title: Comparison of muscle and joint pressure-pain thresholds in patients with complex regional pain syndrome and upper limb pain of other origin.
abstract: Pain localized in the deep tissues occurs frequently in complex regional pain syndrome (CRPS). In addition, hyperalgesia to blunt pressure over muscles is common in CRPS, but it often appears in limb pain of other origin as well. Considering that 3-phase bone scintigraphy (TPBS) reveals periarticular enhanced bone metabolism in CRPS, joint-associated hyperalgesia to blunt pressure might be a more specific finding than hyperalgesia over muscles. In 34 patients with upper limb pain (18 CRPS, 16 non-CRPS; diagnosed in accordance to the Budapest criteria) and in 18 healthy controls, pressure-pain thresholds (PPT) were assessed bilaterally over the thenar (PPTThenar), the metacarpophalangeal (PPTMCP), and the proximal interphalangeal (PPTPIP) joints using a pressure algometer (Somedic, Sweden). Beforehand, all patients had received TPBS for diagnostic purposes independently of the study. Region-of-interest (ROI) ratios (mineralization phase) for the MCP and PIP, excluding fracture sites, were correlated with the PPT. In CRPS, all ROI ratios were significantly increased and all PPT of the affected hand were decreased compared to non-CRPS (PPTThenar: 243±150kPa vs 358±197kPa, PPTMCP: 80±67kPa vs 159±93kPa, PPTPIP: 80±56kPa vs 184±110kPa; P<.01) and controls (PPTThenar: 478±106kPa, PPTMCP: 254±50kPa, PPTPIP: 275±76kPa; P<.01). A PPTThenar below 293kPa revealed 77% sensitivity but only 63% specificity, whereas a PPTPIP below 102kPa had 82% sensitivity and 94% specificity to identify CRPS. Only in CRPS were PPTMCP and PPTPIP correlated significantly inversely with the ROI ratio (MCP: r=-0.439, PIP: r=-0.447). PPTPIP shows higher specificity for CRPS type I than PPTThenar without loss of sensitivity. Therefore, measurement of joint PPT could be a noninvasive diagnostic tool reflecting increased bone metabolism assessed by TPBS as a sign of bone pathophysiology.
authors: Department of Pain Medicine, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany Sektion Neurologische Schmerzforschung und Therapie, Klinik für Neurologie, Universitätsklinikum Schleswig-Holstein, 24105 Kiel, Germany Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany Institute of Diagnostic Radiology, Interventional Radiology and Nuclear Medicine, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH, Ruhr-University Bochum, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany Center for Biomedicine and Medical Technology Mannheim, Heidelberg University, 68167 Mannheim, Germany.
authors: Tina
authors: T
authors: Mainka
authors: Florian S
authors: FS
authors: Bischoff
authors: Ralf
authors: R
authors: Baron
authors: Elena K
authors: EK
authors: Krumova
authors: Volkmar
authors: V
authors: Nicolas
authors: Werner
authors: W
authors: Pennekamp
authors: Rolf-Detlef
authors: RD
authors: Treede
authors: Jan
authors: J
authors: Vollert
authors: Andrea
authors: A
authors: Westermann
authors: Christoph
authors: C
authors: Maier
mesh_terms: D000328:Adult; D018771:Arthralgia / Q000175:diagnosis* / Q000503:physiopathology; D020918:Complex Regional Pain Syndromes / Q000175:diagnosis* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005260:Female; D006225:Hand / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D063806:Myalgia / Q000175:diagnosis* / Q000503:physiopathology; D010147:Pain Measurement / Q000379:methods*; D017288:Pain Threshold / Q000502:physiology*; D011312:Pressure / Q000009:adverse effects*
keywords: Complex regional pain syndrome (CRPS); Inflammation; Pressure-pain threshold; Quantitative sensory testing; Three-phase bone scintigraphy