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Background: Anterior cruciate ligament (ACL) injuries often occur when an athlete experiences an unexpected disruption, or perturbation, during sports. ACL injury rates may also be influenced by the menstrual cycle. Purpose: To determine whether training adaptations to knee control and muscle activity during a perturbed single-leg squatting (SLS) task depend on menstrual cycle phase in female athletes. Study Design: Controlled laboratory study. Methods: A total of 21 healthy female collegiate athletes (current or former [<3 years]) who competed in 9 different sports performed an SLS task in which they attempted to match their knee position (user signal) to a target signal. The protocol consisted of a 9-condition pretest, 5 sets of 3 training trials, and a 9-condition posttest. One perturbation was delivered in each condition by altering the resistance of the device. Sagittal knee control (absolute error between the target signal and user signal) was assessed using a potentiometer. Muscle activity during perturbed squat cycles was normalized to maximal activation and to corresponding muscle activity during unperturbed squat cycles (%unperturbed) within the same test condition. Athletes performed the protocol during a distinct menstrual cycle phase (early follicular [EF], late follicular [LF], midluteal [ML]). Two-way mixed analysis of variance was used to determine the effects of the menstrual cycle and training on knee control and muscle activity during task performance. Venous blood was collected for hormonal analysis, and a series of health questionnaires and anthropometric measures were also assessed to determine differences among the menstrual cycle groups. Results: After training, athletes demonstrated better knee control during the perturbed squat cycles (lower absolute error, P <.001) and greater soleus feedback responses to the perturbation (%unperturbed, P =.035). Better knee control was demonstrated in the ML phase versus the EF phase during unperturbed and perturbed squat cycles (P <.039 for both). Quadriceps activation was greater in the ML phase compared with the EF and LF phases, both immediately before and after the perturbation (P <.001 for all). Conclusion: Athletes learned to improve knee control during the perturbed performance regardless of menstrual cycle phase. The best knee control and greatest quadriceps activation during the perturbed squatting task was found in the ML phase. Clinical Relevance: These findings may correspond to a lower incidence of ACL injury in the luteal phase and alterations in exercise performance across the menstrual cycle. [ABSTRACT FROM AUTHOR]

The suggestion that bidirectional flow is a normal feature seen in venous perforators of the lower leg has been a longstanding debate. Newer published evidence has changed the perspective on normal perforator flow and is presented here to resolve the misunderstandings and different viewpoints previously held. [ABSTRACT FROM AUTHOR]

Background: A number of studies have reported that calf muscle atrophy is a common long-term problem after Achilles tendon repair; however, there is still a lack of data concerning early postoperative morphological changes in the calf muscle after surgery. Purpose: To investigate changes over time in calf muscle volume and fatty degeneration during 1 year after Achilles tendon repair. Study Design: Cohort study; Level of evidence, 2. Methods: A prospective 1-year serial magnetic resonance imaging study was carried out with 20 patients who underwent tendon repair for unilateral acute Achilles tendon rupture. The magnetic resonance imaging assessment in addition to clinical and functional evaluations was performed at 1, 3, 6, and 12 months after surgery. The muscle volume of the medial and lateral gastrocnemius, soleus, and flexor hallucis longus (FHL) and fatty degeneration of the medial and lateral gastrocnemius and soleus were measured for the calf muscles, and the relative volume and fatty degeneration changes in the affected leg compared with the healthy contralateral leg were calculated as a percentage ([injured/healthy control] × 100) to assess structural changes over time. Results: Muscle volumes of the medial gastrocnemius, lateral gastrocnemius, soleus, and FHL were 92.3%, 92.8%, 84.6%, and 95.9% at 12 months after surgery, respectively. Medial and lateral gastrocnemius and FHL muscle volumes improved over time and recovered to almost equal to that of the healthy side at 12 months after surgery. The soleus muscle volume did not recover significantly over time and was statistically significantly smaller than that of the healthy side at 12 months (P =.029). Fatty degeneration rates of the medial gastrocnemius, lateral gastrocnemius, and soleus were 118.2%, 113.9% and 121.1% at 12 months after surgery, respectively. Fatty degeneration of the medial and lateral gastrocnemius did not change significantly, but there was a statistically significant increase in fatty degeneration of the soleus over time (P <.001). Conclusion: Within the triceps surae muscle, the soleus was the most negatively affected by injury and repair for both muscle volume and fatty degeneration. Postoperative management to recover the soleus muscle function before a return to sporting activities should be considered in the future. [ABSTRACT FROM AUTHOR]

Background: Previous studies have examined the transcriptomes and mechanical properties of whole tendons in different regions of the body. However, less is known about these characteristics within a single tendon. Purpose: To develop a regional transcriptomic atlas and evaluate the region-specific mechanical properties of Achilles tendons. Study Design: Descriptive laboratory study. Methods: Achilles tendons from 2-month-old male Sprague Dawley rats were used. Tendons were isolated and divided into proximal, middle, and distal thirds for RNA sequencing (n = 5). For mechanical testing, the Achilles muscle-tendon-calcaneus unit was mounted in a custom-designed materials testing system with the unit clamped over the musculotendinous junction (MTJ) and the calcaneus secured at 90° of dorsiflexion (n = 9). Tendons were stretched to 20 N at a constant speed of 0.0167 mm/s. Cross-sectional area, strain, stress, and Young modulus were determined in each tendon region. Results: An open-access, interactive transcriptional atlas was generated that revealed distinct gene expression signatures in each tendon region. The proximal and distal regions had the largest differences in gene expression, with 2596 genes significantly differentially regulated at least 1.5-fold (q <.01). The proximal tendon displayed increased expression of genes resembling a tendon phenotype and increased expression of nerve cell markers. The distal region displayed increases in genes involved in extracellular matrix synthesis and remodeling, immune cell regulation, and a phenotype similar to cartilage and bone. There was a 3.72-fold increase in Young modulus from the proximal to middle region (P <.01) and an additional 1.34-fold increase from the middle to distal region (P =.027). Conclusion: Within a single tendon, there are region-specific transcriptomic signatures and mechanical properties, and there is likely a gradient in the biological and functional phenotype from the proximal origin at the MTJ to the distal insertion at the enthesis. Clinical Relevance: These findings improve our understanding of the underlying biological heterogeneity of tendon tissue and will help inform the future targeted use of regenerative medicine and tissue engineering strategies for patients with tendon disorders. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of whole body vibration on chronic ankle instability-associated sensorimotor deficits in balance, strength, joint position sense and muscle activity. Data sources: Electronic databases including Cochrane Library, PubMed, Embase, Web of Science, EBSCO, China National Knowledge Infrastructure and WanFang were searched from database inception up to 31 March 2022. Methods: The risk of bias and methodological quality of included studies were assessed using the Cochrane tool and Physiotherapy Evidence Database (PEDro) scale respectively. Standardized mean difference (SMD) and mean differences (MD) with 95% confidence interval (CI) were calculated using the RevMan 5.3 software. Meta-regression was conducted with Stata 16. Results: Eight studies, with 315 subjects were eventually included in this review with an average PEDro score of 6.1/10. Significant effects of whole body vibration on balance (SMD = 0.61, 95% CI: 0.12 to 1.09, P = 0.01), and on the posterolateral direction (MD = 5.52, 95% CI: 1.02 to 10.01, P = 0.02) and medial direction (MD = 3.90, 95% CI: 0.87 to 6.94, P = 0.01) of the star excursion balance test were found. Whole body vibration significantly improved the peak torque (SMD = 0.36, 95% CI: 0.04 to 0.69, P = 0.03), joint position sense (SMD = 0.60, 95% CI: 0.10 to 1.11, P = 0.02), and muscle activity in tibialis anterior (SMD = 0.46, 95% CI: 0.04 to 0.88, P = 0.03) and gastrocnemius (SMD = 0.68, 95% CI: 0.14 to 1.23, P = 0.01). Conclusions: The current evidence supports the use of whole body vibration to improve sensorimotor deficits involving balance, strength, joint position sense, and muscle activity in people with chronic ankle instability. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the changes in pain pressure threshold (PPT) and active cervical range of motion (ACROM) after the application of superficial dry needling (DN) or deep DN in myofascial trigger point (MTrP) 1 of the upper trapezius versus a simulated DN technique in the gastrocnemius muscle (control group). Design: Double-blind, randomized controlled trial with 7-day follow-up. Participants: Asymptomatic volunteers (n = 180; 76 men, 104 women) with a latent MTrP 1 in the upper trapezius were randomly divided into three groups: G1, receiving superficial DN in the upper trapezius; G2, receiving deep DN in the upper trapezius; and G3, control group, receiving simulated DN technique in the gastrocnemius muscle. Main outcome measures: While sitting in a chair, each subject underwent measurements of PPT and ACROM (ipsilateral and contralateral side flexion and rotation, flexion and extension) preintervention, (immediately) postintervention, and at 24 h, 72 h and 7 days. Results: Superficial and deep DN produced an increase in PPT at 7 days with respect to preintervention levels. Furthermore, superficial and deep DN produced a decrease in cervical flexion at 24 h and an increase in ipsilateral rotation until 72 h, increasing to 7 days in the case of deep DN. On the contrary, superficial DN produced an increase in ipsilateral and contralateral side flexion after intervention, unlike deep DN that produced a decrease at 24 h. Furthermore, superficial DN produced an increase in contralateral rotation at 24 h and deep DN decreased extension at 72 h. Conclusion: A single intervention of superficial or deep DN did not produce statistically significant changes in PPT or goniometry measurements. Trial registration number: NCT03719352 (ClinicalTrials.gov) [ABSTRACT FROM AUTHOR]

This randomized controlled trial explored the effects of a Ving Tsun (VT) Chinese martial art training program on reactive standing balance performance, postural muscle reflex contraction latency, leg muscle performance, balance confidence and falls in community-dwelling older adults. We randomly assigned 33 healthy older adults to either a VT group (mean age = 67.5 years) or a control group (mean age = 72.1 years). The VT group received two 1-hour VT training sessions per week for three months (24 sessions). Primary outcome measures collected before and after the intervention period were electromyographic muscle activation onset latencies of the hamstring and gastrocnemius and the center of pressure path, length and movement velocity in standing (reactive balance performance). Secondary outcome measures included isometric peak force and time to isometric peak force of the knee extensors and flexors, the Activities-Specific Balance Confidence Scale score, and fall history. Results revealed that the mean gastrocnemius muscle activation onset latency was significantly longer (22.53 ms) in the VT group after the intervention. The peak force of the knee flexors significantly increased (by 1.58 kg) in the control group over time but not in the VT group. The time to reach peak force in the knee flexors was significantly longer (by 0.51 s) in the control group (but not the VT group) at posttest compared with the pretest value. No other significant group, time, or group-by-time interaction effects were noted. We discussed possible reasons for the failure of three months of martial art training to benefit fall risks among these older adults. [ABSTRACT FROM AUTHOR]

This study evaluated the relationships between trait stress, Hoffman reflex, and performance among 36 healthy amateur male athletes. We first obtained a trait stress questionnaire from participants and then assigned them to high- and lowstress groups. We next recorded Hoffman reflex data from the soleus and lateral gastrocnemius muscles and then examined their athletic performance on testing protocols separated by a 72-hour washout period. Performance testing utilized vertical jump height, 20 -m sprint time, and standing stork tests. There were significant correlations between (a) the standing stork test, vertical jump height, and trait stress and (b) Hmax/Mmax ratios, threshold intensity (Hth), the intensity of the Hmax, and the intensity of the Hlast. Hth, the intensity of Hmax, and the intensity of Hlast were significantly higher among the low-stress compared with the high-stress participant groups (p<.05), despite participants' similar training history. We suggest that selfperceived psychological stress affects performance through neural adaptation. [ABSTRACT FROM AUTHOR]

Background The tip toe manoeuvre has been promoted as the gold standard plethysmography test for measuring calf muscle pump function. The aim was to compare the tip toe manoeuvre, dorsiflexion manoeuvre and a body weight transfer manoeuvre using the ejection fraction of air-plethysmography and evaluate which has the best pumping effect. Methods Sixty-six archived tracings on 22 legs were retrieved from an air-plethysmography workshop and analysed. Pumping performance was measured using the calf volume reduction after each manoeuvre. Results Expressed as median [inter-quartile range], body weight transfer manoeuvres resulted in a significantly greater ejection fraction (%) than tip toe manoeuvres at 59.7 [53.5–63.9] versus 42.6 [30.5–52.6], P < 0.0005 (Wilcoxon). There was no significant difference in the ejection fraction between the tip toe manoeuvre versus dorsiflexion manoeuvre, P = 0.615. The repeatability (confidence interval: 95%) of 66 ejection fraction tests was excellent: tip toe manoeuvre (±1.2), dorsiflexion manoeuvre (±1.3) and body weight transfer manoeuvre (±1.6). Conclusion The body weight transfer manoeuvre appears to be a better method of measuring the full potential of the calf muscle pump with a 40.1% relative increase in the ejection fraction compared to a tip toe manoeuvre. Exercises which involve body weight transfers from one leg to the other may be more important in optimizing calf muscle pump function than ankle movement exercises. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to observe the change of the ankle joint range of motion, the muscle strength values measured with an isokinetic dynamometer, pain scores, quality of life scale, and venous return time in chronic venous insufficiency diagnosed patients by prospective follow-up after 12-week exercise program including isokinetic exercises. Methods The patient group of this study comprised 27 patients (23 female, 4 male) who were diagnosed with chronic venous insufficiency. An exercise program including isokinetic exercise for the calf muscle was given to patients three days per week for 12 weeks. At the end of 12 weeks, five of the patients left the study due to inadequate compliance with the exercise program. As a result, control data of 22 patients were included. Ankle joint range of active motion, isokinetic muscle strength, pain, quality of life, and photoplethysmography measurements were assessed before starting and after the exercise program. Results Evaluating changes of the starting and control data depending on time showed that all isokinetic muscle strength measurement parameters, range of motion, and overall quality of life values of patients improved. Venous return time values have also increased significantly (p < 0.05). Conclusion In conclusion, increase in muscle strength has been provided with exercise therapy in patients with chronic venous insufficiency. It has been determined that the increase in muscle strength affected the venous pump and this ensured improvement in venous function and range of motion of the ankle. In addition, it has been detected that pain reduced and quality of life improved after the exercise program. [ABSTRACT FROM AUTHOR]

Background: Optimizing calf muscle performance seems to play an important role in minimizing impairments and symptoms after an Achilles tendon rupture (ATR). The literature lacks long-term follow-up studies after ATR that describe calf muscle performance over time. Purpose: The primary aim was to evaluate calf muscle performance and patient-reported outcomes at a mean of 7 years after ATR in patients included in a prospective, randomized controlled trial. A secondary aim was to evaluate whether improvement in calf muscle performance continued after the 2-year follow-up. Study Design: Cohort study; Level of evidence, 2. Methods: Sixty-six subjects (13 women, 53 men) with a mean age of 50 years (SD, 8.5 years) were evaluated at a mean of 7 years (SD, 1 year) years after their ATR. Thirty-four subjects had surgical treatment and 32 had nonsurgical treatment. Patient-reported outcomes were evaluated with Achilles tendon Total Rupture Score (ATRS) and Physical Activity Scale (PAS). Calf muscle performance was evaluated with single-leg standing heel-rise test, concentric strength power heel-rise test, and single-legged hop for distance. Limb Symmetry Index (LSI = injured side/healthy side × 100) was calculated for side-to-side differences. Results: Seven years after ATR, the injured side showed decreased values in all calf muscle performance tests (P < .001-.012). Significant improvement in calf muscle performance did not continue after the 2-year follow-up. Heel-rise height increased significantly (P = .002) between the 1-year (10.8 cm) and the 7-year (11.5 cm) follow-up assessments. The median ATRS was 96 (of a possible score of 100) and the median PAS was 4 (of a possible score of 6), indicating minor patient-reported symptoms and fairly high physical activity. No significant differences were found in calf muscle performance or patient-reported outcomes between the treatment groups except for the LSI for heel-rise repetitions. Conclusion: Continued deficits in calf muscle endurance and strength remained 7 years after ATR. No continued improvement in calf muscle performance occurred after the 2-year follow-up except for heel-rise height. [ABSTRACT FROM AUTHOR]

Background: It remains controversial whether nonsurgical or surgical treatment provides better calf muscle strength recovery after an acute Achilles tendon rupture (ATR). Recent evidence has suggested that surgery might surpass nonsurgical treatment in restoring strength after an ATR. Purpose: To assess whether magnetic resonance imaging (MRI) findings could explain calf muscle strength deficits and the difference between nonsurgical and surgical treatments in restoring calf muscle strength. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: From 2009 to 2013, 60 patients with acute ATRs were randomized to surgery or nonsurgical treatment with an identical rehabilitation protocol. The primary outcome measure was the volume of calf muscles assessed using MRI at 3 and 18 months. The secondary outcome measures included fatty degeneration of the calf muscles and length of the affected Achilles tendon. Additionally, isokinetic plantarflexion strength was measured in both legs. Results: At 3 months, the study groups showed no differences in muscle volumes or fatty degeneration. However, at 18 months, the mean differences between affected and healthy soleus muscle volumes were 83.2 cm3 (17.7%) after surgery and 115.5 cm3 (24.8%) after nonsurgical treatment (difference between means, 33.1 cm3; 95% CI, 1.3-65.0; P = .042). The study groups were not substantially different in the volumes or fatty degeneration of other muscles. From 3 to 18 months, compensatory hypertrophy was detected in the flexor hallucis longus (FHL) and deep flexors in both groups. In the nonsurgical treatment group, the mean difference between affected and healthy FHL muscle volumes was −9.3 cm3 (12%) and in the surgical treatment group was −8.4 cm3 (10%) (P ≤ .001). At 18 months, Achilles tendons were, on average, 19 mm longer in patients treated nonsurgically compared with patients treated surgically (P < .001). At 18 months, surgically treated patients demonstrated 10% to 18% greater strength results (P = .037). Calf muscle isokinetic strength deficits for the entire range of ankle motion correlated with soleus atrophy (ρ = 0.449-0.611; P < .001). Conclusion: Treating ATRs nonsurgically with a functional rehabilitation protocol resulted in greater soleus muscle atrophy compared with surgical treatment. The mean Achilles tendon length was 19 mm longer after nonsurgical treatment than after the surgical treatment of ATRs. These structural changes partly explained the 10% to 18% greater calf muscle strength observed in patients treated with surgery compared with those treated nonsurgically. Registration: NCT02012803 (ClinicalTrials.gov identifier). [ABSTRACT FROM AUTHOR]

Objectives: To evaluate popliteal vein blood flow during calf muscle contraction in chronic venous disease (CVD) patients and healthy controls using ultrasound imaging and to investigate the relationship between venous blood flow and gastrocnemius muscle (GM) morphology. Methods: Thirty-one subjects participated in this study (mean age: 40.3 [11.8] years), 15 healthy controls and 16 with CVD (clinical classification: C1-4). Popliteal vein cross-sectional area and venous blood flow velocity (FV) were evaluated by Doppler ultrasound at baseline and during three sets of 10 tip-toe movement repetitions. Muscle thickness, muscle fascicle length and pennation angle of both medial and lateral GM were measured by ultrasound. Measures were repeated a week later in 17 participants in order to assess reproducibility with intraclass correlation coefficient (ICC) and Bland--Altman analysis. Results: Peak FV was lower in CDV group compared with Control group for both first (40.6 [11.8] versus 62.4 (22.1) cm²/second; P = 0.021) and last (30.4 [9.1] versus 49.5 (22.7) cm²/second; P = 0.024) contraction. In CVD group, peak FV during first contraction increased with GM's muscle fascicle length (r = 0.63; P = 0.041). Popliteal FV also increased with rising range of muscle fascicles pennation change between ankle dorsiflexion and plantar flexion (r = 0.70; P = 0.025). No associations were found between haemodynamics and medial or lateral GM thickness. Calf muscular architecture was similar in both CVD and control participants. Test-retest reliability of FV measured in the same session was high (ICC≈ 0.70) for measures taken in the first contraction of the set but lowered when using the last contraction (ICC<0.50). Reproducibility of ultrasound evaluation of calf pump is acceptable within the same session but is unsatisfactory when testing in separate days. Conclusion: Patients with moderate CVD have lower FV during calf muscles contraction but similar muscle anatomical characteristics compared with healthy controls. Changes in calf muscles flexibility and fatigue resistance may be investigated as possible causes of calf pump dysfunction. [ABSTRACT FROM AUTHOR]

The article determines whether the microvascular volume (MV) of the Achilles tendon increases in patients with Achilles tendinopathy (AT) compared with healthy controls during pre-exercise rest, after acute exercise and 24 hours after exercise. The study used real-time harmonic contrast-enhanced ultrasound (CEU) measurements of the MV of the Achilles tendon taken in several volunteers. Results showed acute exercise increases MV of the Achilles tendon in healthy patients and patients with AT.

Objectives: Exercise of the leg with external limb compression has been reported to be useful for preventing and reducing leg oedema. The aim of this study was to investigate the effects of leg gaiters on calf muscle pump activity. Methods: Continuous measurements of the interface pressure at the leg during exercise and determination of the femoral venous velocity at the groin during exercise were carried out in healthy volunteers with elastic stockings alone, leg gaiters alone and gaiters over the elastic stockings. Results: The greatest pressure difference between muscle contraction and relaxation during exercise was observed when gaiters were applied over the elastic stockings at the calf. Gaiters alone without elastic stockings led to a significantly greater pressure difference between muscle contraction and relaxation during exercise than elastic stockings alone (P < 0.01). A significantly higher value of the peak flow velocity of the femoral vein was observed with the combined use of gaiters and elastic stockings than the single use of elastic stockings. Conclusions: Leg gaiters have a beneficial effect of augmenting venous femoral blood flow during calf muscle pump activity in volunteers with a normal valve function of leg veins. [ABSTRACT FROM AUTHOR]

Background: Multiple percutaneous longitudinal tenotomies have been successfully undertaken in runners with isolated midportionAchilles tendinopathy (nodular lesions<2.5 cm) without any sign of paratendinopathy.Hypothesis: In the long term, minimally invasive multiple tenotomies allow the patient to remain involved in middle- and longdistancerunning. Clinical and ultrasound (US) evidence of paratendinopathy is a negative prognostic factor.Study Design: Case series study; Level of evidence, 4.Methods: A total of 39 patients were reviewed at an average follow-up of 17 years (range, 15-22 years) after US-guided multiplepercutaneous longitudinal tenotomies for chronic Achilles tendinopathy. The Victorian Institute of Sports Assessment–Achilles(VISA-A) questionnaire was completed by each patient, maximum calf circumference and isometric plantarflexion strength ofthe gastrocsoleus complex were measured in both the affected and contralateral legs, and functional assessment was scoredby the 4-point Boyden scale. Achilles tendon changes were also assessed according to the grayscale US grading system.Results: At the final follow-up, the maximum calf circumference and the strength in the operated leg were not significantly differentthan those measured preoperatively, but they were significantly lower than those on the contralateral side. This did notaffect patients’ daily or sports activities. All patients had returned to their preinjury working occupation; 20 patients were stillactive in middle- and long-distance running, with an average current level of sport and function that was 60% ± 13% comparedwith baseline status (before onset of symptoms). Thirty of 39 patients (77%) reported good or excellent outcomes according tothe Boyden assessment. On US assessment, the tendon was generally thicker than the contralateral asymptomatic tendon (average,7.0 vs 8.7 mm, respectively; P = .003). There was no significant difference (P > .05) when comparing patients with good orexcellent Boyden results versus those with fair or poor outcomes. The mean VISA-A score was 78.5, with no significant differencebetween patients with and without paratendinopathy on US assessment (P > .05). All of the patients who did not return to runningor who gave up sports activities had signs of paratendinopathy.Conclusion: This approach to the management of midportion Achilles tendinopathy is safe, has a low cost, and is effective in thelong term. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the use of either segmental muscle vibration and botulinum toxin-A injection or both for reduction of spasticity in multiple sclerosis patients. The study randomized 42 multiple sclerosis patients into three groups which were administered with muscle vibration, botulinum toxin, and both. Modified Ashworth Scale at knee and ankle shows reduction in all groups. Moreover, botulinum toxin only patients shows significant rise in knee and ankle spasticity.

The article reports a study which was conducted to determine whether the anterior cruciate ligament (ACL) exhibits fatigue behavior under strenuous, repetitive simulated pivot landings. The results revealed that the human ACL exhibits fatigue failure when pivot landings of 3 times body weight (3*BW) or more load the knee repeatedly within a short time span. A larger landing force and a smaller ACL cross-sectional area were both predictive of fewer cycles to ACL failure.

The article discusses a study by Nicola Maffulli and colleagues on the surgical procedure of semitendinosus autologous graft reconstruction to treat chronic Achilles tendon rupture. Patients were observed for an average of 8.2 years to compare their preoperative and postoperative anthropometric findings, in this study. The results revealed the procedure to be safe and minimally invasive, as most patients were rehabilitated with their normal and sports activity within 9 months.

Objectives: To verify whether a foot-sparing bandage is effective for patients who have undergone varicose vein surgery, being in the C2 class, having a normal deep venous system and actively walking. Methods: Ninety consecutive lower legs meeting the inclusion criteria underwent treatment with an inelastic foot-sparing bandage. Patient's satisfaction, efficacy and local effects were systematically documented. Results: The bandage was well tolerated and highly effective. Four of the first 20 cases experienced a slight morning oedema of the foot, which disappeared while walking. Thus, in the remaining cases we covered the foot and distal limb with a custom short tubular-shaped 'sock' providing 10 mmHg compression, only during the first 24 hours. Conclusion: The foot-sparing inelastic bandage is effective, cheap and tolerated by well-selected patients who have undergone varicose vein surgery. [ABSTRACT FROM AUTHOR]

The article reports a study which was conducted to examine whether muscle co-contraction and tibiofemoral compressive forces in women after undergoing anterior cruciate ligament reconstruction (ACLR) can be reduced through the use of a landing strategy that emphasizes greater hip and knee flexion. The results suggest that tibiofemoral compressive forces and muscle co-contraction can be reduced by use of a landing strategy that emphasizes greater hip and knee flexion.

Background: Gender differences exist in anterior cruciate ligament (ACL) cross-sectional area and lateral tibial slope. Biomechanical principles suggest that the direction of these gender differences should induce larger peak ACL strains in females under dynamic loading.Hypothesis: Peak ACL relative strain during a simulated pivot landing is significantly greater in female ACLs than male ACLs.Study Design: Controlled laboratory study.Methods: Twenty cadaveric knees from height- and weight-matched male and female cadavers were subjected to impulsive 3-dimensional test loads of 2 times body weight in compression, flexion, and internal tibial torque starting at 15° of flexion. Load cells measured the 3-dimensional forces and moments applied to the knee, and forces in the pretensioned quadriceps, hamstring, and gastrocnemius muscle equivalents. A novel, gender-specific, nonlinear spring simulated short-range and longer range quadriceps muscle tensile stiffness. Peak relative strain in the anteromedial bundle of the ACL (AM-ACL) was measured using a differential variable reluctance transducer, while ACL cross-sectional area and lateral tibial slope were measured using magnetic resonance imaging. A repeated-measures Mann-Whitney signed-rank test was used to test the hypothesis.Results: Female knees exhibited 95% greater peak AM-ACL relative strain than male knees (6.37% [2.53%] vs 3.26% [1.89%]; P = .004). Anterior cruciate ligament cross-sectional area and lateral tibial slope were significant predictors of peak AM-ACL relative strain (R2 = .59; P = .001).Conclusion: Peak AM-ACL relative strain was significantly greater in female than male knees from donors of the same height and weight. This gender difference is attributed to a smaller female ACL cross-sectional area and a greater lateral tibial slope.Clinical Relevance: Since female ACLs are systematically exposed to greater strain than their male counterparts, training and injury prevention programs should take this fact into consideration. [ABSTRACT FROM PUBLISHER]

Background: Ankle sprain is a common sports injury. While the effects of static constraints in stabilizing the ankle joint are relatively well understood, those of dynamic constraints are less clear and require further investigation.Purpose: This study was undertaken to evaluate the dynamic stability of the ankle joint during the landing phase of running and stop-jump maneuvers in athletes with and without chronic ankle instability (CAI).Study Design: Controlled laboratory study.Methods: Fifteen athletes with CAI and 15 age-matched athletes without CAI performed running and stop-jump landing tasks. The dynamic ankle joint stiffness, tibialis anterior (TA)/peroneus longus (PL) and TA/gastrocnemius lateralis (GL) co-contraction indices, ankle joint angle, and root-mean-square (RMS) of the TA, PL, and GL electromyographic signals were measured during each task.Results: During running, the CAI group exhibited a greater ankle inversion angle than the control group in the pre-landing phase (P = .012-.042) and a lower dynamic ankle joint stiffness in the post-landing phase (CAI: 0.109 ± 0.039 N·m/deg; control: 0.150 ± 0.068 N·m/deg; P = .048). In the stop-jump landing task, athletes with CAI had a significantly lower TA/PL co-contraction index during the pre-landing phase (CAI: 49.1 ± 19; control: 64.8 ± 16; P = .009). In addition, the CAI group exhibited a greater ankle inversion (P = .049), a lower peak eversion (P = .04), and a smaller RMS of the PL electromyographic signal in the post-landing phase (CAI: 0.73 ± 0.32; control: 0.51 ± 0.22; P = .04).Conclusion: Athletes with CAI had a relatively inverted ankle, reduced muscle co-contraction, and a lower dynamic stiffness in the ankle joint during the landing phase of sports maneuvers and this may jeopardize the stability of the ankle.Clinical Relevance: Sports training or rehabilitation programs should differentiate between the pre-landing and post-landing phases of sports maneuvers, and should educate athletes to land with an appropriate ankle position and muscle recruitment. [ABSTRACT FROM AUTHOR]

We determined whether more adverse calf muscle characteristics and poorer peripheral nerve function were associated with impairments in self-perceived physical functioning and walking ability in persons with lower extremity peripheral artery disease (PAD). Participants included 462 persons with PAD; measures included the ankle—brachial index (ABI), medical history, electrophysiologic characteristics of nerves, and computed tomography of calf muscle. Self-perceived physical functioning and walking ability were assessed using the 36-Item Short Form Health Survey (SF-36) and the Walking Impairment Questionnaire (WIQ). Results were adjusted for age, sex, race, ABI, body mass index, comorbidities, and other confounders. Lower calf muscle area was associated with a poorer SF-36 physical function (PF) score (overall p-trend < 0.001, 33.76 PF score for the lowest quartile versus 59.74 for the highest, pairwise p < 0.001) and a poorer WIQ walking distance score (p-trend = 0.001, 29.71 WIQ score for the lowest quartile versus 48.43 for the highest, pairwise p < 0.001). Higher calf muscle percent fat was associated with a poorer SF-36 PF score (p-trend < 0.001, 53.76 PF score for the lowest quartile versus 40.28 for the highest, pairwise p = 0.009). Slower peroneal nerve conduction velocity was associated with a poorer WIQ speed score ( p-trend = 0.023, 30.49 WIQ score for the lowest quartile versus 40.48 for the highest, pairwise p = 0.031). In summary, adverse calf muscle characteristics and poorer peripheral nerve function are associated significantly and independently with impairments in self-perceived physical functioning and walking ability in PAD persons. [ABSTRACT FROM AUTHOR]

Background: The posterolateral corner of the knee consists of static and dynamic stabilizing structures. Knee injuries often include the posterolateral structures. The popliteus muscle-tendon unit is known as the major dynamic stabilizer of the posterolateral corner.Hypothesis: The dynamic stabilization of the posterolateral structures of the knee via the popliteus muscle-tendon unit during a squatting exercise follows a constant activation pattern.Study Design: Controlled laboratory study.Methods: Within the pilot study, 6 volunteers performed 2 exercises to verify the electrode position scheme and to analyze crosstalk. In the main study 2 static exercises (standing and standing with knees flexed 90°) and 2 dynamic exercises (isolated popliteus muscle activation and squats) were recorded in 17 volunteers. Electromyograms were obtained of the popliteus, medial and lateral gastrocnemius, and quadriceps muscles. Knee angle-related muscle activity was recorded.Results: In the pilot study it was assumed that the chosen electrode position allowed selective measurement of popliteus muscle activity. In the main study the mean popliteus onset angle was 43° ± 14° of flexion; activity lasted through the reversal point of the squat to 58° ± 21° of flexion during extension movement. Popliteus activity during all testing cycles revealed that the activity in the standing position is the smallest. The highest activity was recorded during the squat and the popliteus muscle-tendon unit exercise.Conclusion: This study demonstrates an activation pattern of the popliteus muscle-tendon unit with high interindividual differences in the onset angles. A constant activation during the reversal phase of the squatting exercise could be observed.Clinical Relevance: Reconstructive procedures of the posterolateral structures often include reconstruction of the popliteus muscle-tendon unit. Reconstructive procedures are usually done in a static manner, thus not addressing the dynamic stabilizing structure in a true functional way. The findings of the current study may be a useful contribution to the ongoing discussion of this topic. [ABSTRACT FROM AUTHOR]

Background: A less-invasive technique to reconstruct chronic Achilles tendon rupture with transfer of the tendon of peroneus brevis is suitable in patients with a tendon gap less than 6 cm.Purpose: To report the results of a longitudinal study on reconstruction of chronic Achilles tendon rupture using a less-invasive peroneus brevis repair through 2 paramidline incisions.Study Design: Case series; Level of evidence, 4.Methods: Thirty-two patients underwent surgery for chronic Achilles tendon rupture with a tendon gap during surgery less than 6 cm, occurring between 60 days and 9 months preoperatively. All participants were prospectively followed for 5 to 8 years; final review was performed at 48.4 ± 13.5 months from the operation. Clinical and functional assessment (anthropometric measurements, isometric strength, postoperative Achilles tendon total rupture score) was performed.Results: All patients were able to walk on tiptoes, and no patient used a heel lift or walked with a visible limp. No patient developed a clinically evident deep vein thrombosis or sustained a rerupture. Five patients were managed nonoperatively after a superficial infection of one of the surgical wounds. At final review, the maximum calf circumference remained significantly decreased in the operated leg (39.2 ± 6.2 cm [side with rupture] vs 40.9 ± 7.0 cm [uninjured side]; P = .04). The operated limb was significantly less strong than the nonoperated one (231.2 ± 132.4 N vs 275.3 ± 150.2 N; P = .033). The Achilles tendon total rupture score at final follow-up was 92.5 ± 14.2.Conclusion: The management of chronic Achilles tendon tears by a less-invasive peroneus brevis repair is technically demanding but safe. It allows good recovery, even in patients with a chronic rupture of 9 months’ duration. These patients should be warned that they are at risk for postoperative complications and that their ankle plantar flexion strength is likely to be reduced. [ABSTRACT FROM PUBLISHER]