Patent Application
20060247097
The present invention relates to a method and apparatus for the standardized evaluation of body kinematics. More specifically, the present invention is concerned with a method and apparatus for the standardized evaluation of the three-dimensional kinematics of the knee.
Knee pain and injuries are quite common in athletes and sports enthusiasts of all types. In particular, knee ligament strains and tears can often result from strenuous activity, vigorous sports, and other such physical situations wherein the knee, whether healthy or generally prone to injury, is required to move against a restrictive force or weight. As a result, evaluation practices and methods have been developed to study and monitor the movement of the knee to evaluate the dynamics and kinematics thereof.
For instance, U.S. Patent Publication No. 2003/0018283 for a “Feedback Estimation of Joint Forces and Joint Moments” by Dariush and published on Jan. 23, 2003, teaches a 2 D simulation system and algorithm for studying the dynamics of the body during a squatting motion. Using recursive calculation of the moments and forces in the various joints, starting from measurements of ground reaction forces and combining them with measured or desired body kinematics, the simulation works its way up through the body to evaluate torque and reaction forces in successive joints of the body.
U.S. Patent Publication No. 2003/0115031 for a “Simulation System, Method and Computer-Readable Medium for Human Augmentation Devices” by Dariush et al. and published on Jun. 19, 2003, teaches a 2D simulation system and algorithm that estimates joint angles in the body, namely during a squat motion, based on measured torque values at these joints.
U.S. Patent Publication No. 2002/0139185 for a “Power Tester” by MacFarlane et al. and published on Oct. 3, 2002, teaches a device that estimates the power applied by a body member to displace an object using time measurements of the body member's motion against a restricting force applied by the object. Such estimates can be used to evaluate the strength of a patient, for example in various joints such as the knee, to assess the health of the patient's joints or again to monitor the recovery thereof after an injury.
Yet, though various monitoring and simulation systems exist to evaluate the condition of a patient's knee, there is a need for a system and apparatus optimizing the repeatability of measurements and analyses, namely in scenarios reflecting the natural movement of the knee in day-to-day and athletic activities. For instance, a system and apparatus that can isolate a standardized natural motion of the knee, that is a motion that is commonly repeated and executed throughout various daily and athletic activities and provide means for ensuring repeatability of such a motion to provide consistent and reproducible results, could increase diagnostic reliability through standardized measurement comparisons. The present invention, as described herein, seeks to meet these needs and other needs.
It is therefore an aim of the present invention to provide a method for monitoring a knee of a patient executing a controlled leg pushing motion in view of monitoring a condition of the knee.
It is also an aim of the present invention to provide a gesture-guiding apparatus for controlling a leg pushing motion of a patient in view of monitoring a condition of at least one of the patient's knees.
It is a further aim of the present invention to provide a system for monitoring at least one knee of a patient executing a controlled leg pushing motion in view of monitoring a condition of the knee.
More specifically, in accordance with the present invention, there is provided a method for monitoring at least one knee of a patient executing a controlled leg pushing motion applied through his feet in view of monitoring a condition of the knee, the method comprising the steps of:
a) providing a gesture-guiding apparatus and a monitoring device configured to monitor the at least one knee while the patient executes the controlled pushing motion using the gesture-guiding apparatus, the apparatus comprising a foot-bearing surface for positioning the feet of the patient thereon, a body alignment structure for providing an upper-body alignment of the patient thereon and a guiding mechanism for guiding a substantially linear displacement of the alignment structure relative to the surface through the pushing motion;
b) positioning the patient in the gesture-guiding apparatus according to a pre-selected position;
c) having the patient execute the motion; and
d) monitoring the at least one knee using the monitoring device as the patient executes the motion.
Also in accordance with the present invention, there is provided a gesture-guiding apparatus for controlling a leg pushing motion of a patient in view of monitoring a condition of at least one knee of the patient, the apparatus comprising a foot-bearing surface, an upper-body support structure comprising at least one body alignment mechanism for providing an upper-body alignment of the patient thereon, a guiding mechanism for guiding a substantially linear displacement of the support relative to the surface through the leg pushing motion and a resistance mechanism -for adjusting a resistance to the motion, the resistance comprising a weight resistance and the resistance mechanism comprising at least one counterweight to reduce the weight resistance.
Still in accordance with the present invention, there is provided a system for monitoring at least one knee of a patient executing a controlled leg pushing motion applied through his feet in view of monitoring a condition of the knee, the system comprising a gesture-guiding apparatus and a monitoring device configured to monitor the at least one knee while the patient executes the controlled leg pushing motion using the gesture-guiding apparatus, the gesture-guiding apparatus comprising a foot-bearing surface for positioning the feet of the patient thereon, a body alignment structure for providing an upper-body alignment of the patient thereon and a guiding mechanism for guiding a substantially linear displacement of the alignment structure relative to the surface through the pushing motion.
Still further in accordance with the present invention, there is provided a method for monitoring at least one knee of a patient executing a controlled leg pushing motion applied through his feet in view of monitoring a condition of the knee, the method comprising the steps of:
a) positioning the patient in a gesture-guiding apparatus and with a selected position for an upper body of the patient;
b) having the patient execute the motion, wherein the upper body displaces substantially linearly; and
c) monitoring the at least one knee as the patient executes the motion.
Other aims, objects, advantages and features of the present invention will become more apparent upon reading of the following non-restrictive description of specific embodiments thereof, given by way of example only with reference to the accompanying drawings.
In the appended drawings:
When it is desired to evaluate the 3D kinematics of the human knee, there are difficulties in that the 3D movements of the knee are affected by the movement of the leg during squatting. A ruptured ligament will also affect this kinematics. With a view to evaluate the impacts of various pathologies and of various treatments therefor on the kinematics of the knee, this kinematics must be evaluated during a reproducible movement of the knee and with a load being applied on the knee.
A gesture-guiding apparatus has thus been developed, wherein the trunk (torso) and feet of the patient are adequately stabilized thereby, to allow a patient to exert a reproducible movement, optionally against an adjustable resistance, in view of establishing a standardized evaluation of the 3D kinematics of the knee. The present guiding apparatus, used in combination with an appropriate kinematics sensing and monitoring device and system, could be for instance used to evaluate the kinematical repercussions on the knee of a ruptured anterior cruciate ligament and of its surgical repair, or of other such knee injuries, conditions and treatments.
Referring to
With particular reference to
Accordingly, the apparatus D is comprised of a foot-bearing surface 14, an upper body alignment and support structure 16 and a guiding mechanism 18 designed to guide a controlled substantially linear displacement of the alignment structure 16 relative to the foot-bearing surface 14.
In this illustrative embodiment, the foot-bearing surface 14 is comprised of a flat surface 20 and a set of foot-retaining structures 22 mounted thereon for fixedly positioning the feet of a patient therein. For instance, the foot-retaining structures 22 could include a set of straps, bindings or the like providing repeatable positioning of the patient's feet and stabilizing the position thereof during the pushing motion. These foot-retaining structures 22 may also be adjustably mounted to the foot-bearing surface 14 to allow initial (i.e. before undertaking the squatting motions) adjustments to the patient's foot positions. Such adjustments may include lateral, forward, backward and torsional rotations of the feet, various foot alignments, distancing and the like. Ultimately the position and orientation of the patient's feet should be selected to provide for an adequate monitoring and interpretation of the patient's knee's dynamics and kinematics during a given motion.
Still referring to
Again still referring to
Referring to
Referring now to
In addition to the sensor bands 44, the monitoring system M may also comprise one or more load-measuring platforms 52, optionally integrated within the foot-bearing surface 14, to monitor the actual load supported by each foot during the guided motion of the patient. By combining load data acquired by the platform 52 with kinematics data acquired by the sensor bands 44, a better analysis and evaluation of the patient's condition and health may be attained through combined kinematics and dynamics studies. Namely, standard variations of the 3D kinematics and dynamics of the knee could be established for a series of known knee conditions, ranging from the kinematics and dynamics of a healthy knee, a knee supporting and recuperating from various injuries, a knee recuperating after various surgical and/or therapeutic interventions, and the like.
In
Once the patient is securely aligned on the apparatus 12, he/she may proceed in executing a set of controlled motions, illustrated here as a vertical motion along arrow A between the standing position (
Optionally, a resistance to the patient's motion using the apparatus D may be adjusted. In a first exemplary situation, the resistance is increased by adding weights 54 to the bars 42 such that the patient must push against a resistance combining his/her own weight and the added weights 54 to complete the guided motion. In a second exemplary situation, the counterweight may be adjusted to substantially exactly counter the weight of the alignment structure 16 such that the patient must only push against his/her own weight to complete the guided motion. In a third exemplary situation, the counterweight may be adjusted to counter a significant fraction of the patient's weight such that the patient only pushes against a reduced weight. This third situation may be quite useful when evaluating and treating patients having injured knees or insufficient leg strength to overcome their own weight in a squatting motion. This situation may also help an injured patient progress to an increased range of motion while building strength in his/her knees and legs as part of a therapeutic and evaluation practice.
As described hereinabove, the motion of the patient is also monitored through the monitoring system M in view of evaluating, for example, the 3D kinematics of the patient's knees under various load resistances.
Referring now to
The alternative gesture-guiding apparatus D′ is again designed to guide a patient using the apparatus D′ through a controlled leg pushing motion, as illustrated by the vertical arrow A′ in
In this second illustrative embodiment, the foot-bearing surface 114 is again comprised of a flat surface 120 and a set of foot-retaining structures 122, here comprising a set of straps mounted to the surface 120 for fixedly positioning the feet of the patient therein. The foot-bearing surface 114 is generally mounted parallel to the ground and can optionally be horizontally displaced along arrow B to provide various patient positioning options. As described hereinabove with reference to apparatus D, a weight measuring platform 124 or apparatus may also be incorporated in the foot-bearing surface 114 to provide patient loading data to enhance knee monitoring and evaluation procedures.
Referring now to
The guiding mechanism 118 is comprised of a set of guide rails 134 extending substantially vertically from a base 136 of the apparatus D′ and adapted to accept the gliding movement of the guide couplers 133 of the body rack 126 thereon. An adjacent set of weight guides 138, holding a selectable weight stack 140 thereon, also extends substantially vertically from the base 136 and connects to the guide rails 134 through a structural coupler 142 mounted at the top ends thereof, thereby solidifying the combined structure. A pulley system (not shown) mounted within the structural coupler 142, provides a chain or cable 144 that couples the selectable weight stack 140 to the body rack 126 such that a downward motion of the rack 126 along the guide rails 134 induces an upward motion of selected weights 145 in the weight stack 140 along the weight guides 138. (Methods for selecting weights in the weight stack using weight bearing pins, selectors and the like should be apparent to a person of skill in the art and will thus not be described in detail herein).
Referring now to
An appropriate counterweight may then be selected. In general, an appropriate counterweight will be defined by the physical condition and strength of the patient's knees and legs. For instance, if a patient is recovering from a serious injury or surgery, a larger counterweight may be selected to provide very little resistance to the patient's pushing motion. Alternatively, as a patient's knees become stronger, greater resistance may be applied. Also, resistance settings will likely vary from one patient to another depending on muscle strength and conditioning. Furthermore, additional weight settings may also be incorporated in the design of apparatus D′. For instance, to increase a resistance to the patient's motion beyond the patient's own weight, additional weights may be mounted to the body support rack 116 using weight bearing bars and the like, as described hereinabove with reference to the first embodiment.
Once an appropriate resistance has been selected, the patient is guided by the apparatus D′ to execute repeatable leg pushing motions, as indicated by arrow A′. As described hereinabove with reference to the first illustrative embodiment, a monitoring system as in M, again possibly comprising a set of sensing straps and the like, will monitor the kinematics of the patient's knees during the controlled motion in view of evaluating the patient's condition. Combining kinematics data with load data extracted from the load-measuring platform 124 may also be used to extrapolate patient knee dynamics. Again, since the patient's upper body is securely aligned with the support structure 116, consistent and repeatable data may be obtained and evaluated against comparable standardized kinematics data.
Referring now to
The gesture-guiding apparatus D″ is again designed to guide a patient using the apparatus D″ through a controlled leg pushing motion. Accordingly, the apparatus D″ is comprised of two foot-retaining structures 214, an upper body alignment and support structure 216 and a guiding mechanism 218 designed to guide a controlled substantially linear displacement of the alignment structure 216 relative to the foot-retaining structures 214.
In this third illustrative embodiment, the foot-retaining structures 214 are pivotally mounted on a base portion 220 of the apparatus D″ such that a forward/backward rotation of the patient's feet may be adjusted. A forward/backward position of the patient's feet may also be adjusted by adjusting a position of the foot-retaining structures relative to the base portion 220. As described hereinabove with reference to apparatuses D and D′, a weight measuring platform 222 or device may also be incorporated in the foot-retaining structures 214 to provide patient loading data to enhance knee monitoring and evaluation procedures.
The upper body alignment and support structure 216 is illustratively comprised of a pelvic support 224, a backrest 226, a shoulder rest 228, a headrest 230 and two shoulder pads 232, all optionally adjustable to accommodate various users and user sizes. A set of optional straps and belts may again be provided to secure the patient's position on the support structure 216. The support structure 216 also further comprises a series of guide couplers 234 allowing the structure 216 to glide up and down the guiding mechanism 218.
The guiding mechanism 218 comprises of a set of guide rails 236, solidly mounted to a framing structure 238 and extending substantially vertically from the base 220 of the apparatus D″, adapted to accept the gliding movement of the guide couplers 234 of the body support 216 thereon. A pulley system 240, comprising a set of pulleys 241 collinearly mounted atop the framing structure 238, provides a chain or cable 242 that couples the body support structure 216 to a counterweight 244 such that a downward motion of the structure 216 along the guide rails 236 induces an upward motion of the counterweight 244.
To use the apparatus D″, a patient's feet are carefully positioned on the foot-retaining structures 214, which are themselves properly aligned and positioned, and the patient's upper body is carefully aligned with the body alignment and support structure 216. For instance, the patient should rest his/her pelvis, back, shoulder and head on the pelvic support 224, the backrest 226, the shoulder rest 228 and headrest 230 respectively and position his/her shoulders below the shoulder pads 232. Optional waist, chest, shoulder and head straps and belts (not shown) may also be used to fasten the patient to the support structure 216 to secure the patient's upper body alignment thereon.
Again, an appropriate counterweight 224, defined by the physical condition and strength of the patient's knees and legs, may be selected. Also, additional weight settings may also be incorporated in the design of apparatus D″, for instance to increase a resistance to the patient's motion beyond the patient's own weight, by mounting weights to the body support structure 216 using weight bearing bars and the like, as described hereinabove with reference to the first embodiment.
Once an appropriate resistance has been selected, the patient may be guided by the apparatus D″ to execute repeatable leg pushing motions. As described hereinabove with reference to the first illustrative embodiment, a monitoring system as in M, again possibly comprising a set of sensing straps and the like, will monitor the kinematics of the patient's knees during the controlled motion in view of evaluating the patient's condition. Combining kinematics data with load data extracted from the load-measuring platform 222 may also be used to extrapolate patient knee dynamics. Again, since the patient's upper body is securely aligned with the support structure 216, consistent and repeatable data may be obtained and evaluated against comparable standardized kinematics data.
From the above description, it should now be apparent to a person of skill in the art that other gesture-guiding apparatuses could be constructed to provide a similar result. For instance, though the above illustrative embodiments present a gesture-guiding apparatus oriented to provide a substantially vertical guided motion, other apparatus configurations and orientations may be considered without departing from the general scope and nature of the present disclosure.
For example, an apparatus providing an angled linear motion of an upper body support structure relative to a foot-bearing surface could be constructed to reduce gravitational load on the apparatus generated by the weight of the user. In this example, the patient's leg pushing motion could be guided on the angled apparatus and a resistance thereto could be adjusted using any of the above-described resistance mechanisms. Namely, weights could still be added to an angled upper body support structure to increase a resistance to the leg pushing motion and counterweights could still be coupled to the angled upper body support structure, possibly using a pulley system, to decrease the resistance.
Alternatively, an apparatus providing a substantially horizontal linear motion of an upper body support structure relative to a foot-bearing surface could also be constructed to provide a like effect. For instance, the upper body support structure could glide horizontally relative to the foot-bearing surface using a horizontal guiding mechanism. A resistance mechanism, such as a set of weights or a weight stack coupled to the body support structure through an appropriate pulley system could provide an adjustable resistance to the horizontal motion. For example, a selectable set of weights could be guided in a vertically upward movement as the upper body structure and the foot-bearing surface are relatively distanced in a horizontal motion. A patient using this type of apparatus would thus not work against his/her own weight but against a selectable weight resistance.
Also, though the above-illustrated apparatuses involve a static foot-bearing surface and a mobile body support structure, the reverse could also be implemented such that the patient's upper body remains immobile as the patient pushes on a guided footplate. Such an apparatus, potentially categorized as a leg-press apparatus or an inverted squatting apparatus, could provide a similar result, namely by securing an alignment and orientation of the patient's upper body during the leg-press motion.
Furthermore, though the above illustrative embodiments describe weight and counterweight implemented resistance settings, a person of ordinary skill in the art will understand that other resistance mechanisms and systems may be considered to provide a like effect. Namely, pneumatic and hydraulic systems common with conventional weight training apparatuses may be used in apparatuses D, D′, D″ and their above-described alternatives to adjust the resistance settings thereof without departing from the general scope and nature of the present disclosure.
It should now be apparent to a person of skill in the art that other such alternative apparatus constructions, configurations and orientations, as well as other types of resistance mechanisms therefor, can be considered herein without departing from the general scope and nature of the present disclosure.
Finally, although the present invention has been described hereinabove by way of specific embodiments thereof, it can be modified, without departing from the spirit and nature of the subject invention as defined in the appended claims.
