1. Field of the Invention
The invention relates generally to the field of physical therapy methods and apparatus to prepare an injured ankle joint for the strengthening process inherent in physical medicine and rehabilitation by reducing pain and stiffness, while increasing flexibility and range of motion.
2. Description of the Prior Art
U.S. Pat. No. 4,306,714 to Loomis, et al. filed Dec. 22, 1981 “Iso-energetic Ankle Exerciser” discloses an exercise device for the hands or feet in which the user supplies the force and motion by one hand or foot which will be countered by a resistance and similar motion of the other hand or foot.
This instrument rotates in three axes and is capable of being restrained from movement in each axis independently. The possible movement is therefore about any one of the three axes with the two other axes locked, any combination of two axes with the remaining axis locked, or rotation about all three axes with no rotational locks in place.
The rotational movement about any given axis of one foot is duplicated with an equal rotation about the same axis by the other foot. Rotation in three dimensions about either the X, Y or Z-axis or any combination thereof is possible.
Rotation about the Z-axis provides flexibility and strength training of the appropriate muscle group. Rotation about the X-axis provides flexibility and strength of the Dorsi-Flexor and extensor muscles of the foot and ankle. Rotation about the Y-axis provides flexibility and strength of the lateral (inversion and eversion) muscle groups. Each foot is secured to an individual platform, which assures that the desired foot movement and muscle involvement is obtained. The multiple axis unit is designed to exercise the lower leg, ankle and foot via reciprocal resistance, controlled by the individual using the unit The unit allows rotation of the foot about three axes to enhance both training and rehabilitation. This exercise unit will improve flexibility and range of motion in the lower leg, ankle and foot. In addition, the general strength of the muscles of the lower leg which support the ankle will be increased through isolated contralateral resistance movements.
U.S. Pat. No. 4,432,543 to Normandin, filed Feb. 21, 1984 “Physiotherapeutic Self-exerciser” discloses a physiotherapeutic self-exerciser which enables a patient to apply traction to the muscles or tendons of the feet whereby the patient may exert the necessary tension which is required to exercise a tendon or muscle to be treated. The exerciser includes a sabot (similar to a sandal or shoe having a band of leather or other material across the instep) to which the patient's foot is attached and a pair of levers which are manually engageable by the patient. The patient gradually applies weight to the levers connected to the sabot, thereby exerting an upward tension of the sabot, and the latter, combined with the flexing of the patient's knee, exerts a predetermined traction on the tendon or muscle to be treated.
The foot is solidly tied to the sabot, which pivots around an axis associated with a base. On an appropriate support affixed to this base, a system of levers is articulated and tied to a pre-determined point of the sabot structure. While flexing the knee, the patient gradually applies weight to the lever system, which exerts an important upward tension on the sabot. The tension, combined with the flexing of the knee, exerts the required traction on the affected tendon.
U.S. Pat. No. 5,879,272 to Mekjian, filed Mar. 9, 1999, “Adjustable Physical Therapy Apparatus” discloses an apparatus consisting of a support base on which is mounted a horizontally oriented bounding platform assembly support bar so as to be vertically adjustable with respect thereto. The bounding platform assembly consists of two pivotally connected bounding platforms, which are selectively draped over the support bar so that the free ends thereof rest upon the floor. The angle of inclination of the pivotally connected bounding platforms is selectively variable by vertically adjusting the support bar with respect to the support base so as to provide bounding surfaces for vigorous lateral rehabilitation exercises by the patient. The two adjustable physical therapy units are attached in an end-to-end relationship so as to provide adjacent bounding platforms with a reverse angle of inclination so as to provide bounding surfaces for vigorous medial rehabilitation exercises by the patient. The apparatus is specifically adaptable for selective rehabilitation exercises by a patient to improve the strength and stability of injured joints in the lower body extremities, i.e. the ankles, knees and hips. The opposed, inclined platforms enable the patient to perform selective bilateral bounding activity on the inclined platforms by pushing off with one leg from one inclined platform and landing with the other leg on the opposite inclined platform. This results in beneficial rehabilitating stress along the lateral aspects of the joints as the bounding activity is repeated with resultant increased strength in the injured joint.
The above and numerous other patented exercise devices, are intended for strengthening the lower leg muscles that control the ankle joint.
What is needed, and not provided by the prior art, is an apparatus and method of use that will prepare a previously injured ankle joint for the strengthening exercises inherent in the physical medicine/rehabilitation process by reducing pain and stiffness and increasing flexibility and range of motion.
Ankle sprains and fractures with soft-tissue and osseous, respectively, damage, are common injuries, especially among active individuals and athletes. The treatment of ankle soft tissue injury typically involves control of pain and swelling, and increasing range of motion in preparation for resistive, strengthening exercises. Routines that include early mobilization (passive oscillatory movement applied at a joint to increase accessory movement or to modulate pain.) and stretching of musculotendinous tissues have led to early return to activities.
Existing treatment involves manual mobilization techniques, which, although generally effective, lack replicability from one patient to the next and, from one physical therapy practitioner to the next The force of manual mobilization also is difficult to quantify. The stretching of musculotendinous ligamentous and joint capsular tissues is a basic need to enable users to duplicate mobilizations and quantify forces applied.
The talocrural (ankle) joint consists of the articulation between the trochlea of the talus and the mortise which includes the medial malleolus of the tibia, the lateral malleolus of the fibula and the distal articulating surface. The talocrural joint allows plantarflexion (downward pointing) and dorsiflexion (raising) of the foot. It is generally accepted that during ankle dorsiflexion, the talus rolls and glides posteriorly in relation to the mortise. These accessory motions of glide are frequently impaired as a result of an ankle injury resulting in dysfunction of movement.
This dysfunction can manifest itself in hypermobility, an increase in the range of movement of which a bodily part and especially a joint is capable or, hypomobility, the decrease in the normal range of joint movement, often characterized by the loss of accessory movements. Accessory movements are defined as joint movements that cannot be performed voluntarily or in isolation by the patient. Glide and roll of the talus in the mortise are considered accessory movements. Studies have shown significant improvements in dorsiflexion range of motion and restoration of normal gait patterns after anterior to posterior mobilizations of talocrural and proximal tibiofibular joints. See: Dananberg, H. J., Shearstone, J., & Guillano, M. (2000). Manipulation method for the treatment of ankle equinus J Am Podiatric Med Assoc 90, 385389 PubMed Full Text and Denegar, C. R., Hertel, J., & Fonseca, J. (2002). The effect of lateral ankle sprain on dorsiflexion range of motion, posterior talar glide, and joint laxity J Orthop Sports Phys Ther 32, 166173 PubMed.
The existing treatment method consists of passive manual mobilization of the ankle joint by the physical therapy practitioner. This practice, although generally effective, is subject to inconsistent results due to essential variables in its application. Differences in physical stature and strength from one physical therapy practitioner to the next greatly affect the efficacy of the procedure.
Differences in facilities such as table height and construction will also change the results of the mobilization procedure as the body position and, associated leverage, of physical therapy practitioner changes with the facilities.
Typically, passive manual mobilization techniques do not allow active movement of the joint, particularly dorsiflexion that is beneficial during mobilization.
Communication between the physical therapy practitioner and the patient regarding pain intensity is critical in the prior art method. Certain more aggressive mobilization techniques run the risk of shock loading the patient's ankle joint, i.e. applying the force too quickly and/or forcefully. The slightest delay in communicating pain can result in undesired results such as increased and prolonged pain and delayed recuperation.
During early stages of rehabilitation, patients can experience frequent intense pain. Physical therapy in general and, more specifically, mobilization reduces the intensity and frequency of the pain. Unfortunately physical therapy appointments are not daily events resulting in the patient having to endure pain on days without appointments. It is not possible to perform manual mobilization of the ankle joint on oneself.
It is therefore desirable to provide an apparatus that can be used in rehabilitation and physical therapy of the human ankle. The primary purpose is to increase the flexibility of the tendons, ligaments and joint capsule in the ankle through stretching and mobilization of the talocrural joint at the ankle mortise of the talus
It is desirable to provide a method and apparatus, which solves these problems. The apparatus, first and foremost, should allow for repeatability of ankle mobilization from one physical therapy practitioner to the next, one mobilization to the next and, one patient to the next.
It is desirable to provide a method and apparatus, which allows mobilizations on patients in the seated or standing position.
It is desirable to provide a method and apparatus, which allows the patient to apply force, and the resulting glide, to himself or herself. This enables maximum force and glide, without pain because the patient judges the pain intensity for himself or herself eliminating the possibility of increased and prolonged pain and delayed recuperation.
It is desirable to provide a method and apparatus, which after several supervised mobilization sessions, the physical therapy practitioner can specify the apparatus settings for the next session and the patient can be easily taught to perform the mobilizations, unassisted. This leads to the next, logical, step i.e. allowing a patient to take an apparatus home and perform mobilizations on himself or herself. It is therefore desirable that the apparatus be small and light enough to be easily transported by the patient.
It is desirable to provide a mobilization apparatus, which allows the patient to apply the treatment; thus freeing all those involved in the treatment from a very time-consuming task.
USPTO Backgrounds
USPTO Backgrounds