Locomotive syndrome

In 2000, the Government of Japan established the insurance system Long-term Care Insurance to resolve the issue of the drastic increase of Japanese elderly people in need of nursing care, which imposed a heavy financial burden on the Japanese society.[3] Locomotive system disorders took up approximately a quarter of the need for long-term nursing care in Japan.[3]

Subsequently, three professional Japanese medical societies, the Japanese Society for Musculoskeletal Medicine, the Japanese Orthopaedic Association, and the Japanese Clinical Orthopaedic Association, put forward the idea of locomotive syndrome in 2007[3] with the aim of enhancing public awareness of locomotive syndrome and calling for plans for its management.[4]

Globally, locomotive syndrome prevalence is estimated to be approximately 10%.[5]

A table depicting the locomotive syndrome prevalence of chronic pain patients of different age groups according to a study in Japan.[6]

Researchers have tried to determine whether there are variations in locomotive syndrome prevalence between sexes. Two surveys in Japan showed that locomotive syndrome prevalence in men was lower than that in women. A 2010 nationwide survey with participation of 4500 subjects in Japan showed the estimated locomotive syndrome prevalence for men and women to be 7.9% and 12.3% respectively.[7] Moreover, another nationwide survey with 5162 subjects in 2014 showed the prevalence for men and women to be 10.8% and 12.9% respectively.[8] Contrarily, a different study in Japan with participation of 963 subjects indicated that the difference in locomotive syndrome prevalence between men and women was not significant.[1]

The prevalence of locomotive syndrome increases as people become older, with the highest in those aged 70 or above at 16%.[2] Locomotive syndrome prevalence in people with chronic pain was eight times higher than that of the general population. In addition, the number of orthopaedic surgery treatments in need of hospitalisation drastically rises after age 50 and reaches a peak after the age of 70.[5]

The main components in the locomotive system include intervertebral disks, joints, bones, nervous and muscular system. The deterioration of locomotive components leads to symptoms such as pain, limitation in joint mobility, malalignment, balance disorder and gait abnormality.[5] Syndrome progression leads to reduced ability to perform activities of daily living independently and eventually results in decreased quality of life and necessity of nursing care. People with locomotive syndrome may not be able to accomplish everyday tasks such as putting socks on while standing on one leg, doing moderately intensive house chores, carrying home 5 pounds of shopping and walking nonstop for 15 minutes.[9] They may also slip around or trip up the house and need to hold on to handrails for support whilst climbing up the stairs.[9]

Degenerative changes in the main components of the locomotive system begin before middle age. Generally in the initial stages, the progression is slow and asymptomatic.[1] The symptoms only become obvious when pathological degeneration changes become advanced.

Locomotive syndrome is generally caused by decreased strength of muscles and balance related to ageing and locomotive conditions such as osteoarthritis, osteoporosis and spondylosis.[10][11][12] Muscle degeneration becomes more common in people aged 50 or above. On average, they lose 3% of their muscle strength annually.[4] This hinders their ability to undertake several physical routine activities. Elderly people with osteoporosis and frailty have a higher risk of hip, vertebra, distal radius and humerus fractures.[10] These fractures can cause pain at the fracture site. For osteoarthritis, which is a medical condition of the synovial joints, the abrasion and breakdown of hyaline cartilage and underlying bone can cause joint pain and thus limit movement.[11] For spondylosis, pressure on the spine wears out the intervertebral discs and disfigures the bone, which causes serious pain and leads to restriction of motion.[12]

Specifically in women, locomotive syndrome may be caused by reduced levels of bone density and physical activity that usually happen after menopause.[4] Bone density level decreases as the level of oestrogen, a hormone essential for healthy bones, drops after menopause.[13] This causes more bone resorption than formation. Additionally, women tend to have smaller bones and lower bone mass than men, which further increases the risk of locomotive syndrome.[9] They may also suffer from insufficient nutrition due to dieting in order to be thin, which further contributes to weak bones.[9]

The diagnosis and assessment of locomotive syndrome are done using the short test battery for locomotive syndrome (STBLS) established by the JOA.[1] STBLS consists of the stand-up test, the two-step test and the 25-question Geriatric Locomotive Function Scale (GLFS-25).[1] Results from STBL serve as a guide to assess the risk, presence and degree of locomotive syndrome. There are two stages of locomotive syndrome. Stage 1 indicates the beginning of mobility function decline and stage 2 indicates a progression of mobility function decline.[1] Individuals with locomotive syndrome are categorised into one of the two stages depending on the scores of the three tests.

Illustration of the stand-up test[1]

Stand-up test

The stand-up test examines and measures the vertical movement ability of the body and the muscle strength of the lower extremities.[3] The test evaluates the ability to stand with one or both legs from stools of heights 10, 20, 30 and 40 cm.[1] The difficulty level increases in order of decreasing stool height and when using one leg instead of two. The test is usually performed in increasing order of difficulty starting from standing up using both legs from a 40 cm high stool. The trial is successful if the individual can stand and hold their position for more than three seconds.[3] The inability to stand up from a 40 cm tall stool using one leg is an indicator of stage 1 locomotive syndrome while the inability to stand up from a 20 cm tall stool using both legs is an indicator of stage 2 locomotive syndrome.[3]

Illustration of the two-step test[1]

Strategies for preventing the onset and progression of locomotive syndrome include regular exercise and appropriate nutritional intake.

As exercise has been proven to significantly improve motor function and limit the decline of functional capacity, habitual exercise is the main method for locomotive syndrome prevention and improvement.[3] The JOA proposed a set of exercises called locomotion training or locotra aimed for the improvement of physical function in the middle-aged and elderly population.[1] Locotra consists of single-leg standing with eyes open, squats, heel raises and front lunges.[3] These exercises help improve balance and muscle strength of the lower extremities which are vital for activities of daily living.[3]

Illustration of single-leg standing exercise[1]

Single-leg standing

Single-leg standing with eyes open is an exercise that effectively improves balance and prevents falls.[1] Individuals are required to raise one foot by 5–10 cm with their eyes open for 1 minute. The exercise is to be done near a stable surface such as a desk to prevent falling. Three repetitions for each leg daily is recommended.[3]

Illustration of squatting exercise[1]