Date Palm Synovitis

Date Palms




The date palm is common in the Sultanate of Oman and neighboring Gulf countries. The history goes back 600 years to Eridu in lower Mesopotamia where the first evidence of date cultivation has been found. Closer to this oasis, the Hilli settlements of Al-Ain in the Arabian Peninsula seems to be cultivated dates some 5000 years back. In Bidiyah, in the eastern region of the Sultanate of Oman, dates are the main-stay of the economy. Date growing is labor intensive in Oman and very traditional in its method.

To fertilize the female flowers (pistils), each date palm must be climbed and the pistils, which are clustered to the center of the leaves, pollinated. Each date palm provides the farmer with natural steps to climb the trunk. These are formed from the base of the previous season’s leaf stalks which were cut off. The technique of climbing is simple but since a date palm can be 30 meters tall, a key requirement is good head for height. The worker has to climb the tree once more in the later months in order to obtain the fruit that is now ready to be harvested.

Synovitis

Synovitis is the medical term for inflammation of the synovial membrane. This membrane lines joints which possess cavities, known assynovial joints. The condition is usually painful, particularly when the joint is moved. The joint usually swells due to synovial fluid collection.
Synovitis may occur in association with arthritis as well as lupus, gout, and other conditions. Synovitis is more commonly found in rheumatoid arthritis than in other forms of arthritis, and can thus serve as a distinguishing factor, although it can present to a lesser degree in osteoarthritis. Long term occurrence of synovitis can result in degeneration of the joint.

Date Palm Synovitis

Joint inflammation associated with intra-articular retention of a date palm thorn.

Synonyms

Date Palm Knee

Incidence

Uncommon in the northern hemisphere and in developed countries. It is much more common in Sultanate of Oman and neighbouring Gulf countries where traditional agricultural practices require climbing palm trees. Because the original injury may have been forgotten, this diagnosis should be considered in mono-articular inflammation in children.

Differential Diagnosis

Septic arthritis

( This can be differentiated by doing a simple blood investigation.
There will be normal WBC and ESR in Date Palm Synovitis, meanwhile in septic arthritis there will increase in both WBC and ESR)

Pathogenesis

A penetrating injury into the joint (usually the knee) results from a minor wound from a the thorn. The date palm tree bears thorns 10-15cm long, which can easily pierce the joint cavities.



If the thorn breaks off inside the joint, an acute, sub-acute or chronic inflammation of the joint may result. Many infective agents have been associated with date palm thorn. with no one predominating bacterium. Staphylococcus aureus has been found commonly but this is thought to be secondary infection following attempts at self-treatment.

Pathology

The arthritis may be either septic or sterile. It is unknown whether the primary features are due to infection or to an immune response to the foreign material in the vegetable matter. The reason for this is not clear, but alkaloids in the thorns are a possible cause (Stromqvist, Edlund and Lidgren 1985). The pathological features are those of acute inflammatory synovitis. Chronic synovitis develops if the condition persists.

Macroscopically,
• Redness, swelling, tenderness, loss of range of motion
• May settle to a chronic effusion with thickened boggy synovium
• May progress to a septic arthritis. There may also be a soft tissue infection leading to fasciitis. Examine for local, distant and systemic signs of infection – pyrexia, malaise, lymphadenopathy, cellulitis
• Rare presentation as locking, mimicking IDK with the thorn itself causing the locking




Microscopically,


Synovium from to two cases requiring partial synovectomy showed a non-specific synovitis. (Haematoxylin and eosin)



Synovial tissue from knee of patient with thorn-induced synovitis (hematoxyline- phloxine-saffron). Top: Heavy fibrin deposits (F) on surface and intenae infiltration of inflammatory cell (original maginification x 120, reduced approximately 25%). Bottom: Foreign material (arrow) in synovium, surrounded by numerous giant cells, seen under polarized light, material is highly refractile, consistent with plant thorn matter (original magnification x 540)

Stages

Acute
Infected
Inflammatory
Sub-acute (> 1 week)
Chronic
Non-specific

Classification

None encountered in the literature. Useful classifications could be devised using time, aetiological agent, infected/sterile or extent of the condition.

Clinical Features

Palm thorn synovitis is usually mild, the initial symptoms are often intolerated, delaying presentation for treatment.
The clinical features are:

• Puncture wound or history (may be absent)
• Redness, swelling, tenderness, loss of range of motion
• May settle to a chronic effusion with thickened boggy synovium
• May progress to a septic arthritis. There may also be a soft tissue infection leading to fasciitis. Examine for local, distant and systemic signs of infection – pyrexia, malaise, lymphadenopathy, cellulitis
• Rare presentation as locking, mimicking IDK with the thorn itself causing the locking

Investigation

CRP, aspiration and culture may identify an infective process and an organism but treatment of the infection may not resolve the problem unless the presence of the foreign body is detected. But normally, the WBC and ESR is within normal limits and no organisms was grown from any joint aspirate.

Depending on the stage fluid aspirated from the joint will have acute or chronic inflammatory cells but other rheumatological investigations will be negative.
Xrays are most often negative apart from a synovial effusion as thorns cannot be seen on radiographs. CT scan has been claimed to be diagnostic. MR scan is reliably diagnostic for this condition as the foreign body ( thorns) shows up well.

Prognosis untreated

In the acute infected case the prognosis is that of acute septic arthritis
For sterile cases and indolent infections the condition may settle to a chronic mono-arthritis with eventual secondary OA.
Since the condition is provoked by the presence of foreign material it will not settle completely until the foreign material is removed or eliminated.

Non-Operative Treatment

Appropriate antibacterial treatment.
Symptomatic treatment with analgesics and anti-inflammatory medication.
Steroid injection contra-indicated

Operative Treatment

Transarthroscopic excision of the loose body
Open or transarthoscopic synovectomy
Surgical treatment of septic arthritis

Complications

Chronic arthritis
Secondary OA
Sepsis

Outcomes

Favourable outcome after early recognition and surgical treatment
Literature suggests that synovectomy may be necessary after development of chronic synovitis i.e. that removal of the foreign body may not be enough.

Bibliography

1. Clough J.F.M. (1999) Cactus Knee Orthopaedic Rare Conditions Internet Database (ORCID) http://www.orthogate.org/orcid/aspercases.htm
Has an extensive bibliography on this subject

2. Maillot F, et al.
Plant thorn synovitis diagnosed by magnetic resonance imaging.
Scand J Rheumatol. 1994;23(3):154-5.


3. Doig SG, et al.
Plant thorn synovitis. Resolution following total synovectomy.
J Bone Joint Surg [Br]. 1990 May;72(3):514-5.

4. Klein B, et al.
Thorn synovitis: CT diagnosis.
J Comput Assist Tomogr. 1985 Nov-Dec;9(6):1135-6.


5. Ramanathan EB, et al.
Date palm thorn synovitis.
J Bone Joint Surg [Br]. 1990 May;72(3):512-3.

6. Olenginski TP, et al.
Plant thorn synovitis: an uncommon cause of monoarthritis.
Semin Arthritis Rheum. 1991 Aug;21(1):40-6.


7. Vaishya R.
A thorny problem: the diagnosis and treatment of acacia thorn injuries.
Injury. 1990 Mar;21(2):97-100.

8. Adams CD, Timms FJ, Hanlon M.
Phoenix date palm injuries: a review of injuries from the Phoenix date palm treated at the Starship Children's Hospital. Aust N Z J Surg. 2000 May;70(5):355-7.


9. Miller EB, Gilad A, Schattner A.
Cactus thorn arthritis: case report and review of the literature.
Clin Rheumatol. 2000;19(6):490-1.

10. Labbe JL, Bordes JP, Fine X.
An unusual surgical emergency: a knee joint wound caused by a needlefish. Arthroscopy. 1995 Aug;11(4):503-5.

This article was contributed by Ms Maisrah as an e learning exercise