Beweging van een zenuw in de arm tijdens nek-bewegingen bij patiënten met een nekhernia en bij gezonde proefpersonen

Cervical radiculopathy (CR) is a clinical
condition whereby motor, reflex and/or sensory
changes (such as paraesthesiae or numbness) can
present, often provoked by neck posture(s) and/or
movement(s) (Kuijper et al. 2009, Thoomes et al.
2012) . Radiculopathy is differentiated from radicular
pain, where radiculopathy is a neurological state in
which conduction is impaired along a spinal nerve or
its roots (Merskey H 1994, Bogduk 2009, Bogduk
2011, Smart et al. 2012) . Although radiculopathy and
radicular pain commonly occur together,
radiculopathy is not defined by pain alone but also by
neurological signs (Bogduk 2009, Bogduk 2011) .

Sparse epidemiological data for CR reports an
age-corrected incidence of 83.2 per 100.000 persons
(107.3 for males en 63.5 for females) with a peak
incidence at 50-59 years (Radhakrishnan et al. 1994).
Another study reported a prevalence of 3.5 per 1000
people and a peak annual incidence of 2.1 cases per
1000 people (Salemi et al. 1996) .

The most often reported cause of CR is
compression of the nerve root in the interforaminal
space, most commonly due to either loss of height of
the disc or degenerative spondylotic changes or both
(Radhakrishnan et al. 1994) . Other causes like
tumors, infections or avulsion fractures are rare
(Radhakrishnan et al. 1994) . A recent study
examining the prevalence of cervical nerve root
compression, as seen with Magnetic Resonance
Imaging (MRI) in 78 patients with acute onset CR,
reported compression due to a herniated cervical
intervertebral disc in 35-41%, foraminal spondylotic
changes in 22-36% and a combination of both in 10-
28% of cases (Kuijper et al. 2011) . The C6 (66%) and
C7 (62%) nerve roots are most often afflicted (Kim et
al. 2016) .

Little is known about the natural course of CR.
A recent systematic review on CR due to disc
compression reported a substantial improvement in
the first 4 to 6 months and a time to complete
recovery ranging from 24 to 36 months in
approximately 83% of patients (Wong et al. 2014) .

Conservative management is preferred above
surgery, as surgery is not superior and the risk benefit
ratio seems to be less preferable (Nikolaidis et al.
2010, Peolsson et al. 2013) . Also, some 29% of
surgically managed patients with CR are rescheduled
for surgery of an adjacent level within one year (Bono
et al. 2011, van Middelkoop et al. 2013) . Several
reviews assessed the effectiveness of conservative
management in patients with CR (Bono et al. 2011,
Salt et al. 2011, Thoomes et al. 2013) . There is low
level evidence for the effectiveness of conservative
management for the level of pain for multimodal
interventions with a neurodynamic intent (including
neurodynamic mobilization (NM)), combined with joint
and muscle mobilizations (Basson et al. 2015,
Thoomes 2016, Ballestero-Perez et al. 2017, Basson
et al. 2017) .

Hypotheses about the working mechanisms of
NM have evolved. From the inception in the early
1960’s, a biomechanical model was most prevalent
(Breig 1960, Butler 1991, Kleinrensink et al. 1995,
Kleinrensink et al. 2000, Shacklock 2005, Coppieters
and Butler 2008, Coppieters et al. 2009) . NM was
thought to improve nerve movement and/or other
biomechanical properties such as strain, stiffness etc.,
resulting in the use of “nerve stretching exercises”
until well in the early 2000’ (Jepsen and Thomsen
2008) . Recently theoretical models concerning the
underlying mechanisms of NM have moved to include
restoration of homeostasis in and around the nerve
and reducing intraneural edema through intraneural
fluid dispersion in the nerve root and axon (Gilbert et
al. 2015, Gilbert et al. 2015, Basson et al. 2017,
Boudier-Reveret et al. 2017) . For example, theories
regarding fluid dispersion rely on the thixotrophic
properties of nerve movement against its mechanical
interface. Therefore, the improved fluid mechanics are
dependent on nerve movement (Brown et al. 2011,
Gilbert et al. 2015, Boudier-Reveret et al. 2017) .

Ultrasound imaging (USI) is increasingly being
used by healthcare practitioners in the assessment of
movement dysfunctions (Plagou et al. 2016) . It is also
gaining popularity as a tool for assessing nerve
excursion and is becoming an important tool for the
assessment during conservative management of
entrapment neuropathies (Kasehagen et al. 2018) .
Several researchers have assessed longitudinal and
transverse excursion of peripheral nerves using USI,
in asymptomatic subjects and also in patients with
carpal tunnel syndrome (Nee et al. 2010, Coppieters
et al. 2015, Meng et al. 2015, Ridehalgh et al. 2015,
Kasehagen et al. 2016, Ellis et al. 2017, Kasehagen
et al. 2018) .

A segmental contra-lateral cervical lateral glide
(CCLG) mobilization technique of the cervical spine
has shown to be effective in patients with nerve-
related neck and arm pain (Coppieters et al. 2003,
Basson et al. 2017) . The CCLG mobilization
technique is part of a contemporary evidence based
conservative treatment regime in patients with CR,
which also includes active and passive exercises
aimed at restoring optimal neuromusculoskeletal
mobility as well as local and global muscular control
and endurance of the cervical and thoracic spine
(Leininger et al. 2011, Salt et al. 2011, Thoomes et al.
2013, Thoomes 2016, Kjaer et al. 2017) . The
neurodynamic intent in this technique is to mobilize
the nerve in relation to non-neural structures
surrounding the nerve root (e.g. muscle, tendon,
fascia and bone: i.e. the “mechanical interface”) (Hall
and Elvey 1999, Tillett et al. 2004) .

It has been shown that a CCLG technique will
result in median nerve excursions in both the wrist
and the elbow in healthy individuals (Brochwicz et al.
2013) . Similar longitudinal median nerve excursions in
the wrist have been documented during inspiration
and cervical side flexion (Dilley et al. 2003, Greening
et al. 2005) . To date, longitudinal nerve excursions
during a CCLG have not been assessed in patients
with CR. It would be of interest to assess if there is a
difference in median nerve movement between patients and healthy individuals.
Furthermore, if nerve excursion are diminished in
patients with CR, it would be if interest to establish if
nerve excursions change in response to conservative
treatments, such as NM, as the symptoms of CR
decrease. To our knowledge this has also not yet
been assessed previously and this information could
potentially assist in a choice of therapeutic
intervention.

We hypothesize that peripheral nerve
excursions are not significantly diminished in patients
with CR compared to healthy controls. This would
assist in lending more credibility to underpinning
therapeutic efficacy of the CCLG through diminishing
intraneural edema and restoring local neural
homeostasis of the nerve root (Gilbert et al. 2015,
Gilbert et al. 2015, Basson et al. 2017, Boudier-
Reveret et al. 2017) .

Therefore the aim of this study is to assess
longitudinal excursions of the median nerve in asymptomatic
subjects and patients with CR during a mechanically
induced CCLG movement of the cervical spine. A
secondary aim is to reassess this at a 3 month follow-
up in patients with CR and correlate this with the
progression of signs and symptoms.

During a contra-lateral cervical lateral glide
mobilization technique, the median nerve
longitudinally moves at the sites of the elbow
and/or the wrist and there is a notable difference
between patients and healthy controls.

T0: intake

T1: 12 weeks

A contra-lateral cervical lateral glide (CCLG)
mobilisation technique will be performed by a
computerized treatment plinth; the Occiflex.
during this CCLG, the longitudinal excursions of
the median nerve will be assessed at the wrist and elbow , using ultrasound imaging (USI).