Case # 2 - Knee Pain in a Sprinter
Disclaimer: The following case is for education purposes only and does not depict any actual person or patient.
A 19-year-old male track athlete reports having right knee pain for 3 years. He states that he cannot recall any traumatic injury to the knee. In general, he has no pain at rest or during normal activities of daily living. His primary events in track are sprints and long jump. He specifically notes pain with sprinting as well as landing his long jump. He reports that the pain limits his performance in track.
On physical exam, the young man is well appearing and well developed. He has a normal gait pattern with no noticeable limp. He has full range of motion and no swelling or effusion of the knee. Tenderness to palpation is noted over the anterior knee including tibia tuberosity and patella tendon. No pain is elicited with varus and valgus stress or patellar grind of the knee. He has normal special testing with a normal Lachman test and McMurray test.
A normal x-ray was obtained in clinic and followed up by a bedside MSK ultrasound of the anterior knee.
Anterior Knee MSK Ultrasound
What criteria do I use to make the diagnosis of patella tendinopathy?
I use a combination of clinical history, physical exam, and imaging to confirm the diagnosis. First, I am looking for the patient to have pain for greater than 3 months, which helps to establish the pain being chronic in nature. On exam, the most consistent site of pain for patella tendinopathy is directly over the patella tendon just below the lower edge of the knee cap. Lastly, I like to confirm the diagnosis with direct ultrasound visualization of degenerative tissue and hypervascularity within the tendon itself.
What is my treatment algorithm?
My recommendation on a plan of action for patella tendinopathy really depends on the individual situation. If it is relatively early on and the patient hasn’t tried much in the way of therapy, I usually will give them a trial of physical therapy for 4 to 6 weeks utilizing eccentric exercises and dry needling. If they fail a trial of physical therapy or have had symptoms for years I will recommend an ultrasound-guided needle tenotomy. Essentially, under ultrasound guidance, we will take an 18 G needle and pass it through the area of tendinosis to stimulate an inflammatory reaction within the tendon to hopefully improve pain. The tenotomy procedure can be augmented with injecting PRP or hypertonic saline to try to improve the response. I am aware of other techniques where providers will use normal saline to dissect away the underlying Hoffa's fat pad which is thought to contribute to the condition.
Consider patella tendinopathy in older teenagers with proximal patella tendon pain that is persistent for several months or even years.
Patella tendinopathy is not an inflammatory process, therefore treating it the same as patella tendonitis will likely not result in improvement of the condition.
If tendinosis is identified under ultrasound visualization, the doppler setting can be used to visualize neovascularization within the tendon, consistent with the diagnosis (see below).
It is not recommended to inject a corticosteroid into a tendon due to an increased risk of rupture.