Complex regional pain syndrome of upper limbs after stroke is frequently called shoulder-hand syndrome (SHS). Complex regional pain syndrome is neuropathic pain disorders that develop as an exaggerated response to a traumatic lesion or nerve damage or as the consequence of a distant process such as a stroke, spinal lesion or myocardial infarction.
However, sometimes it may appear without an apparent cause.
The onset and severity of shoulder-hand syndrome appear to be related with the cause of the stroke, the severity, and recovery of motor deficit, spasticity, and sensory disturbances.
Another important aetiological factor is glenohumeral subluxation. The physiopathology of the disease is still not known.
In CRPS, there is an exaggerated inflammatory response and some chemical mediators have been identified and are present in the inflammatory soup around the primary afferent fibers that, through different processes, can induce hyperexcitability of the afferent fibers. It is hypothesized that a localized neurogenic inflammation is at the basis of edema, vasodilation, and hyperhidrosis that is present in the initial phases of CRPS. The repeated discharge of the C fibers causes an increased medullary excitability (central sensitization). Another important factor is the reorganization of the central nervous system, and in particular, this appears to affect the primary somatosensory cortex
Diagnosis of Shoulder Hand Syndrome
There would be a history of stroke and the paretic upper arm frequently appears painful, swollen, with altered heat and tactile sensations and slightly dystrophic skin within a non-use syndrome.
Diagnosis is clinical and there are no specific tests, nor pathognomic symptoms to identify this disease with certainty.
Imaging in Shoulder Hand Syndrome
Imaging is noncontributory. However, some investigations can aid differential diagnosis with other diseases.
Treatment of Shoulder Hand Syndrome
Treatment may be consists of psychotherapy, regional anesthesia, neuromodulation, and sympathectomy.
A variety of drugs are used to treat shoulder hand syndrome which includes antidepressants, anti-inflammatory drugs, vasodilators, GABA analogs such as gabapentin and pregabalin, and alpha- or beta-blockers, and opioid analgesics.
The key to effective treatment undoubtedly lies in an expert multidisciplinary team.