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  2. ICD-10-CM Codes List
  3. M00–M99
  4. M40-M43
  5. Kyphosis and lordosis (M40)

Kyphosis and lordosis (M40)

ICD-10 code M40 covers diagnoses related to kyphosis and lordosis, two types of spinal curvature disorders. These codes are specifically used to identify variations and locations of abnormal spinal curvatures in patients, helping healthcare professionals accurately classify these conditions for diagnosis and treatment purposes.

The section includes postural kyphosis (codes like M40.00, M40.03, M40.04), which refers to abnormal outward curvature of the spine commonly known as “kyphosis deformity of spine” or “adolescent postural kyphosis.” Different codes distinguish affected spinal regions such as cervicothoracic or thoracic areas. Other secondary kyphosis (M40.10–M40.15) relates to kyphosis caused by underlying issues like injury or degenerative changes. The category of unspecified or other kyphosis (M40.20–M40.29) covers kyphosis types without clearly defined causes or locations and includes terms like “Dowager's hump” and “neuromuscular kyphosis.” For lordosis, codes beginning with M40.4 and M40.5 address conditions such as “postural lordosis” and unspecified lordosis deformities, sometimes called “hyperlordosis” or “loss of lumbar lordosis.” The ICD-10 code for lordosis helps document deformities related to excessive inward curvature of the lumbar spine. The flatback syndrome (M40.3) is also coded here, describing a loss or flattening of the normal lumbar curve. These distinctions allow medical coders to select the precise ICD-10 code for kyphosis or lordosis based on condition type and spinal region, enabling accurate clinical reporting and billing.

Instructional Notations

Code First

Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.

  • underlying disease

Type 1 Excludes

A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

  • congenital kyphosis and lordosis Q76.4
  • kyphoscoliosis M41
  • postprocedural kyphosis and lordosis M96

Clinical Terms

The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.

Kyphosis

Deformities of the SPINE characterized by an exaggerated convexity of the vertebral column. The forward bending of the thoracic region usually is more than 40 degrees. This deformity sometimes is called round back or hunchback.

Lordosis

The anterior concavity in the curvature of the lumbar and cervical spine as viewed from the side. The term usually refers to abnormally increased curvature (hollow back, saddle back, swayback). It does not include lordosis as normal mating posture in certain animals ( = POSTURE + SEX BEHAVIOR, ANIMAL).

Scheuermann Disease

A type of juvenile osteochondrosis affecting the fibrocartilaginous disc (INTERVERTEBRAL DISC) in the thoracic or thoracolumbar region of the SPINE. It is characterized by a forward concave SPINAL CURVATURE or KYPHOSIS.

Spine

The spinal or vertebral column.