British Modular Lower Limbs System (1974)

there are over 60,000 lower limb amputees in Great Britain over 4,000 new patients are seen by limb fitting centers each year and this number is increasing this man is a bilateral amputee and like the others you'll see in this film is fitted with a new type of artificial leg which is of modular construction the leg has been developed by the artificial limb industry to give performance at least as good as there is a traditional construction to give amputees as much freedom of movement as possible and at the same time to be assembled quickly and easily by the use of pre-manufactured standard interchangeable component parts this facility enables a much quicker delivery of the finished limb to the amputee with repairs easily carried out by replacement confidence in the prosthesis is influenced by its function and cosmetic appearance amputation in this case was well about the right knee these 12 people aged between 13 and 58 are all wearing hayver above or below the knee modular mix the length of time since they were first fitted varies between 1 and 3 years their performance can be gauged by watching the amount of ramp and steps and complete the more difficult task of going down steps traditional artificial legs have become sophisticated but individual construction prevents the shortening of delivery times and the time required for repair or adjustment an important advantage of the modular leg is that components can be held and assembled at local limb centers as would be expected the below-knee amputee can negotiate the obstacle more easily the first stage in limb fitting is stumped measurement for the prosthetist the main objective is to determine the size and shape of the socket which is custom-made for each patient stumped the doctor would be more concerned with determining stamp function than the general physical condition of the patient sockets vary in material and method of manufacture wood is often preferred in humid conditions locked leather is malleable absorbs perspiration and permits ventilation metal is rigid and light but is time-consuming to make fiberglass cannot be adjusted but is light sufficiently strong and rigid whatever the socket the modular leg can accommodate it the order of assembly onto the chosen socket at the top of the display is now demonstrated first the three struts are shaped to the socket and finally secured by rivets a metal alignment cap follows also fitted by rivets an alignment device is secured by a single high tensile boat with nut and washer beneath this the selected knee mechanism is similarly attached the thigh covering made of plastic foam can now be added next the knee cover a metal cradle follows and inside this goes a pneumatic swing phase control the mechanism which controls extension and flexion of knee movement the anodized shin tube comes in various sizes and is matched to give the correct knee height of the patient special bonding and two fixing pins secure it to the cradle likewise the ankle component next foot now to complete the cosmesis comes the foam for the shin covered by a plastic skin and finally the thigh skin so now the leg is complete in size shape color and texture in practice the assembly is carried out in two phases the first phase would be followed by walking trials for demonstration purposes this leg has been assembled considerably out of alignment adjustments can be easily made to make angular collection the upper of two locking nuts is slackened further possible adjustments are shown with this marked assembly rotation above the knee mechanism is the second nut which when slackened allows anterior and posterior medial and lateral positioning when both nuts have been tightened walking trials continue until performance and leg matching are optimized this trial and error facility could be quickly completed at a day visit and avoids the usual delay for traditional limbs to be ordered this patient's gait is now correct adjustment to the below knee leg can be similarly carried out walking trials again confirm the results walking trials are followed by completing assembly and cosmesis here the thigh has been firmed in situ and is being shaped after shaping a plastic skin is used to complete the thigh finish the shin foam is pre-shaped to various stock sizes and will be similarly covered the completed leg is checked on the patient a range of knee mechanisms are available as with traditional legs but the advantage here is that components can be changed without constructional alterations to the leg so that once amputees have gained confidence with a simpler unit they can progress to 1 which can give them improved function and mobility one of the alternatives that could be prescribed is an automatic knee stabilizing device this enables weight to be applied to the leg even when the knee is bent once the weight is taken off the knee can move freely this versatility helps to meet the widely differing needs of amputees development of modular legs has been over seven years and during this time testing and assessment has been undertaken by the biomechanical research and development unit and scientific and technical branch at rel Hampton a special rig allows walking stress to be monitored and recorded the data collected is later analyzed by a computer this modular leg is believed to be the first in the world to have undergone such rigorous testing during development and continuing research is going on to effect further weight reductions without sacrificing safety and to extend the range of amputees programa can be prescribed each test run with up to seven variables can be monitored these tests are monitoring six individual aspects of load within the legs each test run produces up to 50,000 numbers that are recorded for later analysis this elaborate equipment helps to cope with the data handling problem and the visual display unit allows test variations to be simulated and the results tabulated in a convenient form before printed the analyzed results are then used to set the standards of strength that will ensure the structural safety of the leg when worn by amputees in this static destruction test a foot socket shin tube and cradle are compressed until breakage occurs in this case by five times the load of normal use such testing not only ensures the safety of the completed limb but indicates where redesign can safely achieve weight reduction another title destruction test involves a cyclic bending action this will also continue until a fatigue fracture takes place apart from the buret reassessment clinical trials were carried out for over three years before the leg was finally approved the general supply to National Health Service patients but whatever the test results the final approvals come from those who wear the leg are they able to lead a normal life in work and Recreation this man has amputations of both legs one above and one below the knee apart from his moped which he can ride with agility he also drives a car he undertakes internal decorating including the hanging of wallpaper which involves the use of step ladders this girl had a below-the-knee amputation six years ago then aged seven she also enjoys cycling swimming hiking using a trampoline and cross-country running another below-knee amputee who undertakes an active job in a slaughterhouse he's also worked in a butcher shop is a keen gardener during his own digging and drives a car without modification above knee amputation with only a short stunt she has a full time job which he gets to by public transport she enjoys dancing and has started riding again after a gap of six years this man with the lonely amputation works on the fire crash tender and in his spare time is able to enjoy boating without difficulty he plays football with his children swims maintains his own house including ladder work and roof repairs his job involves him in walking up to five miles a day he says he's in no way restricted in the type of life he wants to lead the people we've just seen and thousands like them are leading a full and active life with the aid of these modular legs in the manufacture of these legs quality control is assured by inspection checks at all stages of manufacture and assembly National Health patients are supplied with artificial legs through the British Health Department's from developments now being undertaken the adaptability and flexibility of the modular lower limb system will bring increasing benefits to patients of all ages and all levels of amputation