Prosthetic knees use various control mechanisms to mimic natural knee movement during walking. Single-axis knees function as a simple hinge and provide stability through manual locks. Polycentric knees have multiple rotation points and instant centers of rotation for improved stability. Mechanical friction knees resist bending through adjustable friction, while pneumatic and hydraulic knees use compressed air or fluid transfer between chambers to vary resistance based on knee angle and walking speed. Weight-activated stance control knees automatically lock to prevent buckling when weight is applied.
This document discusses spinal orthosis and cervical orthosis. It provides an overview of the principles and indications for orthotic devices. Specifically, it outlines the functions of orthosis in relieving pain, immobilizing joints, reducing weight bearing, preventing and correcting deformities, and improving function. It also describes different types of cervical orthosis including soft collars, Philadelphia collars, and halo vests. The key objectives of spinal orthosis are to control spinal position, apply corrective forces, and aid stability.
This document provides definitions and descriptions of various hip, knee, ankle, and foot orthoses. It describes a hip-knee-ankle-foot orthosis (HKAFO) as an orthosis that stabilizes or locks the hip, knee, and ankle. The typical HKAFO consists of two knee-ankle-foot orthoses linked above the hip with a pelvic band or lumbosacral orthosis. It also discusses indications, principles, components, and fabrication of HKAFOs as well as other orthoses like reciprocal gait orthoses and hip orthoses.
Lower limb orthoses assist with gait, reduce pain, decrease weight bearing, control movement, and minimize deformities. They include foot orthoses and ankle-foot orthoses. Foot orthoses affect ground forces and gait rotation, and are used to treat various foot conditions like pes planus, pes cavus, metatarsalgia, and heel pain. Ankle-foot orthoses control ankle motion and provide stability, and include metal and plastic designs with options for plantar stops, dorsiflexion stops, and dorsiflexion assists.
This document discusses transfemoral prostheses. It begins with an introduction to transfemoral amputation, which is the amputation of the leg between the knee and hip. It then covers the rehabilitation process for individuals with a transfemoral amputation, including exercises and management of the residual limb. Finally, it describes the components of transfemoral prostheses, including different socket designs, suspension methods, knee and foot options. The goal of rehabilitation and prosthetic training is to help individuals regain mobility and independence.
This document provides an overview of lower limb prosthetics. It defines prosthetics as devices that replace missing limbs and discusses their aims of restoring function and mobility. It describes the common levels of lower limb amputation as transtibial and transfemoral. The key components of a lower limb prosthesis are then outlined as the socket, suspension system, knee joint, shank/pylon, and foot/terminal device. Issues related to prosthesis use like skin problems, pain, and ineffective suspension are also summarized.
Lower Limb Orthotics - Dr Rajendra Sharmamrinal joshi
This document provides information on lower limb orthotics. It defines an orthosis and describes their clinical objectives in treating conditions like pain, deformities, abnormal range of motion, etc. It discusses different types of orthoses like foot, ankle-foot, knee-ankle-foot orthoses. Principles of bracing like distributing forces over large areas and applying forces to control joints are covered. Characteristics of an ideal orthosis in terms of function, comfort, cost are outlined. The document also discusses shoes, foot orthoses, ankle-foot orthoses made of plastic, metal and patellar tendon bearing designs.
This document provides guidance on prescribing wheelchairs. It outlines the parts of a wheelchair, important considerations in evaluating patients, and goals of prescription. A proper evaluation involves medical history, physical exam, and functional assessment. Prescriptions are developed using tools like the SEAT checklist to address safety, comfort, and accommodation of needs over time. The goals of prescription include normalization of tone, improved function and mobility, and increased comfort and skin integrity.
This document discusses spinal orthosis and cervical orthosis. It provides an overview of the principles and indications for orthotic devices. Specifically, it outlines the functions of orthosis in relieving pain, immobilizing joints, reducing weight bearing, preventing and correcting deformities, and improving function. It also describes different types of cervical orthosis including soft collars, Philadelphia collars, and halo vests. The key objectives of spinal orthosis are to control spinal position, apply corrective forces, and aid stability.
This document provides definitions and descriptions of various hip, knee, ankle, and foot orthoses. It describes a hip-knee-ankle-foot orthosis (HKAFO) as an orthosis that stabilizes or locks the hip, knee, and ankle. The typical HKAFO consists of two knee-ankle-foot orthoses linked above the hip with a pelvic band or lumbosacral orthosis. It also discusses indications, principles, components, and fabrication of HKAFOs as well as other orthoses like reciprocal gait orthoses and hip orthoses.
Lower limb orthoses assist with gait, reduce pain, decrease weight bearing, control movement, and minimize deformities. They include foot orthoses and ankle-foot orthoses. Foot orthoses affect ground forces and gait rotation, and are used to treat various foot conditions like pes planus, pes cavus, metatarsalgia, and heel pain. Ankle-foot orthoses control ankle motion and provide stability, and include metal and plastic designs with options for plantar stops, dorsiflexion stops, and dorsiflexion assists.
This document discusses transfemoral prostheses. It begins with an introduction to transfemoral amputation, which is the amputation of the leg between the knee and hip. It then covers the rehabilitation process for individuals with a transfemoral amputation, including exercises and management of the residual limb. Finally, it describes the components of transfemoral prostheses, including different socket designs, suspension methods, knee and foot options. The goal of rehabilitation and prosthetic training is to help individuals regain mobility and independence.
This document provides an overview of lower limb prosthetics. It defines prosthetics as devices that replace missing limbs and discusses their aims of restoring function and mobility. It describes the common levels of lower limb amputation as transtibial and transfemoral. The key components of a lower limb prosthesis are then outlined as the socket, suspension system, knee joint, shank/pylon, and foot/terminal device. Issues related to prosthesis use like skin problems, pain, and ineffective suspension are also summarized.
Lower Limb Orthotics - Dr Rajendra Sharmamrinal joshi
This document provides information on lower limb orthotics. It defines an orthosis and describes their clinical objectives in treating conditions like pain, deformities, abnormal range of motion, etc. It discusses different types of orthoses like foot, ankle-foot, knee-ankle-foot orthoses. Principles of bracing like distributing forces over large areas and applying forces to control joints are covered. Characteristics of an ideal orthosis in terms of function, comfort, cost are outlined. The document also discusses shoes, foot orthoses, ankle-foot orthoses made of plastic, metal and patellar tendon bearing designs.
This document provides guidance on prescribing wheelchairs. It outlines the parts of a wheelchair, important considerations in evaluating patients, and goals of prescription. A proper evaluation involves medical history, physical exam, and functional assessment. Prescriptions are developed using tools like the SEAT checklist to address safety, comfort, and accommodation of needs over time. The goals of prescription include normalization of tone, improved function and mobility, and increased comfort and skin integrity.
An Immediate Post operative Prosthesis (IPOP) or Immediate Post-surgical fitting is a device that is applied before or after wound closure that protects the suture site and allows limited weight bearing and gait training. It serves as a bridge between surgery and a definitive prosthesis. IPOPs can be custom fabricated or prefabricated and are commonly used at the transtibial and transradial levels. Advantages include reducing phantom limb pain and sensations, earlier weight bearing and rehabilitation, and shorter recovery times. Air splints are a type of non-custom IPOP that provide uniform pressure distribution, easy inspection of incision sites, and partial weight bearing ability.
A KAFO is a leg brace that controls knee and ankle movement. It is more energy intensive than FOs or AFOs due to compensatory movements needed to swing the leg. There are three main types - conventional metal, thermoplastic shell, and thermosetting shell. The document describes the components, designs, and joints of KAFOs including indications, advantages, and disadvantages of each. The goal is to select the appropriate KAFO design based on the individual needs of the patient.
This document discusses shoe modifications for lower extremity orthotics. It begins by outlining the purpose of shoes and modifications, which aim to restore normal gait and weight bearing. Key points include:
1) Shoe styles like the blucher and convalescent shoe provide easy access for patients with foot issues. Upperc like chukkas help prevent piston motion in patients with limited ankle motion.
2) Brace attachments must be rigidly attached to solid sole shoes to prevent undesirable ankle motions. Reinforcements may be needed to prevent shoe distortion from brace stresses.
3) Proper placement of steel shanks is important to allow natural dorsiflexion without depressing arches or shifting weight bearing
The document discusses upper limb orthosis, devices used to modify the structural and functional characteristics of the upper limb. It covers the objectives of upper limb orthosis including protection, correction, and assistance. It also discusses the classification, biomechanics, principles, and assessment of upper limb orthosis and provides descriptions and examples of specific upper limb orthoses including shoulder orthoses, arm slings, arm abduction orthoses, elbow/forearm/wrist orthoses, and elbow or wrist mobilization orthoses.
Rheumatoid arthritis (RA) is a chronic inflammatory disease that primarily involves the small joints of the hands and feet. The exact cause is unknown but autoimmunity is suspected. RA results in painful and deforming changes to the joints. It is classified based on the patient's functional ability. Hand deformities are common in RA and include swan neck, boutonniere, and Z-thumb deformities. Surgical treatment depends on the type and severity of deformity and aims to relieve pain and improve function.
Patellar tendinitis, also known as jumper's knee, is an overuse injury caused by repetitive stress on the patellar tendon from activities like jumping, running, and bending the knees. It causes pain below or around the kneecap. Treatment focuses on rest, ice, stretching, strengthening exercises, and anti-inflammatory medications. If conservative treatments are unsuccessful, corticosteroid injections or surgery may be considered to repair tendon damage. Complete recovery can take several months and requires adherence to a physical therapy program to restore mobility and strength.
This document discusses SLAP lesions of the shoulder. It defines SLAP lesions as injuries to the superior labrum. The etiology of SLAP lesions is controversial but may involve traction from the biceps tendon during throwing motions. People at risk include those with poor scapular control or tight posterior capsules. Physical exams do not conclusively diagnose SLAP lesions. Treatment involves a 3-phase rehabilitation program focusing on the kinetic chain, mobility, and strengthening. Core stability, scapular stabilization, and manual therapy techniques are emphasized. While surgery is an option, adaptive changes in throwers mean repairing anatomy may hinder performance. An integrated approach addressing the whole body is most effective for shoulder pain.
Orthosis are devices used to support weak joints and correct deformities. They work by applying three point pressure and distributing weight across a wide surface area. Common orthosis include ankle foot orthosis (AFO) which support the ankle and foot, knee ankle foot orthosis (KAFO) which stabilize the knee and lower leg, and hip knee ankle foot orthosis (HKAFO) which provide support from the hip to the foot. Orthosis are made of plastic or metal and their design depends on the joints needing support and the individual's condition.
presentation is about Orthosis and prosthesis. It gives Classification of Orthosis. It describes structure, function, Indication and uses of Orthosis. Also describes different types of Prostheses, their parts and function.
Recent Advances In Lower Limb ProsthesisAbey P Rajan
This document provides a review of literature on lower extremity amputation and prosthetics. It begins with an introduction that defines amputation and its most common causes. It then describes the different levels of lower limb amputation from partial foot to hip disarticulation. The document reviews the history and types of prosthetics for each level of amputation. It also discusses various prosthetic components like sockets, suspension systems, feet and knee units. Studies comparing outcomes of microprocessor prosthetics vs conventional designs are summarized. The review provides an overview of the state of knowledge on lower limb amputation and rehabilitation.
A complete description of the lower limb orthosis is available in the following presentation with an in depth understanding of the same.It covers the ankle foot orthosis,Knee orthosis the knee ankle foot orthosis and hip orthosis.
Prosthetic management of symes and partial foot amputationSmita Nayak
prosthetic management of partial foot and syme's amputation is a very challenging task. Now a days the availability of advanced technology some how fulfilling the need of the amputee but not the fully.
This document discusses spinal orthosis and cervical orthosis. It provides information on the principles and indications of orthotic devices. Some key points include: orthotic devices are prescribed to improve function, relieve pain, and prevent/correct deformities. Proper fitting is important for comfort. Orthoses can immobilize joints and reduce weight bearing to aid healing. Cervical orthoses specifically are used to limit neck movement and muscle spasm after injuries or surgeries. Common types of cervical orthoses include soft collars, Philadelphia orthosis, and halo vest.
The patellar tendon bearing prosthesis was invented in the 1950s as an improvement over the plug fit socket. It distributes pressure over specific areas of the residual limb that are better able to tolerate pressure, such as the patellar tendon, muscles, and bone. Areas with nerves, blood vessels, and less tissue are relieved of pressure. The prosthesis has a socket, foot assembly such as a SACH foot, shank to connect them, and a suspension like a strap to hold it in place. It provides control, weight bearing ability, and acceptance for amputees.
Over the past decade, technology and research have greatly expanded the functionality and aesthetics of prosthetic feet. Today, amputees have a wide array of feet from which to choose. Various models are designed for activities ranging from walking, dancing and running to cycling, golfing, swimming and even snow skiing.
Tans femoral Amputee : Prosthetics Knee Joints.pptxKezaiah S
Prosthetic knee joints are artificial devices designed to replace the function of a natural knee joint in individuals who have lost their knee joint due to injury, disease, or amputation.
Tans femoral Amputee : Prosthetics Knee Joints.pptxKezaiah S
Prosthetic knee joints are artificial devices designed to replace the function of a natural knee joint in individuals who have lost their knee joint due to injury, disease, or amputation.
An Immediate Post operative Prosthesis (IPOP) or Immediate Post-surgical fitting is a device that is applied before or after wound closure that protects the suture site and allows limited weight bearing and gait training. It serves as a bridge between surgery and a definitive prosthesis. IPOPs can be custom fabricated or prefabricated and are commonly used at the transtibial and transradial levels. Advantages include reducing phantom limb pain and sensations, earlier weight bearing and rehabilitation, and shorter recovery times. Air splints are a type of non-custom IPOP that provide uniform pressure distribution, easy inspection of incision sites, and partial weight bearing ability.
A KAFO is a leg brace that controls knee and ankle movement. It is more energy intensive than FOs or AFOs due to compensatory movements needed to swing the leg. There are three main types - conventional metal, thermoplastic shell, and thermosetting shell. The document describes the components, designs, and joints of KAFOs including indications, advantages, and disadvantages of each. The goal is to select the appropriate KAFO design based on the individual needs of the patient.
This document discusses shoe modifications for lower extremity orthotics. It begins by outlining the purpose of shoes and modifications, which aim to restore normal gait and weight bearing. Key points include:
1) Shoe styles like the blucher and convalescent shoe provide easy access for patients with foot issues. Upperc like chukkas help prevent piston motion in patients with limited ankle motion.
2) Brace attachments must be rigidly attached to solid sole shoes to prevent undesirable ankle motions. Reinforcements may be needed to prevent shoe distortion from brace stresses.
3) Proper placement of steel shanks is important to allow natural dorsiflexion without depressing arches or shifting weight bearing
The document discusses upper limb orthosis, devices used to modify the structural and functional characteristics of the upper limb. It covers the objectives of upper limb orthosis including protection, correction, and assistance. It also discusses the classification, biomechanics, principles, and assessment of upper limb orthosis and provides descriptions and examples of specific upper limb orthoses including shoulder orthoses, arm slings, arm abduction orthoses, elbow/forearm/wrist orthoses, and elbow or wrist mobilization orthoses.
Rheumatoid arthritis (RA) is a chronic inflammatory disease that primarily involves the small joints of the hands and feet. The exact cause is unknown but autoimmunity is suspected. RA results in painful and deforming changes to the joints. It is classified based on the patient's functional ability. Hand deformities are common in RA and include swan neck, boutonniere, and Z-thumb deformities. Surgical treatment depends on the type and severity of deformity and aims to relieve pain and improve function.
Patellar tendinitis, also known as jumper's knee, is an overuse injury caused by repetitive stress on the patellar tendon from activities like jumping, running, and bending the knees. It causes pain below or around the kneecap. Treatment focuses on rest, ice, stretching, strengthening exercises, and anti-inflammatory medications. If conservative treatments are unsuccessful, corticosteroid injections or surgery may be considered to repair tendon damage. Complete recovery can take several months and requires adherence to a physical therapy program to restore mobility and strength.
This document discusses SLAP lesions of the shoulder. It defines SLAP lesions as injuries to the superior labrum. The etiology of SLAP lesions is controversial but may involve traction from the biceps tendon during throwing motions. People at risk include those with poor scapular control or tight posterior capsules. Physical exams do not conclusively diagnose SLAP lesions. Treatment involves a 3-phase rehabilitation program focusing on the kinetic chain, mobility, and strengthening. Core stability, scapular stabilization, and manual therapy techniques are emphasized. While surgery is an option, adaptive changes in throwers mean repairing anatomy may hinder performance. An integrated approach addressing the whole body is most effective for shoulder pain.
Orthosis are devices used to support weak joints and correct deformities. They work by applying three point pressure and distributing weight across a wide surface area. Common orthosis include ankle foot orthosis (AFO) which support the ankle and foot, knee ankle foot orthosis (KAFO) which stabilize the knee and lower leg, and hip knee ankle foot orthosis (HKAFO) which provide support from the hip to the foot. Orthosis are made of plastic or metal and their design depends on the joints needing support and the individual's condition.
presentation is about Orthosis and prosthesis. It gives Classification of Orthosis. It describes structure, function, Indication and uses of Orthosis. Also describes different types of Prostheses, their parts and function.
Recent Advances In Lower Limb ProsthesisAbey P Rajan
This document provides a review of literature on lower extremity amputation and prosthetics. It begins with an introduction that defines amputation and its most common causes. It then describes the different levels of lower limb amputation from partial foot to hip disarticulation. The document reviews the history and types of prosthetics for each level of amputation. It also discusses various prosthetic components like sockets, suspension systems, feet and knee units. Studies comparing outcomes of microprocessor prosthetics vs conventional designs are summarized. The review provides an overview of the state of knowledge on lower limb amputation and rehabilitation.
A complete description of the lower limb orthosis is available in the following presentation with an in depth understanding of the same.It covers the ankle foot orthosis,Knee orthosis the knee ankle foot orthosis and hip orthosis.
Prosthetic management of symes and partial foot amputationSmita Nayak
prosthetic management of partial foot and syme's amputation is a very challenging task. Now a days the availability of advanced technology some how fulfilling the need of the amputee but not the fully.
This document discusses spinal orthosis and cervical orthosis. It provides information on the principles and indications of orthotic devices. Some key points include: orthotic devices are prescribed to improve function, relieve pain, and prevent/correct deformities. Proper fitting is important for comfort. Orthoses can immobilize joints and reduce weight bearing to aid healing. Cervical orthoses specifically are used to limit neck movement and muscle spasm after injuries or surgeries. Common types of cervical orthoses include soft collars, Philadelphia orthosis, and halo vest.
The patellar tendon bearing prosthesis was invented in the 1950s as an improvement over the plug fit socket. It distributes pressure over specific areas of the residual limb that are better able to tolerate pressure, such as the patellar tendon, muscles, and bone. Areas with nerves, blood vessels, and less tissue are relieved of pressure. The prosthesis has a socket, foot assembly such as a SACH foot, shank to connect them, and a suspension like a strap to hold it in place. It provides control, weight bearing ability, and acceptance for amputees.
Over the past decade, technology and research have greatly expanded the functionality and aesthetics of prosthetic feet. Today, amputees have a wide array of feet from which to choose. Various models are designed for activities ranging from walking, dancing and running to cycling, golfing, swimming and even snow skiing.
Tans femoral Amputee : Prosthetics Knee Joints.pptxKezaiah S
Prosthetic knee joints are artificial devices designed to replace the function of a natural knee joint in individuals who have lost their knee joint due to injury, disease, or amputation.
Tans femoral Amputee : Prosthetics Knee Joints.pptxKezaiah S
Prosthetic knee joints are artificial devices designed to replace the function of a natural knee joint in individuals who have lost their knee joint due to injury, disease, or amputation.
This document discusses different types of prosthetic knee joints, including mechanical single-axis and polycentric knees, and computerized knees that use microchips, hydraulics, or pneumatics to control motion. It describes the evolution of prosthetic knees from simple pendulums to advanced mechanisms with microprocessor control. Key factors in prescribing the appropriate knee include the user's ability to control stability, flex the knee in swing phase, and walk at different speeds.
A prosthesis is an artificial replacement for any part of the body that is missing. It is designed to replace the function and appearance of the missing limb as much as possible. Prostheses for lower and upper limb amputations are prescribed based on the level and cause of amputation. The main components of a prosthesis are the socket, suspension system, control system, and terminal device. The socket provides an intimate fit with the residual limb. Suspension systems like belts and harnesses help hold the prosthesis securely. Control systems can be body-powered using cables or externally powered using batteries. Terminal devices replace missing hands or feet. The goal is to restore ambulation and functional tasks using a prosthesis.
This document discusses lower extremity prostheses. It begins by defining prosthetics as the evaluation, fabrication and fitting of artificial limbs known as prostheses, which are devices used to replace or substitute parts of limbs. It then discusses the common causes of amputations, different levels of amputations, the aims of prostheses including restoring function and ambulation, components of prostheses including sockets, interfaces and suspension systems, and different types of prostheses for various levels of amputation such as transtibial and Syme's prostheses.
Prosthetic management of individuals with upper extremity
amputations presents all health professionals, including
prosthetists and therapists, with a set of unique challenges.
For those wearing an upper extremity prosthesis, the terminal
device (TD) of the prosthesis is not covered or obscured
by clothing in the same way that a lower extremity prosthesis
is “hidden” by pants, socks, and shoes. The person with
upper extremity amputation must cope with not only physical
appearance changes, but the loss of some of the most
complex movement patterns and functional activities of
the human body.
In addition, upper extremity limb loss deprives the patient
of an extensive and valuable system of tactile and proprioceptive
inputs that previously provided “feedback” to guide and
refine functional movement. Even the simplest tasks
related to grasp and release become challenging. The ability
to position the prosthetic limb segments in space, as well as
the ability to maintain advantageous postures needed to
manipulate objects, challenge the medical community to
continuously improve the functional and aesthetic outcomes
of prostheses for patients in this population.
The document discusses upper extremity prostheses. It describes different types of prostheses including passive prostheses for cosmesis, body-powered prostheses that use harness cables, and externally powered electric prostheses. It provides details on terminal devices (hands, hooks), wrist and elbow units, socket designs, and the rehabilitation process. The goals of prosthetic design are comfort, function matched to the user's needs and activities, durability, and cosmesis. Design considerations include the amputation level and residual limb.
disability is a physical or mental condition that limits a person’s movement , sense or activities.
It is an important public health problem especially in developing countries like India . Any form of disability cannot be fully restored but measures and efforts can be put in to improve the conditions.
prosthetic devices are an artificial device that replaces a missing body part which may be lost through trauma, diseases or congenital conditions.
Purpose- used to replace a missing limb to perform functional tasks.
The importance of Rehabilitation explains about the trends in development of prosthetic and orthotic devices and how, the technology can be used to improve the current devices in the market. Devices for mobility, Devices for visual impairment and hearing impairment and its uses are explained.
Prosthesis upper limb and lower limb.pptxBadalverma11
Physiotherapy- Complete details about prosthesis both upper and lower limb, and training and physiotherapy management #gait training #sports
Contents-
Introduction
Purpose
Components
Upper limb- above elbow And below elbow, socket, cable mechanism, elbow and wrist unit, hand/terminal device
Lower limb- above knee, below knee and syme prosthesis
Socket- quadrilateral, PTB
Knee and ankle unit
Foot
Physiotherapy management -
First therapy, muscle strengthening, mobility
Training of don and doff , care of. Stump and bandaging
Gait training and sports
@cpu
This document discusses treatment options and prosthetic management for different types of tibial deficiency based on the Jones and Kalamchi classifications. For complete tibial deficiency (Jones type 1a/Kalamchi I), knee disarticulation is indicated and the child is fit with an above-knee prosthesis by 4-6 weeks post-operatively. For partial tibial deficiency (Jones type 2/Kalamchi II), the non-functional foot is removed and later synostosis of the fibula to the proximal tibia is performed, with the child fit with a below-knee prosthesis. Prosthetic components like sockets, knees, shin components and feet are discussed for different tibial deficiency types and
Polio can cause muscle weakness and paralysis, especially in the legs. A modular knee ankle foot orthosis (KAFO) was designed with a spring cable placed above the knee to help lock and unlock the stance control knee joint. This allows patients to walk more naturally by providing stability during standing and swinging the leg freely during walking. Test results found patients could easily lock and unlock the KAFO and walk with better balance and load distribution through their joints.
Static elbow orthoses are used for short-term immobilization after injury or surgery, typically for 8-12 weeks. Dynamic elbow orthoses are used to minimize contractures or regain range of motion after immobilization. They apply constant low-load, long-duration stretching. Static progressive orthoses incorporate a manual tensioning unit to incrementally stretch or hold gains. Significant advantages of fracture orthoses over casts are improved hygiene and adjustability to changes in volume.
Suspension System for Transfemoral ProsthesisRohan Gupta
The document discusses various suspension systems used for transfemoral prostheses. It defines suspension systems as how the prosthesis is held to the residual limb. Eight different suspension systems are described in detail, including their advantages and disadvantages. The key systems discussed are cuffs/straps/belts, lanyards, self-suspending sockets, external sleeves, pin/lock, suction without liners, suction with liners, and vacuum-assisted suspension. Vacuum-assisted suspension creates a constant negative pressure for better suspension during volume changes but is more expensive due to mechanical components.
This document discusses upper limb prosthetics. It describes the characteristics of a successful prosthesis, considerations when choosing a prosthesis, reasons for upper limb amputations, amputation levels, types of prosthetics including cosmetic, functional, body-powered, externally powered and myoelectric prosthetics. It provides details on the typical components of an upper limb body-powered prosthesis including the socket, suspension, control cables, terminal devices and any intervening joint components. It outlines the timelines for amputation and prosthetic fitting.
The document proposes designs for a wrist aid and footplate attachment for a rowing ergometer to accommodate athletes with limited joint range of motion. The wrist aid is intended to reduce force on the wrist of an athlete with arthritis. It would consist of straps and a compression sleeve to distribute force to the forearm. The rotating footplate aims to increase stroke length for an athlete with ankle bone spurs by allowing 12 more degrees of rotation. Calculations of forces exerted on wrists and feet during rowing informed the design requirements. Preliminary testing showed the devices could withstand non-cyclic loads but more testing is needed to confirm performance during intense training.
This document discusses range of motion (ROM) exercises including self-assisted ROM, wand exercises, continuous passive motion (CPM), and ROM through functional patterns. Self-assisted ROM uses the uninvolved extremity to move the involved extremity and can be done manually, with equipment, or using reciprocal motion devices. Wand exercises provide guidance for shoulder and elbow ROM. CPM machines passively move a joint through a controlled ROM post-surgery to prevent stiffness and adhesions. Early ROM training focuses on functional patterns like eating, reaching, and dressing.
The document discusses prosthetic knee joints, classifying them based on axis type and control mechanisms. It describes single-axis knees that provide stability but lack swing phase control and polycentric multi-axis knees that more closely mimic natural knee motion. Control mechanisms include manual and automatic locking, hydraulic/pneumatic resistance, and microprocessor units that sense gait to adjust resistance for different surfaces.
Design and Development of a Wrist Exoskeleton for people post stroke copy.pptxRishintiranGovindara
This document summarizes a student's final year project on designing a wrist exoskeleton device for stroke rehabilitation using shape memory alloys. It introduces the topic, outlines the objectives to develop and test a prototype that provides wrist flexion and extension using SMA wires. A literature review compares existing devices and a methodology is proposed using AutoCAD, 3D printing, sensors and a microcontroller. Expected results are provided showing the relationship between temperature, deformation of SMA wires and degrees of wrist bending. The document aims to develop a device to improve range of motion for wrist rehabilitation post-stroke.
An orthosis is an external device that is applied to the body to improve function, provide support, reduce pain, correct deformities, and prevent progression of fixed deformities. Lower limb orthoses include foot orthoses, ankle-foot orthoses, knee orthoses, knee-ankle-foot orthoses, and hip-knee-ankle-foot orthoses. The goals of lower limb orthoses are to maintain or correct body segment alignment, assist or resist joint motion, provide axial loading and relieve distal weight bearing forces, and protect against injury. Orthoses can be static devices that hold body parts in position or dynamic devices that facilitate motion.
Similar to Rohan_Gupta_Control Mechanism of Prosthetic Knee Joints_Assignment.pptx (20)
The document provides an overview of a presentation on cerebral palsy. It defines cerebral palsy as a non-progressive brain injury leading to motor dysfunction in infants. The main risk factors are prenatal, perinatal, and postnatal issues. Symptoms vary in severity but can include difficulties with movement, muscle tone abnormalities, seizures, and intellectual impairments. There are several types of cerebral palsy defined by the parts of the brain affected. Diagnosis involves parental observation of developmental delays, clinical examination of motor skills, review of medical history, and ruling out other potential causes.
Rohan_Gupta_Orthotic Management of Physioneurological AFO_Assignment.pptxRohan Gupta
This document describes an ankle-foot orthosis (AFO) designed based on neurodevelopmental concepts to address gait concerns in neurologically impaired patients. The AFO incorporates biomechanical and neurophysiological forces including a three-point pressure system to control calcaneal varus, forces on the medial and lateral aspects of the foot to facilitate reflexes, and a metatarsal arch to inhibit the toe grasp reflex. It is prescribed for patients with minimal to moderate spasticity to improve ankle positioning and weight bearing during gait.
The document discusses various types of abnormal or pathological human gaits caused by different medical conditions. It describes gaits associated with pain, neurological disorders, muscle weakness or paralysis, joint limitations, deformities, and leg length discrepancies. Specific gaits are defined such as antalgic, psoatic, gluteus maximus, quadriceps, hemiplegic, scissoring, ataxic, and foot drop gaits. Causes and compensatory mechanisms for each gait type are explained.
The document discusses muscle tone and how it relates to movement and rehabilitation. It summarizes that tone assists with balance and posture development in infants and diminishes as higher movement skills develop. For neurologically impaired patients, high muscle tone presents challenges for rehabilitation professionals. The document then discusses various tone-reducing techniques that have been used in casts and orthoses, including applying pressure to specific areas of the foot or leg to inhibit reflexes. It provides examples of ankle-foot orthosis designs that aim to reduce tone through biomechanical alignment and pressure on muscle insertions.
Prosthetic Management of Different Types of Partial Foot AmputationRohan Gupta
This document discusses different types of partial foot amputations and their prosthetic management. It describes 7 types of partial foot amputations ranging from toe amputations to Syme's amputation, which is an ankle disarticulation. For each amputation type, it discusses the bones and joints involved, potential complications, prosthetic goals in managing the condition, and examples of prosthetic solutions used. The document provides an overview of evaluating each partial foot amputation case and designing an appropriate prosthesis to address the patient's functional requirements and minimize complications.
This document discusses longitudinal deficiency of the femoral partial (LDFP), which is a congenital absence of part or all of the femur associated with other lower limb abnormalities. It can be unilateral or bilateral. The etiology is unknown but may involve vascular or infection issues. Clinical presentation includes a shortened lower limb, thickened thigh, foot deformities, and abnormal limb positioning. Treatment options include surgical procedures like ankle disarticulation or femoral-pelvic fusion, or non-surgical approaches like prosthetics tailored to the specific classification and severity of the LDFP. Prosthetic fittings aim to address limb length discrepancy, joint instability, muscle inadequacy, and functional needs.
Role of Biomedical Technologies in Prosthetics and OrthoticsRohan Gupta
The document discusses biomedical technologies that help people who are unable to stand, walk, run, or hold objects on their own. It outlines technologies like prosthetic limbs, orthoses, functional electrical stimulation, microprocessor-controlled limbs, and powered wheelchairs that improve mobility and independence. Emerging areas discussed include osseointegration, artificial intelligence, thought-controlled prosthetics, 3D printing, soft wearable robots, and biosensors that will continue to advance assistive technologies. The author concludes that such advances in prosthetics and orthotics not only help individuals but also strengthen society by enabling more people to contribute.
ESMS (Ergonomically Suited Molded Seat Seat For Scoliosis)Rohan Gupta
This presentation was published in January 2018 during the National Conference of OPAI. This presentation includes a research work for a 15 yr old fixed scoliotic patient to cure and atleast prevent from further progression of the curve by providing him a customised molded seat acc to the nature of his deformity . We name this as ESMS.
Leading the world towrads robotic function in hand restorationRohan Gupta
This presentation was published in March 2017 during National Conference of Orthotic Prosthetic Association of India. This presentation includes the recent robotic research trend present in the field for the persons who are less muscle power, Hemiplegics etc.
TEST BANK For Accounting Information Systems, 3rd Edition by Vernon Richardso...rightmanforbloodline
TEST BANK For Accounting Information Systems, 3rd Edition by Vernon Richardson, Verified Chapters 1 - 18, Complete Newest Version
TEST BANK For Accounting Information Systems, 3rd Edition by Vernon Richardson, Verified Chapters 1 - 18, Complete Newest Version
TEST BANK For Accounting Information Systems, 3rd Edition by Vernon Richardson, Verified Chapters 1 - 18, Complete Newest Version
Michigan HealthTech Market Map 2024. Includes 7 categories: Policy Makers, Academic Innovation Centers, Digital Health Providers, Healthcare Providers, Payers / Insurance, Device Companies, Life Science Companies, Innovation Accelerators. Developed by the Michigan-Israel Business Accelerator
Can Allopathy and Homeopathy Be Used Together in India.pdfDharma Homoeopathy
This article explores the potential for combining allopathy and homeopathy in India, examining the benefits, challenges, and the emerging field of integrative medicine.
Healthy Eating Habits:
Understanding Nutrition Labels: Teaches how to read and interpret food labels, focusing on serving sizes, calorie intake, and nutrients to limit or include.
Tips for Healthy Eating: Offers practical advice such as incorporating a variety of foods, practicing moderation, staying hydrated, and eating mindfully.
Benefits of Regular Exercise:
Physical Benefits: Discusses how exercise aids in weight management, muscle and bone health, cardiovascular health, and flexibility.
Mental Benefits: Explains the psychological advantages, including stress reduction, improved mood, and better sleep.
Tips for Staying Active:
Encourages consistency, variety in exercises, setting realistic goals, and finding enjoyable activities to maintain motivation.
Maintaining a Balanced Lifestyle:
Integrating Nutrition and Exercise: Suggests meal planning and incorporating physical activity into daily routines.
Monitoring Progress: Recommends tracking food intake and exercise, regular health check-ups, and provides tips for achieving balance, such as getting sufficient sleep, managing stress, and staying socially active.
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Gemma Wean- Nutritional solution for Artemiasmuskaan0008
GEMMA Wean is a high end larval co-feeding and weaning diet aimed at Artemia optimisation and is fortified with a high level of proteins and phospholipids. GEMMA Wean provides the early weaned juveniles with dedicated fish nutrition and is an ideal follow on from GEMMA Micro or Artemia.
GEMMA Wean has an optimised nutritional balance and physical quality so that it flows more freely and spreads readily on the water surface. The balance of phospholipid classes to- gether with the production technology based on a low temperature extrusion process improve the physical aspect of the pellets while still retaining the high phospholipid content.
GEMMA Wean is available in 0.1mm, 0.2mm and 0.3mm. There is also a 0.5mm micro-pellet, GEMMA Wean Diamond, which covers the early nursery stage from post-weaning to pre-growing.
This particular slides consist of- what is Pneumothorax,what are it's causes and it's effect on body, risk factors, symptoms,complications, diagnosis and role of physiotherapy in it.
This slide is very helpful for physiotherapy students and also for other medical and healthcare students.
Here is a summary of Pneumothorax:
Pneumothorax, also known as a collapsed lung, is a condition that occurs when air leaks into the space between the lung and chest wall. This air buildup puts pressure on the lung, preventing it from expanding fully when you breathe. A pneumothorax can cause a complete or partial collapse of the lung.
Joker Wigs has been a one-stop-shop for hair products for over 26 years. We provide high-quality hair wigs, hair extensions, hair toppers, hair patch, and more for both men and women.
Let's Talk About It: Breast Cancer (What is Mindset and Does it Really Matter?)bkling
Your mindset is the way you make sense of the world around you. This lens influences the way you think, the way you feel, and how you might behave in certain situations. Let's talk about mindset myths that can get us into trouble and ways to cultivate a mindset to support your cancer survivorship in authentic ways. Let’s Talk About It!
About this webinar: This talk will introduce what cancer rehabilitation is, where it fits into the cancer trajectory, and who can benefit from it. In addition, the current landscape of cancer rehabilitation in Canada will be discussed and the need for advocacy to increase access to this essential component of cancer care.
DECODING THE RISKS - ALCOHOL, TOBACCO & DRUGS.pdfDr Rachana Gujar
Introduction: Substance use education is crucial due to its prevalence and societal impact.
Alcohol Use: Immediate and long-term risks include impaired judgment, health issues, and social consequences.
Tobacco Use: Immediate effects include increased heart rate, while long-term risks encompass cancer and heart disease.
Drug Use: Risks vary depending on the drug type, including health and psychological implications.
Prevention Strategies: Education, healthy coping mechanisms, community support, and policies are vital in preventing substance use.
Harm Reduction Strategies: Safe use practices, medication-assisted treatment, and naloxone availability aim to reduce harm.
Seeking Help for Addiction: Recognizing signs, available treatments, support systems, and resources are essential for recovery.
Personal Stories: Real stories of recovery emphasize hope and resilience.
Interactive Q&A: Engage the audience and encourage discussion.
Conclusion: Recap key points and emphasize the importance of awareness, prevention, and seeking help.
Resources: Provide contact information and links for further support.
This particular slides consist of- what is hypotension,what are it's causes and it's effect on body, risk factors, symptoms,complications, diagnosis and role of physiotherapy in it.
This slide is very helpful for physiotherapy students and also for other medical and healthcare students.
Here is the summary of hypotension:
Hypotension, or low blood pressure, is when the pressure of blood circulating in the body is lower than normal or expected. It's only a problem if it negatively impacts the body and causes symptoms. Normal blood pressure is usually between 90/60 mmHg and 120/80 mmHg, but pressures below 90/60 are generally considered hypotensive.
MBC Support Group for Black Women – Insights in Genetic Testing.pdfbkling
Christina Spears, breast cancer genetic counselor at the Ohio State University Comprehensive Cancer Center, joined us for the MBC Support Group for Black Women to discuss the importance of genetic testing in communities of color and answer pressing questions.
2. What are Prosthetic Knees?
• Prosthetic knees are designed to mimic the bending (flexion) and swinging
(extension) of the anatomical knee joint as a patient walks. From advanced
computer controlled components to simple locking joints, the prosthetic
knee works together with the prosthetic foot and socket to achieve a smooth gait
pattern.
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3. Introduction
• Prosthetic knees can be divided into Mechanical or Computerized.
• Mechanical knees can then be subdivided into single-axis and
multiaxis/polycentric knees.
• All prosthetic knee require some sort of stability mechanism, this can be manual
or a weight-activated locking system.
• They also require a way to control the flexion and extension motion, this can be
done by friction or a hydraulic/pneumatic control.
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4. What does Mechanism means?
• “A system of parts working together in a machine or an object”
• In our field, the Prosthetic Knee joint is a Machine or an object which is working
with the help of different parts working together inside the prosthetic knee joint.
• “A mechanism is a device that transforms input forces and movement into a
desired set of output forces and movement. Mechanisms generally consist of
moving components.”
• In case of Prosthetic Knee, the movement of different parts inside the joint
results in or mimics the natural knee movements like flexion and extension.
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5. 1. Single-Axis Knees – Control Mechanism
• This is a Simple Hinge type knee.
• During the flexion/extension these articulations execute a simple rotation around the
knee axis.
• They are of simple design and their easy alignment responds to the rules of
mechanics.
• There are exoskeletal and endoskeletal knees, both versions can have manual or
automatic blocking of the flexion to be used in users with poor muscle power.
• The knees without blocking can be used for regular prosthetic fitting of amputees
with adequate muscle control and/or in situations of limited economic resources.
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7. Disadvantages
• Due to the simplicity the individual has to use their own muscle power in the
limb to keep the knee stable with heel contact and standing.
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8. Additional Component Benefit
• A manual lock can be added to give more stability in standing.
• A constant friction control can also be added which will prevent the leg from
swinging through very quickly.
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10. Rohan Gupta, MPO 1st Year, 3rd Batch
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Schematic
diagram of
Single Axis Knee
Joint.
11. 2. Polycentric Knees – Control Mechanism
• This knee has multiple axes of rotation.
• Polycentric knees can be four bar knees (4 axes of rotation) or seven bar knees
(seven axes of rotation).
• Knees of the most frequent use are of 4 axes (or 4 bars). Without giving
importance to the number of axes, the knees of poly-axial design have one thing
in common - the Instant Centre of Rotation (ICR) is situated much higher and
posterior than the mechanical axes when the knee is in extension.
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12. • To localize the ICR of a polycentric knee, we need to extend virtually the center
lines of the lateral bars towards proximal - the intersection of those lines will
indicate the ICR.
• This causes a high level of stability in the knee against involuntary flexion
during the heel strike. Standard polycentric knees have a single walking speed
but when a manufacturer includes pneumatic or hydraulic features the patient
will be able to vary their walking speed.
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13. Advantages
• It is very versatile in terms of stability and get be adjusted to be extremely stable
when the patient goes into stance phase, but in the same time allow an easy
swing and allows sitting down with a bent knee.
• Due to the multiple axes and the ICR, the prosthetic length "shortens" at the start
of toe-off and will allow for foot clearance.
• It is suitable for patients with the potential to be independent with the prosthesis
in their home and community as well as the more active person
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14. Disadvantages
• It is heavier than a single axis knee.
• More parts that need servicing.
• Most polycentric knees do not have stance flexion resistance and therefore
cannot yield during sitting, ramps, or stairs.
• A person with a knee that is not controlled by a microprocessor, needs to actively
generate a knee extension moment in the stance phase to prevent the knee from
buckling and cause the person to fall down.
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18. 3. Manual Locking Knees – Control Mechanism
• The manual locking knee is the most stable knee used in prosthetics.
• The manual locking knee is locked stiff at the knee when in use.
• The knee is locked during gait and the patient releases the lock mechanism in
order to sit down.
• Manual locking knees are primarily used with patients who have very short
residual limbs and/or poor hip strength and are unable to control the knee.
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19. • The knee will not bend until a release mechanism is operated to free the knee
lock (e.g. when sitting). This system makes the knee extremely safe.
• These types of knee are best suited to users with weak musculature or balance
issues. Occasionally they are used locked in the early stages of rehabilitation
with a view to unlocking them as the user progresses through therapy and
becomes more confident and able.
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20. Advantages
• This will allows for automatic locking of the knee with weight bearing, but the
patient can choose to manually lock the knee.
• This is especially for people who need extra security to keep the knee from
buckling in standing or with heel contact or when walking on uneven terrain.
• The indication for this type of knee is usually for K1 ambulators or debilitated
individuals who cannot voluntarily control their prosthetic knee.
• Can be made very lightweight.
• Usually used by amputees who are weak, unstable or unwell.
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21. Disadvantages
• The patient will need circumduct or hip hitch to allow for foot clearance when
the knee is locked during gait.
• May be difficult to unlock when weight is being taken through the knee or if the
user has insufficient hand control or strength.
• Stiff legged gait requires higher energy input.
• Asymmetrical gait.
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24. 4. Mechanical Friction Control Knees – Control
Mechanism
• Mechanical friction knees are lightweight and relatively inexpensive due to their
simplicity.
• The friction (resistance to bending) in the knee joint is typically adjusted by
tightening a screw or bolt. The same amount of friction is applied to the knee
regardless of whether it is flexing or extending.
• A spring is often used to overcome some of the friction when the knee extends
(straighten). This speeds up the knee in the swing phase of gait.
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25. Advantages
• Simplicity
• Durable & robust
• Can be made lighter and smaller.
• May be used over one axis of rotation (monocentric knees) or multiple axes
(polycentric knees).
• Inexpensive
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26. Disadvantages
• Friction reduces with wear & may need frequent adjustment.
• Constant friction design does not adapt to different walking speeds.
• May become noisy when wearing.
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28. 5. Constant Friction Control Knees – Control
Mechanism
• This system uses constant pressure against a rotating surface to resist knee
flexion.
• The amount of pressure is set by the Prosthetist and should not be altered by the
user.
• External spring(s) may be used to assist the knee to straighten faster than it
bends.
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29. Advanatages
• Simple
• Lightweight
• Dependable
• Can be found in both monocentric (single axis) and polycentric (multi axial)
knees.
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30. Disadvantages
• Can only be adjusted to one walking speed. Other speeds will have
compromised gait.
• Requires accurate adjustment by trained practitioner.
• Will require periodic adjustment to remain effective
• Knee becomes less stable as the knee wears (monocentric design).
• Becomes less efficient the more the knee bends.
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32. 6. Variable Friction Control Knees – Control
Mechanism
• Variable friction utilizes a fluid control system (hydraulic or pneumatic) to
control the amount resistance to knee bend.
• As knee bend increases, resistance increases and vice versa.
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33. Advantages
• Progressive resistance as knee bends.
• Can be found in both monocentric (single axis) and polycentric (multi axial)
knees.
• More natural gait.
• Can be adjusted to allow for a range of cadences.
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34. Disadvantages
• Can be expensive.
• Heavier and more complex than other systems.
• Requires accurate adjustment by trained practitioner.
• May require periodic adjustment.
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36. 7. Weight Activated Stance Control Knees –
Control Mechanism
• These knees are also called "safety knees“
• There is a constant friction system in the knee, which means it will apply a
braking force as the patient puts weight on the prosthesis, to prevent the knee
from buckling.
• The rest of the time the knee will swing freely, until the weight is applied to it.
• Knees with a weight activated stance control feature a built-in braking or locking
mechanism which is activated by the user’s bodyweight.
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37. • When the mechanism is engaged it either exerts pressure on the knee
components to restrict flexion (monocentric design) or alters the geometry to
make the knee less prone to flexion (polycentric design).
• While weight is directed through the knee and heel the brake is active. De-
weighting the knee releases the brake mechanism.
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38. Advantages
• Very stable knee.
• Prescribed for first time prosthetic users who need the stability especially in the
older or less active population but are still able to exert some control over the
knee. Or a person who fatigues quickly after just a few steps.
• This is especially valuable for the patient who forgets that they should not put
their weight on a partially bent knee, the friction in the knee will brake if this
happens and prevent the knee from collapsing into flexion.
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39. • Can be found in monocentric (single axis) style knees using either friction,
hydraulic or pneumatic systems.
• Featured in all polycentric knees with more than four centers of rotation.
• Enhanced stability at heel strike.
• Often an excellent choice for a primary amputee’s first prosthesis or for less
active amputees.
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40. Disadvantages
• When sitting down the patient will have to take the weight off the leg to allow it
to bend, this means that they will not be able to use the prosthetic side in the
sitting motion.
• The patient will also need to take the weight off the leg before the knee will
bend, this means that the normal knee flexion at toe off will not happen.
• Due to the friction in the knee the patient will also walk slower and take smaller
steps.
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41. • Requires accurate adjustment by a knowledgeable practitioner to ensure the lock
is effective.
• May require frequent adjustment (a poorly adjusted lock can be ineffective).
• User’s weight must be lifted off the prosthesis to unlock the knee (e.g. when
sitting).
• Steeper learning curve.
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43. 8. Pneumatic (Air) Control Knees – Control
Mechanism
• Prosthetic knee joints can be classified by the way that the flexion and extension
(bending and straightening) of the knee joint is regulated.
• This is known as the control mechanism.
• Pistons move through the control medium as the knee bends and extends.
• As the pistons move, control valves provide varying degrees of resistance
depending on the angle of the knee.
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44. • These systems allow a different stiffness during different phases of gait.
• The result allows the user to walk more comfortably at different speeds.
• Pneumatic (air) controlled knees have inner chambers which house a sliding
piston.
• The piston seals against the side of the chamber much like a bicycle pump.
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45. • As the piston moves, air is compressed by it, regulating the pressure against the
bending and straightening moments of the knee.
• The pressure differential allows the user to walk more comfortably at different
speeds.
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46. Advantages
• May be used over one axis of rotation (monocentric knees) or multiple axes
(polycentric knees).
• Efficient use of air compression lowers energy use.
• Provides better swing control than constant friction systems.
• Lighter than comparable hydraulic units.
• Generally lighter and less expensive that hydraulic knees.
• Allows variable walking speeds.
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47. • The resistance in the knee will allow the individual to climb down step over step
when walking down stairs, when weight is kept on the leg before and during the
motion.
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48. Disadvantages
• Piston seals are prone to wear.
• Less effective than hydraulic systems.
• Can produce heat when actively worked for long periods.
• Slightly heavier and more expensive than mechanical friction knees.
• Complex.
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50. 9. Hydraulic (Fluid) Control Knees – Control
Mechanism
• Prosthetic knee joints can be classified by the way that the flexion and extension
(bending and straightening) of the knee joint is regulated.
• Hydraulic (fluid) controlled knees have fluid filled inner chambers which house
a sliding piston.
• The piston seals against the side of the chamber much like a bicycle pump.
• As the piston moves, liquid (usually silicone oil) is transferred from one chamber
to another
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51. • The flow of fluid is regulated by control valves which can be adjusted to
moderate the bending and straightening resistance of the knee.
• The movement of fluid allows the user to walk more comfortably at different
speeds.
• As the pistons move, control valves provide varying degrees of resistance
depending on the angle of the knee.
• These systems allow a different stiffness during different phases of gait.
• The result allows the user to walk more comfortably at different speeds.
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52. Advantages
• May be used over one axis of rotation (monocentric knees) or multiple axes
(polycentric knees).
• Accurately mimics anatomical knee function.
• Provides better swing control and stability than constant friction or pneumatic
systems.
• Generally lighter and less expensive that microprocessor knees.
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53. • Allows more variation walking speeds than pneumatic units due to the fine
control afforded by the valves.
• Weight can be kept on the prosthetic leg when sitting down and the knee will
assist the individual to sit down.
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54. Disadvantages
• Piston seals are prone to wear.
• Can produce heat when actively worked for long periods.
• Heavier and more expensive than mechanical friction knees.
• Require more accuracy when being adjusted.
• More expensive than pneumatic or mechanical friction systems.
• Complex.
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56. 10. Computerised or Microprocessor Control
Knees – Control Mechanism
• These knees have a microprocessor that receives feedback from sensors located
inside the knee joint and/ or the foot.
• The data from the sensors are used to adjust the knee flexion and extension
range and speed to match what the individual requires at that moment in time.
• It can be explained as an "enhanced hydraulic system" where the computer is
controlling the opening and closing of the valves to allow the flow of hydraulic
fluid within the unit.
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57. • A typical microprocessor knee has a hydraulic actuator and a powered knee has
a motor actuator.
• In a motor-powered knee, knee extension is 'powered' for standing up from
sitting and controlled resistance is provided when sitting down.
• It provides active flexion and extension during gait.
• Symmetrical weight distribution and natural gait.
• Computerised knees feature an on-board micro-processor which receives
feedback from sensors inside the joint and foot.
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58. • The micro-processor uses the received data to constantly adjust the knee in real time
to match the user’s walking characteristics.
• In this respect they are type of enhanced hydraulic system where the computer
operates the control valves in the knee to restrict or allow the flow of hydraulic fluid.
• Micro-processor knees can adjust to different walking speeds, terrain and situations
and may also exhibit ‘stumble recovery’ features.
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59. Advantages
• Microprocessor knee lowers the amount and effort that an individual needs for
walking.
• More natural gait.
• The knee is able to quickly adapt to accommodate different walking speeds,
changing environment, or for specific situations.
• Some knees also have a stumble recovery to prevent the individual from falling.
• Can use a mobile device or computer to adjust settings.
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60. • Allows descending stairs step over step.
• The individual will be able to use the prosthetic side when sitting down or
standing up.
• Some knees offer stumble recovery.
• If the knee is able to adjust automatically according to the load the patient is
carrying (like adding a hiking pack or carrying a child), then it will reduced the
perceived exertion of the person and reduce the adaptive long stance on the
sound limb
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61. • Can have different walking/ activity modes.
• Once learned, it takes less cognitive effort.
• Superior control on uneven surfaces& ramps.
• The ability to descend stairs step over step.
• Supports weight bearing in stand to sit transition.
• Powers down safely and gracefully.
• Ability to adjust to different cadences.
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62. Disadvantages
• Cost - very expensive.
• The battery needs to charge.
• Weight is more than other knees.
• Cosmesis may be difficult.
• Specific foot selection.
• Can be damaged by environmental conditions (water, heat, cold, etc), kneeling
etc.
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63. • Initial steep learning curve and commitment to gait re-education.
• Regular servicing.
• Does not pair well with full length cosmetic covers.
• Sensitive to environmental conditions (dust, vibration, salt or fresh water,
chemicals, excess heat or cold, strong magnetic fields).
• For established amputees: requires significant commitment to gait re-education.
• May require trained & certified practitioner to make adjustments.
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