No, for the aforementioned reasons. This is a simplification in order to easily explain the problem. All these affect nerve function. Any physician will tell you that mechanical tension on a nerve can affect its function by either increasing or decreasing its tone. Maybe the displacement is causing other problems and the gas problem is from diet, sucking too much air or simply an inexperienced digestive track.
Most problems are multifactorial.
If there is dysfunction in the body it will be manifested in the musculoskeletal system and the body will benefit by treatment. The idea is to get the body functioning at as high a level as possible by treating out the musculoskeletal dysfunctions and allowing health to manifest. Occasionally the other influences are overwhelming and they need to be dealt with. This is why we are trained as physicians rather than therapists. It is more complex an issue than this.