Abstract
Background: There is a paucity of reports regarding the long-term
results of total knee arthroplasty in patients with juvenile rheumatoid
arthritis. The purpose of this study was to evaluate the outcome of total knee
arthroplasty in patients with juvenile rheumatoid arthritis who had been
followed for a minimum of twelve years.
Methods: Eight consecutive patients (fifteen knees) with juvenile
rheumatoid arthritis underwent total knee arthroplasty at an average age of
16.8 years. Clinical evaluation of pain status, range of motion, and the
ability to walk and radiographic evaluation of the alignment of the knees and
component loosening were performed preoperatively and at a mean of 15.5 years
postoperatively.
Results: All patients had substantial pain and functional limitation
before the surgery, and seven of the eight patients used a wheelchair. At the
time of the latest follow-up, which was after revision surgery in three
patients, all of the knees were pain-free and six patients were able to walk
about the community. The mean arc of motion had increased from 36° to
79°. The final radiographic evaluation showed that thirteen of the fifteen
knees were in neutral alignment and two were in valgus. Failure, defined as
revision of any of the components or definite loosening as seen
radiographically, occurred in three knees.
Conclusions: Good results, in terms of pain relief and restoration
of function, were seen at a minimum of twelve years following total knee
arthroplasty in our series of patients with juvenile rheumatoid arthritis.
This procedure is a reasonable option when nonoperative therapy has been
inadequate for patients with severe disability and pain in this relatively
young population.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.
Juvenile rheumatoid arthritis is a debilitating disease that affects
patients sixteen years old and
younger1. The
typical age of onset is bimodal, with a peak onset at eight years of age and a
later peak during puberty. A review of the literature showed that 17% to 50%
of patients eventually have severe, life-altering
disease2.
While the effectiveness of total knee arthroplasty for elderly patients is
well established, the literature contains limited information on the role of
this procedure in very young patients and we are not aware of any long-term
studies of the outcome of total knee arthroplasty in patients with juvenile
rheumatoid arthritis. The aim of the present study was to determine the
long-term clinical and radiographic results and implant survival following
total knee arthroplasty in patients with juvenile rheumatoid arthritis.
A review of the patient database of the senior author (D.H.P.)
revealed that, from 1986 to 1990, eight consecutive patients with juvenile
rheumatoid arthritis had undergone a total of fifteen primary total knee
arthroplasties. After our internal review board granted approval, two of the
investigators, who were not associated with the initial surgery, collected
data by reviewing the patients' medical records and radiographs as well as
through telephone interviews. All eight patients were available for follow-up
and were included in the analysis until the time of death or revision.
Surgical Technique
Preoperative flexion contractures of <10° were treated with passive
stretching and the application of a night splint. A custom-made
extensor-anterior translation knee brace was used for flexion contractures of
between 10° and 50°, and skeletal traction was employed for
contractures of >50°.
All of the knees were approached through a median parapatellar incision.
After adequate soft-tissue releases and exposure, a
posterior-cruciate-retaining Miller-Galante prosthesis (Zimmer, Warsaw,
Indiana) was implanted without cement. One patient required custom-made
components (Tech-Medica, Minneapolis, Minnesota) because of the small size of
the distal part of the femur and the proximal part of the tibia. A
metal-backed uncemented patellar component was used in all patients.
Supplementary screw fixation was used for all of the fifteen tibial
components. In twelve cases, the bone quality was documented to be poor and
cement was applied to the holes prior to screw placement to aid the component
fixation. No cement was placed on the undersurface of the tibial component,
and none was used in the fixation of the femoral implants.
Associated procedures performed during the total knee arthroplasties
included autologous bone-grafting of focal deficiencies in the femur or tibia,
or both, in eight limbs in four patients. The average blood loss was 500 mL
(range, 200 to 1200 mL).
Continuous passive range-of-motion exercises were started postoperatively.
The patients were allowed to bear full weight as tolerated on the second
postoperative day. On the third postoperative day, they began walking as
tolerated.
Functional Assessment
The level of pain was documented before the surgery and at the time of the
latest follow-up. Data on preoperative functional and ambulatory status were
extracted from the charts. Ambulatory status and social level of functioning
were determined at the time of the latest follow-up. All of the patients were
seen at our pediatric hospital until they reached the age of twenty-one, at
which point they started being followed at an outside institution. All
patients being followed at an outside institution were contacted by telephone
to determine their functional and pain status.
Radiographic Assessment
Standing anteroposterior and lateral radiographs were assessed for
alignment preoperatively and at the time of the latest follow-up. Radiographs
were also examined for evidence of radiolucency at the bone-implant interface
of all of the components. Loosening was defined radiographically as the
presence of a radiolucent line of >2 mm in thickness around the entire
circumference of the prosthesis, subsidence of the component, or a change in
alignment in comparison with that seen on a previous radiograph.
The demographic characteristics of each patient are outlined in the
Appendix. All of the patients were female, and their mean age was 16.8 years
(range, fourteen to twenty years) at the time of surgery. The mean interval
between the onset of the disease and the surgery was 13.5 years (range, six to
18.5 years). Eight right knees and seven left knees were involved. The
patients had a mean height of 147.6 cm (range, 116 to 168 cm) and an average
weight of 48.1 kg (range, 27 to 71 kg). All of the patients had persistent
pain and disability that had been refractory to conservative management. All
were severely disabled with end-stage polyarticular disease
(Charnley3 class C).
As a result, most had undergone, or underwent a short time after the total
knee arthroplasty, additional procedures on other joints (see Appendix). The
average duration of follow-up was 15.5 years (range, twelve to nineteen
years).
All of the patients were treated according to the surgical protocol that we
described. Seven patients underwent bilateral total knee arthroplasty under
the same anesthetic. It was necessary to mobilize soft tissues, which were
frequently adherent to the femoral condyles, in all of the patients. The
specific soft-tissue releases performed on each of the patients are summarized
in Table I.
Pain
All of the patients had severe pain in the involved knees prior to the
surgery. Twelve of the fifteen knees were pain-free at the time of the latest
follow-up. Three knees in two patients required revision procedures, at
fifteen and seventeen years. One of these patients, who had been treated with
bilateral total knee arthroplasty, had pain in both knees in association with
tibial loosening and polyethylene wear. The other patient had pain stemming
from a loose patellar component. These three knees were pain-free following
the revision surgery.
Functional Status
All patients had functional improvement at the time of the latest
follow-up. Preoperatively, seven of the eight patients were
wheelchair-dependent and one was capable of walking one block without
assistance. At the time of the latest follow-up, five of the eight patients
were capable of unlimited walking about the community, one was capable of
limited walking about the community, and two patients could walk about the
house but required use of a wheelchair when going places outside the home.
Social Function
Seven of the eight patients were employed full-time, and one was working
part-time. Four patients had married, and three patients had children. All of
the patients were able to function independently.
Range of Motion
There was a substantial improvement in the range of motion of the knees
after the total knee arthroplasties. The mean flexion-extension arc increased
from 36° preoperatively to 79° at the time of the latest follow-up.
Preoperatively, fourteen knees had a flexion contracture (range, 20° to
80°), and the average contracture for the series was 43.6°.
Postoperatively, only four knees had a flexion contracture (range, 15° to
30°), and the average contracture for the series was 6°.
Complications
An intraoperative fracture occurred in two patients. In one of them, a
compression fracture of the femoral trochlea occurred during insertion of a
custom-made femoral component. The patient was treated with a knee-immobilizer
for four weeks postoperatively, after which continuous passive range-of-motion
exercises were started. The fracture healed uneventfully. The other patient
had a supracondylar fracture resulting from a large cyst. The patient was
treated with a cast-brace for three weeks, and the fracture healed.
One patient had posterolateral instability of the knee resulting from an
excessive release of the arcuate complex. This was treated successfully with
cast-bracing. Another patient sustained a proximal tibial fracture during a
manipulation that was done to improve the range of motion six weeks after the
total knee arthroplasty. The fracture healed uneventfully after cast-bracing.
Still another patient had a transient peroneal nerve palsy following a
concomitant hamstring lengthening to improve extension; it resolved after
forty-eight hours.
Radiographs and Revisions
Preoperatively, nine of the fifteen knees had valgus deformity and four had
varus angulation. Neutral alignment was achieved in thirteen of the fifteen
knees, and valgus angulation was restored in two knees (Figs.
1-A and
1-B).
As mentioned above, one patient who had radiographic evidence of patellar
component loosening with concomitant symptoms underwent a patellar revision at
seventeen years after the index procedure. Another patient had radiographic
evidence of bilateral excessive polyethylene wear and tibial implant loosening
necessitating revision at fifteen years. None of the remaining knees had
evidence of loosening or implant migration at the time of the latest
follow-up.
Patients with juvenile rheumatoid arthritis generally have a poor
overall prognosis in terms of pain and function. It has been estimated that
approximately 50% of patients with polyarticular and systemic juvenile
rheumatoid arthritis and 40% of those with pauciarticular juvenile rheumatoid
arthritis will eventually have active arthritis and 17% will require a walking
aid within ten years after the onset of the
disease1.
Soft-tissue releases and synovectomies are performed for joints in early
stages of the disease. Joint replacement is an excellent option once there is
evidence of advanced osseous
destruction1,4-10.
Although
studies11-13
have shown good outcomes of total knee arthroplasty in patients with
adult-onset rheumatoid arthritis, the patients in those investigations were
older than our subjects. It has been theorized that prostheses have a shorter
duration of survival in younger patients because of the higher physical
demands on the implant. In addition, younger patients with juvenile rheumatoid
arthritis tend to have more severe disease than do patients with adult-onset
disease. More severe involvement of soft tissues and bone loss present the
surgeon with substantial technical challenges. Our results indicate that total
knee arthroplasty may enhance function and increase the independence of
patients with juvenile rheumatoid arthritis who have persistent pain and
functional limitations, are emotionally stable and motivated, and have the
necessary family and social support. It is possible that the generally
decreased level of physical activity of these patients, due to involvement of
multiple joints, contributes to longevity of the implants.
In many of these patients, physeal closure, a prerequisite for total joint
replacement, is premature. It is important to aggressively treat flexion
contractures, as we did with a protocol that included the use of an
extensor-anterior translation knee brace. This brace served to lever the tibia
anteriorly, thereby correcting the associated posterior subluxation of the
tibia, as well as to stretch the posterior soft tissues. Bilateral skeletal
tibial traction with longitudinal, anterior tibial and posterior femoral
directed forces over a period of seven to ten days was effective in treating
severe contractures of >50°. In addition, several soft-tissue
procedures were implemented to correct deformities and balance the ligaments
at the time of the surgery. Because of the chronic synovitis in these
patients, soft-tissue releases played an important role in facilitating
exposure of the distal part of the femur and proximal part of the tibia and
allowing proper placement of the components. The releases also improved the
range of motion. Patients with severe flexion contracture also required more
extensive distal femoral resection, posterior cruciate release, posterior
capsular release, and hamstring tendon release intraoperatively. Valgus
deformities required extensive lateral capsular releases and concomitant
medial capsular imbrication and advancement. In two patients, lateral
retinacular releases were necessary to optimize patellar tracking.
Several members of this cohort were of small stature, and standard
components were often too large. Therefore, preoperative measurement and
templating were essential. To determine the appropriate sizes of the
components, we made radiographs (or even computed tomography scans with a
standard reference marker) with a radiopaque ruler at the midportion of the
involved bone in both the anteroposterior and the lateral plane preoperatively
(Fig. 1-A). Particular findings
included a relative increase in the medial-lateral dimension relative to the
anteroposterior dimension of both the femur and the tibia and overgrowth of
the medial femoral condyle in knees with a valgus deformity. The proximal part
of the tibia was frequently dysplastic with rapid tapering of the metaphysis,
which precluded the use of components with a stem. In addition, bone quality
was often poor as a result of inactivity and systemic steroid use. Erosive and
rheumatoid cysts were frequently seen. Most knees had a markedly osteoporotic
and fragile medial femoral condyle, which was often infiltrated by fibrofatty
elements. Intraoperatively, careful placement of retractors was necessary to
avoid creating compression fractures. Bone-grafting had to be performed in the
majority of the patients. While cement fixation would have been more suitable
given the poor bone quality, all of the patients in this series were treated
without cement because of their young age. Cementless implants present the
theoretical advantage of longer survival, with the proviso of obtaining good
stability at the time of implantation. In this series, screws provided the
initial fixation. The technique of injecting cement into the drilled holes
prior to screw placement proved useful for enhancing fixation in the
osteoporotic bone.
All of the patients had polyarticular disease, and most required bilateral
total hip arthroplasty as well as hip contracture releases prior to the
bilateral total knee replacements. We believe that addressing all of the
diseased joints is necessary to achieve meaningful improvements in
function.
Tables presenting the demographic characteristics of all patients and
listing additional procedures performed on the patients are available with the
electronic versions of this article, on our web site at
(go to
the article citation and click on "Supplementary Material") and on
our quarterly CD-ROM (call our subscription department, at 781-449-9780, to
order the CD-ROM). ?
In support of their research or preparation of this manuscript, one or more
of the authors received grants or outside funding from Smith and Nephew. None
of the authors received payments or other benefits or a commitment or
agreement to provide such benefits from a commercial entity. No commercial
entity paid or directed, or agreed to pay or direct, any benefits to any
research fund, foundation, educational institution, or other charitable or
nonprofit organization with which the authors are affiliated or
associated.
Cassidy JT. Juvenile rheumatoid
arthritis. In: Kelly WN, Harris ED, Ruddy S, Sledge CB, editors.
Textbook of rheumatology. Philadelphia: W.B. Saunders;
1981. p 1279-305.1279
1981
Sherry DD. What's new in the diagnosis
and treatment of juvenile rheumatoid arthritis. J Pediatr
Orthop.2000;20:
419-20.20419
2000
[PubMed][CrossRef]
Charnley J. Low friction
arthroplasty of the hip: theory and practice. New York: Springer;
1979. p 66-90.66
1979
Sarokhan AJ, Scott RD, Thomas WH, Sledge
CB, Ewald FC, Cloos DW. Total knee arthroplasty in juvenile rheumatoid
arthritis. J Bone Joint Surg Am.1983;65:
1071-80.651071
1983
[PubMed]
Cage DJ, Granberry WM, Tullos HS.
Long-term results of total arthroplasty in adolescents with debilitating
polyarthropathy. Clin Orthop Relat Res.1992;283:
156-62.283156
1992
[PubMed]
Scott RD, Sarokhan AJ, Dalziel R. Total
hip and total knee arthroplasty in juvenile rheumatoid arthritis. Clin
Orthop Relat Res.1984;182:
90-8.18290
1984
Carmichael E, Chaplin DM. Total knee
arthroplasty in juvenile rheumatoid arthritis. A seven-year follow-up study.
Clin Orthop Relat Res.1986;210:
192-200.210192
1986
[PubMed]
Stuart MJ, Rand JA. Total knee
arthroplasty in young adults who have rheumatoid arthritis. J Bone
Joint Surg Am.1988;70:
84-7.7084
1988
Ewald F, Christie MJ. Results of
cemented total knee replacement in young patients. Orthop
Trans.1987;11:
442.11442
1987
Boublik M, Tsahakis PJ, Scott RD.
Cementless total knee arthroplasty in juvenile onset rheumatoid arthritis.
Clin Orthop Relat Res.1993;286:
88-93.28688
1993
[PubMed]
Ito J, Koshino T, Okamoto R, Saito T.
15-year follow-up study of total knee arthroplasty in patients with rheumatoid
arthritis. J Arthroplasty.2003;18:
984-92.18984
2003
[PubMed][CrossRef]
Chmell MJ, Scott RD. Total knee
arthroplasty in patients with rheumatoid arthritis. An overview. Clin
Orthop Relat Res.1999;366:
54-60.36654
1999
[CrossRef]
Archibeck MJ, Berger RA, Barden RM,
Jacobs JJ, Sheinkop MB, Rosenberg AG, Galante JO. Posterior cruciate
ligament-retaining total knee arthroplasty in patients with rheumatoid
arthritis. J Bone Joint Surg Am.2001;83:
1231-6.831231
2001
[PubMed]