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Severe wrist arthritis is most commonly treated by complete wrist arthrodesis,1-3 which provides predictable pain relief but the loss of motion may reduce ease of function.4 In selected patients, motion preserving surgical options, including limited intercarpal fusion, proximal row carpec-tomy (PRC), and total wrist arthroplasty (TWA) are considered. However, limited fusion and PRC are typically possible only in less severe cases in which there are some articular surfaces showing minimal degeneration that can be retained.5
TWA is an option for patients who have lower activity demands and specific needs or desires to maintain some wrist motion.1,3 Recent utility and decision analysis studies6,7 demonstrate that arthroplasty is associated with higher qualify adjusted life year (QALY) than arthrodesis in patients with rheumatoid arthritis. Despite these positive aspects of TWA, the procedure is not as widely accepted as hip, knee, or shoulder arthroplasfy. Early implants had problems related to both materials and design, with breakage, loosening and joint imbalance being common complications.8 Newer generation implants are improved with more predictable early function, less joint imbalance, and rare breakage, but distal component loosening remains a substantial problem. Thus, patients with poor bone stock and those with high activity demands are typically not candidates for TWA, and all patients are advised to restrict activities to reduce the risk of implant loosening.9,10
A new motion preserving procedure has recently been used at our institution in selected patients with severe arthritis who do not qualify for TWA but request an alternative to complete wrist fusion. In this procedure, a distal radius implant arthroplasty is combined with a PRC. The distal radius component of a Universal 2 (UNI 2) total wrist arthroplasty system (Integra life Sciences, Plainsboro, NJ) is used. To our knowledge, there have been no previous publications on this tech-nique. We report our first two cases which have shown a satisfactory early outcome for pain relief and functional wrist motion.
KW is a 36-year-old female with a 15 year history of rheumatoid disease who presented with bilateral wrist arthritis causing pain and deformity. The left wrist was more painful than the right. She is currently taking Azathioprine and daily prednisone, which has stabilized her arthritis. She had undergone a previous right wrist extensor tenosynovectomy and a left long finger bou-tonniere reconstruction. Despite trials of splinting and intra-articular steroid injections, she continued to have pain in her wrists.
Examination of the two wrists was nearly equivalent showing bilateral volar wrist subluxation and ulnar deviation. Range of motion of the more painful left wrist was 50° of flexion and 45° of extension with full pronosupi-nation. Her resting posture showed approximately 20° of ulnar deviation. She could radially deviate to neutral but was unable to achieve additional ulnar deviation. The distal ulna was severely subluxated dorsally. Preop-erative radiographs in Figures 1A and and1B1B show severe arthritis with volar subluxation of the carpus and dorsal subluxation of the ulna but the capitate head appeared to be preserved.
Surgical options of complete wrist arthrodesis, total wrist arthroplasty, and distal radius implant arthroplasty with proximal row carpectomy were discussed with the patient. Due to her young age and relatively active life style she was not a good candidate for total wrist replacement. She was quite concerned that her function would be substantially limited by bilateral wrist fusions based on her experience using wrist splints. Thus she chose to proceed with distal radius implant arthroplasty combined with proximal row carpectomy.
The operation was performed under regional anesthesia and tourniquet. A dorsal longitudinal incision was made. The extensor retinaculum was raised as a radially based flap and a tenosynovecotmy was performed. The extensor tendons were mobilized both radially and ulnarly. The dorsal wrist capsule was raised as a dis-tally based flap. The proximal carpal row was severely malaligned and arthritic but the capitate head cartilage was in good condition. The lunate fossa showed arthritis with erosions. The distal radioulnar joint was arthritic and subluxated and the decision was made to perform a Darrach resection of the distal ulna. A distal radius component of the Universal 2 total wrist replacement system (Integra Life Sciences, Plainsboro, NJ) was implanted as described previously.8 An intraoperative photo is shown in Figure 1C. The capsule and retinaculum were reap-proximated. The skin was closed over a subcutaneous suction drain. A fluff dressing and wrist splint was applied. Her drain was removed, and she was discharged on the second post-operative day.
Her post-operative course was uneventful. She continued on prednisone and other rheumatoid medication without interruption. The wound had some slight superficial dehiscence at the two-week post-operative follow up and thus the sutures were retained for an additional week. She was transitioned to a removable splint and started on gentle wrist motion. At three weeks, the wound was healed and her pain was minimal. At four months she was pain free in her left wrist and back to her preoperative activity level including gardening. Wrist range of motion was 50° flexion, 30° extension, 5° radial deviation, and 15° ulnar deviation. At one year follow up the motion was unchanged.
At the time of this report, she is two years out from the procedure. The follow up radiographs are in Figures 1D and and1E.1E. Wrist range of motion had remained fairly stable with small gains in radial and ulnar deviation. Because of the good response to the procedure on the left wrist, she elected to have the same procedure on the right wrist. She is pleased with the early results of the right wrist.
LD is a 52-year-old right hand dominant male who presented with over a year and a half of right wrist pain. Initially his pain was aggravated by repetitive and stressful activities such as shoveling and heavy lifting but gradually the pain escalated despite anti-inflammatory medications, splinting, and a change in life style. He began to have pain with activities of daily living (ADL), such as note-taking during classes that he was taking to pursue a less physically strenuous new career.
In 2000, he had a left partial wrist arthrodesis for osteoarthritis that provided good pain relief but very limited motion. He has osteoarthritis of both knees and smokes about one pack per day. His medical history is otherwise unremarkable. Physical examination showed 30° flexion, 40° extension, 5° radial deviation, 25° ulnar deviation, 60° supination, and 80° pronation. Radiographs (Figures 2A, ,2B)2B) demonstrated severe radiocarpal arthritis.
He sought relief for pain in the right wrist but wished to retain as much motion as possible in this dominant wrist, in particular because of the minimal motion he had in the left wrist. We had a discussion about the surgical options similar to the first patient (KW). The plan was to perform an intra-operative assessment after completing a proximal row carpectomy to determine the condition of the capitate head and the lunate fossa. If these surfaces showed substantial degeneration then a distal radius implant would be inserted.
Surgical exposure was performed using the same technique as described for the first case. Intra-operative findings showed substantial arthritis involving the lunate fossa and mild degeneration of the capitate head. The decision was made to insert a distal radius implant. Passive motion in the operating room was 35° each of flexion and extension after closure.
He was placed in a splint and discharged from the hospital after an overnight stay. Sutures were removed at two weeks and a removable splint was applied. He was instructed in gentle range of motion exercises. At six weeks after surgery, he had complete relief of wrist pain and had progressed to using this wrist for all activities of daily living. At three months after surgery active wrist range of motion was 30° flexion, 39° extension, 31° ulnar deviation, 5° radial deviation, 90° pronation, and 80° supination. He was bearing weight on the wrist intermittently during crutch walking due to knee pain at that time. At one year follow up he has no wrist pain and the motion was maintained. The one-year post-operative radiographs are shown in Figure 2C and and2D.2D. Some erosion of the hamate has occurred which is likely due to impingement from the implant in ulnar deviation.
Treatment options for severe wrist arthritis are limited, particularly in physically active patients. Traditional motion preserving procedures are best suited for patients in whom the degeneration spares the lunate fossa because this optimizes the potential outcome following a proximal row carpectomy or scaphoid excision with intercarpal fusion.5 Total wrist arthroplasty can be considered but the risk of distal component loosening precludes this option in younger or active patients.9,10
When selecting a procedure the expected range of motion should be sufficient to make it more beneficial than total wrist arthrodesis, which usually provides a predictable result for pain relief and durability.13,11 Functional wrist range of motion can be defined in three different ways: full normal motion, the motion used by individuals with normal wrists during routine activities, or the minimum range needed to perform activities. Normal wrist range of motion as defined in the American Medical Association Guidelines to the Evaluation of Permanent Impairment is 60° flexion, 60° extension, 30° ulnar deviation, 20° radial deviation, 80° pronation, and 80° supination.12 Although several studies have tried to define what constitutes functional wrist motion by measuring the ranges used by normal volunteers to perform activities of daily living,13,15 there is no consensus of opinion. Another study4 used standardized tests and volunteers to perform tasks at different motion-restricted states. Subjects were able to perform the tasks regardless of the degree of wrist motion limitation. However, performance was significantly worse for the motion-restricted state.
A recent article16 reviewed the results of several published studies on total wrist arthroplasty and arthrodesis in rheumatoid patients. The authors chose to use the definition of functional as reported by Palmer et al.14 of 5° flexion, 30° extension, 10° radial deviation, and 15° ulnar deviation. The authors claimed that three of the eighteen studies on total wrist arthroplasty reported motion in the functional range following wrist replacement. Our patients achieved functional range of motion and were equal to or better than total wrist patients.
PRC has been used to treat non-inflammatory arthritis of the wrist for many years. Recent 10 year follow up studies17,18 of PRC show high satisfaction rates for pain relief and most patients obtain functional motion. In nearly all of these patients there was radiographic evidence of radiocapitate arthrosis at follow up but its presence did not correlate with greater clinical symptoms. However, the lunate fossa and capitate head were not degenerated at the index operation in these patients. Other reports found poor outcomes after PRC in patients with degenerative changes of the lunate fossa or capitate head.5,19 A 41 month follow up study of eight patients with degeneration of the lunate fossa and or capitate head who were treated by PRC with capsular interposition showed good pain reduction, functional motion, and unchanged grip strength.19 Both of our patients had substantial degeneration of the lunate fossa, one had early degenerative changes of the capitate head, and the other had radiocarpal subluxation and thus we believe they were not good candidates for PRC alone.
Our patients have complete pain relief at one year. Their wrist range of motion is functional and very acceptable to them. This novel technique was successful in the treatment of both osteoarthritis and inflammatory arthritis however both patients had good bone stock and soft tissue quality. Similar to traditional PRC, some degeneration of the capitate head is likely to occur but it may well remain asymptomatic as seen in our second patient. Based on these early results, we believe distal radius implant arthroplasty combined with PRC is an option for carefully selected patients who would otherwise only be eligible for complete wrist arthrodesis.
Dr. Adams has received a research grant from KMI.