The following video will demonstrate the technique of total wrist arthroplasty including indications, contraindications, surgical technique, complications, and long-term outcomes. Wrist arthroplasty is indicated for the management of wrist pain and functional impairment resulting from rheumatoid, osteo, or post-traumatic arthritis. When considering wrist arthroplasty, other options such as wrist denervation, proximal row carpectomy, and partial or total fusion must also be discussed with a patient. Wrist arthroplasty is contraindicated in cases with significant bone loss, especially involving the capitate, evidence of weakness or paralysis of the wrist extensors, and evidence of active infection or significant florid synovitis. Most current third-generation wrist implants consist of a metal carpal plate fixed with screws to the distal carpal row, a metal stemmed radial component with an interpositioned polyethylene carpal ball of varying heights. These implants are porous coated to allow for cementless or cemented fixation. The case demonstrated in this video is that of a 77 year old right-handed retired gentleman with advanced osteoarthritis. Note involvement of both the radiocarpal and the mid carpal joints. After sterile preparation of the extremity and application of an exsanguinating tourniquet, the wrist is exposed to a dorsal longitudinal midline incision. The skin flaps are raised at the level of the extensor retinaculum, and the extensor retinaculum can be raised as a flap to be used for augmentation of the wrist capsule if necessary. The dorsal wrist capsule is elevated sharply of the distal radius as a distally based flap up to the level of the middle of the capitate. The interosseous ligaments on either side of the lunate are released and the lunate is excised. A 1.4 millimeter K wire is passed on either side stabilizing the scaphoid and triquetrum to the distal carpal row respectively. Placing the K wires dorsal to the digital extensor tendons will also protect the tendons throughout the procedure. The size of the implant to be used is determined by the carpal implant. The carpal scissor is centered over the capitate and the size is selected based on the line corresponding to the tip of the hamate. In this case a size 2 implant will be used. A guide wire is now inserted into the center of the capitate utilizing the modular drill guide placed over the head of the capitate with the saddle on the third metacarpal. Interoperative imaging should be utilized to confirm central placement of the capitate wire. The center of the capitate is drilled to the appropriate level using a laser marked cannulated 3.5 millimeter drill. A carpal guide bar is inserted into the capitate and the carpal resection guide is mounted. A hamate feeler is inserted into the carpal guide and the guide is positioned so that the hamate feeler closely abuts the tip of the hamate. This step ensures appropriate resection of the distal carpal row. The guide is pinned to the carpus and an oscillating saw is used to make the carpal resection. In order to accommodate the stem of the carpal plate the hole in the capitate is widened with the appropriate sized carpal broach. A size 2 trial carpal plate is then inserted and firmly seated using the carpal plate impactor. The plate is left in place during preparation of the distal radius. A size 2 right radial template is lined with the dorsal and radial edges of the distal radius and the center point of the radial canal is marked. This starting point is usually just Palmer and ulnar to Lister's tubercle. Using the starting point and the modular drill guide a 1.4 millimeter K wire is passed into the center of the distal radius. Central position of the guide wire should be confirmed by intraoperative fluoroscopy in two planes. A 3.5 millimeter cannulated drill is used over the guide wire to create a channel for placement of the intramedullary guide rod into the radius. Fluoroscopy is utilized to confirm central placement of the intramedullary guide rod. The size 2 radial resection guide is mounted over a radius filler that has been placed over the guide rod. Appropriate level of radius resection is determined by the laser mark on the radius filler. The ulnar most cut of the distal radius is marked with the oscillating saw using the radius score guide. This is necessary to prevent violation of the distal radial ulnar articulation. Distal radius resection is performed using an oscillating saw. In order to preserve cortical integrity of the distal radius especially in dense bone, drill holes are first made in the radius. The IM rod is reinserted and the radius guide is slid over the rod and aligned in the correct rotation with the distal radius. This line is marked on the dorsum of the radial cortex. Two drill holes are made using a four millimeter stop drill. The box punch for the right side is then slid over the rod. It is lined with a correct rotation and then impacted with a mallet until it sits flush with the distal radius. Dense subchondral bone left behind by the box punch is excised. The distal radius is serially broached first with a size 1 and then the size 2 broach. Care is taken to ensure correct rotational and longitudinal alignment of the broach. A size 2 radial trial implant is then inserted and impacted with a radial impactor. The standard carpal poly trial is placed over the carpal plate and wrist stability is tested. It should be possible to move the wrist at least 35 degrees in either direction. If unstable a larger carpal poly may be trialed. If cemented fixation is planned additional broaching of the distal radius and widening of the carpal canal are necessary. Bone debris are removed by irrigation, cement is injected and the radial and carpal components are seated. The definitive carpal implant is first inserted and firmly seated with an impactor. The modular drill guide is placed over the radial hole of the carpal plate with the saddle overlying the index metacarpal. A 1.4 millimeter k-wire is inserted in the guide into the index metacarpal and the position is confirmed on fluoroscopy. The k-wire sleeve is then removed and the intended depth of the screw is measured. A 4.5 millimeter screw is inserted after drilling with a 2.5 millimeter cannula drill bit. Using a similar technique the ulnar screw is inserted into the hammate. Both screws are tightened until the carpal plate is secured in position. While the radial screw may extend into the index metacarpal the ulnar screw should not extend into the carpal metacarpal joint. A locking cap is placed over each screw to create a locked screw construct. Prior to insertion of the radial component non-absorbable sutures are passed through the distal radius for capsular closure. The radial component is then inserted and firmly seated with an impactor. The carpal poly is then placed over the carpal plate and impacted into position. Cancellous bone is impacted in the distal carpal row to create a fusion. After checking stability the dorsal capsule is repaired and the extensor retinaculum is replaced. The extensor pollicis longus tendon may be placed subcutaneously. The tourniquet is released prior to definitive closure and a drain may be placed subcutaneously. The wrist is immobilized postoperatively for a period of 10 to 14 days until the sutures are removed. Active movement of the wrist is then encouraged out of a removable splint. The splint is weaned after four weeks and the patient is encouraged to use the hand and wrist as much as possible with a strengthening program beginning around six weeks. Postoperative X-rays demonstrate stable position of the wrist and appropriately sized and positioned radial and carpal implants. These pictures demonstrate the range of motion of the patient six weeks after surgery. The following is an example of a wrist replacement for a patient with rheumatoid arthritis and carpal subluxation. A CT scan of the wrist is helpful to fully understand the extent of carpal subluxation and to ensure there is enough preservation of the capitate to allow for implantation of the carpal stem. At surgery the lunate is first excised and then the proximal part of the scaphoid is also removed with the saw so as to allow better exposure of the proximal capitate pole. Note the capitate is subluxated in a volar direction and sits along the volar edge of the distal radius. Using blunt dissection techniques the distal carpal row is mobilized by elevating the contracted soft tissue and the capsule of the distal edge of the radius and the distal carpal row until the capitate can be fully delivered dorsally into the wound. The rest of the procedure is performed as demonstrated earlier. This patient with old, burned out rheumatoid arthritis presented with pain at the distal radial ulnar joint and a wrist that was auto-fused in a position of radial deviation and palmar flexion. Patient had significant functional impairment and could not use their hand for gripping or fine dexterous tasks. The patient was able to demonstrate good isometric contraction of wrist extensors. A wrist arthroplasty was performed by creating an osteotomy through the fusion under radiographic control. Additionally a DARA resection of the distal ulnar was performed to address the arthritic distal radial ulnar joint. Like any other joint replacement surgery, wrist arthroplasty also can have complications such as wound breakdown or hematoma formation and post-operative infection. Dislocation is less common with 3rd generation implants but loosening in the long term is possible especially in the carpal component. Angel Ferreres and colleagues reported their outcome of 21 universal 2 wrists implanted in patients with rheumatoid and osteoarthritis. They had one hematoma, one infection and one case of carpal loosening at a follow up between 3 to 8 years. The average arc of motion of the wrist was 75 degrees and 17 patients remained pain free at final follow up. In a registry of 215 patients who underwent the SBI re-motion wrist arthroplasty, Herzberg and colleagues noted a complication rate of 5% in rheumatoid and 6% in non-rheumatoid wrists. The overall survival was 96% and 92% for rheumatoid and non-rheumatoid respectively and loosening was observed in 4 and 3% and an improvement in DASH was noted in 26 and 21% of patients respectively. To summarize, good outcomes can be expected with 3rd generation wrist replacement implants due to the low dislocation and loosening rates. Current instrumentation allows reproducible implantation. Wrist replacement should be part of a hand surgeon's treatment algorithm when managing wrist arthritis.

total wrist arthroplasty

indications

surgical technique

complications

third-generation wrist implants