AUCTORES
Commentary
*Corresponding Author: Marinko Erceg, Private Orthopaedic Surgery Clinic, Marinko Erceg Pty. Ltd., Split, Croatia.
Citation: Erceg D., Erceg M., Bečić K., Bekavac J., (2023), What Is the Size and Delineation of The Horizontal Lever Arm K1 In Pauwel's Hip Biomechanics? International Journal of Clinical Case Reports and Reviews, 15(2); DOI:10.31579/2690-4861/351
Copyright: © 2023, Marinko Erceg. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Received: 13 November 2023 | Accepted: 04 December 2023 | Published: 13 December 2023
Keywords: delineation; Pauwel's hip biomechanics; horizontal lever arm k1; hip displacement
Every object around us is exposed to the actions of mechanical forces as well as laws of statics and dynamics. This can be particularly well seen on the locomotor system, and special attention is devoted to the biomechanics of the hip. This was a special area of interest for Pauwels. When standing on both legs, both of the hips equally carry the weight of the body (above the hip line). It is believed that upper body amounts to 2/3 of the total body weight (2/3 G), while lower extremities amount to 1/3 of the bodyweight. Therefore, when standing on both legs, each hip carries up to 1/3 of body weight (G / 3), which is a relatively small load for the hip joint. The direction of the force that acts on hips is vertical.
Every object around us is exposed to the actions of mechanical forces as well as laws of statics and dynamics. This can be particularly well seen on the locomotor system, and special attention is devoted to the biomechanics of the hip. This was a special area of interest for Pauwels. When standing on both legs, both of the hips equally carry the weight of the body (above the hip line). It is believed that upper body amounts to 2/3 of the total body weight (2/3 G), while lower extremities amount to 1/3 of the bodyweight. Therefore, when standing on both legs, each hip carries up to 1/3 of body weight (G / 3), which is a relatively small load for the hip joint. The direction of the force that acts on hips is vertical (Figure 1). However, the load on the hip while standing on one leg, i.e., walking, is very different and far more unfavorable for the hip. Pauwels presented the hip under load as a balanced horizontal scale with the center of rotation in the center of the hip, and force momentums M1 and M2 on the both sides. The force moment M1 is the product of medial arm of the scale (bodyweight lever arm) k1 and the weight of the body G, and the momentum M2, a product of lateral arm of the scale (muscle force lever arm) k2 and the force of the hip abductor F. In order to keep the pelvis horizontal while standing on one leg M1 should be equal to M2, (k1 · G = k2 · F). As k1 arm of the adult is approximately 3 times longer than the k2 arm, the muscular force F must be about 3 times the weight of body G. From this Pauwels concludes that while standing on one leg the total load on the hip in adults is approximately 4 times the bodyweight (R ≈ 4 G). According to the same author force R is inclined to the vertical axis at an angle of 16 ° in the frontal plane (Figure 2,3), [1]. The fact that the hip joint is loaded with 4 body weights makes it the most heavily loaded joint in the human body.
Figure 1: In position standing on both legs each hip is loaded with 1/3 of the body weight G. Figure 2: Pauwels shematic of the hip biomechanics. Lever k1 is from the center of the hip joint to the line going vertically at the border of the foramen obturatum on side of the raised leg. Figure 3: Total loading when standing on one leg, according to Pauwels is about 4 G.
The Pauwels schematic can be well used to explain the hip balance when the center of the femoral head is not displaced from its natural position in the acetabulum, but it can't be used to depict biomechanical relationships in the dislocated hip when the femoral head is laterally and cranially displaced from the acetabulum. This is shown in the works of Erceg M. where the muscle force lever arm (k2) is shown in a different way, not horizontally, as shown by Pauwels, but more or less vertical (figure 4,5) [2]. In hip displacement the femur is moved laterally, thus increasing the value of the horizontal lever k1, but it is also moved cranially, thus reducing the vertical lever k2. Both have an adverse effect on the hip biomechanics. The hip balance is disrupted, and to keep the balance (to keep the pelvis horizontal) the hip abductors would have to provide even more strength thus burdening the hip even more. Such strength hip abductors can't provide, because their origin and insertion are brought closer. There is a relative insufficiency of the hip abductor and thus limping.
In this paper we are not discussing the muscular force lever k2 (whether it is horizontal or vertical) but horizontal lever k1 over which the weight of the body of G acts. Pauwels' scheme shows that the k1 lever starts from the center of the hip, crosses the middle of the pelvis in the frontal plane and reaches the vertical line of the obturator foramen on the side of the raised leg. On this line there is a body weight vector G (figure 2,3,5).
Figure 4: Hip abductor muscles act over vertical lever k2, whose length changes in situation of hip dislocation. Figure 5: New way of presentation hip biomechanics. Lever k1 reaches to the border of the obturatum foramen on the side of raised leg.
However, at the same time, there are images of numerous other authors who use Pauwels schematic but the lever k1 on those pictures is not the same length. On some of the illustrations, the k1 lever represents the distance from the center of the hip to the middle of the pelvis midline, passing through the symphysis of pubis in the frontal plane with the body weight vector G on it (figure 6,7) [3,4,5,6], while in other images, k1 is depicted as shown by Pauwels (Figure 8), [7]. Frequently, such images are used before and after the hip Aloarthroplasty. Hence, the size of the horizontal arm k1 is not equal in all of the images.
Figure 6: On this X ray of the pelvis with both hips, lever k1 reaches only to the middle of pelvis (vertical line passing pubic symphysis). Why? Figure 7: Presentation of hip biomechanics after hip Aloarthroplasty. Lever k1 reaches to the middle of the pelvis. Why? Figure 8: Presentation of hip biomechanics after hip Aloarthroplasty. Lever k1 reaches to the middle of the pelvis. Why?
The line on which the body weight vector G is located is moved (according to Pauwels) to, approximately, the obturator foramen on the side of the raised leg, because while standing on one leg, the burdened hip does not carry the entire body weight, but only the weight of the body above the level of the hip with the weight of the other (raised) leg. Therefore, the leg on which we stand does not participate in the body's weight, and burdening the hip, while the raised leg does, and for this reason, the line on which the weight vector of the body lies (force G) is moved towards the raised leg. Therefore, the length of the lever arm k1 is shown as the distance from the hip center to the obturator foramen of the pelvis on the side of the raised leg (figs. 2,3,5). Due to the fact that the burdened leg does not participate in the load of the hip, the force moment M1 is k1 · 5/6 G (fig. 8).
If we, in order to simplify the calculation, accept the fact that the body weight vector G is not 5/6 G, but G (whole body weight), then it would make sense to include the "shorter" horizontal lever k1 (figs. 6,7) that reaches the center line on which the body weight vector G lies (in the frontal plane it is a pubic symphysis). Then the force momentum M1 would be approximate in both cases, but in the case of the "shorter" lever arm k1 the total load force on the hip R would be more vertical than in the case of the "longer" lever arm k1, that results from Pawels' original schematic.
Authors do not understand the reason for this balance representation in terms of lever arm k1 size. We think that the length of the k1 lever arm is from the center of the hip to the vertical line passing through the edge of the obturator foramen on the pelvic side of the raised leg and body weight G is on that vertical line, not on the line passing through the pubic symphysis in the frontal plane.
This different way of presenting biomechanics of the hip can confuse younger colleagues, especially those who are at the beginning of their orthopedic education and training.
The author declares no competing interests.
Clearly Auctoresonline and particularly Psychology and Mental Health Care Journal is dedicated to improving health care services for individuals and populations. The editorial boards' ability to efficiently recognize and share the global importance of health literacy with a variety of stakeholders. Auctoresonline publishing platform can be used to facilitate of optimal client-based services and should be added to health care professionals' repertoire of evidence-based health care resources.
Journal of Clinical Cardiology and Cardiovascular Intervention The submission and review process was adequate. However I think that the publication total value should have been enlightened in early fases. Thank you for all.
Journal of Women Health Care and Issues By the present mail, I want to say thank to you and tour colleagues for facilitating my published article. Specially thank you for the peer review process, support from the editorial office. I appreciate positively the quality of your journal.
Journal of Clinical Research and Reports I would be very delighted to submit my testimonial regarding the reviewer board and the editorial office. The reviewer board were accurate and helpful regarding any modifications for my manuscript. And the editorial office were very helpful and supportive in contacting and monitoring with any update and offering help. It was my pleasure to contribute with your promising Journal and I am looking forward for more collaboration.
We would like to thank the Journal of Thoracic Disease and Cardiothoracic Surgery because of the services they provided us for our articles. The peer-review process was done in a very excellent time manner, and the opinions of the reviewers helped us to improve our manuscript further. The editorial office had an outstanding correspondence with us and guided us in many ways. During a hard time of the pandemic that is affecting every one of us tremendously, the editorial office helped us make everything easier for publishing scientific work. Hope for a more scientific relationship with your Journal.
The peer-review process which consisted high quality queries on the paper. I did answer six reviewers’ questions and comments before the paper was accepted. The support from the editorial office is excellent.
Journal of Neuroscience and Neurological Surgery. I had the experience of publishing a research article recently. The whole process was simple from submission to publication. The reviewers made specific and valuable recommendations and corrections that improved the quality of my publication. I strongly recommend this Journal.
Dr. Katarzyna Byczkowska My testimonial covering: "The peer review process is quick and effective. The support from the editorial office is very professional and friendly. Quality of the Clinical Cardiology and Cardiovascular Interventions is scientific and publishes ground-breaking research on cardiology that is useful for other professionals in the field.
Thank you most sincerely, with regard to the support you have given in relation to the reviewing process and the processing of my article entitled "Large Cell Neuroendocrine Carcinoma of The Prostate Gland: A Review and Update" for publication in your esteemed Journal, Journal of Cancer Research and Cellular Therapeutics". The editorial team has been very supportive.
Testimony of Journal of Clinical Otorhinolaryngology: work with your Reviews has been a educational and constructive experience. The editorial office were very helpful and supportive. It was a pleasure to contribute to your Journal.
Dr. Bernard Terkimbi Utoo, I am happy to publish my scientific work in Journal of Women Health Care and Issues (JWHCI). The manuscript submission was seamless and peer review process was top notch. I was amazed that 4 reviewers worked on the manuscript which made it a highly technical, standard and excellent quality paper. I appreciate the format and consideration for the APC as well as the speed of publication. It is my pleasure to continue with this scientific relationship with the esteem JWHCI.
This is an acknowledgment for peer reviewers, editorial board of Journal of Clinical Research and Reports. They show a lot of consideration for us as publishers for our research article “Evaluation of the different factors associated with side effects of COVID-19 vaccination on medical students, Mutah university, Al-Karak, Jordan”, in a very professional and easy way. This journal is one of outstanding medical journal.
Dear Hao Jiang, to Journal of Nutrition and Food Processing We greatly appreciate the efficient, professional and rapid processing of our paper by your team. If there is anything else we should do, please do not hesitate to let us know. On behalf of my co-authors, we would like to express our great appreciation to editor and reviewers.
As an author who has recently published in the journal "Brain and Neurological Disorders". I am delighted to provide a testimonial on the peer review process, editorial office support, and the overall quality of the journal. The peer review process at Brain and Neurological Disorders is rigorous and meticulous, ensuring that only high-quality, evidence-based research is published. The reviewers are experts in their fields, and their comments and suggestions were constructive and helped improve the quality of my manuscript. The review process was timely and efficient, with clear communication from the editorial office at each stage. The support from the editorial office was exceptional throughout the entire process. The editorial staff was responsive, professional, and always willing to help. They provided valuable guidance on formatting, structure, and ethical considerations, making the submission process seamless. Moreover, they kept me informed about the status of my manuscript and provided timely updates, which made the process less stressful. The journal Brain and Neurological Disorders is of the highest quality, with a strong focus on publishing cutting-edge research in the field of neurology. The articles published in this journal are well-researched, rigorously peer-reviewed, and written by experts in the field. The journal maintains high standards, ensuring that readers are provided with the most up-to-date and reliable information on brain and neurological disorders. In conclusion, I had a wonderful experience publishing in Brain and Neurological Disorders. The peer review process was thorough, the editorial office provided exceptional support, and the journal's quality is second to none. I would highly recommend this journal to any researcher working in the field of neurology and brain disorders.
Dear Agrippa Hilda, Journal of Neuroscience and Neurological Surgery, Editorial Coordinator, I trust this message finds you well. I want to extend my appreciation for considering my article for publication in your esteemed journal. I am pleased to provide a testimonial regarding the peer review process and the support received from your editorial office. The peer review process for my paper was carried out in a highly professional and thorough manner. The feedback and comments provided by the authors were constructive and very useful in improving the quality of the manuscript. This rigorous assessment process undoubtedly contributes to the high standards maintained by your journal.
International Journal of Clinical Case Reports and Reviews. I strongly recommend to consider submitting your work to this high-quality journal. The support and availability of the Editorial staff is outstanding and the review process was both efficient and rigorous.
Thank you very much for publishing my Research Article titled “Comparing Treatment Outcome Of Allergic Rhinitis Patients After Using Fluticasone Nasal Spray And Nasal Douching" in the Journal of Clinical Otorhinolaryngology. As Medical Professionals we are immensely benefited from study of various informative Articles and Papers published in this high quality Journal. I look forward to enriching my knowledge by regular study of the Journal and contribute my future work in the field of ENT through the Journal for use by the medical fraternity. The support from the Editorial office was excellent and very prompt. I also welcome the comments received from the readers of my Research Article.
Dear Erica Kelsey, Editorial Coordinator of Cancer Research and Cellular Therapeutics Our team is very satisfied with the processing of our paper by your journal. That was fast, efficient, rigorous, but without unnecessary complications. We appreciated the very short time between the submission of the paper and its publication on line on your site.
I am very glad to say that the peer review process is very successful and fast and support from the Editorial Office. Therefore, I would like to continue our scientific relationship for a long time. And I especially thank you for your kindly attention towards my article. Have a good day!
"We recently published an article entitled “Influence of beta-Cyclodextrins upon the Degradation of Carbofuran Derivatives under Alkaline Conditions" in the Journal of “Pesticides and Biofertilizers” to show that the cyclodextrins protect the carbamates increasing their half-life time in the presence of basic conditions This will be very helpful to understand carbofuran behaviour in the analytical, agro-environmental and food areas. We greatly appreciated the interaction with the editor and the editorial team; we were particularly well accompanied during the course of the revision process, since all various steps towards publication were short and without delay".
I would like to express my gratitude towards you process of article review and submission. I found this to be very fair and expedient. Your follow up has been excellent. I have many publications in national and international journal and your process has been one of the best so far. Keep up the great work.
We are grateful for this opportunity to provide a glowing recommendation to the Journal of Psychiatry and Psychotherapy. We found that the editorial team were very supportive, helpful, kept us abreast of timelines and over all very professional in nature. The peer review process was rigorous, efficient and constructive that really enhanced our article submission. The experience with this journal remains one of our best ever and we look forward to providing future submissions in the near future.
I am very pleased to serve as EBM of the journal, I hope many years of my experience in stem cells can help the journal from one way or another. As we know, stem cells hold great potential for regenerative medicine, which are mostly used to promote the repair response of diseased, dysfunctional or injured tissue using stem cells or their derivatives. I think Stem Cell Research and Therapeutics International is a great platform to publish and share the understanding towards the biology and translational or clinical application of stem cells.
I would like to give my testimony in the support I have got by the peer review process and to support the editorial office where they were of asset to support young author like me to be encouraged to publish their work in your respected journal and globalize and share knowledge across the globe. I really give my great gratitude to your journal and the peer review including the editorial office.
I am delighted to publish our manuscript entitled "A Perspective on Cocaine Induced Stroke - Its Mechanisms and Management" in the Journal of Neuroscience and Neurological Surgery. The peer review process, support from the editorial office, and quality of the journal are excellent. The manuscripts published are of high quality and of excellent scientific value. I recommend this journal very much to colleagues.
Dr.Tania Muñoz, My experience as researcher and author of a review article in The Journal Clinical Cardiology and Interventions has been very enriching and stimulating. The editorial team is excellent, performs its work with absolute responsibility and delivery. They are proactive, dynamic and receptive to all proposals. Supporting at all times the vast universe of authors who choose them as an option for publication. The team of review specialists, members of the editorial board, are brilliant professionals, with remarkable performance in medical research and scientific methodology. Together they form a frontline team that consolidates the JCCI as a magnificent option for the publication and review of high-level medical articles and broad collective interest. I am honored to be able to share my review article and open to receive all your comments.
“The peer review process of JPMHC is quick and effective. Authors are benefited by good and professional reviewers with huge experience in the field of psychology and mental health. The support from the editorial office is very professional. People to contact to are friendly and happy to help and assist any query authors might have. Quality of the Journal is scientific and publishes ground-breaking research on mental health that is useful for other professionals in the field”.
Dear editorial department: On behalf of our team, I hereby certify the reliability and superiority of the International Journal of Clinical Case Reports and Reviews in the peer review process, editorial support, and journal quality. Firstly, the peer review process of the International Journal of Clinical Case Reports and Reviews is rigorous, fair, transparent, fast, and of high quality. The editorial department invites experts from relevant fields as anonymous reviewers to review all submitted manuscripts. These experts have rich academic backgrounds and experience, and can accurately evaluate the academic quality, originality, and suitability of manuscripts. The editorial department is committed to ensuring the rigor of the peer review process, while also making every effort to ensure a fast review cycle to meet the needs of authors and the academic community. Secondly, the editorial team of the International Journal of Clinical Case Reports and Reviews is composed of a group of senior scholars and professionals with rich experience and professional knowledge in related fields. The editorial department is committed to assisting authors in improving their manuscripts, ensuring their academic accuracy, clarity, and completeness. Editors actively collaborate with authors, providing useful suggestions and feedback to promote the improvement and development of the manuscript. We believe that the support of the editorial department is one of the key factors in ensuring the quality of the journal. Finally, the International Journal of Clinical Case Reports and Reviews is renowned for its high- quality articles and strict academic standards. The editorial department is committed to publishing innovative and academically valuable research results to promote the development and progress of related fields. The International Journal of Clinical Case Reports and Reviews is reasonably priced and ensures excellent service and quality ratio, allowing authors to obtain high-level academic publishing opportunities in an affordable manner. I hereby solemnly declare that the International Journal of Clinical Case Reports and Reviews has a high level of credibility and superiority in terms of peer review process, editorial support, reasonable fees, and journal quality. Sincerely, Rui Tao.
Clinical Cardiology and Cardiovascular Interventions I testity the covering of the peer review process, support from the editorial office, and quality of the journal.
Clinical Cardiology and Cardiovascular Interventions, we deeply appreciate the interest shown in our work and its publication. It has been a true pleasure to collaborate with you. The peer review process, as well as the support provided by the editorial office, have been exceptional, and the quality of the journal is very high, which was a determining factor in our decision to publish with you.
The peer reviewers process is quick and effective, the supports from editorial office is excellent, the quality of journal is high. I would like to collabroate with Internatioanl journal of Clinical Case Reports and Reviews journal clinically in the future time.
Clinical Cardiology and Cardiovascular Interventions, I would like to express my sincerest gratitude for the trust placed in our team for the publication in your journal. It has been a true pleasure to collaborate with you on this project. I am pleased to inform you that both the peer review process and the attention from the editorial coordination have been excellent. Your team has worked with dedication and professionalism to ensure that your publication meets the highest standards of quality. We are confident that this collaboration will result in mutual success, and we are eager to see the fruits of this shared effort.
Dear Dr. Jessica Magne, Editorial Coordinator 0f Clinical Cardiology and Cardiovascular Interventions, I hope this message finds you well. I want to express my utmost gratitude for your excellent work and for the dedication and speed in the publication process of my article titled "Navigating Innovation: Qualitative Insights on Using Technology for Health Education in Acute Coronary Syndrome Patients." I am very satisfied with the peer review process, the support from the editorial office, and the quality of the journal. I hope we can maintain our scientific relationship in the long term.
Dear Monica Gissare, - Editorial Coordinator of Nutrition and Food Processing. ¨My testimony with you is truly professional, with a positive response regarding the follow-up of the article and its review, you took into account my qualities and the importance of the topic¨.
Dear Dr. Jessica Magne, Editorial Coordinator 0f Clinical Cardiology and Cardiovascular Interventions, The review process for the article “The Handling of Anti-aggregants and Anticoagulants in the Oncologic Heart Patient Submitted to Surgery” was extremely rigorous and detailed. From the initial submission to the final acceptance, the editorial team at the “Journal of Clinical Cardiology and Cardiovascular Interventions” demonstrated a high level of professionalism and dedication. The reviewers provided constructive and detailed feedback, which was essential for improving the quality of our work. Communication was always clear and efficient, ensuring that all our questions were promptly addressed. The quality of the “Journal of Clinical Cardiology and Cardiovascular Interventions” is undeniable. It is a peer-reviewed, open-access publication dedicated exclusively to disseminating high-quality research in the field of clinical cardiology and cardiovascular interventions. The journal's impact factor is currently under evaluation, and it is indexed in reputable databases, which further reinforces its credibility and relevance in the scientific field. I highly recommend this journal to researchers looking for a reputable platform to publish their studies.
Dear Editorial Coordinator of the Journal of Nutrition and Food Processing! "I would like to thank the Journal of Nutrition and Food Processing for including and publishing my article. The peer review process was very quick, movement and precise. The Editorial Board has done an extremely conscientious job with much help, valuable comments and advices. I find the journal very valuable from a professional point of view, thank you very much for allowing me to be part of it and I would like to participate in the future!”
Dealing with The Journal of Neurology and Neurological Surgery was very smooth and comprehensive. The office staff took time to address my needs and the response from editors and the office was prompt and fair. I certainly hope to publish with this journal again.Their professionalism is apparent and more than satisfactory. Susan Weiner