Neurology & Pain Management Coding Alert

Question: How do I code acute or chronic lower back pain? Even with the new ICD-10 codes it seems we can only document the pain and not its severity.

Connecticut Subscriber

Answer: As you say, choices for documenting lower back do not specify pain severity. Since October 1 — when ICD-10 2022 took effect — you have three new codes to report the pain: M54.50 (Low back pain, unspecified), M54.51 (Vertebrogenic low back pain), and M54.59 (Other low back pain). However, none of these codes indicate whether the pain is acute or chronic.

If your provider does notate the severity of the lower back pain, you should follow ICD-10 guideline I.C.6.b.1.(b).(i), which says “if the code describes the site of the pain, but does not fully describe whether the pain is acute or chronic,” you may use a code from category G89 “in conjunction with codes that identify the site of pain … if the category G89 code provides additional information.”

For acute lower back pain: Coding will depend on whether your provider has documented the cause of the pain. If it is due to trauma, you will use G89.11 (Acute pain due to trauma); if it is a complication due to a medical procedure, you will use G89.12 (Acute post-thoracotomy pain) if the lower back pain began after a thoracotomy or G89.18 (Other acute postprocedural pain) if it began after another procedure.

If the cause of the pain cannot be determined, you should not use R52 (Pain, unspecified). That’s because the M54.5- codes are now Excludes1 code for R52. So, you should use an M54.5- code for acute lower back pain if the provider does not a determine a cause for the pain.

For chronic lower back pain: In this situation, you have codes for chronic pain caused by trauma, thoracotomy, and other medical procedures (G89.21, G89.22, and G89.28 respectively). You also have two other options: G89.29 (Other chronic pain), which you would use if your provider documented no cause for the chronic lower back pain, and G89.4 (Chronic pain syndrome), which you would use if the chronic pain is “associated with significant psychosocial dysfunction,” as the note to the code suggests.

Expert coding tip 1: ICD-10 does not specify timeframes for acute or chronic pain. Determinations of pain severity are left to provider judgement.

Expert coding tip 2: For code sequencing, follow guideline I.C.6.b.1.(b).(ii), which tells you the G89- code should be sequenced first if “the encounter is for pain control or pain management,” and to assign the code for the specific site of pain first if “the encounter is for any other reason except pain control or pain management, and a related definitive diagnosis has not been established (confirmed) by the provider.”