Phrenic Nerve Impingement and Effect of Superficial Neck Flexors Stretching in Improving Diaphragmatic Function among Patient with Chronic Neck Pain

Abstract

Background: The phrenic nerve is formed on the lateral border of scalenus anterior. It runs vertically downward on the anterior surface of the scalenus anterior. The muscle is oblique and nerve cross it obliquely from its lateral to medial border. In this part the nerve is related anteriorly sternocleidomastoid. The decline in the diaphragm function can occur due to phrenic nerve block but to the best of our search, there is dearth of literature pertaining to involvement of phrenic nerve in patient with chronic neck pain secondary to superficial neck flexors tightness. So, evaluation of these muscle for tightness may be considered which may affect the maximum inspiratory pressure (MIP). Objective: To find the change in diaphragmatic function secondary to phrenic nerve impingement measured through maximum inspiratory pressure (MIP) following stretching of superficial neck flexors in patient with chronic neck pain Methods: An experimental (pre-post design) study involving 40 subjects with mean (±SD) age 22.4 ± 2.8 years was performed. Using purposive sampling 40 subjects (77.5% female and 22.5% male) were used to check phrenic nerve impingement by looking at the effect of superficial neck flexors stretching (sternocleidomastoid and anterior scalene) in improving diaphragmatic function in patient with chronic neck pain. The included subject’s diaphragmatic function was measured through maximum inspiratory pressure using a device capsule sensing pressure gauge followed by stretching of superficial neck flexors on both sides. After two minutes of stretching diaphragmatic function was again measured. Results: There was increase in diaphragmatic function following stretching of superficial neck flexors by 13.2cm H2O which was found to be highly significant statistically with p value < 0.01 Conclusion: The result of present study concluded that superficial neck flexors stretching was effective in treating the impingement of phrenic nerve as measured through maximum inspiratory pressure in patients with chronic neck pain.