2 Der viszeral assoziierte Schulterschmerz - Osteopathic Research

Viscerally Associated Shoulder Pain
Subjective Perspectives and Diagnostic Procedures – the Osteopathic Point of View
enterotome. The neural tube, which also establishes a segmental relationship with
the mesodermal myotome and sclerotome, is part of the metameric differentiation
process. Although individual parts of a segment are displaced during the
embryological development process, they remain related throughout life by the same
spinal nerve. This explains the interrelationship between the surface and the inside of
the body and helps us to understand how disease may spread from an organ to the
skin, the muscles or the bones within the corresponding segments (cf. Wancura-
Kampik 2010).
The second model that explains referred pain is based on the convergence of
somatic and visceral afferents. It is thought that afferent neurons from the skin and
visceral afferents from the organs converge via the dorsal root of the spinal cord to
the same transmitting neurons (cf. Trepel 2008; Speckmann et al. 2008;
Giamberardino 2003). Since the viscero-afferent and somato-afferent impulses blend,
it is impossible to precisely allocate the origin of the pain and its perception.
Consequently, the input from visceral fibres is interpreted as coming from the somatic
tissue (cf. Trepel 2008; Schünke et al. 2006). This fact has a considerable impact on
pain sensation since on the one hand, the brain does not seem to be capable, in
certain cases, to localize precisely the origin of the disease and on the other,
misinterpretations may occur. A pain may be triggered by a visceral organ, but the
nociceptive system refers the pain to the shoulder-arm area, an extremity or the
abdominal wall (cf. Egle et al. 1999, Speckmann et al. 2008). For example, spinovisceral
afferents of the heart excite the coronary vessels when the vascularisation is
reduced, e.g. in the case of ischemia of the myocardium, these afferents reaching the
upper thoracic segments of the spinal cord. Somatic afferents from the left shoulderarm
area end in the same segment. “The convergence of spinal neurons makes the
information transferred to the CNS less precise, the stimulation of the cardiac
afferents being referred to the shoulder-arm region as pain” (Speckmann et al.
2008:73).
Referred pain triggered by direct pressure represents the third model. A very
important nerve leaving the spinal cord at the segments C3 – C5, is the phrenic nerve
(cf. Trepel 2008; Hebgen 2009). The phrenic nerve is responsible for the sensory
innervation of the liver capsule, the diaphragm and the gall bladder, etc. (cf. Hebgen
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