LETTERS
"Gamekeeper’s Thumb" Sirs I wish to thank Dr. McCue for his very interesting and knowledgeable discussion of our paper, Treatment of &dquo;Gamekeeper’s Thumb&dquo; in Hockey Players (J Sports Med, Vol. 3, No. 4, July-Aug 1975). We agree with all of his comments; and especially in his statement that m complete tears, surgical reconstruction is indicated and necessary. All the players in our series have had only partial tears of the ligaments. It was for this reason that they regamed normal pinch strength after their period of immobilization.I am sure that sooner or later we will see a complete tear which will result m residual instability after the usual period of conservative therapy. We certamly agree that surgical reconstruction would be indicated in that situation. GEORGE D. ROVFRE, M.D. Assistant Professor Section of Orthopedic Surgery The Bowman Gray School of Medicine
Winston-Salem, North Carolina
Etiology
of tennis elbow
The following comments of Dr. Robert P. Nirschl are in reply to Dr. Bernhaug’s letter an Tennis Elbow which appeared in The Journal of Sports Medicine, Vol. 3, No. 4,1975 Sirs: I suggest that Dr. Bernhaug carefully read my discussion of his article in the Septem-
ber-October, 1974
issue (Vol. 2, No. 5) of the Journal of Sports Medicine. In that discussion I pointed out that the position of the forearm, during the execution of backhand or forehand stroke, will vary depend-
ing upon grip used as well as type of shot attempted (eg, underspin, topspin, slice). This variation is evident in both experienced and inexperienced players. However, m no instance have I observed the forearm to be past neutral position or m supinated position on
the backhand stroke
experienced
m
either the
inexperienced player Bernhaug andI agree that the
or
Since Dr. forearm is m pronation during the stroke, the main issue, therefore, concerns the degree of pronation observed in various strokes. In my previous discussion, !I
carefully
described forearm position in terms of &dquo;full pronation&dquo; Further, to understand the function of forearm position in properly executed strokes versus improperly executed ones, grip position must be accurately defined. Dr Bernhaug has failed to define grip position and, therefore, it is no wonder that confusion exists. In Dr Bernhaug’s article, Figures 17A through E (Kathy Kuykendall) indeed reveal the classic backhand stroke with the humerus in internal rotation and the forearm close to full pronation in the backswing phase As the stroke progresses to impact, the humerus is externally rotated (close to neutral) and the forearm begins to supinate to approximately 70 per cent pronation. In addition, Dr Bernhaug claims that the stroke demonstrated in Figures 17G and 18 is the standard backhand stroke. In fact, Figure 17G is a Wilson promotional poster of Billie Jean King executing a backhand volley. (In Figure 18 she is shown executing a high backhand volley ) These are certainly not standard backhand ground strokes as implied. In any event, neither forearm is in full pronation since the humerus is internally rotated. To repeat whatI had previously stated, there is a decided differ261
Figure 3-Classical Impact
Position of
Faulty Backhand
(Western Backhand Grip)
Bernhang has stated that the forearm, in faulty backhand, is In neutral or supination. He has failed to indicate a grip position. Dr
the
The thumb behind racquet handle is needed add forearm flexor power to a stroke lack-/ ing In shoulder and weight transfer power. The forearm, in this stroke, is In near full pronation Humeral abduction is dependent upon ball-level at Impact to
Figure
i-Cian,!,iLai Pubitiure uf
-tiality Backhand (EastGrip) at Impact Dr. Bernhang insists that the forearm is In full pronation In fact, the forearm is in mid-protern
nation as
illusion
humeral Internal
rotation creates
of full pronation.
cw
-
Figure
4-Full Pronation Faulty Backhand (Western Backhand Grip) Note minimal racquet head change from rotational position of Fig. 3
Figure
5-Full Forearm
Supination ( Western
Backhand
Grip)
Figure
262
2-Full Forearm Pronation with Eastern Grip. Note rotation of racquet head is 45 degrees greater than shown in figure 1.
Note racquet head is rotated nearly 180° from position In Figure 3 Also note no change in position of olecranon, whether forearm is
pronated or supinated.
between backhand ground strokes and backhand volley. Ball impact forces m the volley are generally greater and often totally decelerate the racquet head, forcing the forearm into sudden, forceful full pronation. It has been my experience that the most common characteristic of the faulty backhand is an exaggerated backhand grip with thumb behind the handle for additional flexor power This grip forces the forearm into full pronation if the racquet is kept perpendicular at all impact. Dr. Bernhaug’s illustrations of the faulty backhand (Figures 19A and 19B) are confusing. Although these are not the strokes of a tournament player, they clearly demonstrate the strokes of an experienced player The front shoulder is not elevated because of improper body weight transfer but is positioned to accommodate a high ball. There is, indeed, forward weight transfer and elbow flexion is similar to that of Kathy Kuykendall in Figure 17E. (The forearm is not m neutral as described.) Figure 28 is a better example of a faulty backhand, i.e , improper trunk position and weight transfer. However, the level of the racquet head, minimal elbow flexion and firm wrist is more characteristic of an experienced player attempting to demonstrate a faulty stroke. The forearm is clearly in pronation in this illustration. Dr. Bernhaug refers to Jimmy Connors’ two-handed backhand which is, indeed, one of the few world-class backhand ground strokes in which the dominant forearm is in full pronation. However, for Dr Bernhaug to disregard the role of the second arm in this two-handed stroke in the control of force overload deserves no further comment. In regard to racquet handle grip size, Dr. Bernhaug has misstated my position He has pointed out that the larger the handle, the better the control of torque This is well known. However, there are other factors to be considered’ ence
~
acceleration and impact
forces;
forearm strength vis a vis racquet weight; ~ handle size vis a vis racquet weight and balance Unduly large handles are not well-controlled ~
and
subjects some
hands to
peripheral
nerve
inpingement. Therefore, on the basis of factors other than torque control, the grip be too large. This, in no way, should be construed as a recommendation for smaller grip size,,.I have no objection to Dr Bernhaug’s statement, &dquo;Prophylaxis against developing tennis elbow would be the use of the largest tennis grip found comfortable &dquo; However, this advice leaves the patient to his own determination I have, therefore, used the available circumferential length of the ring finger as a practical guideline. We have found this method clinically successful Dr. Bernhaug is to be commended for his intensity and enthusiasm regarding solutions to the tennis elbow puzzle. His difficulty, however, in interpreting his own illustrations and his failure to appreciate other pertinent factors are a disappointment I would like to take this opportunity to emphasize certain factors in the etiology of tennis elbow, which have been noted in a preliminary review of our first four hundred cases of tennis elbow. I Extensor overload and player’s age are dominant factors. 2. Extensor overload can occur in forearm positions varying from full pronation to neutral 3. Clinical symptoms of tennis elbow can be initiated by stressfull grip. These symp-
can
toms
are
characteristically exaggareated
when the forearm is in full pronation. 4. The tension of the forearm extensor musculotendinous unit is increased by full forearm pronation. It is clear that much biomechanical data needs to be collected prior to a complete appreciation of all of the force-load mechanisms involved in the etiology of tennis elbow. Strain gauge and EMG testing of tennis racquets are a start. However, their lack of sophistication gives us little meaningful information about the human body itselfI am hopeful that improved methods of investigation including high-speed motion picture analysis, radiotelemetry and infrared techniques, will yield more information in years to
come
ROBERT P. NIRSCHI, M.D.
Arlington, Virginia 263
"Gamekeeper’s Thumb" Sirs I wish to thank Dr. McCue for his very interesting and knowledgeable discussion of our paper, Treatment of &dquo;Gamekeeper’s Thumb&dquo; in Hockey Players (J Sports Med, Vol. 3, No. 4, July-Aug 1975). We agree with all of his comments; and especially in his statement that m complete tears, surgical reconstruction is indicated and necessary. All the players in our series have had only partial tears of the ligaments. It was for this reason that they regamed normal pinch strength after their period of immobilization.I am sure that sooner or later we will see a complete tear which will result m residual instability after the usual period of conservative therapy. We certamly agree that surgical reconstruction would be indicated in that situation. GEORGE D. ROVFRE, M.D. Assistant Professor Section of Orthopedic Surgery The Bowman Gray School of Medicine
Winston-Salem, North Carolina
Etiology
of tennis elbow
The following comments of Dr. Robert P. Nirschl are in reply to Dr. Bernhaug’s letter an Tennis Elbow which appeared in The Journal of Sports Medicine, Vol. 3, No. 4,1975 Sirs: I suggest that Dr. Bernhaug carefully read my discussion of his article in the Septem-
ber-October, 1974
issue (Vol. 2, No. 5) of the Journal of Sports Medicine. In that discussion I pointed out that the position of the forearm, during the execution of backhand or forehand stroke, will vary depend-
ing upon grip used as well as type of shot attempted (eg, underspin, topspin, slice). This variation is evident in both experienced and inexperienced players. However, m no instance have I observed the forearm to be past neutral position or m supinated position on
the backhand stroke
experienced
m
either the
inexperienced player Bernhaug andI agree that the
or
Since Dr. forearm is m pronation during the stroke, the main issue, therefore, concerns the degree of pronation observed in various strokes. In my previous discussion, !I
carefully
described forearm position in terms of &dquo;full pronation&dquo; Further, to understand the function of forearm position in properly executed strokes versus improperly executed ones, grip position must be accurately defined. Dr Bernhaug has failed to define grip position and, therefore, it is no wonder that confusion exists. In Dr Bernhaug’s article, Figures 17A through E (Kathy Kuykendall) indeed reveal the classic backhand stroke with the humerus in internal rotation and the forearm close to full pronation in the backswing phase As the stroke progresses to impact, the humerus is externally rotated (close to neutral) and the forearm begins to supinate to approximately 70 per cent pronation. In addition, Dr Bernhaug claims that the stroke demonstrated in Figures 17G and 18 is the standard backhand stroke. In fact, Figure 17G is a Wilson promotional poster of Billie Jean King executing a backhand volley. (In Figure 18 she is shown executing a high backhand volley ) These are certainly not standard backhand ground strokes as implied. In any event, neither forearm is in full pronation since the humerus is internally rotated. To repeat whatI had previously stated, there is a decided differ261
Figure 3-Classical Impact
Position of
Faulty Backhand
(Western Backhand Grip)
Bernhang has stated that the forearm, in faulty backhand, is In neutral or supination. He has failed to indicate a grip position. Dr
the
The thumb behind racquet handle is needed add forearm flexor power to a stroke lack-/ ing In shoulder and weight transfer power. The forearm, in this stroke, is In near full pronation Humeral abduction is dependent upon ball-level at Impact to
Figure
i-Cian,!,iLai Pubitiure uf
-tiality Backhand (EastGrip) at Impact Dr. Bernhang insists that the forearm is In full pronation In fact, the forearm is in mid-protern
nation as
illusion
humeral Internal
rotation creates
of full pronation.
cw
-
Figure
4-Full Pronation Faulty Backhand (Western Backhand Grip) Note minimal racquet head change from rotational position of Fig. 3
Figure
5-Full Forearm
Supination ( Western
Backhand
Grip)
Figure
262
2-Full Forearm Pronation with Eastern Grip. Note rotation of racquet head is 45 degrees greater than shown in figure 1.
Note racquet head is rotated nearly 180° from position In Figure 3 Also note no change in position of olecranon, whether forearm is
pronated or supinated.
between backhand ground strokes and backhand volley. Ball impact forces m the volley are generally greater and often totally decelerate the racquet head, forcing the forearm into sudden, forceful full pronation. It has been my experience that the most common characteristic of the faulty backhand is an exaggerated backhand grip with thumb behind the handle for additional flexor power This grip forces the forearm into full pronation if the racquet is kept perpendicular at all impact. Dr. Bernhaug’s illustrations of the faulty backhand (Figures 19A and 19B) are confusing. Although these are not the strokes of a tournament player, they clearly demonstrate the strokes of an experienced player The front shoulder is not elevated because of improper body weight transfer but is positioned to accommodate a high ball. There is, indeed, forward weight transfer and elbow flexion is similar to that of Kathy Kuykendall in Figure 17E. (The forearm is not m neutral as described.) Figure 28 is a better example of a faulty backhand, i.e , improper trunk position and weight transfer. However, the level of the racquet head, minimal elbow flexion and firm wrist is more characteristic of an experienced player attempting to demonstrate a faulty stroke. The forearm is clearly in pronation in this illustration. Dr. Bernhaug refers to Jimmy Connors’ two-handed backhand which is, indeed, one of the few world-class backhand ground strokes in which the dominant forearm is in full pronation. However, for Dr Bernhaug to disregard the role of the second arm in this two-handed stroke in the control of force overload deserves no further comment. In regard to racquet handle grip size, Dr. Bernhaug has misstated my position He has pointed out that the larger the handle, the better the control of torque This is well known. However, there are other factors to be considered’ ence
~
acceleration and impact
forces;
forearm strength vis a vis racquet weight; ~ handle size vis a vis racquet weight and balance Unduly large handles are not well-controlled ~
and
subjects some
hands to
peripheral
nerve
inpingement. Therefore, on the basis of factors other than torque control, the grip be too large. This, in no way, should be construed as a recommendation for smaller grip size,,.I have no objection to Dr Bernhaug’s statement, &dquo;Prophylaxis against developing tennis elbow would be the use of the largest tennis grip found comfortable &dquo; However, this advice leaves the patient to his own determination I have, therefore, used the available circumferential length of the ring finger as a practical guideline. We have found this method clinically successful Dr. Bernhaug is to be commended for his intensity and enthusiasm regarding solutions to the tennis elbow puzzle. His difficulty, however, in interpreting his own illustrations and his failure to appreciate other pertinent factors are a disappointment I would like to take this opportunity to emphasize certain factors in the etiology of tennis elbow, which have been noted in a preliminary review of our first four hundred cases of tennis elbow. I Extensor overload and player’s age are dominant factors. 2. Extensor overload can occur in forearm positions varying from full pronation to neutral 3. Clinical symptoms of tennis elbow can be initiated by stressfull grip. These symp-
can
toms
are
characteristically exaggareated
when the forearm is in full pronation. 4. The tension of the forearm extensor musculotendinous unit is increased by full forearm pronation. It is clear that much biomechanical data needs to be collected prior to a complete appreciation of all of the force-load mechanisms involved in the etiology of tennis elbow. Strain gauge and EMG testing of tennis racquets are a start. However, their lack of sophistication gives us little meaningful information about the human body itselfI am hopeful that improved methods of investigation including high-speed motion picture analysis, radiotelemetry and infrared techniques, will yield more information in years to
come
ROBERT P. NIRSCHI, M.D.
Arlington, Virginia 263
