Epidemiology of musculoskeletal disorders

Musculoskeletal disorders (MSK) are not a "marginal group" of diseases, but one of the very most important causes of contact with healthcare services, sick leave, disability, and societal costs (1-4). They are also one of the most common causes of pain, loss of function, and reduced quality of life (1,5). In Norway, MSK disorders are among the disease groups that account for the largest production losses and a significant part of the disease burden, along with mental disorders, cancer, cardiovascular diseases, and diseases of the nervous system (3,6).

This part of the compendium gives you a detailed, data-driven, and clinically oriented picture of how extensive MSK disorders are, how they are distributed in the population, how they are often coded as symptoms, and what consequences they have for individuals and society.

In 2024, there was a total 17,008,893 general practitioner consultations in Norway (7):

Gender	Number
Women	10 057 759
Men	6 951 134
Total	17 008 893

This illustrates that the general practitioner scheme is the most important arena for contact between the population and the health services. Musculoskeletal disorders constitute a significant portion of these consultations, both as the main reason and as part of complex issues (7.8).

Figures from SSB (2024) show the proportion of the population who had at least one consultation with a general practitioner and emergency services:

• In total, had 72 % of the population had at least one general practitioner consultation during the year.
• 16 % had at least one emergency room contact.

Age group	General practitioner (%)	Emergency room (%)
All ages	72	16
0-5 years	66	29
6-15 years	61	16
16-19 years	72	18
20-29 years	67	17
30-49 years	71	14
50-66 years	77	13
67-79 years	84	16
80-89 years	86	22
90+	67	25

This shows that the general practitioner is clearly the most important entry point to the healthcare system, and that almost all Norwegians have contact with their GP during a year – especially in adulthood and older age. Musculoskeletal complaints are one of the most common reasons for such contacts (1.7).

The diagnosis distribution for GP consultations in 2024 (compressed diagnosis groups) shows:

Diagnosis group	Number	Proportion (%)
Mental illness/disorder	2 160 252	12,7
Respiratory infections	1 557 515	9,2
Local pain/inflammations	1 364 287	8,0
Functional gastrointestinal complaints	689 047	4,1
Back problems	615 364	3,6
High blood pressure	574 024	3,4
Atopy/asthma/allergy/eczema	525 726	3,1
Pregnancy/childbirth/contraception	527 311	3,1
Accidents/injuries	495 383	2,9
Diabetes	468 371	2,8
Other diagnoses	5 303 531	31,2

Important points:

1. Muscle- and skeletal-related diagnoses constitute a significant portion of the consultations (7).
2. Many MSK ailments are hidden in the category “Other diagnoses,” which contains a large proportion of symptom diagnoses (7,10).
3. Mental disorders and MSK ailments are closely related as major diagnosis groups – something that reflects clinical reality: pain and mental health are closely linked.

When the diagnosis groups are combined in a clinically meaningful way, clear gender differences are seen:

Diagnosis groups	Men (%)	Women (%)
Mental health	35	65
Musculoskeletal	35	65
Infections	50	50
Gastrointestinal	35	65
Cardiovascular/metabolic	55	45
Injuries/accidents	60	40
Preventive/administrative contact	40	60

This can be summarized as follows:

• Women dominate in mental disorders, pain, gastrointestinal issues, and preventive contacts.
• Men dominate in cardiovascular disease, diabetes, and injuries.
• Infections are relatively evenly distributed.

For MSK epidemiology, this means that women are more likely than men to visit a general practitioner for pain, back problems, and musculoskeletal complaints. This may be due to biological, social, and cultural factors – including differences in pain perception, health behavior, workload, and gender roles (1,11).

One of the most interesting and clinically important observations is how large a proportion of general practitioner consultations end with a symptom diagnosis, not a specific disease diagnosis (10,12).

Typical symptom diagnoses:

• Local pain/inflammations
• Back problems
• General pain/muscle complaints
• Functional gastrointestinal complaints
• Fear of illness
• Unspecific complaints

Based on Statistics Norway figures:

• Local pain/inflammations: 1,364,287
• Back problems: 615,364
• General pain/muscle complaints: 212,221
• Functional gastrointestinal complaints: 689,047
• Fear of illness: 88,171

In addition, a large proportion of symptom codes fall into the category “Other diagnoses” (5,303,531 consultations).

A conservative estimate (only obvious symptom diagnoses) gives approximately. 17,5 % of the consultations. When including symptom diagnoses in “Other diagnoses”, it reaches about. 48,7 % – that is, around. half of all general practitioner consultations. ends with a symptom diagnosis.

This corresponds with international figures: a Dutch study showed that. 58 % of patients who contact their general practitioner receive at least one symptom diagnosis, and 16% had persistent symptom diagnoses (> 1 year). Symptom diagnoses were more common in women (64%) than men (57%) (12).

For you as a doctor, this means:

• Symptom diagnoses are not the exception – they are the norm.
• Many patients have complaints that cannot be placed in a specific disease category.
• Musculoskeletal complaints are often precisely such symptom-based conditions (back pain, neck pain, shoulder pain, diffuse muscle complaints).
• Good management of symptom diagnoses requires confidence, communication, mastery focus, and the ability to tolerate uncertainty – not just 'finding the error'.

Medically certified sickness absence with diagnoses of the type symptoms and complaints is increasing, while sickness absence with more 'classic' disease diagnoses is decreasing (4,13). This is particularly true in:

• mental disorders
• musculoskeletal disorders
• pregnancy-related complaints

Possible explanations (13):

• Actual changes in which health problems cause sick leave.
• Increased caution in diagnosis – doctors choose symptom diagnoses rather than “heavy” disease diagnoses.
• Increased awareness that many complaints are complex and do not fit into a single disease category.

However, an unclear, subjective diagnosis may have limited usefulness for follow-up and measures, and does not give a good picture of the real reasons why people cannot work. For the MSK field, this means that we must be aware of:

• how we code
• how we communicate
• how we connect diagnosis, function, and measures together

Musculoskeletal diseases are:

• it the most common cause of sick leave in Norway (4)
• cause of approx. 30 % of the sick leave cases (4)
• the second most common cause of disability (after mental disorders) (5)
• responsible for approx. 20 % of the non-fatal health loss (DALYs – disability-adjusted life years) (6)

MSK disorders rarely kill, but they (1,6):

• reduce function
• reduce work capacity
• reduce quality of life

A “musculoskeletal account” for Norway shows:

• 75 % experience pain or complaints from the musculoskeletal system during their lifetime
• 30 % report chronic musculoskeletal complaints in the past year
• Women are more affected than men
• MSD disorders account for about 34 % of all sick leave
• They account for about 30 % of those who become disabled
• They lead to large public expenses (1,4,5,6)

This is not “just a little back pain” – it is one of the largest drivers of sick leave, disability, and health loss.

Occupations with high sick leave (> 14 days) and a large proportion of MSD-related sick leave include:

• Cleaners
• Care and nursing workers
• Construction and civil engineering (9,14)

Typical risk factors (9,14):

• monotonous and repetitive tasks
• work above shoulder height
• work in a squatting or kneeling position
• work in a standing position
• awkward lifting
• workplace injuries

The average sick leave for all employed persons is 5.4%, but in these professions it is significantly higher.

A report from 2019 estimated the annual costs of musculoskeletal disorders in Norway to approximately 255 billion kroner (2016 figures) (15).

This included:

Production loss – 71 billion

• 39% of doctor-certified sick leave
• 28% of disability benefit recipients

Healthcare costs – 18 billion

• hospital stays
• imaging diagnostics
• rehabilitation
• general practitioner consultations
• physiotherapy and chiropractor
• assistive devices
• medications

Disease burden – 167 billion

• pain
• reduced activity and mobility
• shortened life
• reduced quality of life

The Norwegian Institute of Public Health estimated the health loss due to MSK diseases to over 135,000 lost healthy life years in 2016 (6).

The Directorate of Health's report on health-related societal costs (2019–2021) shows the distribution of these costs as follows:

• Burden of disease constitutes 55–60%
• Productivity loss constitutes 20–25%
• Healthcare service costs constitute 19–20% (3)

Five disease groups account for 64% of all costs:

• mental disorders
• Cancer
• Musculoskeletal disorders
• cardiovascular diseases
• diseases of the nervous system (3)

MSK disorders and mental disorders are the largest drivers of productivity loss.

A national registry study (2014–2017) showed:

• about 1/3 of the population consulted health services annually for MSK
• 26% were treated in primary health care
• 7% in specialist healthcare services (16)
• back pain was the most common diagnosis (16)

Over 90% visited a general practitioner first.

Patients who visited a physiotherapist first had a lower likelihood of ending up in specialist healthcare.

A recent study (2024) showed that:

• a small proportion of patients accounted for 61% of all costs
• 94% of the costs were related to hospital treatment
• less than half received conservative treatment before hospital (17)

You must:

• handle nonspecific complaints
• understand that MSK complaints are complex
• think function and coping
• see MSK from a systems perspective
• use conservative treatment early (1,7,16)

1. MSK disorders are extremely common
2. They are one of the main causes of sick leave and disability
3. They account for enormous societal costs
4. Women are more affected than men
5. Symptom diagnoses are common
6. Work environment is an important factor
7. Aging will increase the incidence
8. Good MSK treatment requires focus on function, security, and coping

1. Norwegian Institute of Public Health (FHI). Musculoskeletal disorders – facts and prevalence. Oslo: FHI; 2023.
2. Woolf AD, Pfleger B. Burden of major musculoskeletal conditions. Bull World Health Organ. 2003;81(9):646–56.
3. The Norwegian Directorate of Health. Health-related social costs 2019–2021. Oslo: The Norwegian Directorate of Health; 2024.
4. NAV. Sickness absence statistics – diagnosis distribution. Oslo: NAV; 2023.
5. NAV. Disability statistics – causes of disability. Oslo: NAV; 2023.
6. Global Burden of Disease Study (GBD). Global, regional, and national burden of musculoskeletal disorders. Lancet. 2020.
7. The Norwegian Directorate of Health. Activity data for the general practitioner scheme 2024. Oslo: The Norwegian Directorate of Health; 2024.
8. The Norwegian Directorate of Health. Use of health services for musculoskeletal disorders. Oslo: Norwegian Directorate of Health; 2021.
9. Statistics Norway (SSB). Use of general practitioner and emergency room 2024. Oslo: SSB; 2024.
10. The Norwegian Directorate of Health. Diagnosis distribution in primary health care 2024. Oslo: The Norwegian Directorate of Health; 2024.
11. STAMI – The National Institute of Occupational Health. Fact Book on Work Environment and Health 2023. Oslo: STAMI; 2023.
12. Olde Hartman TC, et al. Symptom diagnoses in primary care: prevalence, persistence and sex differences. Fam Pract. 2013;30(3):269–75.
13. Brage S, Ihlebæk C, Natvig B. Musculoskeletal disorders as causes of sick leave and disability pension. Tidsskr Nor Legeforen. 2010;130:2369–73.
14. STAMI. Work-related musculoskeletal disorders – mechanical and organizational exposures. Oslo: STAMI; 2022.
15. The Norwegian Directorate of Health. Costs of musculoskeletal disorders in Norway. Oslo: Norwegian Directorate of Health; 2019.
16. National registry study 2014–2017. Health care use for musculoskeletal disorders. Mentioned in the Norwegian Directorate of Health analyses 2021.
17. National registry study 2024. Cost distribution for MSK disorders. Mentioned in the Norwegian Directorate of Health's reports 2024.