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.

Ankylosing Spondylitis


Related Terms

  • AS
  • Bamboo Spine
  • Bechterew Syndrome
  • Marie Strümpell Disease
  • Marie Strümpell Spondylitis
  • Rheumatoid Spondylitis
  • Spondyloarthritis
  • Von Bechterew-Strümpell Syndrome

Differential Diagnosis

  • Amyloidosis
  • Cervical disc syndromes
  • Diffuse interstitial heterotopic ossification
  • Forestier's disease (diffuse idiopathic skeletal hyperostosis [DISH])
  • Infective arthritis
  • Osteoarthritis
  • Psoriatic arthritis
  • Reactive arthritis (previously called Reiter's syndrome)
  • Rheumatoid arthritis

Specialists

  • Ophthalmologist
  • Orthopedic (Orthopaedic) Surgeon
  • Physiatrist (Physical Medicine and Rehabilitation Specialist)
  • Rheumatologist

Comorbid Conditions

Factors Influencing Duration

Duration of disease, disease activity, spinal mobility, and peripheral joint involvement are all factors that might influence the length of disability.

Medical Codes

ICD-9-CM:
720.0 - Ankylosing Spondylitis
724.9 - Other Unspecified Back Disorders; Ankylosis of Spine NOS; Compression of Spinal Nerve Root NEC; Spinal Disorder NOS

Overview

© Reed Group
Ankylosing spondylitis (AS) is a chronic, progressive, connective tissue disorder that is characterized by inflammation of the joints of the spine (vertebral joints), hipbones, and sacrum (sacroiliac joints). The condition is one of a group of spondyloarthropathies, including other inflammatory connective tissue disorders such as rheumatoid arthritis, reactive arthritis, psoriatic arthritis, and the arthritis associated with inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis.

Symptoms of ankylosing spondylitis are similar to those of the more common rheumatoid arthritis, including pain, swelling, and stiffness in the affected joints. The difference is that spondylitis primarily affects the spine, forming bony outgrowths (syndesmophytes) between the vertebrae, which may fuse vertebrae and lead to total spinal immobility (ankylosis). Fusion of the vertebrae also can stiffen the rib cage, reducing lung capacity and function. Constitutional symptoms may develop as the condition progresses, including anemia, fatigue, loss of appetite, weight loss, bowel inflammation, and eye inflammation (iritis). The presence and severity of symptoms varies among individuals.

Diagnosis of ankylosing spondylitis is based on clinical features such as presence of low back pain and stiffness for more than 3 months, limited motion in the lumbar spine, and limited chest expansion. AS is termed primary or idiopathic (of unknown origin) if the disease occurs with radiographic evidence of inflammation of the sacrum (sacroiliitis) and without an associated spondyloarthropathy. It is termed secondary if it occurs in conjunction with psoriasis or chronic inflammatory bowel disease.

The onset of ankylosing spondylitis usually occurs between ages 16 and 40. Although a single cause for the condition has not been identified, genetic factors are known to be involved. Human leukocyte antigen B27 (HLA-B27) has been shown to be present in the tissue of a majority of individuals with ankylosing spondylitis, but may be an association and not part of the cause of the disease.

Incidence and Prevalence: Ankylosing spondylitis affects about 1.4% of the general population in the US (Schaffert). Worldwide annual incidence is estimated to be 7.3 per 100,000 individuals; US incidence is reported to be 8.9 per 100,000 individuals age 16 and older (Van der Linden). Prevalence is closely related to the frequency of the HLA-B27 gene (about 8% in the general population). The condition is more prevalent in males than females by about 3 to 1 (Schumacher). It occurs less frequently among people of African and Japanese origin. In the US, it is more prevalent among some Native American tribes and in Central Europe is likely to develop in up to 2% of all HLA-B27 positive adults (Van der Linden).

Source: Medical Disability Advisor



Causation and Known Risk Factors

Individuals who test positive for HLA-B27 and are younger than age 40 are at increased risk for developing ankylosing spondylitis (Van der Linden). From 90% to 95% of individuals with the disorder have the HLA-B27 gene (Schaffert). A family history of the condition also increases risk. Ankylosing spondylitis is 10 to 20 times more common in individuals whose siblings or parents have the disease ("Ankylosing Spondylitis").

Source: Medical Disability Advisor



Diagnosis

History: Individuals typically complain of a gradual onset of low back pain and associated muscle spasms experienced over several months. The pain is usually described as worse in the morning and improving during the day. It may have followed a gradual ascending pattern from the tailbone (sacrum) to the lower back (lumbar spine) to the chest region (thoracic spine) and finally to the neck (cervical spine). Individuals may also report pain and stiffness of the rib cage and/or pain beginning in the larger peripheral joints (e.g., knees, hips, shoulders). Eye pain may be reported as well as a loss of appetite, weight loss, and fatigue. A family history of ankylosing spondylitis may also be reported on questioning.

Physical exam: The exam may reveal tenderness over the area where the sacrum and hipbones meet (sacroiliac joints) and lumbar range of motion may be decreased. Chest expansion may be decreased to well below the 2 inch (5 cm). Evidence of eye inflammation (iritis) may be observed. Peripheral joints will be evaluated for tenderness, swelling, and restricted motion. Limited motion in the lumbar spine means that when the patient bends forward motion occurs by hip flexion, and very little or no lumbar spinal flexion occurs.

Tests: Routine laboratory tests, including complete blood count (CBC) and blood chemistries, may reveal a low-grade anemia, an elevated erythrocyte sedimentation rate (ESR) indicative of active inflammation, and an elevated serum alkaline phosphatase indicating active bone remodeling. Tissue typing (HLA typing) may be done to determine presence of HLA-B27 since AS is more likely if HLA-B27 is positive. X-rays of the pelvis may show characteristic fusion or inflammation of the sacroiliac joints (sacroiliitis). Lumbar x-rays may reveal fusion of the facet joints (anterior and lateral osteophytes bridge disc spaces and fuse motion segments into a "bamboo spine"). MRI will show evidence of inflammation in the sacroiliac joints.

Source: Medical Disability Advisor



Treatment

Treatment goals are to relieve pain and strengthen muscles to promote proper posture. Nonsteroidal anti-inflammatory drugs (NSAIDs) and tumor-necrosis-factor inhibitors are used to reduce pain and inflammation. Use of these medications should allow the individual to participate in exercise programs that improve posture and breathing. Physical therapy helps to maintain range of motion and strength and to teach proper posture and positioning.

Surgical intervention may be necessary for some individuals. Surgical care may include surgical fusion (for stabilization), reduction and stabilization of spinal fractures (which are a potential complication), decompression of cervical or lumbar stenosis (if neurological deficits are present), and possible replacement of weight-bearing joints (e.g., hip). If spontaneous fusion of the spine has occurred in poor position, surgical correction of the spinal deformity by osteotomy of the spine can be done, usually at the cervicothoracic junction or in the lumbar spine.

Exercises to improve posture and breathing can help preserve mobility and limit further disability. Smoking is discouraged because the disorder can eventually limit air exchange.

Source: Medical Disability Advisor



Prognosis

The prognosis is variable but generally favorable, with a tendency for the condition to be self-limiting with either spontaneous remission or a mild course. The disease may also be active over a period of years with life expectancy reduced after 10 years of active disease. The outcome of medical or surgical intervention varies in each individual, although some lessening of symptoms can be expected in all individuals.

Comparatively few individuals will develop severe functional disability. Disability correlates with duration of disease, disease activity, fixed spinal deformity, and spinal mobility. Severe hip involvement also results in greater functional impairment.

Source: Medical Disability Advisor



Rehabilitation

As ankylosing spondylitis is a chronic, progressive inflammatory disorder, during an acute flare up, the goal of rehabilitation is to decrease pain. Thermal modalities can be used to control discomfort, in combination with pharmacological management. Deep breathing exercises may be taught to promote full chest expansion and mobility of the chest cavity.

Once pain has decreased, the therapist may teach postural exercises, emphasizing trunk extension exercises and strengthening of the back extensor muscles. Some individuals may experience inflammation of the tendons where they attach to the bone. This condition can be treated with modalities and gentle range of motion exercises, both of which may control pain and prevent loss of motion commonly associated with the condition (Sweeney).

A general aerobic exercise program is advisable in the form of low impact activities such as biking, swimming, or walking (Analay). The importance of breathing, postural, and aerobic exercises must be emphasized to the individual in therapy. Group therapy seems to yield better results than a home exercise program (Hidding; Van Tubergen).

An occupational therapy evaluation may be useful to promote independence in all activities of daily living, recommending assistive devices. An ergonomic evaluation may be beneficial to suggest modifications that might help maintain the individual's employment status.
Because individuals may experience coping difficulties as a result of exacerbations of this disease, they may need counseling or support group participation.

FREQUENCY OF REHABILITATION VISITS
Nonsurgical
SpecialistAnkylosing Spondylitis
Physical or Occupational TherapistUp to 24 visits within 12 weeks
Ankylosing spondylitis is a progressive condition, with lengthy active and inactive periods. During the active period, physician monitoring is crucial in order to assess the medical and rehabilitative needs of the individual, and may be required every 3 to 4 months. During inactive periods, less medical intervention is needed.
The table above represents a range of the usual acceptable number of visits for uncomplicated cases. It provides a framework based on the duration of tissue healing time and standard clinical practice.

Source: Medical Disability Advisor



Complications

Possible complications of ankylosing spondylitis include heart valve disease (e.g., aortic valve stenosis, aortic regurgitation, mitral valve abnormalities), inflammation of the aorta (aortitis), inflammation of the eyes (e.g., uveitis, iridocyclitis), formation of fibrous tissue in the lungs (pulmonary fibrosis), and bowel and bladder dysfunction. In addition, fractures of the spine can occur even without injury.

Source: Medical Disability Advisor



Ability to Work (Return to Work Considerations)

The stage and severity of the disease will determine the need for modifications in the workplace. For most individuals, early-stage symptoms are manageable, and few, if any, restrictions are required, especially with a job classified as sedentary or light. The individual may need to take a few breaks from prolonged sitting or standing or to practice postural and breathing exercises. If there is significant hip involvement, heavy lifting and prolonged standing or walking may need to be decreased or eliminated. Individuals with this diagnosis are usually not able to perform medium work and are rarely capable of heavy work. Those whose peripheral joints are affected are more likely to miss work or require adjustments in work activity than those with spinal involvement only.

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:

  • Was diagnosis of ankylosing spondylitis confirmed by x-ray or by a rheumatologist?
  • Were only spinal manifestations present? Were rib cage and pulmonary function affected? Were peripheral joints affected?
  • Were constitutional effects present such as fatigue, anemia, weight loss?
  • Were there complications related to the ankylosing spondylitis?
  • Does individual have an underlying condition (e.g., another spondyloarthropathy) that may affect recovery?

Regarding treatment:

  • Did individual follow medication regimen?
  • Was surgery necessary? What procedure(s) were performed? Was procedure effective?
  • If unable to quit smoking, would individual benefit from enrollment in a community program to quit smoking?

Regarding prognosis:

  • Has individual complied with lifestyle modifications and exercise therapy? If not, what can be done to increase compliance?
  • How do symptoms affect individual's ability to function?
  • Can workplace accommodations be implemented that will allow individual to continue in occupational duties?

Source: Medical Disability Advisor



References

Cited

Analay, Y., et al. "The Effectiveness of Intense Group Exercise on Patients with Ankylosing Spondylitis." Clinical Rehabilitation 17 6 (2003): 631-636. National Center for Biotechnology Information. National Library of Medicine. 22 Oct. 2008 <PMID: 12971708>.

Hidding, A., et al. "Is Group Physical Therapy Superior to Individualized Therapy in Ankylosing Spondylitis? A Randomized Controlled Trial." Arthristis Care Res. 6 3 (1993): 117-125. National Center for Biotechnology Information. National Library of Medicine. 22 Oct. 2008 <PMID: 8130287>.

Porter, Robert S., et al., eds. "Ankylosing Spondylitis." The Merck Manuals Online Medical Library. Home ed. Whitehouse Station, N.J.: Merck Research Laboratories, 2008. Merck. Merck & Co., Inc. 29 Dec. 2008 <http://www.merck.com/mmhe/sec05/ch066/ch066c.html#sec05-ch066-ch066a-439>.

Schaffert, Alan. "Ankylosing Spondylitis." eMedicine. Eds. Rodrigo O. Kuljis, et al. 8 Jan. 2007. Medscape. 22 Oct. 2008 <http://emedicine.com/neuro/topic15.htm>.

Sweeney, S., G. Taylor, and A. Calin. "The Effect of a Home Based Exercise Intervention Package on Outcome in Ankylosing Spondylitis: A Randomized Controlled Trial." Journal of Rheumatology 29 4 (2002): 763-766. National Center for Biotechnology Information. National Library of Medicine. 22 Oct. 2008 <PMID: 11950019>.

Van der Linden, S. "Ankylosing Spondylitis." Kelley's Textbook of Rheumatology. Eds. Edward Harris, et al. 7th ed. Philadelphia: Elsevier, Inc., 2005.

Van Tubergen, A., et al. "Cost Effectiveness of Combined Spa-Exercise Therapy in Ankylosing Spondylitis: A Randomized Controlled Trial." Arthritis and Rheumatism 47 5 (2002): 459-467. National Center for Biotechnology Information. National Library of Medicine. 22 Oct. 2008 <PMID: 12382292>.

Source: Medical Disability Advisor






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