INTRODUCTION AND LITERATURE REVIEW
One of the most common musculoskeletal disorders in the general population is neck pain. It is a condition that places a large economic burden on the health care system (Nagrale et al., 2010). Roughly two thirds of the general population have neck pain at some time in their lives (Binder, 2007). Its point prevalence ranges from 6% to 22%, while lifetime prevalence ranges from 14.2% to 71% (Fejer, Kyvik and Hartvigsen, 2006).
Mechanical neck pain is a generalized neck and/or shoulder pain with mechanical characteristics, including symptoms provoked by neck movement, maintained neck postures, or by palpation of the cervical muscles (Fernandez et al., 2007). Its aetiological factors are poorly understood and are usually multifactorial, including poor posture, anxiety and depression, neck strain, occupational injuries, or sporting injuries (Binder, 2007).
Janda (1988) described upper crossed syndrome as facilitation of the upper trapezius, levator scapulae, sternocleidomastoid, and pectoralis muscles, as well as inhibition of the deep cervical flexors, lower trapezius, and serratus anterior. These muscle imbalances and movement dysfunctions may lead to joint degeneration. Joint degeneration may be a direct source of pain, but the actual cause of pain has been often secondary to muscle imbalance (Chaitow, 2008).
Muscle energy technique (MET) is a method of treatment that involves the voluntary contraction of a subject’s muscle(s) in a precisely controlled direction, against a counterforce provided by the operator. MET may be used to decrease pain, stretch tight muscles and fascia, reduce muscle tone, improve local circulation, strengthen weak muscle and mobilise joint restrictions (Fryer and Ruszkowski, 2004). It uses a muscle’s own energy in form of gentle isometric contractions to relax the muscles via autogenic or reciprocal inhibition, and lengthen the muscle (Chaitow, 2008).
1.1 LITERATURE REVIEW
Schenk et al (1994) examined the effects of MET on range of motion for cervical region over a four-week period involving multiple MET sessions. Cervical axial rotation was significantly increased following the treatment period. A systematic review of the effectiveness of manual therapy such as spinal manipulation, mobilization, massage and MET for neck pain demonstrated improvements in both the short and long term on a variety of outcomes. These included pain, functional disability and range of motion outcome measures, and these improvements were evident when combined with exercise (Macaulay, Cameron and Vaughan, 2007). However, a systematic review done by Cochrane on MET for non-specific low-back pain concluded that the review authors could not find adequate evidence to make any definitive judgements about the effectiveness of MET. The quality of the evidence was poor. The available studies were generally too small and reported only short-term outcomes. Most studies were determined to have a high risk of bias because of the way they were designed and conducted, producing unreliable answers about this therapy. At present there is no convincing evidence that MET is effective as a stand-alone therapy or improves the effectiveness as an accompaniment to other therapies (Franke et al., 2015).
A study by Gupta et al. (2008) on effects of post-isometric relaxation versus isometric exercises in nonspecific neck pain concluded that MET showed significant improvement in pain and functional status. Another study done by Abha and Angusamy (2010) who compared post-isometric relaxation with integrated neuromuscular inhibition technique on upper trapezius trigger point concluded that MET is effective in improving pain, and functional status. A study done by Phadke et al. (2016) compared MET with static stretching in patient with mechanical neck pain. The result showed that MET was better than static stretching in improving pain and functional disability in people with mechanical neck pain.
In Muscle Energy Technique Third Edition, the author described long-term effect of MET as a longer duration of treatment with more sessions. One of the example shows that Wallin et al (1985) examined the effect of contract-relax technique (CR), ballistic stretching, and of frequency of stretching on hamstring, ankle plantar flexor and adductor muscle extensibility in 47 subjects. Subjects underwent a stretching program (CR or ballistic stretching) three times a week for 30 days, and then CR once/ twice/ five times a week for the next 30 days. After the 30-day period, those performing CR only once a week maintained their increased flexibility, whereas those that performed CR twice or five times a week gained further significant increases (Chaitow, p.113). There is lack of evidence to allow conclusions to be drawn about the long-term effect of MET for relieving mechanical neck pain. Therefore, this study will be done to determine the long-term effect of MET in reducing pain and functional disability in patients with mechanical neck pain.
1.2 RESEARCH OBJECTIVES OR/ AND HYPOTHESIS
1.2.1 Research Objectives
– To determine the long-term effect of muscle energy technique on pain and functional disability in patients with mechanical neck pain.
– To determine the effect of conventional exercise program on pain and functional disability in patients with mechanical neck pain.
1.2.2 Research Hypothesis
There is significant improvement in long-term effect of muscle energy technique on pain and functional disability in patients with mechanical neck pain.