a diagram of the ankle is provided as fig1 . generally , an ideal ankle is considered to be one whose “ t - point ,” “ s - point ” and “ c - point ” in fig1 are arranged in a straight line and α - talocalcaneal angle = 0 °. the t - point is the mid - point of a line connecting right and left convex ends of the upper edge of the talus trochanter . the s - point is the mid - point of a line connecting the distal end of the fibula and the distal end of the tibia . the c - point is the mid - point of a line parallel to the floor at a position 2 . 5 - cm below the distal end of the fibula . the direction of force in which the body weight acts is t - point -& gt ; s - point and the direction in which a force resisting the gravity ( gravity - resisting force ) is c - point -& gt ; s - point . as described above , the positioning of t - point , s - point and c - point in a straight line , α - talocalcaneal angle = 0 ° is ideal . the greater the value of α - talocalcaneal , the greater the body weight that the knee joint and ankle must bear , and the greater the burden imposed on the knee joint and ankle . according to the therapeutic device of the present invention , the positional relationship between the femur and the tibia can be restored to normal or substantially normal when the patient walks on a flexible and resilient body under the medial or lateral foot . this reduces local pressure on the cartilage between the femur and the tibia and alleviates symptoms , including pain , of arthritis of the knee . according to the present invention , the body under the foot is used in conjunction with a stretchable band . the ankle is fixed by wrapping it with the stretchable band , whereby the aforesaid talocalcaneal angle , α , can be forcefully retained at substantially 0 ( zero ) degrees to further alleviate the symptoms , including pain , of arthritis of the knee . clinical data is provided in the embodiments that follow . further , in the therapeutic device of the present invention , the stretchable band strip extends to the right and left of the flexible and resilient body , so that the therapeutic effect can be increased by wrapping either side more tightly than the other as symptoms warrant , so as to achieve maximal therapeutic effect . in another embodiment , the therapeutic device of the present invention can be worn over a sock . this makes it possible to wear the article not only with ordinary shoes but continuously even while wearing open - toed shoes , boots , slippers , high - heels and if shoes are removed such as at home . the device is comfortable and easy for a patient to use , increasing patient compliance . since the flexible and resilient body is firmly fixed to the sole by attaching it to a stretchable band and wrapping said stretchable band around the flexible and resilient body , foot , and ankle as described above , the elastic body is stabilized and unlikely to become displaced during use . the present invention offers a further advantage over other types of wedged insoles . said flexible and resilient body is removably attachable to the stretchable band and can be easily removed or exchanged , washed , or replaced , according to circumstances ; thus , it does not generally cause or aggravate foot odor . this also permits the replacement of a worn elastic body and the constant wear of the therapeutic device , which exhibits superior performance in correcting the displacement of the talocalcaneal joint . further , the height of the flexible and resilient body can be easily adjusted in response to the progress of alleviation of the symptoms ; thus , the article is very convenient and adjustable . the preferred embodiment of the present invention is described in reference to the drawings . it is understood that the present invention is not limited to the particular methodology , protocols , material , etc ., described herein , as these may vary . it is also to be understood that the terminology used herein is used for the purpose of describing particular embodiments only , and is not intended to limit the scope of the present invention . it must be noted that as used herein and in the appended claims , the singular forms “ a ,” “ and ,” and “ the ” include plural reference unless the context clearly dictates otherwise . in addition , in the following description , the term “ conventional sole plate ” refers to an “ insole with one of the right - hand and left - hand sides made in greater height than the other .” fig2 is a side view of the present inventive therapeutic device ( 10 ), and fig3 is a perspective view thereof . in the figures , the reference character ( 12 ) denotes a stretchable band which is , for example , 5 - 10 cm wide and 50 - 80 cm long ( before stretching the maximum stretched length being , for example , 70 - 100 cm ). the front surface of one end portion of the stretchable band ( 12 ) has the male part of a hook - and - loop fastener ( 12 a ) attached thereto , while the back surface of the other end portion has the female part of said hook - and - loop fastener ( 12 a ) attached thereto . in addition , substantially the lengthwise middle of the stretchable band ( 12 ) has a flexible and resilient body ( 14 ) of soft polyurethane foam removably attached thereto . among the method for such removable attachment are one for attaching two parts by using a hook - and - loop fastener , and one for temporally fixing by sewing . the flexible and resilient body ( 14 ), as illustrated , is substantially triangular in cross section , gradually increasing in thickness toward one end of the stretchable band ( 12 ) ( or gradually decreasing in thickness toward the other end ). in addition , the shape of the flexible and resilient body ( 14 ) is not limited to the shape shown in the above embodiment ( see fig2 ); for example , a flexible and resilient body ( 14 ) having a portion of uniform thickness ( see fig9 ( a )), a flexible and resilient body ( 14 ) having a right triangular cross section in which one end of the upper surface of the flexible and resilient body ( 14 ) extends down to the upper surface of the stretchable band ( 12 ) ( see fig9 ( b )), or a flexible and resilient body ( 14 ) having a footrest of arcuate cross section ( see fig9 ( c )) may be employed , or other shapes may be employed . the method of treatment arthritis by applying the therapeutic device ( 10 ) of said arrangement is now be described . first , as shown in fig4 the therapeutic device ( 10 ) is placed on a floor to lie transversely . in this state , the foot is placed on the flexible and resilient body ( 14 ) directly from above . the placement of the higher portion , under the medial or lateral sole , should be on the side opposite the side of the knee that is experiencing pain . this means that if the medial knee aches , the higher side of the flexible and resilient body ( 14 ) should be under the lateral sole . as shown in fig5 with the foot placed on the flexible and resilient body ( 14 ), the flexible and resilient band ( 12 ) is wrapped around the ankle , and on the back of the ankle ( just at the position of the achilles &# 39 ; tendon ), the right - hand and left - hand side strips of the stretchable band ( 12 ) are fastened together by the hook - and - loop fastener ( 12 a ). as shown in fig5 - 7 , one end strip of the stretchable band ( 12 ) is held by hand and is moved from the anterior to posterior ankle and the other end strip is likewise moved in an anterior to posterior direction . the end strips are fastened at their overlapping portions by the hook - and - loop fastener ( 12 a ) at the position of the achilles &# 39 ; tendon on the posterior ankle , as shown in fig8 . thus , the ankle wrapped with the stretchable band ( 12 ) can be fixed by said stretchable band ( 12 ) with the foot placed on the flexible and resilient body ( 14 ). patient 1 : a 58 - year old female patient suffering from osteoarthritis of long duration was asked to wear the present inventive therapeutic device , and the structural condition of her ankle was assessed by measuring the α - talocalcaneal angle by x - ray photography . see fig1 . the result is shown in table 1 , below . table 1 compares the condition of the disease in patient 1 prior to wearing the present inventive therapeutic device , the condition of disease while wearing the present inventive device , and the condition of the disease while wearing the conventional sole plate . as is clear from the table 1 , the present inventive therapeutic device brings the value of α - talocalcaneal angle is nearly 0 °, providing a nearly ideal condition of the ankle . thus , it can be fully expected that the burden of body weight on the knee is alleviated as compared with the conventional sole plate . in fact , this patient began to feel less pain in the knee about a week after wearing the present inventive therapeutic device , and the pain in the knee almost disappeared two weeks after . a certain amount of correction is achieved with the conventional sole plate . however , as described above , such a sole plate is produced only after a mold has been produced , so that it is expensive . the one used in this clinical trial cost 6 , 000 yen . for this reason , it is thought that many patients will continue to use the sole plate even if the higher portion wears a little . when this occurs a certain amount of the correcting power and therapeutic effect is lost as time progresses and gradually disappears . moreover , there is a danger of a reverse effect and worsening of the symptoms . in contrast , in the present inventive therapeutic device , the flexible and resilient body is constructed in such a way as to be replaceable with respect to the stretchable band . even if the flexible and resilient body becomes worn , it is only necessary to replace such flexible and resilient body . hence , a therapeutic device exhibiting a superior correcting power can be worn at all times . further , the height of the flexible and resilient body can be easily adjusted in response to the progress of alleviation of the symptoms . the device is convenient and pleasant to use . nine ( 9 ) patients with osteoarthritis of the knee using conventional sole plates ( insole type , both new and after one year of use ), and 24 patients with osteoarthritis of the knee wearing the present inventive therapeutic device were studied . the structural condition of the ankle was assessed by measuring the α - talocalcaneal angle by x - ray photography as in the clinical result ( 1 ) above . the differences in the talocalcaneal angle , α , between patients standing on one foot wearing nothing , and wearing the conventional sole plate or the present inventive therapeutic article , changes in the α - talocalcaneal angle . mean correction factors , showing that the greater the positive value , the greater the correction , were examined . the results are shown in fig1 . as can be seen from the graph in fig1 , the mean difference in talocalcaneal angles between the control and treated values was 3 . 7 ° with the present inventive therapeutic article and 1 . 2 ° with the conventional sole plate when new . thus , the present inventive therapeutic device can be expected to provide a greater therapeutic effect than the conventional sole plate even when the sole plate is new . the conventional sole plate is expensive and tends to be used for many years , as described above . however , when one is used for one year , the sole plate conforms to the original foot shape and gradually loses its correcting power , thus showing a negative value of means correction factor of − 1 . 9 °. nine ( 9 ) patients with osteoarthritis of the knee using conventional sole plates ( insole type , both new and after one year of use ), and 24 patients with osteoarthritis of the knee wearing the present inventive therapeutic device were studied . the change in the femorotibial angles was used to determine the knee correction angle . fig1 depicts the differences in the knee correction angle , between patients standing on one foot wearing nothing , and wearing the conventional sole plate or the present inventive therapeutic device in changes in the knee corrective angle . the greater the negative value of the mean corrective angles , the greater the correction . the results are shown in fig1 . as can be seen from the graph in fig1 , the mean corrective value for the angle of the knee , the difference between the control and treated values , was − 3 . 1 ° with the present inventive therapeutic article and − 1 . 2 ° with the conventional sole plate . thus , the present inventive therapeutic device can be expected to provide a greater therapeutic effect than the conventional sole plate . twelve ( 12 ) patients with osteoarthritis of the knee complaining of pains with activities of daily living were asked to wear the present inventive therapeutic device every day , and changes in the severity of pain were examined before and after wearing . the results are shown in fig1 . as can be seen from fig1 , in each pain - inducing motion , the proportion of patients complaining of pains after wearing was reduced compared with that before wearing . particularly , the number of patients complaining of pains in the knees when getting up , both when getting out of bed in the morning and when starting to move , was 8 ( 67 %) before wearing , whereas after wearing , it was reduced by half to 4 ( 34 %), which is a remarkable effect .
the present invention relates generally to a therapeutic device and related methods for treating arthritis of the knee . the therapeutic device includes a stretchable band having a predetermined length , a flexible and resilient body installed in the longitudinal middle of the stretchable band with a substantially triangular cross - section whose height is greater at one side of the stretchable band than at the other , such that the higher portion of the flexible and resilient body is applied to the sole at a position nearer to the inner or outer side thereof , and the stretchable band may be used to wrap and fix the ankle .