Preliminary Diagnosis: Pes Anserine Bursitis

Pes Anserine Bursitis

I. What imaging technique is first-line for this diagnosis?

  • MRI

II. Describe the advantages and disadvantages of this technique for diagnosis of pes anserine bursitis.

Advantages
  • Able to detect other causes of pain or weakness in the joint such as tendonitis, tenosynovitis, or tears of the tendons of the pes anserinus (sartorius, gracilis and semimembranosus)


    Continue Reading

  • Exclude connection to medial meniscus and joint effusion with good certainty

  • Does not make use of any ionizing radiation

Disadvantages
  • Expensive

  • Time consuming.

  • Requires significant patient cooperation to minimize motion artifact

  • Intravenous contrast requires that the patient have good renal function with a GFR greater than 60. Administration of intravenous contrast is decided individually on a case by case basis with a GFR greater than 30 and less than 60

III. What are the contraindications for the first-line imaging technique?

  • Contraindicated in patients with non–MR-compatible metallic hardware or foreign bodies

IV. What alternative imaging techniques are available?

  • Ultrasound

  • CT with or without contrast

V. Describe the advantages and disadvantages of the alternative techniques for diagnosis of pes anserine bursitis.

Ultrasound
Advantages
  • Able to detect fluid collection and whether fluid is simple or complex.

  • Optimal modality for concomitant detection and aspiration of fluid if indicated

  • Relatively inexpensive

  • Portable imaging modality

  • Does not use ionizing radiation

Disadvantages
  • Requires a skilled technician trained in musculoskeletal imaging with a high index of suspicion for detection of pathology

  • Limited evaluation in obese patients

CT with or without contrast
Advantages
  • Able to see fluid-filled bursa in its typical location

  • Further detail of bone if fracture or osseous lesions suspected

  • Performed much more quickly than MR imaging

  • Requires less patient cooperation and is associated with less motion artifact than MR imaging

Disadvantages
  • Soft tissue structures and tendons better evaluated with MRI

  • Exposes the patient to a large amount of ionizing radiation

  • Imaging with intravenous contrast requires that the patient have good renal function with a creatinine of 0.6-1.2 mg/dL for an adult

VI. What are the contraindications for the alternative imaging techniques?

Ultrasound
  • No significant contraindications exist

CT with or without contrast
  • Contraindicated in a pregnant patient, especially within the first two trimesters

  • Relative contraindication in patients with a contrast allergy

  • Relative contraindication in patients with renal failure