Exertional Lower Extremity Pain in a Triathlete Caused by External Iliac Artery Endofibrosis: A Case Report.

Case: This report describes a 25-year-old female professional triathlete with right external iliac artery endofibrosis (EIAE) that was definitively diagnosed on contrast-enhanced magnetic resonance images obtained immediately after treadmill running. The EIAE was treated by percutaneous transluminal angioplasty. By 8 weeks after surgery, she had no symptoms of claudication or pain in the right thigh after a 1-hour running session.

Chronological changes in the rate of surgical field contamination in the shoulder joint.

Background: In shoulder surgery, low-virulence bacteria such as Cutibacterium acnes and coagulase-negative staphylococci can cause postoperative infection. However, the degree of sterility during surgery after disinfection is not known, and the efficacy of double skin preparation for such bacteria is unclear. This study aimed to evaluate chronological changes in the surgical field contamination rate in the shoulder joint and to compare single and double skin preparation.

Primary synovial chondromatosis of the shoulder followed for 11 years after arthroscopic surgery: A case report.

We report a case of primary synovial chondromatosis of the shoulder (Milgram classification, stage III) in a 25-year-old woman. She underwent arthroscopic removal of multiple loose bodies and partial synovectomy. Histological findings revealed primary synovial chondromatosis.

Quadratus lumborum muscle strain in a youth soccer player: a case report.

We report a case of quadratus lumborum muscle strain that occurred in a 16-year-old soccer player during a game. According to a video recording of the game, the injury occurred when the leg landed just after kicking the ball with the same leg while dribbling. The mechanism was suspected to be right lateral flexion of the trunk while the pelvis was simultaneously forced to tilt backward.

Signal intensity on MRI after conservative treatment of patients with full-thickness rotator cuff tears: Correlation with shoulder pain.

Background: High signal intensity (HSI) on T2-weighted or fat-suppressed magnetic resonance imaging (MRI) around the shoulder is often observed in patients who have a rotator cuff tear, and is generally recognized as an indicator of shoulder pain, especially pain at night. We hypothesized these HSI volumes are reduced after improvement of symptoms. We sought to compare HSI before and after conservative treatment, and to determine if HSI is associated with the patient's pain status over time.

Age-related differences in glenohumeral internal rotation deficit, humeral retrotorsion angle, and posterior shoulder tightness in baseball players.

Background: Glenohumeral internal rotation deficit is generally recognized as a risk factor for throwing disability in baseball players. However, the pathology, timing of onset, role in the onset of humeral retrotorsion angle (HTA) and soft tissue extensibility (STE), and the relationship with age remain unclear. Therefore, the purpose of this cross-sectional study was to investigate age-related glenohumeral internal rotation deficit, HTA, and STE in Japanese baseball players and determine whether these factors correlate with throwing disability.

Risk assessment of the onset of Osgood-Schlatter disease using kinetic analysis of various motions in sports.

Background: Some studies have listed motions that may cause Osgood-Schlatter disease, but none have quantitatively assessed the load on the tibial tubercle by such motions.

Purposes: To quantitatively identify the load on the tibial tubercle through a biomechanical approach using various motions that may cause Osgood-Schlatter disease, and to compare the load between different motions.

Methods: Eight healthy male subjects were included.

Efficacy of autologous leukocyte-reduced platelet-rich plasma therapy for patellar tendinopathy in a rat treadmill model.

Background: An autologous platelet-rich plasma (PRP) therapy has currently been applied for the tendinopathy; however, its efficacy and an optimal platelets concentration in PRP were uncertain. We analyzed them in an animal model prepared using a repetitive running exercise.

Methods: We made the tendinopathy rat model of patellar tendon using a rodent treadmill machine.

Arthroscopic Release of Flexor Hallucis Longus Tendon Sheath in Female Ballet Dancers: Dynamic Pathology, Surgical Technique, and Return to Dancing Performance.

Stenosing tenosynovitis of the flexor hallucis longus (FHL) tendon is known as a major overuse lesion in female dancers. We describe arthroscopic surgical techniques in relation to the dynamic pathology of the disease. Crepitus and pain on moving the great toe with the ankle in plantar flexion on preoperative examination confirm the diagnosis of FHL stenosing tenosynovitis even if the os trigonum is not evident.

Arthroscopic reduction and internal fixation for fracture of the lateral process of the talus.

Fractures of the lateral process of the talus (LPT) are relatively rare. We describe arthroscopic reduction and internal fixation for a type I fracture of the LPT according to the Hawkins classification. Preoperative computed tomography is necessary to evaluate the type and displacement of the LPT fracture because this type of fracture is often overlooked on a plain radiograph.

Therapeutic effects of high molecular weight hyaluronan injections for tendinopathy in a rat model.

Background: Tendinopathy is the most common tendon disorder. The etiology is still uncertain, and the disorder poses many therapeutic problems. In a few clinical studies, analgesic effects of high molecular weight hyaluronan (HMW HA) injections were observed, but the underlying mechanisms were not elucidated.

Arthroscopic excision of bone fragments in a neglected fracture of the lateral process of the talus in a junior soccer player.

Fractures of the lateral process of the talus are uncommon and often overlooked. Typically, they are found in adult snowboarders. We report the case of an 11-year-old male soccer player who complained of lateral ankle pain after an inversion injury 6 months earlier.

Distinctive collagen maturation process in fibroblasts derived from rabbit anterior cruciate ligament, medial collateral ligament, and patellar tendon in vitro.

Purpose: Differences in the tissue-specific collagen maturation process between tendon and ligament are still unknown. Collagen cross-link formation is crucial for the collagen maturation process. The aim of this study is to examine collagen maturation processes of anterior cruciate ligament (ACL), medial collateral ligament (MCL), and patellar tendon (PT) in vitro, in order to determine the optimal cell source for tissue engineering of ligament.

Incomplete joint side tear of the subscapularis tendon with a small fragment in an adolescent tennis player: a case report.

Case: In this case report, we presented the case of an adolescent tennis player with avulsion injury of the subscapularis tendon of the right shoulder.

Patients: A 17-year-old right-hand-dominant male tennis player visited our hospital complaining of pain in the anterior aspect of the right shoulder. We performed X-ray and three-dimensional computed tomography (3D-CT) and magnetic resonance imaging (MRI) scans for the diagnosis.

Analysis for the major contributor of collagenase to the primary cleavage of type II collagens in cartilage degradation.

Degradation of type II collagen is a central process in cartilage destruction seen in osteoarthritis and rheumatoid arthritis. Primary cleavage of type II collagen at the collagenase site is rate-limiting and is, therefore, a critical step for its degradation. The major contributor to this cleavage was identified in three isozymes of collagenase in human cartilage.