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. There has been no recurrence in 1 year postoperatively. CONCLUSION: EIAE is a rare condition and difficult to diagnose in a timely manner because symptoms and radiographic imaging features appear only during intense exercise. Our patient was successfully treated with percutaneous transluminal angioplasty.

Analysis of Quadriceps Muscle Tightness as a Risk Factor for Osgood-Schlatter Disease: A Prospective Cohort Study.

Background: The prevalence of Osgood-Schlatter disease (OSD) is unknown. Tightness of the quadriceps femoris has been reported to be a risk factor for OSD. Hypothesis: Quadriceps muscle tightness would not contribute to the development of OSD. Study Design: Cohort study; Level of evidence, 2. Methods: We enrolled 150 Japanese male junior high school soccer players (N = 300 knees), with a mean age at first examination of 12.5 years (range, 12-13 years). All players were assessed annually and evaluated for 2 years. Ten players (n = 14 knees) had a history of OSD before the first medical examination. After excluding these 10 players (n = 20 knees), the remaining 140 players (n = 280 knees) were included in this prospective analysis. Age at the time of starting soccer, history of injury (including OSD and time missed), height, weight, annual increase in height, body mass index (BMI), straight-leg raise angle, heel-buttock distance (HBD), and ultrasound images of the tibial tuberosity (maturity and morphology) were compared between players who developed OSD and those who did not. Results: OSD was identified in 8 knees of 6 players, with an incidence of 2.9% of knees (8/280) and 4.3% of players (6/140). Univariate analysis revealed significant differences between the OSD and non-OSD groups regarding BMI (17.1 ± 1 kg/m2 vs 18.5 ± 1.6 kg/m2, respectively; P = .018), HBD (1.5 ± 1.6 cm vs 4.8 ± 4.5 cm; P < .001), and stage of tibial tuberosity maturity (P < .001). The maturity of the tibial tuberosity was the only independent risk factor for the development of OSD in multivariate logistic regression analysis (odds ratio, 9.848 [95% CI, 3.297-29.41]; P < .001). Conclusion: Study findings indicated that quadriceps muscle tightness did not contribute to the development of OSD.

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. METHODS: In total, 126 shoulders in 121 patients undergoing shoulder surgery (64 men, 62 women; mean age 64 years) were enrolled. Patients were divided into two groups: single skin preparation, where the site was painted with 10% povidone iodine, and double skin preparation, where the site was treated with 1% chlorhexidine gluconate/83% isopropyl alcohol and painted 10% povidone iodine. Swab samples from the axillary and proximal areas in the surgical field were collected chronologically before starting surgery and at 30, 60, and 120 min after starting surgery (MAS). The contamination rate of each sample was compared and detected species were evaluated. RESULTS: The contamination rate for the axillary area was 48.4%, 85.9%, 95.3%, and 97.1% in the single-preparation group and 32.3%, 72.6%, 87.1%, and 91.2% in the double-preparation group before starting surgery and 30, 60, and 120 MAS, respectively, and that the proximal area was 12.5%, 26.6%, 29.7%, and 35.3% in the single-preparation group and 16.1%, 19.4%, 27.4%, and 38.2% in the double-preparation group, respectively. Significant differences were not seen between the groups by area or time point. Most detected species were Cutibacterium acnes and coagulase-negative staphylococci. CONCLUSIONS: The incidence of surgical field contamination in shoulder joint was high from immediately after starting surgery. In the axillary area, the contamination rates exceeded 70% from 30 MAS in both groups. Measures against infection should be instituted considering these findings when performing shoulder surgery.

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. Eleven years after surgery, the clinical results have been excellent with no recurrence, although X-ray showed slight degenerative changes of the glenohumeral joint. This is the first report of primary synovial chondromatosis of the shoulder observed over a 10-year follow-up period after arthroscopic surgery.

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. METHODS: We enrolled 55 patients (average age 65 years) into the study. All the patients complained of pain at night (University of California, Los Angeles (UCLA) pain score ≤2, Japanese Orthopedic Association (JOA) pain score ≤10) at their initial visits and underwent conservative treatment. MRI was obtained at their initial visit and after improvement of pain when their initial UCLA pain score was ≥6 points or JOA pain score was ≥20 points. The mean time between the MRI examinations was 11.8 months (SD 7.7) (range 2.5-39). HSI was assessed at the location of the subacromial-subdeltoid bursa, glenohumeral joint, subcoracoid bursa, and sheath of the long head of the biceps tendon, and graded. Factors correlating with the improvement of MRI findings were evaluated retrospectively. RESULTS: HSI had improved in 30 shoulders in all or some of the locations (I-group). There was no change in 25 shoulders for any location or aggravation in one or more locations (N-group). Multivariate logistic regression analysis found that the time from pain improvement until the second MRI was the only independent factor related to the improvement in HSI (p = .045). CONCLUSION: Improvement of shoulder symptoms is not directly associated with MRI findings. Improvement in HSI followed symptom improvement after a delay; the changes varied for each shoulder location.

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

Case: 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. The injury healed and he was able to return to competition 3 weeks later.Conclusion: This is the first report of a sports-related quadratus lumborum muscle strain.

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. METHODS: Participants were 172 male baseball players divided into a symptomatic group (n = 68) and an asymptomatic group (n = 104). The mean age at examination was 15.4 ± 3.2 (range, 8-22) years. Measurement items were range of motion of bilateral internal and external rotation at 90° abduction (2ndIR and 2ndER, respectively), bilateral HTA, and posterior shoulder muscle elasticity. Correlations of age, symptom, and dominance with these measurements were investigated, and significant bilateral differences in HTA and STE by age and symptom were analyzed. RESULTS: HTA and 2ndER of the dominant side were significantly greater than those of the nondominant side in those over the age of 13 years in both the asymptomatic and symptomatic groups. In contrast, 2ndIR of the dominant side was significantly smaller than that of the nondominant side in those over the age of 13 years in both the asymptomatic and symptomatic groups. The difference in HTA between the dominant and nondominant sides increased and then plateaued at 12° after the age of 16 years. STE was observed only in the symptomatic group, and the value of STE was significantly greater in players aged >16 years compared with that in players aged <12 years (P = .001). Muscle elasticity did not differ significantly between sides and showed no correlation with STE. CONCLUSIONS: The difference in HTA between the dominant and nondominant sides increased with age until 16 years old regardless of symptoms. STE in the dominant side was observed only in symptomatic baseball players after the age of 13 years and increased with age, plateauing around the age of 16 years. Posterior shoulder muscle elasticity was not indicated as a cause of STE.

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. They conducted 4 types of kicks with a soccer ball, 2 types of runs, 2 types of squats, 2 types of jump landings, 2 types of stops, 1 type of turn, and 1 type of cutting motion. The angular impulse was calculated for knee extension moments ≥1.0 Nm/kg, ≥1.5 Nm/kg, ≥2.0 Nm/kg, and ≥2.5 Nm/kg. After analysis of variance, the post-hoc test was used to perform pairwise comparisons between all groups. RESULTS/CONCLUSIONS: The motion with the highest mean angular impulse of knee extension moment ≥1.0 Nm/kg was the single-leg landing after a jump, and that with the second highest mean was the cutting motion. At ≥1.5 Nm/kg, ≥2.0 Nm/kg, and ≥2.5 Nm/kg, the cutting motion was the highest, followed by the jump with a single-leg landing. They have a large load, and are associated with a higher risk of developing Osgood-Schlatter disease. The mean angular impulse of the 2 types of runs was small at all the indicators. CLINICAL RELEVANCE: Motions with a high risk of developing Osgood-Schlatter disease and low-risk motions can be assessed in further detail if future studies can quantify the load and number of repetitions that may cause Osgood-Schlatter disease while considering age and the development stage. Scheduled training regimens that balance load on the tibial tubercle with low-load motions after a training day of many load-intensive motions may prevent athletes from developing Osgood-Schlatter disease and increase their participation in sports.

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. Rats with tendinopathy were injected with leukocyte-reduced PRP at the platelets concentration of 1.0×106/µL (P10 group), PRP at the platelets concentration of 5.0×105/µL (P5 group) or normal saline (control group) into the space between the patellar tendon and the fat pad bilaterally or were multiply dry-needled at the tibial insertion site (MN group) at once. To assess the pain-reliving effect, the spontaneous locomotor activities at night (12 h) were measured every day. Histological sections of the patellar tendon stained with hematoxylineosin or prepared by TdT-mediated dUTP nick end labeling were microscopically analyzed. RESULTS: The numbers of spontaneous locomotor activities in the P10 group were significantly larger than those in the P5, MN or control groups and they recovered up to a healthy level. On histologic examinations, the numbers of microtears, laminations, or apoptotic cells in the patellar tendons in the P10 or P5 groups were significantly lower than those in the MN or control groups, although no significant differences were observed between the P10 and P5 groups. CONCLUSIONS: The injections of an autologous leukocyte-reduced PRP were effective for pain relief and for partial restoration of the patellar tendon in the tendinopathy rat model. The injections of a PRP at the platelets concentration of 1.0×106/µL completely relieved the pain and were more effective than those at the platelets concentration of 5.0×105/µL whereas there was no difference for the effect of histological restoration or apoptosis inhibition between them.

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. The ankle is approached through a standard medial portal as the working portal and an anterolateral portal as the viewing portal. A 2.7-mm-diameter 30° arthroscope is used. Hematoma and soft tissues around the talus are cleared with a motorized shaver, and the anterior and lateral aspects of the talar process are visualized. Fracture reduction is obtained by pushing the lateral fragment of the lateral process medially and is fixed temporally with a 1.1-mm guidewire from the medial portal under both arthroscopy and fluoroscopy. A headless compression screw is inserted through the guidewire. Arthroscopic reduction and internal fixation for a type I LPT fracture can be easily accomplished, and return to daily and sports activities can be achieved in a relatively short time.

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. The ankle is approached through standard posterolateral and posteromedial portals. A 4.0-mm-diameter 30° arthroscope is used. Soft tissues around the talus are cleared with a motorized shaver and a radiofrequency device. The posterior aspects of the talus, os trigonum, and FHL tendon surrounded by the tendon sheath are visualized. The dynamic pathology of the FHL tendon is well observed on passive motion of the great toe. The prominent bone fragment of the talus is removed and the tendon sheath is cut with a retrograde knife and a motorized shaver from the superior border down to the entrance of the fibro-osseous tunnel. Arthroscopic release of the FHL tendon sheath is a useful and easy method to directly approach the dynamic pathology of FHL tenosynovitis in female ballet dancers.

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. In the present study, we analyzed the therapeutic effects of hyaluronan injections for tendinopathy in an animal model. METHODS: We made the tendinopathy rat model using a rodent treadmill machine. Rats with tendinopathy were injected with HMW HA (HA group), normal saline (NS group), or nothing (control group) into the space between the patellar tendon and the fat pad bilaterally, or were injected with HMW HA into the right knees and with saline to the left knees (HA/NS group), 5 times every 4 days. To assess the pain-relieving effect of HA, the spontaneous locomotor activities at night (12 h) and weight bearing of hind paws were measured every day. Histological sections of the patellar tendon stained with hematoxylin-eosin or prepared by TdT-mediated dUTP nick end labeling were microscopically analyzed. RESULTS: The number of spontaneous locomotor activities in the HA group was significantly larger than those in NS or control groups, and in the HA group they recovered up to a healthy level. The percent weight distribution of the right hind paws was significantly increased along with the number of injections. On histologic examinations, the numbers of microtears, laminations, or apoptotic cells in the patellar tendons in the HA group were significantly lower than those in the NS or the control groups. CONCLUSIONS: The injections of HMW HA were effective for pain relief and for partial restoration of the patellar tendon in our tendinopathy rat model, and thus may become an effective therapeutic modality for the disease.

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. METHODS: Cells derived from the ACL, MCL, and PT of New Zealand white rabbits were isolated. Each cell type was cultured for up to 4 weeks after reaching confluence. Cell-matrix layers were evaluated and compared for their morphology, collagen cross-links, and gene expression levels of lysine hydroxylase 1 and 2, lysyl oxidase (LOX), tenomodulin, collagen1A1 (Col1A1), and collagen3A1 (Col3A1). RESULTS: Transmission electron microscopy photomicrographs verified that collagen fibrils were secreted from all three types of fibroblasts. A higher ratio of dihydroxylysinonorleucine/hydroxylysinonorleucine was evident in the ligament compared to the tendon, which was consistent with lysine hydroxylase 2/lysine hydroxylase 1 gene expression. The gene expression of LOX, which regulates the total amount of enzymatic cross-linking, and the gene expression levels of Col1A1 and Col3A1 were higher in the ACL matrix than in the MCL and PT matrices. CONCLUSION: ACL, MCL, and PT cells have distinct collagen maturation processes at the cellular level. In addition, the collagen maturation of ACL cells is not necessarily inferior to that of MCL and PT cells in that all three cell types have a good ability to synthesize collagen and induce collagen maturation. This bioactivity of ACL cells in terms of ligament-specific mature collagen induction can be applied to tissue-engineered ACL reconstruction or remnant preserving procedure with ACL reconstruction.

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. He did not respond to conservative treatment and thus underwent arthroscopic excision of fragments of the talar lateral process. The ankle was approached through standard medial and anterolateral portals. A 2.7-mm-diameter 30° arthroscope was used. Soft tissues around the talus were cleared with a motorized shaver, and the lateral aspect of the talar process was then visualized. The lateral process presented as an osseous overgrowth, and a loose body was impinged between the talus and the calcaneus. The osseous overgrowth was resected piece by piece with a punch, and the loose body was removed en block. The patient returned to soccer 5 weeks after the operation. This case exemplifies 2 important points: (1) This type of fracture can develop even in children and not only in snowboarders. (2) Arthroscopic excision of talar lateral process fragments can be accomplished easily, and return to sports can be achieved in a relatively short time.

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. RESULTS: Plain radiographs did not reveal the presence of lesion; however, 3D-CT and MRI scans showed a small bony fragment located between the humeral head and the glenoid of the scapula and a high-intensity area of the subscapularis tendon. He was subsequently diagnosed with incomplete joint side tear of the subscapularis tendon with a small bony fragment. Subsequently, we performed arthroscopic excision of the bony fragment and repair of the subscapularis tendon. CONCLUSIONS: This case highlighted the presence of an injury with minor trauma associated with repeated tennis strokes in a skeletally immature patient.

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. Primary cultured human chondrocytes were used for the study. The production of collagenase-1 was major in total production for three isozymes of collagenase after stimulations with any concentration of tumor necrosis factor-alpha and/or interleukin-1 at 48 and 72 h, comprising 98% or greater of the total collagenase. When the production of collagenase-1 was specifically suppressed by the transfection with duplexes of 21-nucleotide small interfering ribonucleic acid into the cells, the activity of type II collagen cleavage was linearly decreased at neutral pH after activation. The relative contribution of collagenase-1 to the primary cleavage of type II collagen was determined to be 85%-93%. These findings suggest that collagenase-1 is a major contributor to the primary cleavage of type II collagens in human cartilage and is a potential therapeutic target for osteoarthritis and rheumatoid arthritis.