Abstract:
Machines for treating or preventing neuromuscular pain conditions and injuries by slow patientcontrolled stretching of a muscle or group of muscles when they and surrounding muscles are in a relaxed state (i.e., with little or no extrafusal muscle fiber contractions). The machines include a fixed support such as seat. An adjustable support, such as a back or side rest is adjusted for the particular patient. A controllable support moved in an alternating motion, under the patient&#39;s control, allows the injured or painful muscle to be slowly stretched by gravity, while the muscles are relaxed. The controllable support is preferably moved by a hydraulic cylinder.

Description:
BACKGROUND OF THE INVENTION 
     The field of the invention is apparatus and methods for treating muscles and neuromuscular pain conditions. 
     Muscle injuries and pain, common among athletes and manual laborers, occur in the general population, due to accidents, over-exertion, and/or poor ergodynamic and working conditions. These types of injuries occur often in the neck, arms, hip, back, and shoulders. 
     Traditional therapies, such as in muscle strengthening, the most common approach to physical therapy, have no proven effect and often aggravate the pain. Other techniques such as heat or ultrasound are passive and also unproven. Active stretching of the muscle is more effective but has been traditionally performed by physical manipulation of the patient by the therapist, often resulting in over-stretch and a reaction of muscle tightening. 
     When a muscle is acutely strained, as in a lifting injury, there is pain in the injured muscle until tightness, swelling, bleeding and inflammation subside. Muscles surrounding the injured area tighten up in order to splint the site and prevent further damage, and these surrounding muscles also become painful. In addition, the muscle stretch receptors, called muscle spindles, become contracted. This spindle spasm can become chronic if tension coexists causing a sympathetically-mediated activation of the spindle. 
     SUMMARY OF THE INVENTION 
     It has now been discovered that, in contrast to prior physical therapy practices which emphasize muscle strengthening and/or active stretching, muscle injury and pain conditions are more effectively prevented or treated by using body weight and gravity to stretch, preferably slowly stretch, the injured or painful muscle while surrounding muscles are maintained in a generally relaxed state. This is accomplished by placing the body in such a position that muscles other than the muscle to be treated are relaxed while the injured or painful muscle, for example, is placed in such a position that body weight, optionally assisted by the addition of further weight, can be used to accomplish the treatment stretch. This is preferably accomplished with novel equipment designed to promote this gravity or relaxed stretching. Examples of such equipment are described and claimed herein. This equipment also preferably includes a means for allowing the stretch to be accomplished slowly and for returning the stretched muscle to the starting position without voluntarily contracting said muscle. The muscle injury prevention and therapy machines described herein offer an appropriate amount of muscle stretch, to reduce the risk of injury or reinjury and provide longer lasting relief, and accelerated patient improvement. The patient, via actuators on the machines, can control the degree of stretch on the affected muscle and then return to a neutral position, while maintaining a relaxed state in a gravity-dependent position. By providing for the addition of further weight, in the form of independent weight devices (such as weighted pads), or a means for adding a weight or weights to the equipment itself (such as by a tubular bar for holding barbell-type weights, secured to that portion of the equipment which moves to permit the stretch) and a means for securing the muscle to be treated to the equipment (such as by a strap), the gravity stretch may be enhanced. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings, wherein similar reference denote similar elements throughout the several views; 
     FIG. 1 is a perspective view of a first embodiment of the present invention useful, for example, for neck flexion treatment; 
     FIG. 2 is a side elevation view thereof illustrating the machine of FIG. 1 in use; 
     FIG. 3 is a partial section view taken along line  3 — 3  of FIG. 2; 
     FIG. 4 is a perspective view of a second embodiment of the invention, useful, for example, for treatment of the quadratus lumborum; 
     FIG. 5 is a front elevation view thereof; 
     FIG. 6 is an enlarged front elevation view showing of the machine of FIGS. 4 and 5 in use; 
     FIG. 7 is a perspective view of a third embodiment of the invention, useful, for example, for treating back extensor muscles; 
     FIG. 8 is a side elevation view of the machine of FIG. 7 in use; 
     FIG. 9 is a partial top view taken along line  9 — 9  of FIG. 8; 
     FIG. 10 is a perspective view of a fourth embodiment of the invention, useful, for example, for treating hip muscles; 
     FIG. 11 is a front elevation of the machine of FIG. 10 in use; and 
     FIG. 12 is a partial plan view of the adjustable leg support taken along line  12 — 12  of FIG.  11 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The most effective therapy for muscle injury and pain involves the slow gentle stretching of the involved muscle or group of muscles while they and surrounding muscles are in a state of muscle relaxation, such that there are little or no extrafusal muscle fiber contractions. While traditional methods of therapy have sometimes included stretching, the stretching has typically been 1) controlled by the therapist, not the patient; or 2) has involved contraction of the surrounding muscles, especially the antagonist muscles, e.g., stretching the back extensors by actively (voluntarily) contracting the back flexors (abdominal muscles); or 3) has used too rapid a stretch; or 4) has required active contraction to restore the patient to the original non-stretched position; or 5) was directed to achieving excessive stretch rather than conscious patient perception of changes in degree of muscle stretch. The following machines and methods achieve slow gentle stretching of specific muscles or groups of muscles, with the muscles in a relaxed condition while in a gravity-dependent position, thereby achieving highly effective therapy. The following machines and methods can also be used for warm-up stretching before exercising, to reduce the risk of muscle injury during exercise. 
     Turning now in detail to the drawings, as shown in FIGS. 1 and 2, the first embodiment  30  includes a T-shaped base  32  having a cross beam  34  attached perpendicularly to a main beam  36 . Mounting holes or brackets  38  are provided on the base  32 . A hollow seat pipe  40  extends vertically upwardly from the main beam  36 . A seat  44  having a seat post  42  with through holes is placed in the seat pipe  40  and secured in position via a lock pin  46 . 
     Similarly, a support riser  54  with through-holes can be vertically raised or lowered in a riser pipe  50  via a riser pin  56  extending through the riser pipe  50  and a riser section  54 . A torso bar  58  is similarly vertically adjustable on the riser  54  via torso bar pin  60  extending through holes in the torso bar  58 . Torso pads  62  are attached at the upper end of the torso bar  58 . Foot pads  64  are attached to the main beam, just froward of the seat pipe  40 . Referring now to FIGS. 1 and 3, the arm  78  is pivotally attached the riser  54  through a hinge joint  76 . An (azimuth) angle plate  72  is joined to the riser  54 . As shown in FIG. 3, the angle plate  72  has a plurality of spaced apart holes  74 , allowing the arm  78  to swing arc-like in either direction, and be locked at any particular angle by an arm pin  80  extending through a hole  74  in the angle plate  72  and into the arm  78 . Referring to FIG. 2, the seat pipe  40  and riser pipe  50  are inclined at angle θ, preferably ranging from about 70° to 88°, and more preferably about 82°, forwardly, (towards the end of the machine at the cross beams  34 ). 
     As best shown in FIG. 2, the lower end of an actuator, such as hydraulic cylinder  90 , is pivotally attached to a collet  84  slidably positioned over the arm  78 . Other actuators including electric, pneumatic, mechanical, etc. may also be used. The collet can slide in and out on the arm  78 , to shift the position of the lower end of the hydraulic cylinder  90  towards and away from the patient. A collet pin  86  extending through the collet  84  and arm  78  locks the lower end of the hydraulic cylinder into a desired position on the arm  78 . An angle linkage  94  and a clamp ring  96  are used to adjust and hold the inclination angle of the hydraulic cylinder toward the patient. 
     Hydraulic supply and return lines  114  and  116  extend from a hydraulic system (not shown) to a counter-balance valve  112  connecting to the hydraulic cylinder  90 . The counterbalance valve  112  is controlled by hand control  110 . A headpiece  98  is attached to the upper end of the hydraulic cylinder  90  via a swivel joint  118 . The swivel point allows the headpiece  98  to be moved into a desired position. 
     The embodiment shown in FIGS. 1-3 is intended for treatment of neck pain, cervical strain, and whiplash. It is also be useful for treating tension headache and myofascial pain syndrome. It can work on the sternocleidomastoids, splenius, levator scapulae and trapezium muscles. It can also be modified for treatment of other muscles. In use the patient adjusts the seat height, angle (if any) of the arm  78 , height of the torso pads  62 , and position of the base of the hydraulic cylinder  90  attached to collet  84 , by using the lock pins provided for each of those functions. The patient may also slide close to or away from the torso bar  58 , because of the extended seat length. The vertical position of the arm  78  is preferably adjusted by a technician. 
     The patient rests the forehead on the headpiece  98  and places the hands on the hand controls  110 . A variety of headpieces  98  are preferably provided, to match the patient and application. The headpieces  98  may be, for example, pillow, keyhole, or banana-shaped. The patient adjusts the position of the headpiece  98  and then locks it in position by placing weight of the head on headpiece  98 . With the patient in the starting position, as shown in phantom in FIG. 2, and with the machine  30  appropriately set, the patient actuates the hand control  110  to retract and lower the piston  92  into the hydraulic cylinder  90 , to a neutral position, between the anticipated full extension and full retraction positions for desired stretch. One technique is for the patient to stay in the stretch position for one slow inhale and exhale. This technique promotes awareness of the state of muscle stretch. After achieving a relaxed stretch, the patient reverses direction and, using the hand control  110 , causes the piston  92  to extend back to its original position. The patient may perform these steps as often as desired. The movement of the patient&#39;head and neck are shown in FIG.  2 . The patient remains seated at all times. 
     With the arm  78  straight ahead (at 12 o&#39;clock) the motion is pure forward flexion (the C-4 to C-7 vertebrae). If the base of the piston is changed to about 70 degrees and extended away from the patient by approximately 3-6 inches, the forward flexion will be from the T-4 to C-4 vertebrae. If the arm  78  is swung out to one side by about 20 degrees, as shown in phantom in FIG. 3, then the rotational and extensor muscles of the neck are also stretched. 
     The degree and speed of lowering and raising is under patient control. The stretch protocol can be progressed incrementally over time, with the patient advantageously working from a guideline for each week, based on past progress. The speed of actuator movement (in all embodiments) is preferably from about 0.1-2.0 about inches/second and more preferably about 0.5 inches/second. 
     As shown in FIGS. 4 and 5, a machine  130  useful for quadratus lumborum treatment includes a base  132 , a seat tube  134  attached to the base  132 , and a seat  136  pivotally attached on top of the seat tube  134  via a pivot joint  138 . The seat has an inner section  135  set as an angle to an outer section  137 . A seat end  140  is attached to the outer seat section  137 . A hydraulic cylinder has a lower end pivotally attached to a mount on the base  132 , and an upper end pivotally attached to an extension mount on the seat end  140  with an eyelet and clevis pivot  141  (FIG.  6 ). Hydraulic lines  168  and  170  connect the hydraulic cylinder to a control unit  172 . A hand controller  174  on a platform  178  is connected to the control unit  172  via control line  176 . The controller  174  preferably is provided in the form of a joystick moveable between up and down positions, through a center neutral or stop position. The platform  178  may be attached to the handle tube  152 . 
     A handle riser  154  with through-holes is vertically adjustable via a pin  162  within a riser tube  152  attached to the base  132 . A side support pad  142  is pivotally attached to a riser pad mounting bar  146  with through-holes vertically positionable within a side pad tube  149 . An angle plate  147  and pin  148  (FIG. 6) allows the side support pad  142  to pivot to various angles. A semi-circular handle bar  150  extends around either side of the seat  136 . The handle pivots up on a handle pivot joint  151 , and is attached to riser support bar  154 . 
     The embodiment shown in FIGS. 4-6 is primarily intended for treatment of lower back including the quadratus lumborum muscle. In use, the side pad  142  height and angle is adjusted for the patient. The seat  136  is initially level. The patient approaches the seat so that the affected side will be on the outside of the machine away from pad  142 . The patient sits on the seat and allows his legs to dangle down freely. The patient then slides to the far inside of the seat until the side pad  142  is against his side and the top of the pad is several inches under the axillary region. The torso is therefore supported on the side opposite to the side being stretched. The patient may increase the stretch by holding onto the curved handle  150  in front of him. The patient is also able to lean forward or twist away from the side being stretched, to enhance the effects of the stretch. The patient may also lean over the side torso pad (lateral flexion away from the stretch) which puts the portion of the quadratus opposite this, on greater stretch. 
     The patient then grasps the handle of the controller  174  with his free hand. By advancing the controller or joystick forward, the seat begins to lower the affected side. Specifically, the controller  174  causes the hydraulic cylinder  90  to retract, moving the seat  136  smoothly about the pivot joint  138 . Since the inner seat  135  is angled downwards relative to the outer seat  137 , it elevates less as the outer seat  137  lowers. As this occurs, the patient&#39;s back sequentially extends laterally and interiorly stretching the quadratus lumborum muscle in a controlled and relaxed manner. “Relaxed” means with little or no required extrafusal muscle contraction. As the side being stretched slowly lowers, the patient determines the amount of stretch by joystick control. 
     When the desired range of movement is reached, the patient moves the handle control  174  the other direction, causing the hydraulic cylinder  90  to extend, pushing the seat  136  back to the horizontal position. It is preferable to pause briefly at each increase of stretch. After sufficient repetitions, the patient switches sides and repeats the process, to stretch the opposite quadratus lumborum in the other direction. FIG. 5 shows the seat in the down (stretched) position while FIG. 6 shows it in the up (start) position. 
     Turning to FIG. 7, an embodiment  200  useful for treating back extensor muscles, has a base  202  and floor mounting plates  204 . A back support post  206  attached to the base  204  telescopically supports a back pad riser  208 . The riser  208  has a plurality of vertically spaced apart holes, so that the vertical position of the back support riser  208  may be adjusted in the back support post  206  using a riser pin  210 . A back pad arm  212  with through-holes extends forwardly from an arm bracket  214  attached to the back pad riser  208 . 
     Turning to FIGS. 7 and 9, a back pad assembly  216  is attached at the front end of the arm  212 . The back pad assembly  216  includes padded rollers  218  supported on roller supports  220 . The front to back position of the back pad assembly  216  may be adjusted by sliding the arm  212  front or back and locking the arm in position on the bracket  214  via an arm pin  222 , extending through a selected hole in the arm  212 . 
     Turning to FIG. 8, the embodiment  200  includes an actuator  230  pivotally attached to the base  202  via a pivot  236 . Hydraulic lines  240  and  242  connect to a center-balance valve in a patient hand controller (not shown) as described above with reference to FIG. 4. A seat support  244  is pivotally attached a seat post  250  extending up from the base  202  via a seat pivot  252 . A seat pad  246  is attached to the seat support  244 , forming a seating surface having a straight or flat inner end  245 , and an upwardly angled outer end  247 . The piston  234  is attached to the underside of the seat support  244  at a piston pivot  238 . 
     A leg pad  254  is supported on a leg pad arm  256  extending perpendicularly forward from the seat post  250 . The leg pad  254  preferably forms an acute angle with the seat post. 
     A handle bar post  260  extends upwardly from the base  202 , and telescopically supports a semi-circular handle bar riser with through-holes  262  in an adjustable vertical position via a pin  264  extending through the post  260  and a selected hole in the riser  262 . Referring momentarily to FIG. 7, a c-shaped handle bar  268  is attached to the handle bar riser  262  at a handle bar pivot  266 , so that the handle bar  268  can pivot upwardly (as shown in phantom in FIG.  7 ). 
     In use, the patient raises the handle bar  268 , sits on the seat pad  246  and then lowers the handle bar. The patient&#39;s legs rest on the leg pad  254 , and the patient&#39;s back is positioned against the back pad assembly  216 , with the seat in the upright and horizontal position, as shown in phantom in FIG.  8 . This is the start position. The patient holds the handle bar  268  with one hand, with the other hand on the controller  174 . By operating the controller, the patient causes the actuator  230  to slowly retract. As this occurs, the seat  246  slowly pivots downwardly about pivot  252 . Correspondingly, the patient&#39;torso flexes forwardly. The roller pads  218  roll upwardly on the patient&#39;s back. As shown in FIG. 9, the lower roller supports  220  are straight across, the middle set of rollers is inclined inwardly, and the top set of roller supports is inclined inwardly still farther. 
     After the patient has reached the maximum comfortable stretch position (which will vary from patient to patient, and will also vary for the same patient depending on various factors), using the controller  174 , the patient then reverses the procedure by causing the actuator  230  to extend, thereby pivoting the seat back to its horizontal starting position. 
     Turning to FIGS. 10-12, in an embodiment  300  useful, for example, for treating hip muscles, includes a frame  302  is supported on legs  304 . A frame extension  310  supports movable leg pads  318  on leg frame supports  319 . A frame pad  306  extends over the entire top of the frame  302 . A slide plate  314  is attached to each leg pad  318  and is vertically displaceable along guide bars  312 . An actuator  320  is attached to the lower end of the frame extension  310  at a lower pivot joint  322 . The upper end of the actuator  320  is attached to one of the slide plates  314  at a slide plate pivot joint  324  via an attachment pin  325 . The pin  325  can be quickly removed to switch the attachment of the actuator  320  from one slide plate to the other. An elevation plate  326  is attached to each slide plate  314  and extends under each leg support  319 . An elevation pin  328  allows the leg frame support  319  and pad  318  to be tilted up or down about an axis parallel to the pin  328 . 
     In use, as shown in FIG. 11, the patient lies on the frame pad  306  on his side. The patient&#39;s top leg (the right leg in FIG. 11) rests on the leg pad  318  in the elevated position, as shown in phantom in FIG. 11, with the patient&#39;lower leg on the frame pad  306 . Leg position may be improved by pivoting the frame  319  and the pad  318  with slide adjustment mount  326  down from level, and securing them in place via the locking pin  328 . Using a hand controller  174 , as shown and described above with reference to FIG. 6, the patient controls the actuator  320  which slowly drops the leg pad  318 , e.g., to the position shown in solid lines in FIG.  11 . The patient&#39;s hip and leg muscles are preferably relaxed, with all lifting performed entirely by the actuator  320 . After the leg pad  318  has reached the patient&#39;s desired degree of hip stretch, the patient reverses the hand controller  174  to cause the leg pad  318  to move back up to its original position above the level of the frame pad  306 . To treat hip muscles on the other side, the patient reverses position on the frame pad  306 , so that the upper leg becomes the lower leg on the opposite leg pad, and the stretching procedure repeated. 
     The embodiment  300  can also be used for treating shoulder muscles, i.e., the infraspinatus, teres major and rhomboid. In this application, the patient lays on the frame pad  306  face up, with patient&#39;forearm on the leg pad  318 . The movement of the leg pad, as described above, then stretches the shoulder muscles. 
     A computer or microprocessor controller  350 , as shown in FIG. 7, may also be used to control the machines described above. The computer can be programmed to provide specific speeds and durations of stretch, thereby simplifying use of the machines by patients. 
     Under certain conditions, it may be preferable for the body part being treated to be weighted down. Straps  352  with weights  354  can be placed over the body part for this purpose, for example as the body part is stretched on a machine. 
     Various other muscles, such as the latissimus dorsi and the brachioradialis can also be stretched using the machines described herein, or with modifications that would be apparent to those skilled in the art. 
     Thus, while several embodiments and applications of the methods and apparatus of the invention have been shown and described, it will be apparent to those skilled in the art that many more modifications, substitutions, and equivalents are possible without departing from the inventive concepts herein and to treat additional muscle groups. The invention, therefore, should not be restricted, except in the spirit of the following claims.