MUSCULOSKELETAL DIAGNOSIS

CERVICAL SPINE INJURY IN SPORT

By Barney Kenny, MCSP, MPhty (Sports)

Anatomy and biomechanics One of the features of the cervical spine is that it must be mobile to allow correct positioning of the head for functional activities. Similarly it protects the central nervous system with the spinal cord and cervical nerve roots. Severe trauma to the cervical spine may have a devastating effect. Flexion injuries may cause damage to the cervical spine. If flexion is com- bined with rotation a more serious injury may occur resulting in tetraplegia.

Movements in the cervical spine are due to the different anatomical arrangements of the upper cervical vertebra to the lower cervical vertebra. The upper cervical spine consists of the occipital atlanto–axial complex. The middle and lower consists of C2–T1 vertebrae complex.

In both regions coupled motion exists ie. coupling refers to the motion in which rotation or translation of a body in one axis is consistently associated with simul- taneous rotation or translation about another axis.

Occipital–atlanto–axial complex The atlas (C1) articulates with the occiput and the axis (C2). It does not have a ver- tebral body but has lateral masses which have convex facets that articulate with

Cervical spine injuries commonly occur in contact sports. However non-contact sports such as diving, water-skiing and water polo sports can produce serious spinal injury. The contact sports identified as high risk of cervical spine injury are rugby, American football and wrestling. Most injuries that occur are relatively minor, however catastrophic injuries do occur ie. fractures and fracture disloca- tions of the cervical spine leading to tetraplegia. This article reviews the types of injuries that occur, particularly in rugby, along with the mechanisms of injury and advice on prevention. It is followed by a rehabilitation-based article on injuries to the brachial plexus.

Keenen and Benson (1) stated that 15% of all spinal cord injuries in a year that resulted in significant neurological deficit resulting in paraplegia were sport related. Most of these were diving accidents.

the corresponding occipital condyle. These facets face upwards and medially. On the inferior surface of the lateral mass- es are concave facets which articulate with the superior articular facet of the axis (Fig.1 and 2a).

The axis (C2) provides a pivot by which the head and C1 rotate. This pivoting takes place via the dens, a bony protuberence from the body of the axis. In front of the dens passes a transverse ligament which attaches to the lateral masses of the atlas. At the base of the dens are facets which articulate with the inferior facets of the atlas. Attached to the dens are alar liga- ments which pass laterally and forwards to attach to the lateral mass of the atlas and to the occipital condyles (Fig.2a).

Facts ● In England over 500,000 players take part in rugby union every weekend for eight

months of the year ● In a five year period between 1993 and 1998 reported statistics for cervical spine injury in rugby union for schools and clubs respectively were 5.2% and 8.5% ● The incidence of disabling paraplegia has been five per season from 1992 through to 1995, and two in the season 1995-1996 ● In a recent study, Scher (2) reported that over a 10 year period 1987-1996, 8.7 players received serious cervical spinal cord injury ● Figures recently reported from Argentina show there was on average one tetraple- gia per season over the period 1977–1997, however only 48,000 players participate in rugby in Argentina, less than 10% of those in the UK.

Brachial plexus - upper,

middle and lower trunks

Figure 1: Position of brachial plexus and its rela- tionship with the intervertabral foramen

Occipital-atlas joint (CO–C1) Flexion consists of a posterior glide of the occiput checked by the anterior border of the foramen magnum and dens. Extension is limited by the tectorial membrane. - Flexion of the C0-C1 joint past neutral position leads to tension in the tectorial membrane which then limits C1–C2 flexion - C0–C1 axial rotation is limited by alar ligaments and bony alignment - Lateral flexion involves 5o motion at C0–C1 and also at C1-C2. C0–C1 lateral flexion is controlled by the alar ligaments

C2 – T1 The vertebrae C2–T1 are similar in struc- ture. There are joints between the verte-

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