A Magnetic Resonance Imaging-Based Staging System for Osteochondritis Dissecans of the Elbow: A Validation Study Against the International Cartilage Repair Society Classification

Lawrence J, Polousky JD, Saper M, Uquillas C, Nissen CW, Kostyun RO, Albright J, Bae D, Bohn D, Chan C, Crepeau A, Edmonds E, Fabricant P, Ganley T, Little K, Lee Pace J, Pacicca D, Pennock A, Saluan P, Shea K, Wall E, Wilson P, Nissen CW. MRI Features That Contribute to Decision-Making for Treatment of Capitellar OCD Lesions: An Expert Consensus Using the Delphi Method

Background

Most healthcare providers utilize magnetic resonance imaging (MRI) to assist in diagnosing and treating osteochondritis dissecans (OCD) of the capitellum. However, consensus on imaging features that portend clinically relevant information in the care of these lesions has not been determined.

Purpose

To conduct a survey on the MRI features of a capitellar OCD that are salient for clinical decision-making using a classic Delphi protocol.

Study Design

A consensus statement.

Methods

Invitations to participate were sent to 33 healthcare providers identified as capitellar OCD experts. A classic 3-round survey method was used to gather agreement and consensus on the level of importance for clinical decision-making on 33 MRI features. A concise list of features that guide decision-making on the stability of an OCD lesion and the ability of an OCD lesion to heal with nonoperative care was also identified. Agreement and consensus were determined a priori as ≥66%.

Results

Of the 33 identified experts, 20 agreed to participate, and 17 (52%) completed all 3 rounds. Of the 33 MRI features evaluated, 17 reached agreement as important for clinical decision-making by the experts. Consensus was reached for a concise list of MRI features that were significant to decision-making (94%), suggestive of a stable lesion (100%), had the potential to heal with nonoperative treatment (94%), were suggestive of an unstable lesion (100%), and had low potential to heal with nonoperative treatment (88%).

Conclusion

This 3-round Delphi process produced consensus on clinically relevant MRI features that contribute to clinical decision-making for capitellar OCD. The results of this study will be used as the basis for an interrater reliability assessment of the identified salient features, creating the foundation for developing a reliable MRI assessment tool rooted in clinical experiences. The development of a standardized assessment of capitellar OCD is intended to improve clinical practice and patient outcomes.

Osteochondritis dissecans of the elbow: recent evolution of pathogenesis, imaging, and treatment modalities

Background

The etiology and pathogenesis of osteochondritis dissecans (OCDs) lesions remain controversial.

Methods

This review presents the recent evolution about the healing, imaging, pathogenesis, and how to treat OCD of the capitellum in overhead athletes.

Results

Compressive and shear forces to the growing capitellum can cause subchondral separation, leading to OCD, composed of 3 layers: articular fragment, gap, and underlying bone. Subchondral separation can cause ossification arrest (stage IA), followed by cartilage degeneration (stage IB) or delayed ossification (stage IIA), occasionally leading to osteonecrosis (stage IIB) in the articular fragment. Articular cartilage fracture and gap reseparation make the articular fragment unstable. The mean tilting angle of capitellar OCD is 57.6 degrees in throwers. Anteroposterior radiography of the elbow at 45 degrees of flexion (APR45) can increase the diagnostic reliability, showing OCD healing stages, as follows: I) radiolucency, II) delayed ossification, and III) union. Coronal computed tomography and magnetic resonance imaging with an appropriate tilting angle can also increase the reliability. MRI is most useful to show the instability, although it occasionally underestimates. Sonography contributes to detection of early OCD in adolescent throwers on the field. OCD lesions in the central aspect of the capitellum can be more unstable and may not heal. Cast immobilization has a positive effect on healing for stable lesions. Arthroscopic removal provides early return to sports, although a large osteochondral defect is associated with a poor prognosis. Fragment fixation, osteochondral autograft transplantation, and their hybrid technique have provided better results.

Discussion

Further studies are needed to prevent problematic complications of capitellar OCD, such as osteoarthritis and chondrolysis.

Osteochondritis Dissecans of the Elbow in Overhead Athletes: A Comprehensive Narrative Review

Osteochondritis dissecans (OCD) of the elbow mainly occurs in overhead athletes (OHAs). This narrative review aimed to comprehensively analyze the epidemiological data, etiological factors, clinical and imaging features, treatment options, and outcomes of OHAs with the diagnosis of elbow OCD. A literature search was performed in PubMed/MEDLINE, Scopus, and Web of Science. Individuals with elbow OCD were usually 10-17 years of age with incidence and prevalence varying between studies, depending on the sport activity of the patients. The etiology of OCD lesions is multifactorial, and the main causes are believed to be repetitive trauma, the biomechanical disproportion of the articular surfaces, poor capitellar vascular supply, and inflammatory and genetic factors. Athletes usually presented with elbow pain and mechanical symptoms. The mainstay for the diagnosis of elbow OCD is MRI. The treatment of elbow OCD lesions should be conservative in cases of stable lesions, while various types of surgical treatment are suggested in unstable lesions, depending mainly on the size and localization of the lesion. The awareness of medical practitioners and the timely diagnosis of OCD lesions in OHAs are key to favorable outcomes.

Accessibility of osteochondral lesion at the capitellum during elbow arthroscopy: an anatomical study

INTRODUCTION

Osteochondrosis dissecans (OCD) at the capitellum is a common pathology in young patients. Although arthroscopic interventions are commonly used, there is a lack of information about the accessibility of the defects during elbow arthroscopy by using standard portals.

MATERIALS AND METHODS

An elbow arthroscopy using the standard portals was performed in seven fresh frozen specimens. At the capitellum, the most posterior and anterior cartilage surface reachable was marked with K-wires. Using a newly described measuring method, we constructed a circular sector around the rotational center of the capitellum. The intersection of K-wire "A" and "B" with the circular sector was marked, and the angles between the K-wires and the Rogers line, alpha angle for K-Wire "A" and beta angle for K-wire "B", and the corridor not accessible during arthroscopy was digitally measured.

RESULTS

On average, we found an alpha angle of 53° and a beta angle of 104°. Leaving a sector of 51° which was not accessible via the standard portals during elbow arthroscopy.

CONCLUSION

Non-accessible capitellar lesions during elbow arthroscopy should be considered preoperatively, and the informed consent discussion should always include the possibility of open procedures or the use of flexible instruments.

LEVEL OF EVIDENCE: 4

Application of quantitative T1, T2 and T2* mapping magnetic resonance imaging in cartilage degeneration of the shoulder joint

To investigate and compare the values of 3.0 T MRI T1, T2 and T2* mapping quantification techniques in evaluating cartilage degeneration of the shoulder joint. This study included 123 shoulder joints of 119 patients, which were scanned in 3.0 T MRI with axial Fat Suppression Proton Density Weighted Image (FS-PDWI), sagittal fat suppression T2 Weighted Image (FS-T2WI), coronal T1Weighted Image (T1WI), FS-PDWI, cartilage-specific T1, T2 and T2* mapping sequences. Basing on MRI images, the shoulder cartilage was classified into grades 0 1, 2, 3 and 4 according to the International Cartilage Regeneration & Joint Preservation Society (ICRS). The grading of shoulder cartilage was based on MRI images with ICRS as reference, and did not involve arthroscopy or histology.The T1, T2 and T2* relaxation values in the superior, middle and inferior bands of shoulder articular cartilage were measured at all grades, and the differences in various indicators between groups were analyzed and compared using a single-factor ANOVA test. The correlation between T1, T2 and T2* relaxation values and MRI-based grading was analyzed by SPSS software. There were 46 shoulder joints with MRI-based grade 0 in healthy control group (n = 46), while 49 and 28 shoulder joints with grade 1-2 (mild degeneration subgroup) and grade 3-4 (severe degeneration subgroup) in patient group (n = 73), accounting for 63.6% and 36.4%, respectively. The T1, T2 and T2* relaxation values of the superior, middle and inferior bands of shoulder articular cartilage were significantly and positively correlated with the MRI-based grading (P < 0.01). MRI-basedgrading of shoulder cartilage was markedly associated with age (r = 0.766, P < 0.01). With the aggravation of cartilage degeneration, T1, T2 and T2* relaxation values showed an upward trend (all P < 0.01), and T1, T2 and T2* mapping could distinguish cartilage degeneration at all levels (all P < 0.01). The T1, T2 and T2* relaxation values were significantly different between normal group and mild degeneration subgroup, normal group and severe degeneration subgroup, mild degeneration subgroup and severe degeneration subgroup (all P < 0.05). Quantitative T1, T2 and T2* mapping can quantify the degree of shoulder cartilage degeneration. All these MRI mapping quantification techniques can be used as critical supplementary sequences to assess shoulder cartilage degeneration, among which T2 mapping has the highest value.

Reliability of Radiographic Imaging Characteristics for Osteochondritis Dissecans of the Capitellum

BACKGROUND

A primary challenge in the treatment of capitellar osteochondritis dissecans (OCD) is accurate imaging assessment. Radiographic classification consensus is not available in the current literature, and correlation of radiographs with lesion stability and resultant best treatment is lacking.

PURPOSE

To determine the inter- and intrarater reliability of the presence or absence and common radiographic characteristics of capitellar OCD lesions.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 3.

METHODS

Anteroposterior, lateral, and oblique radiographs for 29 cases were reviewed by 7 orthopaedic surgeons. Images were assessed for elbow anthropometry and morphology, OCD presence, lesion characteristics, the presence of progeny bone and progeny features, and radial head abnormalities. Intra- and interrater reliability was assessed using Fleiss and Cohen kappa for nominal variables and intraclass correlation coefficients (ICCs) for continuous variables.

RESULTS

Surgeons demonstrated substantial to excellent inter- and intrarater reliability when assessing elbow characteristics: anthropometric (interrater ICC, 0.94-0.99; intrarater ICC, 0.82-0.96) and morphologic (Fleiss, 0.61-0.76; Cohen, 0.68). When the OCD lesion was assessed, fair to moderate interrater agreement was found for classifying the absence or presence of a lesion (Fleiss, 0.28-0.46) and the location of the OCD (Fleiss, 0.24-0.52), poor agreement for assessing the contour of the lesion (Fleiss, 0.00-0.09), and excellent agreement for measuring the size of the lesion (ICC, 0.82-0.94). Poor to fair interrater agreement was found for radial head abnormalities (Fleiss, 0.00-0.27). Progeny bone visualization and fragmentation demonstrated moderate interrater agreement (Fleiss, 0.43-0.47) where displacement of the bone demonstrated poor interrater agreement (Fleiss, 0.11-0.16). Intrarater agreement for OCD lesion characteristics, progeny bone visualization, and progeny bone features was moderate to excellent.

CONCLUSION

Given only the fair to moderate agreement among raters for identifying OCD on radiographs, this imaging modality may not serve as a dependable screening tool in isolation. Additional imaging should be obtained if the clinical presentation suggests capitellar OCD and a definitive diagnosis is not possible with radiographs. However, clinicians can reliability measure the size of radiographically apparent OCD, suggesting that radiographs may serve as an appropriate imaging modality for follow-up care.

Preoperative Evaluation and Surgical Simulation for Osteochondritis Dissecans of the Elbow Using Three-Dimensional MRI-CT Image Fusion Images

We used our novel three-dimensional magnetic resonance imaging-computed tomography fusion images (3D MRI-CT fusion images; MCFIs) for detailed preoperative lesion evaluation and surgical simulation in osteochondritis dissecans (OCD) of the elbow. Herein, we introduce our procedure and report the findings of the assessment of its utility. We enrolled 16 men (mean age: 14.0 years) and performed preoperative MRI using 7 kg axial traction with a 3-Tesla imager and CT. Three-dimensional-MRI models of the humerus and articular cartilage and a 3D-CT model of the humerus were constructed. We created MCFIs using both models. We validated the findings obtained from the MCFIs and intraoperative findings using the following items: articular cartilage fissures and defects, articular surface deformities, vertical and horizontal lesion diameters, the International Cartilage Repair Society (ICRS) classification, and surgical procedures. The MCFIs accurately reproduced the lesions and correctly matched the ICRS classification in 93.5% of cases. Surgery was performed as simulated in all cases. Preoperatively measured lesion diameters exhibited no significant differences compared to the intraoperative measurements. MCFIs were useful in the evaluation of OCD lesions and detailed preoperative surgical simulation through accurate reproduction of 3D structural details of the lesions.

Radiographic evaluation of osteochondritis dissecans of the humeral capitellum: A systematic review

Background

The purpose of this study was to evaluate radiographic-based classification systems for osteochondritis dissecans (OCD) of the capitellum and determine their agreement with intraoperative findings.

Methods

Using PRISMA guidelines, we analyzed 44 studies utilizing a total of 19 classification systems.

Results

Magnetic resonance imaging (MRI)-based systems showed better predictive value of intraoperative staging, and the Itsubo and Kohyama classifications showed best predictive value for lesion stability.

Conclusions

No classification system effectively correlated with intraoperative findings. A combination of radiograph, MRI, and computed tomography will most accurately determine OCD lesion stability.

Level of evidence

IV, Systematic Review.

Radiographic and MRI Assessment of the Thrower's Elbow

PURPOSE OF REVIEW

Throwing athletes are vulnerable to elbow injuries, especially in the medial elbow, related to high stress and valgus load in both acute and chronic settings as a result of this complex biomechanical action. This current review details the relevant anatomy and imaging features of common elbow pathology identified with radiographs and MRI in throwing athletes.

RECENT FINDINGS

Although elbow pathology in throwing athletes is well documented, advances in imaging technology and technique, particularly with MRI, have allowed for more detailed and accurate imaging description and diagnosis. Pathology of thrower's elbow occurs in predictable patterns and can be reliably identified radiologically. Clinical history and physical examination should guide radiologic evaluation initially with radiographs and followed by an MRI optimized to the clinical question. Constellation of clinical, physical, and radiologic assessments should be used to guide management.

Magnetic Resonance Imaging in Osteochondritis Dissecans of the Humeral Capitellum: Preoperative Assessment of Lesion Size and Lateral Wall Integrity

PURPOSE

Magnetic resonance imaging (MRI) is a helpful tool in the evaluation of osteochondritis dissecans (OCD) of the humeral capitellum. The relationship between MRI appearance and clinically relevant intraoperative findings is incompletely understood. The goal of this study was to evaluate capitellar OCD lesions via preoperative MRI and to determine its accuracy in predicting lesion characteristics including lesion size and capitellar lateral wall integrity.

METHODS

Patients surgically treated for capitellar OCD between January 2010 and June 2018 were reviewed. Preoperative MRI images were assessed by a musculoskeletal radiologist with documentation of lesion size, location, violation of the lateral wall, and stage, in accordance with previously established criteria. These data were compared with intraoperative findings. Involvement of the lateral wall of the capitellum was defined using 2 methods: (1) subchondral edema or articular cartilage disruption in the lateral third of the capitellum (lateral third method) or (2) disruption of the proximal-distal subchondral line along the lateral border of the capitellum descending vertically before the subchondral bone turns horizontally to form the radiocapitellar articulation (capitellar lateral wall sign method). Diagnostic test characteristics were compared for both methods.

RESULTS

We reviewed the preoperative MRIs of 33 elbows with capitellar OCD and found no significant difference in mean lesion size between preoperative MRI (1.12 cm²) and intraoperative measurement (1.08 cm²). For detection of lateral wall integrity, preoperative MRI evaluation using the capitellar lateral wall sign method had an accuracy of 93%, sensitivity of 80%, specificity of 96%, positive predictive value of 80%, and negative predictive value of 96%.

CONCLUSIONS

Preoperative MRI is a valid predictor of lesion size. The capitellar lateral wall sign method is highly accurate in the identification of lateral wall involvement, which may influence preoperative planning.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

A novel three-dimensional MRI-CT image fusion technique for precise preoperative evaluation and treatment of capitellar osteochondritis dissecans

OBJECTIVES

We developed a novel method to create three-dimensional magnetic resonance imaging-CT (3D MRI-CT) fusion images for detailed lesion evaluation and surgical simulation in capitellar osteochondritis dissecans (COCD). This study aimed to clarify its usefulness.

METHODS

We enrolled 12 boys with COCD (mean age, 13.8 years) and preoperatively constructed 3D models of the humerus and articular cartilage from MR images obtained with a 3-T imager. For better visualization of the articular cartilage outline, we applied 7 kg of axial traction to the elbow during MRI. We also constructed a 3D model of the humerus from CT images. 3D MRI-CT fusion images were created using both models. The average distance difference between two corresponding points as per the 3D CT and 3D MRI models of the humerus was evaluated. Using the 3D MRI-CT fusion images, we measured longitudinal and transverse lesion diameters; evaluated articular cartilage fissures and defects, articular surface deformities, and the International Cartilage Repair Society (ICRS) classification; and validated the results using intraoperative findings.

RESULTS

The mean average distance difference was 0.75 mm. The 3D MRI-CT fusion images accurately reproduced lesion conditions in every case and correctly predicted the ICRS classification with 100% accuracy. Preoperatively measured longitudinal and transverse lesion diameters were not significantly different from intraoperative measurements (p = 0.79, 0.32 respectively).

CONCLUSION

3D MRI-CT fusion images provide a detailed evaluation of COCD lesion severity by presenting the exact positional relationship between the articular cartilage and subchondral bone.

KEY POINTS

• We developed a novel method to create three-dimensional magnetic resonance imaging-computed tomography (3D MRI-CT) fusion images for the evaluation of capitellar osteochondritis dissecans. • 3D MRI-CT fusion images enabled the accurate prediction of lesions and provided a detailed evaluation of lesion severity by presenting the exact positional relationship between the articular cartilage and subchondral bone.

Effect of elbow MRI with axial traction on articular cartilage visibility-a feasibility study

OBJECTIVE

Accurate evaluation of the articular cartilage of the elbow using MRI is sometimes challenging because of its anatomical complexity and relatively small size. Moreover, the articular cartilage of the humerus is in close contact with the opposing cartilage surfaces. Magnetic resonance arthrography with traction was reported to resolve this issue; however, less invasive methods are desirable. This study aimed to assess the effect of MRI with axial traction (without arthrography) on joint space widening and cartilage outline visibility of the elbow.

MATERIALS AND METHODS

We enrolled 10 volunteers (female = 1; mean age, 36.7 ± 8.6; range 28-56) and performed MRI with and without axial traction on the elbow. Joint space widths were measured, and the humeral articular cartilage outline visibility was evaluated at the radiocapitellar joint and lateral one-third and medial one-third of the ulnohumeral joints. Measurements were compared using the Wilcoxon signed-rank test. Significance was set at p < 0.05. Volunteers scored pain and discomfort during MRI with traction using the visual analog scale in a questionnaire format.

RESULTS

Traction significantly increased joint space width at the radiocapitellar joint. Humeral articular cartilage outline visibility also significantly improved at the radiocapitellar joint. Pain and discomfort scores during traction MRI were low.

CONCLUSION

MRI of the elbow with traction widens joint space and enables better articular cartilage visibility at the radiocapitellar joint. Anatomical features of the elbow might have affected these results. Therefore, it would be safe and useful for evaluating elbow injuries involving articular cartilage lesions.