Evaluating Movement
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One of the measurements physical medicine providers use to determine dysfunction and measure progress is range of motion.
There are published references that many providers use to determine what is “normal” for an average patient and if a specific motion cannot make it into that range, it may be dysfunctional or pathologic. While these are generally considered widely accepted values or ranges, is this truly the best fit for everyone and should they be used to set appropriate goals for each patient’s unique body structures and expected movement?
Many times, comparing motion on one side of the body to the other and assessing symmetry of movement may be a better option. A teenage gymnast or dancer will likely have significantly more motion in their joints than what a common reference list will state as “within normal limits (WNL)”. However, how that same person moves on one side of the body should, for all practical purposes be equal to how they move on the other side, even though a restricted movement may still be considered WNL. Any reduced joint range should be corrected as failure to do so will likely lead to early joint degeneration and arthritis.
While certain conditions like surgeries or permanent injuries may make symmetry impossible, we would like to assume that how one joint or region can move on one side of the body, so should it be achievable on the other side.