BRACHIAL PLEXUS REHABILITATION

activity due to stretch within the muscle (see section 4. Proprioception).

Joint stabilisation is correlated with high muscle stiffness and muscle stiffness is linked to low-load activation of the tonic postural muscle fibres (7). Understanding of this concept is important in the condi- tioning of the cervical muscles, particular- ly following a traumatic ’stinger’ where either pain or nerve injury has inhibited normal muscle activity. Research studies which show the benefit of cervical spine strengthening exercises are limited, partly due to the difficulties of designing safe reliable and accurate equipment. Cybex dynamometry for the cervical spine mus- cles is in its infancy and as yet its appli- cation to the spine has not been deter- mined (3). Jull (9) found that the activa- tion patterns of the deep neck flexors were poorer in whiplash patients compared to controls and that the superficial neck mus- cles assisted in compensating for this reduced muscle function.

Further research (10) found that muscle strength of the anterior cervical flexors were weaker in patients with mechanical neck pain compared to control subjects thus postulating that this was an adaptive response to pain causing reflex inhibition and muscle atrophy. Retraining of the cer- vical spine muscles is a two-stage process: 1. Teaching deep neck flexor muscle activi- ty will assist joint stability (muscles longus colli and capitus, rectus capitus anterior and lateralis) 2. Tensing muscles around a joint increases the stretch sensitivity of the muscle spin- dles thereby increasing the proprioception at the joint (11).

Following a ‘stinger‘ injury it is important that all muscles of the cervical spine are

thoracic spine must include the biomechan- ical links in the upper limb. These would emphasise scapula stabilisation with the emphasis on precision and control. Therefore when retraining the cervical spine muscles using a ball, the position and sta- bility of the scapula can be observed and corrected from observation behind the play- er (Fig.4).

Figure 3a: Photograph demonstrating the use of the pressure biofeedback unit to help retrain the deep neck flexor muscles

Following a ‘stinger’ injury if a player suf- fers significant neurological deficit eg. C5,6,7 nerve roots the muscles of the rota- tor cuff might well be affected leading to possible loss of stability of the gleno- humeral joint and the risk of dislocation of the joint.

Figure 3b: Photograph demonstrating retraining of the shoulder abductors with the biofeedback unit attached to the neck muscles to ensure correct sta- bilisation of the cervical spine

tested for activation and facilitation post- injury to ensure the spine is stable during activity.

Retraining of the deep neck flexors can be carried out using the pressure biofeedback unit (Figs.3a+b). To ensure the correct mus- cles are being facilitated a biofeedback unit can be attached to the cervical spine while the muscles are being retrained.

Once the player has mastered this stabilis- ing concept, more specific isometric and dynamic muscle strengthening can be com- menced. Isometric and dynamic neck strengthening can be gained by training with a small ball or using a ‘theraband‘ (Fig.4). It is important to note that strengthening to stabilise in the cervico-

As a progression of the strengthening pro- gramme the muscles of the rotator cuff can be strengthened using dumbell weights while the deep neck flexor muscles are acti- vated using either the pressure biofeedback unit or the small ball (Fig.5). This will allow functional strengthening of the biomechan- ical chain with the cervical spine in a sta- ble position.

At this stage of the programme the player would be expected to have normal neural tissue mobility as this is important in the positioning of the arm in various sports. Most collision sports demand a strong neck musculature. Strengthening of the neck muscles is an important part of their phys- ical conditioning. In American football a guide of ‘satisfactory neck strength’ before return to play is for the player to support his body weight on his cervical spine at an angle of 45 degrees (12). In Rugby union there are no reliable standardised guide- lines on cervical muscle strength before return to play following a ‘stinger‘ injury. However one would expect a player to have full range of neck movement and full mus- cle power with no neurological deficits.

Figure 4: Photograph demonstrating neck strength- ening with a ball and observation of scapula stabil- isation from behind

Figure 5: Strengthening of the rotator cuff muscles using dumbells with the ball used to isometrically stabilise the cervical spine.

Children Special consideration must be used for chil- dren who play contact collision sports. Although they might not receive as many ‘stinger’ injuries as the adult sportsman, when rehabilitating a child’s cervical spine post-injury it is important to realise that their joints are developing through adoles- cence. Controversy reigns regarding the benefits of weight training in children due to lack of circulating androgens. Before puberty, serum testosterone levels are insufficient to produce significant strength

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