B‐mode and power Doppler sonographic findings in the long bicipital tendon in ankylosing spondylitis

Objectives: The aim of this study was to assess B‐mode and power Doppler ultrasound findings of long head of biceps tendon in patients with ankylosing spondylitis (AS). Methods: Anthropometric measurements were carried out and disease activity and functional status were evaluated with BASDAI, BASFI, Dougados Functional Index (DFI) and Articular Index (DAI) in 30 patients with AS. The Shoulder Disability Questionnaire (SDQ) was performed. Pressure pain threshold (PPT) was measured on bilateral long head of biceps tendon and B‐mode and power Doppler ultrasound were carried out. Focal changes (hypoechogenic areas within the tendon), calcification of the tendon, and fluid collection inside or outside the tendon sheath at bicipital groove (peritendinous hypoechoic rim) and vascularity of the peritendinous region were assessed. A cumulative ultrasound score (CUSS) was obtained. Results: Focal changes were present in five tendons of four patients. Calcification of the tendon was present in three tendons of three patients. Biceps tendon sheath effusion (peritendinous hypoechoic rim) was observed in 10 tendons of eight patients. Thirteen tendons of eight patients had discernible flow signals, six were inside the tendon sheath (within the hypoechoic rim) and seven were outside the tendon sheath. Cumulative US score correlated significantly with DFI and ESR. There was not a significant correlation between CUSS and total PPT. Conclusion: Ultrasound examination of the long head of biceps tendon gives detailed information of the tendon and PDUS has the potential to be able to show inflammatory activity of the tendon.     

Demonstration of the reentrant circuit of verapamil-sensitive idiopathic left ventricular tachycardia: direct evidence for macroreentry as the underlying mechanism

The exact reentrant circuit of verapamil-sensitive idiopathic left ventricular tachycardia (ILVT) remains unclear. This case report demonstrates the reentrant circuit of ILVT. A 20-pole electrode catheter was placed along the left posterior fascicle during electrophysiologic study. ILVT was reproducibly induced by programmed ventricular stimulation. During the tachycardia, sequential diastolic potentials bridging the entire diastolic period were observed in the recordings from the electrodes positioned from left ventricular mid-septum to inferoapical septum. The slow conduction zone appeared to be composed of a false tendon in this patient. Entrainment of the ILVT from the right ventricular outflow tract at a different pacing cycle length revealed that a dominant conduction delay occurred at the proximal site of the slow conduction zone. Entrainment studies from several sites on the left ventricular septum confirmed that these sites where sequential electrical activity was recorded were included within the reentrant circuit. However, the left posterior fascicle itself seemed to be a bystander. This report provides the direct evidence of macroreentry as the underlying mechanism of this ILVT, adjacent to the left posterior fascicle.     

Inertial flywheel vs heavy slow resistance training among athletes with patellar tendinopathy: A randomised trial

ObjectivesTo compare the efficacy of inertial flywheel and heavy slow resistance training in reducing pain and improving function in patellar tendinopathy.DesignRandomised clinical trial.MethodsFourty two participants (1 woman, 41 men) with longstanding (>3 months) patellar tendinopathy were randomised into inertial flywheel resistance (N = 21) or heavy slow resistance (N = 21) group. Both programmes consisted of three supervised inertial flywheel or heavy slow resistance exercise sessions per week in a fitness center during 12 weeks. Primary outcome was pain and function, assessed by the Spanish Victorian Institute of Sport Assessment for Patella (VISA-P) score at 6 and 12 weeks. Secondary outcomes were activity limitation using Patient Specific Functional Scale (PSFS), health status (EuroQol-5D), patient impression of change on pain and function, adherence, adverse events, pain provocation test for the patellar tendon (numerical rating score of pain between 0 and 10), physical test, patellar tendon thickness and doppler signal on ultrasound. Secondary outcomes were taken at 0 and 12 weeks.ResultsBoth groups showed significant improvements in VISA-P scores from 0 to 12 weeks but there was not statistically significant between-group difference (P = 0.506). No adverse events or side effects occurred in any of the groups during the intervention period.ConclusionsInertial flywheel resistance three times a week during 12 weeks resulted in similar pain and function benefit at 12 weeks compared with the heavy slow resistance training among people with patellar tendinopathy. Flywheel training is another exercise option for managing people with patellar tendinopathy.ClinicalTrials.gov RegistryNCT03917849.     

Rotator cuff strength is not augmented by blood flow restriction training

ObjectiveBlood flow restriction (BFR) training utilizes a tourniquet applied to the upper or lower extremities (UE or LE) to occlude blood flow while exercising. BFR training may help augment strength in muscles that are proximal to BFR cuff application. However, prior studies have failed to demonstrate augmented strength gains in the rotator cuff when the tourniquet is applied to the UE. The purpose of this study was to evaluate if a protocol consisting of LE exercises, performed with BFR, followed by rotator cuff exercises was superior in augmenting strength, and cross-sectional area (CSA) of the rectus femoris, in untrained subjects when compared to a non-BFR training group.DesignRandomized controlled trial.SettingUniversity.ParticipantsThirty-five subjects (mean age 25.8 ± 1.6 y) randomized to a BFR or non-BFR group.Main outcome measuresMuscular strength measured via hand held dynamometer and the CSA of the dominant rectus femoris was measured by diagnostic ultrasound.ResultsBoth groups experienced significant gains in LE and rotator cuff strength. Strength increased in the BFR group by 11.6% for the supraspinatus, 34.1% for shoulder ER, 23.4% for the quadriceps, and 17.1% for the hamstrings. Strength increased in the non-BFR group by 7.3% for the supraspinatus, 20% for shoulder ER, 12.8% for the quadriceps, and 10.7% for the hamstrings. However, there were no differences in strength gains between groups. Neither group experienced a significant increase in CSA for the rectus femoris.ConclusionThe BFR protocol used in this study did not augment strength for the rotator cuff in subjects who also performed LE exercises under occlusion.     

Can Achilles and patellar tendon structures predict musculoskeletal injuries in combat soldiers?

Aiming to investigate whether Achilles tendon (AT) structure and patellar tendon (PT) structure are risk factors for musculoskeletal injuries in combat soldiers, 168 participants were recruited from an infantry commander's course. The AT and PT were examined pre‐course using UTC to capture the structure of four echo‐type fibers (I–IV). All injuries were assessed by military physicians pre‐course and throughout the 14‐week course. Soldiers who were injured during the course had a significantly higher pre‐course prevalence of AT and PT echo‐type III and echo‐type IV compared to soldiers that were not injured during the course. Variables that were found to be associated with injured/non‐injured participants were echo‐type III + IV of the PT (OR = 1.44, 95% CI = 1.24‐1.68) and echo‐type III of the AT (OR = 1.69, 95% CI = 1.35‐2.12). ROC analyses showed that the best model, exhibiting both high sensitivity and low specificity, was that participants with PT echo‐type III + IV > 10% or AT echo‐type III >8.5% had the highest risk of being injured during the course. In conclusions, the tendon structure at the beginning of high‐intensity activity or physical training program might be a risk factor for subsequent injury during the course. Soldiers and high‐level athletes should be aware of the cutoff points for fiber types in tendon structure that might put them at high risk for future injury. At‐risk soldiers/athletes should be provided with an intervention program before they start their training program, with the aim of improving the tendon structure and preventing subsequent injury.     

Effective and selective stretching of the medial head of the gastrocnemius

Muscle injury frequently occurs in the medial head of the gastrocnemius (MG), and stretching is used for treatment. However, there are no studies based on anatomical considerations and biomechanics. This study therefore examined the macroscopic anatomical structure of the triceps surae muscle to design an effective and selective MG stretching method, before quantitatively verifying that method by ultrasonography. The macroscopic anatomy was analyzed in 16 Japanese cadavers (25 legs). Based on the anatomical findings and the arrangement of fascicles in the MG, we concluded that ankle inversion might be advantageous for selective stretching of the tendon fiber bundles into which the MG inserts. We devised a method in which the limb was initially positioned with the knee joint in extension and the ankle joint in plantar flexion. Then, the ankle was dorsiflexed and inverted. The proposed method was compared with standard stretching and verified by ultrasonography in eight healthy adult males. This method effectively and selectively stretched the MG, producing a significantly decreased pennation angle and increased muscle fiber length. This method may be beneficial for preventing future injuries and may enhance the effect of therapy on the MG.     

一例纯种雌马驹屈腱挛缩病的诊疗

本文结合临床所遇一雌性马驹屈腱挛缩病例,对其发病情况、诊断要点、中西药治疗方法和预防措施进行了论述,以供同行在临床实践中参考。     

Effects of trypsinization and mineralization on intrasynovial tendon allograft healing to bone

The purpose of the current study was to develop a novel technology to enhance tendon‐to‐bone interface healing by trypsinizing and mineralizing (TM) an intrasynovial tendon allograft in a rabbit bone tunnel model. Eight rabbit flexor digitorum profundus (FDP) tendons were used to optimize the trypsinization process. An additional 24 FDP tendons were stratified into control and TM groups; in each group, 4 tendons were used for in vitro evaluation of TM and 8 were transplanted into proximal tibial bone tunnels in rabbits. The samples were evaluated histologically and with mechanical testing at postoperative week 8. Maximum failure strength and linear stiffness were not significantly different between the control and TM tendons. A thin fibrous band of scar tissue formed at the graft‐to‐bone interface in the control group. However, only the TM group showed obvious new bone formation inside the tendon graft and a visible fibrocartilage layer at the bone tunnel entrance. This study is the first to explore effects of TM on the intrasynovial allograft healing to a bone tunnel. TM showed beneficial effects on chondrogenesis, osteogenesis, and integration of the intrasynovial tendon graft, but mechanical strength was the same as the control tendons in this short‐term in vivo study. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:468–474, 2015.     

Parathyroid hormone 1–34 enhances extracellular matrix deposition and organization during flexor tendon repair

Parathyroid hormone (PTH) 1–34 is known to enhance fracture healing. Tendon repair is analogous to bone healing in its dependence on the proliferation and differentiation of mesenchymal stem cells, matrix formation, and tissue remodeling.^1,2,3 We hypothesized that PTH 1–34 enhances tendon healing in a flexor digitorum longus (FDL) tendon repair model. C57Bl/6J mice were treated with either intraperitoneal PTH 1–34 or vehicle‐control (PBS). Tendons were harvested at 3–28 days for histology, gene expression, and biomechanical testing. The metatarsophalangeal joint range of motion was reduced 1.5–2‐fold in PTH 1–34 mice compared to control mice. The gliding coefficient, a measure of adhesion formation, was 2–3.5‐fold higher in PTH 1–34 mice. At 14 days post‐repair, the tensile strength was twofold higher in PTH 1–34 specimens, but at 28 days there were no differences. PTH 1–34 mice had increased fibrous tissue deposition that correlated with elevated expression of collagens and fibronectin as seen on quantitative PCR. PTH 1–34 accelerated the deposition of reparative tissue but increased adhesion formation. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:17–24, 2015.     

Effect of highly purified capsaicin on articular cartilage and rotator cuff tendon healing: An in vivo rabbit study

Highly purified capsaicin has emerged as a promising injectable compound capable of providing sustained pain relief following a single localized treatment during orthopedic surgical procedures. To further assess its reliability for clinical use, the potential effect of highly purified capsaicin on articular cartilage metabolism as well as tendon structure and function warrants clarification. In the current study, rabbits received unilateral supraspinatus transection and repair with a single 1 ml injection of capsaicin (R + C), PEG‐only placebo (R + P), or saline (R + S) into the glenohumeral joint (GHJ). An additional group received 1 ml capsaicin onto an intact rotator cuff (I + C). At 18 weeks post‐op, cartilage proteoglycan (PG) synthesis and content as well as cell viability were similar (p > 0.05) across treatment groups. Biomechanical testing revealed no differences (p > 0.05) among tendon repair treatment groups. Similarly, histologic features of both cartilage and repaired tendons showed minimal differences across groups. Hence, in this rabbit model, a single injection of highly purified capsaicin into the GHJ does not induce a deleterious response with regard to cartilage matrix metabolism and cell viability, or rotator cuff healing. These data provide further evidence supporting the use of injectable, highly purified capsaicin as a safe alternative for management of postoperative pain following GHJ surgery. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1854–1860, 2015.