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.

Sprains, Acromioclavicular Joint


Related Terms

  • AC Separation
  • AC Sprain
  • Acromioclavicular Joint Strain
  • Shoulder Separation

Differential Diagnosis

Specialists

  • Hand Surgeon
  • Occupational Therapist
  • Orthopedic (Orthopaedic) Surgeon
  • Physiatrist (Physical Medicine and Rehabilitation Specialist)
  • Physical Therapist
  • Sports Medicine Physician

Comorbid Conditions

Factors Influencing Duration

Dominant versus non-dominant side injury and degree of separation are important factors in determining disability. Returning to work duties that require manual dexterity, lifting, or carrying will require a longer period of recovery. Surgical repair of the injury will increase disability time, especially if work responsibilities require manual dexterity, repetitive use of the joint, or heavy lifting overhead using the affected arm.

Medical Codes

ICD-9-CM:
840.0 - Sprains and Strains of Shoulder and Upper Arm, Acromioclavicular Joint (Ligament)

Overview

The acromioclavicular (AC) joint is an important joint because it is the only true bony attachment of the arm to the rest of the skeleton. The joint is relatively small and normally fairly rigid. Although AC joint injuries, usually described as an AC separation, are often called strains, the term strain is incorrect. A strain occurs when a muscle or tendon becomes overstretched and/or tears. This painful injury is often called a "pulled muscle" and is usually caused by an accident, improper use of a muscle, or overuse of a muscle. A sprain is a stretching or tearing of the tough bands of fibrous tissue that connect one bone to another in the joints (ligaments). Since the AC joint is connected by ligaments, the correct term in sprain. A strain (muscle tear) of the muscles surrounding the AC joint is possible in association of the AC sprain (AC separation).

An acromioclavicular (AC) joint sprain is the result of injury to the ligaments crossing from the collarbone (clavicle) to the acromion, or upper part of the shoulder blade (scapula) (the coracoid process). An AC joint sprain results from excessive or abnormal forces that injure the ligaments without causing a shoulder dislocation or fracture.

A sprain of the ligaments of the AC joint results in varying degrees of looseness (laxity) and deformity of the joint. Sprains are graded based on the severity of ligament damage and resulting separation of the joint. In grade I, or first-degree AC joint sprains, some stretching of ligament fibers has occurred, but without any disruption of the joint. In grade II, or second-degree sprains, the damage is greater, resulting in some fibers being torn and minimal disruption, or displacement, of the joint. Grade III, or third-degree sprains, include a complete disruption (dislocation) of the joint because all the ligament fibers are torn (ruptured). Grade IV through VI sprains are much rarer, are of much greater severity, and are discussed under acromioclavicular dislocations. Sprains of the acromioclavicular joint or strains of the muscles around the AC joint are often incorrectly confused with shoulder (glenohumeral) dislocation.

Source: Medical Disability Advisor



Causation and Known Risk Factors

Acromioclavicular joint sprains occur most often during contact or collision sports (e.g., downhill skiing, rugby, ice hockey, football), but any impact to the top of the shoulder, a fall onto the shoulder, or contact with an object while moving, can result in a AC joint sprain if the force is greater than the ligaments can accommodate. Most often, the force is focused on the tip of the shoulder. Shoulder injuries from falling onto an outstretched hand and arm are more likely to result in a humeral neck fracture or glenohumeral joint dislocation, and a heavy object falling on the shoulder is more likely to result in a fracture. Much less commonly, either injury may result in an AC joint sprain.

Source: Medical Disability Advisor



Diagnosis

History: Individuals usually report a direct blow to the tip of the shoulder, either from a fall (e.g., landing on the side of the shoulder in a football tackle), or from a push or stumble (e.g., being checked into a wall when playing ice hockey). Individuals may complain of pain and weakness, and note a bump on the top of the shoulder. The bump is caused by depression of the scapula relative to the clavicle, and swelling (edema) of the joint itself. Pain may radiate into the base of the neck or down the arm. The individual often carries the arm across the chest, cradling it under the elbow.

Physical exam: Direct visual comparison with the uninjured shoulder reveals an asymmetry of the two joints. The clavicle appears raised on the injured side so that the shoulder appears out of balance. Often abrasions can be observed across and somewhat behind the joint. Moving the shoulder-joint complex reveals weakness of the shoulder, limited active shoulder range of motion, and painful assisted range of motion. Close observation of range of motion and elicited pain helps to distinguish AC joint sprains and shoulder muscle strains from other common shoulder pathologies. The bump or high-riding tip of the clavicle may be repositioned (reduced) into its normal anatomical position by the individual or the doctor, but this maneuver can be painful and the AC separation is often unstable will "pop" back up once the pressure is removed from the top of the AC joint/clavicle.

Tests: X-rays of the AC joint are taken to establish position of the acromion and clavicle and to rule out associated fractures. In rare severe trauma cases, a magnetic resonance imaging (MRI) or computed tomography (CT) scan may be helpful to evaluate damage to the surrounding tissue. Nerve conduction studies are rarely needed. Ultrasound may be used in some cases to further evaluate the shoulder rotator cuff or confirm findings obtained by physical exam or x-ray.

Source: Medical Disability Advisor



Treatment

Grade I injuries are treated with a sling and gradual range of motion and strengthening exercises. Cold therapy and pain medications may be indicated.

Grade II injuries may be treated with a sling or a harness. Use of a special harness that applies pressure to the clavicle to hold it in position while the ligaments heal can be effective, but it is uncomfortable and has fallen out of favor. Careful attention must be paid to the skin under the straps to avoid pressure sores and skin infection. Ice, pain medication, and physical therapy are added when appropriate.

Grade III injuries may be treated with a sling or surgery. Nonsurgical treatment results in a high riding (visible deformity) clavicle and probable long-term osteoarthritis (OA) of the AC joint. Surgical intervention can provide additional stability to the AC joint but does not always result in normal anatomical alignment; multiple surgical procedures have been described. The goal is to try to stabilize the clavicle and/or reduce the AC joint. Open reduction, internal fixation (ORIF) with metal hardware can result in migration of the metal and eventual complications. The bones are realigned, and a metal screw may be inserted, or material such as sutures, synthetic graft material, or wire may be used to hold the joint in position. If a metal screw is used, it may be removed later.

All methods of treatment may require up to 8 to 12 weeks of treatment time. After the sprain is healed, pain in the joint may be treated with corticosteroid injection or RICE.

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.*
 
Shoulder 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

Normal joint function should return after grade I and most grade II injuries in about 8 weeks. Grade III sprains (dislocations) treated surgically require more extensive therapy for improved functional recovery. Aggressive physical therapy often cannot begin until 6 weeks after surgery.

Grade II and III injuries not treated surgically to reduce the dislocation leave the individual with a permanent bump on the tip of the shoulder. Surgery leaves a scar about 2 or 3 inches long depending on the approach.

Source: Medical Disability Advisor



Rehabilitation

Rehabilitation of acromioclavicular joint sprain depends greatly on the severity of the injury. For example, in some cases, individuals may require immobilization in a sling for a short period to control pain (Rizzo), whereas in other cases, individuals may require prolonged use of a sling, in conjunction with supervised exercise.

Individuals with a grade I or II injury may be instructed in range of motion exercises for the hand, wrist, and elbow. Modalities such as ice may be used when necessary to control pain and edema. Once the acute pain is relieved, the individual is instructed in shoulder range of motion and strengthening exercises. Generally painful movements such as horizontal adduction and full passive flexion are avoided initially (Rizzo). The rehabilitation process may warrant the observation and guidance of a physical therapist or occupational therapist until the individual progresses to an independent exercise program.

Individuals with a grade III injury may be managed operatively or nonoperatively (Rizzo). If managed nonoperatively, the individual may be instructed in range of motion exercises for the hand, wrist, and elbow during a period of immobilization. After the initial immobilization period, the individual is instructed in shoulder range of motion exercises and progressed to exercises that strengthen the arm and shoulder (Rizzo). All exercises need to be limited to the pain-free arc of motion. Strengthening exercises progress in intensity as the individual's pain decreases and strength improves. This generally occurs gradually over 6 to 12 weeks (Rizzo). Individuals are instructed in a home program that reflects the exercise regimen prescribed during rehabilitation. If managed operatively, rehabilitation will proceed as described for acromioclavicular dislocation. Rehabilitation protocols are guided by the treating physician. The general focus of rehabilitation is to reduce pain and regain full function of the shoulder girdle.

FREQUENCY OF REHABILITATION VISITS
Nonsurgical
SpecialistSprains, Acromioclavicular Joint
Physical or Occupational TherapistUp to 8 visits within 6 weeks
Surgical
SpecialistSprains, Acromioclavicular Joint
Physical or Occupational TherapistUp to 10 visits within 8 weeks
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

Chronic pain and decreased joint function develop in some individuals, especially those who have degenerative arthritis. Chronic pain from the injury after nonoperative (conservative) treatment may be an indication for removal of the end of the clavicle (excision of the distal clavicle). AC joint arthritis may be treated by a Mumford procedure, in which the distal clavicle is surgically cut (resected) to remove the diseased joint (arthropathy). Care must be taken to avoid removing too much bone or creating additional instability of the AC joint. If the end of the clavicle is damaged, it may need to be removed surgically to reduce the chance of developing arthritis. A small cushion of tissue (meniscus) between the bone ends may be dislodged during the injury and may require surgery to repair or remove. Any fractures around the shoulder area complicate recovery.

Skin abrasions are common with this injury and require careful monitoring during treatment to prevent infection; skin and bursa infections may develop in the area of an abrasion. Careful attention must be given to the skin around the bump to observe stretching (tenting) and tearing. Treatment may be necessary to prevent further damage to the skin and soft tissue around the bump.

Damage to the nerves and vessels in the clavicular area is less likely, but it can occur.

Source: Medical Disability Advisor



Ability to Work (Return to Work Considerations)

Individuals must avoid lifting, carrying, pulling, pushing, or reaching to perform overhead work for 6 to 8 weeks. Individuals prescribed a sling or harness may find their movements and manual dexterity temporarily limited. Individuals may require temporary job reassignment. Company policy on medication usage should be reviewed to determine if pain medication use is compatible with job safety and function.

Risk: Risk for re-injury is dependent on the initial grade of the sprain or strain. See Length of disability above.

Capacity: Capacity is also dependent on the initial grade of the sprain or strain. See Length of disability above.

Tolerance: Tolerance, or level of pain, is linked to the initial grade of the sprain or strain. See Length of disability above. Grade I strains usually resolve in a few days allowing for early return to activities. Grade II strains may be sore for several weeks. Activities will then be limited based on the pain level and tolerance of the individual. Grade III strains requiring surgical repair will have more pain and therefore less tolerance to return to activities.

Accommodations: Accommodations for work tasks are the key to successful earlier return to work.

Source: Medical Disability Advisor



Maximum Medical Improvement

Grade I, 28 to 42 days.
Grade II, 42 to 60 days.
Grade III, non-surgical, 42 to 60 days.
Grade III, surgical, 60 to 180 days depending on the type of surgery.

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 grade of sprain (I, II or III) did the individual sustain?
  • What was mechanism of injury?
  • Does individual complain of pain and weakness?
  • Was a bump detectable on the top of the shoulder?
  • Was individual carrying arm across chest, cradling it under elbow?
  • On visual exam of both shoulders, was asymmetry noted?
  • Did physical exam reveal weakness of forearm, limited active range of motion, and painful assisted range of motion of AC joint?
  • Has individual undergone x-ray of affected area?
  • Was it necessary for individual to undergo MRI, CT, or other imaging? Nerve conduction studies?
  • Have conditions with similar symptoms been ruled out?

Regarding treatment:

  • Is individual's treatment appropriate for grade of injury?
  • Has enough time elapsed for treatment to be effective for the level of sprain diagnosed?
  • Is individual being treated with sling, ice, and pain medication?
  • If individual has been prescribed a sling or harness, is individual using it?
  • Has individual been prescribed physical therapy?
  • Was surgery performed?

Regarding prognosis:

  • Is individual active and compliant in rehabilitation?
  • Does individual engage in a home exercise program?
  • Is individual's employer able to accommodate any necessary restrictions?
  • Does individual have conditions that may affect ability to recover?
  • Does individual have complications such as damage to the end of the clavicle or dislodged meniscus?
  • Did individual develop infection in the skin or bursa?
  • Did individual experience associated damage to nerves or blood vessels?

Source: Medical Disability Advisor



References

Cited

Rizzo, Thomas, et al. "Chapter 9 - Acromioclavicular Injuries." Essentials of Physical Medicine and Rehabilitation. Eds. Walter R. Frontera, Julie K. Silver, and Thomas Rizzo. 2nd ed. Philadelphia: Saunders, Elsevier, 2008.

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.