 |
 |
 |
|
| home | CME | help | feedback | subscriptions | archive |
|
© 1996 The Journal of Bone and Joint Surgery, Inc. Results of Total Elbow Arthroplasty after Excision of the Radial Head and Synovectomy in Patients Who Had Rheumatoid Arthritis*  , BOSTON, MASSACHUSETTSInvestigation performed at the Department of Orthopaedic Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston
We compared the results of twenty-three consecutive capitellocondylar total elbow arthroplasties in twenty-three patients in whom an excision of the radial head and synovectomy for rheumatoid arthritis had failed with those of twenty-three non-consecutive primary capitellocondylar total elbow arthroplasties in twenty-three patients who had rheumatoid arthritis. The two groups were matched for age, gender, duration of follow-up, side of the operation, type of prosthesis, and operative approach. The average duration of follow-up was four years (range, two to fourteen years). At the most recent follow-up examination, use of a 100-point rating system demonstrated an improvement from an average preoperative score of 21 points (range, 12 to 42 points) to an average postoperative score of 87 points (range, 17 to 97 points) for the group in whom an excision of the radial head and synovectomy had failed. The group that had primary arthroplasty demonstrated an improvement from an average preoperative score of 22 points (range, 7 to 42 points) to an average postoperative score of 94 points (range, 85 to 100 points). The group that had primary arthroplasty had a significantly greater improvement in terms of relief of pain (p < 0.05), functional status (p < 0.01), and the elbow-rating score (p < 0.03) than the other group. Four patients who had had failure of an excision of the radial head and synovectomy and none of those who had primary arthroplasty needed an additional operative procedure. Six of the patients who had had a failed excision and synovectomy and none of the patients who had primary arthroplasty had instability of the elbow components. We concluded that, although excision of the radial head and synovectomy is a conservative and effective method of treating a painful rheumatoid elbow, conversion to a capitellocondylar total elbow arthroplasty is more difficult after such an operation and the results at a minimum of two years are inferior to those for primary capitellocondylar total elbow arthroplasty.
Arthroplasty procedures have been used to improve function and to relieve pain in the elbow of patients who have rheumatoid arthritis4,7,8,10,12. Excisional arthroplasty has produced good functional results in patients who have an early stage of the disease2. Excision of the radial head combined with synovectomy has been the most widely used procedure in the operative treatment of painful elbows in patients who have an early stage of rheumatoid arthritis1,13. However, patients who have a later stage of rheumatoid arthritis may need replacement arthroplasty for relief of pain and improvement of function3,7,10. The capitellocondylar total elbow implant was one of the first unconstrained prostheses to be used in a total elbow arthroplasty3,4,14,15,17. Previous studies4,14 of such implants have shown few instances of mechanical loosening, as well as an improvement in the categories of relief of pain, functional status, and range of motion4,14. However, little attention has been directed to the result of capitellocondylar total elbow arthroplasty in patients who had previous excision of the radial head and synovectomy. The purpose of the present study was to determine the results of total elbow arthroplasty after such a procedure in patients who had rheumatoid arthritis.
We reviewed the results of twenty-three consecutive capitellocondylar total elbow arthroplasties that had been performed between 1975 and 1990 at the Robert Breck Brigham and Brigham and Women's Hospitals on twenty-three patients in whom an excision of the radial head and synovectomy had failed (Group 1). Those results were compared with the results of twenty-three non-consecutive primary capitellocondylar total elbow arthroplasties performed at the same institutions and during the same time-interval on twenty-three patients (Group 2). The primary diagnosis was rheumatoid arthritis in all forty-six elbows. The groups were matched according to age, gender, side of operation, duration of follow-up, type of prosthesis, and operative approach. The matching process was performed randomly and in a blinded fashion in order to avoid selection bias. All of the patients were followed clinically and radiographically for at least two years after the operation. The average duration of follow-up was four years (range, two to twelve years) in Group 1 and four years (range, two to fourteen years) in Group 2. At the time of the arthroplasty, the average age was fifty-four years (range, thirty-two to seventy-one years) in Group 1 and fifty-five years (range, thirty-two to seventy-three years) in Group 2. In each group, there were six men and seventeen women as well as involvement of nine left elbows and fourteen right elbows. For all of the patients, the indications for implantation of the prosthesis were intractable pain, a limited range of motion, radiographic evidence of destruction of the joint, and osseous anatomy that was sufficient to support the implant. A capitellocondylar prosthesis was used in all of the patients. From 1975 through 1977, three elbows in each group were replaced by an all-plastic ulnar component through a posterior operative approach; in 1978, one elbow in each group was replaced by a metal-backed ulnar component through a posterior approach; and after 1979, nineteen elbows in each group were replaced by a metal-backed ulnar component through a modified Kocher approach6. The humeral component was the same in all patients. Both components were inserted with cement in each patient in both groups. The operative technique, including that used for the insertion of the capitellocondylar total elbow replacement, has been previously described4. The postoperative regimen was the same in both groups4. In Group 1, the excision of the radial head and the synovectomy had been done an average of six years (range, one to eighteen years) before the total elbow arthroplasty. No other previous operative procedure had been performed on any patient in either group. At the follow-up examination, the elbow was evaluated with use of a 100-point rating system4 in which pain was assigned 50 points; function, 30 points; motion, 10 points; flexion contracture, 5 points; and cubitus valgus alignment, 5 points. The functional evaluation, which was limited to the involved elbow, included six categories: no limitations, slight restriction of activities of daily living, unable to lift objects weighing more than ten pounds (4.5 kilograms), moderate restriction of activities of daily living, unable to comb the hair or touch the head, and unable to feed oneself. Standard anteroposterior and lateral radiographs were made of the involved elbow. The bone-cement interface for both the humeral and the ulnar component was divided into zones for the purpose of recording the location and extent of any reaction at that interface16. A humeral or ulnar radiolucent line was reported at the time of the latest follow-up if it had been seen in any zone on any postoperative radiograph. All of the radiographs were reviewed by one of us (E. H. S.). The over-all functional and radiographic results as well as the complications were assessed in each group. Statistical analysis of the outcome was performed with use of an unpaired t test. Differences between the two groups with regard to the development of complications or the need for a subsequent operation were assessed with use of chi-square contingency tables.
The average duration of follow-up was four years (range, two to fourteen years) for the entire series, four years (range, two to twelve years) in Group 1 (the patients who had had an excision of the radial head and synovectomy), and four years (range, two to fourteen years) in Group 2 (the patients who had a primary arthroplasty). The average scores4 for the elbows in Group 1 were 21 points (range, 12 to 42 points) preoperatively and 87 points (range, 17 to 97 points) at the time of the most recent follow-up. The average scores in Group 2 were 22 points (range, 7 to 42 points) and 94 points (range, 85 to 100 points), respectively. The patients in Group 2 had a greater improvement in the elbow-rating score (p < 0.03) than did those in Group 1. In Group 1, twenty-one patients had severe pain preoperatively and sixteen were pain-free at the time of follow-up. In Group 2, eighteen patients had severe pain preoperatively and twenty-one were pain-free at the time of follow-up (Table I). Over-all, pain relief was better in Group 2 (p < 0.05).
In Group 1, the average preoperative and postoperative ranges of motion of the elbow were 126.8 and 142.7 degrees of flexion, 29.8 and 24.7 degrees of extension, 61.7 and 69.7 degrees of supination, and 69.2 and 76.4 degrees of pronation, respectively (Table I). In Group 2, the average preoperative and postoperative ranges of motion were 120.6 and 143.5 degrees of flexion, 39.2 and 29.6 degrees of extension, 45.5 and 65.7 degrees of supination, and 59.3 and 73.3 degrees of pronation, respectively. In Group 1, the average gain in the arc of flexion and extension was 21.0 degrees, whereas the average gain in Group 2 was 2.5 degrees (p < 0.1). The average gain in the arc of supination and pronation was 15.2 degrees in Group 1, whereas it was 34.2 degrees in Group 2 (p < 0.08) (Table I). In Group 1, thirteen patients were severely or totally disabled preoperatively; at the time of follow-up, eleven patients had no functional limitations (Table I). In Group 2, ten patients were severely or totally disabled preoperatively; at the time of follow-up, twenty patients had no functional limitations. Over-all, the patients in Group 2 had a greater improvement in function (p < 0.01). At the latest follow-up examination, radiolucent lines were seen adjacent to two humeral components and to seven ulnar components in Group 1. Two of the three all-plastic ulnar components in this group were associated with radiolucency. The radiolucent lines adjacent to four of the seven ulnar components and to one of the two humeral components were one millimeter wide or less and were non-progressive. Radiolucent lines, all one millimeter wide or less and non-progressive, were seen adjacent to one humeral component and to two ulnar components in Group 2. Almost all of the lines adjacent to the ulnar components in both groups were located in the trochlear notch of the ulna.
The complications were classified as intraoperative, perioperative, and late postoperative. One intraoperative complication, a fracture of the medial epicondyle that was treated with open reduction and internal fixation, occurred in Group 1. After stabilization of the fracture, the prosthesis was inserted. There were no long-term problems related to this complication. The patients in Group 2 had no intraoperative complications. Perioperative complications in Group 1 included necrosis at the edges of the wound (one patient), transient sensory ulnar-nerve palsy (four patients), transient motor ulnar-nerve palsy (one patient), and instability of the elbow components with a condylar shift of the articulation where the components had slipped out of alignment (one patient). The transient sensory ulnar-nerve palsy was characterized by a tingling sensation along the little finger that lasted one or two days4. In Group 2, perioperative complications included a wound hematoma (two patients) and transient sensory ulnar-nerve palsy (five patients). Late complications in Group 1 included dislocation of the implant (three patients), instability with subluxation (two patients), loosening without infection (three patients), and permanent partial motor and sensory ulnar-nerve palsy (one patient). There was no relationship between the time from the excision of the radial head and the synovectomy to the arthroplasty and the presence of late complications. One of the three dislocations was treated with revision of the capitellocondylar components; one, with conversion of the prosthesis to a flexible hinge (triaxial) implant (Figs. 1-A, 1-B, and 1-C); and one, with soft-tissue reconstruction of the medial collateral ligament with a palmaris longus graft as well as advancement and repair of the triceps (Figs. 2-A, 2-B, and 2-C). The two patients who had instability and subluxation were asymptomatic, and no intervention was performed. One patient who had had loosening of the ulnar component without infection had a revision, and the other two patients who had loosening were not sufficiently symptomatic to want additional operative intervention. In the patient who had a permanent partial motor and sensory ulnar-nerve palsy, exploration, neurolysis, and anterior transposition of the ulnar nerve was performed. This patient had incomplete recovery of neurological function. Two patients in Group 2 had a permanent sensory ulnar-nerve palsy.
The rate of complications was lower for Group 2 than for Group 1. The number of patients who had postoperative instability of the elbow components was significantly greater in Group 1 than in Group 2 (p < 0.009). Instability of the elbow components developed in six patients in Group 1 (three had dislocation; two, instability with subluxation; and one, a condylar shift of the articulation) and in none of the patients in Group 2. Instability of the elbow components was also seen in two of the four patients in whom a posterior operative approach had been used. Significantly more secondary procedures were performed in Group 1 than in Group 2 (p < 0.04). Four subsequent procedures, which included revision of the elbow arthroplasty in three patients and a ligament reconstruction with transposition of the ulnar nerve in one patient, were performed in Group 1. No secondary procedures were performed in Group 2.
The long-term results of capitellocondylar total elbow replacement have been documented4. The major problems with an unconstrained total elbow-resurfacing arthroplasty such as the capitellocondylar design are postoperative dislocation or subluxation of the implant as well as dysfunction of the ulnar nerve4,16. The prerequisites for stability of the implant include sufficient bone to support the implant, integrity of the soft tissue, and proper operative technique4,11. It has been suggested that ligamentous instability alone in a patient who has rheumatoid arthritis is not a contraindication to elbow-resurfacing arthroplasty4. In the present study, the prevalence of instability associated with the total elbow arthroplasty was significantly increased (p < 0.009) in the patients who had had failure of an excision of the radial head and synovectomy (Group 1). The soft-tissue envelope must be balanced to prevent dislocation or asymmetrical articulation of the prosthetic components4,11. If an excision of the radial head and synovectomy has been performed previously, the normal soft-tissue tension may be altered. The lateral aspect of the capsule and the lateral soft tissues may be shortened in relation to the medial structures, as there is nothing to prevent proximal migration of the radius. Moreover, scarring and adhesions in the medial gutter, which is just inside of the ulnar collateral ligament, may effectively shorten the medial collateral ligament. This imbalance of soft-tissue tension, which was seen in Group 1, may lead to intraoperative difficulties with subsequent subluxation or dislocation of the elbow. Late instability of the elbow components in Group 1 may have been due to the failure to divide adhesions near the medial collateral ligament. In such instances, adhesions may confer the false impression that the implant has medial stability. However, with time, the adhesions stretch, causing medial laxity and instability. In addition, altered anatomy may prevent determination of the correct center of rotation of the ulnar and humeral components and the correct axial alignment. Use of an unconstrained prosthesis necessitates greater attention to the operative technique, including insertion of the components and repair of the soft tissues. The ulnar component should be in neutral rotation4. The humeral component should be externally rotated 5 degrees with respect to a line between the epicondyles4. The bone stock must be assessed to determine if it is adequate. Extensive loss of the capitellum, trochlea, and trochlear notch of the ulna prevents the prosthesis from being seated properly4. If the bone stock is adequate, ligamentous stability can be achieved by meticulous repair of soft tissue and placement of the soft tissue under tension by restoration of its length with prosthetic components of the appropriate size4. The medial gutter must be cleared of adhesions to restore the normal length of the medial collateral ligament and the medial part of the capsule. If the bone stock is inadequate, so that the prosthesis cannot be seated properly, the use of a more constrained prosthesis may be indicated. Anterior capsulotomy should not be done in an attempt to correct a flexion contracture fully, as this can increase instability4. A trial reduction should be performed to assess stability. The components should track smoothly with no tendency to dislocate and with no more than one to two millimeters of distraction with the joint at 90 degrees and the forearm in full pronation4. An intraoperative radiograph made with the trial components in position may help to verify the correct position of the prosthetic components. When a total elbow-resurfacing arthroplasty is performed in a patient who has had an excision of the radial head and synovectomy, the posterior approach should be used cautiously, as instability of the elbow components was seen in two of our four patients in whom this exposure had been used. Instability after use of the posterior approach may be related to an increased chance of injury of the medial ligament, given the increased exposure necessary and the close proximity of the ligament during the initial dissection. The posterior approach also necessitates a difficult repair of the medial aspect of the capsule, which is not necessary with the lateral approach. The design of the implant is an important consideration. A semiconstrained prosthesis should be available when an arthroplasty is being performed in a patient who has had an excision of the radial head and synovectomy. If the bone stock is inadequate or the trial prosthetic components are not stable with the joint in 90 degrees of flexion and the forearm in full pronation and if the components have a tendency to dislocate after adequate balancing, a more constrained prosthesis may be necessary. Such a prosthesis can tolerate more soft-tissue laxity and loss of metaphyseal bone stock5. The increased constraint may be necessary to provide adequate stability of the elbow replacement. Maloney and Schurman reported that postoperative dislocation of an unconstrained surface-replacement elbow prosthesis can be prevented with immobilization of the elbow in a plaster splint immediately after the operation. In their study, the patients wore an above-the-elbow splint for four weeks. After immobilization, a satisfactory range of motion was achieved without physical therapy9. In our series, early range-of-motion exercises, including flexion-extension and rotation of the forearm, were started on the third postoperative day. Therefore, it may be prudent to increase the duration of postoperative immobilization after implantation of a capitellocondylar prosthesis in a patient who has had previous excision of the radial head and synovectomy, particularly if instability was found intraoperatively. This may be especially important if it was possible to distract the components more than two or three millimeters at the time of the operation. Because the result of elbow replacement may be less durable in a patient who has had an excision of the radial head and synovectomy, primary arthroplasty should be considered for elderly patients who make low demands on the elbow. For younger patients, in whom a more biological procedure is indicated, careful attention should be directed to the medial and lateral ligaments and to the capsule in order to ensure that they are maintained for future reconstruction of the elbow. For these patients, we cannot recommend the abandonment of excision of the radial head and synovectomy as a primary procedure, as the average time between this procedure and the arthroplasty in our patients was six years and could be as long as eighteen years. In addition, we studied only patients who had had a failed excision of the radial head and synovectomy. In conclusion, although excision of the radial head and synovectomy is an effective method of treating a painful rheumatoid elbow, conversion to a capitellocondylar total elbow replacement may be difficult. The results of revision at a minimum of two years were inferior to those of primary capitellocondylar total elbow arthroplasty. If stability of the components cannot be accomplished at the time of the operative procedure, the use of a more constrained prosthesis should be considered.
*One or more of the authors has received or will receive benefits for personal or professional use from a commercial party related directly or indirectly to the subject of this article. In addition, benefits have been or will be directed to a research fund, foundation, educational institution, or other non-profit organization with which one or more of the authors is associated. No funds were received in support of this study.
  CiteULike  Connotea  Del.icio.us  Facebook  Technorati  Twitter What's this?
This article has been cited by other articles:
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Top
Abstract
Introduction
| home | CME | help | feedback | subscriptions | archive | site index |
|
Stanford University Libraries' HighWire Press (TM) assists in the publication of JBJS Online. |