This week, a 13-year-old female year came into the clinic with her mother and had a chief complaint of “left knee pain”. During the health history, the patient states she has had posterior knee pain x 2 weeks. No injury or trauma. Pain increases with flexion and standing. Patient denies redness, swelling, numbness or tingling to left leg and foot. Upon physical examination, the patient had a negative McMurray’s, anterior drawer, posterior drawer, and Steinman’s tests. I palpated a moveable, nontender mass behind that patient’s medial posterior knee. As I presented the case to my clinical instructor, my differential diagnoses were Baker’s cyst, tendinitis, and deep vein thrombosis. After my clinical instructor assessed and talked to the patient and her mother, he stated the diagnosis was Baker’s cyst.

A Baker’s cyst is swelling in the popliteal fossa due to an enlargement of the gastrocnemius-semimembranosus bursa (Burns, 2017). In adults, Baker’s cysts are often secondary to degenerative or inflammatory joint injury; while in children, they are usually uncommunicative with the joint space and considered a primary process (Fenstermacher & Hudson, 2016). A diagnosis can be made based on the physical assessment or if no mass is felt an XR or ultrasound can be ordered. Baker’s cysts in children often resolve on their own with no additional treatment. In symptomatic patients, arthrocentesis and intraarticular injection of the affected joint with glucocorticoids can be used as treatment. In our patient’s case, my preceptor wanted the patient to take Ibuprofen 400mg PO Q6hr for pain, continue with normal activity, and ice posterior knee for 30 minutes 2-3 times a day. The patient will follow up in 2-3 weeks for reassessment and possible orthopedic referral if symptoms are not relieved.


Burns, C. E. (2017). Pediatric primary care. St. Louis, MO: Elsevier.

Fenstermacher, K., & Hudson, B. T. (2016). Practice guidelines for family nurse practitioners. Philadelphia, PA: Elsevier.