ICD-10-CM · Spine

M42.17

M42.17 identifies degenerative osteochondrosis of the intervertebral disc at the lumbosacral junction (L5-S1 level) occurring in adult patients, characterized by disc desiccation, end-plate changes, and loss of disc height at the L5-S1 motion segment.

Verified May 8, 2026 · 5 sources ↓

Status: Billable
Chapter: 13
Related CPT: 14
Region: Spine

Drawn from CDCICD10DataAAPCCMS

Documentation tips

What should appear in the chart to support M42.17.

Source · Editorial brief grounded in 5 cited references ↓

Specify 'lumbosacral' or 'L5-S1' explicitly in the assessment — 'lumbar spine' alone maps to M42.16, not M42.17.
Reference imaging findings that confirm end-plate changes or disc degeneration at L5-S1: MRI Modic classification, disc height loss on X-ray, or CT evidence of end-plate sclerosis.
Document patient age or confirm adult status; the M42.1x subcategory is reserved for adults and must not be used for juvenile/adolescent patients.
If conservative care has been trialed (PT, NSAIDs, injections), document duration and response — this supports medical necessity for advanced imaging or procedural intervention billed alongside M42.17.
When multiple spinal levels are affected, document each region separately so additional M42.1x codes can be assigned — do not lump multi-level disease under a single site code.

Related CPT procedures

Procedure codes commonly billed with M42.17. Linking the right diagnosis to the right procedure is what establishes medical necessity.

Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis

72100 $40.42

Radiologic examination of the lumbosacral spine capturing two or three views, used to evaluate the lumbar vertebrae and sacrum for injury, degeneration, or structural abnormality.

72110 $53.44

Radiologic examination of the lumbar spine (lumbosacral) with a minimum of four views, including oblique and/or bending views.

72148 $191.72

Non-contrast MRI of the lumbar spine used to evaluate disc pathology, spinal stenosis, nerve root compression, and other structural abnormalities without administration of contrast material.

72158 $318.31

MRI of the lumbar spinal canal and its contents performed first without contrast, then repeated after contrast administration for enhanced visualization.

97110 $29.06

Therapeutic exercise billed per 15-minute unit, targeting strength, endurance, range of motion, or flexibility with direct one-on-one patient contact.

97530 $35.07

Dynamic, functional activities that use multiple parameters such as balance, strength, and range of motion together to improve real-world performance, billed in 15-minute units.

99213 $95.19

Established patient office or outpatient visit requiring 20–29 minutes of total time or low-complexity medical decision-making.

99214 $135.61

Office visit for an established patient requiring moderate-complexity medical decision making (MDM), or 30–39 minutes of total provider time on the date of service.

99215 $192.39

Highest-level office or outpatient E/M visit for an established patient, qualifying via high-complexity medical decision making or 40–54 minutes of total provider time on the date of service.

22612 $1,467.64

Posterior or posterolateral lumbar arthrodesis of a single interspace, performed via a posterior approach with bone graft and typically pedicle screw fixation to achieve vertebral segment fusion.

22630 $1,510.72

Posterior interbody arthrodesis of a single lumbar interspace, including laminectomy and/or discectomy performed to prepare the interspace for fusion rather than for decompression.

27279 $758.53

Minimally invasive arthrodesis of the sacroiliac joint using a transfixing implant device placed percutaneously across the joint.

62323 $273.22

Single interlaminar epidural or subarachnoid injection at a lumbar or sacral level, performed under fluoroscopic or CT guidance, delivering a steroid, anesthetic, or other non-neurolytic drug.

64483 $264.87

Transforaminal epidural injection of anesthetic, steroid, or both at one lumbar or sacral level, with fluoroscopic or CT guidance included.

Common coding pitfalls

The recurring mistakes coders make with M42.17 and adjacent codes.

Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓

Coding M42.16 (lumbar) when the provider documented L5-S1 or lumbosacral — those terms map to M42.17, not M42.16.
Using M42.17 for patients under 18; juvenile spinal osteochondrosis belongs under M42.0x (Scheuermann's disease subcategory).
Applying a 7th-character extension to M42.17 — M-codes in Chapter 13 do not use 7th-character encounter designations (A/D/S).
Defaulting to M42.9 (unspecified) when the operative report or MRI clearly identifies lumbosacral pathology — unspecified codes invite payer scrutiny when specific documentation exists.
Failing to add a radiculopathy code (e.g., M54.42 for lumbosacral radiculopathy) when the note documents leg pain, dermatomal symptoms, or nerve root compression findings — M42.17 alone does not capture radicular involvement.

Clinical context

Source · Editorial summary grounded in 5 cited references ↓

M42.17 applies when an adult patient presents with documented osteochondrosis specifically at the lumbosacral region — the junction of the lumbar spine and sacrum, primarily the L5-S1 disc level. This is a degenerative process distinct from juvenile Scheuermann-type osteochondrosis (M42.07); the adult variant involves progressive disc degeneration with Modic end-plate changes, disc space narrowing, and associated lumbosacral pain rather than the vertebral body wedging seen in adolescents. Use M42.17 when the provider has documented the lumbosacral region specifically; if the degeneration spans multiple spinal regions, additional codes for each affected region may be required.

Within the M42.1 adult osteochondrosis subcategory, the sixth character drives regional specificity: .10 = site unspecified, .11 = occiput-C1-C2, .12 = cervical, .13 = cervicothoracic, .14 = thoracic, .15 = thoracolumbar, .16 = lumbar, .17 = lumbosacral, .18 = sacral/sacrococcygeal, .19 = multiple sites. Selecting M42.17 over M42.16 (lumbar) requires explicit documentation placing the pathology at the lumbosacral junction — imaging reports referencing L5-S1 disc degeneration with end-plate involvement are the strongest support.

M42.17 is commonly paired with radiculopathy codes (M54.4x series) when nerve root involvement is documented, or with lumbosacral spondylosis codes if concurrent facet or vertebral body changes are present. It is not an injury code, so no 7th-character extension applies.

Sibling codes

Other billable codes under M42.1 (laterality / anatomic variants).

M42.19

Adult osteochondrosis of spine, multiple sites in spine

M42.13

Adult osteochondrosis of spine, cervicothoracic region

M42.14

Adult osteochondrosis of spine, thoracic region

M42.12

Adult osteochondrosis of spine, cervical region

M42.18

Adult osteochondrosis of spine, sacr/sacrocygl region

M42.15

Adult osteochondrosis of spine, thoracolumbar region

M42.10

Adult osteochondrosis of spine, site unspecified

M42.11

Adult osteochondrosis of spine, occipt-atlan-ax region

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 5 cited references ↓

01What is the difference between M42.16 and M42.17?

M42.16 covers the lumbar region (roughly L1-L4 disc levels); M42.17 is specific to the lumbosacral junction (L5-S1). Use M42.17 when the provider or imaging report explicitly references L5-S1, lumbosacral disc, or lumbosacral junction pathology.

02Can M42.17 be used for a teenager with low back disc changes?

No. M42.17 is under the M42.1 adult osteochondrosis subcategory. Pediatric and adolescent spinal osteochondrosis maps to M42.0x (juvenile osteochondrosis of spine). Confirm patient age and use the correct subcategory.

03Does M42.17 need a 7th-character extension?

No. M42.17 is a Chapter 13 musculoskeletal code and does not use 7th-character extensions. The A/D/S encounter designations apply to injury codes (S-codes), not degenerative spine diagnoses.

04Can I code both M42.17 and a spondylosis code (M47.816) for the same patient?

Yes, if both conditions are documented and clinically distinct. Osteochondrosis (M42.17) targets disc and end-plate degeneration; spondylosis (M47.816) captures facet and vertebral body changes. Sequence based on the primary reason for the encounter.

05What imaging finding best supports M42.17 at claims audit?

MRI with documented Modic end-plate changes at L5-S1, or plain X-ray showing disc space narrowing and end-plate sclerosis at the lumbosacral junction. Reference the specific level and finding in the assessment, not just the radiology impression.

06Should I add a radiculopathy code when the patient has leg pain from L5-S1 disc disease?

Yes. M42.17 does not capture radicular involvement. Add M54.42 (lumbosacral radiculopathy) or M54.4x per documented nerve root level when the note confirms dermatomal symptoms, positive straight-leg raise, or imaging-confirmed nerve root compression.

07What is the ICD-9-CM crosswalk for M42.17?

M42.17 crosswalks to ICD-9-CM 722.73 (Intervertebral disc disorders with myelopathy, lumbar region was not the exact match — the closest historical code was 722.52, degeneration of lumbar or lumbosacral intervertebral disc). Verify with your encoder for payer-specific crosswalk requirements.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

01CDC ICD-10-CM Tabular List 2026 — M42.17
02
stacks.cdc.gov
http://stacks.cdc.gov/view/cdc/250974
03
icd10data.com
https://www.icd10data.com/ICD10CM/Codes/M00-M99/M40-M43/M42-/M42.17
04
aapc.com
https://www.aapc.com/codes/icd-10-codes/M42.17
05
cms.gov
https://www.cms.gov/medicare/coordination-benefits-recovery/overview/icd-code-lists

Mira Scribe

Mira's AI scribe captures region-specific language ('lumbosacral,' 'L5-S1'), imaging grading (Modic type, disc height loss percentage, end-plate sclerosis), and any documented radicular symptoms from the encounter note — ensuring M42.17 is supported over the less-specific M42.16 or M42.9 and preventing a payer downcode or medical necessity denial on advanced imaging or injection claims.

See how Mira captures M42.17 documentation