Tibiofemoral Joint Space Research Articles

Kinematic change of the meniscus and the tibiofemoral joint space in asymptomatic volunteers using a wide bore 3T closed MRI system.

To evaluate kinematic changes in menisci and tibiofemoral joint spaces in extension and flexion using asymptomatic volunteers using a wide-bore 3-T closed MRI system. Twenty-two knees from asymptomatic volunteers were examined in knee extension and flexion using a 3-T MRI (sagittal 2D FSE T2-weighted sequence and sagittal 3D isotropic FSE proton density-weighted cube sequence). The meniscal positions, meniscal floating and flounce were evaluated. The widths of the medial and lateral tibiofemoral joint spaces and coronal tibiofemoral angles were measured. In the anteroposterior direction, meniscal extrusion was most frequently seen in the anterior horn of the medial menisci (100%) in extensions (maximum 6.04 mm). Most of the menisci moved significantly to the posterior side from extension to flexion. The anteroposterior meniscal movement was the greatest for the anterior horn of the medial meniscus and least for the posterior horn of the medial meniscus. In the mediolateral direction, meniscal extrusion was seen in 52% of the medial menisci in extensions (maximum 1.91 mm) and 29% of lateral menisci in flexions (maximum 2.36 mm). From the extension to flexion, all medial and lateral menisci moved significantly to the lateral side. Meniscal floating was frequently observed in the posterior horn of medial menisci in extension. Meniscal flounce was frequently seen in lateral menisci in flexion with a widened lateral tibiofemoral joint space gap. The coronal tibiofemoral angle showed medial wedging in flexion, but not in extension. Wide-bore 3-T closed MRI revealed significant kinematic changes in the menisci and tibiofemoral joint spaces in asymptomatic volunteers.

In vivo evaluation of the subject-specific finite element model for knee joint cartilage contact area

In this paper, we present a new validation method for subject-specific finite element (FE) modeling of the knee joint based on in vivo computed tomography (CT) and magnetic resonance imaging (MRI) data. Previously, several FE models have been developed for estimating the mechanical response of joint structures, where direct or indirect in vivo measurement is difficult or impossible. More recently, studies using MRI have provided clear visualization of the motion and deformation of the articular cartilage within the tibiofemoral (TF) joint space. Two methods have been introduced to validate in vivo subject-specific models: alignment of supine MRI with X-ray images and weight-bearing MRI. The size of the contact area between the femur and tibia was determined by computing the area of femoral cartilage that intersected the tibial cartilage. The result showed good agreement between non-weight bearing image aligned with X-ray and weight-bearing MRI images. This study may help to better define the relative importance of modeling validations for the development of subject-specific models.

A Study to Analyze Relationship Between Radiological Morphometric Measurements of Knee Joint And Symptomatology of Osteoarthritis

Objectives To study the morphometric radiological measurements of knee joint of patients suffering from osteoarthritis. To study the correlation, if any, between the measurements and severity of symptoms (disability). Materials and Methods The cross sectional study comprised of 30 subjects suffering from osteoarthritis. Knee joint roentgenograms (both AP and lateral views) of these patients and 30 age and sex matched subjects attending the OPD for other ailments to serve as controls were taken.The patients were asked to grade pain from 0-4 in: Squatting, Getting up from sitting position,Sitting cross legged 0—indicating no discomfort or pain, to 4—indicating most severe discomfort or pain. Radiological measurements taken included: Average joint space width Articulate angle Medial tibiofemoral space Lateral tibiofemoral space Results The values of average joint space width, and medial and lateral tibio-femoral joint space was found to be significant in patients with Osteo arthritis when compared to controls Conclusion In our study, the morphometric measurements (average joint space width, tibial anatomical axis, medial and lateral tibiofemoral joint space and articulate angle) in patients of knee OA were significantly reduced when compared to controls but their correlation to pain symptoms was found to be non-significant may be because the study was on a very small scale.Nevertheless the measurements done were relatively simple therefore easily reproducible and also independent of any observational error.

The relationship between lower extremity strength and function with tibiofemoral joint space width following ACL injury and surgical reconstruction

The relationship between lower extremity strength and function with tibiofemoral joint space width following ACL injury and surgical reconstruction

Test-retest reliability of tibiofemoral joint space width measurements using low-dose standing CT

Test-retest reliability of tibiofemoral joint space width measurements using low-dose standing CT

Diabetes is a risk factor for knee osteoarthritis progression

Recent studies have suggested that metabolic factors (obesity, diabetes, hypertension and dyslipidemia) and their clustering in metabolic syndrome (MetS) might be involved in the pathophysiology of knee osteoarthritis (OA). We investigated their impact on radiographic progression by an annualised measure of the joint space narrowing (JSN) of the medial tibiofemoral compartment. 559 patients older than 50 years with symptomatic knee OA were recruited for the placebo arm of the SEKOIA trial. The presence of diabetes, hypertension and dyslipidemia was determined at baseline interview. Body mass index (BMI) was calculated, obesity was considered >30 kg/m(2). MetS was defined by the sum of metabolic factors ≥ 3. Minimal medial tibiofemoral joint space on plain radiographs was measured by an automated method at baseline and then annually for up to 3 years. The mean age of patients was 62.8 [62.2-63.4] years; 392 were women. A total of 43.8% was obese, 6.6% had type 2 diabetes, 45.1% hypertension, 27.6% dyslipidemia and 13.6% MetS. Mean annualised JSN was greater for patients with type 2 diabetes than without diabetes (0.26 [-0.35 to -0.17] vs 0.14 [-0.16 to -0.12] mm; P = 0.001). This association remained significant after adjustment for sex, age, BMI, hypertension and dyslipidemia (P = 0.018). In subgroup analysis, type 2 diabetes was a significant predictor of JSN in males but not females. The other metabolic factors and MetS were not associated with annualised JSN. Type 2 diabetes was a predictor of joint space reduction in men with established knee OA. No relationships were found between MetS or other metabolic factors and radiographic progression.

Pulsed Radiofrequency of the Composite Nerve Supply to the Knee Joint as a New Technique for Relieving Osteoarthritic Pain: A Preliminary Report

We report a new technique for pulsed radiofrequency (PRF) of the entire nerve supply of the knee as an option in treating osteoarthritis (OA) of knee. We targeted both sensory and motor nerves supplying all the structures around the knee: joint, muscles, and skin to address the entire nociception and stiffness leading to peripheral and central sensitization in osteoarthritis. Ten patients with pain, stiffness, and loss of function in both knees were treated with ultrasonography (USG) guided PRF of saphenous, tibial, and common peroneal nerves along with subsartorial, peripatellar, and popliteal plexuses. USG guided PRF of the femoral nerve was also done to address the innervation of the quadriceps muscle. Assessment of pain (Numerical Rating Scale [NRS], pain DETECT, knee function [Western Ontario and McMaster Universities Osteoarthritis Index- WOMAC]) were documented pre and post PRF at 3 and 6 months. Knee radiographs (KellgrenLawrence [K-L] grading) were done before PRF and one week later. All the patients showed a sustained improvement of NRS, pain DETECT, and WOMAC at 3 and 6 months. The significant improvement of patellar position and tibio-femoral joint space was concordant with the patient’s reporting of improvement in stiffness and pain. The sustained pain relief and muscle relaxation enabled the patients to optimize physiotherapy thereby improving endurance training to include the daily activities of life. We conclude that OA knee pain is a product of neuromyopathy and that PRF of the sensory and motor nerves appeared to be a safe, effective, and minimally invasive technique. The reduction of pain and stiffness improved the knee function and probably reduced the peripheral and central sensitization. Key words: Osteoarthritis, knee pain, stiffness, knee innervation, femoral nerve supply, Hilton’s law, peripheral sensitization, pulsed radiofrequency treatment of nerves to knee joint

Progression of cartilage damage and meniscal pathology over 30 months is associated with an increase in radiographic tibiofemoral joint space narrowing in persons with knee OA – the MOST study

To determine the association of MRI-assessed worsening of tibiofemoral cartilage damage, meniscal damage, meniscal extrusion, separately and together, with progression of radiographic joint space narrowing (JSN). The Multicenter Osteoarthitis Study (MOST) Study is a cohort study of subjects with or at risk for knee osteoarthritis (OA). Knees with radiographic OA Kellgren-Lawrence grade 2 at baseline and with baseline and 30-month 1.0 T MRIs were selected for reading using the WORMS system for cartilage damage, meniscal damage, and meniscal extrusion. The association of worsening of cartilage damage, meniscal damage, and/or meniscal extrusion with increases in the JSN was performed using logistic regression. A total of 276 knees (one per subject) were included (women 68.5%, mean age 62.9 ± 7.8, mean body mass index (BMI) 30.2 ± 5.0). Worsening of each MRI feature was associated with any increase in JSN (P < 0.01). Worsening of cartilage damage was more frequently observed than worsening of meniscal damage and extrusion, and was significantly associated with both slow and fast progression of JSN. An increasing risk of JSN worsening was associated with increasing number of worsening MRI features (P for trend < 0.0001). Worsening of tibiofemoral cartilage damage, meniscal damage, and meniscal extrusion are independent predictors of JSN progression in the same compartment. Worsening of cartilage damage is more frequently observed in JSN when compared to meniscal worsening. A strong cumulative effect on JSN progression is observed for worsening of more than one MRI feature.

Is coxa valga a predictor for the severity of knee osteoarthritis? A cross-sectional study.

In the present study, we aimed to evaluate the affect of the variations in hip anatomy and pelvic geometry on the severity of knee OA. Idiopathic knee OA patients fulfilling the clinical criteria of American College of Rheumatology for OA were enrolled in the study. Several measurements regarding the hip and pelvis were performed on pelvic radiographs. Each knee was graded according to the Kellgren and Lawrence (KL) radiographic system (0-4) along with a categorization in accordance with the medial tibiofemoral joint space widths (JSW). The study group consisted of 111 subjects. The inner and outer pelvic diameters were getting wider as the JSW grade increased. Likewise, among the hip measurements, femoral head, neck and shaft diameters and hip axis lengths were linked with KL grade. There were significant differences in neck-shaft angle (NSA) between groups of JSW with a highest NSA in JSW grade 3. The optimal cut-off value for NSA in predicting the severity of knee OA was 134.4°. Furthermore, NSA beyond 134.4° was found to increase the risk of severe knee OA eightfold. Variations in pelvic geometry and hip anatomy are associated with the severity of knee OA. People with NSA of above 134.4° have eightfold increased risk of developing severe knee OA. Pelvic radiographies could be evaluated at younger ages-particularly in people with high genetic predispositions-to identify the individuals at high risk and in turn, to tailor the preventive measures to these subjects.

Recurrent Suprapatellar Fullness and Synovial Frond-like Masses on Knee MRI.

A 50-year-old male presented with recurrent effusion around the left knee joint. There was no history of trauma to the knee or recent episode of fever. On clinical examination, suprapatellar fullness with decreased range of movement was noted. However, there was no tenderness or redness of the overlying skin. There were no complaints in other joints of the body or a similar family history. He was advised X-ray of the knee joint (anteroposterior and lateral view) which showed advanced degenerative changes in the form of reduced tibiofemoral joint space, osteophyte formation with subchondral sclerosis, and cystic changes. A large suprapatellar fullness was also seen (Fig. 1). He was advised magnetic resonance imaging (MRI) to look for any synovial or intraarticular pathology (Figs. 2, 3 and 4).

The mid-term outcome of unicondylar knee arthroplasty for patients in mid-ages

Objective To evaluate the mid-term clinical outcome of unicondylar knee arthroplasty (UKA) in patients in mid-ages.Methods Nineteen cases (21 knees) with the age less than sixty were treated with UKA from April 2007 to January 2010 and were followed up.The range of motion (ROM),the Hospital for Special Surgery (HSS) knee score,the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index,Feller score,femur-tibia angle (FTA),width of lateral tibiofemoral joint space,visual analogue scale/score (VAS) and SF-36 scale were documented.Results All patients were followed up for 4 to 6.5 years (mean,5.2 years).The 5-years survival rate was 91.7％.One revision was performed due to polyethylene spacer frayed and prosthesis aseptic loosening.The polyethylene spacer was frayed in another patient,but there were no symptoms.The HSS was 88.1±6.8 at the final follow-up,which was 60.4±5.2 preoperatively.The WOMAC was 11.5±6.5 at the final follow-up,which was 42.9±5.9 preoperatively.The VAS was 1.1± 1.8 at the final follow-up,which was 6.6±0.7 preoperatively.The ROM was 121.2°± 11.1° at the final follow-up,which was 113.8°± 11.5° preoperatively.The Feller score was 25.2±6.6 at the final follow-up,which was 19.3±7.0 preoperatively.The FTA was 175.3°±2.4° at the final follow-up,which was 179.5°±3.8° preoperatively.The width of lateral tibiofemoral joint space was 6.7±0.6 mm at the final follow-up,which was 6.8±0.6 mm preoperatively.No deterioration of the laterally compartment or patellofemoral joint cartilage destruction happened.All the parameters of life quality were below the standard values excluding the BP,RE and PF.The exercise intensity was also decreased postoperatively.Conclusion The efficacy of UKA in mid-ages was satisfied and the 5-years survival rate was high. Key words: Arthroplasty, replacement, knee; Treatment outcome; Osteoarthritis

THU0210 Impact of Components of the Metabolic Syndrome on Knee Osteoarthritis Progression in the SEKOIA Study

BackgroundRecent studies have suggested that components of the metabolic syndrome might be involved in the pathophysiology of knee osteoarthritis (OA). However, their impact on joint space narrowing in patients with...

TH‐A‐18C‐02: An Electrostatic Model for Assessment of Joint Space Morphology in Cone‐Beam CT

Purpose:High‐resolution cone‐beam CT (CBCT) of the extremities presents a potentially valuable basis for image‐based biomarkers of arthritis, trauma, and risk of injury. We present a new method for 3D joint space analysis that exploits the high isotropic spatial resolution of CBCT and is sensitive to small changes in disease‐related morphology.Methods:The approach uses an “electrostatic” model in which joint surfaces (e.g., distal femur and proximal tibia) are labeled as charge densities between which the electric field is solved by approximation to the Laplace equation. The method yields a unique solution determined by the field lines across the “capacitor” and is hypothesized to be more sensitive than conventional (Sharp) scores and immune to degeneracies that limit simple distance‐along‐axis or closest‐point analysis. The algorithm was validated in CBCT phantom images and applied in two clinical scenarios: osteoarthritis (OA, change in loadbearing tibiofemoral joint space); and assessment of injury risk (correlation of 3D joint space to tibial slope).Results:Joint space maps computed from the electrostatic model were accurate to within the voxel size (0.26 mm). The method highlighted subtle regions of morphological change that would likely be missed by conventional scalar metrics. Regions of subtle cartilage erosion were well quantified, and the method confidently discriminated OA and non‐OA cohorts. 3D joint space maps correlated well with tibial slope and provide a new basis for principal component analysis of loadbearing injury risk. Runtime was less than 5 min (235×235×121 voxel subvolume in Matlab).Conclusion:A new method for joint space assessment was reported as a possible image‐based biomarker of subtle articular change. The algorithm yields accurate quantitation of the joint in a manner that is robust against operator and patient setup variation. The method shows promising initial results in ongoing trials of CBCT in osteoarthritis, rheumatoid arthritis, and injury risk assessment.Research supported by R01 and R21 grants from the National Institutes of Health, academic‐industry partnership with Carestream Health, and a grant from the US Army Natick Soldier Research, Development &amp; Engineering Center.

Susceptibility artifacts detected on 3T MRI of the knee: frequency, change over time and associations with radiographic findings: data from the Joints on Glucosamine Study

To determine the prevalence of intraarticular susceptibility artifacts and to detect longitudinal changes in the artifacts, on 3T magnetic resonance imaging (MRI) of the knee in a cohort of patients with knee pain, and to assess the association of susceptibility artifacts with radiographic intraarticular calcifications. Three hundred and forty-six knees of 177 subjects aged 35-65 were included. 3T MRI was performed at baseline and at 6 months. Baseline radiographs were assessed for presence/absence of linear/punctate calcifications within the tibiofemoral joint (TFJ) space. Corresponding MRIs were assessed for susceptibility artifacts (i.e., linear/punctate hypointensities) in the TFJ space on coronal dual-echo steady-state (DESS) sequences. Kappa statistics were applied to determine agreement between findings on baseline DESS and radiography. Changes in artifacts over time were recorded. In the medial compartment, 13 (4%) of the knees showed susceptibility artifacts at baseline. Six knees had persistent artifacts and six knees had incident artifacts at follow-up. Agreement between DESS and radiography was κ = 0.18 (-0.15, 0.51) in the medial compartment. Frequency of artifacts in the lateral compartment was low (2%). Susceptibility artifacts detected on knee MRI are not frequent, and likely correspond to vacuum phenomena as they commonly change over time and are not associated with intraarticular calcifications. Radiologists should be aware of these artifacts as they can interfere with cartilage segmentation.

In vivo deformation of articular cartilage during electrically stimulated contraction

Purpose: In vivo movement of bones comprising synovial joints has been evaluated in various ways and has been calculated theoretically to understand joint biomechanics. In order to assess joint loading and bone movements accurately, the deformation behavior of articular cartilage has been investigated in confined and unconfined compression experiments and indentation tests (references), but to date there exist no data on dynamic in vivo deformation of articular cartilage in intact joints loaded through controlled muscular contraction. The objective of this study was to measure articular cartilage deformations as a function of load in an intact joint of live animals. Methods: In order to achieve the purpose of this study, we developed a novel in vivo testing system that allows for controlled loading of mouse knees through muscular contractions and quantification of the associated, cartilage and chondrocyte deformations. Mice were fixed in a custom-built jig onto the stage of a dual photon microscope. Controlled forces of the knee extensor muscles were produced through direct muscle stimulation using indwelling fine wire electrodes and a Grass (S8800) stimulator. The medial meniscus was excised to provide a direct view of the medial tibio-femoral joint (Figure 1). Imaging of articular cartilage deformation across the entire medial compartment of the knees was performed using a Zeiss 40×0.95 NA water-immersion objective coupled with a Coherent Chameleon IR laser tuned at 780 nm for two-photon excitation. Results: Increases in muscular loading of the knee caused an increase in articular cartilage deformation (Figure 2). Fifty and 80% of the maximal muscular forces produced average peak articular cartilage strains for an 8s contraction of 10 ± 1% to 19 ± 2% respectively (Figure 2). The average overall cartilage thickness was 32 ± 2 μm on the femoral condyles. For slow increasing forces (Figure 3a), the tibio-femoral joint space initially narrowed and reached zero (i.e., the two cartilage surfaces started to touch) when muscle forces reached approximately 40% of maximal isometric values (Figure 3b). Following cartilage contact, cartilage thickness decreased in an approximately exponential manner and reached the deformation peak approximately 5s after initial force application (Figure 3c). Cartilage tissue recovered to its original shape within approximately 30s following force removal (Figure 3c). Discussions And Conclusions: The results of this study suggest that tibio-femoral contact between the articulating surfaces is only achieved with relatively high muscular forces (about 40% of maximal). This may be an artifact of the current setup where the medial meniscus was removed, and physical contact between the two articulating surfaces may occur earlier (i.e., at lower forces) if the meniscus had been left intact. This will need to be investigated further. However, the finding seems to suggest, that at least in the presence of medial meniscectomy, high forces are required to obtain physical cartilage to cartilage contact in the medial tibio-femoral compartment of the mouse knee. Another surprising feature of this work was that cartilage behaves highly visco-elastically. Specifically, peak cartilage deformation is reached much after peak muscle forces have been reached. The delay of about 3s from peak force to peak cartilage deformation suggests that in a normal cyclic movement, such as walking (loading time approximately :800ms) peak steady-state deformation corresponding to the applied force is never reached. Similarly, full cartilage thickness recovery following load removal takes approximately 20s, suggesting that deformation recovery within cyclic movements such as walking, with an unloading time of about 1s, may be neglected. Finally, peak cartilage deformation under the present conditions seems to be maximal at muscle forces of about 70% of the maximal isometric force with further deformations with higher forces not detected by our system. This begs the question of stiffness changes in cartilage with increasing loads and the mechanisms underlying extreme deformation of cartilage under very high joint loading conditions.Figure 2Articular cartilage surface do not touch below approximately 40% of maximal muscle force, then cartilage strain increases exponentially between about 40 – 70% of the maximal force, and remains almost constant beyond about 70 – 80% of maximal force (n = 6).View Large Image Figure ViewerDownload Hi-res image Download (PPT)Figure 3(a) Normalized (relative to maximum = 100%) knee extensor forces as a function of time. Muscles were stimulated for 8 seconds at a voltage and frequency producing approximately 60% and 35% of the maximal isometric force. (b) Medial tibio-femorol joint space as a function of time. Joint space decreased as muscular force increased and reached zero when force reached approximately 40% of maximum. (c) In vivo femoral cartilage thickness changes during loading with 60% of muscular force. No sign of cartilage deformation was noticed at 35% maximal force.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Association between delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) and joint space narrowing and osteophytes: a cohort study in patients with partial meniscectomy with 11 years of follow-up

To examine the association between the relaxation time (T1Gd) of delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) and grade of tibiofemoral joint space narrowing (JSN) and osteophytosis 11 years later, in a cohort of meniscectomized patients. Patients (n = 45) aged 35-50 who had undergone an arthroscopic partial medial meniscectomy 1-6 years earlier, due to degenerative meniscal tear, were examined using dGEMRIC. These patients had no cartilage changes defined as deep clefts or visible bone at the time of arthroscopy. Eleven years later (12-16 years after surgery) 34 of these subjects (76%) were evaluated by weight-bearing knee radiography, and tibiofemoral joint changes were graded according to the Osteoarthritis Research Society International Atlas. Lower T1Gd in the medial compartment was associated with higher grade of medial JSN (grade 0, 351 ms; grade 1, 386 ms; grade 2, 342 ms; grade 3, 259 ms [P for trend < 0.001]) and more osteophytosis (score 0, 371 ms; score 1, 389 ms; score 2, 354 ms; score 3, 289 ms; score 4, 265 ms; score 5, 275 ms [P for trend = 0.001]). Lower T1Gd in the lateral compartment was associated with higher grade of lateral JSN (grade 0, 436 ms; grade 1, 346 ms [P for trend = 0.026]). The current study suggests that lower T1Gd measured with dGEMRIC of medial and lateral femoral cartilage is associated with higher grade of JSN 11 years later, and medially, also with more osteophytosis.

Comparação entre o laser de baixa potência, ultrassom terapêutico e associação, na dor articular em ratos Wistar

IntroductionBoth therapeutic ultrasound as a low level laser therapy are used to control musculoskeletal pain, despite controversy about its effects, yet the literature is poor and also presents conflicting results on possible cumulative effects of techniques association. The aim was to compare the antinociceptive effects of low level laser therapy, therapeutic ultrasound and the association. Methods24 Wistar rats were divided into: GPL – induction of hyperesthesia in the right knee, and untreated; GUS – treated with therapeutic ultrasound (1MHz, 0.4W/cm2) GL – low intensity laser (830nm, 8J/cm2); GL+US – treated with both techniques. To produce the hyperesthesia 100μl of 5% formalin solution were injected into the tibiofemoral joint space, which was assessed by von Frey filament digital before (EV1), 15 (EV2), 30 (EV3) and 60 (EV4) minutes after induction. ResultsIn comparison within groups, for the withdrawal threshold when the filament was applied to the knee, the back to baseline was observed only for GUS. Comparisons between groups were not different in EV3, and GL was higher than GPL. In EV4 the three groups effectively treated were higher than placebo. On withdrawal threshold on the plantar surface, GL showed return to baseline values already in EV3, and GUS and GL+US returned in EV4. Comparing the groups in EV3 there was a significantly lower threshold to compare GPL with GL and GUS (p <0.05), and there was only EV4 differences when comparing GPL with GUS. ConclusionBoth modalities showed antinociceptive effects.

Comparison of low level laser, ultrasonic therapy and association in joint pain in Wistar rats

IntroductionBoth therapeutic ultrasound as a low level laser therapy are used to control musculoskeletal pain, despite controversy about its effects, yet the literature is poor and also presents conflicting results on possible cumulative effects of techniques association. The aim was to compare the antinociceptive effects of low level laser therapy, therapeutic ultrasound and the association. Methods24 Wistar rats were divided into: GPL – induction of hyperesthesia in the right knee, and untreated; GUS – treated with therapeutic ultrasound (1MHz, 0.4W / cm2) GL – low intensity laser (830nm, 8J/cm2); GL+US – treated with both techniques. To produce the hyperesthesia 100μl of 5% formalin solution were injected into the tibiofemoral joint space, which was assessed by von Frey filament digital before (EV1), 15 (EV2), 30 (EV3) and 60 (EV4) minutes after induction. ResultsIn comparison within groups, for the withdrawal threshold when the filament was applied to the knee, the back to baseline was observed only for GUS. Comparisons between groups were not different in EV3, and GL was higher than GPL. In EV4 the three groups effectively treated were higher than placebo. On withdrawal threshold on the plantar surface, GL showed return to baseline values already in EV3, and GUS and GL+US returned in EV4. Comparing the groups in EV3 there was a significantly lower threshold to compare GPL with GL and GUS (p <0.05), and there was only EV4 differences when comparing GPL with GUS. ConclusionBoth modalities showed antinociceptive effects.

Relationship Between Isokinetic Strength and Tibiofemoral Joint Space Width Changes After Anterior Cruciate Ligament Reconstruction

Background: It has been hypothesized that quadriceps muscle weakness is directly associated with the onset and progression of posttraumatic osteoarthritis after anterior cruciate ligament (ACL) injury and reconstruction (ACLR). This relationship, however, has not been studied with a prospective approach that includes the use of tibiofemoral joint space width difference (JSW-D) measurements to characterize the onset of posttraumatic osteoarthritis before the clinical manifestation of the disease. Purpose: To assess the relationship between thigh muscle strength and JSW-D at presurgery baseline and at 1- and 4-year follow-up after ACLR compared with healthy, noninjured participants of similar sex, age, body mass index, and activity level. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 39 unilateral ACL-injured patients and 32 healthy controls were followed prospectively. During each follow-up, JSW, isokinetic knee strength, single-legged hop, and clinical- and patient-oriented outcomes were assessed. At final follow-up, ACL-injured participants who had JSW-D values (considered as the injured minus normal knee) that were less than the 95% confidence interval of controls were considered to be in the ACLR-narrow group, while those with JSW-D values that fell within the confidence intervals were in the ACLR-normal group. Relationships were evaluated between ACLR groups and controls via multilevel regression, as well as Kruskal-Wallis tests for between-group comparisons at 4-year follow-up. Results: At 4-year follow-up, 30 participants (79%) were in the ACLR-normal group and 8 (21%) were in the ACLR-narrow group. At baseline, the extension, flexion, and extension/flexion ratio strength values for both ACLR groups were significantly lower than those of controls (P ≤ .05), while the ACLR-narrow group had significantly lower extension strength at 60 and 180 deg/s (P = .04 and .03, respectively), as well as extension/flexion ratio at 60 deg/s (P = .04) in comparison with the ACL-normal group. At 4-year follow-up, 60 deg/s extension strength deficits persisted in the ACLR-narrow group compared with controls and ACLR-normal participants (P = .01 and .04, respectively). Flexion strength at 180 and 300 deg/s was also significantly lower in the ACLR-narrow group compared with ACLR-normal (P = .02 and .04, respectively), as was single-legged hop distance (P = .04). Conclusion: Strength deficits present within months after ACL injury and persist through 4 years after ACLR in participants with significantly narrowed JSW-D, compared with ACLR participants with normal JSW-D and controls. This study revealed a significant relationship between quadriceps strength loss that occurred soon after injury and JSW narrowing.

Soft drink intake and progression of radiographic knee osteoarthritis: data from the osteoarthritis initiative

ObjectivesWe examine the prospective association of soft drink consumption with radiographic progression of knee osteoarthritis (OA).DesignProspective cohort study.SettingThis study used data from the osteoarthritis initiative (OAI).ParticipantsIn OAI, 2149 participants with...