In the previous blog post, “non-traumatic knee pain, part I,” I discussed two common knee overuse injuries, iliotibial band syndrome and patellofemoral pain syndrome. In this blog post we are going to look into another common cause of non-traumatic knee pain, pes anserine bursitis, and discuss the infamous osteoarthritis.
Pes Anserine Bursitis
Charlotte, a 58-year-old female, 5’ 3” at 180 lbs., comes in to see you complaining of left knee pain. The pain (2/10) has been going on for about three months and is starting to become more bothersome in her day to day activities. Charlotte feels the majority of the pain on the inside of her knee. She reports no injuries. Charlotte reports five or so years ago having an x-ray done of her knees due to knee pain and was told she had mild arthritis in both of her knees. She never did anything for the pain at the time and eventually it got better until three months ago when her left knee started bothering her. Charlotte reports the pain is worse (5/10) when going from a sit to stand position or any time she has to use stairs. Walking/standing does not bother her knee. Rest and ibuprofen help with the knee pain, she reports only having to take ibuprofen a couple of times a week for the knee pain. Physical examination skin- WNL except left knee appears to have mild swelling medially compared to the right knee. Bilateral knee ROM- WNL.
Palpatory examination reveals moderate-severe tenderness to the left medial proximal tibia 2 inches below the knee joint and the area feels boggy compared to the right knee joint area. Muscle strength- hip flexion 4/5 bilaterally, knee extension 4/5 on the left, 5/5 on the right. Anterior and posterior drawer tests, Lachman test, valgus and varus stress tests and McMurray test are all negative. Charlotte has moderate restriction in flexion at the lumbosacral area and is unable to touch her toes, bilateral hamstrings are tight and left quadriceps are tight on palpation. This appears to be pes anserine bursitis. This is probably one of my favorite knee issues to diagnose and treat. Diagnosing and treating PA bursitis is like performing a magic trick to the patient. You palpate directly on the bursa and it lights the patient up like a Christmas tree, the patient then looks at you with wide eyes and says, “OUCH that hurts, how did you know to push right there?” I still giggle in my head when this happens, not because it hurts the patient (I’m not a mean person, y’all) but because the patient seems so amazed. To give the patient relief I will inject the PA bursa area at the point of maximal tenderness using a 27- gauge, 1-inch needle with 0.5mL of 1% lidocaine and 1 mL of Toradol 30 mg/mL. Literature does support a steroid injection but I use steroids as a last resort due to potential side effects. Patients get great relief with the lidocaine and Toradol. If you noticed Charlotte’s height and weight, you know that she needs to lose some weight. Obesity is one of the risk factors for PA bursitis. Educating Charlotte on weight loss and getting her the help she needs for weight loss will be huge in preventing her knee pain from reoccurring and getting worse. Also, prescribing physical therapy to help strengthen and stretch her legs will be an important piece of treatment for Charlotte.
All of us are familiar with osteoarthritis of the knee, don’t worry I’m not going to present a patient case on OA of the knee. I do, however, want to make note of something to consider. Just because a patient has OA of the knee, that does not always mean the OA is the culprit of the knee pain. While knee OA does cause pain a majority of the time, I want to stress the fact to make sure when we see these non-traumatic knee pain patients we look at other potential knee pain causes and don’t just assume it is all coming from their OA. The pain generator could be PA bursitis or they could have super tight hamstrings or IT bands that are causing the knees to hurt. Once those soft tissue issues are worked on and resolved their knee pain could resolve completely for the time being. Sure, they still have OA of the knee and as they get older it’s very likely going to progress but at least by addressing other knee pain generators the patient has an extended period of time without pain and probably increased function.