Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Job Classification

In most duration tables, five job classifications are displayed. These job classifications are based on the amount of physical effort required to perform the work. The classifications correspond to the Strength Factor classifications described in the United States Department of Labor's Dictionary of Occupational Titles. The following definitions are quoted directly from that publication.

Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Disc Calcification


Related Terms

  • Degenerative Disc Disease
  • Disc Calcium Deposits
  • Intervertebral Chondrocalcinosis

Differential Diagnosis

Specialists

  • Neurosurgeon
  • Orthopedic (Orthopaedic) Surgeon
  • Radiologist
  • Rheumatologist

Comorbid Conditions

  • Congenital spinal anomalies
  • Herniated disc
  • Obesity

Factors Influencing Duration

Disc calcification usually is asymptomatic. If symptoms are present, the length of disability may be influenced by the severity of symptoms and response to treatment. When several discs are calcified, spinal range of motion may be decreased, resulting in stiffness that may be exacerbated by certain activities. The presence of complications may also affect duration.

Medical Codes

ICD-9-CM:
722.9 - Disc Disorder, Other and Unspecified; Disc Calcification
722.90 - Disc Disorder, Other and Unspecified, Unspecified Region
722.91 - Disc Disorder, Other and Unspecified, Cervical Region
722.92 - Disc Disorder, Other and Unspecified, Thoracic Region
722.93 - Disc Disorder, Other and Unspecified, Lumbar Region

Overview

Disc calcification is the deposition of calcium in intervertebral discs. The finding is noted on imaging, at operation, or at autopsy; it frequently is found coincidentally during an examination for another problem. Disc calcification is not a diagnosis or disease, nor is it a likely cause of disability. The condition occurs when the intervertebral discs between the bones of the spine (vertebrae) develop calcium deposits in the gelatin-like center (nucleus pulposus), most commonly in the fibers of the outer ring (annulus fibrosus), or in the cartilage plate near the disc (chondrocalcinosis). It often is associated with a decrease in disc space height (Chanchairujira). The condition is seen most frequently in the thoracolumbar spine. The deposits are a sign of degenerative changes in the structure of the disc and usually cause no symptoms. However, the calcium deposits may enlarge and multiply, eventually creating a rigid, calcified area that can increase pressure within the disc, making it potentially more vulnerable to injury (Natatajan).

Incidence and Prevalence: At autopsy, disc calcification is observed in 80% of individuals, with 8% of cases of disc calcification occurring in the upper thoracic spine, 17% in the middle thoracic spine, and 60% occurring in the lower thoracic spine (Chanchairujira).

Source: Medical Disability Advisor



Causation and Known Risk Factors

Intervertebral disc calcification usually occurs in individuals 60 years of age or older. Disc calcification also may be identified in individuals younger than 20 years of age, but in this group the calcium deposits tend to spontaneously regress (Beluffi).

Individuals with a lateral curvature of the spine (scoliosis) are at increased risk for disc calcification (Roberts), as are those with a condition in which the spine becomes chronically inflamed and eventually fuses (ankylosing spondylitis) (Weisman). Individuals with hyperparathyroidism or those with thalassemia also have a higher risk for disc calcification.

Source: Medical Disability Advisor



Diagnosis

History: Disc calcification usually occurs insidiously without painful symptoms. If there is pain, there is no way to reliably determine if the pain relates to the calcified disc or to adjacent vertebral structures.

Physical exam: There are few findings on the physical exam. Decreased spinal range of motion may be present if calcium deposits are widespread within a disc, if several discs are involved, or if there is an associated loss of disc space height. A complete neurological, vascular, and musculoskeletal exam may be performed to rule out any underlying diseases.

Tests: Radiographic findings of calcification or crystal deposition are the hallmark of this condition, most often identified from plain x-ray exams. Calcification within the disc is usually a marker that degenerative changes at that disc level are old. Often there are no symptoms to go along with the x-ray findings. Further testing is not indicated unless other diseases are suspected.

Source: Medical Disability Advisor



Treatment

Disc calcification is a chronic, degenerative process that usually is asymptomatic. If pain is present, medications to relieve pain and muscle spasm may be used, along with conservative back pain measures, including rest from activities that aggravate the symptoms, ice or heat, and general conditioning activities. Physical therapy is used to decrease pain, increase strength, and improve body mechanics. Surgery rarely is needed, but in cases in which calcification is accompanied by a disc herniation, the disc may need to be removed (discectomy). It is very rare for a calcified disc to cause nerve root impingement.

Failure of back pain to improve with conservative treatment is not necessarily related to disc calcification and may be related to other factors contributing to back pain. Therefore, it is important to rule out other factors that may be causing persistent symptoms.

Source: Medical Disability Advisor



Prognosis

Because this condition generally produces no symptoms, the term "recovery" is usually not applicable. Conservative treatment may be effective in relieving symptoms of unrelated back pain. However, like arthritis, disc calcification is a degenerative process not cured by these treatment modalities.

Source: Medical Disability Advisor



Complications

In general, calcified discs are no more likely to rupture (herniate) than are noncalcified degenerative discs. Rarely, the disc may eventually herniate into the spinal canal, causing pressure on the spinal cord or a nerve root.

Spinal stenosis, infection, fractures, or inflammatory disease occurring at the same time requires additional treatment.

Source: Medical Disability Advisor



Ability to Work (Return to Work Considerations)

Since disc calcification is not a disease, but rather a marker of degenerative processes, restrictions and/or accommodations are determined by the condition causing the individual's pain that led to the imaging studies revealing disc calcification.

During periods of acute symptoms, overhead work, repetitive bending, unassisted carrying and lifting, and prolonged sitting or standing, may need to be restricted or eliminated. Depending on the progression of the disease and response to treatment, permanent reductions in physical workload may be required on an individual basis. Education for proper lifting of heavy objects is also important in the rehabilitation process to prepare the individual for returning to work. Company policy on medication usage should be reviewed to determine if pain medication use is compatible with job safety and function.

Source: Medical Disability Advisor



Failure to Recover

If an individual fails to recover within the expected maximum duration period, the reader may wish to consider the following questions to better understand the specifics of an individual's medical case.

Regarding diagnosis:

  • What symptoms are experienced by the individual and how severe are they? Back stiffness or back pain? Decreased back motion, particularly rotation? Pain upon rotation?
  • Has diagnosis of disc calcification been confirmed by x-ray?
  • Is there associated disc herniation?
  • Are other diagnoses present such as spinal stenosis or nerve root impingement that may contribute to painful symptoms?

Regarding treatment:

  • Does individual require medication to relieve pain?
  • Were symptoms treated with conservative back pain measures?
  • Is individual receiving appropriate supportive care such as physical therapy to decrease pain and increase strength?
  • Is individual using correct body mechanics with activity at work and home?
  • If disc herniation is present, does the disc need to be surgically removed (discectomy)?

Regarding prognosis:

  • Is individual experiencing residual pain or stiffness?
  • What is the impact upon work requirements?
  • Would referral to a chronic pain control program be beneficial?
  • Is individual aware the disc calcification is a chronic, degenerative process and is not cured by treatment?

Source: Medical Disability Advisor



References

Cited

Beluffi, G., P. Fiori, and C. Sileo. "Interveretbral Disc Calcifications in Children." La Radiologia medica 114 3 (2009): 331-341. PubMed. 3 Aug. 2009 <PMID: 19274446>.

Chanchairujira, K., et al. "Intervertebral Disk Calcification of the Spine in an Elderly Population: Radiographic Prevalence, Location, and Distribution and Correlation with Spinal Degeneration." Radiology 230 2 (2004): 499-503. PubMed. <PMID: 14752191>.

Natarjan, R. N. "Relationship Between Disc Injury and Manual Lifting: A Poroelastic Finite Element Model Study." Proceedings of the Institution of Mechanical Engineers. Part H, Journal of Engineering in Medicine 222 2 (2008): 195.

Roberts, S., et al. "History and Pathology of the Human Intervertebral Disc." Journal of Bone and Joint Surgery 88 Suppl 2 (2006): 10-14. PubMed. <PMID: 16595436>.

Weisman, M. H., D. van der Hejde, and J. D. Reveille, eds. "Chapter 14 – Imaging in Ankylosing Spondylitis." Anklyosing Spondylitis and the Spondyloarthropathies. 1st ed. Mosby, Inc., 2006.

Source: Medical Disability Advisor






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