Arthrodesis

Cure Arthritis Naturally

Cure Arthritis Naturally

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For years, arthrodesis has been the gold standard in treating isolated end-stage MP arthritis, whether inflammatory or post-traumatic arthropathies [25]. Arthrodesis is able to provide effective pain relief as well as restore stability to the joint, even in the setting of severe arthritis. [1,3,7,10,25]. The key to why MP fusion in the thumb is so successful lies in the relatively negligible loss of motion that results from MP fusion. The functional goal of the thumb is to be able to oppose to at least the ring finger, or preferably the small finger. Because the CMC joint of the thumb has many degrees of freedom, even with a fused MP joint, patients are still able to oppose the tip of the thumb to the tip of the ring or small finger; thus fusion of the MP joint is able to eliminate pain, while affecting thumb biomechanics at a minimal level.

The goal of arthrodesis is to be able to allow union at a biomechanically functional position for the patient [26]. Several authors estimate this position to be roughly 15° of flexion, whereas minimal variation exists in the recommendation of both internal/external rotation and radial/ulnar deviation. By establishing fusion at the MP joint, the surgeon is also able to potentially save involvement of other joints of the thumb [25]. For example, by fusing the MP joint between 20° and 40° of flexion, stress can be relieved from the CMC joint by minimizing the activity required at the CMC for thumb opposition. This position not only provides better pain relief in patients who have an already arthritic CMC, but also protects it from worsening arthritis [25].

Many MP arthrodesis techniques have been described [1,3,5,10,16,22,26]. All procedures, however, can be divided into two key components:

(1) metacarpal/proximal phalanx osteotomy, and

(2) bone fixation. In joint fusion, there are two main types of osteotomies currently used:

(1) a flat cut at the desired angle of fusion, and

(2) the shallow V or "chevron" osteotomy. The latter type allows both bone fragments to fit together, preventing them from sliding from the position of fixation, but it needs more precision cuts to accomplish the desired angle. Both types of osteotomies work relatively equally, so the type of osteotomy performed usually depends on the surgeon's preference.

Numerous methods of fixation have been performed over the years, ranging from Kirschner-wire to cannulated screw fixation. The technique described by Omer [27] in 1968 is the most widely used [3]. In this procedure, a posterior approach to the joint is established, and the extensor mechanism is divided at the MP joint, with consequent release of the collateral ligaments from the meta-carpal [27]. After appropriate exposure of the joint is obtained, the joint surfaces of the metacarpal and proximal phalanx are osteotomized to generate a chevron-shaped mortise (Fig. 5) with the point oriented proximally. This osteotomy allows for the placement of the joint at the desired angle. Once both surfaces are opposed and desired functional orientation is acquired, stabilization is achieved by the placement of Kirschner wires to hold fixation. Soft-tissue release of thumb web is done whenever necessary [3].

This procedure has been relatively successful. Stanley and colleagues [3] studied 42 arthrodeses

Chevron Osteotomymis

Fig. 5. Chevron osteotomy as described by Omerin 1968. Metacarpal and proximal phalanx are cut in a shallow V fashion. Metacarpal is inclined volarly to give desired angle of fusion. Once the two bones are approximated, fixation is accomplished by placement of two crossing Kirschner wires. (From Omer GE Jr. Evaluation and reconstruction of the forearm and hand after acute traumatic peripheral nerve injuries. J Bone Joint Surg Am 1968;50(7):1469; with permission from the Journal of Bone and Joint Surgery, Inc.)

Fig. 5. Chevron osteotomy as described by Omerin 1968. Metacarpal and proximal phalanx are cut in a shallow V fashion. Metacarpal is inclined volarly to give desired angle of fusion. Once the two bones are approximated, fixation is accomplished by placement of two crossing Kirschner wires. (From Omer GE Jr. Evaluation and reconstruction of the forearm and hand after acute traumatic peripheral nerve injuries. J Bone Joint Surg Am 1968;50(7):1469; with permission from the Journal of Bone and Joint Surgery, Inc.)

with the Omer technique, and followed up for an average of 22.5 months postoperatively. Eighty-three percent of fusions were reported as successful in pain reduction and return to activity. Mean angle of fusion was 11.5° of flexion. The main indication for arthrodesis reported in this study was pain. In 36% of hands reviewed, MP arthrodesis was supplemented by other procedures. There were five nonunions (12%). The angle of fusion, which ranged from 0° to 20° flexion, was shown not to correlate with the patient's ability to oppose the thumb, nor was it related to the amount of pain reported in the postoperative follow-up. Two major complications were reported from this procedure. Both were extensor pollicis longus (EPL) tendon ruptures as a result of longitudinal wires placed during fixation.

The observation that compression at a fracture or osteotomy site helps achieve union served as the basis for the introduction of tension band arthrodesis. In the finger, the power of the flexors far exceeds that of the extensors [28]. Tension band arthrodesis uses this concept to turn the force of flexion into a force of interfragmentary compression, and thus aid the process of union (Fig. 6). The added benefit of this procedure over conventional Kirschner-wire fixation is its ability to provide compression of bone opposition at the osteotomy site and relieve stiffness from other joints by allowing early movement [26].

Feldon and coworkers [25] and Inglis and Hamlin [10] advocate for fusion at 15° flexion, 15° abduction, and 15° internal rotation. They also stress that this not a fixed rule, because the other joints must also be taken into consideration. For example, if the CMC joint contains significant pathology, MP joint should be fused in more flexion, as much as 25° [25]. Increased flexion at the MP joint when the CMC is compromised allows the thumb tip to approximate the ring or small finger. If CMC is diseased and MP joint is fused at too shallow of an angle, thumb opposition will be compromised and subsequent discomfort and disability will ensue.

Tension band has been shown to be more effective than conventional Kirschner-wire fusion of the MCP joint alone [10,26]. In one study [26], 203 MP and IP arthrodesis were reviewed comparing tension-band to Kirschner-wire only fixation. Infection rates were found to be much higher in the Kirschner-wire than in the tension-band group (18% versus 2% respectively). Of these infections in the Kirschner-wire group, 42% lead to a nonunion at the MCP joint. Rearthrodesis rates for

11 II 11 II

Ligament Tension Screw
Fig. 6. Tension band technique. (A) Dorsal view. (B) Lateral view. (From I Jsselstein CB, van Egmond DB, Hovius SE, et al. Results of small-joint arthrodesis: comparison of Kirschner wire fixation with tension band wire technique. J Hand Surg [Am] 1992;17(5):953; with permission.)

over the guide wire and a 3.0-mm screw is then secured (Fig. 7).

One study in 2004 [5] looked at the cannulated screw procedure in 26 patients. Their indications for surgery were instability, chronic instability, inflammatory arthritis, and fixed boutonniere. Twenty-five of 26 patients achieved both clinical and radiographic fusion, and reported pain relief as well as return to daily activities. Average time to union was 10 weeks, with a mean fusion angle of 18°. At an average of 32 months, (range 21-44 months) there was one nonunion that was achieved fusion via tension band. There were no reported infections or need for removal of hardware.

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Arthritis Joint Pain

Arthritis Joint Pain

Arthritis is a general term which is commonly associated with a number of painful conditions affecting the joints and bones. The term arthritis literally translates to joint inflammation.

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