Merck Manual

Please confirm that you are a health care professional

honeypot link

How To Remove a Cast


James Y. McCue

, MD, University of California San Francisco - Fresno

Last full review/revision Jun 2021| Content last modified Jun 2021
Click here for Patient Education
Topic Resources

Casts should be removed by professionals using appropriate equipment.


  • Completion of the period of immobilization

  • Numbness, tingling, increasing pain, or any other sensation indicating the cast is too tight

  • Foreign body lodged between the skin and the cast

  • Cast damage or wetness

  • Concern about infection under the cast


  • A date that is before the prescribed period of immobilization


  • Injury to underlying skin (eg, abrasions, friction burn)


There are several different tools that can be used to remove a cast:

  • Vibrating cast saw

  • Cast spreader

  • Blunt-tipped shears

Vibrating cast saws look like they could easily lacerate the skin, but they are quite safe.

Additional Considerations

  • Use a sheet or drape to collect dust generated from cutting the casting material.

  • If the cast saw has an attached vacuum hose, use it to collect the dust.

  • Wear appropriate eye and respiratory protection to protect against flying cast debris.


  • The patient should be positioned to provide the operator with optimal access to the extremity with the cast.

Step-by-Step Description of Procedure

  • Introduce the vibrating cast saw to the patient, and touch it to your own palm to demonstrate that it does not hurt and will not cut the skin.

  • Score the cast along its long axis.

  • Continue cutting the cast in the channel created by scoring until the underlying padding is reached.

  • Cut the padding and stockinette with blunt-tipped shears.

  • Insert the cast spreader between the cut cast edges.

  • Spread the cast apart using the cast spreader.

  • Remove the cast.


  • Clean the extremity of accumulated dried skin and oils using soap and water.

  • Arrange or recommend appropriate physical therapy if needed (eg, for joint stiffness).

Warnings and Common Errors

  • To avoid injury to the underlying skin, do not continue to apply pressure with the cast saw at the same location after cutting through the plaster or fiberglass.

Tips and Tricks

  • Spreading the cast apart may be easier if both sides are cut rather than just one side.

  • Brace part of the hand holding the cast cutter on the cast for better control.

Click here for Patient Education
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version
Professionals also read
Test your knowledge
Traumatic Brain Injury
A 10-year-old boy is brought to the emergency department via ambulance after he was involved in a motor vehicle collision. The patient is unconscious on arrival. Glasgow Coma Scale (GCS) score is 8/15. MRI shows small microhemorrhages in the brain stem. The patient remains unconscious for the next 7 hours. Based on these findings, which of the following is the most likely diagnosis? 
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID

Also of Interest