Plant thorn synovitis of elbow in children.

Four rare cases of plant thorn synovitis of left elbow were admitted at our institution, which were initially misdiagnosed as partially treated septic arthritis of elbow or Juvenile inflammatory arthritis. All of them were of paediatric age group. Symptoms included pain, swelling, and decreased range of motion of affected joint. On examination synovitis was present in all patients. Roentgenograms & Ultrasonography were inconclusive in all patients, Definitive diagnosis was made only after arthrotomy, Thorn fragments (Acacia arabica) were recovered from the hypertrophied synovium & subtotal synovectomy was done and sent for histopathological examination. All patients improved after surgery with mean residual flexion deformity of 12.5 ± 2.86°. Plant thorn induced synovitis of elbow is rare, it must be included in the differential diagnosis of monoarthritis of elbow and a high index of suspicion is needed for retained thorn fragments in elbow joint causing synovitis. Its optimal treatment is arthrotomy, foreign body removal and total/subtotal synovectomy.