Upper Extremity Golf Injuries (P2)
Golf instructors and golf medicine experts have divided the swing into phases: address, backswing, downswing, impact, and follow-through. Each phase of the swing places stress on different aspects of the upper extremities, and there are characteristic injuries associated with each phase. Thinking about the golf swing in this way is helpful when diagnosing and treating an injured golfer. The following discussion of golf injuries are in reference to a right-handed golfer.
The starting point in the golf swing is the address. The golfer should stand a comfortable distance from the ball with his or her feet about shoulder-width apart and body weight centered between the feet. The knees and hips are flexed to place the golfer in an athletic position while keeping the spine neutral. The arms should drape down naturally at ease from the shoulders. The club should be gripped as lightly as possible in order to minimize tension in the swing. Imaginary lines drawn across the shoulders, hips, and knees should all be parallel to each other and the target line. Mistakes in the address position lead to faults later in the swing that can cause injury as well as lead to worse ball striking and scoring.
During the backswing, the club is elevated to its highest position while the shoulders and hips rotate around the spine’s axis, and the body weight shifts toward the right foot. At the top of the swing, the wrists are cocked in maximal radial deviation, and the forearm muscles are stretched. This maneuver loads the body for generation of clubhead speeds in excess of 100 mph in less than two-tenths of a second. Repetition and swing flaws can lead to wrist and elbow tendonitis, wrist impaction syndromes, peripheral neuropathies, and shoulder impingement syndrome.
The downswing begins with the hips rotating towards the target while the weight shifts towards the left side. This lower body turn initiates the club’s downward descent while the wrists remain cocked until just before impact to create power. The most active muscles during this phase are the abdominals, pectoralis major, subscapularis, and latissimus dorsi muscles. Repetition and swing flaws in the downswing can lead to wrist, elbow, or rotator cuff injuries.
The impact phase involves striking the ball, ground, or both. The majority of traumatic injuries occur at impact. Professionals and high-level amateurs often deliberately strike the turf at impact taking a divot. Amateurs can injure themselves by hitting shots “fat,” which is an unintentional ground strike just prior to ball impact. Golfers can also be injured at impact by striking unseen tree roots, rocks, and other objects lying near the ball or by hitting a ball out of very thick or long grass.
During the follow-through phase, the body continues to rotate until facing the target. The left forearm supinates as the right forearm pronates and weight shifts almost completely to the left foot. The club decelerates to a rest over the lead shoulder. Approximately, 25% of all golf injuries occur during the follow-through. Back injuries account for 40%, and the shoulder is involved in about 17% of cases.
The shoulder is a common source of pain in golfers. It ranks as the third and fourth most common site of injury in professionals and amateurs, respectively. Most of these are overuse injuries. Professional golfers routinely perform over 2,000 swings per week. Because golfers can play the sport for life, the damage from repetitive microtrauma makes many players vulnerable to injuries.
A successful golf swing requires a synchronized effort of the shoulder girdle and rotator cuff muscles. Jobe looked at professional golfers’ shoulder muscle activity during the golf swing with electromyography. The subscapularis muscle was the most active in the shoulder girdle. The rotator cuff muscles of both shoulders were equally active during the golf swing. The deltoids were found to be relatively inactive throughout the entire swing. This is due to the fact that the shoulders do not require much elevation during the swing. The pectoralis major and latissimus dorsi muscles were very active during the acceleration of the downswing contributing to power. The investigators concluded that for increased power and injury prevention one should target rotator cuff, pectoralis major, and latissimus dorsi strengthening.
Acromioclavicular Joint Problems
The acromioclavicular joint is a common source of symptoms in golfers experiencing shoulder pain. In 1995, Mallon and colleagues reported on 35 high-level golfers with shoulder pain and found 53% had acromioclavicular joint disease as the cause of symptoms. The repetitive adduction of the lead shoulder at the top of the backswing places added load on the acromioclavicular joint. Over time this leads to spurring along the undersurface of the joint and can cause associated symptoms from rotator cuff impingement and bursal-sided rotator cuff tears. Over the years with repetitive stress, acromioclavicular joint arthrosis can develop leading to pain and stiffness.
Golfers can experience several forms of impingement syndromes in the lead shoulder. With external impingement, the golfer experiences pain when the rotator cuff impinges between the greater tuberosity and acromion upon shoulder elevation due to a decrease in the normal subacromial space from acromial spurs and inflamed bursal tissue. Rotator cuff tendonitis or partial tears can result. Rotator cuff tendonitis and impingement have been reported to be the second most common cause of shoulder pain in elite golfers.
Internal impingement, a common diagnosis in overhead athletes, can also occur in golfers in the lead shoulder at the top of the backswing and the end of the follow-through. At the top of the backswing, the lead shoulder is maximally adducted causing the humeral head and rotator cuff to impinge against the anterior glenoid and labrum. The reverse situation occurs at the end of the follow-through. The lead shoulder is abducted and externally rotated resulting in humeral head and cuff impingement against the posterior glenoid rim and labrum. Labral tears, articular-sided rotator cuff tears, and humeral head articular lesions can result from either process.
Younger golfers can develop symptomatic instability, which most often affects the lead shoulder. The etiology is often pre-existing hyperlaxity combined with overuse. The capsuloligamentous complex can undergo stretching leading to anterior and posterior subluxation with damage to the labrum and rotator cuff. The golfer may experience pain and a “pop or clunk” at the top of the backswing. Posterior instability is symptomatic at the transition from backswing to downswing as there is a tremendous posterior force across the shoulder during this transition. Hovis and coworkers found that posterior instability was the source of symptoms in a cohort of elite golfers with left shoulder pain. Their shoulder pain and instability was present at the top of the backswing. All of the golfers in the study had a positive load-and-shift test and posterior apprehension sign. Anterior instability is usually symptomatic in the lead shoulder upon the follow-through. The golfer may have a positive load-and-shift test and anterior apprehension sign. Treatment for both conditions usually consists of an initial course of rest and physical therapy directed at strengthening the rotator cuff and scapular stabilizing muscles. Surgery is indicated when non-operative management fails to relieve symptoms. It usually entails arthroscopic capsulorrhaphy or labral repair, debridement of partial rotator cuff tears and subacromial decompression, based on the underlying pathology.
Weakness of the rhomboids and serratus anterior can lead to loss of normal scapulothoracic rhythm, or scapular lag, when there is an imbalance between the scapula and the movement of the torso. Proper strength and coordination of the scapular muscles is needed to provide a stable base for the shoulder during the golf swing. Scapular lag leads to an increase in overall shoulder injuries from the downswing to the follow-through. Treatment involves strengthening of these scapular stabilizers through formal physical therapy.
Shoulder Injury Prevention
Shoulder injuries result from excessive play, inadequate warm-up, and poor conditioning. Intensity of practice and play should be gradually increased in conjunction with proper warm up, stretching, and strengthening. Any play or practice session should begin with several minutes of stretching. Warming up for at least 10 minutes prior to play or practice has been shown to decrease the rate of injuries. Golfers should also routinely exercise and strengthen the rotator cuff and scapular muscles.