The Palmaris Longus

Rowden Fullen (2009)

The contact angles of the racket (as distinct from the path of the stroke) are a complex minefield. The good coach of course observes angles at other stages of the stroke even at the end of the follow-through as there are often clues here as to faults and inefficiency. I am solely concerned in this article with the ‘facing’ angle upon the instant of contact with the ball – this controls the lateral (left/right) direction of flight and has much more influence on where the ball ends up rather than the swing itself.

In the case of advanced players some strong FH hitters adopt a slightly trailing approach with the racket held back a little behind the main movement of the hand. This allows the option of trailing on contact or closing on contact with the resultant alteration to the ‘facing’ angle. If this is a controlled adjustment to angle rather than uncontrolled ‘wrist-work’ it is a perfectly legitimate addition to the player’s armoury. The beauty of this is that the ‘catching up’ movement of the racket can be executed with a slow or more rapid movement, even if the arm swing itself is fast, resulting in an increased element of deception.

This ‘catching up’ motion is achieved by flexion of the wrist, by the operation primarily of the flexor carpi radialis and the flexor carpi ulnaris, a further muscle the palmaris longus being an assistant mover in the total movement. This latter muscle is missing in some 2.8 to 24% of individuals, depending on the race and/or ethnic backgrounds; Caucasians have a relatively high prevalence of absence while those of Chinese origin extremely low ; could this be a contributory factor to the success of the Chinese at table tennis?

It would be interesting to know what percentage of the ‘assist’ this particular muscle provides 5, 10 or even 15% and also if there are any recent large scale tests to show in what category of individuals the muscle is absent, for instance male/female statistics. The muscle can be unilaterally or bilaterally absent. Numerous studies seem to indicate that the absence of the PL is more common in women and more often on the left side – also women will tend to be more prone to bilateral agenesis.

It does occur to me that the absence of the palmaris longus may adversely affect if only marginally the development of a good drive player (perhaps in stability and/or touch) and is something which could be picked up relatively early in a player’s career. If we have any surgeons or physiotherapists among our ranks I would be interested in their comments and opinions.

It would also appear that the palmaris longus is a very diverse muscle and can be stronger in some people and even duplicated in others. There is some indication in test results that with a number of racket sports’ players, the tendon development in the wrist area is very pronounced (especially in table tennis where many strokes are produced with use of the wrist rather than the full arm). Does this mean that this muscle can be developed and play a larger part in stroke-play?

It would also be interesting to know if a well developed PL can lead to problems such as ‘Carpal Tunnel’ and ‘Tennis Elbow’. I am interested in any ideas on developing this article or in a follow-up if I receive new information.