Neurology & Pain Management Coding Alert

Knowledge of terms helps determine correct diagnosis.

When you’re reporting pain management services for low back pain, there are several factors you need to keep in mind when applying diagnosis codes.

Why? There are several ICD-10 codes that represent low back pain; which one you use will depend on patient specifics and the terminology your provider uses when recording the encounter.

Read on to expand your knowledge of which ICD-10 codes apply to this common condition.

‘Vertebrogenic’ Often Leads to M54.51

“Chronic low back pain frequently stems from the vertebrae itself. Pain that originates at the disc is called discogenic, whereas pain coming from the bone is referred to as vertebrogenic back pain,” according to a post by the Neurosurgery One clinic (www. neurosurgeryone.com/blog/the-overlooked-cause-of-your-chronic-low-back-pain/).

To help coders report patient care to the highest specificity, ICD-10-CM divides M54.5- (Low back pain) into three codes that take this definition into account:

• M54.50 (Low back pain, unspecified)
• M54.51 (Vertebrogenic low back pain)
• M54.59 (Other low back pain)

Code M54.50 includes loin pain and low back pain (lumbago) not otherwise specified (NOS), M54.51 includes low back vertebral endplate pain, and M54.59 applies to specified low back pain that’s not in the vertebrae.

It’s possible, especially at a first encounter, that the exact source of the pain won’t be known, which will likely lead to the unspecified code M54.50. “The correct diagnosis code depends in large part on the extent to which the documentation identifies the site and type of pain,” explains Kent Moore, senior strategist for physician payment at the American Academy of Family Physicians.

Also watch for the following diagnoses listed in an Excludes1 note that applies to all M54.5- codes:

• Low back strain, coded to S39.012- (Strain of muscle, fascia and tendon of lower back)
• Lumbago due to intervertebral disc displacement, coded to M51.2- (Other thoracic, thoracolumbar and lumbosacral intervertebral disc displacement)
• Lumbago with sciatica, coded to M54.4- (Lumbago with sciatica).

“Per the Excludes1 note, some lumbago is classified elsewhere,” Moore points out. Lumbago is a general term often used for pain in the lower back, so you should pay attention to the patient record carefully, and query the provider if questions arise. Additionally, “note that lumbago NOS is the only lumbago coded to M54.50,” says Moore.

Know G89.- Reporting Rules

Adding an unnecessary G89.- (Pain, not elsewhere classified) code to a back pain diagnosis is an easy mistake to make, especially if you aren’t clear about ICD-10-CM Official Guidelines, Section I.C.6.b.1(b)(i), which states, “Codes from category G89 may be used in conjunction with codes that identify the site of pain (including codes from chapter 18 [Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99)]) if the category G89 code provides additional information. For example, if the code describes the site of the pain, but does not fully describe whether the pain is acute or chronic, then both codes [a G89 code and site-specific code] should be assigned.”

Consistent with that guideline, “M54.5- is among a long list of Excludes2 notes under G89.-. That means low back pain is a separate diagnosis from G89.-, and G89.- should not be used for low back pain per se. However, if the patient has both low back pain and pain not elsewhere classified, or if a category G89.- code provides additional information, then codes M54.5- and G89.- may both be used,” says Moore.

Chapter 13 Contains Codes for Chronic/Recurrent Condition

If the patient’s back pain is a result of an injury, code assignment will then be subject to ICD-10-CM guideline I.C.13.b., which states that recurrent bone, joint, or muscle conditions, including those that are the result of a healed injury, are usually found in Chapter 13, Diseases of the musculoskeletal system and connective tissue (M00-M99).

The guideline goes on to state “any current, acute injury should be coded to the appropriate injury code from chapter 19 [Injury, poisoning and certain other consequences of external causes (S00-T88)]. Chronic or recurrent conditions should generally be coded with a code from chapter 13. If it is difficult to determine from the documentation in the record which code is best to describe a condition, query the provider.”

Documentation Leads to Better Coding, Patient Care

“Pain typically falls under acute or chronic,” explains Maureen Leahey, CHC, CPC, primary care coding team leader with Sentara Healthcare in Norfolk, Virginia. “With acute diagnoses, the cause is typically known, such as a car accident. In chronic diagnoses, cause is not always known. It is ongoing and can influence functional or structural changes in the peripheral or central nervous systems,” Leahey says.