 patients, undergoing unilateral TKA surgery. The patients were randomized to receive an intraarticular dose of either 1, 2 or 3 g of TXA in 50 mL of normal saline solution after capsule closure through the drain that was inserted intraarticularly. The tamponade effect was maintained for 4 hours before the drains were unclamped. Pre-operative and 48 hours postoperative haemoglobin (Hb), haematocrit (HCT) level, and drain output at 24 and 48 hours were recorded. The mean difference between preoperative and postoperative Hb and HCT for group 1,2 and 3 g were 1.36g/Dl,1.40g/dL,1.23g/dL (p=0.747) and 4.15%, 4.26%,4.27% respectively (p=0.950). The mean volume of drain output at 48 hours was 336.84 mL,313.68 mL and 263.68 mL respectively (p=0.195). This study found no significant difference in dosage in terms of blood loss, however topical TXA exhibited a more promising result than other routes. However topical TXA exhibited a more promising effect with additional tamponade effect than other routes.

Background: Cryotherapy is a nonpharmacologic option that complements drug therapy to achieve the most comprehensive multimodal analgesia. Various techniques include gel cold packs, cryo-cuffs, and mobile cold compressive devices (MCCD). This study aimed to evaluate and compare the efficacy and satisfaction among three cryotherapy devices in patients undergoing TKA.
Methods: This randomized study included 108 patients scheduled for primary TKA. The patients were allocated to three groups for cryotherapy techniques: gel cold pack, cryo-cuff, and MCCD. All devices were applied immediately after surgery and replaced every 8 hours during the hospital stay. The visual analog scale (VAS), morphine consumption, knee range of motion, knee swelling, length of hospital stay, and patient satisfaction were collected.
Results: Postoperative VAS showed a significant difference among the groups at 8 and 72 hours after surgery (p=0.002 and 0.026). Post hoc analysis demonstrated that patients in the MCCD group had lower pain scores than the cryo-cuff group (p<0.001). However, cryo-cuff reduced knee swelling significantly compared to gel cold pack and MCCD at postoperative 72 hours (p=0.01 and <0.001). The satisfaction survey demonstrated a total satisfaction score of 86.8, 82.8, and 89.1 with gel cold pack, cryo-cuff and MCCD.
Conclusion: Cryotherapy is an adjunct to postoperative pain control after TKA at the surgical site. MCCD exhibits exceptional effectiveness in pain reduction in the early postoperative phase. On the other hand, knee swelling is well minimized by the cryo-cuff. However, any cryotherapy technique provides similar efficacy, and patients could use any cryotherapy method with their preferred device.

Considerable debates exist encompassing different clinical and functional pros and cons of performing same day BTKA. There is no clarity on the optimal time interval for staging the procedure. There are no clear recommendations on the ideal time interval in between 2 surgeries in patients undergoing bilateral sequential TKA.The purpose of this study is to analyze the outcomes of sequential Bilateral Total knee Arthroplasty (BTKA) performed at time interval between 5-14 days.
Materials & Methods:
All patients undergoing sequential TKA within 5-14 days due to associated comorbidities were recruited and prospectively analysed over a span of 2 years. The functional outcomes were assessed after 6 months using the oxford knee society score (OKS), Visual analogue score (VAS), American knee society score (AKSS), and short form 12 (SF12) questionnaire.

Results:
57 patients undergoing sequential TKA were recruited and analysed.The mean age was 61.8(37-82).22 of them were males and 35 of them were females. The mean BMI was 25.9. The mean interval between each knee TKA was 5.09(2-9 days)The mean Visual Analogue Score was 2.2 ± 1.5. The mean AKSS was 74.3 ± 14.6. The mean OKS was 10.7±6.6. The mean PCS12 was 52.1± 7.2 and the mean MCS12 was 60.2 ± 6.8.

Conclusion:
Sequential BTKA done within a short interval of 5-14 days is safe and gives good functional outcomes. Both surgeries can be performed over a single admission over a short interval between the two knees