Revista de Medicina Desportiva (English) September 2018 | Page 23

described in athletes, in the third decade of life, victims of minor CET, without severe brain hemorrhagic lesions. The autopsies revealed CM1, no signs of syringomyelia, but with herniation of the cerebellar tonsils down to the 7 th cervical vertebra (about 110mm in relation to fora- men magnum). 9,10 In 2014, Wang H describes the case of a 23-year-old athlete, a victim of CET after a fall of his own height. He started with occipital headaches, ataxia, dyspha- gia and tetraparesis. The neuroradio- logical exams revealed CM1 without syringomyelia, signs of obstruction of the 4 th ventricle and a hernia- tion of 18mm. A craniectomy of the posterior fossa was performed, associated with the removal of the posterior arc of C1 as an emergency procedure, with complete resolu- tion of the neurological problrms in thirty days. 11 Strahle and Meehan conducted retrospectives studies in 650 young athletes with diagnosis of CM1 not subjected to surgery. No case of sudden death or focal neurological injury has been recorded. 66 cases of cerebral concussion were identi- fied. 12,13 According to Clay’s study of the epidemiology of the cerebral concussion in sporting practice, the number registered corresponds to twice the cases normally refer- enced. 14 The sports-medical examination applied in Portugal does not value in a detailed way the existence of neurological signs and symptoms. In the medical evaluation of the ath- letes of CS it is important to value the existence of headaches, cervical pain and different changes of the sensitivity, both in the trunk and in the limbs. The risk for the athlete with CM1 to suffer a severe neurological injury during the CS is low. However, it is higher than in the general popula- tion. 12 The asymptomatic athletes, whose CM1 was incidentally diag- nosed, should be evaluated on a case-by-case basis. The oblitera- tion of the space subarachnoid, the presence of syringomyelia, the indentation of the anterior portion of the marrow and the presence of symptoms related to changes in the flow dynamics of cerebrospinal fluid are elements that can predispose the athlete to serious neurological deficits and they are usually strong restriction criteria. There is not enough data in the literature to indi- cate the degree of cerebellar hernia- tion that contraindicate CS practice. The presence of two or more brain concussions should not allow the CS practice. 15 The symptomatic athletes with CM1, without any imaging characteristics described before, are not usually prevented from practic- ing CS. However, both the athlete and the family should be aware of the risk and of the injuries they may be subjected to. 12,13 The posterior craniectomy decom- pression and the removal of the posterior arc of C1 is not generally recommended on the asympto- matic athletes involved on contact sports as prophylaxis for neurologi- cal lesions. The surgery is usually reserved for symptomatic athletes, being controversial in the asympto- matic patients with signs of syringo- myelia. 15,16 Conclusion The diagnosis of CM1 is an impor- tant factor for protection of the health of the athlete, particularly on DS. The sports medical examination should identify symptoms and signs that may raise the clinical suspicion that could lead to the appropri- ate imaging exams. The adequacy of sports practice and the advice of athletes and families should be considered. The return to sports of the athletes with neurological injury or athletes subjected to surgery should be much more restricted, being generally considered absolute counterindication to the practice of CS. On the athletes with greater risk of getting neurological injury, it is important to adapt the sporting activity with alternative modalities. A more systematic clinical follow- up in the neurosurgery department should be carried out. Bibliography 1. Callaway GH, O’Brien SJ, Tehrany AM. Chiari I malformation and spinal cord injury: Cause for concern in contact athletes? Med Sci Sports Exerc. 1996; 28(10):1218-1220. 2. Killory BD, Preul MC, Spetzler RF. Chiari Mal- formations. Encyclopedia of the Neurologi- cal Sciences. 2014; 770-772. 3. Tubbs RS, Oakes WJ. Introduction and classifi- cation of the chiari malformations. The Chiari Malformations. 2013; 1-3. 4. Johnston JM, Wellons JC. The Chiari mal- formations and hydrocephalus. The Chiari Malformations. 2013; 273-282. 5. Miele VJ, Bailes JE, Martin NA. Participation in contact or collision sports in athletes with epilepsy, genetic risk factors, structural brain lesions, or history of craniotomy. Neurosurg Focus. 2006; 21(4):E9. 6. Schijman E, Steinbok P. International survey on the management of Chiari I malformation and syringomyelia. Child’s Nerv Syst. 2004; 20(5):341-348. 7. Martinot A, Hue V, Leclerc F, Vallee L, Clos- set M, Pruvo JP. Sudden death revealing Chiari type 1 malformation in two children. Intensive Care Med. 1993; 19(2):73-74. 8. James DS. Significance of chronic tonsillar herniation in sudden death. Forensic Sci Int. 1995; 75(2-3):217-223. 9. Zhang J, Shao Y, Qin Z, et al. Sudden unex- pected death due to chiari type I malformation in a road accident case. J Forensic Sci. 2013; 58(2):540-543. 10. Wolf D a, Veasey SP, Wilson SK, Adame J, Korndorffer WE. Death following minor head trauma in two adult individuals with the Chiari I deformity. J Forensic Sci. 1998; 43(6):1241- 1243. 11. Wang H, Wang B, Normoyle KP, Farahvar A, Olivero WC. Chiari I Malformation with Acute Brain Stem Compression Syndromes Requiring Emergency Neurosurgical Intervention: Report of Two Cases. J Neurol Disord. 2014; 02(05). 12. Meehan WP, Jordaan M, Prabhu SP, Carew L, Mannix RC, Proctor MR. Risk of athletes with chiari malformations suffering catastrophic injuries during sports participation is low. Clin J Sport Med. 2015; 25(2):133-137. 13. Strahle J, Geh N, Selzer BJ, et al. Sports participation with Chiari I malformation. J Neurosurgery Pediatr. 2016; 17(4):403-409. 14. Clay MB, Glover KL, Lowe DT. Epidemiology of concussion in sport: A literature review. J Chiropr Med. 2013; 12(4):230-251. 15. Harrell BR, Barootes BG. The type i chiari malformation in a previously asymptomatic college athlete: Addressing the issue of return to athletic participation. Clin J Sport Med. 2010; 20(3):215-217. 16. Makela JP. Arnold-Chiari malformation type I in military conscripts: Symptoms and effects on service fitness. Mil Med. 2006; 171(2):174-176. The authors declare a lack of conflict of interest Correspondence to João P Pinheiro jpá[email protected] Revista de Medicina Desportiva informa september 2018 · 21