Consensus statement on epidemiological studies of medical conditions in tennis, April 2009

BACKGROUND

The reported incidence, severity and nature of injuries sustained in tennis vary considerably between studies. While some of these variations can be explained by differences in sample populations and conditions, the main reasons are related to differences in definitions and methodologies employed in the studies.

OBJECTIVE

This statement aims to review existing consensus statements for injury surveillance in other sports in order to establish definitions, methods and reporting procedures that are applicable to the specific requirements of tennis.

DESIGN

The International Tennis Federation facilitated a meeting of 11 experts from seven countries representing a range of tennis stakeholders. Using a mixed methods consensus approach, key issues related to definitions, methodology and implementation were discussed and voted on by the group during a structured 1-day meeting. Following this meeting, two members of the group collaborated to produce a draft statement, based on the group discussions and voting outcomes. Three revisions were prepared and circulated for comment before the final consensus statement was produced.

RESULTS

A definition of medical conditions (injuries and illnesses) that should be recorded in tennis epidemiological studies and criteria for recording the severity and nature of these conditions are proposed. Suggestions are made for recording players' baseline information together with recommendations on how medical conditions sustained during match play and training should be reported.

CONCLUSIONS

The definitions and methodology proposed for recording injuries and illnesses sustained during tennis activities will lead to more consistent and comparable data being collected. The surveillance procedures presented here may also be applicable to other racket sports.

Growth failure in Prader-Willi syndrome is secondary to growth hormone deficiency

Growth failure is a recognized feature of the Prader-Willi syndrome (PWS). Despite evidence that hypothalamic dysfunction accompanies the syndrome, the etiology of this growth failure remains controversial because most patients with PWS are obese. In order to contribute to resolution of this controversy, we performed a retrospective analysis of 16 obese and non-obese PWS children. GH deficiency was diagnosed in 12 of the 16 subjects and occurred independently of weight status. All of the non-obese subjects were GH deficient. Of the 4 GH-sufficient children, 2 were moderately obese and 2 were morbidly obese. One of these children had clinical evidence of GH deficiency including a low IGF-1 level. Only one of the children had evidence of GH deficiency and a normal IGF-1 level, a pattern that could be attributable to obesity. We conclude that most short children with PWS have growth hormone deficiency and that this deficiency probably results from hypothalamic dysfunction.

Psychogenic basilar migraine: report of four cases

We discuss four patients with the clinical diagnosis of basilar migraine and suspected coexisting epilepsy who were referred to our epilepsy center. Their symptoms suggested episodic dysfunction in the distribution of the basilar artery, followed by pulsating headache with nausea. Verbal unresponsiveness and sensory symptoms occurred in all four patients; two also had focal paresis or jerking movements. Diagnostic studies excluded other disorders with similar symptoms. None of the patients improved with antimigraine or antiepileptic drugs. Provocation tests with suggestion elicited typical events in three patients and aura and headache in one patient. There were no EEG or ECG abnormalities during spontaneous or provoked episodes. Two patients improved with psychiatric treatment. Conversion disorder or malingering should be considered in patients whose symptoms of basilar migraine are atypical or refractory to treatment.

Low back injury

Low back injuries occur commonly in tennis, but the pathophysiologic, biomechanical, and clinical characteristics are not well defined. Tennis players may be at an increased risk of lumbar disc pathology from rotational and hyperextension shearing effects. Treatment of low back injury at present is empiric, but sport-specific lumbar stabilization and unloading of the lumbar disc should be developed. Prospective longitudinal research protocols are needed to study the lumbar spine in tennis players.

Headache

Headache is very common among women of childbearing age and can be influenced by hormonal fluctuations. When pregnant women develop headache, the cause is usually tension-type headache or migraine, but headache may be a symptom of a more serious neurologic or medical condition. This article discusses the differential diagnosis and management of major causes of headache during pregnancy.

Nerve injuries

Sports medicine physicians should be able to recognize and manage peripheral nerve injuries in athletes. Most often, the injury is a result of repetitive microtrauma, linking peripheral nerve injury to other musculoskeletal injuries in athletes. As with other musculoskeletal injuries, rest and a modification of the athlete's regimen often lead to clinical improvement. If the physician is uncertain about the diagnosis, if the athlete develops a rapid worsening of symptoms and signs, or if the athlete is refractory to treatment, a physician who specializes in peripheral nerve injuries should be consulted.

Ataxia in epidural spinal cord compression

Nine patients presented with ataxia as the primary manifestation of epidural spinal cord compression. Eight had known cancer, the ninth an epidural abscess. Lower-extremity dysmetria, gait ataxia, or both, were the only neurologic signs in five patients. An incorrect initial diagnosis led to delay in treatment and subsequent neurologic deterioration in six patients. Failure to recognize isolated, painless ataxia as the initial manifestation of spinal cord compression and appropriately treat the disorder can result in irreversible spinal cord deterioration.

Use of the Dementia Rating Scale as a test for neuropsychological dysfunction in HIV-positive i.v. drug abusers

Intravenous drug abusers (IVDAs) represent an increasing proportion of the HIV epidemic. Forty-three IVDA's (22 HIV-negative, 21 HIV-positive) were studied using the Mattis Dementia Rating Scale (DRS). All subjects had used intravenous heroin, but reported that they were drug-free at the time of testing. HIV-positive subjects were predominantly symptomatic and were dichotomized into AIDS and non-AIDS groups. All subjects with abnormal DRS scores were HIV-positive (57% of all HIV-positives). All HIV-negative subjects had normal DRS scores while 43% of the positive group obtained such scores. The DRS reliably identifies neuropsychological impairment, and may be a useful screening tool in this population.

Relation of personality and attentional factors to cognitive deficits in human immunodeficiency virus-infected subjects

In view of the evidence that patients with human immunodeficiency virus infection experience reactive depression and anxiety, it is important to determine whether these factors might account for some of the cognitive deficiencies observed in this group, as is often the case in psychiatric populations. An extensive battery of cognitive, personality, and attention tests was administered to 26 patients who tested positive for the human immunodeficiency virus. In this group were patients who demonstrated no symptoms, patients who had acquired immunodeficiency syndrome-related complex, and patients who had acquired immunodeficiency syndrome. Pearson Product Moment correlations were computed between scores on the three types of measures. The results of this correlational study suggest that cognitive decline in patients infected with human immunodeficiency virus is independent of mood and attentional changes.

Use of diastolic velocity ratios to predict significant carotid artery stenosis

Duplex scanning of the carotid bifurcation has emerged as an accurate noninvasive means of predicting and quantifying carotid arterial stenoses. Compared with the more widely reported measurements of spectral broadening and peak frequency ratios, measurements of diastolic velocity ratios have theoretical advantages in predicting carotid artery stenosis. The use of diastolic velocity ratios between the internal and common carotid arteries was prospectively studied in 30 consecutive patients to determine its accuracy in predicting significant stenosis of the internal carotid artery when compared with angiography. A total of 55 carotid bifurcations were studied, and the use of diastolic velocity ratios correctly predicted high-grade stenosis (greater than or equal to 75% diameter reduction) in 52 cases (95%). We conclude that diastolic velocity ratios may be used to accurately detect significant internal carotid artery stenosis.

Vertebral artery injury and cerebellar stroke while swimming: case report

A twenty-five year old woman suffered the acute onset of dysequilibrium followed by headache, nausea, vomiting, vertigo, and slurred speech while swimming. Brain imaging revealed a right cerebellar infarct. Intravenous digital subtraction angiography showed a hypoplastic right vertebral artery and focal narrowing of the dominant left vertebral at the level of the C1-C2 junction. The patient was treated with aspirin and dipyridamole and immobilized for two weeks. She achieved almost complete recovery. Repeat angiography showed resolution of the left vertebral artery defect. Other cases of posterior circulation infarction associated with head turning during sports and ordinary activities are reviewed.