Device for the relief of the symptoms of thumb saddle joint disease from the degenerative, inflammatory and rheumatic categories.

Description

[0001] The invention relates to a device for alleviating the symptoms of a thumb saddle joint disease of the degenerative, inflammatory and rheumatic variety.

[0002] In particular, rhizarthrosis is a disease of the thumb's carpometacarpal joint, which can lead to nonspecific signs of wear and tear accompanied by a reduction in the cartilage layer of the joint, potentially progressing to its complete dissolution, accompanied by increasingly painful inflammation and tenderness. Furthermore, the capsuloligamentous structures are secondarily damaged and weakened.

[0003] Previously known treatment methods immobilize the joint, thereby more or less effectively preventing movements and stresses perceived as painful.

[0004] In DE 3006 362 A1 an invention consisting of two open bridges attached to the forearm is described, in which, among other things, the thumb is inserted into a sleeve extending to the end of the rail in such a way that the entire hand, including the wrist, is immobilized.

[0005] DE 3519493 A1 discloses a device for immobilizing the thumb's carpometacarpal joint, in which the thumb and hand are at least partially enclosed and fixed by a rigid molded body. Due to the anatomical shape of the splint, the hand remains in its natural position, thus immobilizing both the thumb's carpometacarpal joint and the thumb's metacarpophalangeal joint.

[0006] WO 2011 / 110420 A1 also claims a device whose purpose is to achieve a specific and complete immobilization of the thumb saddle joint and thus reliably prevent the painful movement of the joints affected by osteoarthritis.

[0007] DE 20 2006 011 664 U1 relates to a metacarpal-thumb orthosis for repositioning the metacarpal joint, comprising an elastic splint that can be applied to parts of the hand and at least one closure element, wherein the splint is open in its longitudinal direction and symmetrical overall, and a closure element is arranged in the thumb-side area and at least one closure element in the wrist-side area. The splint may be made of plastic.

[0008] German patent DE 195 11 116 A1 relates to a thumb orthosis consisting of a dimensionally stable molded body with an opening for the thumb to pass through. When the orthosis is applied, it surrounds the thumb over part of its length and can be attached to the hand. The molded body is designed as a closed ring that distally surrounds the area between the thumb and metacarpus and proximally surrounds the thumb in the region of the carpometacarpal joint. The ring provides surface support to the thenar eminence on its volar side. The ring may be made of thermoplastic material.

[0009] WO 2007 / 066367 A2 represents the closest prior art and relates to a thumb orthosis with a rigid metal support in an essentially Y-shape, comprising at least two lateral sections and a central, elongated section. The two lateral sections encompass the wrist, while the elongated section extends to the tip of the thumb and has an elongated and curved shape corresponding to the anatomical shape of the hand.

[0010] All inventions have the disadvantage that immobilizing the joint causes the capsule-ligament-muscle apparatus to weaken in a short time, resulting in a progressive restriction of mobility and an aggravation of pain symptoms.

[0011] Furthermore, the desired immobilization is only achievable if the splint, which is sometimes plastically deformable and thus anatomically adapted, tightly encloses the body parts to be immobilized. This impairs blood circulation and, as a result of localized pressure, causes sensitivity and chafing.

[0012] The immobilization almost completely prevents even light physical activity, and the pincer grip formed by the thumb and middle finger is significantly more difficult or even impossible.

[0013] DE 20 2012 009 952 U1 deviates from the aforementioned principles and not only immobilizes the thumb saddle joint, but also spreads it by means of a wing-shaped pad made of a compliant, padded material, which is glued into the anatomically adapted orthosis. Pressure on the tip of the thumb, such as occurs particularly during a pincer grip, is thus diverted via the anatomically shaped orthosis to the midhand, which in turn increases the pressure on the pad and progressively expands the rubbing joint surfaces.

[0014] This has the disadvantage that the thumb's carpometacarpal joint is firmly enclosed in a splint. The pressure exerted against the splint, which is further increased by the glued-in pad, can lead to localized pressure points and even pressure sores when wearing the device. Furthermore, adjusting the orthosis presents considerable difficulties because the pad only effectively separates the joint when precisely aligned; otherwise, it can even exacerbate the pain of the underlying condition.

[0015] The aim of the invention is to provide a device by which the arthritic thumb saddle joint is dynamically relieved, combined with the advantage that the capsule-ligament-muscle apparatus is challenged in its natural movement by constant tension and relaxation and therefore does not become slack.

[0016] The Fig. 1 u. Fig. 2 show the device, Fig. 3 u. Fig. 4 show the device in the applied state.

[0017] The invention consists of a rail ( Fig. 1 -Fig. 4 ), detachably fixable (5) to the patient's wrist on one side and below the first thumb joint of the affected hand on the other (3). It consists of a strengthened thermoplastic material that partially encloses the wrist (1), fits snugly against the palm (7) and terminates with a corkscrew-shaped left turn below the first thumb joint (2).

[0018] In its basic position, the splint is designed to accommodate the thumb in its natural resting position.

[0019] If the thumb is now moved towards the middle finger in a pincer grip, the thumb (2), which is fixed below the first thumb joint, tensions the splint (4) against the holder (1) attached to the wrist as a result of its radial movement and thereby lifts the carpometacarpal joint of the thumb minimally from its original position, creating a gap between the interlocking joint heads so that they rub against each other less strongly or not at all as a result of the movement, which is accompanied by a noticeable reduction in pain.

[0020] The effect is comparable when bending the first thumb joint: Due to the splint designed as a counterweight against the wrist, the enclosed thumb joint levers the thumb saddle joint minimally out of the joint socket, thus relieving pressure on the joint bones standing on top of each other.

[0021] Through the dynamic process of adapted pressure relief, the remaining capsular-ligamentous-muscular apparatus is continuously stressed and strengthened. A further advantage of the invention is that, due to the minimal material required, the wearing experience, particularly because of the minimal skin coverage, is perceived as pleasant and non-intrusive.

[0022] In a preferred embodiment, a pad is incorporated into the rail below the thumb base joint (6).

[0023] In a further preferred embodiment, the rail consists of perforated plastic.

Claims

1. Orthosis made of plastic, with an anatomically adapted splint (4), the splint (4) being detachably attachable to a right wrist and proximal to a thumb saddle joint of the diseased hand, characterised in that the splint (4) terminates below the first thumb joint, guided from radial to ulnar and from dorsal to volar over the ball of the hand (7) with a corkscrew-shaped left-hand turn in the distal direction towards the first thumb joint.

2. Orthosis according to claim 1, characterised in that a padding is incorporated into the splint (4) for contact proximal to the thumb saddle joint.

3. Orthosis according to claim 1 or 2, characterised in that the orthosis can be formed from a perforated plastic.

4. Orthosis according to one of the preceding claims, characterised in that the splint (4) consists of a thermoplastic synthetic material.

5. Orthosis according to one of the preceding claims, characterised in that the splint (4) is designed to partially enclose the wrist.

6. Orthosis according to one of the preceding claims, characterised in that the splint (4) is shaped to accommodate the thumb (2) in its natural resting position.

7. Orthosis according to one of the preceding claims, characterised in that the splint (4) surrounds the thumb joint and is designed as an abutment against the wrist and, when applied, lifts the thumb saddle joint out of the joint cavity.