Cartilage Lesions Research Articles

Evaluation of the impact of ultra-trail running on knee cartilage using magnetic resonance imaging t2 mapping.

Ultra-marathon trails involve a combination of specific physiological and mechanical constraints and raise new questions regarding the osteoarticular impact on the knees and the long-term risk of osteoarthritis. Magnetic resonance imaging (MRI) T2 relaxation time measurement has shown the ability to determine cartilage response to loading. Higher T2 measurements correspond with cartilage damage. The aim of this study was to quantify the changes in MRI T2 relaxation times of knee articular cartilage after an ultra-trail run and determine knee's consequences of regular practice. Twenty participants in a 55-km race involving total elevation changes of 2600m had 1.5-T knee MRI prior to the race (V0), immediately after (V1) and one month after the race (V2) for T2 relaxation times measurement and morphological sequences (T1, T2 & T2 Fast-Spin Echo (FSE)). T2 measurements were significantly increased in V1 from V0 and remained so one month after the race (V2), despite a significant reduction from V1. Morphological sequences revealed that 65% of the participant had cartilage damage and 65% meniscal damage, 100% of which affected the posterior horn of the medial meniscus. Only one subject (5%) presented no anomaly whatsoever. Damage appeared to be stable between the assessments. Ultra-trail running leads to modifications in the knee cartilage ultrastructure, which persists for at least one month after the event. Furthermore, regular ultra-trail runners present a high number of low-grade cartilage and meniscus lesions.

Magnetic Resonance Imaging Features and Functional Score in Patients Requiring Total Knee Arthroplasty.

Introduction Knee osteoarthritis (KOA) is a progressive degenerative disease, with an increasing prevalence among the population. The degenerative changes in KOA affect the cartilage, menisci, synovial tissue, and subchondral bone. The treatment for patients in advanced stages of the disease is total knee arthroplasty (TKA). The purpose of this descriptive study is to identify the MRI features in the case of patients with KOA who did not obtain an improvement in symptoms and joint function after the non-surgical treatmentsand who applied for surgical treatment, i.e. TKA. Also, we aimed to identify the correlations between the MRI changes and the functional score of the patients, as well as the inter-variable correlations. Materials and methods The study was conducted in the Department of Orthopedics and Traumatology at the University Emergency Hospital of Bucharest between January 1, 2023, and January 31, 2024. It included 50 patients who required TKA. This study is a prospective, observational, and descriptive analysis focusing on patients scheduled for TKA. Results The patients in the study group who required TKA had a Knee Society Score (KSS) ranging from 35 to 70and a KSS function score between 24 and 60. Among them, 98% had tricompartmental lesions of the articular cartilage, and 100% presented with osteophytes, even when they were not identifiable radiologically. Additionally, 58% of the patients had changes in the infrapatellar fat pad, 66% presented with joint effusion without any traumatic history, and 86% of the patients had partial or complete lesions of the anterior cruciate ligament. Conclusion TheMRI pattern of the patient who requires TKA consists of the presence of articular cartilage lesions in more than two compartments with exposure of the subchondral bone and diameter greater than 1 cm, meniscus lesions (>grade 2), meniscus extrusion (>grade 1), the presence of bone marrow lesions (BMLs) in the medial or lateral compartment of the femur or tibia, hyperintense signal of the infrapatellar fat pad, anterior cruciate ligament (ACL) lesions (>grade 2), and the presence of osteophytes together with the presence of effusion in the suprapatellar bursa. BMLs and changes in the infrapatellar fat pad may lead to the opening of new research perspectives explaining the complex changes in KOA in relation to the inflammatory process and gene expression.

Arthroscopic device with bendable tip for the controlled extrusion of hydrogels on cartilage defects

Advanced tools for the in situ treatment of articular cartilage lesions are attracting a growing interest in both surgery and bioengineering communities. The interest is particularly high concerning the delivery of cell-laden hydrogels. The tools currently available in the state-of-the-art hardly find an effective compromise between treatment accuracy and invasiveness. This paper presents a novel arthroscopic device provided with a bendable tip for the controlled extrusion of cell-laden hydrogels. The device consists of a handheld extruder and a supply unit that allows the extrusion of hydrogels. The extruder is equipped with a disposable, bendable nitinol tip (diameter: 4 mm, length: 92 mm, maximum bending angle: 90°) that guarantees access to hard-to-reach areas of the joint, which are difficult to get to, with conventional arthroscopic instruments. The tip accommodates a biocompatible polymer tube that is directly connected to the cartridge containing the hydrogel, whose plunger is actuated by a volumetric or pneumatic supply unit (both tested, in this study). Three different chondrocyte-laden hydrogels (RGD-modified Vitrogel®, methacrylated gellan gum, and an alginate–gelatine blend) were considered. First, the performance of the device in terms of resolution in hydrogel delivery was assessed, finding values in the range between 4 and 102 µL, with better performance found for the pneumatic supply unit and no significant differences between straight tip and bent tip conditions. Finite element simulations suggested that the shear stresses and pressure levels generated during the extrusion process were compatible with a safe deposition of the hydrogels. Biological analyses confirmed a high chondrocyte viability over a 7-day period after the extrusion of the three cell-laden hydrogel types, with no differences between the two supply units. The arthroscopic device was finally tested ex vivo by nine orthopedic surgeons on human cadaver knees. The device allowed surgeons to easily deliver hydrogels even in hard-to-reach cartilage areas. The outcomes of a questionnaire completed by the surgeons demonstrated a high usability of the device, with an overall preference for the pneumatic supply unit. Our findings provide evidence supporting the future arthroscopic device translation in pre-clinical and clinical scenarios, dealing with osteoarticular treatments.

Comparative Study of Autogenic and Allogenic Chondrocyte Transplants on Polyethersulfone Scaffolds for Cartilage Regeneration.

The aim of this study was to evaluate the chondrogenic potential of chondrocyte transplants cultured in vitro on polyethersulfone (PES) membranes. Forty-eight rabbits (96 knee joints) were used in the project. The synthetic, macro-porous PES membranes were used as scaffolds. Fragments of articular cartilage were harvested from non-weight-bearing areas of the joints of the animals. Chondrocytes were isolated and then cultivated on PES scaffolds for 3 weeks. The animals were divided into four groups. All the lesions in the articular cartilage were full thickness defects. In Group I, autogenic chondrocytes on PES membranes were transplanted into the defect area; in Group II, allogenic chondrocytes on PES membranes were transplanted into the defect area; in Group III, pure PES membranes were transplanted into the defect area; and in Group IV, lesions were left untreated. Half of the animals from each group were terminated after 8 weeks, and the remaining half were terminated 12 weeks postoperatively. The samples underwent macroscopic evaluation using the Brittberg scale and microscopic evaluation using the O'Driscoll scale. The best regeneration was observed in Groups II and I. In Group I, the results were achieved with two surgeries, while in Group II, only one operation was needed. This indicates that allogenic chondrocytes do not require two surgeries, highlighting the importance of further in vivo studies to better understand this advantage. The success of the study and the desired properties of PES scaffolds are attributed mainly to the presence of sulfonic groups in the structure of the material. These groups, similar to chondroitin sulfate, which naturally occurs in hyaline cartilage, likely enable mutual affinity between the scaffold and cells and promote scaffold colonization by the cells.

Management of patellar and trochlear cartilage lesions with matrix-induced autologous chondrocyte implantation in conjunction with patellofemoral realignment procedures improves patient-reported outcomes and magnetic resonance image appearance

ObjectivesThe aim of this study is to evaluate the relationship between the achievement of clinically significant improvement in patient-reported outcome measures (PROMs) and the postoperative magnetic resonance image (MRI) appearance of matrix-associated chondrocyte implantation (MACI), in conjunction with patellofemoral realignment procedures, for the treatment of grade-IV chondral defects about the patellofemoral joint. MethodsA retrospective review of patients undergoing MACI for grade-IV chondral defects of the patella or trochlea by a single sports-medicine-fellowship-trained surgeon from 2017 to 2020 was performed. Concomitant realignment procedures, including tibial tubercle osteotomy and medial patellofemoral ligament reconstruction, were also performed as needed. Patients with preoperative and minimum 1-year postoperative PROMs and postoperative knee MRI were included. MRI scans were obtained at 6.3 (interquartile range: 5.8, 7.5) months postoperatively. A fellowship-trained musculoskeletal radiologist assigned a Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score (range: 0–100, with 100 equating to complete graft healing) to each MRI. Achievement of the minimal clinically important difference (MCID) for International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Score—Quality of Life, and Kujala scores were determined for each patient. Paired t-tests or Wilcoxon rank-sum tests were used to evaluate for an association between achievement of the MCID for each PROM and MOCART score. The average follow-up time and time from surgery to PROMs were 2.7 ​± ​1.5 years and 1.7 ​± ​0.66 years, respectively. ResultsThirty patients were included. There was a significant improvement in all PROMs from preoperative to postoperative (p ​< ​0.001). More than two-thirds of patients achieved the MCID for each PROM. Patients who achieved the MCID for IKDC had significantly higher MOCART scores (66.5 ​± ​16.2) than those who did not meet the MCID for IKDC (50.6 ​± ​23.6, p ​= ​0.043). ConclusionMACI for the treatment of patellofemoral chondral injuries is associated with clinically significant improvement in PROMs at short-term follow-up. Clinically significant improvements in IKDC scores are associated with a more mature MRI appearance of the autologous chondrocyte implantation graft on postoperative MRI, as indicated by higher MOCART scores. Level of evidenceIV—Case Series.

Higher Accuracy of Arthroscopy Compared to MRI in the Diagnosis of Chondral Lesions in Acute Ankle Fractures: A Prospective Study.

Even after successful surgery for acute ankle fractures, many patients continue having complaints. A possible explanation is the presence of concomitant chondral lesions. The aim of this study is to investigate the accuracy of MRI compared to that of arthroscopy in the assessment of chondral lesions in acute ankle fractures. In this prospective single-center study, patients presenting with acute ankle fractures over a period of three years were identified. A preoperative MRI was performed within a maximum of 10 days after trauma. During surgery, ankle arthroscopy was also performed. The International Cartilage Repair Society (ICRS) cartilage lesion classification was used to grade the detected chondral lesions. To localize the chondral lesions, the talar dome was divided into eight zones and the tibial/fibular articular surfaces into three zones. In total, 65 patients (28 females) with a mean age of 41.1 ± 15 years were included. In the MRI scans, 70 chondral lesions were detected (69.2% of patients) affecting mostly the tibial plafond (30%) and mostly graded as ICRS 3. The mean lesion area measured was 20.8 mm2. In the arthroscopy, 85 chondral lesions were detected (70.8% of patients) affecting mostly the medial surface of the talar dome (25.9%) and mostly graded ICRS 3. The mean lesion area measured was 43.4 mm2. The highest agreement between the two methods was observed in the size estimation of the chondral lesions. The present study shows the reduced accuracy of MRI when compared to arthroscopy in the assessment of traumatic chondral lesions in the setting of acute ankle fractures especially regarding lesion size. MRI remains an essential instrument in the evaluation of such lesions; however, surgeons should take this discrepancy into consideration, particularly the underestimation of chondral lesions' size in the preoperative planning of surgical treatment and operative technique.

Anatomical medial patellofemoral ligament reconstruction improves sport participation and activity levels in adolescents with recurrent patellar dislocation.

This study aims to evaluate the clinical outcomes of an anatomical medial patellofemoral ligament (MPFL) reconstruction and the effects of concomitant patellofemoral joint injuries and radiological findings on outcomes in adolescents with recurrent patellar dislocation (RPD). Between January 2011 and January 2020, a total of 34 patients (19 males, 15 females; median age: 15.6 years; range, 13 to 17 years) with RPD who underwent anatomic MPFL reconstruction were retrospectively analyzed. Lateral release was performed as indicated. Clinical outcomes were evaluated preoperatively and at the final follow-up using the Visual Analog Scale (VAS), Lysholm, Kujala, and Tegner activity rating scales. Magnetic resonance imaging was performed to detect concomitant injuries such as bone, cartilage, and soft tissue injuries. The mean follow-up was 5±2 years. All postoperative knee functions and activity levels were statistically significantly improved without re-dislocation (p<0.001). There was no statistically significant relationship between the presence and location of cartilage lesions and clinical outcomes (p>0.05). Patients with cartilage lesions had a significantly higher CatonDeschamps index and a higher incidence of bone edema in both the patella and femur than patients without. Anatomic MPFL reconstruction with meticulous physical therapy has successful clinical outcomes, prevents re-dislocation, and increases participation in sports and activity levels in adolescent patients with RPD. Although cartilage injuries are common after RPD, it has no adverse effect on clinical outcomes in the mid-term.

The Number of Patellar Dislocation Events Is Associated With Increased Chondral Damage of the Trochlea

Background: Patellofemoral instability is associated with chondral injuries to the patella, trochlea, and lateral femoral condyle. Although studies have demonstrated an association between patellar dislocations and chondral injuries, the influence of the number of dislocations on chondrosis is not established. Purpose: To elucidate the precise association between the number of patellar dislocation events and the severity of chondral injuries in a multicenter cohort study at the time of patellar stabilization procedures. Study Design: Cross-sectional study; Level of evidence, 2. Methods: A prospective multicenter cohort study (JUPITER [Justifying Patellar Instability Treatment by Early Results]) database was queried for cases of primary patellofemoral instability procedures from December 2016 to September 2022. Cartilage lesions were classified using the International Cartilage Repair Society (ICRS) classification system during an arthroscopic or open evaluation (direct visualization), with grades 2 to 4 considered abnormal. The number of dislocations was categorized as 1, 2-5, and >5. Categorical variables were compared with the chi-square test, and binary logistic regression was performed to identify predictors of the presence of chondral lesions. Results: A total of 938 knees (mean age, 16.2 ± 3.8 years; 61.4% female) were included, with 580 (61.8%) demonstrating a chondral injury. The most affected region was the patella (n = 498 [53.1%]), followed by the lateral femoral condyle (n = 117 [12.5%]) and trochlea (n = 109 [11.6%]). There were no differences in the presence (P = .17) or grade (P = .63) of patellar lesions by the number of dislocations. Patients with >5 dislocations more frequently had trochlear chondral lesions (19.8%) compared with those with fewer dislocations (1, 7.6%; 2-5, 11.0%; P < .001). More dislocations were also associated with a higher proportion of ICRS grade 2 to 4 trochlear lesions (>5, 15.3%; 2-5, 10.0%; 1, 6.9%; P = .015). Combined patellar and trochlear lesions were also more common in those with >5 dislocations (P = .001). In multivariable regression, >5 dislocations was the only variable predictive of a trochlear lesion (odds ratio, 3.03 [95% CI, 1.65-5.58]; P < .001). Conclusion: This large prospective cohort study demonstrated that recurrent patellar dislocations can lead to more severe chondral damage in specific locations in the knee. More than 5 dislocations was associated with a >3-fold increase in the incidence and severity of trochlear chondral injuries. There were no differences in the presence or grade of patellar lesions by the number of dislocations. These findings should caution surgeons regarding prolonged nonoperative treatment.

Anteromedial knee osteoarthritis (AMOA) evaluated with magnetic resonance imaging (MRI): a cohort study of 100 patients.

Magnetic resonance imaging (MRI) scans are increasingly used for knee osteoarthritis evaluation and preoperative planning before unicompartmental knee arthroplasty (UKA), and often patients already have MRI scans before their initial surgeon consultation. This highlights the need for surgeons to understand anteromedial osteoarthritis (AMOA) patterns on MRI. Hence, we aim to describe MRI findings in patients with AMOA meeting current indications for medial UKA. We analysed MRI scans from 100 knees evaluated for UKA between 2006 and 2013. Inclusion criteria comprised full-thickness medial compartment loss and intact lateral compartment joint space on preoperative radiographs. Assessment included cartilage lesions, osteophytes, meniscal damage, and anterior-cruciate ligament (ACL) status on tibial and femoral surfaces. Final decision to proceed with UKA relied on intraoperative findings, independent of MRI. Complete anteromedial tibial and femoral cartilage loss preserved posterior cartilage rims was evident in all cases. Cartilage thinning occurred in the lateral compartment in 34% of cases. While 62% displayed lateral osteophytes, only 6 exhibited small areas of full-thickness cartilage loss. ACL abnormalities varied: 27% normal, 3% ruptured, and 70% had intrasubstance high signal. Larger osteophytes in the medial (p = 0.012) and lateral (p = 0.002) intercondylar notch correlated significantly with ACL damage. All underwent medial UKA, with no evidence of areas with full lateral compartment cartilage loss intraoperatively. The MRI findings confirmed the radiographic diagnosis of bone-on-bone medial disease but highlights a range of findings in the ACL, lateral compartment, and patellofemoral joint compartment for patients who met the current x-ray and intraoperative indication for UKA. Further research is required to understand if these MRI changes will affect long-term outcomes.

Single Injection AAV2-FGF18 Gene Therapy Reduces Cartilage Loss and Subchondral Bone Damage in a Mechanically Induced Model of Osteoarthritis.

Osteoarthritis (OA) is a highly debilitating, degenerative pathology of cartilaginous joints affecting over 500 million people worldwide. The global economic burden of OA is estimated at $260-519 billion and growing, driven by aging global population and increasing rates of obesity. To date, only the multi-injection chondroanabolic treatment regimen of Fibroblast Growth Factor 18 (FGF18) has demonstrated clinically meaningful disease-modifying efficacy in placebo-controlled human trials. Our work focuses on the development of a novel single injection disease-modifying gene therapy, based on FGF18's chondroanabolic activity. OA was induced in Sprague-Dawley rats using destabilization of the medial meniscus (DMM) (3 weeks), followed by intra-articular treatment with 3 dose levels of AAV2-FGF18, rh- FGF18 protein, and PBS. Durability, redosability, and biodistribution were measured by quantifying nLuc reporter bioluminescence. Transcriptomic analysis was performed by RNA-seq on cultured human chondrocytes and rat knee joints. Morphological analysis was performed on knee joints stained with Safranin O/Fast Green and anti-PRG antibody. Dose-dependent reductions in cartilage defect size were observed in the AAV2-FGF18- treated joints relative to the vehicle control. Total defect width was reduced by up to 76% and cartilage thickness in the thinnest zone was increased by up to 106%. Morphologically, the vehicle- treated joints exhibited pronounced degeneration, ranging from severe cartilage erosion and bone void formation, to subchondral bone remodeling and near-complete subchondral bone collapse. In contrast, AAV2-FGF18-treated joints appeared more anatomically normal, with only regional glycosaminoglycan loss and marginal cartilage erosion. While effective at reducing cartilage lesions, treatment with rhFGF18 injections resulted in significant joint swelling (19% increase in diameter), as well as a decrease in PRG4 staining uniformity and intensity. In contrast to early-timepoint in vitro RNA-seq analysis, which showed a high degree of concordance between protein- and gene therapy-treated chondrocytes, in vivo transcriptomic analysis, revealed few gene expression changes following protein treatment. On the other hand, the gene therapy treatment exhibited a high degree of durability and localization over the study period, upregulating several chondroanabolic genes while downregulating OA- and fibrocartilage-associated markers. FGF18 gene therapy treatment of OA joints can provide benefits to both cartilage and subchondral bone, with a high degree of localization and durability.

Autologous minced cartilage implantation for focal cartilage lesions of the humeral capitellum

The goal of minced cartilage implantation (MCI) is to restore an intact cartilage surface in focal osteochondral lesions of the humeral capitellum. The indications for MCI are limited osteochondral lesions at the humeral capitellum, also at the head of the radius, with intact cartilage border as well as in situ or acompletely detached fragment, and free joint bodies (gradeII-gradeV according to Hefti). Contraindications for MCI are already concomitant or associated cartilage damage as well as bilateral osteochondral lesions and insufficient available cartilage material. After diagnostic arthroscopy to detect possible concomitant pathologies and to exclude already corresponding cartilage lesions, the arthroscope is flipped posterolaterally over the high posterolateral portal and asecond portal is created under visualization via the soft spot. Initially, debridement of the focal cartilage defect, assessment of the marginal zone, and/or salvage of free joint bodies. Using asmooth shaver and the filter provided, the partially or even completely detached cartilage fragment is unidirectionally fragmented under continuous suction. The remaining defect with astable marginal zone is cleanly curetted, and the joint is completely dried. The fragmented cartilage collected in the filter is bonded to amembrane using autologous conditioned plasma (ACP) and then arthroscopically applied to the defect via acannula, sealed using thrombin and fibrin. Postoperative immobilization in acast for at least 24 h is required. Afterwards, free exercise of the joint is possible, but no loading should be maintained for 6weeks. Return to sport after 3months. Good to very good clinical and MRI morphologic results are already evident in the short-term course. Prospective and retrospective multicenter studies are needed to evaluate future long-term results.

Advances in clinical repair techniques for localized knee cartilage lesions

To summarize the classic and latest treatment techniques for localized knee cartilage lesions in clinical practice and create a new comprehensive clinical decision-making process. The advantages and limitations of various treatment methods for localized knee cartilage lesions were summarized by extensive review of relevant literature at home and abroad in recent years. Currently, there are various surgical methods for treating localized knee cartilage injuries in clinical practice, each with its own pros and cons. For patients with cartilage injuries less than 2 cm 2 and 2-4 cm 2 with bone loss are recommended to undergo osteochondral autograft (OAT) and osteochondral allograft (OCA) surgeries. For patients with cartilage injuries less than 2 cm 2 and 2-4 cm 2 without bone loss had treatment options including bone marrow-based techniques (micro-fracture and ogous matrix induced chondrogenesis), autologous chondrocyte implantation (ACI)/matrix-induced ACI, particulated juvenile allograft cartilage (PJAC), OAT, and OCA. For patients with cartilage injuries larger than 4 cm 2 with bone loss were recommended to undergo OCA. For patients with cartilage injuries larger than 4 cm 2 without bone loss, treatment options included ACI/matrix-induced ACI, OAT, and PJAC. There are many treatment techniques available for localized knee cartilage lesions. Treatment strategy selection should be based on the size and location of the lesion, the extent of involvement of the subchondral bone, and the level of evidence supporting each technique in the literature.

MRI analysis of and factors related to knee injuries in amateur marathon runners.

Marathons are the most challenging form of running, and amateur athletes may be more prone to injury due to a lack of professional knowledge and instruction in running. To analyze the MRI manifestations of and factors related to knee injuries in amateur marathon runners. Data were collected from a hospital database of 105 qualified amateur marathon athletes (65 males,40 females), between May 2018 and December 2021. 1.5T MR: sagittal fs-PDWI, sagittal T1WI and sagittal 3D-DESS sequence. The MRI manifestations of knee joint injury were analyzed and evaluated by two radiologists. The inter-observer agreement on MRI readings was analyzed using the kappa coefficient, and binary logistic regression analysis was employed to identify factors associated with knee injuries. The overall prevalence of knee cartilage lesions, meniscus lesions and bone marrow edema among amateur marathon runners was 45.7%, 72.4%, and 49.5% respectively. Our analysis revealed that older age (OR = 1.135, P<0.001), higher BMI (OR = 1.236, P = 0.044), and slower pace (OR = 2.305, P = 0.017) were associated with increased risk of articular cartilage disease. Furthermore, older age (OR = 1.425, P<0.001) was identified as a risk factor for meniscal lesions, while older age (OR = 1.088, P = 0.002) was bone marrow edema. Notably, no significant correlation was observed between knee joint injuries of amateur marathon athletes and gender or the monthly running distance (P>0.05). The occurrence of knee injuries among amateur marathon athletes was highly prevalent, with the patellofemoral joint cartilage and posterior horn of medial meniscus being frequently affected areas. Moreover, age, BMI, running years and pace were significant risk factors of knee joint injury.

Role of MRI in Patellofemoral Pain Syndrome (Anterior Knee Pain)

Abstract Background MRI is a good diagnostic tool in identifying cartilage and soft tissue lesions as well as detecting underlying predisposing anatomical factors of patellar instability, it has a high specification for detecting the grades and the types of some of these diseases or factors that may predispose to them such as trochlear dysplasia and patella alta. Aim of the Work The aim of this study was to evaluate the role of MRI in diagnosis of Patellofemoralpain syndrome which is the most common cause of anterior knee pain. Patients and Methods This prospective study was done on patients referred from the orthopedic clinic to the department of radiodiagnosis, MRI unit at Ain Shams University hospitals.Thirty patients were included (18 females and 12 males) and their age ranged from 20 to 64 years. Conclusion This study shows that MRI is useful in detecting various predisposing anatomical factors of patellofemoral instability and associated lesions of knee joint thereby enabling orthopedic surgeons to treat joint pathology as well as correct underlying anatomical abnormality.

Paper 41: Does MR Arthrography Improve Evaluation of Patients with Posterior Shoulder Instability? An Analysis from the MOON Shoulder Instability Group

Objectives: Posterior shoulder instability is an uncommon injury, accounting for 2-12% of shoulder instability patients. Magnetic resonance imaging (MRI) is often utilized to non-invasively evaluate the joint for labral, cartilage, and bony injury. MR arthrography (MRA) may improve the evaluation of these intra-articular structures, but requires additional cost, time, and an invasive procedure. Moreover, its benefits for patients with posterior shoulder instability are unclear. Accurate imaging is critical in patients undergoing surgery because certain findings may influence the surgical approach. Thus, the purpose of this study is to compare the accuracy of MRA and non-enhanced MRI in detecting labral, chondral, and osseous lesions in patients with posterior shoulder instability. Methods: There were 291 patients with unilateral posterior shoulder instability who had preoperative MRA or MRI between 2006 and 2021 in the MOON database. Images were reviewed by a fellowship-trained musculoskeletal radiologist with 10+ years of experience and an orthopaedic surgeon. Evaluators were blinded to age, gender, medical history, MR report, and arthroscopic findings, but were aware of the patient's history of posterior shoulder instability. Examinations were evaluated for presence, location, morphology, and length of glenoid labral tears. Tear length and localization were noted using a standard clock face. The presence and size of humeral/glenoid osseous and cartilage lesions was also noted.Intraoperative findings from arthroscopic evaluation were documented by the surgeon using a standard response questionnaire. Diagnostic performance of standard MRA and MRI were evaluated using sensitivity and specificity with arthroscopic evaluation as the gold-standard. Chi-squared or Fisher’s exact tests were used to compare the sensitivities and specificities of MRA and MRI. Significance was defined as P &lt; 0.05. Results: 200 patients (69%) had MRA, while 91 patients had non-contrast MRIs of the shoulder. On imaging evaluation, 273 (94%) patients had labral tears with a mean tear size of 156º. 39 (13%) patients had humeral cartilage lesions, whereas 40 (14%) patients had glenoid cartilage lesions. 34 (12%) patients had glenoid bone loss greater than 5%. The mean glenoid bone loss was 12% (range, 5% - 26%). A reverse Hill-Sachs lesion was present in 35 (12%) patients. 16 (6%) patients had bipolar bone loss. The sensitivity for detection of labral tears was high for both MRA (0.95) and standard MRI (0.98) (Tables 1 and 2), though the specificity was low for both modalities (0.25 and 0.40, respectively). There was no difference in the sensitivities or specificities of the two imaging modalities in the detection of labral tears. MRA had a lower sensitivity than MRI in the detection of glenoid cartilage lesions (0.31 vs 0.88, p &lt; 0.001), but no difference was observed for specificity. There was no difference in the sensitivities and specificities of MRA and MRI for humeral cartilage lesions (p = 0.354).MRA had a higher sensitivity than MRI in assessing glenoid bone loss (0.78 vs 0.50, p &lt; 0.001), though there was no difference in specificity. There was no difference between imaging modalities in the evaluation of humeral bone loss (p = 1.000). Conclusions: In this multicenter study, MRA was the most commonly utilized preoperative advanced imaging study for patients with posterior shoulder instability. MRA had a higher sensitivity in detecting glenoid bone loss but lower sensitivity in detecting glenoid cartilage lesions compared to standard non-contrast MRI. There was no difference in diagnostic performance between MRA and MRI in the diagnosis of labral tears and humeral chondral and osseous lesions. MRA may provide an advantage over standard MRI in the evaluation of glenoid bone loss, which can influence the treatment plan for patients undergoing surgical management of posterior shoulder instability.

Poster 240: Radiographic and Patient-Reported Outcomes of Patellar Denovo Procedure in Shouldered Versus Unshouldered Patella Cartilage Lesions

Objectives: Unique challenges exist in treating patellar cartilage defects such as the contour of the articular surface and the high dynamic shear and compressive forces at the trochlear articulation. When considering restoration techniques osteochondral autograft or allograft can be used when the underlying bone is also involved but for isolated chondral defects, cell-based restoration is the standard of care. Previous literature has demonstrated that success of these cell-based therapies depends on a fully shouldered, stable rim of healthy cartilage to achieve repair stability. More recently, particulated juvenile articular cartilage (PJAC), minced hyaline cartilage from young donors, has demonstrated promising and practical results in the treatment of symptomatic articular defects of the patella and other surfaces. The newer cell-based techniques are more stable than previous options such as autologous chondrocyte implantation (ACI). The purpose of this study is to compare clinical outcomes of PJAC in patients with shouldered versus unshouldered full-thickness cartilage defects of the patella. We hypothesized that there will be no significant difference in short-term clinical outcomes and radiographic cartilage fill between shouldered and unshouldered lesions. Methods: A retrospective review of prospectively collected data was conducted on patients treated with PJAC for a full-thickness symptomatic patellar cartilage lesion between March 2014 and August 2019. Magnetic resonance imaging (MRI) was performed for all patients at 6, 12, and 24 months postoperatively and analyzed for percent fill, categorized by 0% to 33%, 34% to 66%, and 67% to 100% fill. Patient-reported outcome measures (PROMs) were obtained preoperatively and at 1, 2 and &gt;2 years postoperatively. Arthroscopic images were independently assessed, and cartilage defect characteristics were documented as shouldered or unshouldered by an orthopaedic surgery resident and an orthopaedic surgery sports fellow. Percent fill on MRI and clinical outcome scores (International Knee Documentation Committee, Kujala, Knee injury and Osteoarthritis Outcome Score – Physical Function Short-Form [KOOS-PS], Knee injury and Osteoarthritis Outcome Score – Quality of Life, The Hospital for Special Surgery Pediatric Functional Activity Brief Scale) were analyzed and correlated with the shouldered or unshouldered classification of the lesions. Results: Between March 2014 and August 2019, a total of 70 lesions in 65 patients were treated with PJAC for patellar cartilage lesions. The mean patient age was 26.6 years old (range, 14 – 51) and 76% (n = 53) were female. Twenty-five (36%) knees had undergone prior surgery and average symptom duration was 7.5 years. The average patellar lesion size was 277 mm2 (range, 77 – 800 mm2), the average number of allografts packets used was 2.4 (range, 1 – 5), and the average donor age was 46.1 months (range, 1 – 120). Arthroscopic pictures were available for 64 out of 70 lesions. There was perfect inter-rater reliability of whether the lesions were considered to have a continuous, stable rim (shouldered) or not (unshouldered). Thirty-two lesions were shouldered and the remaining 32 lesions were unshouldered according to their intraoperative pictures. Patients with shouldered lesions reported a significantly lower duration of symptoms than those with unshouldered lesions (5.29 ± 7.12 years vs.10.11 ± 9.85 years, p &lt; 0.05). Patients with shouldered lesions were also significantly more likely to have a prior knee surgery (p &lt; 0.05). Patients did not differ significantly by MRI percent fill in the shouldered versus unshouldered groups (Figure 1). There were no significant differences in baseline, 1-, or 2-year patient-reported outcomes based between patients with shouldered and unshouldered lesions (Table 1). The only statistically significant difference in outcomes was a lower score for KOOS-PS in the unshouldered group at &gt;2 years compared to the shouldered group (p &lt; 0.05), and in the change in KOOS-PS from baseline to 2-years between the 2 groups (p &lt;0.05). Conclusions: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. Historically, emphasis has been placed on having a stable, fully shouldered defect in order to achieve success of repair with microfracture or ACI. However, with the increased stability of newer cell-based treatments, these unshouldered cartilage lesions do well both clinically and radiographically. Our study found no significant differences between the shouldered and unshouldered groups with regard to both clinical outcomes as well as radiographic cartilage fill. This suggests that, with newer cartilage restoration techniques, whether a lesion is shouldered does not affect the outcomes achieved by these procedures. [Figure: see text]

Factors Affecting Choice of Surgical Treatment of Cartilage Lesions of the Knee: An Analysis of Data From 5143 Patients From the German Cartilage Registry (KnorpelRegister DGOU).

Symptomatic full-thickness cartilage lesions of the knee joint are considered an indication for cartilage repair surgery. Patient- and lesion-specific factors like age, nutritional status, etiology of defect, or integrity of corresponding joint surface remain controversial in indicating cartilage repair surgery. Furthermore, the selection of the most suitable cartilage repair technique for a specific cartilage lesion remains debatable. To evaluate indications and choice of treatment method for cartilage repair surgery, depending on patient- and lesion-specific data from the German Cartilage Registry. Cross-sectional study; Level of evidence, 3. A total of 6305 consecutive patients who underwent cartilage repair surgery of the knee evaluated and 5143 complete datasets were included in the analysis (follow-up rate, 81.5%). Patient-specific (age, body mass index, smoking status, previous operations, clinical leg axis) and lesion-specific (size, grading, location, etiology) data were provided by the attending surgeon at the time of surgery. Appropriate statistical tests were used to compare data depending on type and normality of data. Multivariable logistic regressions were calculated to investigate independent factors for the choice of specific cartilage repair techniques. The median size of treated cartilage lesions was 3.6 cm2, and most defects were of degenerative origin (54.8%). Of the registered patients, 39.2% were categorized as overweight and 19.6% as obese, while 23.3% were smokers. The most prevalently documented operative techniques were the autologous chondrocyte implantation (ACI) (52.4%), bone marrow stimulation (BMS) (17.3%), and BMS augmented with collagen scaffolds (9.3%). Independent factors that made the use of ACI more likely were bigger lesion size, previous surgery at the joint, and lesions located at the trochlea or the patella. On the contrary, BMS or augmented BMS were preferred in older patients, with damaged corresponding joint surface, and with more concomitant surgeries. Cartilage repair surgery was indicated irrespective of nutritional status, smoking status, or etiology of the treated lesion. ACI was the most prevalent technique and was preferred for younger patients and patellar lesions. While older patients with degenerative changes to the joint were not excluded from cartilage repair surgery, the use of ACI was restricted.

Poster 267: Relationship Between Sagittal Tibial Tubercle-Trochlear Groove Distance and Outcomes Following Cartilage Restoration for Patellofemoral Articular Cartilage Lesions

Objectives: Increased contact force in the patellofemoral (PF) joint is a known contributor to cartilage damage and pain. A tibial tubercle that is posterior to the trochlear groove may lead to aberrant loading and cartilage wear. The sagittal tibial-tubercle trochlear groove distance (sTT-TG), defined as the distance between the nadir of the trochlear groove and the most anterior aspect of the tibial tubercle, aids in quantifying the degree of risk of acquiring new lesions. However, the relationship between sTT-TG and patient-reported outcomes following surgery has not been assessed. Therefore, the purpose of this study is to assess the association between sTT-TG and post-operative outcomes in patients undergoing cartilage restoration procedures for PF articular cartilage lesions. Methods: A retrospective review of patients who underwent osteochondral allograft (OCA) transplantation or autologous chondrocyte implantation (ACI) at a single academic institution from 2010 to 2020 was conducted. Patients were included they underwent OCA or ACI for a high-grade (Outerbridge 3 or 4) articular cartilage lesion located in the patellofemoral joint (unipolar or bipolar), if they were between 18 and 50 years of age at the time of surgery, had magnetic resonance imaging (MRI) available, and had a minimum 2-year clinical follow-up. Demographic data such as age, sex, body mass index (BMI), as well as defect characteristics including size, number, and grade were collected. Before surgery, sTT-TG distance was measured independently on axial T2-weighted MRI sequences by two raters (Rater A and Rater B). Both raters measured the sTT-TG for the entire cohort at two different time points with a two-week time interval between each rater’s initial and follow-up measurements. The Interclass Coefficient (ICC) using a single measure, absolute agreement, two-way mixed effects model was used to test the intra-rater reliability of Rater A and Rater B; mean measures were used to assess the inter-rater reliability for the combined mean of the two rater’s measurements. Patients were surveyed to assess pain and satisfaction on a Visual Analog Scale (VAS) from 0 to 100. Functional outcomes were collected using the Knee Injury and Osteoarthritis Outcome Score (KOOS). The rate of return to sports, complications, and graft failure were also recorded [JT1]. An independent samples t-test was used to compare lesion size between the OCA and ACI group. Linear and logistic regression models accounting for age, sex, BMI, and sTT-TG distance were used to assess the relationship between sTT-TG and PROs. Results: A total of 76 patients, mostly female (61.8%), with a mean age of 31.9 ± 8.3 years, BMI of 26.8, and 60.6 ± 23.6-month follow-up were included. There were 37 (48.7%) patients that underwent OCA transplantation and 39 (51.3%) that underwent ACI. A total of 98 lesions were identified, with the majority (n = 93, 94.9%) being Grade 4. Overall, 54 patients had unipolar lesions and 22 had bipolar lesions. The mean defect size was 2.9 ± 1.4 cm2 and 3.5 ± 2.9 cm2 for the OCA and ACI groups (p = 0.459), respectively, with an overall mean lesion area of 3.2 ± 2.3 cm2. Intra-rater reliability for sTT-TG measurements at each time point was excellent for Rater A (ICC of 0.99 [0.986-0.994] p&lt;0.001) and Rater B (ICC of 0.99 [0.985-0.994]). Inter-rater reliability was excellent (ICC of 0.97 [0.955-.982] p&lt;0.001), with an overall mean sTT-TG of -4.98 ± 4.93 mm (range: -18.9, 5.7). On average, 48.7% (n = 37) of patients returned to sport and of those, 22.4% (n=17) returned to a similar or higher level of sport activity. Mean pain and satisfaction were 26.7 ± 25.1 and 73.8 ± 27.7, respectively. Collectively, the mean KOOS subscores were - KOOS symptoms: 71.4 ± 2.3, KOOS pain: 79.5 ± 2.0, KOOS sport: 60.2 ± 2.8, and KOOS QoL: 52.0 ± 2.6. When controlling for age, sex, BMI, and follow-up, sTT-TG was not predictive of RTS (p=0.706), pain (p=0.698), satisfaction (0.757), or any KOOS subscore (p&gt;0.05). Although, older age was associated with worse satisfaction (-0.819, 95% CI [-1.608,-0.03] and inferior KOOS pain (-0.606, 95% CI [-1.096,-0.116]), KOOS sport (-0.739, 95% CI [-1.445,-0.032]), and KOOS QoL (-0.786, 95% CI [-1.455,-0.117] p&lt;0.05). Conclusions: In this cohort of patients that underwent an OCA or ACI for PF cartilage lesions, sTT-TG was not predictive of post-operative patient reported functional outcomes or complications. These findings suggest that while a more posterior tibial tubercle (negative sTT-TG) may contribute to a higher incidence of cartilage pathology, patients can have favorable short-term outcomes following cartilage restoration with OCA or ACI.

Joint line convergence angle is the most associated alignment factor with the severity of medial knee osteoarthritis.

The purpose of this study was to evaluate the relationship between the joint line convergence angle (JLCA) and the severity of medial knee osteoarthritis (OA). We hypothesise that JLCA is the most associated factor with the severity of medial knee OA. This retrospective study included a total of 202 knees that underwent either high tibial osteotomy or medial meniscus repair/partial resection. Kellgren-Lawrence grade and hip-knee-ankle angle (HKAA), mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle (MPTA) and JLCA were assessed from preoperative radiographs. Medial meniscus extrusion (MME) was measured using preoperative magnetic resonance imaging. The International Cartilage Research Society (ICRS) grade on the medial femoral condyle and medial tibial plateau were also assessed. The relationships between JLCA and Kellgren-Lawrence grades and MME and ICRS grades were analysed using Spearman's correlation test and regression analysis. The JLCA was correlated with the Kellgren-Lawrence grade (R = 0.765, p < 0.001), MME (R = 0.638, p < 0.001), ICRS grade on the MFC (R = 0.586, p < 0.001) and the MTP (R = 0.586, p < 0.001). Regression analysis showed that age (p = 0.002) and JLCA (p < 0.001) were associated with Kellgren-Lawrence grade. Furthermore, JLCA was related to ICRS grade on the MFC (p < 0.001) and MTP (p < 0.001). The JLCA, reflecting radiological severity, meniscus status, and cartilage lesion, was the most associated alignment parameter in the severity of medial knee OA. The JLCA may be beneficial for quantitative assessment of medial knee OA. Level III, retrospective cohort study.

Poster 350: Do Early Radiographic Changes at 2 Years Predict Increased Pain at 6 Years After ACL Reconstruction?

Objectives: Even young patients without prior injury to the knee develop radiographic changes during the first two years after anterior cruciate ligament reconstruction (ACLR), but it’s unknown whether these early changes are predictive of increased pain over the next several years. The purpose of this study is to determine whether radiographic changes at 2 years are predictive of increased pain at 6 years while controlling for factors known to be predictive of worse pain after ACLR. We hypothesized that worse radiographic changes would not be predictive of increased pain. Methods: Patients were part of a nested cohort who underwent ACLR for an athletic injury, had no prior injury to their knee, and were 35 years of age or younger at 2-year follow-up. These patients underwent standardized posteroanterior semi-flexed knee radiographs using the metatarsophalangeal (MTP) positioning technique at 2 years and completed questionnaires at baseline (at time of enrollment, just prior to their ACL surgery), 2 years, and 6 years. These questionnaires included demographic questions, the SF-36, the Knee Injury and Osteoarthritis Outcome Score (KOOS), and the Marx Activity Level Scale. Surgeons completed an intraoperative data form that included physical examination and arthroscopy findings and treatments administered to the knee. Radiographs were graded by 2 graders using the semiquantitative atlas-based Osteoarthritis Research Society International (OARSI) scoring system, where scores of 0-3 are assigned in the medial and lateral compartments for features including osteophytes, joint space narrowing, sclerosis, and bony attrition. A directed acyclic graph (DAG) was used to plan the statistical models to assess the direct effect of radiographic change on pain at 6 years. A model was built using proportional odds logistic regression, and missing data were imputed using multivariate imputation via chained equation (MICE) for 20 cycles. The model controlled for baseline pain, age, sex, body mass index, years of education, baseline Marx, baseline SF-36, medial and lateral meniscus treatment, presence of cartilage lesion(s), allograft use, and incidence of subsequent surgery before 2 years. Results: A total of 421 subjects were included in the analysis cohort. The median age was 18 years at the time of enrollment (interquartile range [IQR]16-21 years), and 216 (51.3%) were female. 297 subjects (70.5%) had a normal medial meniscus, 85 (20.2%) had a repair, and 39 (9.3%) had a partial meniscectomy. A total of 257 subjects (61.0%) had a normal lateral meniscus, 30 (7.1%) had a repair, and 134 (31.8%) had a partial meniscectomy. 107 subjects (25.4%) had at least 1 Outerbridge grade 2 or worse cartilage lesion. Fifty-three subjects (12.6%) had subsequent surgery prior to their 2-year follow-up. The median total radiographic score on the 2-year radiographs was 4 (IQR 2.0-5.5) and ranged from 0 to 12.5. Median KOOS pain (where 100 = no pain) was 75 (IQR 63.9 to 86.1) at baseline, 96.9 (IQR 91.7 to 100) at 2 years, and 97.2 (IQR 88.9 to 100) at 6 years. Marx activity level (where 16 points = highest activity level) at baseline was 16 (IQR 12 to 16). After controlling for the other variables in the model, subjects with a total radiographic score of 5.5 had 6% increased odds of having increased KOOS pain at 6 years compared to patients with a total radiographic score 2, but this effect was not statistically significant (odds ratio = 1.06, 95% CI, 0.79-1.42, p = .698). Greater baseline pain (odds ratio 1.41, 95% CI 1.06-1.86, p = .018) and subsequent surgery prior to 2 years (odds ratio 0.52, 95% CI, 0.3-0.93, p = .026) were both statistically significant predictors of worse pain at 6-year follow-up. Conclusions: Even young, active patients begin to develop radiographic changes by 2 years after ACLR; however, these changes are not associated with increased pain up to 6 years postoperatively. This information is important for counseling patients who may be concerned about radiographic changes that are seen on x-rays obtained during the first few years after ACLR. In addition, this study suggests that treatment decisions around the time of surgery that can minimize baseline pain and decrease the incidence of subsequent surgery may improve patient pain levels at 6 years postoperatively.