The basic aim of rehabilitation of upper extremity function in subjects with tetraplegia is to provide them with as much autonomy as possible. A strong focus is put on the ability to perform activities of daily living such as dressing/undressing, personal hygiene, eating or performing transfers independent from caregivers. In this context, training is based on two fundamental principles, namely, restoration or compensation.

Assuming that an SCI leads to the loss of skilled motor behaviour, recovery or restoration would depend on the reacquisition of elemental motor patterns by motor learning or, in the absence of reacquisition, adaptation of remaining (compensation) or integration of alternative (substitution) motor elements. The term recovery of motor performance is defined as the restoration of elemental motor patterns present prior to central nervous system (CNS) injury [32]. Motor compensation is defined as the appearance of new motor patterns resulting from the adaptation of remaining motor elements or substitution, meaning that functions are taken over, replaced or substituted by technical aids or assistive devices.

There is still a lack of consensus on the definition of “functional recovery”. This term is often used without distinguishing whether the “recovery” is occurring at the body function/structure or the activity level. Thus, there is often no consensus about whether “recovery” is because of true motor recovery or compensation at each of these levels.

The International Classification of Functioning, Disability and Health (ICF [53, 54]), published by the WHO in 2001, provides a standard language and framework for the description of health and health-related states independent from specific diseases. Functioning and disability are viewed as a complex interaction between the health condition of the individual and the contextual factors of the environment as well as personal factors. The ICF is based on a biopsychosocial model and provides a coherent view of different perspectives of health: biological, individual and social. It is structured around the following broad constructs:

In an attempt to improve knowledge exchange between fundamental researchers, clinical researchers and clinicians, a definition of recovery and compensation at three different levels of the ICF, at which each may occur, has been proposed (Table 22.1).

A way of distinguishing between recovery and compensation is to look on how the movement is performed (body function/structure level) and on the movement outcome (activity level). At the body function/structure level, the emphasis is on the quality of movement regardless of movement outcome or task accomplishment. Recovery at this level is characterised by the reappearance of pre-injury movement patterns during task accomplishment. True motor recovery at this level, therefore, could be characterised, for example, by a decrease in spasticity or by a reduction in trunk displacement during a reaching or pointing movement. Adaptive compensation at this level would be characterised by the appearance of alternative movement patterns during the accomplishment of a task. Substitutive compensation would reflect the use of different effectors to replace lost motor elements. It should be recognised that both adaptive and substitutive compensation may occur in various combinations at the performance level. An example of adaptive compensation is the use of excessive shoulder abduction when the range of active elbow extension is decreased. At the level of the wrist and hand, alternative grasping strategies such as anchoring the fingers on the object to achieve a passive grasp can compensate for the lack of active finger flexion.

Recovery at the activity level requires that the task is performed using the same end effectors and joints in the same movement patterns typically used by able-bodied individuals. In contrast, compensation at this level often takes the form of substitution and would be noted if the patients were able to accomplish the task using assistive devices.

The question of course arises, when to apply a restorative therapy approach and when to move to a compensatory training or vice versa? There is no general answer to these questions, and the separation of compensatory from restorative therapies is often difficult or even impossible. As a general rule, in the first 3 to 6 months after the injury, where the potential for neurological recovery is highest, the focus of rehabilitation specialists is on transferring neurological recovery into functional improvements by application of restorative therapy approaches. However, in parallel in some patients, compensatory movements or substitutive technical aids may be encouraged from the very beginning to maximise functional ability. This is in particular true for patients with severe impairment, poor prognosis and likely low benefit from restorative therapies. Of course, if unexpectedly a patient recovers a substantial amount of sensory or/and motor functions, restorative therapies may be applied at any stage. At the point in time, when only little neurological recovery occurs and the time of admission into the home environment comes close, the more compensatory therapies are in the focus to achieve the highest level of functional ability as a prerequisite for leading an independent life at home.

It is important to emphasise that compensation and recovery are not mutually exclusive. Instead, functional recovery is often dependent upon compensation, and compensatory approaches might enable new possibilities for restorative trainings, e.g. a hand stabilisation orthosis or a grasp neuroprosthesis may allow for retraining shoulder and elbow movements. Because there is no general rule for focusing on compensation or restoration, it is important to know the patient’s individual priorities and her or his social environment. Taking them into account is mandatory to agree upon realistic rehabilitative goals and to work with the appropriate therapy methods to achieve them.

A complete SCI (AIS A) is defined by the absence of motor and sensory functions in the most caudal segments S4/S5 [21]. However, in reality this means that in most of the patients with complete cervical SCI, there is only a limited zone of partial preservation of one or two segments below the neurological and/or motor level of injury.

For patients with cervical SCI a shift of the motor level of only one segment caudally can result in a tremendous improvement in independence. Taking additional factors like age, pre-injury comorbidities and diseases or cultural background not into account, general rehabilitative goals can be defined in respect to the motor level (Fig. 22.2). The initial setting of goals is important to bundle all rehabilitative efforts and for communication to the patient.

In the absence of the possibility for reacquisition of pre-injury motor behaviours in very severely impaired individuals or at the chronic stage of injury, adaptation of remaining (compensation) or integration of alternative (substitution) motor elements are considered as the primary therapeutic approach. The main common compensatory strategies in persons with cervical SCI are the establishment of a passive or active tenodesis grip [14] and provision of dedicated tools and adaptation of the environment to enhance independence in everyday activities.

A recent review on the effectiveness of restorative therapies came to the conclusion that training including exercise therapy and (functional) electrical stimulation of the upper limb following cervical SCI leads to improvements in muscle strength, upper-limb function and activity of daily living resulting in a better quality of life [33]. Some studies in the literature indicate that early initiation of SCI-specific rehabilitation is extremely important. A delay in starting these interventions may negatively influence ultimate functional capability [22, 43]. On the other hand, this does not mean that training initiated in the chronic stage does not result in improvements of muscle strength, of upper extremity function and consequently of activities of daily living or quality of life, but the effects are most probably smaller. Therapeutic exercises may have different aims in patients with tetraplegia, among them training of muscular strength and endurance, relaxation of muscles with increased muscle tone, reduction of upper-limb edema, maintenance of joint mobility and flexibility by moving limbs in their entire range of movement and improvement of coordination and fine motor skills by task-specific, goal-oriented, high-intensity training regimes.