Amputees with lower limb loss need special care during daily life activities to make the movement natural as before amputation. No such work exists covering the main aspects from causes of amputation to the psycho-social impact of the amputees after using the prosthetic device. This review presents for lower limb prosthesis; the study of lower limb amputation, design & development, control strategies & machine learning algorithms, the psycho-social impact of prosthetic users, and design trends in patents. Research articles, review papers, magazines, letters, study reports, surveys, and patents, etc. have been used as sources for this review. Traumatic injuries and different diseases have been found as common causes of amputation. Design & development section illustrates design mechanisms, the categories of passive, active, & semi-active prostheses, an overview of a subset of commercially available prosthetic devices, and 3D printing of the accessories. The control section provides information about control techniques, sensors used, machine learning algorithms, and their key outcomes. Quality of life, phantom limb pain, and psycho-social impact of prosthetic users have been summarized for different countries that are believed to attract the interest of the readers. We have also developed an open-source database “FAKH-50” for patents to emphasize the design trends and advancements in lower limb prostheses from 1970 to 2020. Overall trend analysis determined is in the descending order as the knee (48%) > ankle (28%) > foot (22%) > hip (2%) patents in the current version of our database. The forthcoming section highlights the challenges and prospects of the domain. A mutual observation demands the design of a bio-compatible, lightweight, and economic prosthesis to track the normal human gait by eliminating phantom limb pain. This will empower the amputees to live a quality life in society. This work may be beneficial for researchers, technicians, clinicians, and amputees.

中文翻译：

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下肢假肢的进展、趋势及未来展望


下肢丧失的截肢者在日常生活活动中需要特别护理，以使动作像截肢前一样自然。目前还没有这样的工作涵盖从截肢原因到截肢者使用假肢装置后的心理社会影响等主要方面。这篇综述介绍了下肢假肢；研究下肢截肢、设计和开发、控制策略和机器学习算法、假肢使用者的心理社会影响以及专利设计趋势。研究文章、评论论文、杂志、信件、研究报告、调查和专利等均被用作本评论的来源。外伤和不同的疾病已被发现是截肢的常见原因。设计和开发部分阐述了设计机制、被动、主动和半主动假肢的类别、市售假肢装置子集的概述以及配件的 3D 打印。控制部分提供有关控制技术、使用的传感器、机器学习算法及其关键结果的信息。不同国家的假肢使用者的生活质量、幻肢痛和心理社会影响进行了总结，相信会引起读者的兴趣。我们还开发了一个开源专利数据库“FAKH-50”，强调1970年至2020年下肢假肢的设计趋势和进步。总体趋势分析确定，按降序排列为膝盖（48%）>脚踝 (28%) > 足部 (22%) > 臀部 (2%) 我们数据库当前版本中的专利。下一部分将重点介绍该领域的挑战和前景。 相互观察需要设计一种生物相容、轻便且经济的假肢，通过消除幻肢痛来跟踪正常的人类步态。这将使截肢者能够在社会上过上优质的生活。这项工作可能对研究人员、技术人员、临床医生和截肢者有益。