Richard Newsham-West

Chronic tendinopathy: effectiveness of eccentric exercise

Objectives: To determine the effectiveness of eccentric exercise (EE) programmes in the treatment of common tendinopathies. Data sources: Relevant randomised controlled trials (RCTs) were sourced using the OVID website databases: MEDLINE (1966–Jan 2006), CINAHL (1982–Jan 2006), AMED (1985–Jan 2006), EMBASE (1988–Jan 2006), and all EBM reviews – Cochrane DSR, ACP Journal Club, DARE, and CCTR (Jan 2006). The Physiotherapy Evidence Database (PEDro) was also searched using the keyword: eccentric. Review methods: The PEDro and van Tulder scales were employed to assess methodological quality. Levels of evidence were then obtained according to predefined thresholds: Strong–consistent findings among multiple high-quality RCTs. Moderate–consistent findings among multiple low-quality RCTs and/or clinically controlled trials (CCTs) and/or one high-quality RCT. Limited–one low-quality RCT and/or CCT. Conflicting–inconsistent findings among multiple trials (RCTs and/or CCTs). No evidence–no RCTs or CCTs. Results: Twenty relevant studies were sourced, 11 of which met the inclusion criteria. These included studies of Achilles tendinopathy (AT), patella tendinopathy (PT) and tendinopathy of the common wrist extensor tendon of the lateral elbow (LET). Limited levels of evidence exist to suggest that EE has a positive effect on clinical outcomes such as pain, function and patient satisfaction/return to work when compared to various control interventions such as concentric exercise (CE), stretching, splinting, frictions and ultrasound. Levels of evidence were found to be variable across the tendinopathies investigated. Conclusions: This review demonstrates the dearth of high-quality research in support of the clinical effectiveness of EE over other treatments in the management of tendinopathies. Further adequately powered studies that include appropriate randomisation procedures, standardised outcome measures and long-term follow-up are required.

Examining injury risk and pain perception in runners using minimalist footwear

Background This study examines the effect of progressive increases in footwear minimalism on injury incidence and pain perception in recreational runners. Methods One hundred and three runners with neutral or mild pronation were randomly assigned a neutral (Nike Pegasus 28), partial minimalist (Nike Free 3.0 V2) or full minimalist shoe (Vibram 5-Finger Bikila). Runners underwent baseline testing to record training and injury history, as well as selected anthropometric measurements, before starting a 12-week training programme in preparation for a 10 km event. Outcome measures included number of injury events, Foot and Ankle Disability (FADI) scores and visual analogue scale pain rating scales for regional and overall pain with running. Results 99 runners were included in final analysis with 23 injuries reported; the neutral shoe reporting the fewest injuries (4) and the partial minimalist shoe (12) the most. The partial minimalist shoe reported a significantly higher rate of injury incidence throughout the 12-week period. Runners in the full minimalist group reported greater shin and calf pain. Conclusions Running in minimalist footwear appears to increase the likelihood of experiencing an injury, with full minimalist designs specifically increasing pain at the shin and calf. Clinicians should exercise caution when recommending minimalist footwear to runners otherwise new to this footwear category who are preparing for a 10 km event.

Effects of running on human Achilles tendon length–tension properties in the free and gastrocnemius components

SUMMARY The elastic properties of the human Achilles tendon are important for locomotion; however, in vitro tests suggest that repeated cyclic contractions lead to tendon fatigue – an increase in length in response to stress applied. In vivo experiments have not, however, demonstrated mechanical fatigue in the Achilles tendon, possibly due to the limitations of using two-dimensional ultrasound imaging to assess tendon strain. This study used freehand three-dimensional ultrasound (3DUS) to determine whether the free Achilles tendon (calcaneus to soleus) or the gastrocnemius tendon (calcaneus to gastrocnemius) demonstrated tendon fatigue after running exercise. Participants (N=9) underwent 3DUS scans of the Achilles tendon during isometric contractions at four ankle torque levels (passive, and 14, 42 and 70 N m) before and after a 5 km run at a self-selected pace (10–14 km h−1). Running had a significant main effect on the length of the free Achilles tendon (P<0.01) with a small increase in length across the torque range. However, the mean lengthening effect was small (<1%) and was not accompanied by a change in free tendon stiffness. There was no significant change in the length of the gastrocnemius tendon or the free tendon cross-sectional area. While the free tendon was shown to lengthen, the lack of change in stiffness suggests the tendon exhibited mechanical creep rather than fatigue. These effects were much smaller than those predicted from in vitro experiments, possibly due to the different loading profile encountered and the ability of the tendon to repair in vivo.

Immediate effect of exercise on Achilles tendon properties: systematic review

INTRODUCTION Understanding the mechanical and morphological adaptation of the Achilles tendon (AT) in response to acute exercise could have important implications for athletic performance, injury prevention, and rehabilitation. The purpose of this study was to conduct a systematic review and critical evaluation of the literature to determine the immediate effect of a single bout of exercise on the mechanical and morphological properties of the AT in vivo. METHODS Five electronic research databases were systematically searched for intervention-based studies reporting mechanical and morphological properties of the AT after a single bout of exercise. RESULTS Searches revealed 3292 possible articles; 21 met the inclusion criteria. There is evidence that maximal isometric contractions and prolonged static stretching (>5 min) of the triceps surae complex cause an immediate decrease in AT stiffness, whereas prolonged running and hopping have minimal effect. Limited but consistent evidence exists, indicating that AT hysteresis is reduced after prolonged static stretching. Consistent evidence supports a reduction in free AT diameter (anterior-posterior) after dynamic ankle exercise, and this change appears most pronounced in the healthy tendon and after eccentric exercise. CONCLUSIONS The mechanical and morphological properties of the AT in vivo are affected by acute exercise in a mode- and dose-dependent manner. Transient changes in AT stiffness, hysteresis, and diameter after unaccustomed exercise modes and doses may expose the tendon to increased risk of strain injury and impact on the mechanical function of the triceps surae muscle-tendon unit.

Raising the standards of the calf-raise test: A systematic review

The calf-raise test is used by clinicians and researchers in sports medicine to assess properties of the calf muscle-tendon unit. The test generally involves repetitive concentric-eccentric muscle action of the plantar-flexors in unipedal stance and is quantified by the number of raises performed. Although the calf-raise test appears to have acceptable reliability and face validity, and is commonly used for medical assessment and rehabilitation of injuries, no universally acceptable test parameters have been published to date. A systematic review of the existing literature was conducted to investigate the consistency as well as universal acceptance of the evaluation purposes, test parameters, outcome measurements and psychometric properties of the calf-raise test. Nine electronic databases were searched during the period May 30th to September 21st 2008. Forty-nine articles met the inclusion criteria and were quality assessed. Information on study characteristics and calf-raise test parameters, as well as quantitative data, were extracted; tabulated; and statistically analysed. The average quality score of the reviewed articles was 70.4+/-12.2% (range 44-90%). Articles provided various test parameters; however, a consensus was not ascertained. Key testing parameters varied, were often unstated, and few studies reported reliability or validity values, including sensitivity and specificity. No definitive normative values could be established and the utility of the test in subjects with pathologies remained unclear. Although adapted for use in several disciplines and traditionally recommended for clinical assessment, there is no uniform description of the calf-raise test in the literature. Further investigation is recommended to ensure consistent use and interpretation of the test by researchers and clinicians.

Three-dimensional deformation and transverse rotation of the human free Achilles tendon in vivo during isometric plantarflexion contraction.

Freehand three-dimensional ultrasound (3DUS) was used to investigate longitudinal and biaxial transverse deformation and rotation of the free Achilles tendon in vivo during a voluntary submaximal isometric muscle contraction. Participants (n = 8) were scanned at rest and during a 70% maximal voluntary isometric contraction (MVIC) of the plantarflexors. Ultrasound images were manually digitized to render a 3D reconstruction of the free Achilles tendon for the computation of tendon length, volume, cross-sectional area (CSA), mediolateral diameter (MLD), anteroposterior diameter (APD), and transverse rotation. Tendon longitudinal and transverse (CSA, APD, and MLD) deformation and strain at 70% MVIC were calculated relative to the resting condition. There was a significant main effect of contraction on tendon length and mean CSA, MLD, and APD (P < 0.05), but no effect on tendon volume (P = 0.70). Group mean transverse strains for CSA, MLD, and APD averaged over the length of the tendon were -5.5%, -8.7% and 8.7%, respectively. Peak CSA, MLD, and APD transverse strains all occurred between 40% and 60% of tendon length. Transverse rotation of the free tendon was negligible at rest but increased under load, becoming externally rotated relative to the calcaneal insertion. The relationship between longitudinal and transverse strains of the free Achilles tendon during muscle-induced elongation may be indicative of interfascicle reorganization. The finding that transverse rotation and strain peaked in midportion of the free Achilles tendon may have important implications for tendon injury mechanisms and estimation of tendon stress in vivo.

Scientific bases and clinical utilisation of the calf-raise test.

BACKGROUND Athletes commonly sustain injuries to the triceps surae muscle-tendon unit. The calf-raise test (CRT) is frequently employed in sports medicine for the detection and monitoring of such injuries. However, despite being widely-used, a recent systematic review found no universal consensus relating to the tests purpose, parameters, and standard protocols. OBJECTIVES The purpose of this paper is to provide a clinical perspective on the anatomo-physiological bases underpinning the CRT and to discuss the utilisation of the test in relation to the structure and function of the triceps surae muscle-tendon unit. DESIGN Structured narrative review. METHODS Nine electronic databases were searched using keywords and MESH headings related to the CRT and the triceps surae muscle-tendon unit anatomy and physiology. A hand-search of reference lists and relevant journals and textbooks complemented the electronic search. SUMMARY There is evidence supporting the clinical use of the CRT to assess soleus and gastrocnemius, their shared aponeurosis, the Achilles tendon, and the combined triceps surae muscle-tendon unit. However, employing the same clinical test to assess all these structures and their associated functions remains challenging. CONCLUSIONS Further refinement of the CRT for the triceps surae muscle-tendon unit is needed. This is vital to support best practice utilisation, standardisation, and interpretation of the CRT in sports medicine.

Changes in Achilles tendon mechanical properties following eccentric heel drop exercise are specific to the free tendon

Mechanical loading of the Achilles tendon during isolated eccentric contractions could induce immediate and region‐dependent changes in mechanical properties. Three‐dimensional ultrasound was used to examine the immediate effect of isolated eccentric exercise on the mechanical properties of the distal (free tendon) and proximal (gastrocnemii) regions of the Achilles tendon. Participants (n = 14) underwent two testing sessions in which tendon measurements were made at rest and during a 30% and 70% isometric plantar flexion contractions immediately before and after either: (a) 3 × 15 eccentric heel drops or (b) 10‐min rest. There was a significant time‐by‐session interaction for free tendon length and strain for all loading conditions (P < 0.05). Pairwise comparisons revealed a significant increase in free tendon length and strain at all contraction intensities after eccentric exercise (P < 0.05). There was no significant time‐by‐session interaction for the gastrocnemii (medial or lateral) aponeurosis or tendon for any of the measured parameters. Immediate changes in Achilles tendon mechanical properties were specific to the free tendon and consistent with changes due to mechanical creep. These findings suggest that the mechanical properties of the free tendon may be more vulnerable to change with exercise compared with the gastrocnemii aponeurosis or tendon.

Comparison of a Physiotherapy Program versus Dexamethasone Injections for Plantar Fasciopathy in Prolonged Standing Workers: A Randomized Clinical Trial

Objective:To investigate the effectiveness of a physiotherapy-based exercise program versus dexamethasone injection for chronic plantar fasciopathy in workers standing for prolonged periods of time. Design:A parallel group nonblinded randomized controlled trial with 12-week follow-up. Setting:An outpatient sports medicine clinic in Vancouver, British Columbia, Canada. Participants:Fifty-six workers required to stand for greater than 5 h/d with chronic plantar fasciopathy took part. Diagnosis from a physiotherapist must include signs of structural changes to the plantar fascia seen on ultrasound. Interventions:The PHYSIO group included 7 physiotherapy-led exercises performed daily over a 12-week period. The INJECTION group received 1 palpation-guided dexamethasone injection followed by a daily routine of calf stretching. Main Outcome Measures:The Foot and Ankle Disability Index (FADI) scores 12-weeks postintervention and ultrasound-based measures of ligament appearance. Results:At follow-up, both groups reported significant improvements in FADI and visual analog scales for pain at work and with activities of daily living at 6 and 12 weeks compared with baseline scores (P < 0.001). There were no significant between-group differences. There were no significant changes to plantar fascia thickness reported at the 6- and 12-week follow-up point. Both the number of cases with focal anechoic areas and the size of these anechoic areas improved significantly in the PHYSIO (P = 0.003) and INJECTION (P < 0.001) groups at 12-week follow-up. Conclusions:Workers standing for prolonged periods experienced the same short-term therapeutic effectiveness with a physiotherapy-led exercise program compared with an injection of corticosteroid with stretching.

Pre-race health status and medical events during the 2005 World Adventure Racing Championships.

Adventure racing is a wilderness multisport endurance event with the potential for significant injury and illness; however specific contributing factors have not been extensively studied. A prospective cross-sectional study was conducted that collected data during the 2005 Adventure Racing World Championship on pre-, in- and post-race injury and illness and determined pre-race training volumes and health profiles in 184 athletes (46 teams of 4 athletes). In the 6 months prior to the event, 79.9% of athletes reported an injury or illness. Fifty-nine cases of injury or illness were recorded during the race; representing an overall rate of 2.5 injuries per 1000 race-hours and 1.0 illness per 1000 race-hours. This incidence could be considered low compared to some sports, but the rate is tempered by the time on course exposure of 16,774 race-hours. Respiratory conditions were the single-most common condition resulting in race withdrawal. There was a moderate, but not statistically significantly, association (OR=4.61, p=0.083, 95% CI 0.82-26.08) between pre-race illness and in-race illness. Forty-four (95%) teams responded to a post-race questionnaire with 30% of the athletes reporting a new injury and 12% reporting a new illness in the week following the race. Understanding contributing factors to injury and illness during adventure racing will aid implementation of race medical coverage, preventative strategies and increase participation and performance.