Selecting the correct ICD-10 code for disc disorders can take a little bit of research. There are many options found in the M50 and M51 categories, which are:
M50- Cervical Disc Disorders
M51- Thoracic, Thoracolumbar, and Lumbosacral Intervertebral Disc Disorders
Each one has the same fourth-character options:
- 0 = disc disorder with myelopathy
- 1 = disc disorder with radiculopathy
- 2 = other disc displacement
- 3 = other disc degeneration
- 4 = Schmorl’s nodes (not available for the cervical region)
- 8 = other disc disorders
- 9 = unspecified disc disorder
The fifth character provides detail about the anatomical location within the spinal region. A basic knowledge of spinal anatomy should make fifth-character selection easy, but only if it is documented properly. This includes transitionary regions. “Cervicothoracic” is clearly designated as C7-T1. Though it is not specifically mentioned, “thoracolumbar” likely only includes T12-L1, and “lumbosacral” probably only refers to the L5-S1 interspace. There is a strange rule for cervical disc disorders indicating that you should code to the most superior level of the disorder. This seems to imply that you would only code M50.11, Cervical disc disorder with radiculopathy, high cervical region, if the problem occurs all throughout the neck. Official sources say that this rule may be clarified someday, so stay tuned.
Unfortunately, some providers might not document with enough specificity to choose the correct codes since they did not have this many options back in the old days of ICD-9. It may help to take a moment and offer up a few definitions for the fourth-character options. It can be helpful to encourage providers to document with the words provided by the code set, but “discdisorders” appears to be a term that includes a broader range of phrases.
“Disc disorders” likely includes protrusions, bulges, and herniation, and this is the term used for the fourth characters “0” or “1.” Disc displacement for the fourth character “2” also could include those conditions, but this character is only for disc disorders that do not include neurological deficits. In other words, if a patient had an MRI report that detailed a disc herniation without neurological complications, the fourth character “2” would be selected even though the word “herniation” does not appear within these code categories. If the same report detailed some neurological issue, the “0” or “1” should be considered for thefourth character.
The “0” is used to indicate myelopathy and the “1” is for radiculopathy. Myelopathy means that there is some sort of neurologic deficit to the spinal cord, whereas radiculopathy means that there is a deficit to nerve roots.
Don’t code radiculitis (M54.1-) separately if you use thefourth character of “1” with radiculopathy for the disc disorders (M50.1- or M51.1-). It is already included in the code. Likewise, don’t code sciatica (M54.3-) if you code for lumbar disc with radiculopathy. It would be redundant. On a side note, lumbar radiculopathy (M54.16) might be used if pain is not yet known to be due a disc, but it radiates from the lumbar spine. The same condition, without confirmation of a disc, might be coded as sciatica(M54.3-) instead if it follows the path of the sciatic nerve down the back of the leg. See for more discussion on the radiculopathy codes found in the M54 category.
Thefourth character or “3” for other disc degeneration is a common X-ray finding, as well as thoracic Schmorl’s nodes (fourth character for M51 codes). It could be suggested that thefourth characters “0,” “1,” or “2” should be accompanied by an MRI report or some way to indicate certainty of the disc disorder. However, “3” or “4” could be confirmed with just an X-ray since they include bony change.
The fourth character “8” for other disc disorders is used only if none of the other fourth-character choices fit. Consider all the others first. The official guidelines indicate that this is how “use other specified” or “NEC” should appear when encountered in a code description. If the patient has a disc disorder that does not match one of the other choices, then this is the proper selection. Read more here.
Only use the fourth character “9” for unspecified disc disorders if the documentation does not indicate anything more than the presence of a disc problem. But beware, payors are expected to ask for clarification if unspecified or “NOS” codes are used.
One more rule to keep in mind is that the symptoms of back or neck pain are included with some of these codes. Don’t code cervicalgia (M54.2) along with cervical disc disorders (M50-), and don’t code low back pain (M54.5) along with lumbar disc displacement (M51.2-). The disc diagnoses are more definitive, and therefore preferable, when establishing medical necessity.
Here is documentation from a sample case that supports the selection of M51.16, lumbar intervertebral disc disorders with radiculopathy:
Subjective: Patient complains of pain and numbness in the right buttock and posterior thigh. It shoots into the thigh when the patient coughs.
Objective: Symptoms are reproduced with right straight leg raiser. Diminished right patellar reflex, muscle strength 4/5 right quadriceps. MRI shows right posterior disc bulge at L4/L5.
These spinal disc codes appear to be a bit complex, but with some study and evaluation, the logic used to create them becomes clear. The provider can use the codes to guide proper documentation and the coder then can select the right codes with confidence.