Full-thickness Cartilage Loss Research Articles

CartiMorph: A framework for automated knee articular cartilage morphometrics

We introduce CartiMorph, a framework for automated knee articular cartilage morphometrics. It takes an image as input and generates quantitative metrics for cartilage subregions, including the percentage of full-thickness cartilage loss (FCL), mean thickness, surface area, and volume. CartiMorph leverages the power of deep learning models for hierarchical image feature representation. Deep learning models were trained and validated for tissue segmentation, template construction, and template-to-image registration. We established methods for surface-normal-based cartilage thickness mapping, FCL estimation, and rule-based cartilage parcellation. Our cartilage thickness map showed less error in thin and peripheral regions. We evaluated the effectiveness of the adopted segmentation model by comparing the quantitative metrics obtained from model segmentation and those from manual segmentation. The root-mean-squared deviation of the FCL measurements was less than 8%, and strong correlations were observed for the mean thickness (Pearson’s correlation coefficient ρ∈[0.82,0.97]), surface area (ρ∈[0.82,0.98]) and volume (ρ∈[0.89,0.98]) measurements. We compared our FCL measurements with those from a previous study and found that our measurements deviated less from the ground truths. We observed superior performance of the proposed rule-based cartilage parcellation method compared with the atlas-based approach. CartiMorph has the potential to promote imaging biomarkers discovery for knee osteoarthritis.

Outcomes after Bipolar Osteochondral Allograft Transplantation in the Ankle

Category: Ankle Arthritis; Ankle Introduction/Purpose: Surgical treatment options for symptomatic, full-thickness articular cartilage loss in the ankle are not consistently effective in restoring ankle function. Osteochondral allograft transplantation provides a standard-of-care alternative for patients, however, outcomes reported to date have been only fair, with a high incidence of reoperation and revision. However, recent cartilage storage and preservation techniques have significantly improved the percent viable chondrocytes at the time of implantation in OCAs. These high-chondrocyte-viability allografts should lead to improved survivability of OCAs and improved outcome measures. This study aimed to document the initial outcomes for patients undergoing bipolar OCA transplantation in the ankle after advances in tissue preservation, transplantation techniques, and patient management strategies. Methods: Patients with symptomatic tibiotalar arthritis were prospectively enrolled into a registry designed to follow outcomes after OCA surgeries in the ankle. All patients underwent complete OCA replacement of their tibial plafond and talar dome, with most undergoing fibular articular resurfacing. All OCA were size and side matched and preserved in Missouri Osteochondral Allograft Preservation System (MOPS). Patients followed a standardized, procedure-specific rehabilitation protocol after surgery, including remaining non-weight bearing for 8 weeks, weekly therapy visits, limited step count during recovery, and avoidance of high impact activities until 1 year after surgery. Patients followed-up with their physician at regular post-operative timepoints. Radiographs and patient reported outcome measures (VAS, AAOS Foot and Ankle, PROMIS PF, PROMIS Mobility) were obtained at each follow-up visit. Demographic and operative data were collected from the electronic medical record. All reported complications, reoperations, revisions, and failures were recorded in the EMR. Results: 14 patients were included for analyses with 12 undergoing primary OCA transplantation, and 2 undergoing revision OCA transplantation. Mean age and follow up was 36 and 44.1 months, respectively. All patients underwent tibia and talus OCA transplantation, with 10/14 including a fibula OCA transplantation. Initial success was 92.9% with one documented failure (tibial OCA collapse). Radiographic assessments indicated OCA integration and maintenance of joint space in 12 patients (85.7%). AAOS and VAS pain scores improved significantly from preoperative measures at each timepoint (p=.002, p=.03), while postoperative improvements in PROMIS Mobility and PROMIS Physical Function scores did not reach significance (p>0.15) (Table 1). Patients that were non-adherent to postoperative restriction and rehabilitation protocols, all 1-year postoperative PROs were significantly lower than for patients who were adherent. Conclusion: Ankle osteoarthritis in young patients continues to present a challenging dilemma. Previous attempts at large bipolar OCAs in the ankle have yielded fair, to poor, results. However, recent advances in bulk osteochondral allograft preservation has improved chondrocyte viability. Based on the results of our study, the use of high-chondrocyte-viability allografts for OCA transplantation is a viable option for the treatment of symptomatic bipolar osteochondral defects in the ankle joint. However, post operative rehab protocols are equally important in determining outcomes, and patient selection and education is key to ensuring successful outcomes. Longer term follow up is ongoing.

Comparison of Knee Articular Cartilage Defect Size Between Measurements Obtained on Preoperative MRI Versus During Arthrotomy.

Treatment decisions for cartilage defects are often based on lesion size. Magnetic resonance imaging (MRI) is widely used to diagnose cartilage defects noninvasively; however, their size estimated from MRI may differ from defect sizes measured during arthrotomy, especially after debridement to healthy cartilage if undergoing autologous chondrocyte implantation. The purpose of this study was to evaluate the reliability of 2 methods to assess knee cartilage defect size on preoperative MRI and determine their accuracy in predicting postdebridement defect sizes recorded during arthrotomy. It was hypothesized that defect size would be predicted more accurately by the total area of abnormal articular cartilage rather than the area of full-thickness cartilage loss as identified on MRI. Cohort study (diagnosis); Level of evidence, 3. This study included 64 patients (mean age, 41.8 ± 9.6 years) who underwent autologous cell therapy. Each patient received a 3-T MRI at 6.1 ± 3.0 weeks before cell implantation. Three raters, a radiologist, a surgeon, and a scientist, measured (1) the full-thickness cartilage defect area and (2) the total predicted abnormal cartilage area, identified by an abnormal signal on MRI. Interrater reliability was assessed using the intraclass correlation coefficient (ICC). Actual pre- and postdebridement defect sizes were obtained from intraoperative surgical notes. Postdebridement surgical measurements were considered the clinical reference standard and were compared with the radiologist's MRI measurements. Eighty-seven defects were assessed, located on the lateral (n = 8) and medial (n = 26) femoral condyle, trochlea (n = 17), and patella (n = 36). The interrater reliability of the cartilage defect measurements on MRI was good to excellent for the full-thickness cartilage defect area (ICC = 0.74) and the total predicted abnormal cartilage area (ICC = 0.78). The median full-thickness cartilage defect area on MRI underestimated the median postdebridement defect area by 78.3%, whereas the total predicted abnormal cartilage area measurement underestimated the postdebridement defect area by 14.3%. Measuring the full-thickness cartilage defect area on MRI underestimated the area to treat, whereas measuring the total abnormal area provided a better estimate of the actual defect size for treatment.

Paper 52: Pre- and Post-operative Patient Management by an Integrated Care Team Reduces Postoperative Failure Rates Following Osteochondral Allograft Transplantation in the Knee

Objectives: To assess the effects of an integrated care team including a health behavior psychologist on postoperative adherence and associated outcomes for patients undergoing osteochondral and/or meniscus allograft transplantation in the knee. Methods: With IRB approval and documented informed consent, patients were prospectively enrolled into a registry dedicated to following outcomes after OCA and meniscus allograft transplantation surgery between January of 2016 and April of 2021. Patients undergoing primary osteochondral and/or meniscus allograft transplantation to address symptomatic full-thickness cartilage loss and/or meniscus deficiency were included. Patient adherence rates and outcomes were compared based on two cohorts: patients that did not see a behavioral health psychologist preoperatively, and patients that met preoperatively identify potential barriers to adherence, set expectations for postoperative protocols, and identify a plan to moderate risk factors to non-adherence. Patients in both cohorts met preoperatively with the rest of the integrated care team specializing in joint preservation. Data were collected preoperatively, and at all follow-up visits at 3 months, 6 months, and yearly post-operatively. Visual analog scale (VAS) pain scores, International Knee Documentation Committee scores, PROMIS Global Health, and PROMIS Pain interference scores were collected. Treatment failure was defined as any reoperation to revise any of the osteochondral and/or meniscus allografts (revision) or for conversion to arthroplasty in the affected knee. Functional survival (success) was defined as patient- reported pain and function scores improved from pre-operative levels without need for revision or arthroplasty. Patients were categorized as nonadherent when documented evidence of a break from the physical therapy protocol was recounted to a member of the healthcare team by the patient or their physical therapy provider. Data were included for analyses when applicable registry data were available for at least one year following surgery. Chi-square or Fisher’s exact tests were used to analyze differences in proportions, while unpaired t-Tests, one-way analysis of variance tests, or rank sum tests were used to assess significant differences in variables with continuous data. Significance was set a priori at p < 0.05. Results: For patients in the study (n=213), 23.4% were documented to be nonadherent. Of those who were nonadherent, 4 (8.0%) were in the Health Psych cohort versus 46 (92.0%) who were not. Patients in the No Health Psych cohort were significantly more likely to be nonadherent to postoperative rehabilitation protocols (p = .023, OR = 3.4). Tobacco use (p<.001, OR = 7.9), higher preoperative PROMIS Pain Interference score (p<.001), lower preoperative PROMIS Mental Health score (p<.001), older age (p<.001) and higher BMI (p<.001) were also significantly associated with nonadherence. 81.6% of adherent patients had successful outcomes (mean final follow-up 46.7 months, range 12-75), while 40% of nonadherent patients required revision or total knee arthroplasty during the study period, such that nonadherent patients were 3x more likely (p = .004) to experience treatment failure. In this cohort of patients, male sex (p<.001, OR = 3.4) and bipolar OCA transplantation surgeries (p<.001, OR = 5.0) were also significantly associated with increased risk for treatment failure. Conclusions: Preoperative education and postoperative support for patients provided by an integrated care team including a health psychologist can significantly improve adherence and outcomes following osteochondral and meniscal allograft transplantation in the knee.

Clinical Outcomes of Unicompartmental Knee Arthroplasty in Patients with Full-versus Partial-Thickness Cartilage Loss: A Systematic Review and Meta-Analysis.

The objective of the study was to compare postoperative patient-reported outcomes and reoperation rates following unicompartmental knee arthroplasty (UKA) between patients with full-thickness cartilage loss (FTCL) and partial-thickness cartilage loss (PTCL). Multiple databases, including PubMed, Embase, Cochrane Library, and CNKI, were searched until October 2019 for studies comparing the Oxford Knee Score (OKS), American Knee Society (AKS) score, and reoperation rates between patients with FTCL and PTCL following UKA. Data analysis was performed using Review Manager software. A total of 613 UKA cases from 5 retrospective cohort studies were included. The mean difference in postoperative OKSs was significantly higher by 2.92 in FTCL group than in PTCL group (95% confidence interval [CI] = -5.29 to -0.55; P = 0.02). Improvement in OKS was significantly higher by 2.69 in FTCL group than in PTCL group (95% CI = -4.79 to -0.60; P = 0.01). However, the differences in OKSs were not clinically significant. The mean difference in AKS knee scores was similar between the 2 groups (95% CI = -9.14 to -3.34; P = 0.36), whereas the pooled mean difference in AKS function scores was higher by 5.63 in FTCL group than in PTCL group (95% CI = -9.27 to -1.98; P = 0.002), which was clinically relevant. The reoperation rates were statistically higher in PTCL group than in FTCL group (odds ratio = 2.24; 95% CI = 1.15 to 4.38; P = 0.02). Patients with FTCL achieved superior postoperative patient-reported outcomes and lower reoperation rates following UKA compared with those with PTCL. Thus, we believe this procedure should only be applied to end-stage medial osteoarthritis of the knee joint.

Evaluation of a modified subchondroplasty technique in an equine full-thickness cartilage defect model: a pilot study

To perform a pilot study with the intent of assessing the feasibility of a modified subchondroplasty (mSCP) technique in a validated preclinical equine model of full-thickness articular cartilage loss and evaluate the short-term patient response to the injected materials. 3 adult horses. Two 15-mm-diameter full-thickness cartilage defects were created on the medial trochlear ridge of each femur. Defects were treated with microfracture and then filled by 1 of 4 techniques: (1) autologous fibrin graft (FG) via subchondral injection of fibrin glue (FG), (2) autologous fibrin graft via direct injection of FG, (3) subchondral injection of a calcium phosphate bone substitute material (BSM) with direct injection of FG, and (4) untreated control. Horses were euthanized after 2 weeks. Patient response was evaluated via serial lameness examination, radiography, magnetic resonance imaging, computed tomography, gross evaluation, microcomputed tomography, and histopathology. All treatments were successfully administered. The injected material perfused through the underlying bone into the respective defects without adversely affecting the surrounding bone and articular cartilage. Increased new bone formation was seen at the margins of the trabecular spaces containing BSM. There was no treatment effect on the amount or composition of tissue within defects. The mSCP technique was a simple, well-tolerated technique in this equine articular cartilage defect model without significant adverse effects to host tissues after 2 weeks. Larger studies with long-term follow-ups are warranted.

Results of Treating Mild to Moderate Knee Osteoarthritis with Autologous Conditioned Adipose Tissue and Leukocyte-Poor Platelet-Rich Plasma.

Knee osteoarthritis (KOA) is one of the most common musculoskeletal disorders. Much progress has been made in regenerative medicine for the symptomatic treatment of KOA, including products containing stromal vascular fraction (SVF) and platelet-rich plasma (PRP). The aim of this study was to evaluate clinical and radiological findings after the application of autologous conditioned adipose tissue (ACA) and leukocyte-poor PRP (LP-PRP) in patients with mild to moderate KOA. A total of 16 patients (eight male and eight female) with changes related to KOA on the magnetic resonance imaging (MRI), but without severe osteophytosis, full-thickness cartilage loss, or subchondral bone involvement were included in this study. Patients received an intraarticular, ultrasound-guided injection of ACA and LP-PRP. Clinical scores, including a visual analog scale for pain (VAS), Knee Injury and Osteoarthritis Outcome Score (KOOS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were evaluated at baseline and at the three and six month follow-ups showing a statistically significant improvements at three and six months post-intervention. Furthermore, the delayed gadolinium-enhanced MRI of the cartilage (dGEMRIC) indices were evaluated at baseline and at the three and six month follow-ups showing no significant changes after treatment with ACA and LP-PRP, which were actually equal to the dGEMRIC indices measured in the control group (hyaluronic acid applied in contralateral knees without osteoarthritis). ACA with LP-PRP presents a viable minimally invasive therapeutic option for the clinical improvement of mild to moderate KOA. However, MFAT produced by different systems is likely to differ in cellular content, which can directly affect the paracrine effect (cytokine secretion) of mesenchymal stem cells and consequently the regeneration process.

Are the functional outcomes really inferior following unicondylar knee arthroplasty in patients with partial-thickness cartilage loss?

The main indication for medial Unicondylar Knee Arthroplasty (UKA) is Full-Thickness Cartilage Loss (FTCL) in the isolated medial compartment of the knee. However, controversial outcomes were reported in patients with Partial-Thickness Cartilage Loss (PTCL). The aim of this study is to compare PTCL and FTCL based on intraoperative findings in medial UKA in terms of functional outcomes and complication rates requiring reoperation and revision. Two hundred and fifteen knees of 174 patients who underwent mobile-bearing UKA between October 2014 and February 2018 for the diagnosis of symptomatic anteromedial osteoarthritis were evaluated retrospectively. A single senior surgeon evaluated the type of cartilage loss in the medial compartment intraoperatively according to the International Cartilage Repair Society classification system. Clinical outcomes were evaluated using Oxford Knee Score (OKS) and International Knee Documentation Committee (IKDC) score pre- and post-operatively at the last follow-up. Patients with PTCL and FTCL were compared in terms of their pre- and post-operative OKS and IKDC scores, and their improvements, as well as complication rates requiring reoperation and revision. The mean follow-up time was 33.1 ± 5.3 months. The PTCL (n = 80) and FTCL (n = 135) groups were statistically similar in terms of age (P = 0.41), gender (P = 0.921), body mass index (P = 0.165), bilaterality (P = 0.111), American Society of Anesthesiologists physical status (P = 0.218), Charlson Comorbidity Index (P = 0.74), and post-operative follow-up (P = 0.167). The mean pre-operative OKS and IKDC scores were improved from 24.5 ± 4.1 and 39.9 ± 5 to 40.3 ± 3.6 and 73.9 ± 7.7 at the last follow-up, respectively (P < 0.001). Pre-operative OKS and IKDC scores were superior in favor of the PTCL group. However, no significant difference was found between the groups in terms of post-operative OKS (P = 0.53) and IKDC (P = 0.975) scores, and their improvements (OKS, P = 0.953; IKDC, P = 0.536). The complication rates requiring reoperation was 5% (n = 11) in all patients. Of these, 9% (n = 7) from the PTCL group and 3% (n = 4) from the FTCL group were reoperated. Nevertheless, no significant difference was found between the groups (P = 0.105). In PTCL, medial UKA is a reliable surgery in terms of functional outcomes, the same as in FTCL; however, its complication rates requiring reoperation is higher without statistical significance. Level III, Therapeutic Study.

How Well Does MRI Predict Chondral Lesions in Patients with Femoroacetabular Impingement? An Analysis of 545 Cases (137)

Objectives:Articular cartilage injury has been identified as a risk factor for poor outcomes following hip arthroscopy for femoroacetabular impingement syndrome (FAI). The purpose of this study was to evaluate the efficacy of magnetic resonance imaging (MRI) in detecting cartilage defects, and to identify specific MRI findings associated with cartilage injury.Methods:All patients undergoing hip arthroscopy between February 2015 and May 2017 at one institution were enrolled in a prospective cohort. Intra-articular findings were documented at the time of surgery. MRI reports were retrospectively reviewed for radiologist-reported articular cartilage, osseous or synovial abnormalities. Sensitivity and specificity of MRI findings were calculated; multivariate logistic regression analysis determined which findings were associated with high-grade chondral damage at time of arthroscopy and used to create an online risk calculator, https://orthop.washington.edu/hiprisk/.Results:Out of a total of 598 patients who underwent hip arthroscopy, 550 had MRI reports available for review (92%). Grade III and IV cartilage injuries were reported on arthroscopy in 70 patients (13%) of average age 33 ± 13 years. On univariate analyses, individual MRI findings were not found to be sensitive in detection of articular cartilage injury (mean 22%, range 1.4% – 46%), but positive findings were highly specific (mean 90%, range 76% – 99%). Multivariate analysis revealed that older age (OR 1.09 [1.06-1.11], p < .001) and osseous findings such as subchondral cyst or edema (OR 4.77 [2.51-9.05], p <.001) were most predictive of grade III and IV defects (p < .001). An example of use of the online calculator is in Figure 1.Conclusions:MRI was a specific but not sensitive tool in diagnosing articular cartilage injury. Surgeons should be aware that osseous findings such as cysts or edema are highly predictive of full-thickness cartilage loss in FAI.

Relationship Between Magnetic Resonance Imaging Features and Knee Pain Over Six Years in Knees Without Radiographic Osteoarthritis at Baseline.

ObjectiveTo explore whether magnetic resonance imaging (MRI) features suggestive of knee osteoarthritis (OA) are associated with presence of knee pain in possible early‐stage OA development.MethodsWe included 294 participants from the Osteoarthritis Initiative (mean ± SD age 50 ± 3 years; 50% women) with baseline Kellgren/Lawrence grade of 0 in both knees, all of whom had received knee MRIs at 4 different time points over 6 years (baseline, 24, 48, and 72 months). Using a linear mixed model (knees matched within individuals), we studied whether MRI features (meniscal body extrusion [in mm], cartilage area loss [score 0–39], cartilage full thickness loss [range 0–16], osteophytes [range 0–29], meniscal integrity [range 0–10], bone marrow lesions [BMLs] including bone marrow cysts [range 0–20], Hoffa‐ or effusion‐synovitis [absent/present], and popliteal cysts [absent/present]) were associated with knee‐specific pain as reported on the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire using a 0–100 scale (worst to best).ResultsThe differences in KOOS knee pain score for a knee with a 1 unit higher score on MRI were the following: meniscal extrusion –1.52 (95% confidence interval [95% CI] –2.35, –0.69); cartilage area loss –0.23 (95% CI –0.48, 0.02); cartilage full thickness loss –1.04 (95% CI –1.58, –0.50); osteophytes –0.32 (95% CI –0.61, –0.03); meniscal integrity –0.28 (95% CI –0.58, 0.02); BMLs including potential cysts –0.19 (95% CI –0.55, 0.16); synovitis 0.23 (95% CI –1.14, 1.60); and popliteal cysts 0.86 (95% CI –0.56, 2.29).ConclusionMeniscal extrusion, full thickness cartilage loss, and osteophytes are associated with having more knee pain. Although these features may be relevant targets for future trials, the clinical relevance of our findings is unclear because no feature was associated with a clinically important difference in knee pain.

Humeral Head Morphology Influences Outcomes of Arthroscopic Interposition Glenoid Patch Allograft for Glenohumeral Arthritis

PurposeTo determine short- to midterm patient-reported outcomes of arthroscopic soft-tissue interposition arthroplasty using acellular dermal allograft with a minimum follow-up of 1 year and to assess outcomes in patients with and without flattening of the humeral head.MethodsPatients with a diagnosis of primary glenohumeral arthritis who underwent arthroscopic soft-tissue interposition arthroplasty with an acellular dermal allograft from July 2010 to November 2019 were retrospectively enrolled. Inclusion criteria were a primary diagnosis of glenohumeral arthritis and Outerbridge 4 full-thickness cartilage loss of ≥50% of the glenoid articular surface. Patients underwent arthroscopic debridement, microfracture, and biological arthroscopic soft-tissue interposition arthroplasty with an acellular dermal matrix. Postoperative outcomes included American Shoulder and Elbow Surgeon (ASES) score, Single Assessment Numeric Evaluation (SANE) score, Penn Shoulder Score (PSS), numeric rating scale (NRS) pain score, analgesic use, and conversion to total shoulder arthroplasty (TSA). Results were stratified according to humeral head morphology on preoperative radiographs.ResultsA total of 25 patients were included, with a mean age of 56.0 years (range 19.2 to 74.8) and a mean follow-up of 3.36 years (range 1.03 to 8.98). The mean postoperative ASES score was 64.1 (range 11.7 to 100.0), SANE score was 62% (range 5% to 100%), and PSS was 61.2 (range 10.6 to 97.9). Additionally, 56% of patients rated their shoulder function as improved or much improved, and 36% of patients converted to TSA at a mean of 2.35 years. Patients with and without humeral flattening had similar postoperative ASES scores (P = .44), SANE scores (P = .90), PSS (P = .73), and conversions to TSA (P = .83). Patients with humeral flattening were more likely to have shoulder pain at night (83.3% versus 28.6%, P = .02).ConclusionArthroscopic soft-tissue interposition arthroplasty with an acellular dermal allograft resulted in satisfactory short- to mid-term postoperative outcomes for younger patients with glenohumeral arthritis but demonstrated a TSA conversion rate of 36%. Patients with humeral head flattening also had satisfactory shoulder function but were more likely to experience shoulder pain at night.Level of EvidenceLevel IV, therapeutic case series

Clinical value of weight-bearing CT and radiographs for detecting patellofemoral cartilage visualized by MRI in the MOST study

The patellofemoral joint is frequently affected by osteoarthritis (PFOA) and is incompletely imaged on radiographs (XR). Weight-Bearing CT (WBCT) could offer advantages for visualization. This study determined the sensitivity, specificity, and accuracy of axial WBCT and lateral XR for detection of PFOA features in comparison with cartilage damage on MRI. A convenience sample of 60 right knees from the MOST cohort were analyzed. WBCT and XR were read for OARSI JSN score and MRI for MOAKS cartilage score by two experienced musculoskeletal radiologists blinded to participant. Using MOAKS scoring on MRI (referent standard), the sensitivity, specificity and accuracy of patellofemoral OARSI JSN scores based on WBCT and XR were compared. The mean±SD age and BMI for the participants included (66.7% women) were 67.6±9.8 years and 30.0±5.3kg/m2 respectively. WBCT demonstrated significantly greater sensitivity (0.85-0.97 on WBCT vs 0.47-0.57 on XR) and accuracy (0.85-0.92 on WBCT vs 0.48-0.57 on XR) for all parameters except lateral full-thickness cartilage loss (McNemar's test p-values all <0.001). There was moderate-to-strong and low-to-moderate agreement between PFOA findings on WBCT and XR, respectively, and semi-quantitative scores of PF cartilage on MRI. Inter-rater reliability for XR JSN [weighted kappa=0.83 (0.64, 1.0)], WBCT JSN [kappa=0.60 (0.48, 0.72)] and MRI MOAKS-CM [kappa=0.70 (0.61, 0.79)] readings were good. WBCT demonstrates significantly greater sensitivity and accuracy than radiographs for identification of PFOA. Given the same Relative Radiation Level as XR and improved visualization, WBCT holds promise to improve understanding of the weight-bearing patellofemoral joint.

Intra-Articular Atelocollagen Injection for the Treatment of Articular Cartilage Defects in Rabbit Model

Atelocollagen is widely recognized as a biomaterial for regenerative medicine because of its good compatibility and low antigenicity. Injury of the outermost layer of articular cartilage, known as the lamina splendens, can lead to osteoarthritis (OA) and eventually full-thickness cartilage loss. The intra-articular injection of atelocollagen has been designed to restore the cartilage layer and cartilage defects in OA joints. In this study, we investigated the efficacy of atelocollagen as a cartilage supplement for joint defects. In this study, we evaluated the therapeutic effects of atelocollagen in animals with cartilage defects. Femoral groove defects were artificially created in 12 male New Zealand white rabbits, which were treated with intra-articular injection of either atelocollagen (experimental) or normal saline (control). The results were observed 3, 6, 9, and 12weeks following macroscopic and histological evaluations. At 3weeks, cartilage tissue was restored in the experimental group, whereas the control group did not show signs of restoration. At 12weeks, defects in both groups were filled with regenerated tissue, but the experimental group displayed a morphologically better appearance. Histologically, the regenerated tissue in the experimental group showed statistically significant improvement compared to the control group, with a structure similar to that of normal articular cartilage. The results showed that the intra-articular injection of atelocollagen enhanced cartilage regeneration following rabbit patellar groove defects. Therefore, intra-articular injection of atelocollagen can be used as an effective supplement for joint defects.

Radiographic severity, extent and pattern of cartilage loss are not associated with patient reported outcomes before or after total knee arthroplasty in end-stage knee osteoarthritis

BackgroundThe aim of this study was to determine if radiographic severity, extent or pattern of knee osteoarthritis was associated with pain and function before total knee arthroplasty (TKA) or improvement therein one year after TKA. MethodsA prospective study of 259 patients undergoing unilateral TKA for Kellgren-Lawrence (KL) grade ≥ 3 knee osteoarthritis was conducted: mean age 69.8 ± 9.7 (44–91); mean BMI 31.0 ± 5.8 (17–52); 152/259 (58.7%) female. Preoperative radiographs were assessed using the KL and Ahlback systems. Preoperatively and 1 year postoperatively patients completed Oxford Knee Scores, VAS-Pain and EQ-5D scores. Full thickness cartilage loss was recorded intraoperatively. ResultsMedian radiographic severity was Ahlback 2, KL 4: 51/259 (19.7%) hypertrophic; 23/259 (8.8%) atrophic. Neither Ahlback nor Kellgren-Lawrence OA grade was associated with OKS, VAS Pain or EQ-5D prior to TKA (p > 0.05). The extent and pattern of cartilage loss did not affect preoperative PROMs. Radiographic OA severity, compartment involvement, and pattern of cartilage loss were not significantly associated with PROMs or improvements therein following TKA (p > 0.05). Hypertrophic OA was associated with less pain before TKA (difference 6.8, 0.23–13.9 95%CI, p = 0.044), and worse improvement in OKS following TKA (difference −3.41, −6.8 to −0.05 95%CI, p = 0.047). Better preoperative OKS and hypertrophic OA were independently associated with poorer improvement in OKS 1 year following TKA (R2 = 0.208). ConclusionProvided at least one compartment has KL grade ≥ 3 changes, further radiographic severity, pattern or extent of cartilage loss did not affect PROMs before or after TKA: multicompartmental was no worse than unicompartmental disease.

Outcomes of rotator cuff repair with concurrent microfracture of focal glenohumeral osteoarthritis

The benefit of rotator cuff repair (RCR) in patients with concurrent osteoarthritic changes remains unclear. RCR has the theoretical potential to increase the compressive force across the glenohumeral joint, further exacerbating osteoarthritis pain. The purpose of this study is to investigate pain relief and patient-reported outcomes of patients undergoing simultaneous RCR and microfracture of focal glenohumeral osteoarthritis. Thirty-four patients undergoing simultaneous RCR and microfracture were retrospectively reviewed at a minimum 1-year follow-up. Patient demographics, preoperative range of motion, functional outcomes (visual analog scale [VAS], Single Assessment Numeric Evaluation [SANE], American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form [ASES], and Simple Shoulder Test [SST]), and operative metrics were recorded. The patients were then contacted to obtain postoperative functional outcome scores (VAS, SANE, ASES, and SST). Twenty-seven patients (11 male/16 female [79%]) were evaluated at a mean follow-up of 25.8 months (range, 12-46). The average age at surgery was 64.9 years (range, 56-78). Chronic tears were more common than acute tears (57.7% vs. 42.3%). The majority of patients had a full rotator cuff tear (89%) involving a mean 1.7 ± 0.8 tendons (range, 1-3). Eighty-eight percent of the humeral lesions were Outerbridge 4 compared with 84% on the glenoid. The mean estimated involvement between the 2 groups with 38.4% ± 18.4% of the humeral head involved and 34.6% ± 18.4% of the glenoid involved. PRO scores improved postoperatively with a reduction in mean VAS (6.6-2.0, P < .01), SANE (33.8-79.8, P < .01), ASES (38.0-80.9, P < .01), and SST (3.07-9.70, P < .01) scores. Cumulatively, only 52% (14/27) of the patients improved, however, by the MCID for all collected PROs. Our results demonstrate modest improvements in postoperative pain and functional scores at a minimum of 1-year follow-up in a cohort of patients who have undergone RCR and glenohumeral microfracture. In cases of small focal lesions of full-thickness cartilage loss, RCR with microfracture is a reasonable treatment option; however, patients should be counseled on expectations accordingly.

Immunosuppressive regulatory T cells are unable to suppress T helper 17 cells in post-traumatic osteoarthritis

Immunosuppressive regulatory T cells are unable to suppress T helper 17 cells in post-traumatic osteoarthritis

Magnetic Resonance Imaging Predictors of Chondral Lesions in Patients With Femoroacetabular Impingement: An Analysis of 545 Cases

A large prospective cohort was used (1) to evaluate the overall ability of magnetic resonance imaging (MRI) to detect Outerbridge grade III and IV cartilage defects found during surgery and (2) to identify the specific MRI findings most associated with these cartilage defects so that the practicing hip arthroscopist can better predict cartilage injury before surgery. All patients undergoing hip arthroscopy between February 2015 and May 2017 at 1 institution were enrolled in a prospective cohort. Intra-articular findings were documented at the time of surgery. MRI reports were retrospectively reviewed for radiologist-reported articular cartilage, osseous, or synovial abnormalities. Sensitivity and specificity of MRI findings were calculated; multivariate logistic regression analysis determined which findings were associated with high-grade chondral damage at the time of arthroscopy and used to create an online risk calculator, https://orthop.washington.edu/hiprisk/. Of 598 patients who underwent hip arthroscopy, 550 had MRI reports available for review (92%). Grade III and IV cartilage injuries were reported on arthroscopy in 70 patients (13%) of average age 33 ± 13 years. On univariate analyses, individual MRI findings were not sensitive in detection of articular cartilage injury (mean 22%; range, 1.4%-46%), but positive findings were highly specific (mean 90%,; range, 76%-99%). Multivariate analysis revealed that older age (odds ratio [OR] 1.09 [1.06-1.11], P < .001) and osseous findings such as subchondral cyst or edema (OR 4.77 [2.51-9.05], P < .001) were most predictive of grade III and IV defects (P < .001). MRI was a specific but not sensitive tool in diagnosing articular cartilage injury. Surgeons should be aware that osseous findings such as cysts or edema are highly predictive of full-thickness cartilage loss in FAI. Level III, development of diagnostic criteria (consecutive patients with consistently applied reference standard, no blinding).

Efficacy and mid/long-term survivorship of mobile-bearing unicompartmental knee arthroplasty for medial compartment knee osteoarthritis combined patellofemoral joint arthritis: a prospective cohort study protocol

IntroductionUnicompartmental knee arthroplasty (UKA) is one of the most effective surgical procedures for treating isolated medial compartment knee osteoarthritis. However, previous studies have regarded patellofemoral osteoarthritis as a contraindication for...

Patterns of cartilage loss and anterior cruciate ligament status in end-stage osteoarthritis of the knee.

This study aims to determine the proportion of patients with end-stage knee osteoarthritis (OA) possibly suitable for partial (PKA) or combined partial knee arthroplasty (CPKA) according to patterns of full-thickness cartilage loss and anterior cruciate ligament (ACL) status. A cross-sectional analysis of 300 consecutive patients (mean age 69 years (SD 9.5, 44 to 91), mean body mass index (BMI) 30.6 (SD 5.5, 20 to 53), 178 female (59.3%)) undergoing total knee arthroplasty (TKA) for Kellgren-Lawrence grade ≥ 3 knee OA was conducted. The point of maximal tibial bone loss on preoperative lateral radiographs was determined as a percentage of the tibial diameter. At surgery, Lachman's test and ACL status were recorded. The presence of full-thickness cartilage loss within 16 articular surface regions (two patella, eight femoral, six tibial) was recorded. According to articular cartilage loss and ACL status, 195/293 (67%) were suitable for PKA or CPKA: medial unicompartmental knee arthroplasty (UKA) 97/293 (33%); lateral UKA 25 (9%); medial bicompartmental arthroplasty 31 (11%); lateral bicompartmental arthroplasty 12 (4%); bicondylar-UKA 23 (8%); and patellofemoral arthroplasty (PFA) seven (2%). The ACL was intact in 166 (55%), frayed in 82 (27%), disrupted in 12 (4%), and absent in 33 (11%). Lachman testing was specific (97%) but poorly sensitive (38%) for disrupted/absent ACLs. The point of maximal tibial bone loss showed good interclass correlation (ICC 0.797, 0.73 to 0.85 95% confidence interval (CI); p < 0.001) and was more posterior when the ACL was absent. Maximum tibial bone loss occurring at > 55% of the anterior to posterior distance predicted ACL absence with 93% sensitivity and 91% specificity (area under the curve 0.97 (0.94 to 0.99 95% CI; p < 0.001). ACL status can be reliably determined from a lateral radiograph using the location of maximal tibial bone loss. According to regions of cartilage loss and ACL status, two-thirds of patients with end-stage knee OA could potentially be treated with PKA or CPKA. Cite this article: Bone Joint J 2020;102-B(6):716-726.

Association of baseline and change in tibial and femoral cartilage thickness and development of widespread full-thickness cartilage loss in knee osteoarthritis – data from the Osteoarthritis Initiative

To investigate whether baseline cartilage thickness and its longitudinal change are associated with incident widespread full-thickness cartilage loss (wsFTCL) in knee osteoarthritis, and whether there are optimal cut-off values for predicting wsFTCL. Central medial tibial (cMT) and femoral (cMF) cartilage were assessed using quantitative magnetic resonance imaging data from the Osteoarthritis Initiative cohort (N=600 knees). Cartilage thickness was measured at baseline and 12 months. wsFTCL was defined semi-quantitatively (scores 2 and 3 from the MRI Osteoarthritis Knee Score) and its incidence at 24 months recorded. Logistic regression was used to determine the odds of developing wsFTCL for baseline and for each 0.1mm decrease in cartilage thickness. Cut-off values were investigated using the minimal-p method and area under the Receiver Operating Characteristic curves (AUC). Incident wsFTCL was observed in 66 (12%) and 73 (14%) knees in cMT and cMF, respectively. Lower baseline cMT and cMF cartilage thickness values were associated with wsFTCL (OR=1.20; 95% CI: 1.11, 1.28 and OR=1.15; 95% CI: 1.06 to 1.24, respectively). Optimal cut-off AUCs for the tibia and femur were 0.64 (0.57-0.70) and 0.63 (0.57-0.69), respectively. Longitudinal decrease in femoral, but not tibial, cartilage thickness was associated with incident wsFTCL (OR=1.77; 95% CI: 1.30 to 2.40); optimal cut-off AUC 0.65 (95% CI: 0.58-0.72). Lower baseline cMT and baseline/change (decrease) over 12 months in cMF cartilage thickness were associated with incident, location-specific, wsFTCL at 24 months. Optimal cut-off values were relatively low and of uncertain utility for predicting incident wsFTCL.