New review paper on the effects of lead wrist bowing

[dubiousgolfer]

Dr Mann

Is this a typo error here in your article (I've highlighted it below)? Should it say 'increased ulnar deviation of the wrist' ?  The reason being I find it almost biomechanically impossible to flex my lead wrist and radial deviate at the same time. 


Image 1 shows my starting (non-bowed) position. Note that my lead wrist is significantly ulnar deviated, but not in full ulnar deviation (note that a straight line drawn along the radial side of my lower lead forearm is angled more downwards relative to my second metacarpal bone).

Image 2 shows what happens when I bow my lead wrist. It causes the clubshaft to angle backwards in an away-from-the-target direction and also slighly groundward because I am letting my lead wrist become even more ulnar-deviated. Note that the clubface is not closing while the clubshaft is angling backwards. The reason why the clubface is not closing is because i) I am deliberately not twisting the club handle counterclockwise with the 4th and 5th fingers of my lead hand and ii) I am deliberately avoiding any left wrist circumductory roll motion due to the biomechanical combination of increased lead wrist bowing + increased radial deviation of the wrist (which can cause the clubshaft to rotate in a counterclockwise rotary direction).

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Do you think JS and Tyler Ferrell are just making a basic error in their instruction because they do not understand that 'circumduction' closes the clubface ?  That they lack the anatomical expertise to accurately explain the biomechanics required to close the clubface?

DG

[imperfectgolfer]

DG,

You asked-: "Is this a typo error here in your article (I've highlighted it below)? Should it say 'increased ulnar deviation of the wrist' ? The reason being I find it almost biomechanically impossible to flex my lead wrist and radial deviate at the same time."

No - it is not a typo.

If one palmar flexes the lead wrist while it is ulnar-deviated, and if one mainly uses the 4th and 5th fingers to palmar flex the ulnar half of the hand more than the radial half, then it will produce a left wrist circumductory roll motion upwards in a radial direction and that will have a clubface closing effect. That is what produces the twistaway phenomenon's increased degree of clubface closing (as demonstrated by Brian Manzella in the capture images below).





Jeff.

[dubiousgolfer]

I see now - many thanks for the clarification.

DG

[golfballwhackerguy]

Hello,

I’m new to the forum but I’ve been reading for the last 3 or 4 months, and been reading Jeff’s papers for the last 8 or 9 years.. I am in no way as advanced as DG or Jeff. Just a mini tour player/instructor who enjoys technique a bit too much. I majored in electrical engineering so I’m very analytical, and I’m currently a +4 handicap.

Question for Jeff: in the review paper, you deem that at P6.5 for Jon Rahm/Collin Morikawa, the left wrist is bowed and becoming ulnar deviated which leaves the face roughly 30* open to ball target line. You then say that the only ways to square the clubface would be through left humerus/left forearm rotation. But just as you showed in the beginning of the paper, the bowing of the left wrist in a state of ulnar deviation opens the clubface. Correct?

Wouldn’t becoming less flexed with the left wrist, while the left shoulder/left hip rotate and move upwards, move forces more upward from the left hand and start to line the club shaft up? This would create a more in line condition of the club shaft and left arm, and this would remove that backwards angulation and the clubface opening that came with it. Could this in plane rotation play a role in clubface closing? There is obviously still some left forearm supination, and maybe some left humerus rotation, but those surely can’t be the only two ways the clubface can close.

Are these thoughts incorrect?

[imperfectgolfer]

Feb 2, 2021 12:36:07 GMT -5 golfballwhackerguy said:

Hello,

I’m new to the forum but I’ve been reading for the last 3 or 4 months, and been reading Jeff’s papers for the last 8 or 9 years.. I am in no way as advanced as DG or Jeff. Just a mini tour player/instructor who enjoys technique a bit too much. I majored in electrical engineering so I’m very analytical, and I’m currently a +4 handicap.

Question for Jeff: in the review paper, you deem that at P6.5 for Jon Rahm/Collin Morikawa, the left wrist is bowed and becoming ulnar deviated which leaves the face roughly 30* open to ball target line. You then say that the only ways to square the clubface would be through left humerus/left forearm rotation. But just as you showed in the beginning of the paper, the bowing of the left wrist in a state of ulnar deviation opens the clubface. Correct?

Wouldn’t becoming less flexed with the left wrist, while the left shoulder/left hip rotate and move upwards, move forces more upward from the left hand and start to line the club shaft up? This would create a more in line condition of the club shaft and left arm, and this would remove that backwards angulation and the clubface opening that came with it. Could this in plane rotation play a role in clubface closing? There is obviously still some left forearm supination, and maybe some left humerus rotation, but those surely can’t be the only two ways the clubface can close.

Are these thoughts incorrect?

Bowing the lead wrist when the lead wrist is ulnar-deviated does not open the clubface relative to the clubhead arc, but it does open the clubface relative to the ball-target line because the clubshaft angles backwards away from the target. If a golfer causes the lead wrist to become less angled back by allowing his lead wrist to become less bowed in the later downswing, then that would have a clubface closing effect relative to the ball-target line so that less lead forearm supination, and/or lead humerus counterclockwise rotation, would be required to get the clubface square by impact. Jordan Spieth manifests that pattern where his lead wrist is 23 degrees bowed at P6, but only 9 degrees bowed at impact, which means that his lead wrist is becoming less bowed by 14 degrees between P6 => P7, and that "in plane rotation" of the clubshaft means that he will require less lead forearm supination and/or lead humerus counterclockwise rotation between P6 => P7 to get his clubface square by impact (compared to an impact scenario where his lead wrist was still bowed by 23 degrees).

Jeff.

[golfballwhackerguy]

Thank you Jeff. Much appreciated.

[dubiousgolfer]

Dr Mann

Although I understand your previous post explanation (extract below) it might be worthwhile adding it to your article for those readers that do not see the posts on this forum.

"If one palmar flexes the lead wrist while it is ulnar-deviated, and if one mainly uses the 4th and 5th fingers to palmar flex the ulnar half of the hand more than the radial half, then it will produce a left wrist circumductory roll motion upwards in a radial direction and that will have a clubface closing effect. That is what produces the twistaway phenomenon's increased degree of clubface closing (as demonstrated by Brian Manzella in the capture images below)"

The reason it might confuse others is the definition of 'Circumduction' below:

"Circumduction is the movement of the limb, hand, or fingers in a circular pattern, using the sequential combination of flexion, adduction, extension, and abduction motions. Adduction/abduction and circumduction take place at the shoulder, hip, wrist, metacarpophalangeal, and metatarsophalangeal joints."

If I've interpreted the above definition correctly 'adduction' of the wrist is ulnar deviation while abduction is radial deviation, therefore flexion and then ulnar deviation occurs sequentially. Therefore some readers of your article might get confused by bolded point 2 below

Image 2 shows what happens when I bow my lead wrist. It causes the clubshaft to angle backwards in an away-from-the-target direction and also slighly groundward because I am letting my lead wrist become even more ulnar-deviated. Note that the clubface is not closing while the clubshaft is angling backwards. The reason why the clubface is not closing is because i) I am deliberately not twisting the club handle counterclockwise with the 4th and 5th fingers of my lead hand and ii) I am deliberately avoiding any left wrist circumductory roll motion due to the biomechanical combination of increased lead wrist bowing + increased radial deviation of the wrist (which can cause the clubshaft to rotate in a counterclockwise rotary direction).


DG

[imperfectgolfer]

DG,

I do not think that there is any adduction/abduction movement in lead wrist circumduction, and that it only applies to circumductory motions at the shoulder and hip joints.

The phenomenon of circumduction only requires the combination of two movements that are at right angles to each other.

Jeff.

[dubiousgolfer]

Dr Mann

I found the definition of circumduction on the website below:

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courses.lumenlearning.com/austincc-ap1/chapter/types-of-body-movements/#m46398-fs-id1583170

Circumduction

Circumduction is the movement of a body region in a circular manner, in which one end of the body region being moved stays relatively stationary while the other end describes a circle. It involves the sequential combination of flexion, adduction, extension, and abduction at a joint. This type of motion is found at biaxial condyloid and saddle joints, and at multiaxial ball-and-sockets joints (see Figure 9.12e).

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DG

[imperfectgolfer]

DG,

Here is a video showing a circumduction motion of the wrist.





If you want to describe it in terms of being due to a sequential combination of flexion, adduction, extension, and abduction happening at the level of wrist joint, that's OK by me. I prefer to describe it as being due to a sequential combination of flexion, radial deviation, extension and ulnar deviation happening at the level of the wrist joint, and the roll motion can be clockwise or counterclockwise.

Jeff.