**24. Unusual causes of leading medial wrist injuries in golfers**

Rare causes of leading wrist injury in golfers include damage to the Flexor Carpi Ulnaris tendon and proximal entrapment of the ulnar and median nerves, these are rare in golf but are commonly encountered in the general sporting population and among gym users (**Figure 21**).

The Flexor Carpi Ulnaris (FCU) muscle has its origin at the medial epicondyle and it is inserted on the medial side of the wrist into the pisiform, hamate and the base of the 5th metacarpal bone. 5th carpal by a tendinous attachment. The FCU acts as a flexor and ulnar deviator of the wrist. Injury therefore can occur at impact with the ball during the golf swing as the wrist converts into a flexed and ulnar deviated position at impact. In cases of acute trauma, the injury is usually located distally at the level of the pisiform bone insertion. In cases of overuse injuries, the injury is usually proximal to the wrist at the level of the musculotendinous junction. Diagnosis is confirmed by careful palpation of the full length of the tendon. Pain is exacerbated by resisted wrist flexion and ulnar deviation. Ultrasound of the full length of the nerve confirms the diagnosis. The FCU tendon can be also compromised in injuries to the hook pf the hamate bone.

The ulnar nerve can be compromised at the elbow in cases of medial epicondylitis or "golfers elbow". The ulnar nerve travels through the cubital tunnel prior to entering the ulnar groove as it travels caudally. The cubital tunnel is formed by bone, ligament and muscle.

The tunnel's ceiling is formed by the cubital retinaculum, a ligament spanning from the medial epicondyle to the olecranon process that is continuous with the fascia connecting the humeral and ulnar heads of the flexor carpi ulnaris (FCU).

**Figure 21.** *Proximal entrapment of the median nerve by the pronator Teres muscle.*

Injury to these structures or to the flexor tendon insertion at the medial epicondyle can compromise the ulnar nerve resulting in a local irritation or compression of the ulnar nerve, known as Cubital Tunnel Syndrome. Golfers elbow is associated with golf and racket sports. Repetitive activity and holding the elbow in flexion at impact can be aetiological elements in the development of the tendon injury which may be a prequel to the local ulnar nerve irritation. The increased in elbow flexion causes the arcuate ligament to tighten, the FCU to tighten and the ulnar collateral ligament to buckle and encroach into the tunnel compromising the ulnar nerve [59, 60].

This can cause numbness and tingling in the hand and/or ring and little finger, especially when the elbow is bent. Occasionally a player will describe hand pain in the hypothermal eminence when swinging a golf club and weakness when gripping a club and a lack of consistency in golf grip due to muscle weakness in the intrinsic muscles of the hand which receive their innervation from the ulnar nerve.

Diagnosis is made by identifying the clinical signs of an ulnar neuropathy. Electrodiagnostic evaluation with Nerve Conduction Studies and needle EMG. Conservative treatment includes rest and Ultrasound guided injection therapy at the cubital tunnel. In chronic cases surgical release may be required.

Distal median neuropathies can also occur in the golfing population. It is well recognised in racket players [61]. This is referred to as pronator syndrome. The nerve can be compromised at 4 sites in the flexor aspect of the forearm.

The Ligament of Struthers is present in up to 2.7% of the population [62, 63]. Entrapment of the nerve at this site is exacerbated by elbow flexion and extension [63] which is a common manoeuvre in the leading arm of a golfer.

The median nerve travels through the 2 heads of the Pronator muscle just below the elbow joint, and can be compromised at this site. The nerve can also be entrapped by thickening of the bicipital aponeurosis, and finally by the flexor digitorum superficialis. These flexor and pronator muscles are frequently hypertrophied from overuse activities such as repeated golf swinging and practice, particularly in golfers with strong grips (pronated flexed wrists). With this grip the pronator testes muscle has to fire quickly at impact in an effort to square up the club face. The median nerve becoming entrapped at this proximal site. Symptoms are often vague and can suggest a mixed pattern of median and ulnar nerve symptoms. Diagnosis involves electrodiagnostic assessment. Treatment requires rest and alteration in technique and practice protocols. In resistant cases surgery is indicated.
