Sports Medicine Report: Risking Wrist Injury
By Vincent J, Walsh, P.A.


In an attempt to "rip" the water upon entry, platform divers are altering their technique from a closed fist approach to that of an open hand technique. While this method may ensure a greater likelihood of a smooth entry, it does not come without consequences. This article will attempt to review the biomechanics of this open hand technique and the types of wrist injuries that may result.

Currently, divers are using two methods to decrease splash and provide a gracefully entry into the water. The first approach requires the hands to be clinched in a fist with one thumb being grasped by the other closed hand.
The second approach, is a more recent technique, often referred to as "open hand" or "flat hand" technique. It is accomplished by grasping the dorsum of the hand and fingers of one hand with the opposite hand then extending at the wrist as far as possible. Upon water entry the wrist is in maximal extension, radial deviation and pronation
.
This position, which is now very popular among high caliber divers, attempts to punch a hole in the water as the rest of the body surges with a characteristic "rip." The rip is the end result of a minimized splash.

While this "open hand" method may improve the aesthetics and the score of a dive, it can also result in various types of wrist injuries, both acute and chronic. The most often injured wrist is that of the dominant hand. The wrist is placed in forced extension, pronation and radial deviation, which places the posterolateral aspect of the superiorly placed wrist and hand, in a compromising position that results in injury. Wrist and hand placement produce vulnerability to injury, in addition to the quantity of training, the level of skill performed, and the speed of entry into the water.

Divers can often train up to 20 hours per week with 12 hours devoted to diving, resulting in well over 200 dives per week. When a platform diver dives from 10-meters high, the diver can reach speeds of 32 mph (54.1 kn/h). These variables are coupled with an ever increasing level of difficult dives being performed with an open hand technique that may result in periostitis, stress fractures, and soft tissue damage to the capsule and ligaments surrounding the wrist bones. Some injuries that have specifically been seen are recurring sprains or subluxations of the metacarpophalangeal or carpal-metacarpal joint in platform divers.

Another contributing factor in the frequency of wrist injuries to platform divers is due to the surface area of the hands, which results in a braking system upon water entry. The surface area with the fist closed is approximately 83 cm, whereas it is 175 cm with two hands superimposed (open hand technique). This demonstrates that the open hand technique has a more significant braking effect. At the moment of entry, the body is slowed drastically from 51 km/h to 33 km/h. After this initial sudden brake, the body entry rate is unchanged. This signifies that the diver's hands are the main energy absorbers. Upon entry, there is a sudden and dramatic dorsiflexion of the wrist, which can cause impingement of the distal row of carpal bones. If the athlete, coach, or trainer is suspicious of a stress fracture in the wrist, X-ray and medical attention should be sought.

Divers and coaches also should be aware of the effects of open hand technique on the shoulder musculature. Chronic shoulder tendentious, affecting the rotator cuff, can occur as a result of the rotator cuff muscles contracting to hold the humeral head against the glenoid fossa while the arms are abducted over head. Upon entry, the arms can be further and forcibly abducted resulting in an injury to the rotator cuff. The response is usually an inflammatory one, affecting the rotator cuff tendons and/or the subdeltoid bursae. When this inflammation occurs, termed impingement syndrome, it limits the space underneath the acromion process. As this space decreases, it causes the supraspinatus tendon and biceps tendon to become impinged. The impingement occurs between the inferior aspect of the acromion and the coracoacromial ligament as the arm is raised over head. This impingement can result in further inflammation of the tendon, which results in increased pain and eventually may result in a tendon tear.

The treatment of choice for the majority of these wrist and shoulder injuries consists of rest, icing in the acute phase and heat in the subacute phase. Many divers utilize different wrist taping techniques to provide some added support against dorsiflexion. In addition to taping, some use a 4x3 cm splint placed beneath the tape o the radial side. This splint adds more support than taping alone. Warming up and stretching the wrist or shoulder, prior to diving followed by icing down after diving helps prevent joint or musculotendinous damage. Rotator cuff strengthening exercises, especially in the immature diver may also help in the prevention of shoulder injuries.

Although the literature did not specify a physical therapy protocol, it is always prudent to strengthen the soft tissue about the joint that is enduring stress in an attempt to minimize wrist trauma with open-hand technique. Strengthening is done as a preventative measure, part of rehabilitation after injury, and a means to curtail the recurrence of the injury.
A conditioning or rehabilitation program that focuses on grip strength, wrist flexors, extensors, supinators and pronators, as well as elbow flexors and extensors, should strengthen the muscles and other soft tissue about the wrist. This will attempt to prepare the body for the traumatizing forces.

Provided below is a minimally time consuming program that platform and perhaps 3-meter divers should incorporate in their conditioning regimen to optimize their performance.

Gripping
1. Place a tennis or racquetball in palm of hand.
2. Squeeze and hold for 10 seconds.

Wrist Flexion
1. Sit in a chair with tubing under foot, handle in hand, with palm up. Support forearm on thigh, with wrist and hand extended beyond knee.
2. Slowly curl wrist up as far as possible.
3. Slowly return to starting position.

Wrist Extension
1. Sit in a chair with tubing under foot, handle in hand, with palm down. Support forearm on thigh, with wrist and hand extended beyond knee.
2. Slowly raise hand and bend wrist back as far as possible.
3. Slowly return to starting position.

Forearm Supination
1. Sit in a chair with tubing under opposite foot. Hold handle in hand, with palm down. Support forearm on thigh, with wrist and hand extended beyond knee.
2. Slowly rotate forearm to palm up position.
3. Slowly return to starting position.

Forearm Pronation
1. Sit in a chair with tubing under foot about 10 inches outside center of body. Hold handle in hand, with palm up. Support forearm on thigh, with wrist and hand extended beyond knee.
2. Slowly rotate forearm to palm down position.
3. Slowly return to starting position.

Elbow Flexion
1. Sit in a chair with tubing under foot. Hold handle in hand, palm up. Support elbow on thigh, with forearm, hand and wrist extended beyond knee.
2. Slowly bend elbow up to a slowly flexed position.
3. Slowly return to starting position.

Elbow Extension
1. In a standing position, hold tubing in hand. With tubing draped over opposite shoulder, grasp behind back.
2. Straighten elbow raising arm overhead.
3. Slowly return to starting position.

Although diving is one of the safer sports, as the complexity and precision of dives increase in an attempt to take the dive or sport to the next level, so may the injuries. As divers continue to change the entry technique from the original closed fist to an open or flat hand technique, we will continue to see a rise in wrist injuries. It may be wise to seek better preventative measures or an alternative entry technique in an attempt to "rip" a dive.

Acknowledgments
I would like to thank Robert J. Daley M.D. for lending his expertise in editing this article.

References
1. Fu, Freddie H., MD, and Stone, David, MD eds. Sports Injuries, Mechanisms, Prevention, Treatment, 1994. Baltimore, Md.: Willias & Wilkins; 1994: 266-268.
2. Carter, Richard L., M.D., Prevention of Springboard and Platform Diving Injuries. Clinics in Sports Medicine, 1986; 5: 185-194.
3. Le Viet, Dominique T., M.D., Lantieri, Laurent A., M.D., Loy, Stephan M., M.D. Wrist and Hand Injuries in Platform Diving. The Journal of Hand Surgery, 1993; 18A: 876-880.
4. Netter, Frank H., M.D., Atlas of Human Anatomy. Hong Kong: Ciba-Geigy Corporation, 1989: 426.
5. Thumb, Wrist Injuries Linked to Divers' Entry. Physician and Sports Medicine, 1981; 9: 23.
6. Guten, Gary N., M.D. Play Healthy, Stay Healthy. United States: Leisure Press, 1991; 191-194.

Vincent J. Walsh is a physician assistant at Great Lakes Orthopaedics near Chicago. Walsh received a B.S. in corporate fitness with a sports medicine emphasis from Northern Illinois University. He has worked with U.S. Diving and U.S. Swimming teams and has provided medical coverage for events such as NCAA Championships, U.S. Olympic Team Trials, U.S. Diving Nationals and the Diving World Cup in Mexico City last fall.