This was in response to a comment heard in a gym today.
From: Sir. Paul Edmondson
So, the perception by many in the PT industry is that training, exercising in the Transverse Plane (rotational movement) is dangerous for Low Back (lumbar spine) and Knee structures.
In fact, I was one of the guilty teachers once upon a time conveying the above statement as well.
The reality however is different, if we decide to eliminate the transverse plane, human movement and performance will decline not to mention a huge increase in musculoskeletal injuries.
The consideration comes from the notion that the Lumbar segments do not possess a great deal of rotation avaliability because of their limitations in the facet joint arrangement (1 degree per vertebrae) and the design of the Knee has minimal rotational ability, whilst both these are true considerations we must identify that rotation DOES occur at both sites (albeit minimal).
To date, this message about eliminating rotation because of the above, comes purely from an isolationists viewpoint (topographic anatomy), when in fact we have to consider the synergistic segments above and below both sites in motion with their counterparts.
Whilst my knee diving to the inside is something to be aware of, if my hands and trunk have been driven to the left in, let's say a right foot anterior lunge then my knee coming in is very natural and healthy to slow down the forces entering into my body. Provided their is contribution of the same side foot pronating and hips also turning to the left- then my knee is involved and is a small part of a very healthy Chain Reaction to this particular exercise.
In the same breath, and exercise, if my exercise above with the hands being driven to the left, my left scapula will retract, whilst my right protracts, my thoracic spine rotates to the left faster and further than my lumbar segments (but they do rotate- contrary to popular belief!) and the low back contributes to a full body rotation driven by what my hands are doing whilst lunging forwards.
Both of these structures are slaves to the forces we impose daily to them plus the driving parts of my body "telling these" segments where to go. To sum this up, movement is driven, the bones move in the direction driven, the bones closest to the driver move faster than those situated further away, this sequencing of the bones (moving at differing speeds) allows the myofascial system to decelerate - interestingly if you look at an up to date text book( fascia the tensional network of human body best one springs to mind) then you'll see that ALL muscles and fascia in the body run in 'helical spirals' meaning they contribute and favour rotation in their "turning-on" process- and the joints to be 'fed' motion to help fluids transfer (blood, water, lymph).
Finally, why the body favours rotation movements in ALL functional daily tasks/rigours is because it's the ONLY plane of the 3 that doesn't directly fight gravity, we spiral through it which gives our tissues the unique helical arrangements. Lastly look at the Talus in the foot and how it takes Sagittal gait and converts it into frontal and transverse plane motion for free. A clever design if ever there was one.
Walking, playing golf, throwing a ball......it's all about the transverse plane. Train it as a Chain Reaction approach neglect the link action approach that led to the fallacy in the first place.