Tennis weaknesses

Get a grip

Tennis elbow, or to give it its proper name, lateral epicondylitis, is a common injury in recreational tennis players, arising from overuse of the extensor and supinator muscles in the forearm. In particular the extensor carpi radialis brevis (ECRB) muscle, which helps to extend and radially deviate the wrist (turn in laterally towards thumb), is often implicated as having been overexerted.

Racquet manufacturers and the popular press often cite inappropriately sized tennis racquet grip as a risk factor for overuse injuries in the forearm and elbow. During the early 1980s RP Nirschl speculated that using a tennis grip size either too big or too small would cause altered muscle activity (overactivity from too tight a grip on a small racquet handle, or underactivity from too light a grip on too large a handle). Getting the grip size right would therefore reduce the effort needed to hold the racquet, increase the efficiency of the forearm and hand muscles, and reduce the potential for overuse injuries.

In the 20 years since Nirschi’s work, various studies have shown an association between tennis elbow and improper grip size, but findings are equivocal. Can something as simple as grip size be the difference between painfree playing and a career of niggling elbow injuries? If we are to believe the latest findings from US researchers, small changes in grip size will not make a difference to your client’s potential to develop tennis elbow (‘The effect of tennis racket grip size on forearm muscle firing patterns’, The American Journal of Sports Medicine, 34: 12, 19771983).

Sixteen Division I and Division II tennis players took part in the study, performing single handed backhand ground strokes with racquets of three different grip sizes: recommended, undersized Ginch and oversized Ginch. EMG data was collected on the activity levels in the main forearm muscles. The results indicated no differences in muscle firing patterns between small, recommended and large grips. Based on these findings, it would seem that varying the racquet grip size Ginch either side of Nirschi’s recommended measurement is not an effective treatment for tennis elbow.

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Physio works

Researchers from Australia have recently confirmed that the most effective treatment for tennis elbow is physiotherapy, combining elbow manipulation and exercise (‘Mobilisation with movement and exercise, corticosteroid injection, or wait and see for tennis elbow: randomised trial’, British Medical Journal 2006, 333:939). The study looked at three treatment options:

* wait and see

* corticosteroid injections, initial injection plus second injection after two weeks if deemed necessary.

* physiotherapy treatment: eight 30min sessions over six weeks consisting of elbow manipulation and therapeutic exercise, plus an exercise band and instruction booklet for home use.

The corticosteroid intervention showed significantly better effects at six weeks but there was a high rate of injury recur rence thereafter (47 out of 65 participants or 72%) and sig nificantly poorer outcomes in the long term compared to physiotherapy. Physiotherapy was superior to wait and see in the short term; but there was no difference at 52 weeks. However participants who had physiotherapy sought fewer additional treatments, such as NSAIDs, than those receiving injections or those simply left to sit it out with no treatment.

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Shoulder conditioning

Researchers from the Netherlands recently reviewed theories on the pathophysiology of painful shoulders in tennis players and have highlighted several useful guidelines to help understand and prevent shoulder overuse injuries (‘Shoulder injuries in tennis players’, British Journal of Sports Medicine, 2006: 40, 435440).

Evaluate kinetic chain function:During a serve, the shoul der is part of a kinetic chain. Research has shown that 51% of total kinetic energy and 54% of total force are developed in the leghiptrunk link, which can be defined as force ‘generators’. The shoulders can be thought of as force ‘regulators’ and the armelbowwrist act as a force ‘delivery’ mechanism. A weak link in the kinetic chain close to the body (eg leg, trunk or shoulder) creates higher demand on the more Evaluate scapular function:There are three basic alter ations in the normal position or movement pattern of the scapula (shoulder blade) during coupled scapulohumeral (shoulder) movements:

* Prominence of the inferomedial scapula border (bottom inside edge of the shoulder blade protrudes excessively), made worse during cocking position and linked to tight pec torals (major/minor) and weak trapezius and serratus anteri or muscles.

* Winging (sticking out) of the entire medial border (inside shoulder blade area) at rest, made worse during cocking position and caused by fatigue of the stabilising muscles (trapezius and rhomboids).

* Prominence of the superior medial border of the scapula (protrusion of the upper inside edge), often associated with impingement and rotator cuff injury.

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Evaluate rotator cuff muscle balance and the integrity of the capsular structure:The repetitive nature of the serve causes microtrauma of the anterior capsule. Lengthened lig aments may cause instability, which in turn may result in for ward displacement of the humeral head, leading to an impingement injury. Loss of glenohumeral internal rotation of the serving shoulder compared to the nonserving shoul der has been linked to an increased potential for injury.

Develop a structured strength and conditioning programme: A well balanced action of the scapula, rotator cuff muscles and capsular structures is necessary for the tennis player to be able to maintain a stable centre of rota tion during the overhead serving action.