Neck and Back Pain and Breathing Pattern Disorders

Introduction:

A dysfunctional breathing pattern is defined as “inappropriate breathing that is persistent enough to cause symptoms with no organic cause” (Bradley and Esformes, 2014). Normal breathing involves synchronised upper rib cage and lower rib cage movement as well as activation of the diaphragm and abdominal muscles. Abnormal breathing, also known as thoracic breathing” instead involves breathing from the upper chest with greater upper rib cage motion compared to lower rib cage. Thoracic breathing is produced by recruiting the accessory muscles of respiration (including upper trapezius, sternocleidomastoid and scalene muscles) rather than abdominal motion. A cross-sectional study by Deshmunk et al (2022) found that 74% of participants complaining of back pain and 68% of those complaining of neck pain presented with a dysfunctional breathing pattern. Individuals with poor posture, scapular dyskinesis, low back pain and neck pain have also been shown to exhibit faulty breathing mechanics, suggesting a link between spinal mechanics and dysfunctional breathing.

There is evidence suggesting a relationship between lower back pain and respiration. The diaphragm is a key driver of the respiratory pump and attaches onto the lower six ribs, xiphoid process and the lumbar vertebral column. Hodges et al (2007) stated that as the diaphragm has an important role in both postural and breathing functions, disruption in one could negatively affect the other. A systematic review (Beeckmans et al, 2016) found a significant correlation between lower back pain and dysfunctional breathing including both pulmonary pathology and non-specific breathing pattern disorders. Furthermore, a case-control study (Roussel et al, 2009) observing patients with chronic lower back pain found significantly more altered breathing patterns during performance of motor testing.

Spinal stability and respiration use similar muscles to function and there is a need for a stabilised cervical and thoracic spine to assist movement of the ribs during inspiration and expiration. Spinal stability is derived from co-contraction of the abdominal muscles which increases the intra-abdominal pressure (Park, Kueon and Hong, 2015). Spinal instability could cause mechanical alterations leading to insufficient respiratory function and the activation of accessory muscles, producing a dysfunctional breathing pattern. A systematic review (Kahlaee, Ghamkhar and Arab, 2017) including 68 studies found a significantly lower maximum inspiration and expiration pressures in patients with chronic neck pain compared to asymptomatic patients. Muscle strength and endurance, cervical range of motion and lower Pco2 were found to be significantly correlated to reduced chest expansion and neck pain. The study concluded breathing re-education to be effective in improving come cervical musculoskeletal impairment and breathing pattern disorders.

Clinically Relevant Anatomy

The thoracic cage is inclusive of the spine, ribs, and the adjacent muscles. The anatomy at this area is important to ensure effective inspiration and expiration in the functional breathing process. Primary inspiratory muscles are the diaphragm and external intercostals, to help elevate the ribs and sternum, with a ‘bucket handle’ rib motion. Expiration is usually a passive process, with additional muscles such as the internal intercostals, and abdominal muscles, making this forceful if required.

The muscles of the diaphragm are directly connected to the spine, via the lower six ribs and their costal cartilage, upper three lumbar vertebrae as right crus, and upper two lumbar vertebrae as left crus, separating the thoracic cavity from the abdominal cavity. The intercostal muscles are located between ribs to aid expansion of the thoracic cage on inspiration.

Accessory muscles aid these original breathing mechanics when additional power is needed to generate larger, deeper breaths. These often include the sternocleidomastoid, scalenes, and trapezius, however any muscle attached to the upper limb and thoracic cage can act as an accessory muscle for inspiration.

Differential diagnoses

Neck pain

Neck Pain without radiculopathy	Neck pain with radiculopathy
Non-specific neck pain	Abscess
Acute disc prolapse	Anterior interosseous nerve entrapment
Acute torticollis	Arteriovenous malformation
Acute trauma (e.g. Whiplash)	Carpal tunnel syndrome
Adverse drug reactions	Cubital tunnel syndrome
Osteoarthritis of the cervical spine	Herpes zoster
Inflammatory arthritis	Parsonage-Turner syndrome (brachial plexopathy)
Cervical strain	Posterior interosseus nerve entrapment
Cervical fracture or dislocation	Radial tunnel syndrome
Cervical radiculopathy	Reflex sympathetic dystrophy
Fibromyalgia	Rotator cuff tendinosis
Infection	Thoracic outlet syndrome
Malignancy
Carotid or vertebral artery dissection
Neurological disorders leading to dystonia
Psychogenic dystonia