What Is a Nail Spicule?
A nail spicule is a very small, narrow fragment of nail that continues growing after a previous ingrown toenail procedure.
Although it may only be a few millimetres wide, it behaves exactly like a normal nail.
As it grows, it can penetrate the surrounding skin and recreate all the symptoms of the original ingrown toenail.
Because nail spicules are so small, patients often cannot see them themselves.
How Does a Nail Spicule Develop?
The nail grows from specialised tissue beneath the skin called the nail matrix.
During a permanent nail procedure, the aim is to permanently stop the small section of matrix producing the troublesome nail edge.
Occasionally, a tiny portion of that matrix survives.
Even though it is very small, it can continue producing a thin strip of nail.
That thin strip becomes a nail spicule.
What Symptoms Does It Cause?
Patients often describe symptoms that sound very familiar.
These include:
- Pain in exactly the same corner.
- Tenderness when wearing shoes.
- Swelling.
- Intermittent drainage.
- Recurrent infection.
- Bleeding.
- The feeling that "something sharp" is growing under the skin.
The symptoms may develop gradually over several months after what initially appeared to be successful surgery.
Why Is It Sometimes Difficult to Diagnose?
Nail spicules can be surprisingly difficult to identify.
Reasons include:
- They are extremely narrow.
- They may remain hidden beneath swollen skin.
- Scar tissue may obscure the nail edge.
- Infection may conceal the underlying cause.
Careful examination under good lighting is often required.
Occasionally, gentle exploration of the nail groove identifies the offending nail fragment.
Is It Common?
Fortunately, no.
Permanent ingrown toenail procedures are highly successful.
However, because no medical procedure has a 100% success rate, a small number of patients develop nail spicules following surgery.
Most clinicians performing large numbers of nail procedures will encounter this occasionally.
Can It Be Prevented?
Meticulous surgical technique significantly reduces the likelihood of nail spicules developing.
This includes:
- Accurate identification of the nail matrix.
- Appropriate treatment of the intended matrix.
- Careful inspection before completing the procedure.
Despite careful technique, recurrence remains possible because biological healing varies between individuals.
How Is It Treated?
Treatment depends on the severity of symptoms.
Options may include:
- Observation if asymptomatic.
- Removal of the nail spicule.
- Revision partial nail avulsion.
- Repeat matrix procedure if ongoing nail growth is present.
The goal is to permanently eliminate the small remaining nail fragment while preserving the healthy nail.
Evidence Update
Residual nail matrix producing nail spicules is recognised as one of the leading causes of recurrence after permanent nail surgery. Revision procedures addressing the residual matrix generally achieve excellent outcomes.
Patient Tip
If pain returns months after successful surgery in exactly the same location, ask whether a nail spicule could be responsible.