Patients
Between April 1984 and January 1996, arthroscopic synovectomy
was performed on twenty-nine elbows in twenty-seven patients who
satisfied the diagnostic criteria for rheumatoid arthritis described
in 1987 by the American Rheumatism Association12. Seven patients
(eight elbows) were not followed: one patient died, one was too
ill to travel, and five were lost to follow-up. Therefore, twenty-one
elbows in twenty patients (seventeen women and three men) were included
in this study. The patients were followed for a minimum of forty-two
months (mean, ninety-seven months; range, forty-two to 160 months)
after the operation. Eleven patients were followed for more than
ten years. The mean age was 51.2 years (range, nineteen to seventy-one
years). The mean duration of the rheumatoid arthritis before the
operation was 11.6 years (range, six to twenty-six years), and the
mean duration of elbow symptoms was 4.7 years (range, ten months
to thirteen years). The operation was performed on ten right elbows
and eleven left elbows. All patients were under the care of rheumatologists
and were receiving systemic anti-rheumatic medications, including
intra-articular steroids.
Before the arthroscopic synovectomy, all twenty patients had received
physiotherapy. Seventeen of the twenty were managed with one or
two disease-modifying anti-rheumatic drugs: seven took auranofin;
seven, sodium aurothiomalate; four, penicillamine; three, salazosulfapyridine;
three, methotrexate; and one, bucillamine. After the operation,
all seventeen patients continued to take the same disease-modifying
anti-rheumatic drugs, except for two in whom general inflammatory
control was poor after the operation. Both switched to a different
disease-modifying anti-rheumatic drug. Three of the twenty patients
were treated with steroids, and all twenty also took nonsteroidal
anti-inflammatory drugs, such as indomethacin. No attempt was made
to standardize the patients’ medical treatment before or
after the operation.
Our indications for performing arthroscopic synovectomy were
severe pain or swelling as a result of synovitis that was unresponsive
to conservative therapies, including disease-modifying anti-rheumatic
drugs and the avoidance of provocative activity. These symptoms
had to have been severe enough to have interfered with work, daily
activities, or sleep for at least six months.
Assessment
The Mayo elbow performance score, which is employed to evaluate
pain (maximum, 45 points), motion (20 points), stability (10 points),
and daily function (25 points), was used to assess elbow function13
before the operation, two years after the operation, and at the
final follow-up evaluation (i.e., the most recently performed examination).
On the basis of this system, the results were categorized as excellent
(90 to 100 points), good (75 to 89 points), fair (60 to 74 points),
or poor (<60 points). Adequate preoperative data allowing
the calculation of a preoperative score were available for all twenty-one
elbows.
The radiographic findings were graded, according to the method
described by Larsen et al.14, before the operation and at the final
follow-up evaluation. According to the preoperative Larsen grade,
all elbows were classified into one of three groups: Grades 1 and
2, Grade 3, and Grade 4. The results were then compared among the
groups. Additionally, the results for elbows in which clinically
apparent synovitis recurred were compared with those for elbows
in which no apparent synovitis was observed. Each assessment was
performed blindly by one of the authors who had not performed the
operation.
Operative Technique
The technique of arthroscopic synovectomy has been described
previously11,15,16. In brief,
after inducement of general or axillary block anesthesia, we place
the patient in the lateral position with the involved side uppermost.
The arm is supported with the forearm hanging free and the elbow
flexed 90°. We use a pneumatic tourniquet to exsanguinate the arm.
Twenty milliliters of sterile normal saline solution is injected
to distend the capsule. Four portals are used: the mid-lateral,
posterolateral, anterolateral, and anteromedial. The mid-lateral
portal, which is located in the center of a triangle formed by the
olecranon, the lateral epicondyle, and the radial head, is useful
as both a diagnostic and an operative portal for the posterior compartment,
including the olecranon, the olecranon fossa, the posterior aspect
of the capitellum, and the posterior aspect of the radial head.
The posterolateral portal is established in the sulcus of the joint
space posterior to the mid-lateral portal for insertion of instruments
such as probes, graspers, and shavers. The anterolateral portal
is established exactly in the sulcus, between the radial head and
the capitellum anteriorly. The anteromedial portal is established
with use of the switch-stick technique.
The arthroscope is passed, under direct vision, through the front
of the joint from the anterolateral portal to the point of desired
entry seen on the synovial tissue medially, and the skin is then
incised over the rod. Anterior joint structures, such as the trochlea,
the medial condyle, the capitellum, the radial head, and the coronoid
process, can be accessed through the anterolateral and anteromedial
portals (Fig. 1).
When the synovectomy is performed in the anterior area, care must
be taken to avoid damaging the median nerve and the brachial artery
because of the thin brachialis muscle, which is characteristic of
patients with rheumatoid arthritis.
We use a 4.0-mm, 30° arthroscope with an attached camera, light
source, and fluid source. Proliferative synovial tissue is excised
to the extent possible with the grasper and the shaver. Rotation
of the forearm is important to facilitate detection of residual
synovial tissue behind the radial neck. The amount of synovial tissue
that is excised is usually less than the amount that is excised
in an open synovectomy, primarily because an arthroscopic synovectomy
cannot be performed in all areas of the joint space, especially
the medial gutter. In this regard, our arthroscopic synovectomy
is a subtotal synovectomy. We do not perform a capsular release
in this arthroscopic procedure.
We do not apply a splint, and the patients begin active motion of
the elbow under physician supervision on the day after the operation.
Statistical Analysis
Statistical comparisons were performed with use of repeated-measures
analysis of variance and the Dunnett test for subsequent assessments,
the Mann-Whitney U test for comparing the results of elbows with
and without recurrent synovitis, and the Scheffé test for
comparisons among Larsen grades. A probability value of <0.05
was considered to indicate a significant difference.
The mean Mayo elbow performance score improved from 48.3 points
preoperatively to 77.5 points (an excellent result in two elbows,
a good result in thirteen, a fair result in six, and a poor result
in none) at two years after the operation (Table I). The score
was excellent or good for fifteen elbows (71%) at two years
after the operation. The mean score had decreased to 69.8 points
(an excellent result in two elbows, a good result in seven, a fair
result in seven, and a poor result in five) at the final follow-up
evaluation, with an excellent or good score maintained for nine
elbows (43%). The difference between the scores before
and after the operation was significant (p < 0.05).
The Mayo elbow performance scores in the three groups are summarized
in Table II.
The Larsen grade was 1 or 2 for seven elbows, 3 for ten, and 4 for
four. All of the Grade-1 and 2 elbows were rated as excellent or
good at two years after the operation, and five of the seven remained
so at the final follow-up evaluation. Seven of the ten Grade-3 elbows
were rated as excellent or good at two years after the operation,
but only three of the ten remained so at the final follow-up evaluation.
One of the four Grade-4 elbows was rated good at two years after
the operation and remained so at the final follow-up evaluation.
Pain
The scores for pain are summarized for the series as a whole in Table I and according
to the three groups in Table III. All of the Grade-1 and 2 elbows
were mildly or not painful at two years after the operation. Of
the ten Grade-3 elbows, all were mildly or not painful at two years
after the operation and seven were mildly or not painful at the
final follow-up evaluation. Of the four Grade-4 elbows, three were
mildly painful at two years after the operation and two were mildly
painful at the final follow-up evaluation.
Range of Motion
The ranges of motion are summarized in Table IV. No significant
increase in the range of motion was observed either at two years
after the operation or at the final follow-up evaluation in the
series as a whole or in any of the three groups.
Stability
The Mayo elbow performance scores for stability are summarized
in Table I.
Before the operation, eleven elbows (52%) were stable and ten
(48%) were moderately unstable. Two years after the operation,
eight elbows (38%) were stable and thirteen (62%) were
moderately unstable. At the final follow-up evaluation, five elbows
(24%) were stable, fourteen (67%) were moderately
unstable, and two (10%) were grossly unstable; all groups
showed a tendency for deterioration with regard to stability.
Daily Function
The scores for daily function are summarized in Table I . The mean
score increased significantly after the operation and then showed
a tendency to decrease. Significant improvement in the score persisted
at the final follow-up evaluation (p < 0.05), but only
four patients reported that the elbow did not interfere with any
of their daily living activities.
Radiographic Assessment
Standardized anteroposterior and lateral radiographs of all twenty-one
elbows were evaluated blindly by one of us according to the grading
system of Larsen et al.14 before
the operation and at the final follow-up evaluation. Degenerative
change increased by one grade in fourteen elbows, by two grades
in two elbows, and by three grades in one elbow. No degenerative
changes were observed in four elbows, three of which were followed
for nearly five years after the operation. Furthermore, of the eleven
elbows that were followed for more than ten years, seven had an
increase in the degenerative change by one grade, three had an increase by
more than two grades, and one (Grade-4) had no degenerative change.
None of these eleven elbows required total elbow arthroplasty.
Complications
Transitory ulnar nerve paresthesias developed in three elbows (one
Grade-1 or 2 elbow, one Grade-3 elbow, and one Grade-4 elbow). All
patients recovered completely, without specific treatment, within
three months. None of the elbows had a superficial or deep infection
or vascular injury.
Recurrence of Synovitis and Reoperations
Clinically apparent synovitis recurred in five of the twenty-one
elbows; one of the five elbows was Grade 1 or 2, two were Grade
3, and two were Grade 4. The mean period until recurrence was twenty-four
months after the operation. Both Grade-4 elbows gradually began
to be much more painful, and radiographic assessments showed progression
of joint destruction. Therefore, total elbow arthroplasty was performed
at forty-six months and fifty-four months in these two elbows.
The Mayo elbow performance score of the five elbows in which
clinically apparent synovitis recurred averaged 43.4 points before
the operation, 72.6 points at two years after the operation, and
54.4 points at the final follow-up evaluation. The Mayo elbow performance
score of the elbows in which no apparent synovitis was observed
averaged 49.8 points before the operation, 79.0 points at two years
after the operation, and 74.6 points at the final follow-up evaluation.
Only the Mayo elbow performance scores at the final follow-up evaluation
differed significantly (p < 0.05) between these two groups
of elbows.
The results of open synovectomy of the elbow are generally favorable,
with 70% to 90% of patients experiencing pain relief5,7,8,17,18.
In our series, sixteen (76%) of twenty-one elbows were
mildly or not painful at the final follow-up evaluation. This finding
is within the range of results seen for open synovectomy. Our findings
demonstrated that arthroscopic synovectomy can effectively relieve
pain for a long period of time when performed in an elbow with a
preoperative radiographic grade of £3 according to the
system of Larsen et al.14.
Only a few reports have described the results of arthroscopic synovectomy
for the treatment of elbows affected by rheumatoid arthritis. In
a study of fourteen elbows treated with arthroscopic synovectomy,
Lee and Morrey reported an improvement in the mean Mayo elbow performance
score from 58 points preoperatively to 88 points at three months after
the operation and 78 points at a mean of forty-two months after
the operation11. The overall mean
improvement in the score (21.5 points) in our study corresponds
to the mean improvement (20 points) reported at the final follow-up
evaluation in the study by Lee and Morrey.
Many investigators have reported that open synovectomies, which
are often performed in conjunction with an arthroplasty that includes
radial head excision and spur resection, provide not only pain relief
but also improvement of elbow motion2,4,8,18,19.
Our data indicated that arthroscopic synovectomy does not achieve
significant improvement in the range of motion, possibly for the
following reasons. There was some preoperative restriction in the
range of motion due to the pain from synovitis, anterior capsular
contracture, and loss of joint congruence, including spur formation
and radial head deformity. In the arthroscopic synovectomy, only
the proliferating inflammatory synovial tissue was excised; the
capsule, radial head deformity, and spurs were left untreated. Therefore,
we believe that the main purpose of arthroscopic synovectomy is not
improvement of elbow motion, but pain relief. An improvement in
the ability to perform daily activities can also be expected, as
a secondary effect of pain relief.
The rate of recurrent synovitis after open synovectomy has ranged
from 16% to 43%2,4,5,20.
Few reports have provided recurrence rates after arthroscopic synovectomy.
We observed recurrent synovitis in five (24%) of twenty-one
elbows. Complete synovectomy cannot be performed with an arthroscopic
technique but can be achieved with an open technique16. Therefore, the rate of recurrent
synovitis was expected to be higher than that obtained with open
synovectomy. However, our data indicate that the rate of recurrent
synovitis after arthroscopic synovectomy is comparable with that
after open synovectomy.
The correlation between medical management of patients and the
rate of recurrence was investigated. All three patients (three elbows)
who took only nonsteroidal anti-inflammatory drugs or steroids had
recurrent synovitis. Of the seventeen patients (eighteen elbows)
who took disease-modifying anti-rheumatic drugs, only two (two elbows)
had recurrent synovitis. Control of general inflammation was poor
after the operation in those two patients. The mean time-interval
until the synovitis recurred tended to be longer in patients who
took disease-modifying anti-rheumatic drugs (mean, thirty-one months)
than it was in those who did not (mean, nineteen months). These
findings suggest that local recurrence of synovitis may be suppressed
by disease-modifying anti-rheumatic drugs.
There were no meaningful neurovascular injuries in our series,
although many previous investigators have reported a risk of damaging
neurovascular structures, such as the ulnar nerve, radial nerve,
median nerve, and brachial artery11,16,21,22.
To safely excise as much synovial tissue as possible under these
conditions, the procedure must be performed with careful attention
to detail and a thorough knowledge of joint anatomy.
Arthroscopic synovectomy presents several advantages over an
open procedure, including minimal postoperative pain, a small incision,
and no need for formal rehabilitation because it is relatively atraumatic.
Although there is a risk of neurovascular injury during arthroscopic
synovectomy and good patient selection is necessary to achieve favorable
results, this procedure can be very useful for the treatment of
elbows with rheumatoid arthritis. In conclusion, arthroscopic synovectomy for
the treatment of elbows with rheumatoid arthritis is a reliable
procedure that can effectively alleviate pain, particularly in elbows
assessed as Grade 1 or 2 according to the radiographic classification
system of Larsen et al.14.