Fluoroscopic Guided Knee Joint Injection – Technique and Overview

Name of Procedure

  • Knee joint intra-articular steroid injection
  • Supartz/synvisc/orthovisc/euflexxa/hyaluronic acid knee injection
  • Viscosupplementation

Sample Opnote

Goal

To inject a medication into the knee joint.

Indications

Depending on what’s injected, usually it is to treat pain in the knee from a variety of etiologies such as osteoarthritis.

Contraindications

Anatomy

For the purposes of a knee injection, knee anatomy is straightforward. You simply need to find the space between the femur and tibia. Other soft tissue anatomy generally doesn’t effect the procedure.

Equipment/Skills/Setup

  1. C-Arm
  2. Bed for C-Arm
  3. 25g x 1.5″ hypodermic needle
  4. Contrast
  5. 1 or 2 3cc syringes (may not need as noted below) filled with desired injectate:
    1. bupivacaine/lidocaine
    2. supartz/synvisc/orthovisc
    3. steroid (dexamethasone/triamcinolone)
  6. Prep solution
  7. Drape to keep injection site clean

Landmarks and Patient Positioning

  1. Position the patient in a basic supine position so that the bottom of the c-arm can go under the table below the knee.
  2. Bend the knees roughly 90 degrees and put a roll under it so the patient’s legs can stay relaxed. This opens up the joint space a bit. Having someone help hold the patient’s foot can be helpful.

Technique

  1. Position the C-arm in an AP orientation with the top angled slightly towards the feet.
    1. Playing with the angle will allow you to see which opens up the joint space the best.
  2. Use a pointer to find a spot directly over the joint space. We often choose just lateral or medial to the patellar ligament.
  3. Insert a 25g x 1.5″ hypodermic needle in a straight AP direction towards the joint space (“straight down the barrel”).
    1. As noted in the image, even if not directly over the joint space you can simply aim for an opening to enter the space, often in the middle of the knee.
knee with contrast spread in joint
knee with contrast spread in joint. needle entering from side to midline
  1. Inject a small amount of contrast. Ideally you see spread along the joint as in the image. A simple “blob” of contrast may mean that the needle tip is in the subcutaneous space.
  2. From here inject the desired medication based on the specific procedure that you’re doing.

Tips

  1. Usually a 25g x 1.5″ hypodermic needle is sufficient to enter the joint space. With this approach no second/larger needle is needed, and usually it can be done without local anesthetic since it’s the same needle that would be used to administer local anesthetic anyway.
    1. If it turns out that the hypodermic needle is not long enough, just inject lidocaine through it while pulling out.
    1. Then use a longer needle such as a bent quincke needle to reach the joint space.