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Sport pre-participation screening for asymptomatic atlanto-axial instability (AAI) in Down Syndrome (DS) patients

22 Jun, 17 | by BJSM

Faculty of Sport and Exercise Medicine



Down Syndrome (DS) is a clinical syndrome comprising of typical facial features and various physical and intellectual disabilities due to extra genetic material on chromosome 21, with one in every 1,000 babies born in the UK affected (1). DS patients are at risk of atlanto-axial instability (AAI) although AAI can occur in other conditions, such as rheumatoid arthritis, but this position statement deals specifically with DS patients and asymptomatic AAI.

AAI, also referred to as atlanto-axial subluxation, is defined as increased movement between the 1st (atlas) and 2nd (axial) cervical vertebra joint articulation, the atlantoaxial joint (2). AAI in DS patients is due to a combination of ligament laxity and bony abnormalities of the atlantoaxial joint. AAI is reported to occur in 6.8 – 27% of the DS population (3) (4) although this varies depending on the age of the patients which you are screening. Less than 1-2% (3) (5) of these patients are then thought to later develop symptomatic AAI although the natural history and progression of AAI is not well understood (2).

The risks associated with AAI are neurological injury from excessive movement of the cervical vertebra impinging on and then damaging the spinal cord although the risk of this during sporting activities is extremely rare (2) (6). Clearly physical activity and sports participation for DS patients has many biological, psychological and social benefits (7) and the Faculty of Sport and Exercise Medicine (FSEM), United Kingdom (UK) wish to promote safe physical activity and sport for all. The FSEM, UK has therefore produced a statement regarding sport pre-participation screening for asymptomatic AAI in DS patients.

Plain lateral cervical spine radiography as a screening test for asymptomatic AAI

  • Cremers et al (6) followed up 91 asymptomatic AAI patients for 1 year after screening them with lateral cervical spine radiography, letting them either participate in unrestricted sport or restricting their sporting activities. They found no difference between the groups in terms of motor or neurological function. They concluded that there is no evidence to support plain radiography screening for asymptomatic AAI.
  • There are diagnostic inconsistencies surrounding asymptomatic AAI on plain radiography, with, for example, Morton et al (8) reporting that it occurs at 4mm whilst other authors 3mm (9) (10) and some 4.5mm (5).
  • AAI diagnosis on plain xray can also change as the patient gets older (4): in 1986 Morton et al (8) followed up 90 children aged between 4-19 yo for 5 years after screening them with plain cervical x-ray and overall the AAI prevalence decreased at follow-up.
  • Obtaining plain lateral cervical spine radiography and then the necessary measurements for AAI is technically difficult (6).
  • Symptomatic AAI is rare in DS patients (2).
  • Plain lateral cervical spine radiography (including neutral, flexion and/or extension views) cannot therefore be recommended as a screening test for asymptomatic AAI in sport (10) (6) (8) (2) (4).

Alternative sport pre-participation screening techniques for asymptomatic AAI

  • For sport pre-participation assessment, a focused history and neurological examination of DS patients should be undertaken by an appropriately qualified medical professional or chartered physiotherapist (6) (4), with the preference for the professional to be someone who cares for the patient regularly, on an ongoing basis and is therefore aware of their baseline function (6), e.g. General Practitioner (GP)/Family Physician.
  • Selby et al (10) conclude that both plain x-ray and physical examination are insensitive for screening for AAI in DS patients.
  • For the neurological examination, Morton et al advise (8) checking for gait disturbance, neck movements, tendon reflexes, and plantar responses. This is similar to British Gymnastics, who have developed their own information sheet and undertake their own screening questions, with no radiological screening (11). This is also supported by Down Syndrome Association (12).

The 3 screening questions consist of (11):

  1. Does the person show evidence of progressive Myopathy? Yes/No
  2. Does the person have poor head/neck muscular control? Yes/No
  3. Does the person’s neck flexion allow the chin to rest on their chest? Yes/No

To help with question B, the person’s neck control can be assessed by: laying the person on their back with legs straight and they are then pulled to a sitting position by their hands, with the examiner pulling them from the front (11).

Depending on the results of the neurological examination, assessment of neck control and the 3 screening questions, there will essentially be 2 options for the patient:

  • Unrestricted sports participation;
  • Restricted sports participation.

High-risk sports for DS patients and symptoms of AAI to be aware of

  • Sports considered to put DS patients at higher risk of developing symptomatic AAI include (2):
    • Gymnastics including Trampolining;
    • Diving,
    • Butterfly stroke and diving starts at swimming;
    • Pentathlon;
    • Contact sports such as martial arts, rugby and soccer;
    • High jump.
  • AAI symptoms for patients, family members, health and sport professionals to be aware of include (13) (11) (4):
    • change in gait or use of arms or hands,
    • change in bowel or bladder function,
    • neck pain,
    • stiff neck,
    • head tilt,
    • how the child positions his or her head,
    • change in general function, or weakness.
  • These ‘warning’ symptoms need to be promoted to the general population, patients, family members and health professionals, e.g. through a public health campaign (4), to allow them to act if they identify an issue.
  • Specific signs and symptoms for health professionals to be aware of when they are examining a DS patient at risk of AAI include (2):
    • Easy fatigability;
    • Difficulties in walking;
    • Abnormal gait;
    • Neck pain;
    • Torticollis or head tilt;
    • Incoordination and clumsiness;
    • Sensory deficits;
    • Spasticity;
    • Hyper-reflexia;
    • Clonus;
    • Extensor-plantar reflex;
    • Other upper motor neuron and posterior column signs and symptoms.

Acute management of symptomatic AAI

  • If you suspect symptomatic AAI, the patient’s spine should be immobilized and an urgent, same day cervical spine x-ray and MRI and neurosurgical consult arranged (5).

Promoting safe sport for DS patients

  • To facilitate safe sport for DS patients we need to promote neck conditioning exercises for this cohort of patients, similar to the neck programme promoted in patients with chronic neck discomfort (14), as well as safe sporting practices, e.g. appropriate supervision when undertaking higher risk sports such as trampolining or rugby.


Plain radiography cannot be currently recommended to screen for asymptomatic AAI. DS patients undergoing a sport pre-participation screening should have 3 questions asked as per the British Gymnastics programme and a neurological and neck control assessment undertaken. Neck conditioning exercises should be generally promoted amongst the DS population. Awareness of potential signs and symptoms of symptomatic AAI need to be raised amongst DS patients, family members and professionals caring for this group of patients as well as the need to provide appropriate supervision when DS patients are undertaking certain ‘high-risk’ sports. These measures will then allow DS patients to maximise the biological, social and psychological benefits of physical activity and sport participation.


Sources of Funding: No sources of funding were used when compiling this position paper.

Competing interests: Nil declared.

Conflicts of Interest/Disclosures: Nil

Ethical Approval: Not required.

Authors’ contributions: NH led the conception and design of the position paper and prepared the first draft of the manuscript. All authors were involved in critical revisions and reviewing background reading.  All authors critically reviewed the manuscript and approved the final version submitted for publication.  All authors read and approved the final manuscript.

Authors: Dr Christopher Tomlinson1; Dr Alastair Campbell2; Dr Alison Hurley3; Mr Eoin Fenton4; Dr Neil Heron 5, 6, 7, 8.

Email address for correspondence:

Affiliations: 1 Sport and Exercise Medicine Physician, English Institute of Sport; 2 Radiology Department, Musgrave Park Hospital, Belfast Trust; 3 Radiology department, Dublin; 4 Neurosurgery Department, Blackrock Clinic, Dublin; 5 Dept of General Practice and Primary Care, Queen’s University, Belfast; Centre for Public Health Research, Queen’s University, Belfast; 7 Centre of Excellence for Public Health Research (NI); 8 Elected Council Member of the Faculty of Sport and Exercise Medicine (FSEM), United Kingdom (UK).

Address for correspondence: Dept of General Practice, Queen’s University, Dunluce Health Centre, Level 4, 1 Dunluce Avenue, Belfast, BT9 7HR.


(1) Roizen NJ, Patterson D. Down’s syndrome. The Lancet 2003 4/12;361(9365):1281-1289.

(2) Committee on Sports Medicine and Fitness. Atlantoaxial instability in Down syndrome: subject review. American Academy of PediatricsCommittee on Sports Medicine and Fitness.. Paediatrics 1995;96(1, Part 1):151-4.

(3) Nader-Sepahi A, Casey ATH, Hayward R, Crockard HA, Thompson D. Symptomatic atlantoaxial instability in Down syndrome. Journal of Neurosurgery: Pediatrics 2005 09/01; 2017/03;103(3):231-237.

(4) Myśliwiec A, Posłuszny A, Saulicz E, Doroniewicz I, Linek P, Wolny T, et al. Atlanto-Axial Instability in People with Down’s Syndrome and its Impact on the Ability to Perform Sports Activities – A Review.. Journal of Human Kinetics 2015;12(48):17-24.

(5) Cohen W. Current dilemmas in Down syndrome clinical care: celiac disease, thyroid disorders, and atlanto-axialinstability.. American Journal of Medical Genetics 2006;142C(3):141-8.

(6) Cremers MJG, Bol E, de Roos F, van Gijn J. Risk of sports activities in children with Down’s syndrome and atlantoaxial instability. The Lancet 1993 8/28;342(8870):511-514.

(7) Andriolo R, El Dib R, Ramos L, Atallah A, da Silva E. Aerobic exercise training programmes for improving physical and psychosocial health in adults with Down syndrome.. Cochrane Database of Systematic Reviews. 2010;12(5):CD005176.

(8) Morton R, Khan M, Murray-Leslie C, Elliott S. Atlantoaxial instability in Down’s syndrome: a five year follow up study.. Archives of Disease in Childhood 1995;72(2):115-8.

(9) Roy M, Baxter M, Roy A. Atlantoaxial instability in Down syndrome–guidelines for screening and detection.. Journal of the Royal Society of Medicine 1990;83(7):433-5.

(10) Selby K, Newton R, Gupta S, Hunt L. Clinical predictors and radiological reliability in atlantoaxial subluxation in Down’s syndrome. Archives of Disease in Childhood 1991;66(7):876-8.

(11) British Gymnastics. Atlanto-axial instability information pack. British Gymnastics 2012;1(1):1.

(12) Charleton P, Dennis J.
Neck Instability (Craniovertebral Instability)
A GUIDE FOR PARENTS AND CARERS. Down Syndrome Association Health Series 2013;1(1):1.

(13) Bull MJ, Committee on Genetics. Health supervision for children with Down syndrome.. Paediatrics 2011;128(2):393-406

Should we be screening for gambling addiction in our athletes?

20 Jun, 17 | by BJSM

By Sean Carmody @seancarmody1

“On every advert you have a bet here and there. You cannot be surprised if people bet. You incite people to bet.” – Arsene Wenger

In March, the sports medicine community traveled to Monaco for their three-yearly pilgrimage.

And the hot topic? Screening in Sport.

Much of the conference debate centred on whether we could screen for (and ultimately, predict) injury in athletes. Largely thanks to Roald Bahr’s keynote (and influential paper here), there was loose consensus that it was not presently possible to accurately screen for future injury, but the screening process was still useful to detect current injury and build rapport with athletes.

Just over a month after the conference closed, the relationship between gambling and professional sport was thrust into the spotlight with the news that Joey Barton had received an 18-month ban for breaking the Football Association’s rules on gambling. Predictably, Barton came out fighting against the ban with a statement which included the following;

“Surely they need to accept there is a huge clash between their rules and the culture that surrounds the modern game, where anyone who watches or follows football on TV or in the stadia is bombarded by marketing, advertising and sponsorship by betting companies, and where much of the coverage now… is intertwined with the broadcasters’ own gambling interests… If the FA is serious about tackling gambling I would urge it to reconsider its own dependence on the gambling industry.”

While it doesn’t detract from his offence, Barton has a point. The temptation to gamble is ubiquitous, and few sports are spared from the bombardment. Rugby League, once heralded for their principled rejection of sponsorship money from gambling companies, is now host to competitions such as the BetFred Superleague and the Ladbrokes Challenge Cup. As the late narco-terrorist Pablo Escobar noted; “Everyone has a price, the important thing is to find out what it is”. In this sporting climate, it comes as no surprise that there is a long list of athletes who have succumbed to gambling addiction.

The research on athletes and gambling is relatively limited. However, Michael Calvin (who incidentally co-wrote Joey Barton’s autobiography) sheds further light on the scale of the issue in his excellent new book “No Hunger in Paradise: The Players. The Journey. The Dream”. In interviews with important figures who are combatting the problem, he ascertains that young footballers – specifically targeted due to their premature wealth – are the subject of predatory marketing material by gambling companies. This is concerning considering research which has found that rates of problem gambling are typically highest between the ages of 18 and 24. Calvin also reports that 70% of presentations to the Sporting Chance Clinic relate to gambling addiction. These findings, coupled with the high proportion of athletes who declare bankruptcy soon after retirement (according to a 2009 Sports Illustrated article 78% of NFL players are broke within 2 years of hanging up their cleats), suggests a bleak outlook for the relationship between gambling companies and professional sport.

With this in mind, should we screen our athletes for gambling addiction?

A relatively recent survey carried out in almost 350 footballers and cricketers, found that 6% met the criteria to be classed as ‘problem gamblers’ – more than three times the rate when compared with men in the general population. When you make the rough comparison between that finding and the classical epidemiological studies in football – gambling addiction is nearly as common as quadriceps strains (7%) and much more common than head injuries (2%) (Ekstrand et al., 2011). Perhaps the finding that will make key stakeholders (eg coaches, CEOs) take notice, is the additional evidence that the performance of some players is affected by worries related to their gambling habits, which often take place on the team coach or in hotels, and is (ab)used to soothe their boredom.

In summary, Joey Barton is not the first athlete, and surely won’t be the last, to become a victim of the professional sporting environment which tempts the impulsive to gamble. Further we need more research to better understand the factors which predispose athletes to gambling addiction, and sport-specific screening tools may be required. Moreover, due to its potential to affect performance and result in serious mental health issues, gambling addiction must be considered alongside commonly assessed issues in athletes such as musculoskeletal injury and cardiac screening.

Key Resources:

DSM-5 Diagnostic Criteria for Gambling Disorder.

Sporting Chance Clinic for the treatment of behavioural problems among professional and amateur sports people.

Sean Carmody is a Junior Doctor working in London. He tweets regularly on topics related to sports medicine and performance (@seancarmody1).

E-letter: Pre-participation screening in competitive athletes in Portugal

11 Mar, 10 | by Karim Khan

This E-letter is in response to ECG As A Part of the Pre-Participation Screening Programme: An Old an Still Present International Dilemma (Abstract)

Pre-participation screening in competitive athletes in Portugal has been compulsory for more than 40 years. Yearly ECG was introduced in the screening at about the same time as in Italy, for all athletes evaluated at the Sports Medicine Centres in Portugal. The very rare cases of sudden cardiovascular death that have ocurred in the past 25 years in Portugal were not screened at the Centres or had further cardiovascular evaluation pending, and threfore were not qualified for practice. Several athletes have been disqualified from sports participation for cardiovascular reasons, most of them were further investigated because of rest ECG changes findings. We strongly favour the use of 12 lead ECG in the pre- participation screening process. Presently, we routinely screen about 20.000 athletes per year in the 3 Sports Medicine Centres in Portugal.

Marcos A. Miranda
Sports Medicine Specialist
Lisbon Sports Medicine Centre

TIME Magazine: Screening for Sudden Cardiac Death

23 Sep, 09 | by Karim Khan

This month TIME Magazine‘s website, picked up on BJSM’s IOC IssueScreening for Sudden Cardiac Death. Read the article at here.

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