Ryuhei Furukawa

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.

Diagnostic accuracy of magnetic resonance imaging for subscapularis tendon tears using radial-slice magnetic resonance images

BACKGROUND Magnetic resonance imaging has low diagnostic accuracy for subscapularis tendon tears. This study investigated the utility of radial-slice magnetic resonance images for diagnosing subscapularis tendon tears. MATERIALS AND METHODS We investigated 55 shoulders in 54 patients with rotator cuff tears evident during arthroscopic shoulder surgery. The intraoperative finding of a subscapularis tendon tear was compared with the identification of a subscapularis tendon tear on preoperative radial, transverse, and oblique sagittal images using a 3.0-T system. The sensitivity and specificity of diagnostic images generated using different imaging methods for subscapularis tendon tears were investigated. RESULTS A subscapularis tendon tear was present in 38 shoulders (69.1%). When the diagnostic accuracy of the magnetic resonance images was compared with the arthroscopic findings, the radial images had 94.7% sensitivity and 82.4% specificity, the transverse images had 57.9% sensitivity and 100% specificity, and the oblique sagittal images had 60.5% sensitivity and 100% specificity. CONCLUSION Radial-slice magnetic resonance images have high sensitivity for subscapularis tendon tears and are useful for diagnosing these lesions. In particular, the sensitivity for tears in the superior part of the subscapularis tendon is higher than that of conventional methods.

Clinical application of radial magnetic resonance imaging for evaluation of rotator cuff tear

BACKGROUND Magnetic resonance imaging is useful for evaluating the rotator cuff, but some tendinous insertions cannot be assessed using oblique sagittal, oblique coronal, and axial magnetic resonance (MR) images because of the presence of the partial volume effect. HYPOTHESIS The purpose of this study was to determine whether radial-slice MR images could reveal normal rotator cuff insertions and rotator cuff tears more clearly than conventional MR images. PATIENTS AND METHODS The study included 18 subjects with normal rotator cuffs and 30 with rotator cuff tears. MR images of rotator cuff insertions sliced into radial, oblique coronal, and axial sections were obtained. The extent to which normal rotator cuff insertions and rotator cuff tears were visualized in each of the three MR images was evaluated. RESULTS The top to posterior portions of the rotator cuff insertions from 0° to 120° could be visualized in the radial MR images. In comparison, the posterior portions of the rotator cuff insertions could not be visualized around 45° in both the oblique coronal and axial MR images. DISCUSSION These findings demonstrate that radial MR images are superior to the oblique coronal and axial MR images regarding their ability to accurately visualize rotator cuff insertions. Radial MR images also revealed greater detail around 45° in the posterior area of the rotator cuff tears than the oblique coronal and axial MR images. Radial MR images are particularly useful for visualizing clinically important posterosuperior rotator cuff tears. LEVEL OF EVIDENCE Level III - Diagnostic study.

Arthroscopic decompression with indigo carmine for treating paralabral cysts in the shoulder

Paralabral cysts in the shoulder are a relatively rare pathology. It is sometimes difficult to detect the location of a paralabral cyst in the shoulder using arthroscopy, and it can be difficult to confirm sufficient decompression by arthroscopy. We describe the case of a 64-year-old woman who underwent arthroscopic decompression for a paralabral cyst in the shoulder. Indigo carmine was injected into the cyst under ultrasonography guidance just before the operation. The leakage point of indigo carmine was detected using arthroscopy. Arthroscopic decompression was performed until the indigo carmine was completely discharged. Her shoulder pain, limited range of motion, and muscle weakness during abduction and external rotation improved postoperatively. Magnetic resonance imaging confirmed the disappearance of the cyst. Arthroscopic decompression using an ultrasonography-guided injection of indigo carmine is a useful treatment for a paralabral cyst in the shoulder.

Vascularity Visualized by Doppler Sonography as a Predictor of Healing Potential of the OCD of the Humeral Capitellum

Objectives: The significance of vascularity visualized by Doppler sonography in osteochondritis dissecance (OCD) lesion of the humeral capitellum is unclear. The objectives of this study were twofold: 1) to evaluate the relationship between Doppler ultrasound (US) signals observed in OCD lesion of the humeral capitellum and X-ray stage; 2) to determine if the presence of Doppler US signals in OCD lesion of the humeral capitellum could be the predictor of healing potential. Methods: Fifty patients with OCD of the humeral capitellum treated conservatively were enrolled in this study. During the conservative treatment period, Doppler sonography was performed on affected elbow to assess the presence of vascularity in the OCD lesion (Figure 1), and radiographic examination were evaluated on the same day to determine the X-ray stage (stage I: radiolucent stage, stage II: fragmentation stage, and stage III: loose body stage) of the OCD lesion (Figure 2). Radiographic examination of the elbow was examined after 6 weeks to evaluate the healing of the lesion. If the size of the lesion decreased or new bone formations were observed around the fragments, the healing of the lesion was considered to be improve. The χ2 test was used to determine if the presence of Doppler US signals were related to X-ray stage and the improvement of the healing. P < 0.05 was considered significant for all statistical analyses. Results: The Doppler US signals in OCD lesions were positive in 23 patients and negative in 27 patients. Of these patients, 19 were X-ray stage I, 17 were stage II, and 9 were stage III. The healing of OCD lesions improved in 78.2% for the positive Doppler US signal group, but only 18.5% for the negative Doppler US signal group (Figure 3). The presence of the Doppler US signal was significantly related to the improvement of healing (P = 0.00002). The Doppler US signal were positive in 78.9% for stage I, 36.4% for stage II, and 0.0% for stage III (Figure 4). The presence of Doppler US signal was significantly related to early X-ray stage (P = 0.0002). Conclusion: From this study, the presence of vascularity in the OCD lesion of the humeral capitellum is important for the improvement of healing during the conservative treatment period. The vascularity visualized by Doppler sonography could be a useful predictor for healing potential of the OCD of the humeral capitellum when treated conservatively.

Prevalence of posterior elbow problems in Japanese high school baseball players

BACKGROUND Various posterior elbow problems cause posterior elbow pain among baseball players. We aimed to determine the prevalence and diagnoses associated with posterior elbow problems and post-treatment recovery time for returning to sports in Japanese high school baseball players when treated in the off-season. METHODS A total of 576 Japanese high school baseball players who participated in baseball skill training camp during the off-season were enrolled in the study. The elbow of each players throwing arm was assessed by use of a questionnaire and physical examination. Players with abnormal results were advised to visit the hospital. Players who visited the hospital were initially treated conservatively and underwent surgery if necessary. Retrospectively, players with positive physical examination results associated with posterior elbow pain, defined as olecranon tenderness and/or a positive elbow extension impingement test, were selected. Information about their position, elbow pain, physical examination results, diagnosis, treatment, and recovery time before returning to playing sports was assessed. RESULTS Olecranon tenderness and/or positive elbow extension impingement test results were found in 76 players (13.2%). Of these, 33 agreed to visit the hospital for further diagnostic imaging and 25 players (75.8%) were diagnosed with posteromedial elbow impingement. By the next spring, 87.9% of players returned to sport, and 100% of players returned to sport before the next summer. The average recovery period was 77 ± 47 days. CONCLUSION Physical examinations related to posterior elbow injuries were positive in 13.2% of high school baseball players. The most common diagnosis for posterior elbow pain was posteromedial elbow impingement. All players returned to competitive sports activity levels within 77 ± 47 days.

Visualization of rotator cuff tear morphology by radial magnetic resonance imaging

The objective of this study was to investigate whether rotator cuff tear morphology could be visualized using radial MRI. We retrospectively investigated 52 shoulders that underwent preoperative MRI and arthroscopy for a complete rotator cuff tear. The tear length and width were measured using oblique coronal, axial, and radial MRI. Arthroscopic findings were compared with the tear morphology. Tear morphology was visualized using oblique coronal and axial MRI for 24 of the 52 shoulders (46%), and radial MRI for all 52 shoulders. Radial MRI data for 49 of 52 shoulders (94%) were concordant with the arthroscopic findings.

Validity of radial magnetic resonance imaging to determine the extent of Bankart lesions

PURPOSE The objectives were to compare conventional oblique coronal and axial images with radial images to determine the capacities of these modalities for visualizing sites in the glenoid labrum. MATERIALS AND METHODS The glenoid labra of 45 patients without a labrum injury and 30 patients with Bankart lesions were examined by magnetic resonance imaging using three different sections. RESULTS The radial images permitted a greater range of assessment of the morphology of the glenoid labrum than the conventional images. CONCLUSION Radial magnetic resonance imaging is a useful method for evaluation of the glenoid labrum and enables wider visualization than conventional methods.

Experience Rate of Elbow Pain and Morphological Abnormality of Humeral Medial Epicondyle among Youth Baseball Players

Objectives: The aim of this study was to investigate the experience rate of elbow pain and to clarify the relationship between morphological abnormality of the humeral medial epicondyle and positions among baseball players in elementary school (ES), junior high school (JHS) and high school (HS). Methods: In this study, 4353 baseball players who participated in our medical screening (2008-2015) were enrolled. There were 1545 players from ES, 1934 players from JHS, and 874 players from HS. We asked them to answer the questionnaire to investigate the experience of elbow pain, and the position they played. Ultrasonography of the humeral medial epicondyle was examined and irregularity, fragmentation, and malunion of the humeral medial epicondyle. The results were analyzed statistically. P < 0.05 was considered significant for all statistical analyses. Results: The experience rates of elbow pain among players in ES, JHS, and HS were 26.0%, 27.0%, and 68.3%. The rates of abnormality of humeral medial epicondyle among players in ES, JHS, and HS were 18.2%, 36.3%, and 39.9% (Table 1). The experience rate of elbow pain among pitchers and catchers was significantly higher than the fielders in ES (Table 2), however, there were no significant differences between positions in JHS and HS (Table 3,4). According to the rate of morphological abnormalities of humeral medial epicondyle, pitchers and catchers were significantly higher than fielders in ES, while only pitchers were significantly higher than the fielders in JHS and HS (Table 2,3,4). Conclusion: The experience rate of elbow pain among baseball players rose as the age increased, and the rate in HS was almost 70%. The rates of morphological abnormality of humeral medial epicondyle among pitchers and catchers were high and the tendency was observed from a young age. The primary prevention of elbow injuries in youth baseball players of all ages should be considered.