ESTES PARK, COLO. – Anserine bursitis is a common overuse injury frequently misinterpreted as osteoarthritis, according to Dr. Robert W. Janson.
The pain is focused at the medial aspect of the knee about 2 inches below the tibial plateau, or joint line. The bursa is located at the anatomic site known as the pes anserinus, or goose foot, where the conjoined tendons of the semitendinosus, gracilis, and sartorius muscles insert at the tibia, Dr. Janson explained at a conference on internal medicine sponsored by the University of Colorado.
"How do you find this bursa? It’s very easy. Take two fingers, grab the hamstring, and just run the two fingers down until they meet and you’re right there," said Dr. Janson, a rheumatologist at the university.
An affected patient will report the pain is worse with stair climbing or lying on one side with the knees opposed.
"Obese women with valgus knees tend to get this injury a lot," according to Dr. Janson.
Other risk factors for anserine bursitis are gait abnormalities or running and jogging.
Management is via the general measures utilized in treating overuse syndromes: rest, ice or heat, full-dose NSAIDs, and hamstring stretching.
If the pain persists for 6-8 weeks, a local injection of 10-20 mg of methylprednisolone with 1% lidocaine is enormously helpful. Find the tender area, mark it, direct the needle down to the bone, then back off about 1 mm and simply infiltrate that area, the rheumatologist advised.
He reported having no relevant financial conflicts.