**10. Leading wrist pronation/supination in the golf swing**

Classical golf teaching used the wrist and hands to generate club head speed at impact. In the back swing the leading wrist pronated turning the back of the leading wrist and forearm to face towards the sky at the top of the backswing. At the top of the back swing the 1st row of carpal bones are held in a pronated position at the top of the swing. During this downswing phase the leading wrist is adjusting back towards a neutral position, with the 1st carpal row of bones traversing from a bowed, pronated position towards supination. The leading wrist rotates towards supination and continues in this motion through impact where the palm of the leading wrist motions to face towards the sky in the follow through phase.

At impact the club head makes contact with the ball and the leading wrist accelerates allowing the leading wrist to unhinge into further supination in a whip-like motion, the right hand frequently rolling over the left hand and wrist thus creating extra club head speed at impact. This move is referred to as "rolling the wrists" at impact.

These pronation and supination motions are not commonly seen in modern golfers. These "handsy" moves are considered to be inconsistent. They are regularly seen in good wind players who need to manipulate the face of the golf club in relation to changing wind directions. The majority of modern elite players and coaches tend to manipulate the radial, ulnar and flexion and extension motions.

#### **11. Elite golfers at the top of the back swing**

There are many versions of the wrist flexion/extension pattern in modern golf swings, ultimately returning the leading wrist to a flexed position at impact. Each technique creates greater swing speeds and allows individual players square the club face at impact. All place varying degrees of stress on the leading wrist. These can be summarised into 3 patterns employed by leading professional golfers [21]**.** All have one thing in common; a flexed wrist at square club face at impact, the body moving at speed providing the acceleration to square the club face.

#### **11.1 Flex and maintain**

John Rahm has a weaker grip or neutral grip at address showing 1 and ½ knuckles in his leading hand. He flexes his wrist at the top of the swing and maintains that *Leading Wrist Injuries in a Golfing Population. Golf Swing Biomechanics a Significant Cause… DOI: http://dx.doi.org/10.5772/intechopen.96979*

flexed position on the down swing and rotates his body to square up the club face at impact.

## **11.2 Flex, flex and rotate**

Dustin Johnson has a stronger grip at address showing 3 knuckles with his wrist held in flexion. At the top of the swing he further flexes his leading wrist. On the way down he turns his body aggressively to square up the club face at impact.

#### **11.3 Extend and flex**

Matt Wolff has a weak to neutral grip at address, extends his wrist at the top of the swing and with great skill and co-ordination rapidly converts his lead wrist to a flexed position on the down swing before he releases the club face into a square position at impact.

Bryson De Chambeau who is considered the longest hitter on the PGA tour has very specific statistics [22].

#### **11.4 Flexion/extension**

13 degree of flexion at address, 11 degrees of extension at the top of the swing and 20 degrees of flexion at impact.

#### **11.5 Ulnar/radial deviation**

20 degrees of ulnar deviation at address, 14 degrees of radial deviation at the top of the swing and 15 degrees of ulnar deviation at impact.
