By Chris Faubel, MD —
aka “interdigital neuroma”, “Morton’s metatarsalgia injection”, “Morton’s neuralgia injection”, “interdigital plantar neuroma injection”
- Morton’s neuroma / Morton’s metatarsalgia
- ICD-9 code:
- 355.6 “lesion of plantar nerve”
- ICD-10 code:
- G57.61 “lesion of plantar nerve, right side” – Morton’s metatarsalgia
- G57.62 “lesion of plantar nerve, left side” – Morton’s metatarsalgia
- ICD-9 code:
CPT code: 64455 “Injection(s), anesthetic agent and/or steroid, plantar common digital nerve(s) (eg, Morton’s neuroma)”
- Gloves – non-sterile
- Alcohol swabs (or betadine)
- Ethyl chloride “numbing” spray
- 25-gauge 1.5″ needle with 1-ml tuberculin syringe
- 27-gauge 0.5″ tuberculin needle with syringe – for the skin wheal
- Fill with 0.5-ml of 1% lidocaine
- 0.5ml of 6mg/ml Celestone Soluspan
- 0.5-ml of 1% lidocaine
Technique / Procedure Steps
- Always start with informed consent from the patient, and then a time-out to verify correct patient and injection site.
- Patient position: Perform lying supine with the knee flexed and the foot flat on the table.
- Mark the injection site with a pen tip to leave an impression mark.
- Clean the skin thoroughly with as many alcohol swabs as needed (usually only 1-2 are needed).
- Spray ethyl chloride or other “numbing” spray.
- With the tuberculin needle/syringe, enter nearly parallel to the skin over the injection site and create a skin wheal with 0.25ml 0f 1% lidocaine. Then advance the 0.5″ needle in the direction the injection needle with take, and anesthetize the track.
- With the 25-gauge 1.5″ needle, enter at a 45-degree angle down to the area between the metatarsal heads. Note: make sure you don’t go too far, as you may end up in the plantar fat pad and cause fat pad atrophy (but this is why I use a more water soluble steroid).
- Aspirate to make sure you’re not in a vessel.
- Once you feel you’re in the correct location, inject the full contents of the syringe. Should flow easily.
- Withdraw the needle after syringe if fully empty, and apply band-aid.
- Finding the injection site
- Press with your thumb between the metatarsal heads — most common location is between the 3rd and 4th met heads.
- Numbing the skin
- After the injection
- Have the patient move their toes around while you throw away supplies.
- Then, re-palpate at the interdigital neuroma location so they can see the immediate results of the lidocaine.
- Explain to the patient that the lidocaine will wear off in an hour or so, and that they will be back to their normal pain until the steroids start kicking in (anywhere from 1-7 days).
- May also ask the patient to not do much activity on that foot for 12 hours.