Straighten out your spinal diagnosis coding

The spine is only one part of the musculoskeletal system, but it is made up of interwoven bones, nerves, and muscles so it is a very complex section. To make matters even more confusing, a single vertebra is more than just a bone; it is a complex segment of anatomical structures.

“It’s important for a coder to understand all of these individual segments of the vertebrae because these details are necessary for accurate coding in both diagnoses and procedures,” says Shelley C. Safian, PhD, MAOM/HSM, CCS-P, CPC-H, CPC-I, CHA, AHIMA-approved ICD-10-CM/PCS trainer of Safian Communications Services in Orlando, FL.

That complexity can make it difficult to accurately assign ICD-9-CM diagnosis codes for the wide range of spinal conditions.

Start with spinal anatomy

Before coders can start assigning diagnosis codes, they need to understand the anatomy of the spine. That spinal anatomy provides the foundation necessary to assign codes both now and after the switch to ICD-10-CM.

The spine is made up of a stack of bones known as vertebrae that run down the posterior of the torso from the brainstem to the tailbone. The spinal column is broken down into five separate areas, based on location from the top of the spine to the bottom:

  • Cervical, C1–C7
  • Thoracic, T1–T12
  • Lumbar, L1–L5
  • Sacral, S1–S5
  • Coccyx, CX

The first cervical vertebra is usually known as C1, but is also called the atlas. C2, the second vertebra down, is also known as the axis. “The good news is these are the only two vertebrae that have alternate names,” says Safian.

The sacral vertebrae, or sacrum, start out as five separate bones at birth and by the time an individual reaches his or her mid-20s, the bones fuse into one bony section. After the bone fuses, the S1–S5 designation refers to the location on the single bone, Safian says.

Similar to the sacrum, the coccyx also starts out as three to five individual bones at birth and fuses into one bone as a person ages.

Each vertebra includes a vertebral body that surrounds the spinal cord to protect it in the front. The spinous process and the pedicle protect the spinal cord in the back.

The pedicles are short stout processes that attach to the superior part of the verterbral body on each side. These extend posteriorly to meet the laminae, which are broad flat plates of bone. They overlap the laminae of the vertebrae below. The articular processes also arise from the junctions of the pedicles and laminae. These bony projections have a small smooth surface known as a facet. Each vertebra includes four articular processes, two upper and two lower that comprise the facet joints.

Coders also need to understand the difference between an interspace and a segment, says Kim Pollock, RN, MBA, CPC, of KarenZupko & Associates, Inc., in Chicago. A vertebral segment represents a single complete vertebral bone with its associated articular processes and laminae.

Although the bones of the vertebral column are stacked one on top of the other, they don’t actually rest on each other. The vertebral interspace is the nonbony compartment between two adjacent vertebral bodies that contains the intervertebral disc, and includes the nucleus pulposus, annulus fibrosus, and two cartilagenous endplates.

“Think of the segment as two bones and the space between,” says Pollock.

Learn congenital spinal conditions

Some congenital conditions affect infants’ spines. Congenital spinal conditions can be divided into three general categories:

  • Malformation, when cells in the spine do not develop normally as the spine is building
  • Disruption, when parts of the spine do not come together correctly
  • Deformation, when parts of the spine form and come together, but not in the proper alignment

One condition that affects babies is hydromyelia (ICD-9-CM code 742.53), which is a dilated central spinal canal. Additional fluid accumulates in the spinal canal, putting pressure on the spinal cord.

Untangle spinal deformities

Deformities of the spine can be caused by anomalous development of the vertebrae in the womb. These conditions can be either simple, meaning the deformity is barely noticeable, or complex, meaning the deformity is very severe and can include cor pulmonale or parapalegia.

The most common spinal congenital deformities include lordosis (code 754.2), kyphosis (code 756.19), and scoliosis (code 754.2). Patients can have many different types of kyphosis or scoliosis. In addition, adults may acquire a form of scoliosis. So when coding a diagnosis of scoliosis, look for documentation indicating whether the condition is congenital or acquired.

Spina bifida (codes 741.xx or 756.17) is another congenital condition. “One of the interesting things about spina bifida is they now have a surgical procedure where they can correct certain versions of spina bifida while the baby is in the womb,” Safian says. When the baby is born, it does not have any signs or manifestations of the condition.

Spina bifida is divided into aperta (code 741.xx) and occulta (code 756.17). In spina bifida aperta, the spinal cord actually projects into the lumbosacral area and the patient has an unclosed segment of the spine.

To correctly code spina bifida aperta, the provider must document the region where the protrusion is located (i.e., cervical, thoracic, or lumbar), Safian says. Coders also need to look for a notation of hydrocephalus. “This is a very common manifestation of spina bifida, but it is not absolute,” Safian says. Not every patient with spina bifida has hydrocephalus, so coders should check whether the physician identifies it because that alters the fourth or fifth digit of the code.

Spina bifida occula is identified by the bony spinal defect. The spinal cord does not protrude so physicians need to perform radiologic studies to diagnosis spina bifida occulta because it is undetectable from the outside.

Determining whether spina bifida is apperta or occulta is important not just for coding an encounter, but also for treatment throughout the life of the patient, Safian says.

Klippel-Feil syndrome (code 756.16) is an abnormal number of cervical vertebrae or fused hemivertebrae. It is classified as type I, II, or III.

Type I is a massive fusion of the cervical spine. It will be visible externally because the individual will have a short, webbed neck and a reduced cervical range of motion. Type II is the fusion of one or two cervical vertebrae, so the signs are less obvious. Type III includes thoracic or lumbar spine anomalies in association with type I or II.

Because ICD-9-CM only includes one code for Klippel-Feil syndrome, the type does not affect code assignment. However, physicians should still be documenting the type. “The more information we can get in those notes now the better off we’ll be,” Safian says. The additional information may eventually be required for ICD-10-CM.

Pick out pathological conditions

Pathological conditions occur when an underlying disease causes a malfunction of the spine or damage to the spine. Pathologic conditions of the spine include:

  • Osteoporosis (code 733.0x)
  • Rheumatoid arthritis of the spine not otherwise specified (code 720.0)
  • Pathologic fracture of the spine (code 733.13)
  • Curvature of the spine (code 737.xx)

Osteoporosis is a metabolic bone disorder that results in a reduction in bone mass. It occurs when the rate of bone reabsorption increases at the same time the rate of bone formation decreases. Because osteoporosis weakens the bone structure, it increases the chance of fracture after a fall.

Don’t be prejudiced in terms of patient age when coding for osteoporosis, Safian says. Elderly patients are more likely to have osteoporosis, but younger individuals can also develop it.

Paget’s disease (code 731.0), also known as osteitis deformans, is a slowly progressing metabolic bone disease. The first phase of the disease is the osteoclastic phase, which is the excessive reabsorption of bone. The second, reactive phase is known as the osteoblastic phase, when abnormal bone function appears to excess. Movement may be impaired and pain becomes persistent and severe. Patients are also at risk for compression fractures that result in kyphosis.

Spondylosis (codes 721.x or 756.11) is a degeneration of the spinal joint that puts pressure on the spinal cord. Coders need to know where the degeneration occurred (i.e., cervical, thoracic, or lumbar) as well as whether it is congenital or acquired as an adult. These factors will completely change your code selection, Safian says.

Spinal stenosis (codes 723.0 or 724.0x depending on whether it occurs in the cervical region) is a narrowing of the nerve cavities, spinal canal, and the intervertebral foramen. Spinal stenosis is usually considered an age-related condition because people over 50 are most often affected, Safian says. However, people who have suffered a previous spinal injury or who have a congenitally narrow spinal canal may seek treatment at a younger age. This condition can cause severe pain, numbness, cramping, and weakness, and can lead to spinal cord myelopathy.

To correctly code spinal stenosis, coders need to know where in the spine it occurs. Because a variety of codes exist, coders must refer to the physician documentation for the specific details, Safian says.

E-mail your questions to Senior Managing Editor Michelle A. Leppert, CPC-A, at


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