Micromotion of the Souter-Strathclyde total elbow prosthesis in patients with rheumatoid arthritis

21 elbows in 18 patients with rheumatoid arthritis were treated with a Souter-Strathclyde total elbow prosthesis. 18 elbows were included in a radiostereometry (RSA) study. The aim of this clinical RSA study was to assess the three-dimensional micromotion pattern of the Souter-Strathclyde prosthesis, and thereby gain insight in the aseptic loosening process of this prosthesis. Implants were defined as at risk of aseptic loosening when the translation rate during the second postoperative year was more than 0.4 mm along one or more coordinate axes and/or the rate of rotation was more than 1° about one or more coordinate axes. Clinical examination revealed an increase in the range of motion and a marked reduction in pain. The RSA showed that 8 of 18 humeral components were at risk of aseptic loosening, although no signs of such loosening - defined as a complete radiolucent line of 2 mm or more - were found on the plain radiographs. In 7 humeral components, an anterior tilt about the transverse axis was seen that resulted in an anterior translation of the proximal tip and a posterior translation of the component's trochlea. Long-term studies of the Souter-Strathclyde prosthesis, have shown that this rotation is a specific pattern of failure in some implants. None of the ulnar components was at risk for aseptic loosening. Improvements in fixation of the Souter-Strathclyde total elbow arthroplasty should focus on the humeral component. At present, the lateral flange of the implant is enlarged to improve rotational stability about the transverse and longitudinal axes. The effect of this change in design on micromotion of the Souter-Strathclyde total elbow prosthesis will be studied in a randomized RSA study comparing the new design to the existing one.     

Use of the Souter-Strathclyde total elbow prosthesis in patients who have rheumatoid arthritis

Thirty-three patients had thirty-four consecutive primary arthroplasties, with use of the Souter-Strathclyde cemented unconstrained prosthesis, for severe rheumatoid arthritis of the elbow. The minimum duration of follow-up for inclusion in the study was two years. Three patients died. Four arthroplasties were revised: three, because of irreducible dislocation immediately after the operation and one, because of loosening without infection. One prosthesis was removed because of a late deep infection. In most of the remaining twenty-five patients (twenty-six arthroplasties), who had an average duration of follow-up of four years (range, two to eight years), pain was markedly less or had resolved completely, and the function of the elbow was greatly improved.     

Late results of the Souter-Strathclyde total elbow prosthesis in rheumatoid arthritis 6/19 implants loose after 5 years

We performed total elbow replacement, using the Souter-Strathclyde prosthesis in 19 elbows of 18 patients with rheumatoid arthritis and followed the patients for 5 (1-11) years. Pain relief was achieved initially in all patients. The average range of flexion-extension was increased by 12° and pronation-supination by 40°. There were no infections. 1 patient sustained an intraoperative fracture of the medial epicondyle, 3 patients developed neuropathies and 1 patient had an immediate postoperative dislocation of the joint.

At follow-up, 6 prostheses had radiographic loosening, with sagittal tilting and migration of 4 humeral components. 2 patients had clinical symptoms of loosening.     

Total elbow replacement with the Souter-Strathclyde prosthesis in rheumatoid arthritis. Long-term follow-up

We assessed the long-term results of 58 Souter-Strathclyde total elbow replacements in 49 patients with rheumatoid arthritis. The mean length of follow-up was 9.5 years (0.7 to 16.7). The mean pre-operative Mayo Elbow Performance Score was 30 (15 to 80) and at final follow-up was 82 (60 to 95). A total of 13 elbows (22.4%) were revised, ten (17.2%) for aseptic loosening, one (1.7%) for instability, one (1.7%) for secondary loosening after fracture, and one elbow (1.7%) was removed because of deep infection. The Kaplan-Meier survival rate was 70% and 53% at ten and 16 years, respectively. Failure of the ulnar component was found to be the main problem in relation to the loosening. Anterior transposition of the ulnar nerve had no influence on ulnar nerve paresthaesiae in these patients.     

Souter-Strathclyde total elbow arthroplasty in rheumatoid arthritis: medium-term results

We present the outcome of 47 Souter-Strathclyde replacements of the elbow with a mean follow-up of 82 months (12 to 129). The clinical results were assessed using a condition-specific outcome measure. The mean total score (maximum 100) before the operation was 47.21 and improved to 79.92 (p < 0.001). The mean pain score (maximum 50) improved from 21.41 to 46.70 (p < 0.001) and the mean functional component of the score (maximum 30) from 11.19 to 18.65 (p < 0.001). There was negligible change in the score for the range of movement although a significant improvement in mean flexion from 124 degrees to 136 degrees was noted (p < 0.001).Revision surgery was required in four patients, for dislocation, wound dehiscence and early infection in one, late infection in two and aseptic loosening in one. The cumulative survival was 75% at nine years for all causes of failure and 97% at ten years for aseptic loosening alone. Our study demonstrates the value of the Souter-Strathclyde total elbow arthroplasty in providing relief from pain and functional improvement in rheumatoid patients.     

Souter-Strathclyde arthroplasty of the rheumatoid elbow. 23 cases followed for 3 years

Twenty-three elbows in 17 rheumatoid arthritis patients have undergone unconstrained Souter-Strathclyde elbow replacements since March 1984. One patient developed a deep-wound infection, and 4 others had a temporary ulnar nerve paresis. At follow-up 3 (0.5-6) years postoperatively, there was a moderate improvement in the arc of movements: 25 degrees in extension-flexion and 45 degrees in forearm rotation. Pain relief was achieved in 20 cases. Three elbows required revision, two following recurrent dislocation and the other after a humeral fracture and component loosening.     

Souter-Strathclyde arthroplasty of the rheumatoid elbow: 23 cases followed for 3 years

Twenty-three elbows in 17 rheumatoid arthritis patients have undergone unconstrained Souter-Strathclyde elbow replacements since March 1984. One patient developed a deep-wound infection, and 4 others had a temporary ulnar nerve paresis. At follow-up 3 (0.5-6) years postoperatively, there was a moderate improvement in the arc of movements: 25° in extension-flexion and 45° in forearm rotation. Pain relief was achieved in 20 cases. Three elbows required revision, two following recurrent dislocation and the other after a humeral fracture and component loosening.     

Results of the Souter-Strathclyde total elbow arthroplasty in patients with rheumatoid arthritis: A preliminary report

The results of 19 consecutive Souter-Strathclyde total elbow arthroplasties (Zimmer, London) in 17 patients with a mean follow-up time of 41 months are reported. Pain relief was achieved in all cases, with 13 elbows becoming entirely painfree. The mean range of flexion increased 24° and extension improved 8°, with upper limb function greatly improved. The complication rate was 32%, including three nerve palsies, of which two resolved completely, and three early postoperative dislocations. There were two cases of prosthetic loosening, one following revision surgery for a traumatic humeral fracture in the early postoperative period. The authors consider the overall functional results with the Souter-Strathclyde prosthesis to be satisfactory in this group of patients.     

The Souter-Strathclyde elbow replacement in rheumatoid arthritis. 13 patients followed for 5 (1-9) years.

13 Souter-Strathclyde unconstrained elbow prostheses for rheumatoid arthritis were followed for 5 (1-9) years. Pain relief was achieved in all the patients. Flexion-extension was increased by 22 degrees, and pronation/supination by 27 degrees. There were no infections. Three humeral components were radiographically loose, but no patient had any symptoms. One patient sustained a fracture of the distal humeral epicondyle, two patients developed neuropathies and one patient had a postoperative dislocation that needed treatment with an external Hoffman fixator.     

Revision total elbow replacement using the Souter-Strathclyde prosthesis

The Souter-Strathclyde prosthesis was used in 52 evisions of total elbow replacements (TERs) between August 1986 and May 1997. Of these, 50, carried out in 45 patients, were prospectively followed for a mean of 53 months (14 to 139). The procedure produced reliable relief of pain, and the range of movement was preserved. There was a considerable incidence of adverse events associated with revision (30%), and 12 further procedures have been required. Nonetheless, a revision is the preferred salvage procedure for failed primary arthroplasty in the absence of sepsis.     

Kinematics and laxity of the Souter-Strathclyde total elbow prosthesis

The motion pattern and laxity of 8 cadaveric elbows were recorded with a 3-dimensional electromagnetic tracking device before and after the Souter-Strathclyde total elbow prosthesis was implanted. The Souter-Strathclyde prosthesis replicates the valgus-varus motion pattern of the intact elbow but causes a significant internal rotation of the ulnar shaft of 8.9 degrees +/- 4.1 degrees (P < .0005) at 110 degrees of elbow flexion. One of the reasons for this unphysiological motion pattern is positioning of the humeral component in a mean of 5.4 degrees +/- 6.4 degrees of external rotation compared with the intact elbow (P = .05). This positioning is related to the design of this device. The Souter-Strathclyde elbow prosthesis has a mean maximum valgus-varus laxity of 6.5 degrees +/- 1.5 degrees compared with 4.3 degrees +/- 2.3 degrees for the intact elbow (P = .004). This implant is more constrained than previously tested devices, which may explain its relatively higher loosening rate.     

Outcome of revision surgery for failed primary Souter-Strathclyde total elbow prosthesis

Total elbow arthroplasty is used for the treatment of the painful, destroyed elbow joint. With the increase in elbow replacement surgery in recent years, the number of revision surgeries will also increase. At our center, 236 primary Souter-Strathclyde total elbow prostheses have been placed. Twenty-four of these have been revised and were followed up for a mean of 74 months (range, 12-165 months). The postoperative clinical outcome after revision surgery can approximate the outcome after primary elbow replacement. Unfortunately, 8 elbows needed to be re-revised, 7 elbow prostheses loosened, and we had 1 early dislocation during follow-up. Three of the eight re-revised elbows had a third revision. Two other patients had a resection arthroplasty because of deep infection after the first revision. After 5 years, 73.8% of the revised elbow prostheses were still in situ. The lack of other satisfactory treatment options, combined with the satisfactory clinical results, justify revision surgery of elbow prostheses. The absence of intraoperative fracture during removal of the relatively small standard components and the availability of long-stemmed revision components, which facilitate fixation in the impaired bone, both support our preference for the Souter-Strathclyde prosthesis.     

The Kudo elbow prosthesis in rheumatoid arthritis: a consecutive series of 26 elbow replacements in 24 patients followed prospectively for a mean of 5 years

The Kudo prosthesis is the most commonly used elbow implant in Sweden. However, there are few reports of the results, besides those reported by Kudo himself. I have implanted 30 Kudo type 4 or 5 elbow prostheses in 28 patients with rheumatoid arthritis. 3 arthroplastics were revised, 2 because of loosening and 1 because of a periprosthetic ulnar fracture. 6 major peroperative or early postoperative complications occurred, but only 1 of these was a failure. 2 patients developed postoperative ulnar neuropathy, one was transient and the other patient died 1 year after surgery. 26 elbows were available for follow-up at an average 5 (2-8) years after implantation. All 26 functioned well although radiographic loosening of the humeral component was found in 1 patient. The average range of flexion increased by 14 degrees while the extension lag was unchanged (35 degrees). Activities of daily living had improved markedly and all but 3 patients were satisfied with their elbow. Radiolucent lines were seen around the proximal part of the ulnar component in 18/26 elbows. Although progressive in 1 patient only, this is a matter of concern, indicating that this component may be the weak part of the Kudo prosthesis.     

The Kudo total elbow arthroplasty in patients with rheumatoid arthritis

A Kudo total elbow arthroplasty (TEA) was performed in 36 elbows in 35 patients with rheumatoid arthritis. Of those 35, 4 died, 6 prostheses were revised, and 2 were lost to follow-up. Twenty-four elbows with a mean follow-up of 58 months were radiologically and clinically reviewed. Sixteen were scored as excellent by use of the Mayo score and Hospital for Special Surgery 2 score. The mean increase in active motion was 25 degrees. Two humeral and four ulnar radiologic loosenings were noted. Two early dislocations were successfully treated with closed reduction and cast immobilization, two patients used an elbow brace after the closed reduction, and one patient underwent a resection arthroplasty for instability and deep wound infection. Four aseptic loosenings, of which three had an intraoperative fracture at the index operation and one had instability, were revised. Despite initially excellent results, longer follow-up of TEA in rheumatoid patients demonstrated deterioration of the outcome and increased loosening.     

The Kudo elbow prosthesis in rheumatoid arthritis

The Kudo prosthesis is the most commonly used elbow implant in Sweden. However, there are few reports of the results, besides those reported by Kudo himself. I have implanted 30 Kudo type 4 or 5 elbow prostheses in 28 patients with rheumatoid arthritis. 3 arthroplastics were revised, 2 because of loosening and 1 because of a periprosthetic ulnar fracture. 6 major peroperative or early postoperative complications occurred, but only 1 of these was a failure. 2 patients developed postoperative ulnar neuropathy, one was transient and the other patient died 1 year after surgery. 26 elbows were available for follow-up at an average 5 (2-8) years after implantation. All 26 functioned well although radiographic loosening of the humeral component was found in 1 patient. The average range of flexion increased by 14 degrees while the extension lag was unchanged (35 degrees). Activities of daily living had improved markedly and all but 3 patients were satisfied with their elbow. Radiolucent lines were seen around the proximal part of the ulnar component in 18/26 elbows. Although progressive in 1 patient only, this is a matter of concern, indicating that this component may be the weak part of the Kudo prosthesis.     

Total elbow arthroplasty in rheumatoid arthritis: 20 GSBIII prostheses followed 2-5 years

From 1993 to 1996, we implanted 20 primary GSB III prostheses in 17 patients with rheumatoid arthritis. The Mayo Clinic performance index for the elbow was used for the evaluation. The average follow-up was 3 (2-5) years. At the follow-up examination, 12 elbows had an excellent result and 8 a good result. The median performance index increased from 30 (15-53) points to 95 (80-100) points. The subjective assessment was excellent for 11 elbows, good for 8 and poor for 1. 2 elbows had radiographic loosening with a progressive radiolucent line and a change in the orientation of the prosthesis.     

Total elbow arthroplasty in rheumatoid arthritis: 20 GSBIII prostheses followed 2–5 years

From 1993 to 1996, we implanted 20 primary GSB III prostheses in 17 patients with rheumatoid arthritis. The Mayo Clinic performance index for the elbow was used for the evaluation. The average follow-up was 3 (2–5) years. At the follow-up examination, 12 elbows had an excellent result and 8 a good result. The median performance index increased from 30 (15–53) points to 95 (80–100) points. The subjective assessment was excellent for 11 elbows, good for 8 and poor for 1. 2 elbows had radiographic loosening with a progressive radiolucent line and a change in the orientation of the prosthesis.