Plant Thorn Synovitis: An Uncommon Cause of Monoarthritis

Plant Thorn Synovitis:
An Uncommon
Cause of Monoarthritis
By Thomas P. Olenginski, David C. Bush, and Thomas M. Harrington
Plant thorn synovitis (PTS) is an uncommon
cause of monoarthritis. Seven cases of PTS were
identified at our institution from January 1979 to
July 1990, six of whom were men. Mean age was
27 years (range, 7 to 56 years). Symptoms included pain, swelling, and stiffness. Synovitis
was present on examination
along with decreased range of motion of affected joints in all
patients. Roentgenograms
were unremarkable
in five patients, but disclosed demineralization
in two others. Initial conservative treatment
with
nonsteroidal
antiinflammatory
drugs
(NSAIDs), antibiotics, or splinting was usually
unsuccessful; surgery was necessary in six patients. Findings included marked inflammatory
synovial reactions with evidence of retained
thorn in all patients. One patient had a positive
P
LANT THORN synovitis (PTS) refers to
the synovial reaction caused by plant thorns
when they penetrate the joint capsule or migrate near the joint itself. Although PTS is an
uncommon clinical entity, it is an important
cause of monoarthritis that often poses a diagnostic challenge. It is not uncommon for a
patient with PTS to see several physicians before the diagnosis is entertained. Likewise, even
when considered in the differential diagnosis, a
significant period of time often elapses before
appropriate treatment ensues. From our experience at the Geisinger Medical Center with
seven cases of PTS, we describe illustrative
cases and review the literature.
PATIENTS AND METHODS
All patients included in this review were seen
at Geisinger Medical Center in Danville, Pennsylvania from January 1979 to July 1990.
From the Depatiments of Rheumatology and Orthopaedic
Surgery, Geisinger Medical Center, Danville, PA.
Thomas P. Olenginski, MD: Department of Rheumatology;
David C. Bush, MD: Depattment of Orthopaedic Surgery;
Thomas M. Harrington, MD: Department of Rheumatology.
Address reprint requests to Thomas M. Harrmgton, MD,
Department of Rheumatology, Geisinger Medical Center, Danville, PA 17822.
Copyright 0 1991 by W.B. Saunders Company
0049-0172/91i2101-0008$5.00/O
40
operative wound culture (Enterobacter agglomerans) without evidence of osteomyelitis.
All
patients improved after surgery without sequelae. Despite a history suggesting thorn injury
in many cases, diagnosis was often delayed;
mean time to diagnosis was 10 weeks (range, 2
weeks to 9 months). PTS must be included in the
differential diagnosis of monoarthritis. Histologically, PTS can mimic sarcoidosis, tuberculosis,
or fungal infection. Optimal treatment of PTS is
arthrotomy, foreign body removal, and extensive synovectomy.
Copyright 0 1991 by W.B. Saunders Company
INDEX WORDS: Plant thorn synovitis;
body synovitis; monoarthritis; arthritis.
foreign
CASE REPORTS
Patient 1
JB is a 32-year-old white man who caught his
left hand in a pricker bush and developed
progressive pain and swelling during the 5 days
following the accident. Dorsal synovitis and
pain with flexion of digits 3 and 4 were present.
He was afebrile and a complete blood cell count
(CBC) was normal. Roentgenogram of the left
hand and wrist showed soft tissue swelling. Oral
cephalexin was prescribed. He was much improved in follow-up and a wrist splint was
applied. Persistent swelling with scar tissue over
the fifth metacarpal joint and decreased flexion
necessitated the addition of tolmetin sodium.
One month later he still had persistent pain and
swelling. A firm 3 x 3-cm mass was palpated,
but did not transilluminate. He was followed for
a suspected inclusion cyst.
Eight months after the initial presentation,
the firm cystic mass was still present. Repeat
roentgenograms of the hand and wrist showed
soft tissue swelling. No fluid or material was
obtained on aspiration of the mass. At exploration 9 months after initial presentation, a large
adherent mass of granulation tissue was found,
in the center of which was yellow-brown material with an entrapped l-inch long plant thorn
spike (Fig 1). Granulation material was adherent to extensor tendons 4 and 5 and also com-
Seminars in Arthritis and Rheumatism, Vol21, No 1 (August), 1991:
pp40-46
41
PLANT THORN SYNOVITIS
Fig 1:
Operative
micrograph
showing
photo-
of patient
a large
1
plant
thorn spike and the surrounding
synovial
reac-
tion.
pletely surrounded the dorsal sensory branch of
the ulnar nerve (Fig 2). Microscopic sections
showed mixed suppurative and chronic inflammatory reaction with evidence of plant material
(Fig 3). Operative cultures grew a few Enterobacter agglomerans species, for which a short course
of oral antibiotics was prescribed. The patient
has made a complete recovery.
Patient 3
RE is a 36-year-old white man seen 6 to 7
weeks after sticking his left thumb interpha-
Fig 2:
Operative
micrograph
photo-
of patient
after completion
ovectomy
and
1
of synforeign
body removal. See adjacent nerve and tendon
structures.
42
OLENGINSKI,
BUSH, AND HARRINGTON
Fig 3:
Histologic section
(hemotoxylin
and eosin)
of operative
specimen of
patient
1.
Note
chronic inflammatory
action
and
the
re-
plant-thorn
material present.
langeal joint with a locust thorn. Pain and
swelling developed. The joint was aspirated and
cultures were sterile. Examination showed swelling and limited motion of the joint; roentgenograms were unremarkable.
Ten weeks after the initial injury, synovectomy was undertaken. At surgery, the synovium
was thick and boggy. Within a central nidus of
rather densely reactive synovium was a small
Fig 4:
Histologic section
(hemotoxylin
and eosin)
of operative specimen of
patient 3. Note the modest increase in the synovial lining cells and the
dense inflammatory infiltrate.
l-mm thorn tip. Operative cultures were sterile
and microscopic sections showed chronic nonspecific synovitis (Fig 4). A full recovery followed surgery.
Patient 7
CH is a 7-year-old white boy who fell onto a
thorn bush while playing. One week later he
developed swelling and redness at the puncture
PLANT THORN SYNOVITIS
site on his left wrist, and a thorn was “spit out.”
Roentgenograms
were negative and several
courses of oral antibiotics were ineffective.
One month later, examination showed wrist
swelling with tenderness and limited motion.
Arthrocentesis yielded 2 mL of turbid fluid.
Culture was sterile. CBC was normal and sedimentation rate was 25 mm/h. Roentgenograms
of the wrist showed demineralization (Fig 5).
The wrist was explored and synovitis was
present on both the dorsal and volar aspects.
Two small foreign bodies were found on the
volar aspect. A 4-mm long piece of thorn was
Fig 5:
43
seen within the radioscaphoid joint. Microscopic sections showed chronic synovitis and
operative cultures were sterile. He made an
uneventful recovery.
COMMENTS
This series of seven cases of PTS illustrates
several important features (Table 1). Our patients, whose mean age was 27 (range, 7 to 56
years), usually incurred injury by either working
or playing near pricker or thorn bushes. All
cases involved the hand or wrist. Symptoms
included pain, swelling, and stiffness, and find-
Normal unaffected right wrist film and demineralized
left wrist film of patient 7.
44
OLENGINSKI,
BUSH, AND HARRINGTON
Table 1: Clinical Profile of Seven Patients With Plant Thorn Synovitis
Patient
Age/Sex
Type of Injury
Location
Time Until Diagnosis
1
32/M
Pricker bush
Hand (dorsum)
9 months
2
23/M
Trimming hedges
5th MCP joint
2 months
3
36/M
Pricker bush
1st IP joint
2 months
4
56/F
Rose thorn
5th PIP joint
2 weeks
5
II/M
Thorn bush
Wrist
3 months
6
23/M
Thorn bush
2nd PIP joint
3 weeks
7
7/M
Thorn bush
Wrist
1 month
ings included synovitis with decreased range of
motion of involved joints.
Roentgenograms were unremarkable in five
cases, but did show demineralization
in two.
Conservative treatment with nonsteroidal antiinflammatory drugs (NSAIDs) and splinting
with or without antibiotics was usually unsuccessful; surgery was necessary in six cases. Findings
at surgery included marked inflammatory synovial reactions with evidence of retained thorn
material. One case had associated infection
(positive operative wound culture with Enterobacterugglomeruns) without evidence of osteomyelitis. Synovial histopathology demonstrated synovitis and often plant material. All patients had
complete resolution of symptoms after surgery.
Despite a history suggesting thorn injury in
many cases, diagnosis was often delayed. Mean
time to diagnosis in our series was 10 weeks
(range, 2 weeks to 9 months).
DISCUSSION
In 1966, Kelly reported 24 cases of blackthorn
inflammation and their associated clinical manifestations.’ As reported, the blackthorn (Prunus
spinous) is a perennial shrub in the British Isles
that bears narrow thorns up to 2$!!-inches long
that can penetrate the skin, break off, and
remain embedded in tissues or joints. Pathologically, a chronic foreign body reaction may
ensue and lead to chronic monoarthritis, chronic
bursitis, soft tissue foreign body cysts, chronic
tenosynovitis, or other soft tissue inflammation.
In Kelly’s report, all cases involved the appendicular skeleton. Symptoms included pain, local
tenderness, and swelling. Antibiotic therapy
provided symptomatic relief, but patients were
never cured. When the joint was involved,
synovitis with effusion, heat, and decreased
range of motion were often present. A considerable delay (average, 10% weeks) was noted from
the time of injury until patients sought medical
advice. Roentgenograms were of little help in
this group of patients, although they excluded
obvious bony destruction. Treatment was surgical with prompt resolution of symptoms after
foreign body removal. In only one case reported
by Kelly was there associated infection (positive
operative wound culture without evidence of
osteomyelitis).
Sugarman et al in 1977 reported a group of
five patients with inflammatory monoarthritis
due to joint penetration by palm thorns.’ The
authors noted that the date palm (Z’hoenk
dactylifera and Phoenix canariensis) and sentinel
palm (Washingtonia fififera) were most commonly involved. However, reports of injury with
Yucca afoifolia and the rose thorn were described. All patients were young (ages 4 to 7
years), and three of five cases had associated
infection (growth from synovial fluid cultures)
without evidence of osteomyelitis. Often the
history of thorn injury was forgotten. Antibiotics alone were ineffective in alleviating symptoms. A transient acute synovitis was followed
by a relatively asymptomatic period, and later
chronic arthritis. Three patients had inflammatory synovial fluid; one had noninflammatory
fluid. One patient’s roentgenograms showed a
lucent lesion of the femoral condyle surrounded
by sclerotic reaction and epiphyseal overgrowth.
At surgery, massive synovial hypertrophy had
eroded the femoral condyle producing a 1.5-cm
bony cavity. In the other cases, marked synovial
thickening was seen with pannus formation. At
times the plant thorn material was grossly evident; even when not seen, it was often microscopically visible on histologic sections. Periodic
acid-Schiff (PAS) staining and polarizing light
facilitated identification of plant material. Histologically, the granulomatous
reaction was
thought to resemble the appearance of sarcoido-
45
PLANT THORN SYNOVITIS
tuberculosis, or fungal disease. Joint function of all five patients was normal in follow-up.
A second surgical procedure was necessary in
one patient because not all of the plant material
was removed and recurrent symptoms developed.
The need for wide exposure and removal of
all plant material was emphasized in the report
of Cahill et al in 1984.3 They described 10 cases
of PTS, two with associated infection (positive
synovial fluid cultures), but without evidence of
osteomyelitis. Nine of their cases had knee
involvement. Mean age was 7 years and mean
delay in diagnosis was 10 weeks. Synovial fluid
was markedly inflammatory (mean synovial fluid
white blood cell count 34,300 with 79% polymorphonuclear neutrophil leukocytes). Ten operations were performed in this series, with three
extensive synovectomies, six limited synovectomies, and one synovial biopsy. Three of seven
patients undergoing limited synovectomy required subsequent surgery with more extensive
synovectomy and foreign body removal. The
authors recommended arthrotomy, foreign body
removal, and extensive synovectomy for PTS.
Carandell et al supported this view in their 1980
case report.4
Most reports on PTS have suggested that
roentgenograms are of limited diagnostic benefit. They often show soft tissue swelling and/or
effusion but not foreign bodies. They are clearly
helpful in excluding bony destruction suggestive
of tumor or infection. However, Gerle in 1971
discussed thorn-induced pseudotumors of bone
and suggested that the appearance could mimic
neoplasms with either osteolytic or periosteal
reaction.’ At that time, seven examples of such
pseudotumors primarily involving pediatric patients had been described. This finding had
been noted earlier by Maylahn et al in 1952,h
Weston in 1963,7 and Borgia et al in 1963.’
Interestingly, Cahill et al reported that a pseudotumor appearance with smooth, sclerotic margins can be seen in rheumatoid arthritis, pigsis,
mented villonodular synovitis, and hemophilic
arthropathy.3 They suggested including Ewing’s
sarcoma, osteosarcoma, osteoid osteoma, stress
fracture, osteomyelitis, bone cysts, enchondroma, and giant cell tumor in one’s differential
diagnosis of such a pseudotumor appearance on
roentgenogram.
It is of interest and therapeutic significance
that in cases of PTS with positive synovial
and/or operative cultures that osteomyelitis has
not been described frequently. However, in
1988, Vincent et al reported a case of Enterobacter agglomerans osteomyelitis of the hand from a
rose thorn injury.9 Therefore, when making a
diagnosis of PTS, one must exclude superimposed osteomyelitis.
Most recently, in 1990, Reginato et al described 26 patients with foreign body synovitis,
12 of whom had thorn synovitis.“’ Several thorns
were implicated including Uleux europaeus thorn,
blackbush thorn, citrus thorn, rose thorn, Rubus
jkucticous thorn, Agave americans thorn, cactus
thorn, and palm thorn. Two cases had associated erosive changes on roentgenograms. Most
patients needed exploratory surgery to identify
and remove the causative thorn.
In conclusion, PTS is caused by joint injury
with plant thorns. A number of thorns have
been implicated. Because patients often forget
to mention a history of thorn injury and physicians fail to consider PTS, diagnosis is frequently delayed. This review highlights the need
to consider PTS in the differential diagnosis of
monoarthritis. The symptoms of PTS can mimic
those seen in other inflammatory arthritides. As
there is no specific diagnostic test for PTS,
when the history suggests thorn injury and
arthritis is evident, the diagnosis should be
established surgically. The recommended procedure of choice is arthrotomy with foreign body
removal and extensive synovectomy. Patients
approached in this fashion uniformly improve
and maintain normal joint function.
REFERENCES
1. Kelly JJ: Blackthorn
inflammation.
J Bone Joint Surg
31474.477, 1966
4. Carandell M, Roig D, Benasco
tis. J Rheumatol4:567-569,
1980
2. Sugarman M, Stobie DC, Quismorio
FP, et al: Plant
thorn synovitis. Arthritis Rheum 5:1125-1128, 1977
5. Gerle RD: Thorn-induced
Radio1 44:642-645, 1971
3. Cahill N, King JD: Palm
Orthop 2:175-179, 1984
6. Maylahn DJ: Thorn-induced
Bone Joint Surg 2:386-388, 1952
thorn
synovitis.
J Pediatr
C: Plant thorn
pseudotumors
tumors
synovi-
of bone. Br J
of the bone.
J
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OLENGINSKI,
7. Weston WJ: Thorn and twig-induced
pseudotumors
bone and soft tissues. Br J Radio1 425:323-326, 1963
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foreign
CA: An unusual
bone
body in the hand. Clin Orthop
9. Vincent
reaction
of
to an organic
30:188-193,
K, Szabo RM: Enterobacteragglomerans
1963
osteo-
BUSH, AND HARRINGTON
myelitis of the hand from a rose thorn: A case report.
Orthopedics
3:465-467,1988
10. Reginato
AJ, Ferreiro
JL, O’Connor
CR, et al:
Clinical and pathological studies of 26 patients with penetrating foreign body injury to the joints, bursae, and tendon
sheaths. Arthritis Rheum 12:1753-1762,199O