Osteochondral Abnormalities Research Articles

Unleashing the Healing Power of Mesenchymal Stem Cells for Osteochondral Abnormalities

Unleashing the Healing Power of Mesenchymal Stem Cells for Osteochondral Abnormalities

Mice heterozygous for an osteogenesis imperfecta-linked MBTPS2 variant display a compromised subchondral osteocyte lacunocanalicular network associated with abnormal articular cartilage.

Missense variants in the MBTPS2 gene, located on the X chromosome, have been associated with an X-linked recessive form of osteogenesis imperfecta (X-OI), an inherited bone dysplasia characterized by multiple and recurrent bone fractures, short stature, and various skeletal deformities in affected individuals. The role of site-2 protease, encoded by MBTPS2, and the molecular pathomechanism underlying the disease are to date elusive. This study is the first to report on the generation of two Mbtps2 mouse models, a knock-in mouse carrying one of the disease-causative MBTPS2 variants (N455S) and a Mbtps2 knock-out (ko) mouse. Because both loss-of-function variants lead to embryonic lethality in hemizygous male mutant mice, we performed a comprehensive skeletal analysis of heterozygous Mbtps2+/N455S and Mbtps2+/ko female mice. Both models displayed osteochondral abnormalities such as thinned subchondral bone, altered subchondral osteocyte interconnectivity as well as thickened articular cartilage with chondrocyte clustering, altogether resembling an early osteoarthritis (OA) phenotype. However, distant from the joints, no alterations in the bone mass and turnover could be detected in either of the mutant mice. Based on our findings we conclude that MBTPS2 haploinsufficiency results in early OA-like alterations in the articular cartilage and underlying subchondral bone, which likely precede the development of typical OI phenotype in bone. Our study provides first evidence for a potential role of site-2 protease for maintaining homeostasis of both bone and cartilage.

Osteochondral Tissue Engineering Dilemma: Scaffolding Trends in Regenerative Medicine.

Orthopedic surgeons face a lot of difficulties in managing and repairing osteochondral defects. Damaged articular cartilage and the subchondral bone underneath are both present in osteochondral defects. The demands of the bone, cartilage, and the contact between the bone and the cartilage must be taken into consideration while repairing an osteochondral defect. Only palliative, not curative, therapeutic interventions are now available for the healing of osteochondral abnormalities. With its ability to successfully rebuild bone, cartilage, and the junction between bone and cartilage, tissue engineering has been recognized as an effective substitute. In correlation, mechanical stress and physical processes are commonly applied to the osteochondral area. Therefore, the ability of chondrocytes and osteoblasts to regenerate is influenced by bioactive molecules and the physicochemical characteristics of the surrounding matrix. The treatment of osteochondral disorders is said to benefit from the use of stem cells as an alternative intervention. In the field of tissue engineering, various approaches have been used such as the direct implantation of scaffolding materials at the site of tissue injury in patients, either alone or loaded with cells and bioactive molecules at the target site to imitate the natural extracellular matrix. Despite the extensive use and advancements of tissue-engineered biomaterials such as natural and synthetic polymer-based scaffolds, their repair capacity is limited due to challenges in combating antigenicity, designed to simulate in vivo microenvironment, and conducting mechanical or metabolic characteristics comparable to native organs/tissues. This study explores numerous osteochondral tissue engineering methodologies focusing on scaffold design, material varieties, manufacturing techniques, and functional features. This review is focused on recent breakthroughs in bioactive scaffolds that aid osteogenic and chondrogenic differentiation for bone and cartilage repair. The topic will cover fundamental anatomy, osteochondral repair methodologies and obstacles, cell selection, biochemical variables, and bioactive materials, as well as the design and manufacture of bioactive scaffolds. Additionally, we focus on the concept and construction of decellularized scaffolds, and the fabrication of dECM scaffolds in tissue engineering from various skin, bone, nerve, heart tissue, lung, liver, and kidney, and their application in osteochondral regeneration.

MRI of the Elbow: How to Do It.

The diagnostic cascade for elbow complaints starts with the physical examination and radiographs that already can clarify or rule out many causes. Depending on the suspected pathology, additional imaging is necessary. Magnetic resonance imaging (MRI) has the advantage of accurately demonstrating a broad spectrum of diseases. The main indication for noncontrast MRI of the elbow is chronic epicondylitis. For magnetic resonance (MR) arthrography, it is suspected chondral and osteochondral abnormalities. Indirect MR arthrography is an option when direct arthrography is not practicable. MR arthrography of the elbow with traction is feasible, with promising results for the assessment of the radiocapitellar cartilage.

Osteochondral Lesions of the Knee: Differentiating the Most Common Entities at MRI.

Several pathologic conditions may manifest as an osteochondral lesion of the knee that consists of a localized abnormality involving subchondral marrow, subchondral bone, and articular cartilage. Although understanding of these conditions has evolved substantially with the use of high-spatial-resolution MRI and histologic correlation, it is impeded by inconsistent terminology and ambiguous abbreviations. Common entities include acute traumatic osteochondral injuries, subchondral insufficiency fracture, so-called spontaneous osteonecrosis of the knee, avascular necrosis, osteochondritis dissecans, and localized osteochondral abnormalities in osteoarthritis. Patient demographics, the clinical presentation, and the role of trauma are critical for differential diagnosis. A localized osteochondral defect can be created acutely or can develop as an end result of several chronic conditions. MRI features that aid in diagnosis include the location and extent of bone marrow edema, the presence of a fracture line, a hypointense area immediately subjacent to the subchondral bone plate, and deformity of the subchondral bone plate. These findings are essential in diagnosis of acute traumatic injuries, subchondral insufficiency fracture, and its potentially irreversible form, spontaneous osteonecrosis of the knee. If the lesion consists of a subchondral region demarcated from the surrounding bone, the demarcation should be examined for completeness and the presence of a "double-line sign" that is seen in avascular necrosis or findings of instability, which are important for proper evaluation of osteochondritis dissecans. Subchondral bone plate collapse, demonstrated by the presence of a depression or a fluid-filled cleft, can be seen in advanced stages of both avascular necrosis and subchondral insufficiency fracture, indicating irreversibility. Once the diagnosis is established, it is important to report pertinent MRI findings that may guide treatment of each condition. ©RSNA, 2018 An earlier incorrect version of this article appeared online. This article was corrected on August 23, 2018.

Vessel architecture in human knee cartilage in children: an in vivo susceptibility-weighted imaging study at 7 T

ObjectivesTo evaluate the clinical feasibility of ultrahigh field 7-T SWI to visualize vessels and assess their density in the immature epiphyseal cartilage of human knee joints.Methods7-T SWI of 12 knees (six healthy volunteers, six patients with osteochondral abnormalities; mean age 10.7 years; 3 female, 9 male) were analysed by two readers, classifying intracartilaginous vessel densities (IVD) in three grades (no vessels, low IVD and high IVD) in defined femoral, tibial and patellar zones. Differences between patients and volunteers, IVDs in different anatomic locations, differences between cartilage overlying osteochondral abnormalities and corresponding normal zones, and differences in age groups were analysed.ResultsInterrater reliability showed moderate agreement between the two readers (κ = 0.58, p < 0.001). The comparison of IVDs between patients and volunteers revealed no significant difference (p = 0.706). The difference between zones in the cartilage overlying osteochondral abnormalities to corresponding normal zones showed no significant difference (p = 0.564). IVDs were related to anatomic location, with decreased IVDs in loading areas (p = 0.003). IVD was age dependent, with more vessels present in the younger participants (p = 0.001).ConclusionsThe use of SWI in conjunction with ultrahigh field MRI makes the in vivo visualization of vessels in the growing cartilage of humans feasible, providing insights into the role of the vessel network in acquired disturbances.Key Points• SWI facilitates in vivo visualization of vessels in the growing human cartilage.• Interrater reliability of the intracartilaginous vessel grading was moderate.• Intracartilaginous vessel densities are dependent on anatomical location and age.

Imaging of haemophilic arthropathy in growing joints: pitfalls in ultrasound and MRI.

The purpose of this review was to summarize the current knowledge on the utilization of magnetic resonance imaging (MRI) and ultrasound (US) for assessing arthropathy in children and adolescents with haemophilia and to recognize the limitations of each imaging modality and pitfalls in the diagnosis of soft tissue and osteochondral abnormalities. Awareness of MRI and US limitations and pitfalls in the assessment of joints in persons with haemophilia is essential for accurate diagnosis and optimal management of haemophilic arthropathy.

Correlating clinical and radiological assessment of joints in haemophilia: results of a cross sectional study.

This study was undertaken to determine the correlation between the radiological changes in haemophilic arthropathy [X-ray, Ultrasound (US) and MRI] and clinical assessment as determined by the Hemophilia Joint Health Score (HJHS); and to document the US and MRI changes in joints that appear normal on plain X-ray and clinical evaluation. Of 55 study joints (22 knees and 33 ankles) in 51 patients with haemophilia/von Willebrand disease, with a median age of 15 years (range: 5-17) were assessed using X-rays (Pettersson score) and clinical examination (HJHS) at two centres (Toronto, Canada; Vellore, India). MRI and ultrasonographic scoring was done through a consensus assessment by imagers at both centres using the IPSG MRI and US scores. The HJHS had a good correlation with the Pettersson score (rs = 0.66). Though the HJHS had moderate correlation with the osteochondral component of the MRI and US scores (rs 0.51, 0.45 respectively), its correlation with the soft tissue component was poor (rs 0.19; 0.26 respectively). Of the 18 joints with a Pettersson score of zero, 88.9% had changes that were detected clinically by the HJHS. Osteochondral abnormalities were identified in 38.9% of these joints by the MRI, while US images of the same joints were deemed abnormal in 83.3% by the current criteria. US identified haemosiderin and other soft tissue changes in all of the joints, while the same changes were noted in 94.4% of these joints on MRI. There were four joints with a HJHS of zero, all of which had soft tissue changes on MRI (score 1-7) and US (score 2-7). Osteochondral changes were detected in three of these joints by US and in 2 by MRI. There were four joints with an MRI score of 0-1 that had significant US scores (3-5) and HJHS scores (0-6). US and MRI are able to identify pathological changes in joints with normal X-ray imaging and clinical examination. However, further studies are required to be able to differentiate early abnormalities from normal. Clinical (HJHS) and radiological assessment (US/MRI) provide complimentary information and should be considered conjointly in the assessment of early joint arthropathy.

Role of magnetic resonance imaging in the evaluation of articular cartilage in painful knee joint

<b>Aim:</b> The aim of this study was to determine the role of the magnetic resonance imaging (MRI) in patients with atraumatic knee pain. <b>Background and Objectives:</b> Knee pain is one of the most common problems faced by people from time immemorial. There is a wide range of disease ranging from traumatic to degenerative causing knee pain in which articular cartilage is involved. Over the past 15 years, MRI has become the premier, first-line imaging study that should be performed in the evaluation of the painful knee in particular in tears of menisci, cruciate and collateral ligaments, osteochondral abnormalities (chondromalacia, osteoarthritis and osteochondral defects), synovial cysts and bone bruises. MRI, by virtue of its superior soft-tissue contrast, lack of ionizing radiation and multiplanar capabilities, is superior to more conventional techniques for the evaluation of articular cartilage. <b>Materials and Methods:</b> A prospective study was carried out on 150 patients in the Department of Radio-diagnosis, Padmashree Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pimpri, Pune over a period of 2 years from June 2011 to May 2013. Patients having fracture or dislocations of the knee joint were also excluded from the study. Detailed clinical history, physical and systemic examination findings of all patients were noted in addition to the laboratory investigations. All patients were subjected to radiograph of knee anterior-posterior and lateral view. MRI was performed with Siemens 1.5 Tesla MAGNETOM Avanto machine. <b>Results:</b> In our study of 150 patients with knee pain, articular cartilage defect was found in 90 patients (60%). Out of 90 patients with articular cartilage defect, 30 patients (20%) had full thickness cartilage defects. Subchondral marrow edema was seen beneath 30 patients (20%) with articular cartilage defects. 32 patients (21.1%) had a complex or macerated meniscal tear. Complete anterior cruciate ligament tear was found in seven patients. Joint effusions were detected in 70% (105) of the knees. Large Baker cysts were observed in 6.1% of the knees. <b>Conclusion:</b> In conclusion, individual with acute or chronic knee pain without any definite history of trauma should be subjected to MRI study of the knee provided radiographs are non-informative or non-diagnostic. The study not only outlines the tendons, ligament and cartilage status, but also demonstrates subtle underlying bony pathologies causative for patient complaints.

Arthroscopic treatment of osteochondral lesion of olecranon

Osteochondral lesions (OCLs) are rarely seen in the elbow joint. These lesions are most commonly seen in the capitellum and radial head [5]. Although their exact mechanism is not very well understood, repetitive microtrauma and ischaemia are accepted as the two main aetiological factors [1, 5]. The term ‘‘osteochondral lesion’’ was used in this text, because it seems recently to cover all the definitions used for osteochondral abnormalities. Generally, the treatment aims for the pain relief and the return of the patient to the previous level of activities. Conservative follow-up and different surgical methods are possible for the treatment. The surgical treatment options include arthroscopic debridement, drilling, fragment excision or fixation, and osteochondral autografting. Among surgical modalities, arthroscopic excision of the fragments and subchondral abrasion or drilling of the lesion resulted in satisfactory short-term clinical outcomes [1, 2]. Case report

Ressonância magnética da osteonecrose do joelho: estudo de 19 casos

OBJETIVO: Descrever os achados epidemiológicos, clínicos e de ressonância magnética da osteonecrose das porções distal do fêmur e proximal da tíbia. MATERIAIS E MÉTODOS: Avaliação de 19 pacientes (12 mulheres e 7 homens), sem história prévia de fatores causais, com achados à ressonância magnética sugestivos de osteonecrose do platô tibial ou côndilo femoral. RESULTADOS: Verificou-se a presença de anormalidades osteocondrais em 63,1% dos casos e em 73,6% destes houve associação com lesão meniscal ipsilateral. Houve também importante associação com edema na medular óssea em correspondência (grau III em 16 casos). CONCLUSÃO: A ressonância magnética demonstrou ser um método não invasivo com boa sensibilidade no diagnóstico da osteonecrose do joelho, bem como das lesões associadas, sendo mais frequente nas mulheres (63% dos casos).

Osteochondral lesions of the humeral trochlea in the young athlete

The purpose of this study was to characterize the variety of osteochondral abnormalities of the humeral trochlea in the pediatric athlete. Patients with trochlear abnormalities were identified through keyword search of radiology dictations from 1999 to 2007. The patient's medical record, imaging studies, and surgical reports were reviewed. The osteochondral lesions were categorized based on the imaging appearance. Surgical results were reviewed in conjunction with the imaging findings. Eighteen patients were identified. Trochlear lesions were stratified into two imaging groups: Osteochondral injury/osteochondritis dissecans (OCD) vs. avascular necrosis (AVN). The osteochondral injury group was stratified into medial and lateral trochlear abnormalities. The medial lesions (n = 3) were small (<6 mm) and were located on the posterior articular surface of the medial trochlea. The lateral lesions (n = 10) were larger (10-14 mm), circumscribed, and were located on the posterior inferior aspect of the lateral trochlea. Trochlear AVN (n = 5) affected development of the lateral trochlea (type A) or both the medial and lateral aspects of the trochlea (type B). AVN occurred exclusively in athletes with history of remote distal humeral fracture. Seven of the 18 patients underwent elbow arthroscopy. Surgical findings and treatment regimens are summarized. Trochlear lesions should be considered in throwing athletes presenting with medial elbow pain and flexion contracture/extension block. Medial trochlear osteochondral injuries may result from posteromedial olecranon abutment. Lateral OCD lesions occur in a characteristic vascular watershed zone resulting from the unique blood supply of the trochlea. Trochlear AVN may be unmasked years following treated distal humeral fracture when the athletic demands upon the adolescent elbow increase, revealing the altered growth and biomechanics.

Reliability of progressive and additive MRI scoring systems for evaluation of haemophilic arthropathy in children: Expert MRI Working Group of the International Prophylaxis Study Group

Effective treatment of haemophilic arthropathy requires a detailed evaluation of joint integrity. Methodological assessment of magnetic resonance imaging (MRI) scores are needed to assure reproducibility of measurements when comparing results of clinical trials conducted in different centres. We compared the reliability of two MRI scoring systems for assessment of haemophilic arthropathy: one progressive system that displays the most severe change and one additive system that depicts osteochondral and soft tissue-related changes. A total of 47 1.5 T MRI examinations of knees (n = 21) and ankles (n = 26) of 42 haemophilic boys, age range, 22 months to 18 years, performed at different centres (Toronto, n = 20, Europe, n = 12 and Denver, n = 15) were independently reviewed by four radiologists at two occasions. Twenty-two examinations were from children <9 years and 25 from children >/=9. Sagittal and coronal gradient-echo (MPGR, 3D FLASH with fat saturation, GRASS) images were obtained. The MRI examinations of the ankle and knee studies presented with osteochondral abnormalities in 38.5% and 23.8% of the cases respectively. The two scoring systems demonstrated an excellent inter-reader [progressive, 0.88; additive (A, e, s and h components), 0.86] and intra-reader [progressive, 0.92; additive (A, e, s and h components), 0.93] reliability using intraclass correlation coefficients (ICCs). Although ICCs were slightly higher for knees when compared with ankles, and for older children when compared with younger children, all values fell within excellent inter- and intra-reader reliability categories. The two MRI scoring systems demonstrated a comparable reliability. This result constitutes the basis for further development of a combined MRI scoring system for assessment of haemophilic arthropathy, which incorporates progressive and additive components.

MR appearance of SONK-like subchondral abnormalities in the adult knee: SONK redefined.

To investigate the MR characteristics of SONK-like (spontaneous osteonecrosis of the knee) subchondral abnormalities in the adult atraumatic knee and to recategorize these patients into two subgroups: a subacute to chronic process associated with osteoarthritis and an acute process associated with insufficiency fractures. We retrospectively examined the knee MRIs of 39 patients with non-specific interpretations of osteochondral abnormalities. There were a total of 52 subchondral lesions without any known traumatic event and no prior surgery. All lesions evaluated had MR features previously ascribed to SONK. Several MR characteristics were then assessed: presence or absence of a line, size, zonal location, T1 and T2 signal, associated marrow edema, associated ipsilateral meniscal tear, and associated ipsilateral cartilage defects. The abnormalities with linear components (insufficiency fractures) tended to be larger (P<0.01) and were associated with a severe amount of marrow edema (P<0.0001) consistent with an acute process. The non-linear abnormalities were more associated with cartilage defects (P=0.01) and less marrow edema consistent with osteoarthritis and a subacute to chronic process. This association of SONK-like abnormalities with osteoarthritis and insufficiency fractures casts doubt on the validity of the term "spontaneous osteonecrosis" as it is currently applied, and further investigation into the separate etiologies of these subchondral marrow lesions is needed.

Radiographic development of osteochondral abnormalities, in the hock and stifle of Dutch Warmblood foals, from age 1 to 11 months.

In a longitudinal study the hocks and stifles of Dutch Warmblood foals were radiographed at age 1 month and subsequently at intervals of 4 weeks. Forty-three foals were radiographed until age 5 months and 19 foals until age 11 months. The chance for the development of osteochondrosis was enhanced by using only offspring from diseased sires with radiographically proven OC at either the intermediate ridge of the distal tibia or the lateral ridge of the femoral trochlea. The radiographic appearances of the intermediate ridge of the distal tibia, the distal aspect of the lateral trochlear ridge of the talus and the midregion of the lateral ridge of the femoral trochlea were classified on a 0-4 scale using a standardised radiographic classification. At age 1 month the appearance of the intermediate ridge of the distal tibia was frequently abnormal (grades 1-3: 67%; grade 4: 1%). Abnormal appearances of the distal aspect of the lateral trochlear ridge of the talus were less common (grades 1-3: 25%; grade 4: 6%). The midregion of the lateral ridge of the femoral trochlea was predominantly normal (grade 0: 98%; grade 1: 2%). Initial abnormalities of the intermediate tibial ridge showed a marked tendency for regression. Progression was less common. Normal appearances rarely turned into abnormal. Only 18% of the hocks were still abnormal at this site at age 11 months. Abnormalities of the distal aspect of the lateral trochlear ridge of the talus showed a strong tendency towards resolution. Progression never occurred. Normal appearances seldom turned into abnormal. Only 3% of the hocks were still abnormal at this site at age 11 months. For both predilection sites in the hock normal and abnormal appearances were permanent from age 5 months. In the stifle, abnormal appearances of the midregion of the lateral ridge of the femoral trochlea became obvious from age 3 or 4 months. Subsequent progression was usually followed by regression and resolution, the appearance returned in most cases to normal at age 8 months. At 5 months, 20% of the stifles were abnormal, but at 11 months this percentage had decreased to 3%. Normal and abnormal appearances were permanent from age 8 months. Osteochondrosis of the main predilection sites in the hock and stifle develops very early in life. The majority of the lesions were temporary, the 'age of no return' was 5 months for the hock and 8 months for the stifle.

Coronal fat suppression fast spin echo images of the knee: Evaluation of 202 patients with arthroscopic correlation

We optimized fat-suppressed fast spin echo (FS-FSE) parameters for coronal imaging of the knee and then evaluated the technique in a clinical setting. Five volunteers and 12 patients were used to evaluate various repetition (TR), echo (TE), and echo train lengths (ETL). Then, 202 patients underwent both knee MR imaging using coronal plane FS-FSE and arthroscopy. The coronal FS-FSE images were compared with radial multiplanar gradient-recalled echo (MPGRE), axial T 1-weighted SE, and parasagittal double echo SE images. Proton density images ( 2000 19 ) with an ETL of 2 best depicted the menisci, ligaments, and capsules. The conspicuity of osteochondral abnormalities depicted by the coronal FS-FSE imaging was significantly higher than for axial T 1-weighted SE ( p < .003) and parasagittal double echo SE images ( p < .003). The accuracy of the coronal FS-FSE imaging for medial and lateral meniscal tears was 91.6% and 87.6%, respectively. Combined imaging interpretation of the coronal FS-FSE, axial T 1-weighted SE, and radial MPGRE imaging improved the accuracy for meniscal tears slightly over any sequence used alone, but the difference was not statistically significant. Fourteen capsular injuries were demonstrated by the coronal FS-FSE imaging. FS-FSE imaging in the coronal plane is a useful complementary sequence in MR examinations of the knee for the evaluation of meniscal tears, capsular injuries, and osteochondral abnormalities.

Evaluation of articular cartilage: radiographic and cross-sectional imaging techniques.

Many diagnostic modalities may be used to evaluate articular cartilage. Plain radiography remains the preferred initial study for cartilage evaluation, although even specialized views such as weight-bearing, tunnel, and flexion lateral projections are insensitive in the detection of early cartilage loss. Compared with newer modalities, conventional arthrography has limited capacity for the assessment of cartilage. Computed tomography performed after intraarticular injection of contrast material (ie, CT arthrography) has improved accuracy but is essentially limited to the axial plane. Magnetic resonance (MR) imaging, with its superb soft-tissue contrast and multiplanar capabilities, has shown promise in depicting articular cartilage. Cartilage is best depicted when an "arthrogram effect" is present, achieved with T2-weighted spin-echo imaging, with some gradient-echo pulse sequences, and when intraarticular contrast material is used. If performed with such techniques, MR imaging is the method of choice for evaluating specific cartilage loss, osteochondritis dissecans, and other osteochondral abnormalities.