Podiatry Coding & Billing Alert

ICD-10 has simplified reporting for bunions and hallux valgus.

Don’t let anatomic terminology trip up your foot and ankle claims. As long as you know the specifics of each condition in this category, you too can code foot and ankle services like an ace.

Toe, foot and ankle problems can be caused by wear-and-tear, or by sudden injuries, such as those from jumping during sports. You’ve got to know the differences between these diagnoses, or you may miss a subtle difference and assign the wrong code.

Coding tip: One thing to remember is that you might need modifiers to help differentiate work on different areas of the feet or toes. These modifiers include LT (Left side) and RT (Right side), TA-T9 (for the individual toes), and sometimes 59 (Distinct procedural service) or the new EPSU codes, depending on the service your orthopedist provides. These modifiers become particularly important if the physician performs the same procedure on more than one foot or toe.

This ready reckoner will help find your foot, ankle and toe diagnosis codes on the fly.

Bunions and Hallux Valgus Now Mean the Same

A bunion is an enlargement of bone or tissue around the metatarsophalangeal (MTP) joint. It is often made worse by patients wearing shoes that are too narrow around the toe box and can cause pain and worsen deformity of the toes.

ICD-10 has removed the difference between the two conditions and now “hallux valgus” and “bunion” are the same thing. Earlier there were two different codes 727.0 (Synovitis and tenosynovitis) and 727.1 (Other disorders of synovium, tendon, and bursa; bunion) that differentiated a deformity such as bunion with the specific “overlapping of great and second toes” of a hallux valgus. However, in a merged description, if you now look up M20.1- (Hallux valgus [acquired]), the definition reads, “Hallux valgus, or bunion, a progressive deformity of the right foot that is not inherited, involves lateral, or sideways, movement of the great toe towards the second toe and deformity of the bone of the first metatarsophalangeal joint, the joint where the head of the metatarsal bone attaches to the first bone of a toe.”

Therefore, in the simplified update, you can report M20.1- even if you are not sure that the patient had a great toe angled in so far that it actually overlapped the other toes. CPT^® also lists bunion procedure codes, such as 28290 (Correction, hallux valgus [bunion], with or without sesamoidectomy; simple exostectomy [e.g., Silver type procedure]), as “hallux valgus corrections.” Physicians who perform these are correcting a hallux valgus, according to CPT^® terminology.

Some coders may be tempted to use M20.6- (Acquired deformities of toe[s], unspecified) to specify a bunion without hallux valgus, but this is incorrect. Because a more specific code is available M20.1-, use that instead.

Above all, if you’ve been coding 735.0 — or even 727.1 — with all bunionectomies, replace them with the unified ICD-10 code as this also simplifies the confusion with your payers to see whether the earlier minor discrepancy made a difference.

Differentiate Between Hammer Toes and Claw Toes

A hammer toe is a deformity of a toe in which the proximal phalanx extends and the second and distal phalanges flex, causing a clawlike appearance (usually the second, third or fourth toe). You know it’s time to reach for a hammer toe code:

• Acquired: M20.4- (Other hammer toe[s] [acquired]…)
• Congenital: Q66.89 (Other specified congenital deformities of feet)

if you find a description such as “toe has a flexion contracture (fixed or flexible) at the PIP (proximal interphalangeal) joint.”

However, don’t confuse this condition with claw toe:

• Acquired: M20.5X- (Other deformities of toe[s] [acquired]…)
• Congenital: Q66.89

Some coders may consider M21.53- (Acquired clawfoot) as another alternative to acquired claw toe diagnosis. “However, I would use M20.5X- since M21.53- refers to the entire foot,” says Arnold Beresh, DPM, CPC, of Peninsula Foot and Ankle Specialists PLC in Hampton, Va. There is a subtle difference between hammer toe and claw toe. A claw toe has a flexion contracture at the PIP joint, as well as an extension contracture at the MTP joint.

The most common causes of hammering are a constricted toe box that compresses the toes, chronic flexor digitorum tightness, diabetes and seronegative disease, disease-based muscle imbalance, and mild compartment syndrome following tibial and foot fractures.

How you code the treatment depends on whether the physician diagnoses the deformity as fixed or supple.

Supple hammer toe: Podiatrists will often use a tenotomy to treat supple hammer toe.

Fixed hammer toe: A fixed hammer toe cannot be manually straightened out and requires bony resection (28285, Correction, hammertoe [e.g., interphalangeal fusion, partial or total phalangectomy]) or occasionally capsulotomy (28270, Capsulotomy; metatarsophalangeal joint, with or without tenorrhaphy, each joint [separate procedure]) if the MTP joint is hyperextended.

Double Check Payer Injection Rules for Morton’s Neuroma, TTS

Morton’s neuroma (G57.6-, Lesion of plantar nerve…) is a thickening of the plantar nerve at the base of the third and fourth metatarsals. The symptoms usually include pain, tingling, burning and/or numbness. It can be caused by wearing shoes with a narrow toe box or due to sports.

Physicians use physical exam and often x-rays to diagnose a Morton’s neuroma. Usually rest, orthotics, nonsteroidal anti-inflammatory drugs (NSAIDs) and changing shoes will help alleviate the patient’s pain, but corticosteroid injections may be necessary. In some cases, the physician will have to excise the neuroma surgically (28080, Excision, interdigital [Morton] neuroma, single, each).

Compression or entrapment of the posterior tibial nerve causes tarsal tunnel syndrome (G57.5-, Tarsal tunnel syndrome). This condition is similar to carpal tunnel syndrome in the wrist, but this causes pain and numbness at the bottom of the foot. Excessive standing on the feet, varicose veins, bone spurs or athletic injuries, among other causes, can cause tarsal tunnel syndrome.

Physicians use a physical exam to diagnose this condition, usually along with studies including electromyography (95860-95864, Needle electromyography…) or nerve conduction studies (95907-95913, Nerve conduction studies…). Once the physician confirms the diagnosis, she will usually start with conservative treatments such as injections, NSAIDs, rest and alteration of footwear. In some cases, however, the patient may require surgery. The most common treatment is a tarsal tunnel release (28035, Release, tarsal tunnel [posterior tibial nerve decompression]).

Watch out: Insurers may differ on coding regulations for tarsal tunnel and Morton’s neuroma injections. For example, Anthem^® Medicare advises practices to report the procedure codes 64455 (Injection[s], anesthetic agent and/or steroid, plantar common digital nerve[s] [e.g., Morton’s neuroma]) or 64632 (Destruction by neurolytic agent; plantar common digital nerve) for Morton’s Neroma and 28899 (Unlisted procedure, foot or toes) for tarsal tunnel services. Novitas Solutions accepts 64455 for Morton’s Neuroma.

Medicare rules specifically now state that Morton’s neuromas injections do not involve the structures described by CPT^® codes 20550 (Injection[s]; single tendon sheath, or ligament, aponeurosis [e.g., plantar “fascia”]) and 20551 (Injection[s]; single tendon origin/insertion) or direct injection into other peripheral nerves but rather the injection of tissue surrounding a specific focus of inflammation on the foot. These therapies are not to be coded using CPT^® codes 20550, 20551, 64450 (Injection, anesthetic agent; other peripheral nerve or branch), or 64640 (Destruction by neurolytic agent; other peripheral nerve or branch).

Bottom line: Check with your insurer to determine its tarsal tunnel and Morton’s neuroma injection requirements.