Sonographic assessment of osteochondritis dissecans of the humeral capitellum

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.

Deep learning-based osteochondritis dissecans detection in ultrasound images with humeral capitellum localization

PURPOSE

Osteochondritis dissecans (OCD) of the humeral capitellum is a common cause of elbow disorders, particularly among young throwing athletes. Conservative treatment is the preferred treatment for managing OCD, and early intervention significantly influences the possibility of complete disease resolution. The purpose of this study is to develop a deep learning-based classification model in ultrasound images for computer-aided diagnosis.

METHODS

This paper proposes a deep learning-based OCD classification method in ultrasound images. The proposed method first detects the humeral capitellum detection using YOLO and then estimates the OCD probability of the detected region probability using VGG16. We hypothesis that the performance will be improved by eliminating unnecessary regions. To validate the performance of the proposed method, it was applied to 158 subjects (OCD: 67, Normal: 91) using five-fold-cross-validation.

RESULTS

The study demonstrated that the humeral capitellum detection achieved a mean average precision (mAP) of over 0.95, while OCD probability estimation achieved an average accuracy of 0.890, precision of 0.888, recall of 0.927, F1 score of 0.894, and an area under the curve (AUC) of 0.962. On the other hand, when the classification model was constructed for the entire image, accuracy, precision, recall, F1 score, and AUC were 0.806, 0.806, 0.932, 0.843, and 0.928, respectively. The findings suggest the high-performance potential of the proposed model for OCD classification in ultrasonic images.

CONCLUSION

This paper introduces a deep learning-based OCD classification method. The experimental results emphasize the effectiveness of focusing on the humeral capitellum for OCD classification in ultrasound images. Future work should involve evaluating the effectiveness of employing the proposed method by physicians during medical check-ups for OCD.

Improving Visualization of Osteochondritis Dissecans Using Delay-Multiply-and-Sum Reconstruction

OBJECTIVE

Osteochondritis dissecans (OCD) of the capitellum is a joint defect that is common among adolescent athletes. It is important to diagnose OCD as early as possible, because early-stage OCD lesions have a high rate of spontaneous healing with rest. Medical ultrasound could potentially be used as a screening tool for OCD but is limited by the use of delay-and-sum (DAS) reconstruction. In this study, we tested conventional delay-multiply-and-sum (DMAS) and novel low-pass DMAS reconstruction algorithms for better visualization of OCD lesions.

METHODS

We created phantom and cadaveric OCD models that simulated a range of OCD lesion severities and stabilities. We also imaged an in vivo case of OCD in a patient study. In the reconstructed images, several profiles were taken to measure OCD lesion contrast, cartilage contrast, crack thickness error and bone interface clarity.

RESULTS

In the phantom and cadaveric OCD models, we found that histogram-matched conventional DMAS reconstruction improved lesion contrast by up to 16%, cartilage contrast by 26% and bone interface clarity by 15% on average compared with DAS reconstruction. Histogram-matched low-pass DMAS reconstruction improved lesion contrast by up to 22%, cartilage contrast by 45%, and bone interface clarity by 29% on average compared with DAS reconstruction. In the in vivo case of OCD, we found that histogram-matched conventional and low-pass DMAS reconstruction improved lesion contrast by 22% and 26%, respectively.

CONCLUSION

The application of DMAS reconstruction improved the ability of medical ultrasound to detect OCD lesions of the capitellum when compared with DAS reconstruction.

Advantages of CT Versus MRI for Preoperative Assessment of Osteochondritis Dissecans of the Capitellum

BACKGROUND

Magnetic resonance imaging (MRI) is considered to be the gold standard for imaging of osteochondritis dissecans (OCD).

PURPOSE/HYPOTHESIS

The purpose was to determine the additional value of a preoperative computed tomography (CT) scan in adolescent patients with capitellar OCD of the elbow. Consistent with the fact that OCD is a lesion involving the subchondral bone, the hypothesis was that CT would be superior to MRI for imaging OCD of the capitellum.

STUDY DESIGN

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

METHODS

All patients being treated surgically for an OCD of the capitellum between 2006 and 2016 at one institution were reviewed for preoperative imaging. A total of 28 patients met the inclusion criteria. Corresponding MRI and CT scans were compared retrospectively. Multiple parameters were recorded, with special emphasis on OCD lesion size, fragmentation, and tilt as well as joint surface integrity, loose bodies, and osteophytes.

RESULTS

The OCD lesions were best seen on CT scans, whereas MRI T1-weighted images overestimated and T2-weighted images underestimated the size of defects. A subchondral fracture nonunion was found on CT scans in 18 patients, whereas this was seen on MRI T1-weighted images in only 2 patients (P < .001) and MRI T2-weighted images in 4 patients (P < .001). Fragmentation of the OCD fragment was found on CT scans in 17 patients but on MRI scans in only 9 patients (P = .05). Osteophytes as a sign of secondary degenerative changes were seen on CT scans in 24 patients and were seen on MRI scans in 15 patients (P = .02). Altogether, only 51 of 89 secondary changes including loose bodies, effects on the radial head and ulnohumeral joint, and osteophytes that were seen on CT scans were also seen on MRI scans (P = .002).

CONCLUSION

OCD fragmentation and secondary changes were more often diagnosed on CT. These factors indicate OCD instability or advanced OCD stages, which are indications for surgery. In an adolescent who is considered at risk for OCD (baseball, gymnastics, weightlifting, tennis) and who has lateral elbow joint pain with axial or valgus load bearing, CT is our imaging modality of choice for diagnosing and staging OCD of the capitellum.

Conservative treatment for stable osteochondritis dissecans of the elbow before epiphyseal closure: effectiveness of elbow immobilization for healing

BACKGROUND AND HYPOTHESIS

Stable lesions of osteochondritis dissecans (OCD) of the capitellum have been treated with activity restriction (AR), and the complete healing requires 1 or 2 years. Little is known about the effectiveness of elbow immobilization. We hypothesized that elbow immobilization would have positive effects on healing of stable OCD.

METHODS

The study subjects were 43 patients (mean age: 12.2 years) with 43 stable OCD lesions of the prematured elbow (mean skeletal age score: 17.1 points of 0-27 points system). The subjects were divided into 3 groups: group A, AR without elbow immobilization, 22 cases; group B, splint (mean: 8.8 weeks) followed by AR, 9 cases; and group C, cast (mean: 3.7 weeks) followed by splint (mean: 7.3 weeks) and AR, 12 cases. The mean nonoperative observation period was 17.5 months (minimum three months). On anteroposterior radiographs of the elbow at 45 degrees of flexion, 5 observers independently assessed the healing of the capitellum, and the interobserver and intraobserver reliabilities were examined. The differences in outcomes among 3 groups were also examined.

RESULTS

The interobserver and intraobserver reliabilities of the radiographic assessment were almost perfect (Cohen kappa value: 0.82 and 0.91, respectively). There were no significant differences in age, sports played, or stage of the lesion before the treatment. The proportion of patients returning to sports and the mean period required were 77% and 8.2 months in group A, 78% and 5.7 months in group B, and 83% and 4.4 months in group C, respectively. The proportion of patients showing ossification in the central aspect of the capitellum and the mean period required were 67% and 8.2 months in group A, 63% and 4.9 months in group B, and 91% and 1.9 months in group C, respectively. The proportion of patients showing complete healing and the mean period required were 41% and 16.4 months in group A, 67% and 7.0 months in group B, and 92% and 5.5 months in group C, respectively. Compared to group A, group C showed a significantly earlier return to sports (P = .034), a significantly shorter period required for ossification (P < .001), and significantly higher proportion of patients with complete healing (P = .012) within a significantly shorter period (P = .009).

CONCLUSION

Elbow immobilization had positive effects on healing and enabled both an early return to sports and complete healing. Cast immobilization is recommended as a first choice of nonoperative treatment for stable OCD lesions of the elbow before epiphyseal closure.

Staging of osteochondritis dissecans of the elbow based on pathologic progression in the partially detached articular fragment

BACKGROUND

Osteochondritis dissecans (OCD) is considered to show the following stages of pathologic progression: IA, nearly normal-cartilaginous; IB, deteriorated-cartilaginous; IIA, cartilage-ossifying; and IIB, cartilage-osteonecrotic. However, the validity of this pathologic staging for OCD has yet to be confirmed in a large number of cases.

PURPOSE

The aim of the present study was to confirm the clinical validity of the proposed pathologic staging of OCD.

METHODS

The subjects were 74 patients (mean age, 14.2 years; mean skeletal age score, 25.6 points) with capitellar OCD. Partially detached articular fragments were surgically removed and were examined histologically. The articular fragments were independently assessed by 5 observers, and the reliability of assessment was examined. The correlation between the pathologic stages and the clinical data was analyzed.

RESULTS

The reliability of the assessment among 5 observers was almost perfect. OCD stages of IA, IB, IIA, and IIB were evident in 8, 36, 10, and 20 patients, respectively. OCD-I (cartilaginous) and OCD-II (osteochondral) corresponded significantly to radiographic stage I (radiolucency) and stage II (delayed ossification), respectively. The pathologic OCD stages were significantly correlated with the clinical data, including the period from symptom onset to surgery, patient age, and the skeletal age score (P < .01).

CONCLUSION

Our results confirmed that the proposed pathologic staging of OCD corresponds to the observed clinical progression of OCD, thus validating the staging system. Our findings revealed that OCD begins with separation beneath the epiphyseal cartilage, which is programmed to be replaced with bone. When a stage IA articular fragment has remained partially detached for a prolonged period, the epiphyseal cartilage may be deteriorated and become degenerated, and subsequent ossification may not occur, as is evident in OCD-IB. In contrast, stage IA with a vascular supply through the fibrocartilaginous connection can progress to stage IIA. During the prolonged period in which the osteochondral articular fragment remains ununited, microtrauma can cause to disturb the blood supply to the bony fragment, resulting in osteonecrosis (stage IIB).

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.

Risk factor for elbow symptom manifestation in young baseball players with asymptomatic medial elbow abnormalities: a prospective cohort study

Asymptomatic elbow abnormalities are relatively common in young baseball players, but the factors responsible are unclear. To prospectively identify risk factors related to symptom manifestation in asymptomatic elbow abnormalities, we recruited 573 baseball players (age: 7-14 years) at a pre-participation medical/physical examination in the preseason who were right-handed and had asymptomatic medial elbow abnormalities on ultrasound (US). Baseline preseason and postseason participant characteristics were assessed. A "symptomatic" elbow was defined as an elbow with medial elbow joint problems that prevented ball throwing for ≥ 8 days. After exclusions, 82 players were enrolled, of whom 22 (26.8%) developed a symptomatic elbow. In univariate analyses, the external and internal rotation strengths of the dominant shoulder were significantly greater in the symptomatic group than in the asymptomatic group (P = 0.021). Multivariate logistic regression analysis showed that the internal rotation strength of the dominant shoulder was a significant independent risk factor (odds ratio = 1.091, P = 0.027) for developing a symptomatic elbow. In young asymptomatic baseball players with abnormalities in the medial elbow region of the dominant arm on US, stronger preseason internal rotation strength of the dominant shoulder was a significant independent risk factor for the development of a "symptomatic" elbow.

Osteochondritis Dissecans: Current Understanding of Epidemiology, Etiology, Management, and Outcomes

➤

Osteochondritis dissecans occurs most frequently in the active pediatric and young adult populations, commonly affecting the knee, elbow, or ankle, and may lead to premature osteoarthritis.

➤

While generally considered an idiopathic phenomenon, various etiopathogenetic theories are being investigated, including local ischemia, aberrant endochondral ossification of the secondary subarticular physis, repetitive microtrauma, and genetic predisposition.

➤

Diagnosis is based on the history, physical examination, radiography, and advanced imaging, with elbow ultrasonography and novel magnetic resonance imaging protocols potentially enabling early detection and in-depth staging.

➤

Treatment largely depends on skeletal maturity and lesion stability, defined by the presence or absence of articular cartilage fracture and subchondral bone separation, as determined by imaging and arthroscopy, and is typically nonoperative for stable lesions in skeletally immature patients and operative for those who have had failure of conservative management or have unstable lesions.

➤

Clinical practice guidelines have been limited by a paucity of high-level evidence, but a multicenter effort is ongoing to develop accurate and reliable classification systems and multimodal decision-making algorithms with prognostic value.

Asymptomatic Medial Elbow Ultrasound Abnormality in Youth Baseball Players Is an Independent Risk Factor for Elbow Injury: A Prospective Cohort Study

Background

Youth baseball players who experience elbow pain during the season frequently exhibit radiographic elbow abnormalities. However, it is unknown whether asymptomatic elbow abnormalities are risk factors for in-season elbow injuries.

Purpose

To determine whether the preseason presence of asymptomatic medial epicondyle apophysitis is a risk factor for in-season elbow injuries in youth baseball players.

Study Design

Cohort study; Level of evidence, 2.

Methods

Youth baseball players (N = 210; age range, 7-12 years) with no pain or history of injury in their throwing arms underwent preseason evaluations that included shoulder and elbow range of motion measurements, shoulder muscle strength testing, and ultrasound elbow scans with a multifrequency 13-MHz linear array transducer. Over 1 year of play, the players and their parents maintained daily elbow pain diaries. Elbow injuries were defined as medial elbow symptoms that prevented ball throwing for ≥8 days.

Results

The preseason ultrasound evaluation revealed medial epicondyle apophysitis in 59 players. In the year following, elbow injuries occurred in 17 (28.8%) players with preseason medial epicondyle apophysitis and 18 (11.9%) players without apophysitis. Independent predictors of elbow injuries were preseason medial epicondyle apophysitis (odds ratio [OR], 2.488; 95% confidence interval [CI], 1.152-5.376; P = .02) and deficits of abduction (ABD) and external rotation of the dominant shoulder (OR, 0.963; 95% CI, 0.936-0.992; P = .012).

Conclusion

Asymptomatic medial epicondyle apophysitis and ABD and external rotation deficits in the dominant shoulder were risk factors for elbow injuries in 7- to 12-year-old youth baseball players. These findings may aid in the design of programs to prevent elbow injuries in this population.

Progression of Epiphyseal Cartilage and Bone Pathology in Surgically Treated Cases of Osteochondritis Dissecans of the Elbow

BACKGROUND

Although a variety of pathologic conditions associated with osteochondritis dissecans (OCD) have been reported, the pathological progression has remained unclear.

HYPOTHESIS

Separation of the immature epiphyseal cartilage is an early event in OCD, and osteonecrosis in the articular fragment is a late event.

STUDY DESIGN

Case Series; Level of evidence, 4.

METHODS

The participants were 26 boys (mean age, 13.8 years; mean skeletal age score for the elbow, 24.6 points) with capitellar OCD who underwent osteochondral autograft transplantation. A total of 28 cylindrical osteochondral plugs, including the articular fragment, an intermediate layer, and proximal epiphyseal bone, were harvested from the central area of the capitellum and were examined histologically. The articular fragments of OCD were independently assessed by 5 observers and divided into 4 pathological variations: IA, nearly normal-cartilaginous; IB, deteriorated-cartilaginous; IIA, cartilage-ossifying; and IIB, cartilage-osteonecrotic. The reliability of assessment and the correlation of the pathological variations with the clinical data were examined.

RESULTS

The reliability of the assessment among 5 observers was almost perfect (Cohen kappa value = 0.91). OCD variations of IA, IB, IIA, and IIB were evident in 5, 10, 5, and 6 patients, respectively. OCD-I (cartilaginous) and OCD-II (osteochondral) corresponded significantly to radiographic stage I (radiolucency or slight calcification with open physis) and stage II (delayed ossification or bony fragment), respectively (Cohen kappa value = 0.79; percentage agreement = 81%). The pathological OCD variations were significantly correlated with the clinical data, including the period from symptom onset to surgery, patient age, and the skeletal age score (P < .01, in each).

CONCLUSION

The present study has revealed that the pathological variations correspond to the progression of OCD, thus proving our hypothesis. OCD-IA was shown to be an early lesion caused by separation of the immature epiphyseal cartilage. OCD-IB appeared to result from ossification arrest over a prolonged period from the onset of OCD-IA, whereas OCD-IIA showed delayed ossification in the epiphyseal cartilage where vascularization from the surrounding bone had been established. Osteonecrosis in OCD-IIB was shown to be a late pathological event caused by disruption of the vascular supply to OCD-IIA.

Osteochondritis Dissecans of the Capitellum :Review of the Literature

Osteochondritis dissecans (OCD) of the capitellum is a leading cause of elbow disability in adolescent baseball players. Previous studies have not found an association of player position with capitellar OCD. Elbow pain and a longer playing history might be related to progression of capitellar OCD but do not in themselves increase the risk of development of the condition. The cause of capitellar OCD is likely to include a combination of repetitive microtrauma and internal factors, such as ischemia and genetic predisposition. A combination of radiography, computed tomography, magnetic resonance imaging, and ultrasonography have aided our understanding of the pathology of capitellar OCD. Screening using ultrasonography enables early detection and provides an opportunity for successful conservative treatment. Treatment has conventionally included both operative and nonoperative measures based on the stage and size of the lesion, skeletal maturity, subjective symptoms, and structural integrity of the cartilage. Early-stage lesions respond better to nonoperative treatment than those in more advanced stages. Operative indications include persistent symptoms despite nonoperative treatment, symptomatic loose bodies, and displacement or detachment of fragments. J. Med. Invest. 67 : 217-221, August, 2020.

Cumulative Incidence of Osteochondritis Dissecans of the Capitellum in Preadolescent Baseball Players

PURPOSE

To quantify the 1-year cumulative incidence of capitellar osteochondritis dissecans (OCD) in preadolescent baseball players and identify the risk factors associated with this condition.

METHODS

In total, 1,275 school-aged baseball players (aged 6-11 years) without an established diagnosis of capitellar OCD were enrolled in this longitudinal, observational study. One year later, all players underwent ultrasonographic examination of the throwing elbow on the playing field. Elbows with abnormal ultrasonographic findings at this time then underwent radiographic examination. Data for the groups with and without capitellar OCD were analyzed using multivariate logistic regression models.

RESULTS

The 1-year cumulative incidence of capitellar OCD was 1.8% (95% confidence interval, 1.1%-2.7%). On multivariate analysis, players aged 10 to 11 years were 3.96 times more likely to have capitellar OCD (95% confidence interval, 1.10-18.97) than those aged 6 to 9 years; however, starting baseball at an earlier age, number of years played, training hours per week, player position, and history of elbow pain were not significantly associated with capitellar OCD. Only 34.8% of players with capitellar OCD reported elbow pain.

CONCLUSIONS

The risk of OCD of the capitellum developing within a 1-year period in preadolescent baseball players was 1.8%. Players aged 10 to 11 years had a significantly greater risk of capitellar OCD development than those aged 6 to 9 years.

LEVEL OF EVIDENCE

Level III, local nonrandom sample cohort.

Demographics and Epidemiology of Osteochondritis Dissecans of the Elbow Among Children and Adolescents

Background

Osteochondritis dissecans (OCD) of the elbow is a disorder of subchondral bone and articular cartilage, of which the incidence among children is not clearly known.

Purpose

To assess the demographics and epidemiology of OCD of the elbow among children.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

A retrospective chart review of an integrated health system for the years 2007 through 2011 was performed for patients with elbow OCD aged 2 to 19 years. Lesion location, laterality, and all patient demographics were recorded. OCD incidence was determined for the group as a whole as well as by sex and age group (2-5, 6-11, 12-19 years). Patient differences based on age, sex, and ethnicity were analyzed, and multivariable logistic regression models were used to assess the risk of elbow OCD by group.

Results

A total of 37 patients with 40 OCD lesions fit the inclusion criteria. No lesion was found among 2- to 5-year-olds. A majority of lesions (n = 39, 97.5%) were in the capitellum, and 1 (2.5%) was in the trochlea. Twenty-five patients (67.6%) had right-sided lesions; 9 (24.3%), left-sided; and 3 (8.1%), bilateral. The incidence of elbow OCD for patients aged 6 to 19 years was 2.2 per 100,000 overall and 3.8 and 0.6 per 100,000 for males and females, respectively. The majority of OCD cases were seen in those aged 12 to 19 years, with an incidence of 3.4 per 100,000 versus 0.38 among 6- to 11-year-olds. Multivariable logistic regression analysis revealed a 21.7-times increased odds ratio of elbow OCD among patients aged 12 to 19 years versus 6 to 11 years, and males had a 6.8-times greater odds ratio of elbow OCD than females (P < .0001 for both). Based on race and ethnicity, non-Hispanic whites had the highest incidence of elbow OCD as compared with all other ethnic groups.

Conclusion

In this population-based cohort study of pediatric elbow OCD, males had almost 7 times the risk of elbow OCD as compared with females, and 12- to 19-year-olds had nearly 22 times the risk of elbow OCD versus 6- to 11-year-olds. In keeping with many prior studies, the majority of patients had right-sided lesions.

Effectiveness of ultrasonography screening and risk factor analysis of capitellar osteochondritis dissecans in adolescent baseball players

BACKGROUND

Capitellar osteochondritis dissecans (COCD) is a common elbow injury in young baseball athletes. It may be asymptomatic at the early stage and may progress if left untreated. This study investigated the effectiveness of ultrasonography (US) screening for COCD in adolescent baseball players and identified risk factors of COCD.

METHODS

A cross-sectional analysis study was conducted among baseball athletes aged 12 to 18 years. US screening of the throwing elbow was performed in all participants, and additional magnetic resonance imaging (MRI) was arranged for those with abnormal screening results. The prevalence of COCD was calculated according to MRI results. The US findings were compared with MRI findings. Data for characteristics, joint range of motion, and quality of pain were collected and analyzed using a logistic regression model to identify the risk factors of COCD.

RESULTS

A total of 299 adolescent baseball players were screened, and 17 were found to have COCD according to US findings. MRI was performed in 15 of these 17 players, and the MRI findings further confirmed COCD in 10 players (66.7%). The presence of elbow pain while at rest, body height, and age at introduction to baseball were predictors of COCD.

CONCLUSIONS

Although the effectiveness of diagnosing stage 1 COCD is satisfactory, US is a helpful tool for detecting stage 2 and higher-stage COCD. Elbow resting pain, lower body height, and introduction to baseball at a younger age are risk factors for COCD.

Elasticity of the pronator teres muscle in youth baseball players with elbow injuries: evaluation using ultrasound strain elastography

BACKGROUND

Although the pronator teres muscle, a major dynamic stabilizer of elbow valgus stress during throwing, frequently presents stiffness, its relationship with elbow injuries in youth baseball players is unknown. This study investigated the relationship between the elasticity of the pronator teres muscle and elbow injuries in youth baseball players.

METHODS

The strain ratio (SR) of 15 individuals with osteochondritis dissecans of the humeral capitellum (OCD group), 67 individuals with medial epicondylar fragmentation (medial injury group), and 115 healthy individuals (control group) was measured as the index of the elasticity of the pronator teres muscle using ultrasound strain elastography. In addition, the forearm and glenohumeral joint rotation range of motion was measured.

RESULTS

The SR of the throwing arm was significantly higher in the OCD and medial injury groups than in the control group (both P <.001). In the OCD group, the SR was significantly higher in the throwing arm than in the nonthrowing arm (P <.001), whereas in the medial injury group, there was no significant difference between both arms. The glenohumeral joint external rotation range of motion of the throwing arm was moderately negatively correlated with the SR (r = -0.478, P <.001).

CONCLUSIONS

Stiffness of the pronator teres muscle was exhibited only in the throwing arm of individuals with OCD and in both arms in individuals with medial elbow injury. These findings may contribute to an accurate evaluation and prevention of elbow injuries in youth baseball players.

Comparison of sonography and MRI in the evaluation of stability of capitellar osteochondritis dissecans

PURPOSE

To compare the diagnostic accuracies of ultrasonography (US) and magnetic resonance imaging (MRI) with intraoperative capitellar osteochondritis dissecans (COCD) fragment stability findings.

METHODS

Patients whose International Cartilage Repair Society (ICRS) osteochondritis dissecans (OCD) classifications were I/II (stable) or III (unstable) were included. Patients underwent preoperative US and MRI. On US, lesions were evaluated as unstable when irregular contours of the chondral surface were observed. On MRI, lesions were evaluated as unstable when articular bone irregularity, a T2 high signal intensity interface, or a high signal intensity line through the articular cartilage was observed. Using the surgical assessment as the gold standard, accuracies of fragment stability diagnoses were calculated for US and MRI.

RESULTS

Thirty-four patients with OCD classifications of I/II (stable) or III (unstable) were included. Twenty-four patients (stable: 12, unstable: 12) underwent preoperative US; 22 (stable: 11, unstable: 11) underwent preoperative MRI. Preoperative US and MRI stability assessments correctly matched intraoperative fragment findings in 23 of 24 patients and 16 of 22 patients, respectively. US criteria in this study achieved superior accuracy compared with MRI criteria (96% vs. 73%; P < .05).

CONCLUSION

US was a useful tool for evaluating fragment instability in COCD.

Diagnosis and treatment of osteochondritis dissecans of the humeral capitellum

Osteochondritis dissecans (OCD) of the humeral capitellum is a critical elbow injury in adolescent overhead throwing athletes. However, its etiology remains unknown. Medical examinations using ultrasonography found that the prevalence of capitellar OCD among adolescent baseball players was approximately from 1% to 3%. A plain anteroposterior radiograph with the elbow in 45° of flexion is essential for the diagnosis of an OCD lesion. The stability of OCD lesions is evaluated on plain radiographs, computed tomography, and magnetic resonance imaging (MRI). Imaging features of the unstable lesions are an epiphyseal closure of the capitellum or a lateral epicondyle, a displaced fragment, or irregular contours of the articular surface and a high signal interface on T2-weighted MRI. A stable lesion has the potential to be healed with conservative treatment. By contrast, surgical treatment should be considered if there is no radiographic improvement within 3 months. In addition, surgery should be performed for the lesions that cause pain during daily activities, have a locking phenomenon, or which are assessed by imaging as obviously unstable. Arthroscopic debridement/loose body removal can be performed for small lesions (≤12 mm in diameter). For large lesions (>12 mm), preservation and/or reconstruction of the articular surface should be selected, such as bone-peg fixation of the lateral part of the fragment and osteochondral autograft transplantation (OAT) from the knee. In the future directions, there is no comparative study of OAT from the knee and rib. In addition, little is known about its long-term outcome, or resulting osteoarthritis. A recent meta-analysis showed that grafts harvested from the knee may lead to donor site morbidity (7.8%). Thus, a novel cartilage tissue engineering approach is anticipated.

Grade I Osteochondritis Dissecans in a Young Professional Athlete

BACKGROUND

Osteochondritis dissecans (OCD) is a disorder primarily affecting subchondral bone, with secondary effects on the overlying articular cartilage. Knee joint (75%) and radiocapitellar joint (6%) are the most common sites for OCD lesions. The presence of an open growth plate differentiates juvenile osteochondritis dissecans from adult form of osteochondritis. Early diagnosis and treatment produce best long term results. The objective of this study is to determine the best mode of management of a Grade I osteochondritis lesion in a young athlete.

MATERIALS AND METHODS

A PubMed search was made using the keywords "OCD" and "athlete". Articles that were based on participants between the ages of 6-24 years (children, adolescent and young adult) and early stages of OCD were included in this study. A total of 25 articles were thus included for the review.

RESULTS

The healing potential is based on the age of the patient, status of physis, and stage of the lesion. Most authors have observed good to excellent results of drilling of early OCD in skeletally mature patients. Similarly, most authors also reported equally successful outcomes of nonoperative treatment for early OCD in skeletally immature patients.

CONCLUSIONS

We recommend initial nonoperative line of management in patients with open physis. In case of progression of the lesion or failure of conservative treatment a reparative, restorative or palliative surgical intervention can be done. For Stage I OCD lesions in patients with closed physis, we advocate reparative surgery either by means of retro- or trans-articular drilling.

Two-year follow-up study of subchondral surface irregularities of the capitellum on ultrasonography in baseball players under the age of 10 years

OBJECTIVE

To determine whether subchondral surface irregularities of the capitellum on ultrasonography in baseball players under the age of 10 years are indicative of early osteochondritis dissecans (OCD) of the capitellum.

MATERIALS AND METHODS

A total of 321 players aged 6-9 years underwent ultrasonographic examination, and the findings for the subchondral bone of the capitellum on the throwing side were graded as 0, 1a, 1b, 2, or 3. Subjects classified as grade 1a or 1b showed irregularities of the subchondral bone surface and were investigated radiographically for OCD. All players continued to throw and were re-examined by ultrasonography after 1 and 2 years.

RESULTS

At the first examination, 11/321 (3.4%) had irregularities at the subchondral surface of the capitellum [grade 1a in 7/321 (2.2%); grade 1b in 4/321 (1.2%)]. The seven players with grade 1a showed no evidence of OCD or Panner's disease on radiography and were reclassified as grade 0 at the 2-year follow-up. All four players with grade 1b were reclassified as grade 0 at follow-up 1 and 2 years later.

CONCLUSION

Subchondral bone surface irregularities of the capitellum on ultrasonography in children under the age of 10 years may not be indicative of disease, but rather represent variation of ossification during normal development.

Age-Specific Prevalence and Clinical Characteristics of Humeral Medial Epicondyle Apophysitis and Osteochondritis Dissecans: Ultrasonographic Assessment of 4249 Players

Background:

Traction apophysitis of medial epicondyle (MEC) lesions and osteochondritis dissecans (OCD) of the capitellum are common elbow injuries in adolescent baseball players. However, the age-specific prevalence of these pathologies and their influence on elbow pain remain unknown.

Purpose:

To investigate the age-specific prevalence of each MEC lesion and capitellar OCD and to identify the incidence of elbow pain in each condition.

Study Design:

Descriptive epidemiology study.

Methods:

Study participants consisted of 4249 baseball players aged 6 to 17 years. A questionnaire was used to assess history of elbow pain, and morphological changes of the elbow joint were assessed using ultrasonography.

Results:

Regarding MEC lesions, fragmented (FG) and irregular (IR) lesions both reached their greatest respective prevalence at 11 to 12 years of age. After 14 years of age, IR decreased sharply, whereas FG was maintained at approximately 10%. Hypertrophic (HT) lesions increased sharply, reaching over 50% at 16 years of age, while there was a decrease in IR and FG lesions in the same age group. The prevalence of capitellar OCD remained the same (approximately 2%) throughout all ages except for in players aged 7 to 8 years (>7%). Players with MEC lesions had significantly greater prevalence of a history of elbow pain compared with those without (68.0% vs 39.1%) and were at a significantly greater risk for FG lesions (odds ratio [OR], 4.04; 95% CI, 3.16-5.22) compared with IR (OR, 3.22; 95% CI, 2.44-4.27) and HT lesions (OR, 2.03; 95% CI, 1.75-2.36). Players with capitellar OCD also had a significantly greater risk of a history of elbow pain (OR, 2.34; 95% CI, 1.40-4.11).

Conclusion:

Controlling the amount of practice and its intensity according to the condition of each player in the preadolescent and adolescent periods may be important in accelerating bony healing and decreasing preventable elbow pain in adulthood.

Osteochondritis Dissecans of the Humeral Capitellum in Young Athletes: Comparison Between Baseball Players and Gymnasts

Background:

Osteochondritis dissecans (OCD) lesions are often observed in the humeral capitellum both in young baseball players and gymnasts. It is generally believed that capitellar OCD in baseball players can be seen on an anteroposterior (AP) radiograph with the elbow in 45° of flexion. However, the mechanism of injury seems to be different in baseball players and gymnasts. Repetitive valgus overload with the elbow in flexion is believed to be the cause of capitellar OCD lesions in baseball players, whereas weightbearing with the elbow in extension may be the cause of OCD in gymnasts.

Purpose:

To determine the difference in capitellar OCD location between baseball players and gymnasts and to propose the optimal AP radiographic angle of the elbow for visualization of early-stage OCD lesions in adolescent gymnasts.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

Subjects consisted of 95 baseball players (95 elbows) and 21 gymnasts (24 elbows) with a mean age of 13.7 years (range, 11-18 years). To localize the lesion, inclination of the affected area in the humeral capitellum against the humeral axis was investigated using sagittal computed tomography images of the elbow. The inclination angle was defined as the angle between the long axis of the humerus and the line perpendicular to a line that connected the anterior and posterior margin of the lesion. The inclination angle in each group was compared and statistically analyzed.

Results:

The mean inclination angle was 57.6° ± 10.7° in baseball players and 28.0° ± 10.7° in gymnasts. Capitellar OCD lesions were located more anterior in baseball players when compared with gymnasts (P < .01).

Conclusion:

Due to differences in applied stress, capitellar OCD lesions in baseball players were located more anteriorly compared with those seen in gymnasts. Therefore, although AP radiographs with the elbow in 45° of flexion are optimal for detecting OCD lesions in baseball players, radiographs with less elbow flexion or full extension are more useful in gymnasts, especially in early-stage OCD.

A clinical and ultrasonographic study of risk factors for elbow injury in young baseball players

PURPOSE

To determine the risk factors for elbow injury and its association with glenohumeral internal rotation deficit among young baseball players.

METHODS

229 baseball players aged 9 to 14 (mean, 11) years completed a self-administered questionnaire with items related to years of playing baseball, hours of training per weekday, days of training per week, and past and present experience of elbow pain. Two orthopaedic surgeons measured the range of motion of both shoulders and elbows. Another 2 orthopaedic surgeons performed ultrasonography to detect any elbow abnormality such as fragmentation of the medial epicondylar apophysis and osteochondritis dissecans of the capitellum. Using univariate and multivariable analyses, participants with or without elbow abnormality were compared to determine the risk factors for elbow abnormality.

RESULTS

Elbow abnormality was detected in 100 of the participants and comprised osteochondritis dissecans of the capitellum (n=18) and fragmentation of the medial epicondylar apophysis (n=82). Elbow abnormality was associated with being a pitcher, past and present experience of elbow pain, loss of elbow extension, and the side-to-side internal rotation difference. The 100 participants with elbow abnormality were stratified into symptomatic (n=57) or asymptomatic (n=43) of elbow pain. Those with elbow abnormality and elbow pain was associated with being a pitcher.

CONCLUSION

Being a pitcher was a risk factor for both elbow abnormality and elbow pain. Nonetheless, 43% of baseball players with elbow abnormality were asymptomatic. The use of ultrasonography was effective in detecting elbow abnormality and enabling early treatment.

Osteochondritis dissecans of the capitellum in adolescents

Osteochondritis dissecans (OCD) is a disorder of articular cartilage and subchondral bone. In the elbow, an OCD is localized most commonly at the humeral capitellum. Teenagers engaged in sports that involve repetitive stress on the elbow are at risk. A high index of suspicion is warranted to prevent delay in the diagnosis. Plain radiographs may disclose the lesion but computed tomography and magnetic resonance imaging are more accurate in the detection of OCD. To determine the best treatment option it is important to differentiate between stable and unstable OCD lesions. Stable lesions can be initially treated nonoperatively with elbow rest or activity modification and physical therapy. Unstable lesions and stable lesions not responding to conservative therapy require a surgical approach. Arthroscopic debridement and microfracturing has become the standard initial procedure for treatment of capitellar OCD. Numerous other surgical options have been reported, including internal fixation of large fragments and osteochondral autograft transfer. The aim of this article is to provide a current concepts review of the etiology, clinical presentation, diagnosis, treatment, and outcomes of elbow OCD.

Ultrasound imaging of the humeral capitellum: a cadaveric study

BACKGROUND

Ultrasound is suitable for routine examinations of capitellar osteochondritis dissecans because it can visualize both the subchondral bone and the overlying articular cartilage non-invasively. The radial head interferes with the sonographically visible area of the articular surface of the humeral capitellum, although the precise extent of this is currently unknown. This study aimed to investigate the visible area of the humeral capitellum using both anterior and posterior ultrasonographic scans.

METHODS

Twelve elbows were used from cadavers with a mean age of 85.6 years. After marking a 45° angle in the anterior capitellum in a caudal direction using a drill, anterior and posterior, long-axis ultrasonographic scans were performed with the cadaveric elbows bent. The elbow-flexion angle at which the 45° point was obscured by the radial head was measured and these ultrasonic measurements were then verified by macroscopic observation.

RESULTS

The elbow-flexion angle at which the 45° point was obscured by the radial head was 24° in anterior scans and 102° in posterior scans. These ultrasonic measurements corresponded to the macroscopic measurements. The results showed that anterior, long-axis ultrasound scans could visualize the capitellum from 45° through the rest of the anterior area at 24° flexion of the elbow: the radial head obscured the area of the capitellum that is 21° anterior to the elbow flexion angle. Similarly, posterior long-axis scans could visualize the capitellum from 45° through the rest of the posterior area at 102° flexion of the elbow: the radial head obscured the area of the capitellum that is 57° posterior to the elbow flexion angle. The radial head obscured a 78° (21° + 57°) arc of the capitellum in ultrasonography.

CONCLUSIONS

This study thus clarified the area of the humeral capitellum visible in both anterior and posterior ultrasound scans in the sagittal plane.

Prevalence of Osteochondritis Dissecans of the Capitellum in Young Baseball Players: Results Based on Ultrasonographic Findings

BACKGROUND

Osteochondritis dissecans (OCD) of the capitellum is a well-recognized cause of elbow pain and disability in adolescent athletes. However, little is known about the prevalence of OCD in adolescent baseball players.

PURPOSE

To determine the prevalence of OCD in baseball players aged 10 to 12 years based on ultrasonographic findings and to investigate the clinical characteristics of those with OCD lesions.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

A total of 1040 players aged 10 to 12 years completed a questionnaire, ultrasound imaging, and radiographic examination to investigate OCD. Sonographic findings were classified into 5 grades (0, 1a, 1b, 2, and 3). Subjects with grade 1a, 1b, 2, or 3 were considered to have abnormal findings of the capitellum and were advised to undergo radiography. Radiographic and ultrasonographic findings were then compared. The prevalence of OCD was calculated, and differences by age and player position were determined.

RESULTS

Of the 1040 players, 33 (3.2%) had an abnormal finding on initial ultrasonography screening, and all 33 agreed to undergo radiography. Of them, 22 (66.7%) were found to have OCD of the capitellum on radiographs, giving an overall prevalence of 2.1%. Seven subjects (31.8%) had no history of elbow pain. Based on the radiographic classification, 20 subjects (90.9%) had stage I lesions. Analysis of OCD by age and player position revealed no significant differences.

CONCLUSION

The prevalence of OCD of the capitellum was 2.1% in 1000 baseball players aged 10 to 12 years, with no differences in prevalence according to age or player position.

Prevalence and Clinical Characteristics of Osteochondritis Dissecans of the Humeral Capitellum Among Adolescent Baseball Players

BACKGROUND

The prevalence and clinical characteristics of osteochondritis dissecans (OCD) of the humeral capitellum among adolescent baseball players are unknown.

PURPOSE

To determine the OCD prevalence in adolescent competitive baseball players and to investigate the clinical characteristics of these patients.

STUDY DESIGN

Cross-sectional and case-control study; Level of evidence, 3.

METHODS

A total of 2433 baseball players (mean age, 14.5 ± 1.5 years) belonging to junior high school and high school baseball clubs were enrolled. Players completed a questionnaire, and the elbow of each player's throwing arm was assessed by ultrasonography. Participants with abnormal results on ultrasonography were further examined through radiographic study. The OCD lesions were classified into stages based on radiographic results, and demographic data were compared between players with and without OCD lesions.

RESULTS

Osteochondritis dissecans of the humeral capitellum was found in 82 (3.4%) elbows by ultrasonography. Players with an OCD lesion began playing baseball at an earlier age (P = .016), had a longer duration of competitive play (P = .0013), and had experienced more present (P = .0025) and past (P < .0001) elbow pain compared with players without a lesion. There were no differences between the 2 groups in the position played (P = .26). Sixty-eight patients underwent further radiographic examination for OCD (radiography, computed tomography, magnetic resonance imaging). Of these players, 10 (14.7%) were classified as having stage I OCD (radiolucent stage); 26 (38.2%), stage II (fragmentation stage); 9 (13.2%), stage III (loose body stage); 9 (13.2%), stage IV (residual stage); and 14 (23.5%), stage V (postoperative stage).

CONCLUSION

The prevalence of OCD of the humeral capitellum, including latent cases, was 3.4% among adolescent baseball players. Players with OCD lesions began playing baseball at earlier ages, had played for longer periods, and had experienced more elbow pain. The player's current baseball position may not be related to the existence of OCD lesions in adolescents.

Preoperative imaging criteria for unstable osteochondritis dissecans of the capitellum

BACKGROUND

The stability of an osteochondritis dissecans (OCD) lesion of the humeral capitellum may be determined by intraoperative probing with unstable lesions being displaceable. Although preoperative imaging is used to diagnose and determine treatment of these lesions, it is unclear whether unstable lesions on imaging correspond to those found intraoperatively.

QUESTIONS/PURPOSES

We therefore examined the concordance between preoperative imaging and intraoperative instability and examined the imaging features of the patients who healed without surgery.

METHODS

We retrospectively reviewed 61 patients who underwent OCD of the humeral capitellum surgery or nonoperative treatment. All patients had plain radiography, MRI, and/or CT scans. The presence or absence of stability was determined intraoperatively by the International Cartilage Repair Society OCD classification. We determined the sensitivity, specificity, and predictive value of various imaging findings to predict instability.

RESULTS

The following preoperative imaging features were associated with intraoperative instability: a displaced fragment, epiphyseal closure of the capitellum, or a lateral epicondyle observed on radiographs; irregular contours of the articular surface or a high signal interface on T2-weighted MRI; and a displaced fragment observed on CT. Unstable lesions were more common when the epiphysis of the capitellum was closed. Intralesional segmentation was sensitive for detecting an unstable lesion, whereas displaced type on the radiographs and displaced fragment on the CT were specific. The following imaging findings were not seen in nonoperative patients: displaced type and closure of the epiphyseal line on radiographs, irregular contours of the articular surface, articular defects, and T2 high signal intensity interface between the fragments and their bed on the MRI or a displaced fragment on the CT.

CONCLUSIONS

Although we found high sensitivity for some preoperative findings on imaging, none reached 100% of sensitivity. Preoperative MRI related to the intraoperative assessment of stability.

LEVEL OF EVIDENCE

Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

A systematic method for evaluation of pediatric sports injuries of the elbow

We present a compartmentalized approach to sports injuries of the pediatric elbow. Lateral, medial and posterior injuries are considered separately under the unifying umbrella of the common forces projected on the elbow during sports activities and the effect on the separate growth centers and physes of the elbow.

A segmental approach to imaging of sports-related injuries of the pediatric elbow

CONTEXT

The imaging of pediatric sports injuries of the elbow requires an understanding of the interaction between biomechanical forces common in sports and the developing skeleton.

EVIDENCE ACQUISITION

A PubMed search was performed using the terms elbow, radiology, and sports with the search limited to children up to 18 years of age. No limits were set on the range of years searched. Articles were reviewed for relevance with an emphasis of the changing nature of sports injuries about the pediatric elbow.

RESULTS

A clear progression of injuries about the elbow can be identified as the skeleton matures. Sports most commonly associated with injuries in the pediatric age group were baseball and gymnastics.

CONCLUSIONS

Most pediatric sports injuries result from overhand throwing, especially in baseball or gymnastics. The manifestation of the injuries shifts as the physes progress toward closure.

Osteochondritis dissecans of the capitellum: a review of the literature and a distal ulnar portal

Osteochondritis dissecans (OCD) of the humeral capitellum most commonly affects young athletes engaged in sports that repetitively stress the elbow. It is characterized by localized injury of subchondral bone of the humeral capitellum. To determine the best treatment option for OCD in young athletes, it is important to differentiate between stable and unstable OCD lesions. Stable lesions can be treated with rest, whereas unstable lesions, as well stable lesions that do not respond to conservative therapy, may require a surgical approach. Magnetic resonance imaging is the diagnostic study of choice to evaluate capitellar OCD lesions and loose bodies and to accurately determine the stability and viability of the OCD fragment. A variety of surgical approaches have been reported, from internal fixation of large fragments to autologous chondrocyte grafts. Arthroscopic surgery is becoming the standard treatment of capitellar OCD. This minimally invasive approach shows good results, a low risk of operative morbidity, and early recuperation postoperatively. The distal ulnar portal we describe here allows for ergonomic exposure to the posterolateral capitellum, providing easier access for drilling, burring, and local debridement of lesions amenable to arthroscopy.

Osteochondritis dissecans of the capitellum: current concepts

Osteochondritis dissecans (OCD) of the capitellum is an uncommon disorder seen primarily in the adolescent overhead athlete. Unlike Panner disease, a self-limiting condition of the immature capitellum, OCD is multifactorial and likely results from microtrauma in the setting of cartilage mismatch and vascular susceptibility. The natural history of OCD is poorly understood, and degenerative joint disease may develop over time. Multiple modalities aid in diagnosis, including radiography, MRI, and magnetic resonance arthrography. Lesion size, location, and grade determine management, which should attempt to address subchondral bone loss and articular cartilage damage. Early, stable lesions are managed with rest. Surgery should be considered for unstable lesions. Most investigators advocate arthroscopic débridement with marrow stimulation. Fragment fixation and bone grafting also have provided good short-term results, but concerns persist regarding the healing potential of advanced lesions. Osteochondral autograft transplantation appears to be promising and should be reserved for larger, higher grade lesions. Clinical outcomes and return to sport are variable. Longer-term follow-up studies are necessary to fully assess surgical management, and patients must be counseled appropriately.

Osteochondritis dissecans of the capitellum

Osteochondritis dissecans of the capitellum is a well-recognized cause of elbow pain and disability in the adolescent athlete. This condition typically affects young athletes, such as throwers and gymnasts, involved in high-demand, repetitive overhead, or weightbearing activities. The true cause, natural history, and optimal treatment of osteochondritis dissecans of the capitellum remain unknown. Suspicion of this condition warrants investigation with proper radiographs and magnetic resonance imaging. Prompt recognition of this disorder and institution of nonoperative treatment for early, stable lesions can result in healing with later resumption of sporting activities. Patients with unstable lesions or those failing nonoperative therapy require operative intervention with treatment based on lesion size and extent. Historically, surgical treatment included arthrotomy with loose body removal and curettage of the residual osteochondral defect base. The introduction of elbow arthroscopy in the treatment of osteochondritis dissecans of the capitellum permits a thorough lesion assessment and evaluation of the entire elbow joint with the ability to treat the lesion and coexistent pathology in a minimally invasive fashion. Unfortunately, the prognosis for advanced lesions remains more guarded, but short-term results after newer reconstruction techniques are promising.

Risk factors for elbow injuries among young baseball players

HYPOTHESIS

There are some risk factors that could predispose a young baseball player to elbow injuries.

MATERIALS AND METHODS

Study participants were 294 baseball players aged 9 to 12 years old. A questionnaire, physical examination, and ultrasound imaging to investigate elbow injuries were performed. Data for the groups with and without elbow injuries were analyzed statistically using multivariate logistic regression models.

RESULTS

Ultrasound imaging showed that 60 participants had elbow injuries, including medial epicondylar fragmentation in 58 and osteochondritis dissecans of the capitellum in 2. The odds ratio (95% confidence interval) of the risk factors that statistical analysis showed were significant were age older than 11 years, 2.82 (1.30-6.10); height exceeding 150 cm, 2.02 (1.07-3.82); pitching, 4.50 (2.42-8.37); daily training, 1.96 (1.02-3.79); range of motion (ROM) of external rotation of the shoulder below 130 degrees , 1.98 (1.01-3.87); muscle strength (MS) of external rotation of the shoulder exceeding 80 N, 4.11 (1.47-11.55); and MS of internal rotation of the shoulder exceeding 100 N, 2.04 (1.08-3.90).

DISCUSSION

Risk factors for elbow injuries are age, height, pitcher, days of training, grip strength, range of motion of external rotation of the shoulder, and muscle strength of the shoulder.

CONCLUSION

As new information, our results suggest that decrease of ROM of external rotation of the shoulder and increase of MS of external and internal rotation of the shoulder predispose elbow injuries.

Nonoperative treatment for osteochondritis dissecans of the capitellum

BACKGROUND

Spontaneous healing potential and progression of osteochondritis dissecans of the capitellum have been unclear.

HYPOTHESIS

Healing potential is high in the early stage of osteochondritis dissecans and low in the advanced stage.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This retrospective study examines 39 patients with osteochondritis dissecans of the capitellum who were treated conservatively. All patients were baseball players (mean age, 12.8 years). After initial examination, all patients were advised to stop heavy use of the elbow. Physical and radiographic examinations were regularly performed and assessed. Mean duration of follow-up was 14.4 months.

RESULTS

Early-stage lesions were present in 30 patients, while 9 patients were diagnosed with advanced lesions. Open capitellar growth plates were observed in 17 patients, and closed capitellar growth plates were seen in 22 patients. On final radiography, 25 of 30 early-stage lesions were assessed as healed. However, only 1 of 9 advanced-stage lesions was assessed as healed. The remaining 8 advanced lesions were unimproved or progressed. Healing of lesions was seen in 16 of 17 patients with an open growth plate and in 11 of 22 patients with a closed growth plate, representing a significant difference between patients with open and closed growth plates (P < .05).

CONCLUSION

Spontaneous healing potential of osteochondritis dissecans in early lesions, especially in patients with open capitellar growth plates, appears high, and nonoperative treatment is appropriate. Conversely, healing potential is extremely low in advanced osteochondritis dissecans lesions. Surgical intervention is recommended to achieve lesion healing in advanced cases.

Classification, treatment, and outcome of osteochondritis dissecans of the humeral capitellum. Surgical technique

BACKGROUND

Indications for the treatment of osteochondritis dissecans of the humeral capitellum have remained unclear. The aims of this study were to analyze the outcomes and to determine the most useful classification for the choice of treatment.

METHODS

The cases of 106 patients with osteochondritis dissecans of the capitellum were studied retrospectively. At the time of the initial presentation, the mean age of the patients was 15.3 years. The capitellar growth plate was open in eighteen patients and closed in eighty-eight. Thirty-six patients were treated nonoperatively. Fifty-five patients underwent fragment removal alone, twelve underwent fragment fixation with a bone graft, and three underwent reconstruction of the articular surface with use of osteochondral plug grafts from the lateral femoral condyle. The mean follow-up period was 7.2 years. The outcomes in terms of pain in the elbow, return to sports, and radiographic findings were analyzed and compared.

RESULTS

An osteochondritis dissecans lesion with an open capitellar physis and a good range of elbow motion resulted in a good outcome. Continued elbow stress resulted in the worst outcome in terms of pain and radiographic findings. In patients with a closed capitellar physis, surgery provided significantly better results than elbow rest (p < 0.01). Fragment fixation or reconstruction provided significantly better results than fragment removal alone (p < 0.05). The results of removal alone were dependent on the size of the defect in the capitellum. The outcome in terms of pain was closely associated with sports activity and radiographic findings.

CONCLUSIONS

We believe that osteochondritis dissecans of the capitellum can be classified as stable or unstable. Stable lesions that healed completely with elbow rest had all of the following findings at the time of the initial presentation: an open capitellar growth plate, localized flattening or radiolucency of the subchondral bone, and good elbow motion. Unstable lesions, for which surgery provided significantly better results, had one of the following findings: a capitellum with a closed growth plate, fragmentation, or restriction of elbow motion of >or=20 degrees . For large unstable lesions, fragment fixation or reconstruction of the articular surface leads to better results than simple excision.

Osteochondritis dissecans of the knee: sonographically guided percutaneous drilling

OBJECTIVE

The purpose of this study was to present a procedure for sonographically guided percutaneous drilling in the treatment of a case of osteochondritis dissecans (OD) of the knee.

METHODS

A 14-year-old boy had OD of the external femoral condyle. Conventional radiography, magnetic resonance imaging, and sonography revealed the osteochondral lesion.

RESULTS

This study showed the utility of sonography both in the treatment of OD through percutaneous drilling and in follow-up.

CONCLUSIONS

On the basis of the good results obtained in the case described here, it is thought that sonographically guided percutaneous drilling may be a good alternative to arthroscopic drilling in cases of early OD lesions without displacement of the fragment.

Classification, treatment, and outcome of osteochondritis dissecans of the humeral capitellum

BACKGROUND

Indications for the treatment of osteochondritis dissecans of the humeral capitellum have remained unclear. The aims of this study were to analyze the outcomes and to determine the most useful classification for the choice of treatment.

METHODS

The cases of 106 patients with osteochondritis dissecans of the capitellum were studied retrospectively. At the time of the initial presentation, the mean age of the patients was 15.3 years. The capitellar growth plate was open in eighteen patients and closed in eighty-eight. Thirty-six patients were treated nonoperatively. Fifty-five patients underwent fragment removal alone, twelve underwent fragment fixation with a bone graft, and three underwent reconstruction of the articular surface with use of osteochondral plug grafts from the lateral femoral condyle. The mean follow-up period was 7.2 years. The outcomes in terms of pain in the elbow, return to sports, and radiographic findings were analyzed and compared.

RESULTS

An osteochondritis dissecans lesion with an open capitellar physis and a good range of elbow motion resulted in a good outcome. Continued elbow stress resulted in the worst outcome in terms of pain and radiographic findings. In patients with a closed capitellar physis, surgery provided significantly better results than elbow rest (p < 0.01). Fragment fixation or reconstruction provided significantly better results than fragment removal alone (p < 0.05). The results of removal alone were dependent on the size of the defect in the capitellum. The outcome in terms of pain was closely associated with sports activity and radiographic findings.

CONCLUSIONS

We believe that osteochondritis dissecans of the capitellum can be classified as stable or unstable. Stable lesions that healed completely with elbow rest had all of the following findings at the time of the initial presentation: an open capitellar growth plate, localized flattening or radiolucency of the subchondral bone, and good elbow motion. Unstable lesions, for which surgery provided significantly better results, had one of the following findings: a capitellum with a closed growth plate, fragmentation, or restriction of elbow motion of > or =20 degrees . For large unstable lesions, fragment fixation or reconstruction of the articular surface leads to better results than simple excision.

LEVEL OF EVIDENCE

Prognostic Level II.

Using sonography for the early detection of elbow injuries among young baseball players

OBJECTIVE

The aim of this study was to determine the usefulness of sonography for detecting elbow injuries among young baseball players.

SUBJECTS AND METHODS

One hundred fifty-three volunteers ranging in age from 9 to 12 years and belonging to youth baseball teams participated. Sonography of the elbow was performed in the field when baseball exercises were being conducted. We analyzed the relationship between elbow pain and sonographic abnormalities and the relationship between pitchers and sonographic abnormalities.

RESULTS

Sonography showed that 33 subjects had medial epicondylar fragmentation and two had early-stage osteochondritis dissecans of the capitellum. In 25 subjects who agreed to further examination and treatment, radiography confirmed the sonographic findings. All of the 23 subjects with medial epicondylar fragmentation, who stopped throwing, obtained union of the bone and returned to baseball. The two subjects with osteochondritis dissecans of the capitellum underwent surgery before the osteochondral fragment became loosened. Sonographic abnormalities correlated with episodes of elbow pain. Pitchers statistically significantly had sonographic abnormalities.

CONCLUSION

Sonography in the field can provide an opportunity to detect and treat elbow injuries before they become more advanced.

Osteochondritis dissecans of the elbow: Histopathological assessment of the articular cartilage and subchondral bone with emphasis on their damage and repair

Osteochondritis dissecans (OCD) of the elbow is a localized injury of the articular cartilage and subchondral bone that is commonly seen in the young athlete. In the present study, the extent of damage and repair on the articular cartilage and subchondral bone was examined histologically using specimens of 25 osteochondral cylinders and seven loose bodies obtained from 25 young athletes who had undergone osteochondral autograft surgery. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) assays for detecting apoptotic cells and immunohistochemistry of matrix metalloproteinases (MMP) were performed on the osteochondral cylinder specimens. The histological findings of the OCD of the elbow showed that the articular cartilage exhibited degenerative change, mimicking osteoarthritis, and was markedly damaged as the lesion progressed. TUNEL-positive cells and MMP-3- and -13-expressing cells were distributed in the degenerative articular cartilage and reparative fibrocartilage tissue. Separation occurred at either the deep articular cartilage or the subchondral bone, with the former being dominant in the early OCD lesions. The present results suggest that the primary pathological changes in OCD of the elbow were due to damage of articular cartilage induced by repeated stress following degenerative and reparative process of articular cartilage and subchondral fracturing, and separation subsequently occurred on the cartilage and developed onto the subchondral bone in its advanced stages.

Imaging of sports injuries of the upper extremity in children

Competitive athletics in school-aged children has become the norm rather than the exception. The increased repetitive stresses placed on the upper extremity in a wide variety of sports result in a host of injuries unique to the skeletally immature athlete. This article focuses on a discussion of the more common upper extremity injuries encountered in the child athlete and the role of radiography and MRI in diagnosis and management.

COMPARISON OF THE ULTRASONOGRAPHIC APPEARANCE OF OSTEOCHONDROSIS LESIONS IN THE CANINE SHOULDER WITH RADIOGRAPHY, ARTHROGRAPHY, AND ARTHROSCOPY

Osteochondrosis lesions in 29 shoulder joints (from 20 dogs) were evaluated with ultrasound (US) and the results were compared with survey radiography, arthrography, and arthroscopy. US was performed with a 7-12 MHz linear matrix transducer which was placed in cranio-caudal direction just distally to the acromion while the joint was adducted and maximally endorotated to visualize the caudal aspect of the humeral head. With US, the subchondral defect was completely visible in 21 joints and partially visible in 8 joints. The length of the subchondral defect measured on US was comparable with the length measured on survey radiographs. In two joints, the cartilage flap was mineralized and thus already visible on survey radiographs. The mineralized flap was visible on US as a straight hyperechoic line above the subchondral defect. In the other joints, survey radiographs could not assess the status of the articular cartilage. In 17 joints, the presence of a cartilage flap or cartilage fissuring was suspected based on the presence of a second hyperechoic line at the base of the subchondral defect, and this suspicion was confirmed by arthroscopic examination in 16 joints and also by arthrographic examination in 15 joints. One joint that was suspected of having a cartilage flap on US was normal on arthroscopy and arthrography. When US revealed only focal thickening of the anechoic cartilage layer (5 joints), the joints appeared normal on arthroscopic and arthrographic examination. Of the four joints where the subchondral defect was irregular and covered by heteroechogeneous material on US, arthroseopy revealed the presence of a lesion resembling chondromalacia in two joints, the presence of a small cartilage flap in one joint and the presence of scar tissue underneath the flap at the level of the subchondral defect in one joint. In conclusion, US is a helpful imaging modality in the identification of osteochondritic lesions in the canine shoulder joint. US also appears to be a satisfactory imaging tool for identifying lesions such as joint mice, joint effusion, and distinct new bone formation.

Lateral compression injuries in the pediatric elbow: Panner's disease and osteochondritis dissecans of the capitellum

Lateral compression injuries of the elbow typically occur in throwing athletes and gymnasts. In the preadolescent and adolescent patient, these injuries predominantly include Panner's disease and osteochondritis dissecans. Panner's disease, an osteochondrosis of the capitellum, is a rare disorder that usually affects the dominant extremity in individuals younger than age 10 years. Symptomatic management of Panner's disease consisting of reduction of stressful activities of the elbow is usually sufficient to allow resolution. Although a prolonged period is required for healing, most patients demonstrate excellent long-term results. Osteochondritis dissecans of the capitellum typically occurs in adolescents and is associated with loose body formation. Panner's disease and osteochondritis dissecans likely represent a continuum of disordered endochondral ossification with presentation and prognosis dependent primarily on age at onset.