Local Anaesthetic: How It Is Used in Orthopaedic Procedures

Local anaesthetic is a medicine placed near a treatment area to temporarily reduce nerve signalling. Local anaesthetic temporarily reduces feeling in a targeted area so an orthopaedic procedure or injection can be more comfortable and informative. It does not put you to sleep, and it is different from a medicine intended to reduce inflammation.

A clinician may use it alone for a small procedure or combine it with another medicine in an injection. The amount and location are selected for the body area and planned treatment. Numbness can extend beyond the exact spot, so follow instructions about protecting the area until normal feeling returns.

Local anaesthetic acts for a limited period and may begin with warmth, tingling, pressure, or a brief sting during injection. The treated area can then feel numb or heavy. As sensation returns, mild tingling may occur. Pain relief that fades does not by itself mean the procedure failed; another medicine or the procedure's longer-term effect may have a different timeline.

In orthopaedic care, local anaesthetic may be used around a joint, tendon, bursa, spinal facet joint, nerve root, or sacroiliac joint. It can accompany a cortisone injection, an epidural steroid injection, a facet joint injection, a nerve root block, or a sacroiliac joint injection. The target and purpose differ between procedures, so the treating clinician should explain what is being injected and why.

Temporary numbness can affect movement or balance when an arm or leg is involved. Arrange safe transport and avoid demanding activity until you have been told that normal control has returned.

Some procedures use no local anaesthetic, while others may use a topical numbing medicine, a different injection plan, or sedation when clinically appropriate. Choice depends on the procedure, treatment area, medical history, allergies, medicines, and your ability to remain still. Sedation changes alertness and requires separate preparation; local anaesthetic generally keeps you awake.

Tell the clinician about previous reactions to local anaesthetic, allergies, numbness that is already present, and medicines or health conditions that may affect the procedure. During treatment, report severe pain, unusual dizziness, ringing in the ears, a metallic taste, or difficulty breathing. Afterward, protect numb skin from heat, pressure, and accidental injury until feeling returns.

The numbing effect is temporary, but its duration varies with the medicine, dose, and treatment site. Do not test numbness with heat or sharp objects, and take care not to bite or knock an area you cannot feel. Seek urgent medical help for trouble breathing, facial or throat swelling, widespread hives, fainting, seizure-like activity, or severe symptoms that begin soon after treatment. Contact the treating service if numbness or weakness lasts longer than you were told.