- Author: Scott R Laker, MD; Chief Editor: Consuelo T Lorenzo, MD more...
Overuse injuries, otherwise known as cumulative trauma disorders, are described as tissue damage that results from repetitive demand over the course of time. The term refers to a vast array of diagnoses, including occupational, recreational, and habitual activities.
See Common Pediatric Sports and Recreational Injuries, a Critical Images slideshow, to help recognize some of the more common injuries and conditions associated with pediatric recreational activities.
The pathophysiology of overuse injuries is based on the idea that tissues adapt to the stresses placed on them over time. These stresses include shear, tension, compression, impingement, vibration, and contraction. Mechanical fatigue within tendons, ligaments, neural tissue, and other soft tissues results in characteristic changes depending on their individual properties. This fatigue is theorized to initially lead to adaptations of these tissues. As the tissues attempt to adapt to the demands placed on them, they can incur injury unless they have appropriate time to heal. The rate of injury simply exceeds the rate of adaptation and healing in the tissue. Evidence also suggests that chemical mediators are involved in the initiation and propagation of overuse injuries.
Nerve tissues are at particular risk for ischemic injuries. This ischemia leads to characteristic changes in the nerve itself. The timeline generally begins with subperineurial edema, followed by thickening of the perineurium, thickening of the internal and external epineurium, thinning of the peripheral myelin, and, eventually, axonal degeneration.
One hypothesis is that the development of muscular pain originates from the nearly continuous activation of low-threshold motor units that occurs in muscles performing continuous or slow, repetitive tasks, causing depletion of adenosine 5'-triphosphate (ATP) in those fibers. With insufficient ATP, sarcoplasmic reuptake of Ca++ could be reduced, resulting in high concentrations in the cytosol, allowing Ca++ –dependent activation of phospholipase, the generation of free radicals, and damage to the muscle fibers involved. This theory has a rational physiologic basis, but it remains to be proven. Multiple studies have shown that patients with more significant work-related, upper extremity disorders exhibit more muscular activity on electromyelography (EMG) findings; however, these studies are observational and not designed to exhibit causality.
Increasing data in in vitro and in vivo human and animal models shows that there are tissue-level changes associated with repetitive stress. Prostaglandin E2 has been found to be present in high quantities in overuse tissues in rat and chicken models. This mediator has been suggested to influence cell proliferation, increase collagenase, and decrease collagen synthesis. Increasing loads on these tissues alters the amount of nitric oxide and prostaglandin E2. However, another hypothesis based on rat-model observations suggests that overuse may lead to an understimulation of tendon cells, rather than to overstimulation.
Alterations in the regulation of genes within tendons undergoing overuse have been shown in the rat model. These changes include upregulation of genes associated with cartilage, and down-regulation of genes associated with tendon. This suggests that overuse may cause a morphologic alteration of tendon tissue, causing it to become more cartilaginous.
Moderate (40 N) and high (60 N) cyclic loads are reported to create an acute neuromuscular disorder characterized by delayed hyperexcitability in the lower back. This delay is characteristic of an inflammatory state. Microtears within muscle tissue have been shown to be related to higher repetition loads and cyclic rate.[4, 5, 6, 7]
Psychosocial factors have been implicated in overuse injuries for decades. A partial list includes work satisfaction, perceived physical health, perceived mental health, coping mechanisms of the patient and his/her family, perception of work-readiness, and anxiety.
A review of the English-language literature revealed specific articles focusing on ultrasonographers, equestrian athletes, ballet dancers, bicyclists, baseball players, swimmers, triathletes, golfers, bull riders, martial artists, sign language interpreters, skeletally immature patients, college students, heavy computer users, assembly line workers, tailors (seamstresses), surgeons, dentists, and nurses. This list dramatizes the point that at least the perception exists that many common and some uncommon ailments are associated with repetitive motion.
The Medscape Reference topic Nerve Entrapment Syndromes may also be of interest.
The incidence of overuse injuries as a whole is nearly impossible to estimate given the sheer volume of included diagnoses, as well as the difficulty in establishing clear diagnostic criteria. However, several long-term, retrospective, work-related studies have estimated the annual incidence of upper extremity disorders at 4.5-12.7% per year. The frequency of injury in each diagnostic category is more appropriately left to more focused literature.
A study by Roos et al indicated that compared with high school sports in the United States, the rate of overuse injuries in college sports is 3.28 times greater. The study, which used data from the National Collegiate Athletic Association Injury Surveillance System and the High School Reporting Information Online (High School RIO) sports injury surveillance system, also found that in sex-comparable sports, the rate of overuse injuries was higher in females than in males by ratios of 1.25 (college sports) and 1.55 (high school sports).
A study by Schroeder et al found that in US high school sports, the highest rates of overuse injuries were associated with girls’ track and field and girls’ field hockey. The study, using data from the High School RIO surveillance system, also determined that overuse injuries made up 7.7% of all injuries sustained in high school sports.
Overuse injuries are not associated with direct mortality. Morbidity, however, is significant. The impact of these injuries varies from the occasional annoyance to loss of function as a result of frank tissue destruction. In many performing artists, musicians, craftsmen, and workers, loss of function at even a minor level can result in a significant loss of livelihood (leading to the various difficulties associated with this loss). The direct economic impact of overuse injury in the workplace is immense. The indirect impact is nearly incalculable if the number of health care dollars involved is considered. Of particular note, one interesting review of worker demographic data suggested that workers with cumulative trauma disorders were subjected to employment discrimination. Depression and quality-of-life issues have been described after a diagnosis of chronic overuse injury.
Race is not a differentiating factor for overuse injury incidence.
For a variety of hypothesized reasons, differences in sex play a role in certain overuse injuries. Most notably, a significant female predominance in carpal tunnel syndrome has been noted. This has a variety of possible causes, including anatomical differences in the carpal tunnel, hormonal differences, and, importantly, differences in the activities performed by men and woman. Other biomechanical differences have also been implicated; elbow carrying angles, Q-angles, femoral anteversion, and lean body mass are the most commonly stated. Psychosocial and cultural phenomena also play roles.
Age would be expected to be an independent risk factor for overuse injury; however, given the dependence of overuse injury on activity and the changes in activity that typify aging, the contribution of age as a risk factor is difficult to determine.
Flick J, Devkota A, Tsuzaki M, et al. Cyclic loading alters biomechanical properties and secretion of PGE2 and NO from tendon explants. Clin Biomech (Bristol, Avon). 2006 Jan. 21(1):99-106. [Medline].
Arnoczky SP, Lavagnino M, Egerbacher M. The mechanobiological aetiopathogenesis of tendinopathy: is it the over-stimulation or the under-stimulation of tendon cells?. Int J Exp Pathol. 2007 Aug. 88(4):217-26. [Medline].
Archambault JM, Jelinsky SA, Lake SP, et al. Rat supraspinatus tendon expresses cartilage markers with overuse. J Orthop Res. 2007 May. 25(5):617-24. [Medline].
Devkota AC, Tsuzaki M, Almekinders LC, et al. Distributing a fixed amount of cyclic loading to tendon explants over longer periods induces greater cellular and mechanical responses. J Orthop Res. 2007 Aug. 25(8):1078-86. [Medline].
Le P, Solomonow M, Zhou BH, et al. Cyclic load magnitude is a risk factor for a cumulative lower back disorder. J Occup Environ Med. 2007 Apr. 49(4):375-87. [Medline].
Moore A, Wells R. Effect of cycle time and duty cycle on psychophysically determined acceptable levels in a highly repetitive task. Ergonomics. 2005 Jun 10. 48(7):859-73.
Nakama LH, King KB, Abrahamsson S, et al. Effect of repetition rate on the formation of microtears in tendon in an in vivo cyclical loading model. J Orthop Res. 2007 Sep. 25(9):1176-84. [Medline].
Bongers PM, Kremer AM, ter Laak J. Are psychosocial factors, risk factors for symptoms and signs of the shoulder, elbow, or hand/wrist?: A review of the epidemiological literature. Am J Ind Med. 2002 May. 41(5):315-42. [Medline].
Melhorn JM. Cumulative trauma disorders and repetitive strain injuries. The future. Clin Orthop. 1998 Jun. (351):107-26. [Medline].
Roos KG, Marshall SW, Kerr ZY, et al. Epidemiology of Overuse Injuries in Collegiate and High School Athletics in the United States. Am J Sports Med. 2015 Jul. 43 (7):1790-7. [Medline].
Schroeder AN, Comstock RD, Collins CL, Everhart J, Flanigan D, Best TM. Epidemiology of overuse injuries among high-school athletes in the United States. J Pediatr. 2015 Mar. 166 (3):600-6. [Medline].
Hart DA, Archambault JM, Kydd A, et al. Gender and neurogenic variables in tendon biology and repetitive motion disorders. Clin Orthop. 1998 Jun. (351):44-56. [Medline].
Pritchard MH, Pugh N, Wright I, et al. A vascular basis for repetitive strain injury. Rheumatology (Oxford). 1999 Jul. 38(7):636-9. [Medline].
Battery L, Maffulli N. Inflammation in overuse tendon injuries. Sports Med Arthrosc. 2011 Sep. 19(3):213-7. [Medline].
Clarsen B, Myklebust G, Bahr R. Development and validation of a new method for the registration of overuse injuries in sports injury epidemiology: the Oslo Sports Trauma Research Centre (OSTRC) overuse injury questionnaire. Br J Sports Med. 2013 May. 47(8):495-502. [Medline].
Siewe J, Rudat J, Röllinghoff M, Schlegel UJ, Eysel P, Michael JW. Injuries and overuse syndromes in powerlifting. Int J Sports Med. 2011 Sep. 32(9):703-11. [Medline].
IJmker S, Huysmans MA, Blatter BM, et al. Should office workers spend fewer hours at their computer? A systematic review of the literature. Occup Environ Med. 2007 Apr. 64(4):211-22. [Medline].
Andersen JH, Harhoff M, Grimstrup S, et al. Computer mouse use predicts acute pain but not prolonged or chronic pain in the neck and shoulder. Occup Environ Med. 2008 Feb. 65(2):126-31. [Medline].
Banks KP, Ly JQ, Beall DP, et al. Overuse injuries of the upper extremity in the competitive athlete: magnetic resonance imaging findings associated with repetitive trauma. Curr Probl Diagn Radiol. 2005 Jul-Aug. 34(4):127-42.
Cartwright MS, White DL, Demar S, Wiesler ER, Sarlikiotis T, Chloros GD, et al. Median nerve changes following steroid injection for carpal tunnel syndrome. Muscle Nerve. 2011 Jul. 44(1):25-9. [Medline].
Meltzer KR, Standley PR. Modeled repetitive motion strain and indirect osteopathic manipulative techniques in regulation of human fibroblast proliferation and interleukin secretion. J Am Osteopath Assoc. 2007 Dec. 107(12):527-36. [Medline]. [Full Text].
Hölmich P, Nyvold P, Larsen K. Continued significant effect of physical training as treatment for overuse injury: 8- to 12-year outcome of a randomized clinical trial. Am J Sports Med. 2011 Nov. 39(11):2447-51. [Medline].
Brenner JS,. Overuse injuries, overtraining, and burnout in child and adolescent athletes. Pediatrics. 2007 Jun. 119(6):1242-5. [Medline].
Hreljac A. Etiology, prevention, and early intervention of overuse injuries in runners: a biomechanical perspective. Phys Med Rehabil Clin N Am. 2005 Aug. 16(3):651-67, vi.
Landorf KB. Foot orthoses can reduce lower limb overuse injury rate. J Physiother. 2011. 57(3):193. [Medline].
Ireland DC. Australian repetition strain injury phenomenon. Clin Orthop. 1998 Jun. (351):63-73. [Medline].
MacEachen E. The demise of repetitive strain injury in sceptical governing rationalities of workplace managers. Sociol Health Illn. 2005 May. 27(4):490-514.
Szeto GP, Straker LM, O'Sullivan PB. A comparison of symptomatic and asymptomatic office workers performing monotonous keyboard work--2: neck and shoulder kinematics. Man Ther. 2005 Nov. 10(4):281-91.
Szeto GP, Straker LM, O'Sullivan PB. A comparison of symptomatic and asymptomatic office workers performing monotonous keyboard work--1: neck and shoulder muscle recruitment patterns. Man Ther. 2005 Nov. 10(4):270-80.
Armstrong AJ, McMahon BT, West SL, et al. Workplace discrimination and cumulative trauma disorders: the national EEOC ADA research project. Work. 2005. 25(1):49-56.
Barr AE, Barbe MF, Clark BD. Work-related musculoskeletal disorders of the hand and wrist: epidemiology, pathophysiology, and sensorimotor changes. J Orthop Sports Phys Ther. 2004 Oct. 34(10):610-27. [Medline].
Bonde JP, Mikkelsen S, Andersen JH, et al. Understanding work related musculoskeletal pain: does repetitive work cause stress symptoms?. Occup Environ Med. 2005 Jan. 62(1):41-8. [Medline].
Geraci MC, Brown W. Evidence-based treatment of hip and pelvic injuries in runners. Phys Med Rehabil Clin N Am. 2005 Aug. 16(3):711-47.
Lassen CF, Mikkelsen S, Kryger AI, et al. Elbow and wrist/hand symptoms among 6,943 computer operators: a 1-year follow-up study (the NUDATA study). Am J Ind Med. 2004 Nov. 46(5):521-33.
Lassen CF, Mikkelsen S, Kryger AI, et al. Risk factors for persistent elbow, forearm and hand pain among computer workers. Scand J Work Environ Health. 2005 Apr. 31(2):122-31. [Medline].
Maganaris CN, Narici MV, Reeves ND. In vivo human tendon mechanical properties: effect of resistance training in old age. J Musculoskelet Neuronal Interact. 2004 Jun. 4(2):204-8. [Medline].
Morton JP, Atkinson G, MacLaren DP, et al. Reliability of maximal muscle force and voluntary activation as markers of exercise-induced muscle damage. Eur J Appl Physiol. 2005 Aug. 94(5-6):541-8.
Novak CB. Upper extremity work-related musculoskeletal disorders: a treatment perspective. J Orthop Sports Phys Ther. 2004 Oct. 34(10):628-37. [Medline].
Plastaras CT, Rittenberg JD, Rittenberg KE, et al. Comprehensive functional evaluation of the injured runner. Phys Med Rehabil Clin N Am. 2005 Aug. 16(3):623-49.
Shah SN, Miller BS, Kuhn JE. Chronic exertional compartment syndrome. Am J Orthop. 2004 Jul. 33(7):335-41. [Medline].
Toledo SD, Nadler SF, Norris RN, et al. Sports and performing arts medicine. 5. Issues relating to musicians. Arch Phys Med Rehabil. 2004 Mar. 85(3 Suppl 1):S72-4.
Werner RA, Franzblau A, Gell N, et al. A longitudinal study of industrial and clerical workers: predictors of upper extremity tendonitis. J Occup Rehabil. 2005 Mar. 15(1):37-46. [Medline].
Wilson JJ, Best TM. Common overuse tendon problems: a review and recommendations for treatment. Am Fam Physician. 2005 Sep 1. 72(5):811-8. [Medline].