Talar Articular Cartilage Research Articles

A Traumatic Impact Immediately Changes the Mechanical Properties of Articular Cartilage.

To investigate whether and how a single traumatic impact changes the mechanical properties of talar articular cartilage. A marble was placed on the joint surface and a weight was dropped on both medial and lateral caprine talus to create a well-defined single focal impact. The mechanical properties of intact and impacted talar cartilage were measured with a micro-indenter. Elastic (storage) and viscous (loss) moduli were determined by oscillatory ramp and dynamic mechanical analysis protocols. We found significant differences between ankles and within the same ankle joint, with the medial talus having significantly higher storage- and loss moduli than the lateral talus. The storage- and loss moduli of intact articular cartilage increased with greater indentation depths. However, postimpact the storage- and loss moduli were significantly and consistently lower in all specimens indicating immediate posttraumatic damage. The deeper regions of talar cartilage were less affected by the impact than the more superficial regions. A single traumatic impact results in an immediate and significant decrease of storage- and loss moduli. Further research must focus on the development of non- or minimally invasive diagnostic tools to address the exact microdamage caused by the impact. We speculate that the traumatic impact damaged the collagen fibers that confine the water-binding proteoglycans and thereby decreasing the hydrostatic pressure of cartilage. As part of the treatment directly after a trauma, one could imagine a reduction or restriction of peak loads to prevent the progression of the cascade towards PTOA of the ankle joint.

Chondroprotective Effects of Periodontal Ligament-Derived Stem Cells Conditioned Medium on Articular Cartilage After Impact Injury.

Paracrine factors secreted in the conditioned media (CMs) of periodontal ligament-derived stem cells (PDLSCs) have been shown to downregulate inflammatory effects of interleukin (IL)-1β on chondrocytes wherein milk fat globule-epidermal growth factor 8 (MFG-E8) is one of the PDLSCs' highly secretory proteins. Therefore, the objective of this study was to investigate the ability of PDLSC CMs and MFG-E8 to reduce the inflammatory effects of impact injury on porcine talar articular cartilage (AC) and IL-1β on chondrocytes, respectively. Stem cells were isolated from human periodontal ligaments. The MFG-E8 content in CM collected at 5% and 20% oxygen was measured by ELISA assay and compared across subcultures and donors. AC samples were divided into three groups: control, impact, and impact+CM. Chondrocytes were isolated from pig knees and were divided into three groups: control, IL-1β, and IL-1β+MFG-E8. Gene expression data were analyzed by reverse transcription-polymerase chain reaction. It was found that impact load and IL-1β treatment upregulated IL-1β, TNF-α, ADAMTS-4, and ADAMTS-5 gene expression in AC and chondrocytes, respectively. PDLSCs-CM prevented the upregulation of all four genes due to impact, whereas MFG-E8 prevented upregulation of IL-1β, ADAMTS-4, and ADAMTS-5 in chondrocytes, but it did not prevent TNF-α upregulation. There were no significant differences in MFG-E8 content in CM among oxygen levels, passage numbers, or donors. The findings suggested that MFG-E8 is an effective anti-inflammatory agent contributing to the chondroprotective effects of PDLSCs-CM on acutely injured AC. Thus, introducing PDLSCs-CM to sites of acute traumatic AC injury could prevent the development of post-traumatic osteoarthritis.

Nanohydroxyapatite Hydrogel Can Promote the Proliferation and Migration of Chondrocytes and Better Repair Talar Articular Cartilage.

As an important load-bearing part of the body, joints are prone to articular cartilage degradation during exercise, resulting in joint pain, swelling, and deformity, which has an adverse impact on patients' life quality and social medical security. Therefore, this study aims to test an effective biopolymer scaffold in promoting the growth of chondrocytes in talus. Hydrogel (Gel)-nanohydroxyapatite (nHA) was invented as a new type of biopolymer scaffold for osteoarthritis treatment in this research. To detect the effects of Gel-nHA on guidance, cartilage matrix secretion, mineralization, proliferation, and migration of chondrocyte, we cultured chondrocytes to study the biological properties of nHA. It was found that Gel could guide chondrocytes to permeate and migrate, so it could be used as acellular matrix scaffolds for chondrocyte regeneration. In addition, nHA could stimulate chondrocytes to secrete cartilage matrix, such as type II collagen and mucopolysaccharide (GAGs). At the same time, nHA help to induce chondrocyte mineralization and stimulate the secretion of type X collagen, so as to better maintain the integrity of bone cartilage interface. In Gel-nHA, chondrocyte viability could be better maintained, and the proliferation and migration of chondrocytes could be better promoted, so as to better repair the articular cartilage of talus. Therefore, the Gel-nHA scaffold is expected to become an effective method for repairing talus cartilage in the future.

Plantar pressure profile during walking is associated with talar cartilage characteristics in individuals with chronic ankle instability

BackgroundIndividuals with chronic ankle instability typically present with abnormal gait patterns favoring the lateral foot. This gait pattern may alter cartilage stress potentially increasing the risk of osteoarthritis development, thus exploring this relationship may provide insights for early interventions. The purpose of this study was to examine the relationship gait biomechanics and talar articular cartilage characteristics. MethodsTalar articular cartilage was assessed with ultrasound at rest and after walking for 30-min in twenty-five adults (14 females, 22.6 ± 3.12 years, 168.12 ± 9.83 cm, 76.00 ± 15.47 kg) with chronic ankle instability. Cartilage was segmented into Total, Medial, and Lateral regions. During the 30-min walking period, plantar pressure of the entire foot was recorded every 5-min and condensed to create a biomechanical loading pattern and center of pressure gait line. Relationships between resting cartilage thickness and echo intensity, changes in thickness and echo intensity, and plantar pressure profiles were assessed with correlation coefficients. FindingsThere was a significant relationship between plantar pressure in the lateral forefoot and medial talar cartilage deformation (r = 0.408, p < .05). Early stance center of pressure was correlated with deformation in the total (r = 0.439–0.524) and lateral (r = 0.443–0.550) regions (p < .05). There were no significant correlations between echo intensity and biomechanics. InterpretationThis study contributes to the growing evidence that talar cartilage strain patterns are associated with biomechanics during walking. Further validation is needed to determine a causal relationship between biomechanics and ultrasound cartilage characteristics after ankle sprains. In addition, research should continue determining the utility of ultrasound to monitor joint health after musculoskeletal injuries.

Reliability of Manually Segmenting T1ρ Magnetic Resonance Sequences of Talar Articular Cartilage.

Quantifying early posttraumatic ankle osteoarthritis pathogenesis using compositional magnetic resonance (MR) imaging sequences is becoming more common. These MR sequences are often manually segmented to isolate the cartilage of interest before cartilage compositional values (eg,T1ρ or T2) are quantified. However, limited information is available regarding the reliability and reproducibility of manual segmentation for the entire talar dome. The purpose of this study was to determine the intraobserver and interobserver reliability of manually segmenting T1ρ MR sequences of the entire talar dome and 4 subregions of interest. Descriptive observational study. Laboratory. Ten uninjured healthy individuals (4M and 6F: 21.40 [3.03]y, 170.00 [7.93]cm, 71.03 [14.97]kg) participated. None. Two investigators manually segmented 10 T1ρ ankle MR sequences using ITK-SNAP software to calculate T1ρ mean relaxation times and cartilage volumes. Each observer repeated the segmentation twice, with segmentations separated by 1 month. Intraobserver and interobserver reliability was determined using intraclass correlation coefficients (ICCs) with 95% confidence intervals and root mean square coefficient of variations (RMSCVs). For T1ρ relaxation time, intraobserver (ICC = .994-.997, RMSCV = 1.31%-1.51%) and interobserver reliability (ICC = .990, RMSCV = 2.36%) was excellent for the overall talar dome. Excellent intraobserver (ICC = .975-.980, RMSCV = 3.88%-4.59%) and excellent interobserver reliability (ICC = .970, RMSCV = 5.13%) was noted for overall talar cartilage volume. The results demonstrate that manual segmentation of the entire talar dome from a T1ρ MR is reliable and repeatable.

Talar-Cartilage Deformation and Spatiotemporal Gait Patterns in Individuals With and Those Without Chronic Ankle Instability.

Individuals with chronic ankle instability (CAI) present with alterations in the compositional structure of their talar articular cartilage. These alterations likely influence how the talar cartilage responds to the loading associated with activities of daily living, such as walking. Ultrasonography has emerged as an alternative imaging modality for assessing the amount of cartilage deformation in response to loading because it is clinically accessible and cost effective for routine measurements. To (1) compare talar-cartilage deformation in response to a standardized exercise protocol between those with and those without CAI and (2) examine the association between spatiotemporal walking gait parameters and cartilage deformation. Case-control study. Research laboratory. A volunteer sample of 24 participants with self-reported CAI (age = 23.2 ± 3.9 years, body mass index [BMI] = 25.1 ± 3.7 kg/m2) and 24 uninjured controls (age = 24.3 ± 2.9 years, BMI = 22.9 ± 2.8 kg/m2). Spatiotemporal walking gait was first assessed from 5 self-selected trials using an electronic walkway with data sampled at 120 Hz. An 8- to 13-MHz linear-array ultrasound transducer placed transversely in line with the medial and lateral malleoli captured 3 images before and after a standardized loading protocol consisting of 30 single- and double-limb squats, 2-minute single-limb balance, and 10 single-legged drops from a 40-cm-height box. After controlling for BMI, we found that the participants with CAI had greater deformation than the uninjured control participants (P = .034). No other between-groups differences were observed (P values > .05). No significant partial correlations were noted between talar-cartilage deformation and spatiotemporal gait parameters when controlling for BMI (P > .05). Individuals with CAI had greater talar-cartilage deformation in response to a standardized exercise protocol than control individuals. The amount of talar-cartilage deformation was not associated with the spatiotemporal walking gait.

Decreased Physical Activity Levels Relates To Ligament Thickness After Injury

PURPOSE: To examine thickness of the anterior talofibular ligament (ATFL) and if that thickness relates to physical activity levels one year after an ankle sprain. METHODS: Twenty college students (8 males and 12 females, age = 21.2 ± 2.4 yr., mass = 80.9 ± 21.6 kg, ht = 173.3 ± 10.6 cm) with an acute LAS and 20 healthy matched controls (8 males and 12 females, age = 21.9 ± 2.8 yr., mass = 79.1 ± 20.2 kg, ht = 172.5 ± 9.8 cm) participated in the study. ATFL thickness was measured with a LOGIQ Book (GE Healthcare, Waukesha, WI) diagnostic ultrasound. The examiner orientated the probe to view the cross sectional view of the lateral malleolus and the lateral talar articular surface cartilage and the neck of the talus. Measurements of ATFL thickness were made using ImageJ software (National Institutes of Health, Bethesda, MD). Thickness of the ATFL was measured at the midpoint of the ligament between the attachments of the lateral malleolus and talus. The main outcome measures were the thickness of the ATFL (mm) at 3 days post LAS and 1 year post LAS, and physical activity levels as measured by the IPAQ and NASA physical activity scales. RESULTS: There was a significant relationship between ATFL thickness and both the IPAQ and NASA physical activity scales. As ligament thickness increased, “average time spent performing vigorous physical activity” significantly decreased (p = .04, r2 = -.86) and “average time spent performing moderate physical activity” (p = .02, r2 = -.84) one year after injury. Subjects with a LAS also had a significant relationship with time spent walking (p = .01, r2 = -.92), and days per week where they pursued vigorous activity (p = .02, r2 = -.81) or moderate activity (p = .04 r2 = -.85) one year after their sprain. As ligament thickness increased, overall subjective physical activity scores significantly decreased. CONCLUSIONS: One year after a LAS subjects had a significant relationship with ATFL thickness and activity levels. The changes in ATFL morphology may lead to the decreased physical activity levels due to the feeling of the ankle being unstable. Future research needs to focus on early interventions to ensure proper ligament healing occurs to restore joint function after an ankle sprain.

Sufficient Cartilage for Most Talar Articular Defects Can Be Harvested From the Non–Loadbearing Talus: A Cadaveric Analysis

PurposeTo assess the quantity of morselized cartilage that can be harvested from the non–load-bearing portion of the talus for immediate reimplantation.MethodsNon–load-bearing talar cartilage was harvested from 5 cadaveric specimens using a standard arthroscopic approach. Cartilage was separated from the talus in maximum dorsiflexion at the junction of the talar head and neck, grasped, and morselized into a graft using a cartilage particulator. The volume of reclaimed cartilage was measured, and the extrapolated area of coverage was compared to average osteochondral lesions of the talus previously reported.ResultsThe total yield of cartilage graft following processing that was obtained from 5 ankle joints ranged from 0.3 mL to 2.1 mL with a mean volume of 1.3 ± 0.7 mL, yielding a theoretical 13.2 ± 7.1 cm2 coverage with a 1-mm monolayer. While the average size of osteochondral lesions of the talus is difficult to estimate, they may range from 0.5 cm2 to 3.7 cm2 according to the literature.ConclusionsThis study validated that it is possible to harvest sufficient amount of cartilage for an autologous morselized cartilage graft via a single-stage, single-site surgical and processing technique to address most talar articular cartilage defects.Clinical RelevanceParticulated cartilage autografts have shown promise in surgical management of cartilage defects. A single-site, single-staged procedure that uses a patient’s autologous talar cartilage from the same joint has the potential to reduce morbidity associated with multiple surgical sites, multistaged procedure, or nonautologous tissue in ankle surgery.

A Systematic Review of Fresh Osteochondral Allograft Transplantation for Osteochondral Lesions of the Talus

Category:AnkleIntroduction/Purpose:The term osteochondral lesion of the talus (OLT) refers to any pathology of the talar articular cartilage and corresponding subchondral bone. In general, OLTs can pose a formidable treatment challenge to the orthopaedic surgeon due to the poor intrinsic ability of cartilage to heal as well as the tenuous vascular supply to the talus. Although many treatment options exist, including microfracture, retrograde drilling, autologous chondrocyte implantation (ACI), and osteochondral autograft transfer system (OATS) these options may be inadequate to treat large cartilage lesions. Osteochondral allografts have demonstrated promise as the primary treatment for OLTs with substantial cartilage and bone involvement. To our knowledge, this is the first systematic review of outcomes after fresh osteochondral allograft transplantation for OLTs.Methods:PudMed, the Cochrane Central Register of Controlled Trials, EMBASE, and Medline were searched using PRISMA guidelines. Studies that evaluated outcomes in adult patients after fresh osteochondral allograft transplantation for chondral defects of the talus were included. Operative results, according to standardized scoring systems, such as the AOFAS Ankle/Hindfoot scale and the Visual Analog Scale were compared across various studies. The methodological quality of the included studies was assessed using the Coleman methodology score.Results:There were a total of 12 eligible studies reporting on 191 patients with OLTs with an average follow-up of 56.8 months (range 6-240). The mean age was 37.5 (range 17-74) years and the overall graft survival rate was 86.6%. The AOFAS Ankle/Hindfoot score was obtained pre- and postoperatively in 6 of the 12 studies and had significant improvements in each (P<0.05). Similarly, the VAS pain score was evaluated in 5 of the 12 studies and showed significant decreases (P<0.05) from pre- to postoperatively with an aggregate mean preoperative VAS score of 7.3 and an aggregate postoperative value of 2.6. The reported short-term complication rate was 0%. The overall failure rate was 13.4% and 21.6% percent of patients had subsequent procedures.Conclusion:The treatment of osteochondral lesions of the talus remains a challenge to orthopaedic surgeons. From this systematic review, one can conclude that osteochondral allograft transplantation for osteochondral lesions of the talus results in predictably favorable outcomes with an impressive graft survival rate and high satisfaction rates at intermediate follow-up.

Osteochondral lesion of talus with gout tophi deposition: A case report

BACKGROUNDOsteochondral lesion of talus is a broad term used to describe an injury or abnormality of the talar articular cartilage and adjacent bone. It arises from diverse causes, and although trauma is implicated in many cases, it does not account for the etiology of every lesion. Gout is a chronic arthritic disease caused by excess levels of uric acid in blood. Intraosseous deposition of monosodium urate in the clavicle, femur, patella and calcaneus was reported previously. Gout is common disease but rare at a young age, especially during teenage years. Osteochondral lesion caused by intra-articular gouty invasion is very rare.CASE SUMMARYWe encountered a rare case of a 16-year-old male who has osteochondral lesion of the talus (OLT) with gout. He had fluctuating pain for more than 2 years. We could see intra-articular tophi with magnetic resonance image (MRI) and arthroscopy. We performed arthroscopic exploration, debridement and microfracture. Symptoms were resolved after operation, and bony coverage at the lesion was seen on postoperative images. We had checked image and uric acid levels for 18 mo.CONCLUSIONIt is rare to see OLT with gouty tophi in young adults. While it is challenging, the accuracy of diagnosis can be improved through history taking, MRI and arthroscopy.

Analysis of Clinical Value of Weight-Bearing Magnetic Resonance Diagnosis of Ankle Ligament Sports Injury

Observe and analyze the effect of weighted magnetic resonance imaging in the diagnosis of ankle ligament sports injury. Methods: A total of 50 patients with ankle ligament sports injuries were recruited as research subjects to conduct clinical diagnostic research. After admission, the patient first underwent MRI diagnosis of ankle joint ligament sports injury and then received surgical treatment. Based on the results of surgical treatment, the diagnostic effect of weighted magnetic resonance imaging and the detection of concurrent injuries were compared. After surgery, a total of 24 cases of ankle ligament contusion were confirmed in 50 patients, 19 cases were partially ruptured, 7 cases were completely ruptured, and 26 cases had joint effusion, tendon injuries in 17 cases, fractures in 8 cases, and talar articular cartilage lesions in 19 cases. After comparison, there was no significant difference between the results of weight-bearing magnetic resonance diagnosis and the detection rate of concurrent injuries compared with the surgical results, P> 0.05. Conclusion: The application of weight-bearing magnetic resonance imaging in the diagnosis of ankle ligament sports injury can effectively diagnose the patient's ligament injury and the type of combined injury, and has significant clinical application value.

Regional Genetic Responses of Porcine Talar Articular Cartilage to Impact Injury

Category:Ankle ArthritisIntroduction/Purpose:The ankle is at greatest risk for post-traumatic osteoarthritis (PTOA) in comparison to the hip or knee. Adaptive changes to the cartilaginous topography may be a marker for where cartilage damage poses the greatest risk of development of osteoarthritis. The objective of this study was to elucidate the mechanism of PTOA by analyzing the changes in regional genetic expression of inflammatory markers after impact injury in an ex-vivo porcine model.Methods:Talus bones were recovered from 5 porcine ankles. A drop tower was used to induce injury by dropping a 1000 g weight from a height of 15 cm on the talus. Following the injury the bone was cultured for 24 hours. Four 6-mm cartilage plugs were harvested from the inferior aspect of each talus bone and a small slice of each plug was used for cell imaging. The remaining cartilage plugs were flash frozen with liquid nitrogen and stored at -80°C for ribonucleic acid (RNA) extraction and analysis of gene expression. Expression of inflammatory and catabolic genes (IL1-ß, TNF-a, ADAMTS-5, ADAMTS-4, MMP-3 and MMP-13) was compared among the samples obtained from the non-impacted and impacted sites of the anterior and posterior regions. Student t-test was performed to examine the differences between the control (non-impact) and impacted samples from each region and between the control samples from the anterior and posterior regions.Results:The current porcine impact model demonstrated significant up-regulation of several inflammatory cytokines and metalloproteinases by impact force. Among the genes tested, TNF-a, ADAMTS-4, and MMP-3 showed increased expression at impact sites (p<0.05) compared to non-impact sites in the posterior region (Figure 1) whereas no differences were found in the anterior region. Interestingly, the non-impacted samples in the anterior region exhibited significantly higher expression of TNF-a, ADAMTS-4, MMP-3 and ADAMTS-5 than those of the posterior region (p<0.05).Conclusion:The results of the current ex-vivo porcine impact study demonstrate significant up-regulation of inflammatory and catabolic genes 24 hours after porcine talus bone impaction. These findings highlight the relevance of regional differences in post- traumatic ankle inflammation; the posterior region of porcine talar articular cartilage demonstrated increased sensitivity in response to injury. The anterior region illustrated greater resistance to injury, showing less gene up-regulation compared to the posterior region of the same ankle. These findings suggest that location of cartilage injury may play a crucial role in the development of inflammatory response, chondrocyte apoptosis, and subsequent osteoarthritis of the ankle.

Comparison of talar cartilage thickness between those with and without chronic ankle instability: a ultrasonography study

Purpose: Chronic ankle instability (CAI) has been linked with the development of ankle post-traumatic osteoarthritis. Individuals with CAI demonstrate early degenerative changes in talar cartilage composition using advanced MR techniques. However, MR-based imaging techniques are not clinically accessible or cost effective. Ultrasonography (US) has emerged as an alternative to MR to assess femoral cartilage morphology, but it remains unknown if US is able to assess between group differences in cartilage thickness at ankle joint. Therefore, the purpose of this study is to determine if US measures of talar cartilage thickness at rest differ between those with CAI and uninjured healthy individuals. Methods: Fifteen individuals with CAI (age: 21.2±1.8 years, height: 1.7±.8m, mass: 67.0±7.7kg) and fifteen uninjured controls (age: 21.0±2.5 years, height: 1.7±.8m, weight: 69.6±13.2kg) volunteered to participate. As recommended by the International Ankle Consortium, individuals with CAI demonstrated a history of at least one lateral ankle sprain and at least two episodes of giving way within the past 6 months; an Identification of Functional Ankle Instability (IdFAI) >11, a Foot and Ankle Ability Measure Activities of Daily Living subscale (FAAM-ADL) < 90%, and a FAAM-Sport subscale (FAAM-S) < 80%. Controls demonstrated no history of ankle sprains and giving way episodes; an IdFAI of < 11, a FAAM-ADL of ≥98%, a FAAM-S of ≥98%. Relative to the controls, CAI participants had a history of multiple lateral ankle sprains (4.0±2.1 vs. 0.0±0.0 sprains), multiple giving way episodes within the past 6 months (6.6±5.1 vs. 0.0±0.0 episodes), higher IdFAI scores (22.9±2.8 vs. 0.1±0.5), and greater limitations in self-reported function based on the FAAM-ADL (85.9±9.7% vs. 100.0±0.0%) and FAAM-S (68.4±20.6% vs. 100.0±0.0%). The US images of talar cartilage thickness were acquired using a LOGIQe system with a 12 MHz linear probe after unloading the cartilage for 30 minutes. For US imaging, participants were positioned supine with the knee in 90 degrees of flexion and the ankle plantar flexed so that the foot was flat on the support surface. The US probe was placed transversely in line with the medial and lateral malleolus and rotated to maximize reflection of the talar articular cartilage surface. Talar cartilage images were manually segmented using ImageJ software to identify the medial, lateral, and overall cross-sectional area (mm2). Cross-sectional area was then normalized to the length of the cartilage-bone interface to obtain an average thickness (mm). Average thickness in each region of interest (i.e. medial, lateral, overall) were compared between CAI patients and healthy controls using independent sample t-tests and an a priori alpha level of 0.05. Results: The CAI and controls groups were similar in terms of their age, height, and weight (p≥0.433). Measures of injury history and self-reported function differed between the groups (p<0.001) as expected. There is no significant difference between the CAI and control groups in the medial (CAI: 0.394±0.089mm, control: 0.435±0.112mm, p=0.276), lateral (CAI: 0.441±0.131mm, control: 0.458±0.117mm, p=0.717), or overall (CAI: 0.427±0.094mm, control: 0.450±0.083mm, p=0.493) regions of interest. Conclusions: Previous studies showed that CAI patients had worse compositional changes (i.e. higher T1rho and T2 mapping relaxation times) of the talar cartilage compared to healthy individuals without morphological degradation (i.e. no decline in cartilage volume). Our results indicate that US thickness measures at rest did not differ between CAI and control groups. This finding supports the existing literature that illustrates no morphological changes in talar cartilage in the early stage of joint degeneration. US appears to be a feasible method for evaluating ankle cartilage morphology, but future research is needed to determine if US based measures of cartilage deformation or resiliency following a standardized loading protocol, which may provide information regarding cartilage composition, differ between CAI and uninjured individuals.

T1ρ MRI of the talar articular cartilage is increased in those with chronic ankle instability

To determine if individuals with chronic ankle instability (CAI) demonstrate different talar cartilage T1ρ relaxation times compared to uninjured controls. Fifteen CAI (21.13±1.81 years, 4.00±2.07 previous ankle sprains) and fifteen controls (21.07±2.55 years, no previous ankle sprains) participated. CAI inclusion criteria was in accordance with the International Ankle Consortium guidelines. Greater T1ρ relaxation times were interpreted as greater degenerative changes. Participants were non-weight bearing for 30-minutes prior to scanning to unload the cartilage. Voxel by voxel T1ρ relaxation times were calculated from a five image sequence. Segmentation of the talar cartilage was performed manually using ITK-SNAP software. T1ρ relaxation time means and variability across the entire talus and in the anteromeidal, anterolateral, posteromedial, and posterolateral regions of interest (ROIs) were compared between groups using mean differences and effect sizes (ES) with their corresponding 95% confidence intervals (95%CI). Individuals with CAI demonstrated higher T1ρ relaxation times (mean±standard deviation) across the entire talus (CAI: 65.97±10.45ms, Control: 58.84±7.68ms; ES=0.76, 95%CI=0.02-1.50), in the anterolateral (ES=1.00, 95%CI=0.24-1.48), posteromedial (ES=0.74, 95%CI=0.01-1.49), and posterolateral region of interest (ES=3.84, 95%CI=2.63-5.04). The T1ρ relaxation time variability (mean±standard deviation) also differed across the overall talus (CAI: 32.78±4.06ms, Control: 28.23±4.45ms; ES=1.04, 95%CI=0.28-1.80), in the anteriolateral, (ES=1.07, 95%CI=0.31, 1.84) and posteriolateral (ES=1.00, 95%CI=0.24-1.75) ROIs. Individuals with CAI demonstrate greater T1ρ relaxation times and higher T1ρ variability compared to uninjured controls. This finding supports the existing literature illustrating early degenerative joint tissue changes consistent with early onset posttraumatic osteoarthritis in individuals with CAI.

Comparative Outcomes for the Treatment of Articular Cartilage Lesions in the Ankle With a DeNovo NT Natural Tissue Graft: Open Versus Arthroscopic Treatment.

Background:The treatment of osteochondral lesions of the talus (OLTs) with a juvenile cartilage allograft is a relatively new procedure. Although other treatment options exist for large OLTs, the potential advantage of a particulated juvenile allograft is the ability to perform the procedure arthroscopically or through a minimal approach. No previous studies have looked at the results of an arthroscopic approach, nor have any compared an arthroscopic technique with an open approach.Purpose:To compare the outcomes of an arthroscopic transfer technique with the previously published open technique.Study Design:Cohort study; Level of evidence, 3.Methods:A total of 34 patients (mean age, 33 years) underwent treatment of talar cartilage lesions with a DeNovo NT Natural Tissue Graft. Of these treatments, 20 were performed arthroscopically and 14 were performed with open arthrotomy. There was no statistically significant difference between the groups with respect to age, lesion width, lesion depth, lesion length, or operative time. The mean lesion area was 107 mm2. The scores from 6 different validated outcome measures were recorded for patients in each group preoperatively and subsequently at 6 months, 1 year, 18 months, and 2 years.Results:Comparing outcome scores at each time point to baseline, there were no statistically significant postoperative differences found between open and arthroscopic approaches with regard to the visual analog scale (VAS) for pain (P = .09), American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale (P = .17), Foot and Ankle Ability Measure (FAAM)–sports subscale (P = .73), Short Form–12 (SF-12) physical health summary (P = .85), SF-12 mental health summary (P = .91), or FAAM–activities of daily living subscale (P = .76).Conclusion:The treatment of talar articular cartilage lesions with a DeNovo NT Natural Tissue Graft demonstrated no significant differences in outcome at 2 years regardless of whether the graft was inserted with an arthroscopic or open technique.Clinical Relevance:Our analysis demonstrated no significant difference between an arthroscopic versus open approach at any time point for the first 2 years after implantation of a juvenile particulated cartilage allograft for large OLTs. With that said, both groups demonstrated improvement from baseline. These findings indicate that surgeons with different levels of comfort utilizing arthroscopic techniques can offer this treatment modality to their patients without altering their planned surgical approach. In addition, this will be particularly helpful in counseling patients for surgery when the extent of the defect will be evaluated intraoperatively. Patients can be counseled that they will likely have the same incisions regardless of whether they require debridement, microfracture, or implantation of a particulated allograft.

Particulated Autograft Cartilage Implantation for the Treatment of Osteochondral Lesions of the Talus: A Novel Technique.

Level V.

Lower proteoglycan density within the talar articular cartilage is associated with worse postural control in individuals with chronic ankle instability

Lower proteoglycan density within the talar articular cartilage is associated with worse postural control in individuals with chronic ankle instability

Proteoglycan density of the talar articular cartilage is reduced in those with chronic ankle instability

Purpose: Clear links have been made between both lateral ankle sprains and chronic ankle instability (CAI) and the development of ankle post-traumatic osteoarthritis (PTOA). Current visualization techniques such as arthroscopy and standard MRI are ineffective at quantifying early degenerative changes to the talar articular cartilage. The most promising approaches for slowing ankle PTOA progression include early conservative interventions to restore appropriate joint biomechanics. Thus, identifying visualization techniques sensitive to early degenerative changes of the talar articular cartilage is needed. Therefore, the purpose of this investigation is to determine if CAI patients have lower proteoglycan density in their talar cartilage compared to uninjured controls as measured by T1ρ MRI. Methods: Fifteen CAI (age: 21.2 ± 1.8 years, height: 1.7 ± .8 m, mass: 67.0 ± 7.7 kg) and fifteen controls (age: 21.0 ± 2.5 years, height: 1.7 ± .8 m, weight: 69.6 ± 13.2 kg) volunteered to participate. CAI inclusion criteria were in accordance with the International Ankle Consortium guidelines. Relative to the controls, CAI participants had a history of multiple lateral ankle sprains (4.0 ± 2.1 vs. 0.0 ± 0.0 sprains), multiple giving way episodes within the past 6 months (6.6 ± 5.1 vs. 0.0 ± 0.0 episodes), higher Identification of Functional Ankle Instability scores (22.9 ± 2.8 vs. 0.1 ± 0.5), and greater limitations in self-reported function based on the Foot and Ankle Ability Measure (85.9 ± 9.7% vs. 100.0 ± 0.0%) and Foot and Ankle Ability Measure Sport (68.4 ± 20.6% vs. 100.0 ± 0.0%). Proteoglycan density was assessed using T1ρ MRI with greater T1ρ relaxation times interpreted as reduced proteoglycan density. A Siemens Magnetom TIM Trio 3T scanner and an 8-channel flex coil in conjunction with three-dimensional Fast Low Angle Shot (FLASH) with a spin lock power at 500 Hz, five different spin lock durations (40, 30, 20,10, 0 ms) was used to acquire the T1ρ MRI. Participants were non-weight bearing for 30 minutes prior to the scan to unload the cartilage. Voxel by voxel T1rho relaxation times were calculated from a five image sequence created with a MatLab program. Segmentation of the T1ρ talar cartilage was performed manually using ITK-SNAP software. Four regions of interest: anteromeidal, anterolateral, posteromedial, and posterolateral were identified during segmentation. Mean T1ρ relaxation times in each region of interest were compared between CAI patients and healthy controls using independent sample t-tests and an a priori alpha level of 0.05. Results: The CAI and controls groups were similar in terms of their age, height, and mass (P ≥ 0.433). Measures of injury history and self-reported function differed between the groups (P < 0.001) as expected. CAI patients had significantly higher T1ρ relaxation times in three of the four regions of interest including the anterolateral region (CAI: 66.57 ± 11.42 ms, Control: 57.73 ± 5.91 ms, P = 0.013), posteromedial region (CAI: 63.48 ± 12.43 ms, Control: 54.71 ± 10.84 ms, P = 0.049), and posterolateral region (CAI: 65.97 ± 11.75 ms, Control: 54.20 ± 10.03 ms, P = 0.006). No differences were noted in the anteromedial region (CAI: 67.61 ± 13.30 ms, Control: 60.91 ± 13.65 ms, P = 0.184). Conclusions: CAI patients showed higher T1ρ relaxation times compared to controls in three of the four regions of interest suggesting reduced proteoglycan density in the talar cartilage. This finding supports the existing arthroscopic literature that illustrates early degenerative changes in CAI patients. Further research is needed to determine the underlying mechanisms of these degenerative changes and to identify therapeutic interventions capable of slowing the progression of these degenerative changes following lateral ankle sprains and CAI.

Comparative Outcomes for Treatment of Articular Cartilage Lesions in the Ankle with Particulated Juvenile Cartilage Allograft

Category: Ankle Introduction/Purpose: Treatment of osteochondral defects of the talus with particulated juvenile cartilage allograft is a relatively new procedure. Although other treatment options exist for large osteochondral defects of the talus, the potential advantage of particulated juvenile allograft is the ability to perform the procedure arthroscopically or through a minimal approach. No previous studies have looked at the results of an arthroscopic approach and no previous studies have compared an arthroscopic technique to an open approach. The purpose of this study was to compare the outcomes of an arthroscopic transfer technique to the previously published open technique. Methods: A total of 34 patients underwent treatment of talar cartilage lesions with juvenile particulated cartilage allograft. Twenty of these were done arthroscopically and 14 were done with an open arthrotomy. There was no statistically significant difference between the groups with respect to age, lesion width, lesion depth, lesion length, or operative time. Scores for 6 different validated outcome measures were recorded for patients in each group pre-operatively and subsequently at 6 months, 1 year, 18 months, and 2 years. Results: Comparing outcome measurements at each data point to baseline, there were no statistically significant post-operative differences found between open and arthroscopic approaches with regards to VAS Pain Scale, AOFAS Ankle-Hindfoot Scale, Foot and Ankle Ability Measure - Sport Scale, or SF12 Physical Health Scale. Conclusion: Treatment of talar articular cartilage lesions with particulated juvenile cartilage allograft is associated with improved outcomes at 2 years with regards to several validated outcome measures regardless of technique utilized. At 2 years follow up, there were no statistically significant differences in outcomes utilizing an arthroscopic technique versus open technique with the numbers given. This data supports the use of particulated juvenile cartilage allograft utilizing either arthroscopic or open techniques.

Viability of Talus Osteochondral Defect Cartilage for Chondrocyte Harvesting

Large talar cartilage defects can be treated with either autologous chondrocyte implantation or matrix autologous chondrocyte implantation. Both techniques depend on successful harvesting of the chondrocytes. In the past, they have come from the ipsilateral knee, which has been associated with donor site morbidity. We hypothesized that damaged cartilage from the talus can be used as a reliable source for chondrocyte cell harvesting in preparation for possible matrix-induced autologous chondrocyte implantation (MACI). Chondrocytes were harvested from the injured talar cartilage during ankle arthroscopy and sent to a cell laboratory, measured for initial biopsy weight, cultured for 4 to 6 weeks, and then analyzed for viability. A total of 151 patients were analyzed. The average biopsy initial weight was 187.1 mg. The average number of cells was 3.13 × 10(5). The viability of the chondrocytes provided by the manufacturer averaged 92.3% (range, 33%-100%). Chondrocytes harvested from the damaged talar articular cartilage were functional and proliferated with an average viability of 92%. This technique may provide a useful source of chondrocytes if needed for a future cell-based regenerative procedure such as MACI while eliminating the need to harvest chondrocytes from the knee or other intact areas of cartilage on the talus. Level IV, case series.