Post-traumatic Knee Osteoarthritis Research Articles

Primary Title: Assessing the Efficacy of the Stop OsteoARthritis (SOAR) program: A randomized delayed-controlled trial in persons at increased risk of early onset post-traumatic knee osteoarthritis,

ObjectiveAssess the efficacy of an 8-week virtual, physiotherapist (PT)-guided knee health program (SOAR) to improve knee extensor strength in individuals at risk of post-traumatic knee osteoarthritis (PTOA). MethodIn this superiority, randomized delayed-control trial, persons aged 16-35 years, 1-4 years after a self-reported knee joint injury were randomly assigned (1:1) to receive the SOAR program immediately (experimental group) or after a 9-week delay (control group). SOAR includes 1) one-time Knee Camp (virtual PT-guided group education, knee assessment, 1:1 exercise and physical activity goal-setting); 2) Weekly personalized home-based exercise and physical activity program with tracking; 3) Weekly 1:1 PT counseling (virtual). The primary outcome was change in isokinetic knee extensor strength (baseline to 9-weeks). Additional outcomes included change in self-reported knee-related quality-of-life (QOL), self-efficacy, self-management and kinesiophobia, and physical activity (accelerometer) at 9 and 18-weeks. Linear regression models estimated the effect of the 8-week intervention at the primary endpoint (9-week). Results49 of 54 randomized participants completed the study (91%). Participants were a mean±SD age of 27±5.0 years, and 2.4±0.9 years post-injury. No mean between group differences for the primary (0.05; 95%CI: -0.10,0.19) or other outcomes were seen at 9 weeks except for greater improvements in perceived self-management (Partner in Health Scale; 11.3/96, 95%CI: 5.5,17.1) and kinesiophobia (Tampa Scale of Kinesiophobia; -4.4/33, 95%CI: -7.0,-1.8). ConclusionFor active persons with elevated risk of PTOA, an 8-week SOAR program did not change knee-related strength, QOL, self-efficacy, or physical activity, on average, but may benefit the ability to self-manage knee health and kinesiophobia.

ФУНКЦИОНАЛЬНАЯ ОЦЕНКА РЕЗУЛЬТАТОВ ПРОКСИМАЛЬНОЙ СЕГМЕНТАРНОЙ РЕЗЕКЦИИ МАЛОБЕРЦОВОЙ КОСТИ ПРИ ОСТЕОАРТРОЗЕ МЕДИАЛЬНОГО ОТДЕЛА КОЛЕННОГО СУСТАВА

Osteoarthritis (OA) of the knee joint is the commonest form of OA. It occurs commonly in the medial compartment because of a preponderance of varus knees. High tibial osteotomy, total knee replacement and unicompartmental knee replacement are technically demanding procedures, while proximal segmental fibular resection (PSFR) significantly relieves pain and improves joint function in knee osteoarthritis (OA). This study was conducted at the department of traumatology and orthopedics at the Belarusian state medical university. The objective of this study was to assess functional outcomes after PSFR and its correlation with bone mineral density. 23 patients with unicompartmental OA with varus deformity were included in the study. Inclusion criteria included patients with moderate-to-severe symptomatic medial unicom- partmental OA of the knee, who had an indication for a surgical procedure, and who were able to give informed consent for the surgery. Exclusion criteria included patients with posttraumatic knee OA or inflammatory joint disease and patients with a history of previous operations or fractures the primary outcome was measured by calculating the ratio of knee joint space. The secondary outcome measure was pain measured by the visual analog scale (VAS).

Streamlining quantitative joint-wide medial femoro-tibial histopathological scoring of mouse post-traumatic knee osteoarthritis models

Histological scoring remains the gold-standard for quantifying post-traumatic osteoarthritis (ptOA) in animal models, allowing concurrent evaluation of numerous joint tissues. Available systems require scoring multiple sections/joints making analysis laborious and expensive. We investigated if a single section allowed equivalent quantitation of pathology in different joint tissues and disease stages, in three ptOA models. Male 10-12-week-old C57BL/6 mice underwent surgical medial-meniscal-destabilization, anterior-cruciate-ligament (ACL) transection, non-invasive-ACL-rupture, or served as sham-surgical, non-invasive-ACL-strain, or naïve/non-operated controls. Mice (n = 12/group) were harvested 1-, 4-, 8-, and 16-weekpost-intervention. Serial sagittal toluidine-blue/fast-green stained sections of the medial-femoro-tibial joint (n = 7/joint, 84 µm apart) underwent blinded scoring of 40 histology-outcomes. We evaluated agreement between single-slide versus entire slide-set maximum or median scores (weighted-kappa), and sensitivity/specificity of single-slide versus median/maximum to detect OA pathology. A single optimal mid-sagittal section showed excellent agreement with median (weighted-kappa 0.960) and maximum (weighted-kappa 0.926) scores. Agreement for individual histology-outcomes was high with only 19/240 median and 15/240 maximum scores having a weighted-kappa ≤0.4, the majority of these (16/19 and 11/15) in control groups. Statistically-significant histology-outcome differences between ptOA models and their controls detected with the entire slide-set were reliably reproduced using a single slide (sensitivity >93.15%, specificity >93.10%). The majority of false-negatives with single-slide scoring were meniscal and subchondral bone histology-outcomes (89%) and occurred in weeks 1-4 post-injury (84%). A single mid-sagittal slide reduced the time needed to score diverse histopathological changes by 87% without compromising the sensitivity or specificity of the analysis, across a variety of ptOA models and time-points.

Intervention Progress of Anterior Cruciate Ligament (ACL) Reconstruction in Knee Osteoarthritis Caused by ACL Injury

In recent years, as the number of people exercising has increased, so has the number of sports injuries, including traumatic osteoarthritis caused by Anterior Cruciate Ligament ACL injury. Traumatic osteoarthritis is a disease caused by trauma to or around the joints. It is primarily distinguished by articular cartilage degradation and ossification, which can lead to pathological changes of periarticular ligaments, synovial inflammation and joint instability, mainly causing joint pain, dysfunction, including premature joint degradation and other clinical symptoms. Any age and age group can occur, generally to young adults more common. The treatment of ACL injury is generally divided into emergency care, surgical treatment, drug treatment, and non-surgical treatment. If patients have ACL injury combined with medial knee ligament injury, or combined with posterior cruciate ligament injury and lateral ligament injury, surgical repair is generally selected for treatment, or ligament reconstruction is selected for treatment. For patients with obsolete injuries, more treatment means of ligament reconstruction should be considered. The therapeutic effect of ACL reconstruction on post-traumatic osteoarthritis is still controversial. This article aims to review the relationship between ACL injury and the pathogenesis of post traumatic knee osteoarthritis, in order to provide assistance for the treatment of Osteoarthritis of the knee caused by a severe injury.

Impaired synovial macrophage-mediated efferocytosis in a rat model of post-traumatic knee osteoarthritis

Impaired synovial macrophage-mediated efferocytosis in a rat model of post-traumatic knee osteoarthritis

Opioid Usage And Associated Healthcare Costs In Patients With Post-Traumatic Knee Osteoarthritis

Opioid Usage And Associated Healthcare Costs In Patients With Post-Traumatic Knee Osteoarthritis

Degenerative changes through MR cartilage mapping in anterior cruciate ligament-reconstructed knees

BackgroundAnterior cruciate ligament (ACL) injury increases risk for post traumatic knee osteoarthritis. ACL injury causes lack of knee stability and frequently requires ACL-reconstruction (ACLR) in order to restore functional and anatomical joint stability. Magnetic resonance imaging with T2 mapping sequence is used to quantify the amount of water content in articular cartilage hence; it is considered a better tool and more beneficial than radiographic based assessment in early detection even before being symptomatic. The aim of work is to estimate the incidence of subclinical degenerative changes that happened early in patients who underwent ACL reconstruction and to identify the correlations of T2 mapping values with patients' BMI, meniscal state/operations, ACL graft assessment and presence of ACLR related complications.ResultsThe study was conducted upon 71 patients, divided into 61 anterior cruciate ligament reconstructed knees and 10 control cases using 1.5 T MRI. Assessment of cartilage sub-compartment T2 values and comparison with average normal cartilage T2 values obtained from the control group. Multiple correlations of the grade of articular cartilage degeneration within anterior cruciate ligament reconstructed knees with Body Mass Index (BMI), time of operation as well associated meniscal operations and anterior cruciate ligament graft complications.ConclusionsAdding the T2 cartilage mapping sequence improves the ability to detect subclinical early degenerative articular cartilage changes in patients who underwent anterior cruciate ligament reconstruction, taking into consideration the relation of the patients' BMI, previous meniscal injuries/operation, ACL graft status and related graft complications with the T2 cartilage mapping values.

Comparison of discrete and continuous analysis approaches for evaluating gait biomechanics in individuals with anterior cruciate ligament reconstruction

BackgroundAberrant gait biomechanics contribute to post-traumatic knee osteoarthritis development following anterior cruciate ligament reconstruction (ACLR). Walking gait biomechanics are typically evaluated post-ACLR by identifying discrete, peak values in the load acceptance phase of gait (i.e. first 50 %). As these approaches evaluate a single time instant during the gait cycle, functional data analysis (FDA) techniques that evaluate the entire stance phase waveform are becoming more common in the literature. However, it is unclear if these analysis approaches identify the same biomechanical phenomena. Research questionThe purpose of this study was to determine whether four gait biomechanics analysis approaches identify the same aberrant gait characteristics in individuals with ACLR. MethodsTwenty-four individuals with ACLR and 24 healthy controls completed gait analyses on an instrumented treadmill. Four analysis approaches were employed to compare the vertical ground reaction force and sagittal knee angles and moments during the first 50 % of the stance phase between groups and between limbs in the ACLR cohort: 1) comparison of peak values from individual trials (Peak), 2) comparison of peak values from time-normalized ensemble waveforms (Ensemble Peak), 3) FDA via functional ANCOVA (FANCOVA), and 4) FDA evaluating overlap of the 95 % confidence intervals for each waveform (FDA-CI). ResultsThe Peak, Ensemble Peak, and FANCOVA approaches identified highly similar group and limb differences in the biomechanics outcomes with respect to both magnitude and temporal location. However, the FANCOVA approach indicated that these differences were distributed across large portions of the load acceptance phase and that differences existed outside the first 50 % of stance. The FDA-CI approach was generally not effective for identifying aberrant gait biomechanics. SignificancePeak and FANCOVA approaches to gait analysis provide similar findings. Future research is necessary to determine if the additional information afforded by FANCOVA provides insight regarding the mechanical pathogenesis of post-traumatic knee osteoarthritis.

Teriparatide ameliorates articular cartilage degradation and aberrant subchondral bone remodeling in DMM mice.

Knee osteoarthritis (KOA) is a highly prevalent musculoskeletal disorder characterized by degeneration of cartilage and abnormal remodeling of subchondral bone (SCB). Teriparatide (PTH (1-34)) is an effective anabolic drug for osteoporosis (OP) and regulates osteoprotegerin (OPG)/receptor activator of nuclear factor ligand (RANKL)/RANK signaling, which also has a therapeutic effect on KOA by ameliorating cartilage degradation and inhibiting aberrant remodeling of SCB. However, the mechanisms of PTH (1-34) in treating KOA are still uncertain and remain to be explored. Therefore, we compared the effect of PTH (1-34) on the post-traumatic KOA mouse model to explore the potential therapeutic effect and mechanisms. In vivo study, eight-week-old male mice including wild-type (WT) (n​=​54) and OPG-/- (n​=​54) were investigated and compared. Post-traumatic KOA model was created by destabilization of medial meniscus (DMM). WT mice were randomly assigned into three groups: the sham group (WT-sham; n​=​18), the DMM group (WT-DMM; n​=​18), and the PTH (1-34)-treated group (WT-DMM​+​PTH (1-34); n​=​18). Similarly, the OPG-/- mice were randomly allocated into three groups as well. The designed mice were executed at the 4th, 8th, and 12th weeks to evaluate KOA progression. To further explore the chondro-protective of PTH (1-34), the ATDC5 chondrocytes were stimulated with different concentrations of PTH (1-34) in vitro. Compared with the WT-sham mice, significant wear of cartilage in terms of reduced cartilage thickness and glycosaminoglycan (GAG) loss was detected in the WT-DMM mice. PTH (1-34) exhibited cartilage-protective by alleviating wear, retaining the thickness and GAG contents. Moreover, the deterioration of the SCB was alleviated and the expression of PTH1R/OPG/RANKL/RANK were found to increase after PTH (1-34) treatment. Among the OPG-/- mice, the cartilage of the DMM mice displayed typical KOA change with higher OARSI score and thinner cartilage. The damage of the cartilage was alleviated but the abnormal remodeling of SCB didn't show any response to the PTH (1-34) treatment. Compared with the WT-DMM mice, the OPG-/--DMM mice caught more aggressive KOA with thinner cartilage, sever cartilage damage, and more abnormal remodeling of SCB. Moreover, both the damaged cartilage from the WT-DMM mice and the OPG-/--DMM mice were alleviated but only the deterioration of SCB in WT-DMM mice was alleviated after the administration of PTH (1-34). In vitro study, PTH (1-34) could promote the viability of chondrocytes, enhance the synthesis of extracellular matrix (ECM) (AGC, COLII, and SOX9) at the mRNA and protein level, but inhibit the secretion of inflammatory cytokines (TNF-α and IL-6). Both wear of the cartilage was alleviated and aberrant remodeling of the SCB was inhibited in the WT mice, but only the cartilage-protective effect was observed in the OPG-/- mice. PTH (1-34) exhibited chondro-protective effect by decelerating cartilage degeneration in vivo as well as by promoting the proliferation and enhancing ECM synthesis of chondrocytes in vitro. The current investigation implied that the rescue of the disturbed SCB is dependent on the regulation of OPG while the chondro-protective effect is independent of modulation of OPG, which provides proof for the treatment of KOA. Systemic administration of PTH (1-34) could exert a therapeutic effect on both cartilage and SCB in different mechanisms to alleviate KOA progression, which might be a novel therapy for KOA.

Research Advances in the Development of Post-Traumatic Knee Osteoarthritis with Abnormal Mechanical Load, Inflammation, and Hemarthrosis

Knee injuries predominantly caused by anterior cruciate ligament (ACL) rupture and meniscal harm are most frequent among young people and sports activities enthusiasts. Post-traumatic osteoarthritis (PTOA) occurs in 25-50% of people with knee injuries. Previous researchers have thought that cartilage damage is caused by PTOA, but a growing body of research suggests that inflammation plays a key role in the development of PTOA. Hemarthrosis from knee injury may exacerbate inflammation of PTOA, and although mechanical symptoms such as joint instability and joint twisting can be relieved by surgical treatment, they are less effective in preventing PTOA progression. In order to explore more effective anti-inflammatory treatment plans to forestall PTOA progression, this article intends to review and summarize the results of the results on the pathophysiological mechanism of post-traumatic intra-articular inflammation, so as to identify potential targets and timing for future PTOA prevention and treatment, and provide theoretical guidance for clinical practice.

Dynamic knee stiffness during walking is increased in individuals with anterior cruciate ligament reconstruction

Individuals with anterior cruciate ligament (ACL) reconstruction often display abnormal gait mechanics reflective of a “stiff-knee” gait (i.e., reduced knee flexion angles and moments). However, dynamic knee stiffness, which is the dynamic relationship between the position of the knee and the moment acting on it, has not been directly examined during walking in individuals with ACL reconstruction. Here, we aimed to evaluate dynamic knee stiffness in the involved compared to the uninvolved limb during weight-acceptance and mid-stance phases of walking. Twenty-six individuals who underwent ACL reconstruction (Age: 20.2 ± 5.1 yrs., Time post-op: 7.2 ± 0.9 mo.) completed an overground walking assessment using a three-dimensional motion capture system and two force plates. Dynamic knee stiffness (Nm/°) was calculated as the slope of the regression line during weight-acceptance and midstance, obtained by plotting the sagittal plane knee angle versus knee moment. Paired t-tests with Bonferroni corrections were used to compare differences in dynamic stiffness, knee excursions, and moment ranges between limbs during both stance phases. Greater dynamic knee stiffness was found in the involved compared with the uninvolved limb during weight-acceptance and mid-stance (p < 0.01). Knee flexion and extension excursions were reduced in the involved limb during both weight-acceptance and mid-stance, respectively (p < 0.01). Sagittal plane knee moment ranges were not different between limbs during weight-acceptance (p = 0.1); however, the involved limb moment range was reduced relative to the uninvolved limb during mid-stance (p < 0.01). These results indicate that individuals with ACL reconstruction walk with a stiffer knee throughout stance, which may influence knee contact forces and could contribute to the high propensity for post-traumatic knee osteoarthritis development in this population.

Medial meniscus extrusion is directly correlated with medial tibial osteophyte in patients received reconstruction surgery for anterior cruciate ligament injury: A longitudinal study

ObjectiveAnterior cruciate ligament (ACL) injury is one of the causes for post-traumatic knee osteoarthritis (OA), and ACL reconstruction surgery is reportedly unable to prevent OA development. In early-stage knee OA, medial meniscus extrusion (MME) is closely correlated with tibial medial osteophyte width, which consists of bone and cartilage -parts. However, the relationship between MME and osteophyte in ACL-injured patients remains elusive. We examined MME and osteophyte and their relationship in ACL-injured patients before and after surgery. DesignThirty ACL-injured patients who underwent surgery (30.7 years old, on average) were enrolled. Correlations between magnetic resonance imaging (MRI)-detected OA changes and MME before and after surgery (7.6 months interval) were analyzed. ResultsMME (>3 ​mm) was present in 16.7% and 26.7% of the patients before and after surgery, respectively, and MME was significantly increased after surgery (2.4 ​± ​1.3 ​mm) than before surgery (1.9 ​± ​1.2 ​mm) (p ​< ​0.0001). Full-length tibial osteophyte width measured by T2 mapping MRI was significantly increased after surgery (1.9 ​± ​0.7 ​mm) than before surgery (1.4 ​± ​0.6 ​mm) (p ​< ​0.0001). Among OA structural changes, only medial tibial osteophyte width directly correlated with MME before surgery (β ​= ​0.962) (p ​< ​0.001) and after surgery (β ​= ​0.928) (p ​= ​0.001). All the patients with MME had medial tibial osteophyte before and after surgery. A direct correlation was observed between changes of MME and those of medial tibial osteophyte width before and after surgery (r ​= ​0.63) (p ​< ​0.0001). ConclusionMME and medial tibial osteophyte were simultaneously increased after surgery. In addition to close correlation between MME and medial tibial osteophyte width, changes of MME and medial tibial osteophyte width before and after surgery were directly correlated.

A review of Risk Factors for Post-traumatic hip and knee osteoarthritis following musculoskeletal injuries other than anterior cruciate ligament rupture.

Post-traumatic osteoarthritis (PTOA) is a common form of osteoarthritis that might occur after any joint trauma. Most PTOA publications mainly focus on anterior cruciate ligament (ACL) injuries. However, many other traumatic injuries are associated with PTOA, not only for the knee but also for the hip joint. We aim to identify and summarize the existing literature on the musculoskeletal injuries associated with knee and hip PTOA and their risk factors in determining those with a worse prognosis, excluding ACL injuries. Despite the narrative nature of this review, a systematic search for published studies in the last twenty years regarding the most relevant injuries associated with a higher risk of PTOA and associated risk factors for OA was conducted. This review identified the six more relevant injuries associated with knee or hip PTOA. We describe the incidence, risk factors for the injury and risk factors for PTOA of each. Meniscal injury, proximal tibial fracture, patellar dislocation, acetabular, femoral fractures and hip dislocations are all discussed in this review.

Tibial condylar valgus osteotomy for the treatment of intra-articular varus deformity of the knee.

The increasing incidence and distribution of primary and post-traumatic knee osteoarthritis (OA) in the young, active population has renewed interest in joint-preserving procedures. High tibial osteotomy (HTO) represents the most common treatment for medial knee OA associated with varus tibial deformity. However, deformities may also be related to intra-articular defects that an extra-articular procedure could not correct. The tibial condylar valgus osteotomy (TCVO) represents an intra-articular surgical technique for treating advanced medial knee OA with lateral joint subluxation. Currently, only a few papers with small samples and limited follow-up report the use of TCVO for the treatment of intra-articular deformities. Indications and operative techniques are various and not standardized. After an extensive search of PubMed, Scopus and Cochrane library, the main purpose of this paper is to summarize and discuss the indications, surgical techniques, and outcomes of intra-articular osteotomies while also reporting the preoperative planning and surgical procedure performed at our institution. These characteristics allow earlier weight-bearing and faster complete recovery. TCVO is an effective procedure to correct lower limbs' intra-articular defects from degenerative conditions developmental and post-traumatic deformities. This surgical technique, working at the intra-articular level, leads to some benefits related to restoring joint congruence and stability by realigning the axis of the lower limb and reducing the lateral joint subluxation. Moreover, the improved valgisation and lateralization of the mechanical axis and the limitation of the osteotomy to the medial condyle led to a better load distribution to the not osteotomy-involved compartment.

ACLD patients exhibit additional knee kinematic asymmetries at the speed level of healthy subjects.

Anterior cruciate ligament deficiency (ACLD) patients tend to walk slowly but try to catch up with the speed level of healthy subjects daily. Exploring the effects of the walking speed level of healthy subjects on the ACLD patients’ knee kinematics is important to improving non-operative treatments and delaying the progression of posttraumatic knee osteoarthritis. This study aimed to explore whether healthy controls’ walking speed level leads to additional knee kinematic asymmetries in patients with ACLD. 27 ACLD patients and 29 healthy controls were recruited for the study. The ACLD patients walked at two levels of walking speed, including self-selected and healthy controls’ walking speed levels. A three-dimensional gait analysis system was used to collect their knee kinematic data. ACLD patients exhibited more kinematic asymmetries when walking at healthy controls’ walking speed level than at their self-selected speeds. The kinematic asymmetries included increased posterior tibial translation (4.6 mm) and anteroposterior tibial ROM (3.9 mm), abduction angle (1.5°), and distal tibial translation (3.2 mm) asymmetries (p < 0.05). Our findings are meaningful for developing non-operative treatment strategies for patients with ACLD. To get fewer knee kinematic asymmetries, self-selected walking speed could be suggested for patients with ACLD daily rather than the speed levels of healthy subjects.

Post-traumatic knee osteoarthritis; the role of inflammation and hemarthrosis on disease progression.

Knee injuries such as anterior cruciate ligament ruptures and meniscal injury are common and are most frequently sustained by young and active individuals. Knee injuries will lead to post-traumatic osteoarthritis (PTOA) in 25–50% of patients. Mechanical processes where historically believed to cause cartilage breakdown in PTOA patients. But there is increasing evidence suggesting a key role for inflammation in PTOA development. Inflammation in PTOA might be aggravated by hemarthrosis which frequently occurs in injured knees. Whereas mechanical symptoms (joint instability and locking of the knee) can be successfully treated by surgery, there still is an unmet need for anti-inflammatory therapies that prevent PTOA progression. In order to develop anti-inflammatory therapies for PTOA, more knowledge about the exact pathophysiological mechanisms and exact course of post-traumatic inflammation is needed to determine possible targets and timing of future therapies.

Distribution and Correlates of Hip-Knee-Ankle Angle in Early Osteoarthritis and Preoperative Total Knee Arthroplasty Patients.

Several studies have investigated the distribution of hip-knee-ankle (HKA) angle in healthy populations; however, few have evaluated this metric in patients undergoing total knee arthroplasty (TKA). The purpose of this study is to compare HKA angle distribution in early and advanced knee osteoarthritis (OA) patients. Full limb radiographs were used to measure HKA angle for 983 subjects from the Osteoarthritis Initiative (OAI) cohort and 4,901 pre-TKA patients from an institutional cohort. Measurements were made using a previously validated deep learning algorithm. Linear regression models were used to determine the association of HKA alignment angle with patient characteristics. The mean ± standard deviation HKA angle was-1.3° ± 3.2° in the OAI cohort and-4.1° ± 6.1° in the pre-TKA cohort. In the OAI cohort, normal alignment (64%) was the most common knee alignment followed by varus (29%), and valgus (7%). In pre-TKA patients, the most common alignment was varus (62%), followed by normal (27%) and valgus (11%). In pre-TKA patients, mean HKA angle in primary knee OA, post-traumatic knee OA, and rheumatoid arthritis patients were-4.3° ± 6.1°,-3.2° ± 6.4°, and-2.9° ± 6.1°, respectively. HKA angle was strongly associated (P < .001) with gender and body mass index. TKA patients have a wider alignment distribution and more severe varus and valgus alignment than individuals "at risk" for knee OA from the OAI cohort. These epidemiologic findings improve our understanding of HKA angle distribution and its correlation with demographic characteristics in early and late-stage arthritis.

Vastus medialis intramuscular fat is associated with reduced quadriceps strength, but not knee osteoarthritis severity

BackgroundVastus medialis intramuscular fat has been proposed to be a modifiable determinant of knee cartilage loss in patients with knee osteoarthritis. The objective was to determine whether vastus medialis intramuscular fat relates to osteoarthritis severity and quadriceps muscle strength in patients with non-traumatic and post-traumatic knee osteoarthritis. MethodsFor this cross-sectional study, participants with knee osteoarthritis were classified into two groups: non-traumatic (n = 22; mean age = 60 years) and post-traumatic (n = 19; mean age = 56 years). Healthy adults were included (n = 22; mean age = 59 years). A 3-Tesla magnetic resonance imaging was used to measure vastus medialis cross-sectional area and intramuscular fat. Isometric knee extensor muscle torque was assessed using an isokinetic dynamometer and normalized to body mass (Nm/kg). Knee osteoarthritis severity was assessed using standing antero-posterior radiographs (Kellgren-Lawrence scores). Regression analyses examined relationships between 1) vastus medialis intramuscular fat with knee osteoarthritis severity and osteoarthritis group, after accounting for sex and body mass index, and 2) knee extensor muscle torque with vastus medialis intramuscular fat, after accounting for sex and vastus medialis cross-sectional area. FindingsVastus medialis intramuscular fat was positively associated with body mass index (B = 0.321, P < 0.001), but not with osteoarthritis severity or group (P > 0.05). Higher vastus medialis intramuscular fat was associated with reduced knee extensor muscle torque (B = -0.040, P = 0.018). InterpretationGreater vastus medialis intramuscular fat was associated with lower quadriceps muscle strength in patients with knee OA. It is unclear whether this is due to the accumulation of vastus medialis intramuscular fat or other potential factors, such as diet and physical inactivity.

Concurrent validity and reliability of a semi-automated approach to measuring the magnetic resonance imaging morphology of the knee joint in active youth.

Post-traumatic knee osteoarthritis is attributed to alterations in joint morphology, alignment, and biomechanics triggered by injury. While magnetic resonance (MR) imaging-based measures of joint morphology and alignment are relevant to understanding osteoarthritis risk, time consuming manual data extraction and measurement limit the number of outcomes that can be considered and deter widespread use. This paper describes the development and evaluation of a semi-automated software for measuring tibiofemoral and patellofemoral joint architecture using MR images from youth with and without a previous sport-related knee injury. After prompting users to identify and select key anatomical landmarks, the software can calculate 37 (14 tibiofemoral, 23 patellofemoral) relevant geometric features (morphology and alignment) based on established methods. To assess validity and reliability, 11 common geometric features were calculated from the knee MR images (proton density and proton density fat saturation sequences; 1.5 T) of 76 individuals with a 3-10-year history of youth sport-related knee injury and 76 uninjured controls. Spearman's or Pearson's correlation coefficients (95% CI) and Bland-Altman plots were used to assess the concurrent validity of the semi-automated software (novice rater) versus expert manual measurements, while intra-class correlation coefficients (ICC2,1; 95%CI), standard error of measurement (95%CI), 95% minimal detectable change, and Bland-Altman plots were used to assess the inter-rater reliability of the semi-automated software (novice vs resident radiologist rater). Correlation coefficients ranged between 0.89 (0.84, 0.92; Lateral Trochlear Inclination) and 0.97 (0.96, 0.98; Patellar Tilt Angle). ICC estimates ranged between 0.79 (0.63, 0.88; Lateral Patellar Tilt Angle) and 0.98 (0.95, 0.99; Bisect Offset). Bland-Altman plots did not reveal systematic bias. These measurement properties estimates are equal, if not better than previously reported methods suggesting that this novel semi-automated software is an accurate, reliable, and efficient alternative method for measuring large numbers of geometric features of the tibiofemoral and patellofemoral joints from MR studies.

SEX DIFFERENCES IN PRE-EXISTING CLINICAL COMORBIDITIES AND PRESCRIBED TREATMENTS IN PATIENTS WITH POST-TRAUMATIC KNEE OSTEOARTHRITIS

Purpose: It is widely accepted that sex differences in prevalence, severity, pain, and mental health are present in patients with idiopathic knee OA. However, it is unknown if sex differences are also present in patients with PTOA or if treatment utilization changes between sexes. Given these distinct differences between PTOA and OA patients it is important to identify if there are sex differences in clinical comorbidities and treatment utilization for patients with PTOA. The purpose of this study was to describe the differences in medical comorbidity prevalence and treatment utilization between sexes in patients with post-traumatic knee osteoarthritis.