Talk: A New Plantar Tender Point in Fibromyalgia: A Worthy Candidate for the ACR Classification Criteria? (2009 ACR/ARHP Annual Scientific Meeting)

Monday, October 19, 2009: 9:00 AM - 11:00 AM

Hall D (Pennsylvania Convention Center)

A. Spindler¹, W. Spindler¹, V. Bellomio¹, A. Berman¹, E. Lucero¹, H. Berman¹, R. Sueldo¹, L. Gonzalez¹, M.V Gandur¹, M. Guardia¹, A.L Barbaglia¹, M. Santana², C. Waimann³, K. Kyrmair³, R. Chaparro del Moral⁴, O. Rillo⁵ and J. Moreno⁶, ¹Hospital Padilla, Tucuman, Argentina, ²Facultad de Medicina, Tucuman, Argentina, ³IREP, Buenos Aires, Argentina, ⁴Hospital Tornu, Buenos Aires, Argentina, ⁵Hospital Tornu, ⁶CER, San Juan

Presentation Number: 1118

Poster Board Number: 469

Purpose: Fibromyalgia (FM) is a complex, chronic condition which causes widespread pain accompanied by tenderness at 11 or more of 18 predetermined tender point sites, ACR Classification Criteria (1990 FMACRCC). Because 10 of these sites are in the neck and shoulder areas, which are major target areas for rheumatic and musculoskeletal conditions, diagnostic dilemmas often arise. Because of this reason reproducible tender points placed elsewhere would be advantageous in diagnosis of FM. The objective of this study was to assess sensitivity and specificity of a tender point placed infero-medially in the distal third of the longitudinal plantar arch in FM patients and controls

Method: A multicenter study was carried out in consecutive patients with FM (1990 FMACRCC) and concurrent healthy controls matched by sex and age (± 3 years). The proposed site, the accepted ACR sites (pairs) and control sites (pairs) biceps, quadriceps, and external aspect of the foot were evaluated by digital pressure averaging 4 kg/cm² exerted by a previous trained rheumatologist. Sensitivity and specificity of the new, the ACR accepted and the control tender points were compared by unpaired t-test and the McNemar test.

Results: : There was a total of 55 FM female patients with an average age of 47 ± 9.8 years. Healthy controls comprised 48 females with a similar age distribution (44 ± 11 years). The new plantar site was tender in 48/55 FM patients (87%) vs. 2/48 controls (4%) giving a sensitivity of 87%, specificity of 96%, positive LR of 20.9 (CI 95%=6.2-76.1) and negative LR of 0.13 (CI 95%=0.06-0.25). Some of the ACR tender sites had lower sensitivity and specificity than the new plantar site i.e, occiput was tender in 15% of controls (sensitivity 71%, specificity 85%), trapezius was positive in 33% of controls (sensitivity 87%, specificity 67%) and low cervical was positive in 35% of controls (sensitivity 78%, specificity 65%).Control sites were negative in 34/48 (71%) FM patients with the plantar site positive. The plantar site had good concordance in FM patients with tender sites such as the lateral epicondyle (73%) and the occiput (65%)

Conclusion: Our findings indicate that a tender site located infero-medially in the distal third of the longitudinal plantar arch has a high sensitivity and specificity in patients with FM as defined by the FMACRCC. Furthermore, it had a greater specificity than cephalad sites such as occiput, trapezium and low cervical sites. Further investigations on this novel site appear warranted.

Keywords: fibromyalgia

Disclosure: A. Spindler, None; W. Spindler, None; V. Bellomio, None; A. Berman, None; E. Lucero, None; H. Berman, None; R. Sueldo, None; L. Gonzalez, None; M. V. Gandur, None; M. Guardia, None; A. L. Barbaglia, None; M. Santana, None; C. Waimann, None; K. Kyrmair, None; R. Chaparro del Moral, None; O. Rillo, None; J. Moreno, None.

1118 - A New Plantar Tender Point in Fibromyalgia: A Worthy Candidate for the ACR Classification Criteria?