Effect of foot stato-dynamic disorders on hemodynamics of the lower limb using strain-gauge plethysmography

BACKGROUND

The plantar venous pump (PVP), composed of deep plantar veins, is the most distal contributor to venous return from the lower limbs. A pressing need still exists to assess how plantar muscle contraction and gait affect PVP function, how foot stato-dynamic disorders (FSDs) can contribute to venous insufficiency, and how venous return can be optimally stimulated. Our first objective is to compare the venous blood hemodynamics in lower limbs between healthy subjects with a FSD and healthy subjects without a FSD to understand the influence of foot morphology in the performance of the PVP. Our second objective is to evaluate whether PVP function varies with different plantar pressures.

METHODS

A total of 52 healthy volunteers (26 feet with a normal arch as the control group and 26 feet with dysmorphism [13 flat feet and 13 hollow feet]) were included. Strain-gauge plethysmography was performed 8 cm above the medial malleolus at different conditions of PVP stimulation: (1) toe flexion, (2) intermittent pneumatic compression (IPC) with and without an insole, and (3) 3-km/h speed walking on a treadmill barefoot, with shoes, and with shoes and insoles. From the strain-gauge plethysmography, we measured the venous blood ejection fraction (EF). From the pressure sensor placed at the midfoot on the plantar arch during IPC, we obtained the maximal pressure (N/cm2).

RESULTS

Toe flexion allowed for ejection of an average of 20% of the total venous volume in both groups. IPC and gait generated a mean EF superior to 100% of the available venous volume. The maximal pressure applied at the midfoot during IPC was lower than the pressure set. No significant differences in the EF or maximal pressure were observed between the two groups. The mean EF was not significantly affected for the pronator and supinator walkers compared with those with normal walking dynamics. Wearing shoes did not significantly affect the mean EF. However, wearing insoles during gait significantly increased the venous return in feet with plantar dysmorphism.

CONCLUSIONS

To the best of our knowledge, this clinical study is the first to assess the PVP function in 52 healthy volunteers with and without FSDs. We found that wearing shoes did not significantly affect PVP efficiency but that wearing morphologically adapted insoles significantly improved the venous return in the dysmorphic feet. In our sample of healthy volunteers, the differences observed between the control group and feet with FSDs were not statistically significant.

The relationship between pes planus and venous insufficiency

INTRODUCTION

The presence of pes planus may be responsible for the disorder of venous return during ambulation. Our aim in this study is to reveal that the risk of venous insufficiency may be increased in patients with pes planus.

METHODS

A total of 59 patients with 29 bilateral pes planus and 30 normal arches included in the study. Djian Annonier angle measurement, bilateral lower extremity venous Doppler ultrasonography (USG), foot function index (AFI), Comprehensive Classification System for Chronic Venous Disorders (CEAP) clinical scoring and Short Form-36 (SF-36) was evaluated.

RESULTS

There was a statistically significant difference in AFI total, AFI pain, AFI disability and AFI activity limitation scores, bilateral lower extremity doppler USG and CEAP clinical scores in the patient group compared to the control group.

CONCLUSION

These findings suggest that there may be a relationship between pes planus and venous insufficiency. However, large-scale studies with more patient involvement are needed.

Phlebological insole: Can it help in the lymphoedema treatment? A scoping review

BACKGROUND

The treatment of lymphoedema requires a multi-professional and interdisciplinary approach. Despite being prescribed in the management of lymphatic disorders, the effectiveness of the phlebological insoles is still under investigation.

AIM

This scoping review aims to identify and analyse evidence regarding the efficacy of phlebological insoles as a conservative intervention for lower limb lymphoedema.

METHOD

The following databases were searched up to November 2022: PubMed, Cochrane Library, CINAHL Complete, PEDro and Scopus. Preventive and conservative interventions were considered. Studies considering people with lower limb oedema, of any age and type of oedema, were eligible for inclusion. No restrictions in terms of language, year of publication, study design and type of publication were applied. Additional studies were sought through grey literature.

RESULTS

From 117 initial records, 3 studies met the inclusion criteria. Two quasi-experimental studies and one randomised cross-over study were included. The results of the examined studies confirmed the positive effects of insoles usage and foot and ankle mobility on the venous return.

CONCLUSION

This scoping review provided an overview of the topic. The studies analysed in this scoping review have shown that insoles seem to be beneficial in reducing the lower limb oedema in healthy individuals. However, there are still no comprehensive trials confirming this evidence on people with lymphoedema. The small number of identified articles, the selection of participants not affected by lymphoedema, the use of heterogeneous devices in terms of modifications and materials highlight the need of further investigations. Future trails should include people affected by lymphoedema, address the choice of materials in manufacturing the insoles and take in consideration the patients' adherence to the device and concordance to the treatment.

Post-thrombotic syndrome

Post-thrombotic syndrome (PTS) is a chronic venous insufficiency manifestation following an episode of deep-vein thrombosis (DVT). It is an important and frequent long-term adverse event of proximal DVT affecting 20-50% of patients. This position paper integrates data guiding clinicians in deciding PTS diagnosis, treatment and follow-up.

Slow-Speed Resistance Training Increases Skeletal Muscle Contractile Properties and Power Production Capacity in Elite Futsal Players

The purpose of this study was to explore the effects of slow-speed resistance training with low intensity (SRT) on muscle power output in elite futsal players with respect to traditional resistance training. The authors hypothesized that the muscle deoxygenation during SRT causes early recruitment of fast twitch fibers that would positively affect strength and power performance. Thirty male elite futsal players were recruited and randomly assigned either to SRT group or to traditional resistance training (TRT) group. All players underwent an 8-weeks experimental protocol consisting of 2 training sessions per week at both leg curl and leg extension machines. In the SRT, players lifted 50% of one maximum repetition (1RM) involving 3 s for eccentric and concentric actions. In the TRT, players lifted 80% of 1RM involving 1 s for eccentric and concentric actions. All players were tested twice (pre and post) for sprint and jump performances, maximal isometric voluntary contraction (MVC) and maximal isokinetic peak torque (Peak TQ) and total work (TW) at 60 and 120°/s (on knee extensors and flexors). The two groups presented remarkable differences in the within-group changes for all the variables. SRT exhibited greater improvements in both Peak TQ and TW for knee extensors and flexors at 120°/s. Conversely, TRT showed greater improvements in MVC, and in both Peak TQ and TW for knee extensors and flexors at 60°/s, except for Peak TQ of the knee extensors, where no significant difference was found between TRT and SRT. Countermovement jump showed a decrease in eccentric time and an increase in concentric force in SRT group. SRT and TRT resulted effective to enhance the strength performance indices during the 8-weeks experimental protocol. Peak torque at 120°/s explained more of the contractile characteristic effects of SRT training than MVC, suggesting that slow-speed training can cause fast twitch fibers hypertrophy in elite athletes. Since slow-speed training is supposed to produce a decreased exercise-induced muscle damage, SRT method is a suitable option in strength training for futsal and team sports.

The effects of shoe type on lower limb venous status during gait or exercise: A systematic review

This systematic review evaluated the literature pertaining to the effect of shoes on lower limb venous status in asymptomatic populations during gait or exercise. The review was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The PubMed-NCBI, EBSCO Host, Cochrane Library and Science Direct databases were searched (March 2019) for words around two concepts: shoes and venous parameters. The inclusion criteria were as follows: (1) the manuscript had to be published in an English-language peer-reviewed journal and the study had to be observational or experimental and (2) the study had to suggest the analysis of many types of shoes or orthotics on venous parameters before, during and/or after exercise. Out of 366 articles, 60 duplications were identified, 306 articles were analyzed, and 13 articles met the eligibility criteria after screening and were included. This review including approximately 211 participants. The methodological rigor of these studies was evaluated with the modified Downs and Black quality index. Nine studies investigated the effect of shoes on blood flow parameters, two on venous pressure and two on lower limb circumferences with exercise. Evidence was found that unstable shoes or shoes with similar technology, sandals, athletic or soft shoes, and customized foot orthotics elicited more improvement in venous variables than high-heeled shoes, firm shoes, ankle joint immobilization and barefoot condition. These venous changes are probably related to the efficiency of muscle pumps in the lower limbs, which in turn seem to be dependent on shoe features associated with changes in the kinetics, kinematics and muscle activity variables in lower limbs during gait and exercise.

The 2020 update of the CEAP classification system and reporting standards

The CEAP (Clinical-Etiology-Anatomy-Pathophysiology) classification is an internationally accepted standard for describing patients with chronic venous disorders and it has been used for reporting clinical research findings in scientific journals. Developed in 1993, updated in 1996, and revised in 2004, CEAP is a classification system based on clinical manifestations of chronic venous disorders, on current understanding of the etiology, the involved anatomy, and the underlying venous pathology. As the evidence related to these aspects of venous disorders, and specifically of chronic venous diseases (CVD, C2-C6) continue to develop, the CEAP classification needs periodic analysis and revisions. In May of 2017, the American Venous Forum created a CEAP Task Force and charged it to critically analyze the current classification system and recommend revisions, where needed. Guided by four basic principles (preservation of the reproducibility of CEAP, compatibility with prior versions, evidence-based, and practical for clinical use), the Task Force has adopted the revised Delphi process and made several changes. These changes include adding Corona phlebectatica as the C4c clinical subclass, introducing the modifier "r" for recurrent varicose veins and recurrent venous ulcers, and replacing numeric descriptions of the venous segments by their common abbreviations. This report describes all these revisions and the rationale for making these changes.

Functional Electrical Stimulation: A Possible Strategy to Improve Muscle Function in Central Core Disease?

Central Core Disease (CCD) is a congenital myopathy characterized by presence of amorphous central areas (or cores) lacking glycolytic/oxidative enzymes and mitochondria in skeletal muscle fibers. Most CCD families are linked to mutations in ryanodine receptor type-1 (RYR1), the gene encoding for the sarcoplasmic reticulum (SR) Ca²⁺ release channel of skeletal muscle. As no treatments are available for CCD, currently management of patients is essentially based on a physiotherapic approaches. Functional electrical stimulation (FES) is a technique used to deliver low energy electrical impulses to artificially stimulate selected skeletal muscle groups. Here we tested the efficacy of FES in counteracting muscle loss and improve function in the lower extremities of a 55-year-old female patient which was diagnosed with CCD at the age of 44. Genetic screening of the RyR1 gene identified a missense mutation (c.7354C>T) in exon 46 resulting in an amino acid substitution (p.R2452W) and a duplication (c.12853_12864dup12) in exon 91. The patient was treated with FES for 26 months and subjected before, during, and after training to a series of functional and structural assessments: measurement of maximum isometric force of leg extensor muscles, magnetic resonance imaging, a complete set of functional tests to assess mobility in activities of daily living, and analysis of muscle biopsies by histology and electron microscopy. All results point to an improvement in muscle structure and function induced by FES suggesting that this approach could be considered as an additional supportive measure to maintain/improve muscle function (and possibly reduce muscle loss) in CCD patients.

Rehabilitation of patients with venous diseases of the lower limbs: State of the art

BACKGROUND

To date, no document comprehensively focused on the complex issue of the rehabilitation of chronic venous diseases of the lower limbs.

METHOD

This article overviews and summarizes current strategies concerning venous rehabilitation of lower limbs.

RESULTS

Venous rehabilitation is based on four main strategies: (1) lifestyle adaptations and occupational therapies; (2) physical therapies; (3) adapted physical activities; (4) psychological and social support. Rehabilitative protocols must be tailored to the specific needs of each patient, depending on the severity of chronic venous disease and on the location and pattern of venous lesion(s), but also on age, motor deficits, co-morbidities and psychosocial conditions.

CONCLUSIONS

Venous rehabilitation consists of non-pharmacologic and non-surgical interventions aiming at prevention of venous disease progression and complications, reduction of symptoms and improvement of quality of life. Well-designed clinical trials are required to evaluate the efficacy of the described rehabilitative protocols in influencing the evolution of venous disorders.

Anatomy of the veno-muscular pumps of the lower limb

OBJECTIVE

To study the anatomy of the veno-muscular pumps of the lower limb, particularly the calf pump, the most powerful of the lower limb, and to confirm its crucial importance in venous return.

METHODS

In all, 400 cadaveric limbs were injected with green Neoprene latex followed by an anatomical dissection.

RESULTS

The foot pump is the starter of the venous return. The calf pump can be divided into two anatomical parts: the leg pump located in the veins of the soleus muscle and the popliteal pump ending in the popliteal vein with the unique above-knee collector of the medial gastrocnemial veins. At the leg level, the lateral veins of the soleus are the bigger ones. They drain vertically into the fibular veins. The medial veins of the soleus, smaller, join the posterior tibial veins horizontally. At the popliteal level, medial gastrocnemial veins are the largest veins, which end uniquely as a large collector into the popliteal vein above the knee joint. This explains the power of the gastrocnemial pump: during walking, the high speed of the blood ejection during each muscular systole acts like a nozzle creating a powerful jet into the popliteal vein. This also explains the aspiration (Venturi) effect on the deep veins below. Finally, the thigh pump of the semimembranosus muscles pushes the blood of the deep femoral vein together with the quadriceps veins into the common femoral vein.

CONCLUSION

The veno-muscular pumps of the lower limb create a chain of events by their successive activation during walking. They play the role of a peripheral heart, which combined with venous valves serve to avoid gravitational reflux during muscular diastole. A stiffness of the ankle or/and the dispersion of the collectors inside the gastrocnemius could impair this powerful pump and so worsen venous return, causing development of severe chronic venous insufficiency.

Compression versus inner sole for venous patients with foot static disorders: a prospective trial comparing symptoms and quality of life

OBJECTIVE

To prospectively compare the improvement in quality of life and symptoms achieved when using two treatments-medical compression stockings and inner sole-in subjects with symptomatic chronic venous disease in the presence of foot static disorders.

MATERIALS AND METHODS

This prospective study included 24 patients with a symptomatic chronic venous disease associated with foot static disorders. The basic CEAP was used to classify the patients. The venous symptoms were recorded using a 10-point visual analog scale and scored using a customized questionnaire. Patient-reported quality of life data were acquired using a CIVIC questionnaire. A standardized measurement of the Djian-Annonier angle was used to quantify the foot static disorders. We compared the use of the following two treatments: medical compression stockings (18 mm of Hg) and inner sole. For this comparison, we used a crossover technique over 4 successive weeks.

RESULTS

One male and 23 female patients were included in this study. We found significant improvement in quality of life scores when only medical compression stockings were used (p < 0.005), only inner sole were used (p < 0.01) and also when both treatments were used together (p < 0.001), compared with no treatment. This was mainly observed for the somatic component of CIVIC. The symptoms of pain, heaviness, swollen feeling, and cramps were significantly improved by the two treatments, whether given separately (p < 0.001) or together (p < 0.0001). No additive effect of the treatments was observed.

CONCLUSION

This study suggests that a number of leg symptoms occurring in varicose veins patients are not likely to have a venous origin. They are frequently related to a foot static disorder, which is responsible for postural changes. This study also strongly demonstrates the need for correction of the foot static disorder if such a disorder is present in any patient with chronic venous disease. The use of the inner sole will improve the symptoms and also the quality of life with an efficiency that is almost equal to that provided by the medical compression stockings and the combined use of both treatments is recommended.

Anatomy of the foot venous pump: physiology and influence on chronic venous disease

The aim of this paper is to demonstrate the location of the venous foot pump using an anatomical study. Four hundred cadaveric feet were injected with green neoprene latex followed by a dissection. A coloured segmentation of the venous system was achieved. The Lejars’ concept of the venous sole of the foot is incorrect: the true blood venous reservoir of the foot is located deeply in the plantar veins, between the plantar muscles. The medial and mostly lateral plantar veins converge into the plexus shaped calcaneal crossroad, where the blood is ejected upwards into the two posterior tibial veins. In addition, the several medial perforators of the foot directly connect the deep system (medial plantar veins) to the superficial venous system (medial marginal vein). This forms a true ‘medial functional unit’ which is unique in the limb given its directional flow is from deep to superficial. In conclusion, the plantar veins play an important role in the physiology of the venous return since a venous reservoir of 25 mL of blood is mobilized upwards with each step during walking. Therefore, the impairment of the foot pump by a static foot disorder should be considered as an important risk factor for chronic venous disease, and should be evaluated and corrected in any patient with venous insufficiency.