To investigate the effectiveness of proprioceptive neuromuscular facilitation combined with heat therapy as opposed to proprioceptive neuromuscular facilitation with cryotherapy in the treatment of mechanical neck pain caused by hypertonic posterior cervical muscles
Authors:   , Francis Romona 
Published: May 2022

Due to sustained partial neck flexion when operating a computer terminal for prolonged periods and by holding a stooped posture being proposed aetiologies for hypertonic posterior cervical muscles and subsequent mechanical neck pain, subjects for this research study were chosen according to their occupation and had to sit at a desk for more the three hours and less than eight hours a day. The purpose of this study was to investigate the effectiveness of proprioceptive neuromuscular facilitation combined with heat therapy as opposed to proprioceptive neuromuscular facilitation combined with cryotherapy in the treatment of mechanical neck pain caused by hypertonic posterior cervical muscles. This was a comparative, randomised, clinical trial consisting of two groups. Group A received proprioceptive neuromuscular facilitation (PNF) combined with heat therapy as their treatment protocol. Group B received proprioceptive neuromuscular facilitation combined with cryotherapy as their treatment protocol. Each group consisted of thirty people between the ages of 25 and 50 who were randomly allocated to their respective groups. It was hypothesized that the analgesic properties related to cryotherapy would result in the treatment group that received PNF stretching combined with cryotherapy yielding better results in terms of objective clinical findings. It was also hypothesized that the therapeutic effects of heat therapy would result in the treatment group receiving PNF stretching combined with heat therapy would yield better results in terms of subjective clinical findings and it is hypothesized that there is an association between the subjective and objective clinical findings between the cryotherapy and the heat therapy groups. The treatment regimen consisted of each participant receiving three treatments over a period of one week and then a one-week follow-up consultation. Subjective data monitored consisted of the Numerical Pain Rating Scale –101 (NRS-101) and the CMCC Neck Disability index. Objective data was collected using the Cervical Range of Motion goniometer (CROM) and the Algometer. At the end of all treatment protocols, statistical (quantitative) analysis was performed to determine whether one treatment protocol was more effective than the other. The analysis of the data collected showed that for all outcomes measured, either of the two treatments was effective overall. Trends suggested optimum treatments were dependent on the age of the patient. Age groups of 46-50 years old, 41-45 years old and the 31-35 years old responded best and improved the most with heat intervention, while age group of 36-40 years old responded best to the cryotherapy intervention. For the youngest age group of 25-30 years old, it did not make a difference whether they received heat therapy or cryotherapy as an intervention. It would seem that the older the patient the more effective the application of heat therapy as a result of the effect of heat therapy on the collagen and elastin fibers within the muscle and its fascia which allowed for increased and sustained improvement of the majority of the age groups represented in this study. Conversely it would seem that the cryotherapy group had only immediate and unsustained effects in the long term, which suggests that the cryotherapy had only a pain relieving function that allowed for the improvement of patients in the study, which when removed resulted in regression to the initial clinical syndrome severity. Most of the outcomes did not show a statistically significant interaction between time, age group and treatment group. The study was underpowered at the age group level, with only 12 subjects per age group. Further studies with a larger sample size in each of the age groups are needed in order to determine whether age is a definitive factor in one treatment being preferred over the other.