Aim. Patient quality of life (QoL) in untreated bone infection was compared to other chronic conditions and stratified by disease severity. Method. Patients referred for treatment of osteomyelitis (including fracture related infection) were identified prospectively between 2019 and 2023. Patients with confirmed infection completed the EuroQol EQ-5D-5L questionnaire. Clinicians blinded to EQ-index score, grouped patients according to JS-BACH Classification into ‘Uncomplicated’, ‘Complex’ or ‘Limited treatment options’. A systematic review of the literature was performed of other conditions that have been stratified using EQ-index score. Results. 257 patients were referred, and 219 had suspected osteomyelitis. 196 patients had long bone infection and reported an average EQ-index score of 0.455 (SD 0.343). 23 patients with pelvic osteomyelitis had an average EQ-index score of 0.098 (SD 0.308). Compared to other chronic conditions, patients with long-bone osteomyelitis had worse QoL when compared to different types of malignancy (including bladder, oropharyngeal, colorectal, thyroid and myeloma), cardiorespiratory disease (including asthma, COPD and ischaemic heart disease), psychiatric conditions (including depression, pain and anxiety), endocrine disorders (including diabetes mellitus), neurological conditions (including Parkinson's disease, chronic pain and radiculopathy) and musculoskeletal conditions (including osteogenesis imperfecta, fibrous dysplasia and x-linked hypophosphataemic rickets). QoL in long-bone infection was similar to conditions such as Prada-Willi syndrome, Crohn's disease and juvenile idiopathic arthritis. Patients who had a history of stroke or multiple sclerosis reported worse QoL scores compared to long-bone infection. Patients who had pelvic osteomyelitis gave significantly lower QoL scores when compared to all other conditions that were available for comparison in the literature. In long bone infection, 41 cases (21.0%) were classified as ‘Uncomplicated’, 136 (69.4%) as ‘Complex’ and 19 (9.7%) as ‘Limited treatment options available’. Within classification stratification, patients with ‘Uncomplicated’ long bone infections reported a mean EQ-index score of 0.618 (SD 0.227) which was significantly higher compared to ‘Complex’ (EQ-index: 0.410 SD 0.359, p=0.004) and ‘Limited treatment options available’ (EQ-index: 0.400 SD 0.346, p=0.007). Conclusions. Bone and joint infections have a significant impact on patient quality of life. It is much worse when compared to other common chronic conditions, including malignancy, cardiovascular and neurological diseases. This has not been previously reported but may focus attention on the need for more investment in this patient group

Introduction. Reports cite up to 20% of total knee arthroplasty (TKA) patients are not satisfied. Recent focus on alignment and balance has perhaps overshadowed kinematics as a key determinant of outcomes. Some propose that reproducing the native knee kinematics of lateral-pivot motion in early flexion during walking will enact optimal TKA outcomes. The purpose of this study was to determine if intra-operative kinematic patterns correlate with patient function, pain and satisfaction after TKA. Methods. A retrospective review of consecutive TKA's performed by two surgeons was performed. After final components were implanted and balanced, sensor-embedded tibial trials were inserted and kinematic patterns were recorded through range-of-motion. Femoro-tibial contact points were recorded at four distinct flexion points (0°, 45°, 90° and full flexion). Center of rotation kinematic patterns were calculated and categorized as medial pivot, lateral pivot or translation at each measurement range via established criteria. Knees with lateral (L) pivot in early flexion between 0 and 45 ° and medial (M) pivot beyond 90°, regardless of the mid-flexion pivot pattern, formed the experimental group designated as LXM. All other patterns were designated non-LXM and formed the control group. Modern, validated clinical outcome measures (Knee Society Score, EQ5D, UCLA) were obtained preoperatively and at minimum one-year postoperatively. Results. 185 consecutive TKAs were analyzed and 33 were excluded due to sensor device malfunction, atypical hardware, unresurfaced patella, surgery at a non-study hospital, early infection, aseptic loosening revision, ipsilateral hip disease, or subsequent neurologic disease or death unrelated to the index TKA resulting in a final sample size of 152 patients. Twelve patients (7.9%) were lost to minimum one-year follow-up, and two were excluded from analysis due to outlier values. Seventy-five percent of the final sample was female. Mean age, height, weight, and BMI were 63.6 years, 167.0 cm, 94.5 kg, and 33.9, respectively. Patients in the LXM group tended to be slightly older (66 vs. 63 years, p = 0.062) and had fewer months of follow-up (18.3 vs. 21.6 months, p = 0.030). Controlling for age and follow-up, patients with the LXM kinematic pattern demonstrated better postoperative function scores (mean 74.6 vs. 66.3 points, p = 0.032) and greater functional improvement from preoperative baseline (mean 40.3 vs. 30.0 points, p = 0.001). The LXM kinematic pattern also was associated with greater improvement in the Knee Society objective score (mean 39.6 vs. 32.3 points, p = 0.053). There was a trend for LXM to demonstrate greater improvement in satisfaction (mean 20.1 vs. 17.3 points, p 0.086). EQ-5D health care quality of life and UCLA activity level score were unrelated to kinematic pattern. Conclusion. TKA patients with a lateral pivot kinematic pattern in the early range of motion and a medial pattern in high flexion beyond 90-degrees demonstrated superior functional outcomes and objective clinical knee scores. This supports the premise that TKA kinematic patterns that replicate native knee kinematics unique to certain degrees of flexion will have optimal function, improved clinical outcome, and less pain

INTRODUCTION. The purpose of TKA is to restore normal kinematics and functioning to diseased knees. The purpose of this study was to determine whether intraoperative kinematic data are correlated with minimum one-year outcomes following primary TKA. METHODS. We reviewed data on 185 consecutive primary TKAs in which sensor-embedded tibial trials were used to evaluate kinematic patterns following traditional ligament balancing. Procedures were performed by two board-certified arthroplasty surgeons. The same implant design and surgical approach was used for all knees. Contact locations on the medial and lateral condyles were recorded for each patient at 0°, 45° and 90° of flexion, and full flexion. Vector equations were created by contact locations on the medial and lateral sides and the vector intersections determined the center of rotation between each measurement position. Center of rotation was calculated as the average of vector intersections at 0 to 45°, 45 to 90°, and 90° to full flexion. If the average center of rotation was between 16 and 1000 mm of the contact location on the medial side it was considered a medial pivot knee. Knees were also classified as medial (16 to 200 mm on medial side), lateral (16 to 200 mm on lateral side), translating (> 200 mm medially or laterally), and other (< 16 mm on both medial and lateral sides). The new Knee Society Scoring System (KSSO objective score, KSSS satisfaction score, KSSF function score), the EQ-5D™ Health Status Index, and the University of California Los Angeles (UCLA) Activity Level Score were measured preoperatively and at minimum one-year follow-up (average 20.4 months). RESULTS. Thirty-three TKAs were excluded to eliminate potential bias due to sensor device malfunction, atypical hardware, unresurfaced patella, surgery at a non-study hospital, or early postoperative infection, revision due to aseptic loosening, ipsilateral hip disease, and subsequent neurologic disease or death unrelated to the index TKA, resulting in a final sample size of 152 knees. Twelve (7.9%) patients were lost to follow-up, and two were excluded due to outlier values for average center of rotation. Seventy-five percent of the final sample was female. Mean age and BMI were 63.6 years 33.9, respectively. Average center of rotation ranged from −1017 to 1562 mm with negative signifying the lateral side. Medial pivot knees comprised 40% (55) of the total sample. Sex, age, height, surgeon, implant side, and implant type were unrelated to pivot classification. Patient weight (100.2 vs. 90.9 kg; p = 0.012) and BMI (35.5 vs. 32.8; p = 0.044) were greater in medial pivot knees. Controlling for BMI, KSSO, KSSF, KSSS, EQ5D, UCLA, and pain scores at latest follow-up did not differ in medial and non-medial pivot knees (p ≥ 0.151). The amount of improvement in outcomes from preoperative baseline also did not differ in medial and non-medial pivot knees (p ≥ 0.161). Outcomes did not vary among knees with translating medial, lateral, and other pivots (p ≥ 0.065). DISCUSSION. Our results suggest that a medial pivot kinematic pattern may not be a substantial governor of clinical success