How is Aerobic Exercise Compared to Localized Pain Relief Exercises in Patients With Jaw Pain and Neck Pain? Pilot Study

Musculoskeletal (MSK) disorders are some of the most burdensome health issues in the world and the leading causes of years living with a disability.1 Low back pain, neck pain, and other MSK disorders are within the ten more burdensome conditions in the world. Chronic pain, including chronic MSK pain, is increasing in Europe, and almost one in five Europeans have reported having moderate or severe chronic pain, representing approximately 25-35% of the adult population. Thus, MSK pain is considered a major public health problem due to its high prevalence and considerable burden in terms of medical costs, work disability, and reduced quality of life. The most common MSK pain is located in the back and joints, followed by head and neck pain. Temporomandibular disorders (TMD) or commonly known as jaw pain are one of the chronic musculoskeletal disorders (MSKD) that are in close relationship with neck and head pain and are also considered to be a major public health problem as they are the main source of chronic orofacial pain and the most prevalent category of nondental chronic pain conditions in the orofacial region. These disorders affect the masticatory muscles, the temporomandibular joint, and related structures such as the neck and head.

MSK pain is related to poor individuals´ health status and poor quality of life, affecting the patient's family environment. Specifically, there is abundant evidence that has shown the great impact that neck pain and TMD pain have on the subject's quality of life. They interfere with daily activities, diminishing patient's capacity for work and/or ability to interact with their social environment. Across Europe, around 20% of patients with chronic pain have lost their job or have lost their productivity because of pain; this makes the cost of healthcare very high. In addition, neck pain and TMD have been considered to have a great economic impact due to direct care and have been shown to have similar individual impact and burden as back pain (BP) and severe headache. Therefore, chronic pain, especially musculoskeletal pain has been considered a priority in Europe.

Subjects with chronic neck and jaw pain present with persistent pain, allodynia, and hyperalgesia, sometimes extending to regions distant from the neck, head or face, as well as cognitive and motor dysfunction, demonstrating an abnormal function of the central nervous system similar to other chronic painful conditions. In addition, both conditions are commonly related to pain in other anatomical regions and they also might also exhibit a greater risk for pain-associated somatic symptom burden.

Subjects with neck and jaw pain commonly complain of pain in the neck, face and head region. In a population sample with almost 190000 participants, found that subjects with jaw pain presented generally other pains such as headache, low back pain, and neck pain. Neck pain was one of the most common comorbidities in these subjects. The close relationship between jaw and neck pain and dysfunction has been established by several studies. For example, it was concluded that symptoms of the stomatognathic system overlap in patients with TMD and cervical spine disorder (CSD), and symptoms of the cervical spine overlap in the same group of patients (TMD and CSD). Also, it was found that patients with chronic jaw pain more often suffered from cervical spine pain than those without this disorder. It was found that asymptomatic functional disorders of the cervical spine occurred more frequently in patients with internal derangement of the TMJ than in a control group. The presence of tender points in the cervical and shoulder girdle in patients with the same diagnosis was more common, especially in upper segments of the cervical spine, compared with healthy controls. Also, facial pain was associated with reported pain in the neck area and clinical pain resulting from palpation in the muscles of the neck-occiput area.

Furthermore, the literature has highlighted that people with jaw and neck pain have neck muscle impairments relative to healthy people, specifically abnormalities in endurance and performance of the cervical flexor and extensor muscles. People with jaw and neck pain also demonstrate poor performance in the Craniocervical Flexion Test, with the increased electromyographic activity of the superficial cervical flexor muscles. These results implicate the altered endurance capacity of the flexor and extensor cervical muscles that lead to neck-shoulder disturbances observed in people with jaw and neck pain. These physical impairments seem to be a common factor of subjects with neck pain involvement such as cervicogenic headache, and whiplash-associated disorders.