Contralateral Joint Research Articles

Humeral intracondylar fissures and intracondylar sclerosis are common CT findings in the limb contralateral to a humeral condylar fracture in French bulldogs and spaniel breeds.

French bulldogs (FBD) are reported to be at an increased risk of developing humeral condylar fractures (HCF). Spaniel breeds have been reported to be at increased risk of HCF due to a high prevalence of humeral intracondylar fissures (HIF), which can predispose to fracture. The aims of this retrospective, single center, observationalstudy were twofold. First, to comparethe signalment, fracture configuration, and etiology of populations of FBD and spaniel breeds presenting with HCF at a single hospital. Second, to evaluate the computed tomographic (CT) findings of the contralateral elbow joints of FBD and spaniel breeds presenting with HCF for concomitant pathology. FBDs were overrepresented for HCF, most commonly presenting when skeletally immature, with a median age of 3.7 months. Fractures of the lateral condyle were the most common configuration for both breed groups. Sclerosis at the fracture site was identified in 62% of FBD and 95% of spaniels undergoing CT scans. Humeral intracondylar fissures and intracondylar sclerosis were commonly observed in the contralateral elbows of FBD (44% and 50%, respectively) and spaniel breeds (58% and 95%, respectively). Medial coronoid pathology, elbow incongruency, and periarticular osteophytes were not identified in the contralateral elbows of FBD but were identified in 29%, 4%, and 20% of spaniels, respectively. The high prevalence of HIF in the FBD group may be a predisposing factor for HCF in this breed.

Posttraumatic Osteoarthritis of the Distal Interphalangeal Joint: A Follow-Up Study of 12 Years After Nonsurgical Treatment of Mallet Finger Fractures

In treatment of mallet finger fractures (MFFs), the aim is to minimize residual extension lag, reduce subluxation, and restore congruency of the distal interphalangeal (DIP) joint. Failure to do so may increase the risk of secondary osteoarthritis (OA). However, long-term follow-up studies focusing on OA of the DIP joint after an MFF are scarce. The purpose of this study was to assess OA, functional outcomes, and patient-reported outcome measures (PROMs) after an MFF. A cohort study was performed with 52 patients who sustained an MFF at a mean of 12.1 years (range, 9.9-15.5 years) previously and who were treated nonsurgically. A healthy contralateral DIP joint was used as the control. Outcomes were radiographic OA, using the Kellgren and Lawrence and Osteoarthritis Research Society International classifications, range of motion, pinch strength, and PROMs (Patient-Rated Wrist Hand Evaluation, Quick Disabilities of the Arm, Shoulder, and Hand, Michigan Hand Outcome Questionnaire, 12-item Short Form Health Survey). Radiographic OA was correlated with PROMs and functional outcomes. At follow-up, there was an increase in OA in 41% to 44% of the MFFs. Of all the MFFs, 23% to 25% showed a higher degree of OA than the healthy control DIP joint. Range of motion (mean difference ranging from-6° to-14°) and Michigan Hand Outcome Questionnaire score (median difference,-1.3) were decreased after MFFs but not to a clinically relevant extent. Radiographic OA was weakly to moderately correlated with functional outcomes and PROMs. Radiological OA after an MFF is similar to the natural degenerative process in the DIP joint and is accompanied by a decrease in range of motion of the DIP joint, which does not clinically affect PROMs. Therapeutic IV.

15 Unique yeast-derived prebiotic supports joint health and reduced systemic inflammation in senior horses

Senior horses are commonly afflicted with inflammation-related conditions including chronic or acute joint inflammation, and chronic low-grade systemic inflammation, or “inflamm-aging.” Reducing inflammation, where appropriate, may improve the quality of life and performance of senior horses. To that end, the objective of this trial was to determine whether supplementation of a unique yeast-derived prebiotic (ActivAge®(AA)) to senior horses would promote reduced joint and systemic inflammation. Aged Quarter horses (n = 10; mean age ± SEM = 21.3 ± 1.2yr; mean BW ± SEM = 587.5 ± 10.9kg; mean BCS ± SEM = 6.3 ± 0.2) were utilized in a crossover trial. Horses were randomly assigned to either a control (CON) or treatment (TRT) group. Horses in both groups were offered 4.54 kg/d Purina® Equine Senior® (CP = 14.5%, Ca = 0.76%, P = 0.61%). Horses were offered 1.25% BW as local grass hay (CP = 14.6%, Ca = 0.60%, P = 0.30%) daily. Horses were additionally offered 0.45 kg/d of a pellet containing AA (TRT) or not (CON). Daily ration was split into 2 equal feedings at 0700 and 1300 daily for 42d per period with a 28d washout period during which no TRT or CON pellet was offered. All horses had ad libitum access to fresh clean water and white salt. Serum samples were obtained via jugular venipuncture approximately 2hr post feeding every 2wk foranalysis of the acute phase protein, serum amyloid A (SAA; SAA-Vet, Eiken Chemical Co.). On d42 horses underwent a joint inflammation challenge. Briefly, 1mL of a sterile saline solution containing 0.5ng lipopolysaccharide from E. coli 055:B5 (Sigma-Aldrich) was injected into the radiocarpal joint. The contralateral joint was used as a control with only sterile saline injected. Synovial fluid was collected aseptically immediately before injection and at 5, 24, and 48hr post injection. All data were analyzed via ANOVA utilizing a MIXED procedure in SAS 9.4. Horses in the TRT group had no increase in SAA during supplementation while horses in CON increased by approximately 37% by d42 for a trt x time interaction (P < 0.001). Horses in the CON group in both the control and challenged joint had higher AUC for interleukin-6 (P = 0.02) and tumor-necrosis factor α (P = 0.01) than TRT horses. Interleukin-6 and TNFa were analyzed via species-specific colorimetric assays (RD Systems). Taken together, these data indicate that ActivAge® supplementation reduced systemic inflammation in senior horses while also supporting these horses during a joint inflammation challenge.

Association between chewing side preference and MRI characteristics in patients with anterior disc displacement of the temporomandibular joint

ObjectiveTo compare the magnetic resonance imaging (MRI) characteristics in the anterior disc displacement (ADD) patients with and without chewing side preference (CSP). MethodsThe MRI characteristics of the bilateral temporomandibular joint (TMJ) in 111 patients with ADD were retrospectively analysed. Based on the presence of CSP, all subjects were divided into the non-CSP group (NC group, N = 40) and CSP group (C group, N = 71). Based on the preferred chewing side in the C group, the patients were divided into ipsilateral and contralateral sides. The morphology, length, disc-condyle angle, and coordinate position of the disc and condyle of the bilateral TMJ were compared. ResultsMRI examination showed a significant difference between ipsilateral and contralateral joint displacement in patients with CSP (P<0.05). In CSP patients, the disc length of the same side in the ipsilateral side was significantly shorter than the contralateral side (P<0.05). A significant difference in the Y-axis coordinates of the ipsilateral and contralateral discs was also found in patients with CSP (P<0.05). The disc displacement grade, morphology of the articular disc, ipsilateral disc length, and ipsilateral disc-condyle Y-axis distance were positively correlated with CSP (P<0.05). ConclusionCSP is related to the shape of the articular disc and disc-condyle position in patients with ADD. CSP may aggravate the development of ADD.

Prediction of Contralateral Lower-Limb Joint Angles Using Vibroarthrography and Surface Electromyography Signals in Time-Series Network

Multisource biosignals are being increasingly used in human–machine interaction applications. In particular, a critical problem in exoskeleton-assisted rehabilitation for patients with hemiplegia is the generation of rhythmic and symmetrical locomotion. To support lower limb rehabilitation, we propose a model for predicting contralateral joint angles using multisource biosignals. First, a vibroarthrography (VAG) sensor is attached to the affected leg, and surface electromyography sensors are attached to the sound leg. The corresponding signals are used to estimate the hip, knee, and ankle joint angles of the affected leg. Second, an algorithm based on a temporal convolution network (TCN) is introduced to predict the contralateral lower-limb joint angles during human locomotion. The TCN is compared with a long short-term memory (LSTM) network and a convolutional neural network. Experiments were conducted by 10 healthy participants. The results of the proposed model were compared with measurements from encoders in three joints mounted on an exoskeleton to verify the applicability of the proposed model. In addition, by using the outputs of a motion capture system as the ground truth, the experimental results validated the model prediction performance. The prediction root mean square error (RMSE) of the TCN was 52%–70% lower than that of the LSTM network and CNN at different paces. The prediction RMSE using VAG was 20%–24% lower than that without using VAG. Note to Practitioners—We propose a model for predicting the contralateral lower-limb joint angles of an exoskeleton. The model uses measurements from multiple biosignal sensors to support exoskeleton-assisted hemiplegia rehabilitation. A sensing system based on acoustic signals and bioelectric signals is developed to improve the joint angle prediction in the affected leg of patients with hemiplegia. A temporal convolution network is implemented to estimate joint angles, and training considering the root mean square error and Pearson correlation coefficient as evaluation indicators is performed. Unlike similar methods that include no sensory feedback from the affected leg, the proposed method incorporates VAG signals from the affected leg and sEMG signals from the sound leg to handle different degrees of hemiplegia and support the generation of rhythmic and symmetrical locomotion for gait rehabilitation using an exoskeleton.

Case Report-Traumatic L5-S1 Instability: Are Upright Radiographs Potentially Dangerous?

Traumatic lumbosacral instability is a rare but potentially devastating injury. These injuries are frequently associated with neurologic injury and often result in long-term disability. Despite their severity, radiographic findings can be subtle, and multiple reports exist in which these injuries were not recognized on initial imaging. Transverse process fractures, high-energy mechanisms, and other injury features have been suggested as indications for advanced imaging, which has a high degree of sensitivity in detecting unstable injuries. A 21-year-old man presented to our level I trauma center after being ejected in a rollover motor vehicle collision. He sustained multiple injuries, including multiple lumbar transverse process fractures and a unilateral superior articular facet fracture of S1. Initial supine computed tomography (CT) images showed no displacement of the fracture and no listhesis or instability. Subsequent upright imaging in a brace, however, demonstrated significant displacement of the fracture with dislocation of the contralateral L5-S1 facet joint and significant anterolisthesis. The patient underwent open posterior reduction and stabilization of L4-S1 followed by L5-S1 anterior lumbar interbody fusion. The patient demonstrated excellent alignment on postoperative imaging. At 3 months postoperatively, he had returned to work, was ambulating without assistance, and reported minimal back discomfort and no lower extremity pain, numbness, or weakness. This case serves as a warning that supine CT imaging alone may not be sufficient to rule out unstable lumbar spine injuries, such as traumatic L5-S1 instability, and that upright radiographs in these potentially unstable injuries may represent a hazard to patients. Fractures involving the pedicle, pars, or facet joints as well as multiple transverse process fractures and/or a high-energy mechanism of injury should all raise suspicion of instability and warrant additional imaging. This article provides guidance on approaching treatment for patients with potential traumatic lumbosacral instability.

Effect of transtibial prosthesis weight on the contralateral knee joint in relation to the risk of osteoarthritis.

Individuals with transtibial amputation place more load on the contralateral lower extremity. A higher adduction moment at the knee joint has been shown to have an effect on the risk of osteoarthritis. The aim of this study was to investigate the effect of weight-bearing of lower-limb prosthesis on the biomechanical parameters associated with the risk of contralateral knee osteoarthritis. Cross-sectional. The experimental group of 14 subjects with unilateral transtibial amputation (13 males). The mean age was 52.7 ± 14.2 years, height 175.6 ± 6.3 cm, weight 82.3 ± 12.5 kg, and duration of prosthesis use 16.5 ± 9.1 years. The control group consisted of 14 healthy subjects with identical anthropometric parameters. Dual emission X-ray absorptiometry was used to determine the weight of the amputated limb. For gait analysis, 10 Qualisys infrared cameras and a motion sensing system on 3 Kistler force platforms were used. Gait was analyzed with the original, lighter, commonly used prosthesis, as well as the prosthesis loaded to the original limb weight. The gait cycle and kinetic parameters of the amputated and healthy limbs were more similar to those of the control group when using the weighted prosthesis. We recommend further research to more accurately specify the weight of the lower-limb prosthesis with respect to the prosthesis design and duration of use of the heavier prosthesis during the day.

Equine osteoarthritis modifies fatty acid signatures in synovial fluid and its extracellular vesicles

BackgroundIndividual fatty acids (FAs) and their derivatives (lipid mediators) with pro-inflammatory or dual anti-inflammatory and pro-resolving properties have potential to influence the health of joint tissues. Osteoarthritis (OA) is an age-associated chronic joint disease that can be featured with altered FA composition in the synovial fluid (SF) of human patients. The counts and cargo of extracellular vesicles (EVs), membrane-bound particles released by synovial joint cells and transporting bioactive lipids, can also be modified by OA. The detailed FA signatures of SF and its EVs have remained unexplored in the horse — a well-recognized veterinary model for OA research.MethodsThe aim of the present study was to compare the FA profiles in equine SF and its ultracentrifuged EV fraction between control, contralateral, and OA metacarpophalangeal joints (n = 8/group). The FA profiles of total lipids were determined by gas chromatography and the data compared with univariate and multivariate analyses.ResultsThe data revealed distinct FA profiles in SF and its EV-enriched pellet that were modified by naturally occurring equine OA. Regarding SFs, linoleic acid (generalized linear model, p = 0.0006), myristic acid (p = 0.003), palmitoleic acid (p < 0.0005), and n-3/n-6 polyunsaturated FA ratio (p < 0.0005) were among the important variables that separated OA from control samples. In EV-enriched pellets, saturated FAs palmitic acid (p = 0.020), stearic acid (p = 0.002), and behenic acid (p = 0.003) indicated OA. The observed FA modifications are potentially detrimental and could contribute to inflammatory processes and cartilage degradation in OA.ConclusionsEquine OA joints can be distinguished from normal joints based on their FA signatures in SF and its EV-enriched pellet. Clarifying the roles of SF and EV FA compositions in the pathogenesis of OA and their potential as joint disease biomarkers and therapeutic targets warrants future studies.

Analysis of Regeneration Tissue Formed in the Treatment of Cartilage Defects

Joint function losses that occur as a result of injury, healing and scarring of the cartilage tissue are varied. In this study, the contralateral joints of rabbits with complete cartilage loss were defined as the control group. Self-healing of similar cartilage losses and popular surgical methods were compared, and the results were examined histopathologically. As a result, it was determined that while autogenous full-thickness osteochondral cartilage transfer resulted in the best cartilage healing, the healed cartilage tissue without any intervention was superior to methods such as drilling and carbon fiber. We concluded that cartilage tissue must be “no men land” if lower than full thickness cartilage lesions. Cartilage must be protected any surgical impact instead of main mechanical articular problems must be focused.

Acute Effect of Unilateral Muscle Training Supported with Visual Feedback on Contralateral Muscle Strength and Joint Position Sense

Aim: Unilateral exercise training is an effective and useful technique, especially in immobilization and neurological conditions, but the effect of unilateral muscle exercise training on muscle strength is modest. Therefore, the aim of this study is to detect the acute concomitant effect of mirror therapy and unilateral exercise training on muscle strength and joint position sense in healthy adults.Method: Thirty-one participants were randomly enrolled in two groups the mirror (n=16) and control groups (n=15). Hand grip (HG), pinch grip (PG) strengths, and joint position sense (JPS) of the wrist were assessed in both hands before and after a single exercise session which include 300 repetitive ball squeezing exercises by right (exercised) hand for all groups. The participants in the mirror group were asked to watch the mirror to see the reflection of their exercised hands, the control group only watched their exercised and unexercised hands without any visual feedback support during the exercise session. Repeated Measure ANOVA and Mixed ANOVA tests were performed to analyze in- and between-group differences.Results: The statistically significant differences were determined in unexercised hand HG and PG strength in the mirror group (F=10,105; p=0,006, ηp2=0,403; F=5,341; p=0,035; ηp2=0,263, respectively). However, any group×time interaction was found in JPS, HG, or PG tests (p&amp;lt;0;05). Additionally, no difference was shown in JPS in-group comparisons (p&amp;lt;0;05).Conclusion: The result of the study suggested that unilateral exercise training should apply concomitant with visual feedback. Further studies are needed to compare the effect of different sensory feedbacks on unilateral exercise training.

Prediction of Subsequent Contralateral Patellar Dislocation after First-Time Dislocation Based on Patellofemoral Morphologies.

The subsequent dislocation of a contralateral patellofemoral joint sometimes occurs after a first-time lateral patellar dislocation (LPD). However, the anatomic risk factors for subsequent contralateral LPD remain elusive. This study included 17 patients with contralateral LPD and 34 unilateral patellar dislocators. The anatomic parameters of the contralateral patellofemoral joints were measured using CT images and radiographs that were obtained at the time of the first dislocation. The Wilcoxon rank-sum test was performed, and a binary regression model was established to identify the risk factors. The receiver operating characteristic curves and the area under the curve (AUC) were analyzed. The tibial tubercle-Roman arch (TT-RA) distance was significantly different between patients with and without contralateral LPD (24.1 vs. 19.5 mm, p < 0.001). The hip−knee−ankle (HKA) angle, patellar tilt, congruence angle, and patellar displacement were greater in the study group than in the control group (p < 0.05). The TT-RA distance revealed an OR of 1.35 (95% CI (1.26−1.44]), p < 0.001) and an AUC of 0.727 for predicting contralateral LPD. The HKA angle revealed an OR of 1.74 (95% CI (1.51−2.00), p < 0.001) and an AUC of 0.797. The Patellar tilt, congruence angle, and patellar displacement had AUC values of 0.703, 0.725, and 0.817 for predicting contralateral LPD, respectively. In conclusion, the contralateral patellofemoral anatomic parameters were significantly different between patients with and without subsequent contralateral LPD. Increased TT-RA distance and excessive valgus deformity were risk factors and could serve as predictors for contralateral LPD. At first-time dislocation, the abnormal position of the patella relative to the trochlea may also be an important cause of subsequent LPD.

Total Hip Arthroplasty in Patients With Post-Traumatic Bone Defects and Acetabular Deformities

Backround. Total hip replacement in cases of traumatic changes of the acetabulum refers to cases of difficult primary arthroplasty and requires detailed preoperative planning and accurate restoration of anatomical relationships in the operated joint.&#x0D; The aim of the study was to evaluate the structure of pathological changes in the acetabulum in patients with posttraumatic hip arthrosis, to develop a method for their detailed description and to determine the tactics of choosing the type of acetabulum implant.&#x0D; Methods. The results of treatment of 194 patients with the consequences of acetabulum fractures who underwent total hip arthroplasty in the period from 2014 to 2022 were analyzed. The study was conducted in two stages, at the first stage, the structure of pathological changes, such as defect, deformation, changes in the center of rotation and offset (relatively healthy contralateral joint), was analyzed. A method was developed for choosing the tactics of implantation of the acetabulum component, based on a detailed description of the defect and deformation of the acetabulum. The second stage analyzed the results of treatment of patients for whom planning and surgical treatment was carried out in the period from 2020 to 2022 using the proposed method.&#x0D; Results. During the first stage of the study, it was revealed that the magnitude of the change in the indicators of the displacement of the rotation center and offset changes by more than 8 mm. statistically significantly increases the likelihood of complications by 17.9%. The restoration of the rotation and offset center reduces the number of complications by 22.3%. The proposed method makes it possible to statistically reliably restore anatomical relationships in the operated hip joint and reduce the number of complications by 10%.&#x0D; Conclusion. The proposed method allows us to qualitatively and quantitatively describe pathological changes in the bone tissue of the acetabulum. Depending on the degree of displacement of the center of rotation, the walls of the acetabulum and the nature of the defect of the supporting bone tissue, the surgeon can determine the tactics of surgical treatment.

The biomechanical fingerprint of hip and knee osteoarthritis patients during activities of daily living

BackgroundOsteoarthritis is a highly prevalent disease affecting the hip and knee joint and is characterized by load-mediated pain and decreased quality of life. Dependent on involved joint, patients present antalgic movement compensations, aiming to decrease loading on the involved joint. However, the associated alterations in mechanical loading of the ipsi- and contra-lateral lower limb joints, are less documented. Here, we documented the biomechanical fingerprint of end-stage hip and knee osteoarthritis patients in terms of ipsilateral and contralateral hip and knee loading during walking and stair ambulation. MethodsThree-dimensional motion-analysis was performed in 20 hip, 18 knee osteoarthritis patients and 12 controls during level walking and stair ambulation. Joint contact forces were calculated using a standard musculoskeletal modelling workflow in Opensim. Involved and contralateral hip and knee joint loading was compared against healthy controls using independent t-tests (p < 0.05). FindingsBoth hip and knee cohorts significantly decreased loading of the involved joint during gait and stair ambulation. Hip osteoarthritis patients presented no signs of ipsilateral knee nor contralateral leg overloading, during walking and stair ascending. However, knee osteoarthritis patients significantly increased loading at the ipsilateral hip, and contralateral hip and knee joints during stair ambulation compared to controls. InterpretationThe biomechanical fingerprint in knee and hip osteoarthritis patients confirmed antalgic movement strategies to unload the involved leg during gait. Only during stair ambulation in knee osteoarthritis patients, movement adaptations were confirmed that induced unbalanced intra- and inter-limb loading conditions, which are known risk factors for secondary osteoarthritis.

Effects of Contralateral Hip Flexion Angle on the Ober Test.

The Ober test is an orthopedic evaluation procedure used to assess for tightness of the tensor fascia latae (TFL) and iliotibial band (ITB). Multiple versions of this test have been described using different degrees of contralateral hip joint flexion to stabilize the pelvis. The aim of this study was to analyze the hip range of motion (ROM) in the frontal plane and perceived tension produced during the Ober test using four different angles of contralateral hip flexion prepositioning. The secondary objective was to analyze the differences in the Ober test with different contralateral hip flexion angles according to limb dominance. This cross-sectional study included healthy individuals aged 18 years or older. The Ober test was performed on the right and left leg of each participant with the contralateral hip joint stabilized at 0° flexion, 45° flexion, 90° flexion, and maximal flexion. Hip range of motion in the frontal plane (abduction or adduction) was measured using a digital inclinometer. Three measurements were performed on each limb for every angle of contralateral prepositioning, using the average of the three measurements for statistical analysis. Participants were asked to report the location of any perceived tension and the intensity of tension using a Numeric Rating Scale during the test. Twenty-eight participants (17 men and 11 women) were examined. Significant differences in the Ober test hip ROM in the frontal plane (p < 0.01) were observed when comparing different angles of contralateral hip flexion prepositioning. Significant differences between tests were also present for intensity of perceived tension (p ≤ 0.001), except for the intensity of perceived tension between 0° and 45°. No statistically significant differences were observed related to limb dominance (p > 0.05) or gender (p > 0.05), except for the Ober test at 0° (p < 0.001) which was higher in men (9.61° ± 5.01°) than in women (5.05° ± 2.87°). Greater contralateral hip flexion prepositioning during the Ober test results in decreased hip adduction ROM in the tested limb and greater perceived tension in the region of tensor fascia latae-iliotibial band.

Ankle bone morphology affects the size of non-trauma related osteochondral lesions of the talus in skeletally immature children

BackgroundThis study aimed to elucidate the relationship between ankle morphology and the size of non-trauma related osteochondral lesions of the talus (OLT), because approximately half the OLT found in children is of unknown origin. Methods34 ankles in 30 skeletally immature children with OLTs who underwent preoperative magnetic resonance imaging (MRI) were evaluated. Parameters measured included area of the OLT, tibial axis-medial malleolus angle (TMM), malleolar width (MalW), and talar surface angle (TSA; defined as the angle between the line perpendicular to the mid-diaphysis of the tibia and the talar joint surface; medial inclination, positive). The ankles were divided into two groups: the trauma group had a history of injury and the idiopathic group had no history of injury. The correlation between lesion area and MRI parameters were evaluated in each group. ResultsThirteen ankles in 13 patients comprised the trauma group, while 21 ankles in 17 patients were in the idiopathic group. Of the 17 patients in the idiopathic group, four had bilateral OLT. In the trauma group, MalW was significantly correlated with the area (r = 0.827, P = 0.0001). In the idiopathic group, TMM and MalW were significantly correlated with the area (r = 0.608, P = 0.003 and r = 0.566, P = 0.008). TSA was positively correlated with area in the idiopathic group (r = 0.516, P = 0.017), but negatively correlated with area in the trauma group (r = −0.609, P = 0.027). The other parameters showed no significant correlation. ConclusionsThe size of non-trauma related OLTs may have been affected by an ankle morphology showing poor bone conformity, such as an open medial malleolus and inclined talar joint surface. In addition, the evaluation of the contralateral ankle joint may be crucial when patients with OLT have no specific history of trauma.

Homing of radiolabelled xenogeneic equine peripheral blood-derived MSCs towards a joint lesion in a dog.

Osteoarthritis (OA) is a highly prevalent condition in dogs, causing a substantial reduction in quality of life and welfare of the animals. Current disease management focusses on pain relief but does not stop the progression of the disease. Therefore, mesenchymal stem cells (MSCs) could offer a promising disease modifying alternative. However, little is known about the behavior and the mode of action of MSCs following their administration. In the current case report, 99mTechnetium labelled xenogeneic equine peripheral blood-derived MSCs were intravenously injected in a 9 year old dog suffering from a natural occurring cranial cruciate ligament rupture. The biodistribution of the MSCs was evaluated during a 6-h follow-up period, using a full body scintigraphy imaging technique. No clinical abnormalities or ectopic tissue formations were detected throughout the study. A radiopharmaceutical uptake was present in the liver, heart, lung, spleen, kidneys and bladder of the dog. Furthermore, homing of the radiolabelled MSCs to the injured joint was observed, with 40.61 % higher uptake in the affected joint in comparison with the healthy contralateral joint. Finally, a local radioactive hotspot was seen at a part of the tail of the dog that had been injured recently. The current study is the first to confirm the homing of xenogeneic MSCs to a naturally occurring joint lesion after IV administration.

Auricular surface morphology and surface area does not influence subchondral bone density distribution in the dysfunctional sacroiliac joint.

The subchondral lamella of the sacroiliac auricular surface is morphologically inconsistent. Its morpho-mechanical relationship with dysfunction (SIJD) remains unstudied. Here, the iliac and sacral subchondral bone mineralization is compared between morphological subtypes and in large and small surfaces, in SIJD joints and controls. CT datasets from 29 patients with bilateral or unilateral SIJD were subjected to CT-osteoabsorptiometry. Surface areas and posterior angles were calculated and surfaces were classified by size: small (<15 cm3 ) and large (≥15 cm3 ), and morphological types: 1 (>160°), 2 (130°-160°), and 3 (<130°). Mineralization patterns were identified: two marginal (M1 and M2) and two non-marginal (N1 and N2). Each sacral and iliac surface was subsequently classified. Dysfunctional cohort area averaged 15.0± 2.4 cm2 (males 16.2± 2.5 cm2 , females 13.7± 1.6 cm2 ). No age correlations with surface area were found nor mean Hounsfield Unit differences when comparing sizes, sexes or morphology-type. Controls and dysfunctional cohort comparison revealed differences in female sacra (p= 0.02) and small sacra (p= 0.03). There was low-conformity in marginal and non-marginal patterns, 26% for contralateral non-dysfunctional joints, and 46% for dysfunctional joints. The majority of painful joints was of type 2 morphology (59%), equally distributed between small (49%) and large joints (51%). Larger joints had the highest frequency of dysfunctional joints (72%). Auricular surface morphology seems to have little impact on pain-related subchondral lamella adaptation in SIJD. Larger joints may be predisposed to the onset of pain due to the weakening of the extracapsular structures. Dysfunctional joints reflect common conformity patterns of sacral-apex mineralization with corresponding superior corner iliac mineralization.

Intra-articular injection of epigallocatechin (EGCG) crosslinks and alters biomechanical properties of articular cartilage, a study via nanoindentation.

Osteoarthritis and rheumatoid arthritis are debilitating conditions, affecting millions of people. Both osteoarthritis and rheumatoid arthritis degrade the articular cartilage (AC) at the ends of long bones, resulting in weakened tissue prone to further damage. This degradation impairs the cartilage’s mechanical properties leading to areas of thinned cartilage and exposed bone which compromises the integrity of the joint. No preventative measures exist for joint destruction. Discovering a way to slow the degradation of AC or prevent it would slow the painful progression of the disease, allowing millions to live pain-free. Recently, that the articular injection of the polyphenol epigallocatechin-gallate (EGCG) slows AC damage in an arthritis rat model. It was suggested that EGCG crosslinks AC and makes it resistant to degradation. However, direct evidence that intraarticular injection of EGCG crosslinks cartilage collagen and changes its compressive properties are not known. The aim of this study was to investigate the effects of intraarticular injection of EGCG induced biomechanical properties of AC. We hypothesize that in vivo exposure EGCG will bind and crosslink to AC collagen and alter its biomechanical properties. We developed a technique of nano-indentation to investigate articular cartilage properties by measuring cartilage compressive properties and quantifying differences due to EGCG exposure. In this study, the rat knee joint was subjected to a series of intraarticular injections of EGCG and contralateral knee joint was injected with saline. After the injections animals were sacrificed, and the knees were removed and tested in an anatomically relevant model of nanoindentation. All mechanical data was normalized to the measurements in the contralateral knee to better compare data between the animals. The data demonstrated significant increases for reduced elastic modulus (57.5%), hardness (83.2%), and stiffness (17.6%) in cartilage treated with injections of EGCG normalized to those treated with just saline solution when compared to baseline subjects without injections, with a significance level of alpha = 0.05. This data provides evidence that EGCG treated cartilage yields a strengthened cartilage matrix as compared to AC from the saline injected knees. These findings are significant because the increase in cartilage biomechanics will translate into resistance to degradation in arthritis. Furthermore, the data suggest for the first time that it is possible to strengthen the articular cartilage by intraarticular injections of polyphenols. Although this data is preliminary, it suggests that clinical applications of EGCG treated cartilage could yield strengthened tissue with the potential to resist or compensate for matrix degradation caused by arthritis.

Counts of hyaluronic acid-containing extracellular vesicles decrease in naturally occurring equine osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease with inadequately understood pathogenesis leading to pain and functional limitations. Extracellular vesicles (EVs) released by synovial joint cells can induce both pro- and anti-OA effects. Hyaluronic acid (HA) lubricates the surfaces of articular cartilage and is one of the bioactive molecules transported by EVs. In humans, altered EV counts and composition can be observed in OA synovial fluid (SF), while EV research is in early stages in the horse—a well-recognized OA model. The aim was to characterize SF EVs and their HA cargo in 19 horses. SF was collected after euthanasia from control, OA, and contralateral metacarpophalangeal joints. The SF HA concentrations and size distribution were determined with a sandwich-type enzyme-linked sorbent assay and size-exclusion chromatography. Ultracentrifugation followed by nanoparticle tracking analysis (NTA) were utilized to quantify small EVs, while confocal laser scanning microscopy (CLSM) and image analysis characterized larger EVs. The number and size distribution of small EVs measured by NTA were unaffected by OA, but these results may be limited by the lack of hyaluronidase pre-treatment of the samples. When visualized by CLSM, the number and proportion of larger HA-containing EVs (HA–EVs) decreased in OA SF (generalized linear model, count: p = 0.024, %: p = 0.028). There was an inverse association between the OA grade and total EV count, HA–EV count, and HA–EV % (rs = – 0.264 to – 0.327, p = 0.012–0.045). The total HA concentrations were also lower in OA (generalized linear model, p = 0.002). To conclude, the present study discovered a potential SF biomarker (HA–EVs) for naturally occurring equine OA. The roles of HA–EVs in the pathogenesis of OA and their potential as a joint disease biomarker and therapeutic target warrant future studies.

Transtubular Endoscopic Posterolateral Decompression for L5-S1 Lumbar Lateral Disc Herniation.

We report a novel technique for C-arm free transtubular L5 nerve decompression under CT-based navigation to reduce the radiation hazard. This procedure is performed under general anesthesia and neuromonitoring. The patient is placed in a prone position on an operating carbon table. A navigation reference frame is placed percutaneously into the contralateral sacroiliac joint or spinous process. Then, CT scan images are obtained. After instrument registration, the L5-S1 foraminal level is confirmed with a navigated probe, and the entry point is marked. Using an approximately 2 cm skin incision, the subcutaneous tissue and muscles are dissected. The navigated first dilator is aimed at the L5-S1 Kambin's triangle, and sequential dilation is performed. The 18 mm tube is used and fixed to the frame. The bone around the Kambin's triangle is removed with a navigated burr. For lateral disc herniation, the L5 nerve root is identified and retracted, and the disc fragment is removed. The navigation-guided tubular endoscopic decompression is an effective procedure. There is no radiation hazard to the surgeon or the operating room staff.