Visual Biofeedback assists Balance Training of a left Above-Knee (AK) Amputee to improve Golf Performance: A Case Study
Dynamic Balance System helping the
disabled golfer
Daniel F. Goldstein, MS, PT, OCS, SCS, ATC
Owner, Advanced Orthopedic and Sports Physical Therapy, Inc.,
West Palm Beach, FL
Rick Bradshaw, PGA Teaching Professional
Director of Golf Instruction, Jim Dent - Rick Bradshaw School of Golf,
Pebble Creek C.C., Tampa, FL
Abstract:
Efficient and consistent ball striking in golf requires good balance. Learning the "feel" of balanced movement and good posturing helps achieve a better address position. Dynamic balance, with proper weight transfer during the swing, is fundamental to being successful in golf. The use of computer-assisted visual biofeedback, with professional instruction, improves kinesthetic awareness of proper body rotation during golf. This case study reports on improved golf performance of a left AK amputee.
Key Words: balance, proprioception, kinesthetic awareness, golf-specific performance
The ability to efficiently and consistently strike the ball is a prerequisite for success in golf. According to Larry Nelson,7 PGA Teaching Professional, "Proper balance is the most important factor in striking the ball well." George Knudson,6 former PGA Tour Professional, discussed the importance of (1) static balance including proper posture and weight distribution at address and (2) dynamic balance as the appropriate weight transfer during the swing resulting in a stable finish position. According to the PGA Teaching Manual, "dynamic balance is one of golf's fundamentals which doesn't allow for much latitude!"8
Balance during movement is a highly integrated process of the neuromuscular system.5 Sensory input from specialized nerve endings in the joints, skin, and muscles (proprioceptive afferent input) as well as visual and vestibular input provides neural signal transmission to the central nervous system. The result is our "feeling" of joint position (or proprioception) during the static address position and kinesthetic (sense of joint movement) acuity during dynamic activity.3 The motor control of balanced movement is mediated by spinal reflexes, the brain stem, and cognitive programming. Through repetitive training an automatic, noncognitive response can be developed;3 erroneously referred to, by golfers, as "muscle memory."
Biomechanical studies of the golf swing have utilized center-of-pressure (COP) or center-of-gravity (COG) measurements to assess balance.1 Less movement of the COP, in an anterior-posterior direction (heel to toe movement) was observed in professional golfers when compared to higher handicap players.1,9 Brakeville et al2 noted that "maintaining balance, even in movement, is the foundation of good performance."
Poor balance, during a swing, will result in excessive or compensated movement of the player's COG. Michael Hebron,4 PGA Master Professional, has noted that "most unnecessary and unorthodox movements…in the golf swing are…compensations for a swing that has moved off center and out of balance. These unwanted actions are being introduced automatically by the central nervous system as a reaction to the body and swing being out of balance, and the only way to stop them is to improve balance!" Compensatory swing movements are more likely to result in decreased consistency and can cause greater orthopaedic stresses.
Balance training has been enhanced with the use of visual feedback techniques.5 The Dynamic Balance System*-DBS™ utilizes a force platform and computer monitor to providing a real-time display of movement of a golfer's center-of-gravity (COG) at address and through the swing. Immediate visual feedback aides the athlete to "learn the feel" of an improved, balanced weight transfer during the swing. The Appendix provides additional information about the DBS's capabilities.
Balance training is an essential aspect of rehabilitation for an above-knee (AK) amputee to assist in development of normalized movement patterns. The lost of neurological input from the knee and lower leg requires extensive training for an AK amputee to become proficient in sports activities. Without appropriate proprioceptive re-education the AK amputee may develop compensatory movements and incorrect muscular firing patterns resulting in abnormal joint stresses, irritation and biomechanical breakdown.
CASE STUDY
RG is a 43-year-old left above-knee (AK) amputee who was injured in a motorcycle accident 24 years ago. Post-operatively, he progressed well in Physical Therapy, eventually achieving good upper leg strength, an excellent gait pattern and participated regularly in racquetball. He started playing golf 6 years ago but took only a few lessons. His golf swing was inconsistent and he maintained an average score above 120 strokes.
The DBS was utilized to evaluate static weight distribution at address (Fig. 1) and the dynamic movement of his COG during the golf swing (Fig. 2). At the top of his backswing, excessive sway to the right was observed (Fig. 3). Therefore, his left leg appeared unweighted, which caused difficulty returning toward the left for ball contact.
This golfer was instructed in attaining a properly balanced address posture (Fig. 4). The visual feedback capabilities of the DBS integrated with the proprioceptive input from his hip, pelvis, lumbar spine and upper left leg allowed for him to "feel" and repeat a balanced address posture. Suggestions from author, R.B., were provided for improving his grip, alignment, and swing motion.
Our goal was for RG to learn to swing the golf club within his base of support with his COG tracing staying within our "balance zone" (See Appendix). The aim of our instruction was to learn the "feel" of having his COG move, at least, back to the center balance position (or preferably just left of center) at ball contact (Fig. 5). Upon continued trunk rotation to the left, after ball strike, RG had difficulty maintaining a balanced finish position over his prosthetic leg. Therefore, he was asked to complete his swing and take a step toward the target. With practice, a repetitive balanced swing pattern was learned (Fig. 6).
RG currently (Fig. 7) demonstrates improved consistency, greater hitting distance, and better accuracy during pitching and chipping, with a 19 handicap! More importantly, he reports decreased low back pain.
FIGURE 1. Indicates that upon addressing the ball (static balance) this client maintained his weight excessively on the right side and forward, toward his toes. His poor address posture was observed to include excessive spinal side-bending to the right while reaching too far forward for the ball.
FIGURE 2. Graph presentation of this client's dynamic COG movement while swinging a 5 iron. During the backswing his COG movement was deep toward the right heel (red line). The forward swing (blue line) indicates no weight transfer to the left prior to ball contact (X).
FIGURE 3. Client's backswing (with 5 iron) involved a sway over the right leg resulting in the left leg becoming unweighted. Therefore, his weight stayed on the right leg at ball contact.
FIGURE 4. With instruction and assistance of the DBS's immediate visual feedback, a balanced address position was attained. Client was taught the "feel" of proper rotation within his base of support.
FIGURE 5. After 2 lessons, his swing graph demonstrated improved weight transfer to the left. Note the position of his COG at ball strike (X) is within our "balance zone" but still slightly to the right of center.
FIGURE 6. With practice (utilizing visual feedback) and exercises for improved stability this client freely allowed his body to rotate over the left hip after ball contact. Better weight transfer was indicated by migration of the "X" toward the left. A repeatable balanced movement pattern is necessary for consistent sports performance.
FIGURE 7. A much improved finish position. After hitting the ball this client pivoted over his prosthetic leg and then stepped toward the target.
CONCLUSION
Accurate feedback is required to train an efficient, biomechanically sound movement pattern. The golf swing, which requires minimal compensation, will result in improved performance while reducing the risk of injury. Biomechanical efficiency begins with balance.2 Immediate visual feedback coordinated with the sensory input of the proprioceptive system allows the athlete to properly train sports-specific movement patterns.
Please contact Dan Goldstein for article reprints.
Article References
- Barrentine SW, Fleisig GS, Johnson H, Woolley TW. Ground reaction forces and torques of professional and amateur golfers. In: Cochran AJ, Farrally MR, eds. Science and Golf II: Proceedings of the World Scientific Congress of Golf, E & FN Spon, London; 1994:33-39.
- Brakeville R, Orme TJ, Chappuis JL, Covatta C. Help patients make par without pain. Biomechanics. May 1998: 55-57.
- DeMont R, Lephart S. Repetition drives neuromuscular recovery after ACL injury. Biomechanics. April 1998: 31-37.
- Hebron M. Personal communications. 1999.
- Kauffman TL, Nashner LM, Allison LK. Balance is a critical parameter in orthopedic rehabilitation. Orthopaedic Physical Therapy Clinics of North America. 1997; 6:43-78.
- Knudson G, Rubenstein L. The Natural Golf Swing. Bellevue, WA: Kirsh & Baum Publishers; 1988.
- Nelson L. Develop good balance as the keystone to a solid swing. Senior Golfer Magazine. Aug1998: 41-46.
- PGA Teaching Manual: The Art and Science of Golf Instruction. PGA of America; 1990; 138.
- Richards J, Farrell M, Kent J, Kraft R. Weight transfer patterns during the golf swing. Research Quarterly for Exercise and Sports. 1985: 56(4): 361-365.
- Cowan C. Personal communications. 2001.