FOLLOW-UP OF THE MACINTOSH ARTHROPLASTY OF THE KNEE JOINT*

Transcription

1 Rheum, phys. Med., 1972,11, 217 ORIGINAL PAPER FOLLOW-UP OF THE MACINTOSH ARTHROPLASTY OF THE KNEE JOINT* BY J. D. JESSOPt AND C. J. MOOREt SUMMARY The results of arthroplasty of the knee joint in 2 patients with rheumatoid arthritis using the Macintosh prosthesis have been reviewed. Twenty-eight operations were performed in patients with severe disabling pain in the knee, well-marked radiological changes, and usually with flexion and valgus deformities. By our criteria only 2% achieved a good result after an average follow-up of three years. Possible reasons for this poor success rate are discussed. In the absence of a satisfactory total knee replacement so far, this arthroplasty may be considered as an alternative to arthrodesis in certain patients with rheumatoid arthritis. Our data indicate that those with multiple joint involvement, severe disabling pain in the knees with flexion and valgus deformities not greater than 30 degrees have a 50% chance of a good result. THE surgical treatment of a knee joint which is severely affected by rheumatoid arthritis remains unsatisfactory. The principle of an interposition arthroplasty, when material is interposed between bone ends to prevent them from becoming adherent, was first suggested by Verneuil (1860). Many reports have subsequently appeared in the literature of the results of interposition arthroplasties using a variety of materials; these include chromicized pig's bladder (Baer, 1918); fascia lata (Putti, 1920; Samson, 199; Speed and Trout, 199); vitallium (Campbell, 190); cellophane (McKeever, 193); nylon (Kuhns et al., 1950), and skin (Brown, McGaw, and Shaw, 1958). In most of these series patients had knee joints severely damaged by conditions other than rheumatoid arthritis. In 1969 Platt and Pepler described their own stainless steel mould to cover the femoral condyles and reported encouraging results in a ten-year follow-up which included 5 operations on patients with rheumatoid arthritis. In 1950 McKeever described a prosthesis to be placed on the tibial condyles, and this prosthesis was later modified by Macintosh. In 1965 Macintosh performed this operation at The London Hospital on two patients with rheumatoid arthritis. This paper presents the results of the operations performed between 1965 and 1967 at The London Hospital and at Notley Hospital, Braintree, Essex. MATERIALS AND METHODS Between 1965 and 1967 this operation was performed on 33 patients with classical or definite rheumatoid arthritis (Ropes et al., 1959). All patients suffered from progressive rheumatoid arthritis and severe disabling pain in the knee, often Based on a paper read at the Annual Meeting of the British Association of Physical Medicine and Rheumatology, London, March t Present appointment: Consultant in Physical Medicine and Rheumatology, University Hospital of Wales, Cardiff. % Consultant Orthopaedic Surgeon, Chelmsford and St. Helena Group Hospitals. 217

2 218 RHEUMATOLOGY AND PHYSICAL MEDICINE VOL. XI NO. 5 associated with flexion and valgus deformities and always with well-marked radiological changes. At follow-up three patients were found to have died from unrelated causes and six patients were unable to attend. Of the 2 patients reviewed four had arthroplasties on both knees, leaving a total of 28 operations to be analysed. The mean age at the time of operation was 58 years (38-78 years). The mean duration of the disease process was 15 years (3-32 years), while the mean duration in the knees was 9 years (1-26 years). Eight patients were receiving corticosteroid therapy at the time of operation. Follow-up assessments were carried out at a combined clinic. The patients were questioned regarding pain relief following the operation, and the severity of the pain was graded on a 0- scale (0 = no pain; = severe disabling pain). The knee joints which had undergone arthroplasty were examined for the presence of deformity, instability, passive range of movement, and extensor lag, Radiographs were taken in the antero-posterior position in extension and lateral position with the knee flexed as close to 90 degrees as possible. Finally the patient's own assessment of the operation was recorded. OPERATION DETAILS Twenty-eight operations were performed. In ten knees one tibial plateau was replaced (hemi-arthroplasty) and in the remainder both plateaux were replaced (double hemi-arthroplasty). In three patients a synovectomy was also performed, and in one case a synovectomy had been performed two years previously. One patient had a patellectomy. OPERATIVE TECHNIQUE The operation is performed under general anaesthesia using a tourniquet. The patient lies supine with the knee flexed to 90 degrees. Parapatellar incisions, medial and/or lateral, are usually adequate for moderate deformities, but in severely disorganized joints the patellar tendon insertion is raised with a block of attached bone. Following adequate exposure, beds are cut for the prostheses in the upper surface of the tibial condyles. These must be flat and are best cut with a Stryker saw, removing only the minimum of bone. The intercondylar area is resected if necessary together with any ridges on the femoral condyles. Tissues must be released to give enough relaxation to allow gliding of the tibia on the femoral condyles during flexion and extension of the knee. Simultaneous patellectomy is avoided when possible. The prostheses are carefully placed flat on their prepared beds. The approximate size and thickness of prosthesis is selected to restore alignment and to take up slack in the collateral ligaments. Soon they become embedded in scar tissue and the serrated lower surface helps to maintain the prostheses in position. If the patellar tendon has been detached it is firmly wedged back with its bone block. A drain is inserted and the incision closed in layers. A light compression bandage is applied with a plaster-of-paris back splint.

3 JESSOP AND MOORE: ARTHROPLASTY OF KNEE JOINT 219 POSTOPERATIVE MANAGEMENT Isometric quadriceps exercises are encouraged starting on the day after operation. The drain is removed after 2 hours, the back slab at five days, and the wound then inspected. If healing is satisfactory, early flexion and partial weight-bearing is allowed. When the patellar tendon has been detached, straight leg lifts are best avoided for a month. Throughout, emphasis is on movement rather than weight-bearing. All stages of advancement must be planned to avoid aggravation of pain. If after three weeks flexion remains less than 90 degrees, manipulation under anaesthesia may be required. In uncomplicated cases the average duration in hospital is three to four weeks, but postoperative exercises are usually necessary for three to six months after discharge. RESULTS The mean duration of follow-up was three years (10-52 months). The results have been classified as "good", "fair", or "poor" by the criteria shown in Table I. GOOD FAIR POOR Pain Flexion Deformity \ TABLE I CRITERIA FOR ASSESSMENT OF RESULTS One of the following: Pain Flexion _.,.. f Flexion Deformity ) Valgus/Varm All other cases Alleviated partially or completely >70 Unchanged <70 > 10 > 10 The results are shown in Table II. Out of 28 operations, only (2-8 %) had a good result. Result TABLE H RESULTS (28 OPERATIONS) Patient Assessment Doctor Per cent of Total Good There was a close agreement between the patients' over-all opinion of the result of the operation and the doctor's assessment as shown in Table II. Further analysis of the three groups of patients showed that the duration of follow-up in each group was almost the same (Table III). Of the patients with a poor result,

4 220 RHEUMATOLOGY AND PHYSICAL MEDICINE VOL. XI NO. 5 six required revision, five being arthrodesed and one having a Shier's hinge prosthesis inserted. The mean duration to revision was 22 months (10-8 months). TABLE III DURATION OF FOLLOW-UP Results No. of Operations Follow-up (months) All patients Good (Still Macintosh) (Revised) A critical factor in the assessment was pain relief, and significant alleviation of pain was achieved in 57 % of all operations. Only two out of twelve operations (17%) in the group classified as "poor" at follow-up resulted in significant pain relief (Table TV). Results All patients Good TABLE IV PAIN RELIEF Operations 28 Pain Relief Per cent The preoperative deformity was obtained in most cases from the patients' records and is shown in Tables V and VI. The preoperative flexion deformity was comparable in the three groups of patients (Table V), but those who finally had a poor result tended to have more severe preoperative valgus deformity than those in the other groups (Table VI). TABLE V PREOPERATIVE FLEXION DEFORMITY Results.? Flexion Deformity Operations All patients (0-35 ) Good (0-30 ) (0-30 ) (0-35 )

5 JESSOP AND MOORE: ARTHROPLASTY OF KNEE JOINT 221 Results All patients Good.. TABLE VI PREOPERATIVE VALGUS/VARUS No. of Operations DEFORMITY Valgus/Varus Deformity 11 (0-30 ) 9 (0-20 ) 9 (0-25 ) 1 (0-30 ) The mean range of flexion before and after operation is shown in Table VII. Most knees had a good range of movement before operation and the majority gained in range as a result of the operation. Although six patients gained movement in the group classified as "poor", it was not a major factor in assessment, presumably because of an already acceptable degree of mobility. Results All patients.. Good Gain Loss 7 1 TABLE VH RANGE OF FLEXION No Change 1 1 No. of Operations Degrees Preoperative of Flexion Postoperative It might be expected that if only one tibial plateau has been destroyed a hemiarthroplasty could produce better results than are obtained in more severely involved knees requiring a double hemi-arthroplasty. In our series ten patients had a hemi-arthroplasty, but only four had a good result (0%), while eight out of 18 double hemi-arthroplasties (%) had a good result. The results of this operation on the same group of patients were reviewed in 1968, when the mean duration of follow-up was 16 months (Table VIII). Analyses of these data suggest that if patients are to achieve a good result it must be within the first postoperative year, otherwise they are unlikely to improve, and in fact TABLE VEI COMPARISON OF RESULTS, 1968 AND 1970 Results Good Total number of operations Mean duration of follow-up (months)

6 222 RHEUMATOLOGY AND PHYSICAL MEDICINE VOL. XI NO. 5 will probably deteriorate. A longer period of observation is required to see how long patients remain in the group classified as "good". COMPLICATIONS The over-all incidence of complications was 6-%, and most of the patients with a "poor" result had developed some postoperative complication. These complications have been listed as "early" and "late" and are shown in Table IX. Patellar tendon divided 1 Patellar tendon ruptured 3 TABLE DC COMPLICATIONS EARLY (Operation < 6 weeks) Fractured tibia (M.U.A. at 6/52) 1 Wound infection Deep vein thrombosis Joint infection at 7 months 1 1 Joint infection at 3 years LATE (> 6 weeks) 1 J Flattening of femoral condyles The commonest complication was wound infection, which usually cleared up with the use of antibiotics, but in one case led directly to septic arthritis due to Staphylococcus aureus. A second patient developed a septic arthritis, Staphylococcus aureus being cultured from the joint, but with no apparent septic focus, three years after insertion of the prosthesis. Some degree of collapse of the femoral condyles may accompany this operation, presumably due to the soft bone of the femoral condyles wearing against the metal plates on the tibia. Plate XTV, Figs, la-c demonstrate this in its most extreme form, and in five other radiographs this was noted to a much milder degree. Plate XIV, Figs, la-c collapse of an erosion in the lateral femoral condyle which occurred 18 months after the operation and led directly to a bad result. 2 DISCUSSION The problem of arthroplasty of the knee joint has recently been reviewed by Taylor (1971), who stresses the need for assessment of the results of the more recently developed arthroplasties. So far few reports have appeared in the literature recording results of the Macintosh arthroplasty. In 1965 Macintosh

7 PLATE XIV FIG. la FIG. \b FIG. la. Preoperative radiograph. Lateral view of knee joint in flexion affected by rheumatoid arthritis for 11 years. Contour of femoral condyles appears well preserved. FIG. Ib. Postoperative radiograph. Lateral view of same knee joint two years after insertion of Macintosh prostheses, showing well-marked flattening of femoral condyle. FIG. If. Gross destruction of femoral condyle three years after arthroplasty. FIG. lc

8 PLATE XIV continued FIG. la FIG. 2a. Preoperative radiograph. Anteroposterior view of knee joint severely affected by rheumatoid arthritis, especially in lateral tibio-femoral compartment. FIG. 2b. Postoperative radiograph taken one year after insertion of Macintosh prostheses. showing prostheses maintained in good position. FIG. 2C. Radiograph taken 18 months after arthroplasty. showing collapse of eroded lateral femoral condyle. FIG. 2b FIG. 2C

9 JESSOP AND MOORE: ARTHROPLASTY OF KNEE JOINT 223 analysed his own results of the operation on patients with rheumatoid arthritis followed for an average of 2\ years and claimed 72% had a good result. Potter (1969) reported from the United States on 95 patients with rheumatoid arthritis, and found 56% with a good result in a three-year follow-up using either the McKeever or the Macintosh prosthesis. Lowe, Kates, and Kay (1971) have achieved 63% good results from this operation in 83 knee joints affected by rheumatoid arthritis. Potter (1969) suggested that contraindications should include valgus or flexion deformities greater than 30 degrees, large bone cysts in the femoral condyles, and severe impaction of the tibial plateaux. Lowe et al. (1971) also found this operation unsuitable in severe disease, and our own experiences support these contraindications. Lowe et al. claim substantially better results when the prostheses are fixed with methyl methacrylate filler to prevent slipping in certain cases. However, methyl methacrylate was not used for fixation of the prostheses in our series of patients. Our own small proportion of "good" results may be due to differences in selection of cases and methods of assessment, and in particular because eleven different surgeons performed these operations. Nevertheless the somewhat unsatisfactory results of partial replacement of the knee that is, replacement of the tibial plateaux are comparable to the uncertain results of partial replacement of the hip. At this hospital total replacement of this joint in rheumatoid arthritis has given such satisfactory results that partial replacement has been largely abandoned (Harris, Lightowler, and Todd, in preparation). At the knee, however, total replacement with devices having the form of a hinge has not found general acceptance. It is to be hoped that one of the prostheses now being developed with a different geometry will prove to be more successful. ACKNOWLEDGMENTS We are grateful to Mr. M. A. R. Freeman, Dr. Michael Mason, and Dr. C. G. Barnes for advice in the preparation of this paper and for allowing us to study patients under their care. We are also grateful to Sir Henry Osmond-Clarke, Mr. W. A. Law, Mr. O. J. Vaughan- Jackson, Mr. D. Dunn, and Mr. A. Hume for permitting us to report on the results of the operations which they performed, and to Miss Olive Sporton for secretarial assistance. REFERENCES BAER, W. S. (1918) "Arthroplasty with the Aid of Animal Membrane". Amer. J. orthop. Surg., 16, 1. BROWN, J. E., MOGAW, W. H., and SHAW, D. T. (1958) "Use of Cutis as an Interposing 'Membrane in Arthroplasty of the Knee". /. Bone Jt Surg., 0A, CAMPBELL, W. C. (190) "Interposition of Vitallium Plates in Arthroplasties of the Knee". Amer.]. Surg., 7, 639. HARRIS, J., LIGHTOWLER, C. D. R., and TODD, R. C. In preparation. KUHNS, J. G., POTTER, T. A., HORNELL, R. S., and ELLISTON, W. A. (1953) "Nylon Membrane Arthroplasty of the Knee in Chronic Arthritis". J. Bone Jt Surg., 35A, 929. LOWE, L. W., KATES, A., and KAY, A. G. L. (1971) "Macintosh Arthroplasty in the Rheumatoid Knee". Paper read at the British Orthopaedic Association Meeting, Oxford, September 1971.

10 22 RHEUMATOLOGY AND PHYSICAL MEDICINE VOL. XI NO. 5 MACINTOSH, D. L. (1958) "Hemiarthroplasty of the Knee using a Space-occupying Prosthesis for Painful Valgus and Varus Deformities". J. Bone Jt Surg., 0A, 131. (1965) "Arthroplasty of the Knee in Rheumatoid Arthritis using the 'Hemiarthroplasty' Prosthesis". Paper read at the British Orthopaedic Association Meeting, Autumn MCKEEVER, D. C. (193) "The Use of Cellophane as an Interposition Membrane in Synovectomy". /. Bone Jt Surg., 1, 576. (1960) "Tibial Plateau Prosthesis". Clin. Orthop., 18, 86. PLATT, G., and PEPLER, C. (1969) "Mould Arthroplasty of the Knee". J. Bone Jt Surg., 51B, 76. POTTER, T. A. (1969) "Arthroplasty of the Knee with Tibial MetaBic Implants of the McKeever and Macintosh Design". Surg. Clin. N. Amer., 9,903. Purn, V. (1920) "Arthroplasty of the Knee Joint". J. orthop. Surg., n.s. 2, 530. ROPES, M. W., BENNETT, G. A., COBB, S., JACOX, R., and JESSAR, R. A. (1959) "Diagnostic Criteria for Rheumatoid Arthritis: 1958 Revision". Ann. rheum. Dis., 18,9. SAMSON, J. E. (199) "Arthroplasty of the Knee: Late Results". J. Bone Jt Surg., 31B, 50. SPEED, J. S., and TROUT, P. C. (199) "Arthroplasty of the Knee: a Follow-up Study". /. BoneJt Surg., 31B, 53. TAYLOR, A. R. (1971) In Modern Trends in Rheumatology, vol. II, ed. A. G. S. Hill. Butterworth, London, p VERNEUIL, A. S. (1860) Arch. gin. Mid., 15,17.