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.

Morton's Neuroma


Related Terms

  • Forefoot Neuroma
  • Interdigital Neuritis
  • Interdigital Neuroma
  • Intermetatarsal Neuroma
  • Morton's Neuralgia
  • Morton’s Metatarsalgia
  • Plantar Neuroma

Differential Diagnosis

Specialists

  • Orthopedic (Orthopaedic) Surgeon

Comorbid Conditions

Factors Influencing Duration

Factors that influence length of disability include type of treatment required and individual response to treatment and recommendations.

Medical Codes

ICD-9-CM:
355.6 - Lesion on Plantar Nerve; Mortons Metatarsalgia, Neuralgia, or Neuroma

Overview

© Reed Group
In its most general sense, the word “neuroma” refers to any swelling of a nerve. Morton's neuroma is a thickening of the fibrous tissue that surrounds one of the sensory digital nerves in the foot, usually the one at the base of the second and third or third and fourth toes. This benign growth may cause swelling, inflammation, pain, numbness, and even permanent loss of sensation (nerve damage) in part of a toe or toes. The condition results from mechanical compression and irritation of the nerve, which may be caused by injury, irritation, or pressure. High-heeled shoes with a narrow toe box can compress the second and third interspaces in the forefoot and, in some individuals, amplify biomechanical stress with walking. Only rarely does a neuroma affect both feet at the same time.

Incidence and Prevalence: Morton’s neuroma is a common problem of the foot (Gonzalez). The mean age of individuals who present with this condition is 45 to 50 years (Thomson).

Source: Medical Disability Advisor



Causation and Known Risk Factors

Women are more likely to develop Morton's neuroma than men, at a ratio of 5:1 (Gonzalez). This may be due in part to wearing high-heeled, narrow-toed shoes, which tend to shift the bones of the feet into an unnatural position. Individuals who engage in running or racquet sports may also have higher rates of Morton's neuroma. Certain deformities such as bunions, hammertoes, or flat feet may predispose an individual to the condition. Overweight individuals are more at risk of developing Morton's neuroma.

Source: Medical Disability Advisor



Diagnosis

History: A typical history includes pain on the ball (plantar area) of the foot during walking or prolonged standing. The pain can be quite severe and incapacitating. Individuals may stop walking, remove their shoes, and rub their feet. The pain may radiate to the toes in some cases and subside after resting. Numbness in the toes may be reported. Episodes of pain are intermittent; two episodes may occur in quick succession, and then none may occur for a year. As the condition progresses, episodes become more frequent.

Physical exam: Swelling, tenderness, calluses, structural abnormalities, muscle weakness, or limited range of motion of the foot may be evident. Pain occurs when pressure is applied to the sides of the foot, compressing the neuroma (Mulder’s sign). There may be numbness in the area between the affected toes.

Tests: History and physical exam are usually sufficient for the diagnosis of Morton’s neuroma. Plain x-rays (radiographs) may reveal bony abnormalities of the adjacent metatarsals or a bone fracture, but are not helpful in diagnosing a neuroma. MRI may be recommended to verify the diagnosis in equivocal cases but is usually not needed. A bone scan may be used to rule out stress fracture and avascular necrosis of a metatarsal head. Tissue biopsy is not necessary for Morton’s neuroma.

Source: Medical Disability Advisor



Treatment

For individuals with mild to moderate discomfort, treatment may consist of reducing forefoot compression by changing to shoes with a lower heel and wider toe box and / or using arch supports (orthotic devices) to relieve pressure. Nonsteroidal anti-inflammatory drugs (NSAIDs) may be prescribed to help with pain. In more severe cases, a local injection of anesthetic may relieve pain temporarily and also predict the likelihood of success with surgery. Corticosteroid injections are also used but have more associated complications. Surgical excision of the neuroma is an option for persistent nerve pain.

Source: Medical Disability Advisor



ACOEM

ACOEM's Practice Guidelines, the gold standard in effective medical treatment of occupational injuries and illnesses, are provided in this section to complement the disability duration guidelines.*
 
Ankle and Foot Disorders
 
* The relationship between the MDGuidelines (MDA) content and ACOEM's guidelines is approximate and does not always link identical diagnoses. The user should consult the diagnostic codes in both guidelines, as well as the clinical descriptions, before assuming an equivalence.

Source: ACOEM Practice Guidelines



Prognosis

An estimated 20% to 30% of individuals with Morton's neuroma will respond to conservative treatment such as using orthotics or changing to shoes with a lower heel and wider toe box. Injection of pain-relieving medication is usually effective for temporary relief. The remaining 70% to 80% of individuals may require surgical excision (Schaller).

Individuals who undergo surgery will have satisfactory results in 75% to 85% of cases (Schaller). However, the neuroma may recur in up to 50% of all individuals following surgery (Gonzalez).

Source: Medical Disability Advisor



Rehabilitation

Treatment strategies for Morton's neuroma range from conservative to surgical intervention. A conservative treatment approach should begin by evaluating sports and work shoes for improper support and narrow toe width. Orthotics may be fitted to help control excessive foot pronation during the heel-strike phase of gait motion. If surgery is necessary, the individual may need to temporarily curtail any aerobic exercise that puts added pressure on the foot. Keeping the foot elevated and using heat and pain relievers may be recommended. A physical therapist may recommend deep tissue massage and stretching exercises to help with scar management and any pain or limited range of motion.

After 2 to 4 weeks, normal shoes should be worn as most daily activities are resumed. If the individual's occupation requires continual standing or constant foot movement, frequent breaks may be necessary. Full recovery is expected after 2 months.

Source: Medical Disability Advisor



Complications

Some individuals with Morton's neuroma develop an abnormal gait due to continuous pain and pressure. Distortion of sensation (dysesthesia) in the foot with the neuroma may also occur. The neuroma and accompanying pain may recur following surgery. Surgery often results in numbness between the toes, but this is usually not a problem for the individual. All surgery carries the risk of bleeding, infection, and nerve damage.

Source: Medical Disability Advisor



Ability to Work (Return to Work Considerations)

Walking and standing may be limited due to pain. If surgery is performed, this limitation may last 3 to 6 weeks postoperatively. The individual may need to wear corrective footwear during recovery. Properly fitting footwear, especially well-padded and low-heeled shoes with a wide toe box, can help prevent recurrence.

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:

  • Does individual wear high-heeled or narrow-toed shoes?
  • Did individual present with severe pain in the ball of the foot?
  • Did physical exam and diagnostic workup rule out other causes of forefoot pain such as arthritis, synovitis, or stress fractures?

Regarding treatment:

  • Has individual been compliant with wearing low-heeled shoes with a wide toe box?
  • Would individual benefit from an orthotic insert?
  • Was an injection of local anesthetic and / or corticosteroids effective in relieving pain? Would further injections be beneficial?
  • Is individual a candidate for surgical removal of neuroma?

Regarding prognosis:

  • Does individual's pain persist despite treatment?
  • Does individual have other conditions, such as obesity, diabetes, and peripheral neuropathy, that may affect recovery and prognosis?
  • Did individual experience any associated complications such as gait abnormalities, recurrence of pain, or altered sensation that could affect prognosis?

Source: Medical Disability Advisor



References

Cited

Gonzalez, Peter, and Richard G. Bowman. "Morton Neuroma." eMedicine. Eds. Robert J. Kaplan, et al. 7 Nov. 2001. Medscape. 13 Jan. 2005 <http://emedicine.com/pmr/topic81.htm>.

Schaller, Thomas, and Patrick L. O'Connor. "Morton Neuroma." eMedicine. Eds. Heidi M. Stephens, et al. 9 May. 2008. Medscape. 5 Jan. 2009 <http://emedicine.com/orthoped/topic623.htm>.

Thomson, C. E., J. N. Gibson, and D. Martin. "Interventions for the Treatment of Morton's Neuroma." Cochrane Database of Systematic Reviews 3 (2004): NA.

General

Frykberg, R. G. "Disorders of the Foot and Ankle." Textbook of Primary Care Medicine. Eds. J. Noble and H. L. Greene. 3rd ed. St. Louis: Mosby-Year Book, Inc., 2001. 1207.

Source: Medical Disability Advisor






Feedback
Send us comments, suggestions, corrections, or anything you would like us to hear. If you are not logged in, you must include your email address, in order for us to respond. We cannot, unfortunately, respond to every comment. If you are seeking medical advice, please contact your physician. Thank you!
Send this comment to:
Sales Customer Support Content Development
 
This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is published with the understanding that the author, editors, and publisher are not engaged in rendering medical, legal, accounting or other professional service. If medical, legal, or other expert assistance is required, the service of a competent professional should be sought. We are unable to respond to requests for advice. Any Sales inquiries should include an email address or other means of communication.