Musculoskeletal Section | Imaging Procedures
Hip Aspiration or Injection
- Contrast injection for MR Arthrogram: Typically ordered for evaluation of possible labral tear.
- Anesthetic Hip Arthrogram: In patients with lumbar spine and hip disease to prove if pain is coming from hip.
- Diagnostic/Therapeutic Arthrogram: This procedure is done to determine if the hip is the cause of a patient’s pain and to treat the pain.
- Rule Out Septic Arthritis:
- Status-post hip arthroplasty
- Obtain signed consent.
- Place the hip in internal rotation with partial flexion with padding under the knee and a sandbag holding the foot.
- Mark the lateral margin of the course of the femoral artery using a marking pen.
- Target a few mm inside the lateral junction of the femoral head and neck and confirm that the femoral vessels are out of the way.
- Prep and drape with aperture drape and towels.
- Anesthetize the skin and subcutaneous tissues with buffered 1% lidocaine.
- The remainder of the procedure depends on the indications:
- Hip MR Arthrogram and Hip Injections:
- A 22 G 3½” needle is used for all MR arthrogram injections as well as for anesthetic arthrograms.
- Place the tip of the needle directly onto the anterior cortex at the spot marked.
- Confirm intraarticular needle placement with a small injection of Omnipaque 300 and take a spot film (Figure 1).
- MR Arthrogram – Inject 10–20 cc of a the standard dilute gadolinium MR arthrogram solution (10 cc normal saline, 5 cc Omnipaque, 5 cc 1% lidocaine, and 0.1 cc gadolinium)
- Anesthetic Arthrogram – Inject 8 cc of a mixture equal parts 2% lidocaine and 0.5% Bupivacaine.
- Diagnostic/Therapeutic Injection – Inject 1 cc of Celestone (6 mg) and 1-2 cc 0.5% Bupivacaine.
- Adult Hip and Hip Arthroplasty Aspirations to Rule Out Infection:
- Generally, a 3 ½” 18 G needle is used for all adult arthrograms to rule out infection including hip arthroplasy aspirations. This is because the synovial fluid can be very thick especially if infected.
- Aim for the lateral edge of the prosthesis from a slightly lateral approach. Feel it touch the metal, advance it past the prosthesis, and aspirate as you pull back.
- The joint pseudocapsule can be heavily calcified simulating bone, be sure to feel metal.
- Aspirate the joint with a 20 cc syringe.
- If the tap is dry (especially in hip replacements): Inject a small amount of Omnipaque 300 mg under fluoro to insure proper intraarticular needle placement (Figures 2 and 3).
- Inject 10 cc of sterile normal saline.
- Aspirate the injected saline.
- Inject the fluid into culture tubes, anaerobic and aerobic.
- Pediatric Hip Aspirations:
- The needle size is tailored to the size of the patient.