Predictive Value of Sympathetic Skin Response in Diagnosing Complex Regional Pain Syndrome: A Case-Control Study

Abstract

ObjectiveTo investigate the predictive value of the sympathetic skin response (SSR) in diagnosing complex regional pain syndrome (CRPS) by comparing three diagnostic modalities-SSR, three-phasic bone scans (TPBS), and thermography.MethodsThirteen patients with severe limb pain were recruited. Among them, 6 were diagnosed with CRPS according to the proposed revised CRPS clinical diagnostic criteria described by the International Association for the Study of Pain. SSR was measured in either the hands or feet bilaterally and was considered abnormal when the latency was prolonged. A positive TPBS finding was defined as diffuse increased tracer uptake on the delayed image. Thermographic findings were considered positive if a temperature asymmetry greater than 1.00℃ was detected between the extremities.ResultsFive of 6 CRPS patients showed prolonged latency on SSR (83% sensitivity). TPBS was positive in the 5 CRPS patients who underwent TPBS (100% sensitivity). Thermography was positive in 4 of 5 CRPS patients who underwent the procedure (80% sensitivity). The remaining 7 non-CRPS patients differed on examination. SSR latencies within normal limit were noted in 4 of 7 non-CRPS patients (57% specificity). Results were negative in 4 of 5 non-CRPS patients who underwent TPBS (80% specificity), and negative in 3 of 5 non-CRPS patients who underwent thermography (60% specificity).ConclusionSSR may be helpful in detecting CRPS.

Usefulness of bone scintigraphy for the diagnosis of Complex Regional Pain Syndrome 1: A systematic review and Bayesian meta-analysis

“…[ 46 ] The sample size ranged from 13 to 145 patients ( Table 1 ), mean age from 35 to 63 years, and the average disease duration from 6 to 103 weeks. The reference standard for the diagnosis of CRPS was in three studies the clinical Budapest criteria, [ 29 , 44 , 45 ] four studies the IASP criteria, [ 34 , 42 , 43 , 47 ] and in five studies the Kozin diagnostic criteria. [ 40 , 41 , 46 , 48 , 49 ] Seven studies [ 30 – 32 , 36 – 38 ] did not report on the diagnostic criteria used for the diagnosis of CRPS 1 and two studies [ 33 , 39 ] used other clinical criteria In total 13 studies were included in the analysis of the influence of patient characteristics on the proportion of positive bone scans.…”

<p>Evaluation of the Sympathetic Skin Response in Men with Chronic Prostatitis: A Case-Control Study</p>

“…14 , 15 Additionally, patients with CP type IIIb may experience sudomotor disturbances, such as hyperhidrosis or hypohidrosis. 16 , 17 …”

“…Following an emotional or stress stimulus, changes in the sudomotor activity mediated by the sympathetic nervous system alter the skin’s resistance to an electrical current. 17 …”

“…While SSR latencies within normal limit were noted in 4 of 7 non-CRPS patients (57% specificity), it was concluded that SSR might help detect CRPS, which is consistent with the present research. 17 …”

A Child Patient Followed-up with the Diagnosis of Recurrent Complex Regional Pain Syndrome

“…The definite prevalence of CRPS is unknown. The reported prevalence rates of CRPS in predisposing medical conditions are as follows: 5-20% in coronary artery disease, 12-21% in hemiplegia, 0.2-35% in colles fracture, 3% in peripheral nerve injury, 1-2% in bone fractures, and 0.5% in other traumatic injuries (4)(5)(6)(7)(8). The therapy of CRPS is quite difficult, where the first step should be to take measures to decrease the risk in medical conditions triggering CRPS (4-6).…”