//

MCP joint fusion of thumb (tension band wiring technique)

    Overview

    Learn the MCP joint fusion of thumb (tension band wiring technique) surgical technique with step by step instructions on OrthOracle. Our e-learning platform contains high resolution images and a certified CME of the MCP joint fusion of thumb (tension band wiring technique) surgical procedure.
    The thumb consists of three joints; the carpometacarpal joint(basal joint), metacarpophalangeal joint and the interphalangeal joint. Whilst the basal joint is a saddle joint which allows movements in multiple planes, the other two are hinge joints which allow flexion and extension. The metacarpophalangeal (MCP) joint provides stability for pinch grip. The range of movements of this joint do vary between individuals and in some people the joint has very limited natural flexion.
    This joint can be effected be trauma and degenerative conditions. One common traumatic pathology which can lead to degenerative joint change here is injury to the ulnar collateral ligament which in the acute setting is called ‘Skier’s thumb’. If diagnosed in time this ligament can be repaired. Chronic laxity of the ligament due to repeated stressing is known by the eponym ‘Game-keeper’s thumb.’
    The common degenerative pathologies effecting the MCP joint are osteoarthritis and rheumatoid arthritis. In osteoarthritis the joint develops inflammation and stiffness and commonly remains fairly well aligned. In contradistinction with rheumatoid arthritis complex deformity ranging from a Boutonniere to a Swan neck deformity can be associated with the degenerate joint.
    The most definitive end stage surgical treatment for pathological conditions that result in severe MCP joint degenerative change (with or without deformity) is fusion. High levels of function can be expected as long as the remaining joints are functioning well. Replacements, though a technical possibility, have a tendency to early failure and sub-optimal function due to the high functional requirements of the thumb MCP joint.
    There are several common methods for fixing an MCP joint fusion including K-wires, tension band-wiring, screw fixation alone and plate and screw fixation. Each of the techniques have their advantages and disadvantages.
    The case below illustrates the use of tension band wiring for performing a fusion of the MCP joint in a patient who has osteoarthritis and ulnar collateral laxity of the joint.

    Indications


    INDICATIONS
    The common indications for fusion of the MCP joint of the thumb are:
    Osteoarthritis
    Rheumatoid arthritis
    Other inflammatory arthritis such as Psoriatic arthritis
    Chronic ulnar collateral laxity
    Traumatic injury to the joint where the joint surface cannot be reconstructed

    SYMPTOMS & EXAMINATION
    A detailed history regarding the patient’s symptoms has to be elicited. The type and severity of pain and the functional limitations should be noted. History of previous treatment such as splints and intra-articular steroid injections should be asked. If these options have not been tried they can be offered to the patient.
    Examination includes the upper limb in general looking at movements of shoulder, elbow and wrist and specifically at the thumb MCP joint. Swelling and tenderness around the joint is noted. Laxity of the ulnar collateral ligament is checked. Movements of the CMC joint and IP joints are checked. The usual symptoms are pain and stiffness of the joint. The is worse on pinching using the thumb or making a making a fist indication that the pain is on loading the joint.
    IMAGING
    Investigation is mainly through imaging. Plain X-Rays are usually sufficient to diagnose arthritic changes. In early cases ultrasound scan and MRI can help to identify subtle changes.
    ALTERNATIVE OPERATIVE TREATMENT
    For fingers, MCP joint replacement remains an option using either Silicone implants or the Pyrocarbon implants. However for the thumb, joint replacements do not work well as the forces going through the joints are too much and the joints wear out quickly.
    Though Tension band wiring is chosen in this case there are alternative methods for fusing the MCP joint. These include plates and screws, headless compression screws, K-wires alone, staples and lag screws. My reasons for using Tension band wiring are that it has high union rates and that the metal work is not prominent as in plates.
    NON-OPERATIVE MANAGEMENT
    Splints and intra-articular steroid injections help in symptomatic management.
    CONTRAINDICATIONS
    The only absolute contraindication is an infection in the vicinity of the operation. Relative contraindications include co-morbidities which make anaesthesia risky.

    Setup

    The procedure can be carried out under Regional anaesthesia or General anaesthesia. The arm is positioned over a hand table with an upper arm tourniquet in place. A single dose of intravenous antibiotic is administered. Flucloxacillin 1gm is the antibiotic of choice and in patients allergic to Penicillin, Clindamycin 500mg in given.

    Operation – 1

    Hand is positioned on the table
    The thumb is positioned on the table. The site has been marked with an arrow.

    Incision is marked over MCP jointThe hand is positioned on a rolled up Huck towel.
    A longitudinal dorsal incision is marked over the MCP joint. The incision is centered on the joint line and extends about 2-3cm proximally and distally. The cross-hatchings on the incision help to align the edges during closure.

    After the tourniquet is inflated, incision is made using a No.15 blade.

    Dissection in the subcutaneous plane avoiding dorsal nerve branchesAs the incision is deepened it is important to try and avoid any branches of the superficial radial nerve supplying the dorsum of the thumb. A tenotomy scissors is useful too dissect the tissues and mobilise the nerve branches away.

    A self-retaining retractor is used to expose the deeper tissues. The extensor hood(1) can be seen. The Extensor Pollicis Brevis(EPB) is tendon is on the radial side and inserts into the base of the proximal phalanx. The Extensor Pollicis Longus tendon(EPL) is on the ulnar side.

    Access between EPL and EPB tendonsUsing the blade the extensor hood is split longitudinally between the EPL an EPB tendons.

    Joint capsule openedThe joint capsule is split vertically exposing the joint.
    The collateral ligaments on the radial and ulnar side are released by cutting at the insertion over metacarpal head using a No.15 scalpel. to expose the head of the first metacarpal and the base of the proximal phalanx. This does not pose any problems as the joint is going to be fused.

    This shows the ulnar collateral ligament before it is released.

    joint is prepared using bine nibblersThe joint is being prepared for the fusion. This can be done using an oscillating saw, bone nibblers or a burr. In the past I used a saw, but now I use bone nibblers and a burr. This has the advantage of maintaining the shape of the bone and not shortening it too much. The resulting cup and cone configuration of the joint after the cartilage is nibbled allows to position the bone ends at an appropriate angle.
    Here the bone nibbler used for nibbling the head of the metacarpal can be seen.

    While nibbling the cartilage it is important to take small bites using the nibbler. Otherwise the nibbler slips from the smooth cartilage surface.

    Part of the cartilage has been nibbled. The hard subcondral bone can be seen underneath. It is important to remove it exposing the cancellous bone.

    joint preparation completed using burrA fine round burr (size 2 or 3) is being used to remove some of the subchondral bone. While using a burr it is important to irrigate it to cool it down.

    The prepared head of the first metacarpal can be seen.

    The base of the proximal phalanx is prepared in a similar way. Here bone nibblers and used initially to remove the cartilage.

    A burr is used subsequently to remove the cartilage.

    The prepared base of the proximal phalanx can be seen.

    K-wire used to make the hole for the circlege wireThe joint is now ready for fixation. As the first step, a 0.9mm K-wire is passed transversely across the proximal phalanx. This is made about 2cm distal to the base of the proximal phalanx. This hole is for passing the 0.5mm stainless steel circlege wire used for the tension band technique.

    This shows the K-wire being passed.

    A 0.5mm circlege wire is passed through the hole made using the K-wire.

    The stainless steel wire is bent and held away from the field.

    Joint held reduced and K-wires passed across the jointThe joint is now held reduces at the chosen angle for fusion. Thumb MCP joint is usually fused at about 20-30 degrees of flexion. If the basal joint and interphalangal joints are mobile, then a lesser angle of 20 degrees is chosen. Otherwise more flexion is beneficial. A 1.1 mm K-wire is passed from the head of the metacarpal into the proximal phalanx. It is important that one drops the hand holding the K-wire driver which helps to pass the K-wire at an acute angle into the bone.
    There is an alternate technique for passing the K-wires which is the retrograde technique. In this technique the K-wires are passed from the joint surface of the metacarpal in a retrograde fashion first. Once both K-wires are passed in this fashion, joint is held reduced and the K-wires passed across the joint.
    However, I find the antegrade technique described here easier.

    The K-wire in place across the joint.

    A second K-wire is passed parallel to the first one.

    Tension band technique is performed.The stainless steel wire is twisted into a figure of eight shape and passed under the two parallel K-wires as shown.

    The ends of the wire are twisted as shown. The key to getting good compression is to twist the wires tightly. Tightening is done by holding the ends using a plier and twisting in a clockwise manner. Once the wire is tight it starts forming secondary coils, at which point it should be cut.

    Operation – 2

    The wire ends are held using pliers and tightened as shown.

    The end of the twisted wire is cut and folded as shown.

    The K-wires are bent as shown. The degree of bend should the same as the angle of fusion.

    The second wire is bent in a similar way.

    The wire ends are cut about 0.5cm long.

    Completed tension band technique can be seenThe cut ends are twisted down completing the tension band technique. The cut ends of the K-wires are sitting over the metacarpal heads and do not usually need to be impacted. They can be covered when the periosteum and capsule are sutured.

    Check X-Rays are taken to confirm the position of the wires.

    X-rays show a satisfactory position of the K-wires. The bone ends are compressed.

    Wound closure is done in layersThe wound is closed in layers. Periosteum and capsule are closed using 4-0 PDS sutures.

    The extensor tendon is repaired using 4-0 PDS continuous sutures.

    The skin is closed in layers using 4-0 Monocryl. The first layer is interrupted sutures through the dermis and the second a continuous intradermal suture.

    Completed wound closure can be seen.

    Dressings and backslab are appliedDressing are being applied. The first layer is a non-adherent dressing using Jelonet, followed by dressing gauze.

    Cotton wool a volar POP backslab and a crepe bandage are applied.

    Post Operative

    Patient is discharged home the same day with advise to elevate the arm in a sling for 24 hours. Patient is reviewed in the clinic in one week when the dressings are changed. A POP cast is used for 4 weeks extending from mid forearm to the middle of the proximal phalanx of the thumb, allowing interphalangeal joint movements.
    At 5 weeks, POP cast is removed and check X-Rays are taken to look for union. If there is no solid union, a hand based thermoplastic splint is provided for further support for another 4 weeks and check X-Rays taken again.
    Patients can get back to normal activities including driving at 6 weeks.
    If there is limited flexion of the interphalangeal joint, hand physiotherapy is started through active and passive mobilisation. If at the end of 6 weeks of hand therapy, there is no improvement, removal of the metal work used for fusion and an extensor tenolysis is performed.

    Recommended Reading

    Lutsky KF1, Edelman D1, Lebowitz C2, Matzon JL1, Beredjiklian PK1. Union Rates and Complications After Thumb Metacarpophalangeal Fusion. Hand (N Y). 2018 Jul 1:1558944718784025. doi: 10.1177/1558944718784025.
    There were 56 thumbs in 53 patients (42 women and 11 men) including 12 TBW and 44 PS. The mean age was 60.9 years, and follow-up was 32.4 months. Twenty-eight of 44 plates were nonlocking, and 16 were locking. Of the locking plates, 7 of 26 used all locking screws, and 9 of 26 had a combination of locked and nonlocked screws. The mean flexion angle for TBW was 16.5° and PS was 12.8°. The mean coronal angle for TBW patients was 4.0° ulnar and PS was 2.5° ulnar. The overall union rate was 95%. There were 12 complications, 9 in the PS group. The TBW complications were painful hardware requiring removal. Eight complications in the PS group occurred in patients with locked plates. Five of the delayed or nonunions occurred in patients with locked plates and 4 of these were in plates with all screws locked.
    Complications using PS or TBW are not infrequent. Alignment with both techniques is similar, but use of locked plates specifically increases the rate of delayed or nonunions. We do not recommend routine use of locked plates for fusion of the thumb MPJ.
    Hagan HJ1, Hastings H 2nd. Fusion of the thumb metacarpophalangeal joint to treat posttraumatic arthritis. J Hand Surg Am. 1988 Sep;13(5):750-3.
    Thumb metacarpophalangeal (MCP) fusion to treat posttraumatic arthritis is retrospectively reviewed in 18 patients, 16 of whom were examined and functionally tested, with an average follow-up of 18 months. All patients were satisfied. There was 100% fusion in an average of 59.9 days. Preoperative disabling MCP pain was present in all patients, and mild postoperative pain and difficulty in picking up small objects were present in 78%. Results did not depend on position of fusion or preoperative arc of MCP motion. Key pinch strength was significantly increased by fusion. Complications included four pin tract infections without sequelae and three cases of prominent tension band hardware, which were removed in two.
    Stanley JK1, Smith EJ, Muirhead AG. Arthrodesis of the metacarpo-phalangeal joint of the thumb: a review of 42 cases. J Hand Surg Br. 1989 Aug;14(3):291-3.
    42 arthrodeses of the metacarpo-phalangeal joint of the thumb in 34 patients have been reviewed at a mean of 22.5 months after operation. Where bone stock allowed, Omer’s chevron arthrodesis was used. 83% of these operations were judged to have been successful by our patients, most of whom were suffering from inflammatory joint disease. Some patients had very poor pinch pressures when reviewed, but only those with persistent instability or pain were disappointed. All arthrodeses were fixed in flexion; although the angle varied, no ideal position was identified.

    Tags:

    You might be interested in

    Dark mode powered by Night Eye