Forty-five knees (thirty patients) with a specific diagnosis of synovial
plica syndrome, and without any other known lesion, were randomized to be
treated with either diagnostic arthroscopy alone or arthroscopy and
division of all plicae. The diagnosis of synovial plica syndrome had been
made on the basis of intermittent pain in the anterior aspect of the knee,
painful clicking with activity, giving-way, and a palpable, tender plica.
The patients were selected for arthroscopy only if the symptoms had
continued unabated after a course of physical therapy. At the time of
follow-up, improvement had occurred in only six (29 per cent) of the
twenty-one knees in which the plicae had not been divided, in contrast with
twenty (83 per cent) of the twenty-four knees in which they had been
divided (p < 0.001). Ten (48 per cent) of the knees in which
arthroscopic division had not been done were treated with another
arthroscopic operation. Seven of these ten knees improved after the
subsequent division of the plicae (p < 0.01). We concluded that synovial
plicae of the knee may be a definite cause of anterior pain in children and
adolescents.