Ultrasound useful for orthopedic patients

By Adam Smith, M.D.

Ultrasound imaging has been used in many surgical subspecialties to assist with diagnosis and management of medical conditions. Its use in orthopedic conditions has been gradually expanding. Your West Tennessee Bone & Joint Clinic provider may use this technology to diagnose injuries to tendons or muscle, or to assist with minor procedures such as injections.

Let’s review the basics of diagnostic ultrasound and its potential uses in orthopedic patients …

How does ultrasound work?

  • A handheld transducer is used by the surgeon on the affected part. The transducer emits high frequency sound waves.
  • These sound waves travel into the body tissues. Millions of pulses and echoes are sent and received each second.
  • Tissues have differing densities and reflect or absorb these sound waves differently. For example, bone completely reflects the sound waves, and normal knee fluid allows the sound waves to pass through unreflected.
  • The reflected waves are picked up by the probe and relayed to the computer, which calculates distance from the probe to the tissue based on the time of each echo's return (millionths of a second).
  • The machine displays the distances and intensities of the echoes on the screen, forming a two-dimensional image.
  • The probe can be moved along the surface of the body and angled to allow for the best possible view of the damaged structure.

Why is ultrasound useful?

  • Ultrasound is non-invasive and not painful.
  • Ultrasound has no harmful radiation.
  • Ultrasound is relatively inexpensive compared to MRI or CT.
  • Ultrasound is dynamic. This means that joints, muscles and tendons can move during the exam, allowing your surgeon to assess the injury in different positions.
  • Ultrasound is frequently used to guide injections. While many injections have been done based on superficial and palpatory anatomy, dynamic ultrasound guidance may be indicated to allow for increased injection accuracy.

Dynamic ultrasound imaging can be used to assist with diagnosis and management of musculoskeletal injuries. It allows for “real-time” assessment of injuries and is cost-effective.

While ultrasound is extremely useful, many injuries still require other options, such as MRI to maximize imaging accuracy. Feel free to discuss these options with your surgeon.