In recent years, the problem of aging has become more serious all over the world, especially in Japan, which has entered the "super-aging society" since 2010 (1).
Japan, in particular, has been entering the "super-aging society" since 2010 (1). (1) A "super-aging society" is defined as a society in which the population aged 65 or older accounts for more than 21% of the total population, and the current aging rate in Japan is 29.92%. The overall aging rate tends to be higher in developed countries and lower in developing countries. The aging rate is higher in Sweden (20.05%), Germany (22.41%), the United Kingdom (19.17%), and the United States (17.13%), but Japan has the highest aging rate of any of these countries, and measures to address this issue are an urgent priority. It is estimated that the aging rate in Japan will reach about 30% by 2025 and about 40% by 2060. Even nowadays, when you walk around the streets or in hospitals, you get the impression that there are many elderly people, and in another 30 years, there will surely be elderly people everywhere you look.
What kind of problems will occur in terms of physical functions as people get older? For example, the Ministry of Health, Labour and Welfare (MHLW) reports that the number of musculoskeletal disorders requiring orthopedic hospitalization and surgery increases rapidly after the age of 50 (2). The term "locomotor system" refers to the bones, muscles, joints, nerves, and other organs involved in physical movement.
Let's take a more concrete look. According to a survey conducted in 2022, there are more than 4 million disabled people in Japan, 74% of whom are aged 65 or older (3). The most common types of disability are lower limb (hip, knee, and ankle joint) dysfunction, followed by upper limb (shoulder, elbow, and hand joint) dysfunction and generalized motor dysfunction. Dysfunction is defined as the loss of movement in all or any of these joints, or a narrowing of the range of movement. The diseases that cause these dysfunctions are reported as cerebrovascular disorders in 14.4% and osteoarticular diseases in 13.3% of cases(4). Cerebrovascular diseases include cerebral infarction, cerebral hemorrhage, and subarachnoid hemorrhage, in which blood vessels in the brain become clogged (5), and osteoarticular diseases are diseases that affect the skeletal structure, such as back pain (11.6 million people) and osteoarthritis of the knees (12 million people) (6). As people age, the risk of physical disability increases due to these various diseases, making it difficult for them to lead their daily lives on their own.
Conclusion
The aging rate in Japan is the highest among developed countries.
The risk of physical disability increases with age.
Among physical disabilities, motor dysfunction of the lower limbs (hip, knee, and ankle joints) is the most common.
The most common causes of functional disability are stroke, low back pain, and knee osteoarthritis.
1) Cabinet Office, White Paper on Aging Society, 2008 edition.
2) Ministry of Health, Labour and Welfare, Study on the Influence of the Comprehensive Payment System on Medical Economy and Medical Care Delivery System.
3) Ministry of Health, Labour and Welfare, Disability Welfare Division, 25th "Study Team for Revision of Remuneration for Disability Welfare Services".
4) Ministry of Health, Labour and Welfare, Social Support Bureau, Disability Health and Welfare Department, Overview of the Results of the Survey on Children and Persons with Physical Disabilities.
5) Ministry of Health, Labour and Welfare, Health Information Site for Lifestyle-related Diseases
6) Japanese Society of Rehabilitation Medicine, Rehabilitation of Bone and Joint Diseases