GGC - MSK Index
Radicular symptoms in the thoracic spine may be divided into radicular pain and radiculopathy.
Thoracic radiculopathy is described as pain, paraesthesia or anaesthesia due to compromise of a spinal nerve root with symptoms presenting in a pattern consistent with the nerve root’s dermatome (Appendix 2) (Sebastian, 2013).
Radiculopathy can occur in the absence of pain and radicular pain can occur in the absence of radiculopathy (Bogduck, 2009). Radiculopathy is not defined by pain, but by objective neurological signs.
The classic pattern of radicular pain or radiculopathy would present with band-like pain radiating from the posterior spinal column to the anterior walls of the thorax and abdomen (O’Connor et al, 2002). The pain may also mimic cardiopulmonary, gastrointestinal or genitourinary disorders (Ozturk et al, 2006; O’Connor et al, 2002).
It is important to note that thoracic radiculopathy is often accompanied with myelopathy. Thoracic myelopathy may include bladder dysfunction, wide-based ataxic gait or upper motor neuron signs (Babinski, clonus & hyper-reflexia). Mild lower limb paraparesis is the most common myelopathic symptom due to a thoracic disc herniation (O’Connor et al, 2002; Ozturk et al, 2006).
Cause
Thoracic disc disease is thought to be the most common cause of thoracic radiculopathy (O’Connor et al, 2002). Herniation is most likely to occur at the lower thoracic levels with T11-T12 representing 26-50% of all thoracic disc herniations. Upper thoracic disc herniations are rare (O’Connor et al, 2002; Kanno et al, 2009).
Other possible causes of thoracic radiculopathy include: degeneration/spondylosis, stenosis, diabetes, Herpes Zoster infection, osteoporosis/compression fractures (usually mid/low thoracic spine), Lyme disease, discitis, osteomyelitis, tumours/metastases, degeneration of posterior spine structures, paraspinous abscesses and arachnoid cysts (Hafsteindottir, 2012; Newman et al, 1995; O’Connor et al, 2002; Sebastian, 2013; Spuck et al, 2006).
Prevalence
Thoracic radiculopathy is a rare disorder with symptomatic disc herniations thought to represent less than 1% of all diagnosed disc herniations with an incidence of 1 per million per year (Hafsteindottir, 2012; Ozturk et al, 2006). A history of trauma is described in 33-50% of symptomatic patients (Ozturk et al, 2006). Surgical treatment of thoracic disc herniations comprises only 0.15 - 4% of all spinal disc surgeries (Krauss et al, 2005). The MRI finding of a thoracic disc herniation does not necessarily indicate the presence of radicular pain/radiculopathy as more than 70% of thoracic disc herniations are asymptomatic (Ozturk et al, 2006).
The incidence of thoracic disc disease is equal between men and women with the onset of symptoms being most common between the third and sixth decades (O’Connor et al, 2002; Ozturk et al, 2006). However, in the case of radiculopathy secondary to diabetes, symptoms usually present in older, non-insulin dependent males (O’Connor et al, 2002).
Presentation
The presentation of thoracic radiculopathy/radicular pain varies from very little to severe pain (Ozturk et al, 2006; Hafsteindottir, 2012; Sebastian, 2013). Typically the pain has a band-like distribution with dermatomal sensory loss and motor weakness with or without myelopathic symptoms. The pain is described as ‘burning’, ‘shooting’, or ‘cutting’ (Ozturk et al, 2006). To assist in the identification of a specific thoracic level the following can be used as a guide.
Pain or sensory disturbance into:
- axilla or anterior chest wall T1/2
- nipple area T4
- xiphoid T6
- umbilicus T10
However, there may not be localisation of pain to a specific dermatome.
