Anders Jespersen

Computerized cuff pressure algometry: a new method to assess deep-tissue hypersensitivity in fibromyalgia

Abstract The aim of this study was to evaluate the use of computerized cuff pressure algometry (CPA) in fibromyalgia (FM) and to correlate deep‐tissue sensitivity assessed by CPA with other disease markers of FM. Forty‐eight women with FM and 16 healthy age‐matched women were included. A computer‐controlled, pneumatic tourniquet cuff was placed over the gastrocnemius muscle. The cuff was inflated, and the subject rated the pain intensity continuously on an electronic Visual Analogue Scale (VAS). The subject stopped the inflation at the pressure‐pain tolerance and the corresponding VAS‐score was determined (pressure‐pain limit). The pressure at which VAS firstly exceeded 0 was defined as the pressure‐pain threshold. Other disease markers (FM only): Isokinetic knee muscle strength, tenderpoint‐count, myalgic score, Beck Depression Inventory, and Fibromyalgia Impact Questionnaire. Student’s T‐test was used to compare pressure‐pain threshold and pressure‐pain tolerance and the Mann–Whitney test to compare pressure‐pain limit. Pearson’s correlation was used to detect linear relationships. Pressure‐pain threshold and pressure‐pain tolerance assessed by CPA were significantly lower in FM compared to healthy controls. There was no difference in pressure‐pain limit. CPA‐parameters were significantly correlated to isokinetic muscle strength where more hypersensitivity resulted in lower strength. Pressure‐pain threshold and pressure‐pain tolerance assessed by CPA were significantly lower in patients with FM indicating muscle hyperalgesia. CPA was associated with knee muscle strength but not with measures thought to be influenced by psychological distress and mood.

Self-reported somatosensory symptoms of neuropathic pain in fibromyalgia and chronic widespread pain correlate with tender point count and pressure-pain thresholds

&NA; Widespread pain and pain hypersensitivity are the hallmark of fibromyalgia, a complex pain condition linked to central sensitization. In this study the painDETECT questionnaire (PDQ), validated to identify neuropathic pain and based on pain quality items, was applied in a cross‐sectional sample of patients with chronic widespread pain (CWP). The aims of the study were to assess the patient‐reported sensory neuropathic symptoms by PDQ and to correlate these with tender point (TP) count and pressure‐pain thresholds. Eighty‐one patients (75 F, 6 M) with CWP (ACR‐criteria) filled in the PDQ. Manual TP examination was conducted according to ACR guidelines. Computerized cuff pressure algometry was used for the assessment of pressure‐pain detection thresholds (PDT, unit: kPa) and pressure‐pain tolerance thresholds (PTT, unit: kPa). Mean TP count was 14.32 (range: 2–18), mean PDQ score 22.75 (range: 5–37). Mean PDT was 8.8 kPa (range: 2–36) and mean PTT 30.9 kPa (range: 4–85). Deep‐tissue hyperalgesia was the predominant somatosensory symptom reported in 83%, but other neuropathic symptoms were also frequent, e.g. burning 51% and prickling 47%. Statistically significant correlations were found between PDQ score and TP count: r = 0.35 (p < 0.01), and PDQ score and PDT: r = 0.45 (p < 0.01), and PTT: r = 0.43 (p < 0.01). The study indicates that pain in CWP has neuropathic features, and that the presence and number of tender points are associated with neuropathic pain symptoms. A high mean PDQ score was found to correlate with TP count and pressure‐pain thresholds. The PDQ may become a useful tool assisting in the identification of central sensitization in patients with CWP and in the future diagnostic assessment fibromyalgia.

Relationships between the fibromyalgia impact questionnaire, tender point count, and muscle strength in female patients with fibromyalgia: A cohort study

OBJECTIVE To test the hypothesis that fibromyalgia (FM) patients with reduced lower extremity strength are more symptomatic and tender than FM patients with normal muscle strength. METHODS A total of 840 FM patients and 122 healthy subjects were evaluated between 1998 and 2005. All of the patients completed version 1 of the Fibromyalgia Impact Questionnaire (FIQ) and were assessed for tender points and knee muscle strength. All subjects underwent bilateral isokinetic knee muscle strength testing in flexion and extension. Normative knee muscle strength values were calculated from the healthy subjects, and the FM cohort was divided in 2 groups: 1) patients with normal muscle strength and 2) patients with low muscle strength (2 SDs below normal). The clinical characteristics of these 2 groups were compared. RESULTS Significantly reduced knee muscle strength was found in 52% of the patients. There were no clinically significant differences between patients with low versus normal muscle strength. There were no clinically significant correlations between total FIQ score, tender point count, and muscle strength. Only 4.6% of the FIQ scores and 5.1% of the tender point counts were explained by muscle strength. CONCLUSION Significantly reduced knee muscle strength was found in more than half of the patients. Patients with subnormal muscle strength were not more symptomatic or tender than patients with normal muscle strength. There were no clinically significant correlations between FIQ, tender point count, and muscle strength; therefore, reduced knee muscle strength appears to be a common objective abnormality in FM that is independent of measurements of disease activity. The implication of this finding in regard to the clinical assessment of FM needs further study.

Observation-based assessment of functional ability in patients with chronic widespread pain: A cross-sectional study

Summary Evaluated with the Assessment of Motor and Process Skills (AMPS), functional disability in women with chronic widespread pain is substantial and places the individual at risk of need of support for community living. ABSTRACT Knowledge about functional ability, including activities of daily living (ADL), in patients with chronic widespread pain (CWP) and fibromyalgia (FMS) is largely based on self‐report. The purpose of this study was to assess functional ability by using standardised, observation‐based assessment of ADL performance and to examine the relationship between self‐reported and observation‐based measures of disability. A total of 257 women with CWP, 199 (77%) fulfilling the American College of Rheumatology tender point criteria for FMS, were evaluated with the Assessment of Motor and Process Skills (AMPS), an observation‐based assessment providing linear measures of ADL motor and ADL process skill ability (unit: logits). A cutoff for effortless and independent ADL task performance is set at 2.0 for the motor scale and 1.0 for the process scale. A total of 248 (96.5%) had ability measures below the 2.00 ADL motor cutoff and 107 (41.6%) below the 1.00 ADL process cutoff, indicating increased effort and/or inefficiency during task performance as well as a potential need of assistance for community living. Mean ADL motor ability measure was 1.07 and was significantly lower in patients diagnosed with FMS than plain CWP (1.02 vs 1.27 logits, P = .001). Mean ADL process ability measure was 1.09 logits and was without difference between FMS and plain CWP (1.07 vs 1.16 logits, P = .064). Only weak to moderate correlations between self‐reported functional ability and observation‐based AMPS ability measures were observed. The results of the study support the notion of considerable performance difficulties in women with CWP. The everyday life problems are substantial and place the individual at risk of need of support for community living.

Assessment of Pressure-Pain Thresholds and Central Sensitization of Pain in Lateral Epicondylalgia

OBJECTIVE.: To assess pain sensitivity and spreading hyperalgesia in lateral epicondylalgia (LE). SUBJECTS.: Twenty-two women with LE, and 38 controls were included. OUTCOME MEASURES.: Computerized cuff pressure algometry was used for assessment of pressure-pain threshold and tolerance. The stimulus was applied using a single (stimulation-area: 241 cm(2) ) or double-chambered (stimulation-area: 482 cm(2) ) tourniquet on the arm and leg. Spatial summation was expressed as the ratio between pressure-pain thresholds to single and double cuff-chamber stimulation. During 10-minute constant pressure stimulation at intensity relative to the individual pain threshold, the pain intensity was continuously recorded using an electronic visual analogue scale (VAS), and from this the degree of temporal summation was estimated. For LE, a Doppler ultrasound examination of the elbow was made to identify inflammation. RESULTS.: In LE compared with controls the pressure-pain threshold and tolerance were on average reduced by respectively 31% (nonsignificant) and 18% (nonsignificant) on the lower arm and by 32% (P < 0.05) and 22% (P < 0.05) on the lower leg (spreading sensitization). Within the LE group, pressure-pain thresholds were on average reduced by 20% (P < 0.05) and pain tolerance by 10% (nonsignificant) on the painful compared with the asymptomatic side. Spatial summation (P < 0.01) and temporal summation (P < 0.05) was facilitated in LE compared with controls. In LE patients without signs of peripheral inflammation assessed by Doppler ultrasound, temporal summation was significantly stronger than in patients with ongoing inflammation (P < 0.01). CONCLUSION.: Patients with LE may be subgrouped based on pain hypersensitivity and Doppler ultrasound into clinically meaningful subgroups with varying duration of symptoms and different degrees of central sensitization. These groups may require different pain management strategies.

Pain Sensitisation in Women with Active Rheumatoid Arthritis: A Comparative Cross-Sectional Study

Objectives. In some rheumatoid arthritis (RA) patients, joint pain persists without signs of inflammation. This indicates that central pain sensitisation may play a role in the generation of chronic pain in a subgroup of RA. Our aim was to assess the degree of peripheral and central pain sensitisation in women with active RA compared to healthy controls (HC). Methods. 38 women with active RA (DAS28 > 2.6) and 38 female HC were included in, and completed, the study. Exclusion criteria were polyneuropathy, pregnancy, and no Danish language. Cuff Pressure Algometry measurements were carried out on the dominant lower leg. Pain threshold, pain tolerance, and pain sensitivity during tonic painful stimulation were recorded. Results. Women with active RA had significantly lower pain threshold (p < 0.01) and pain tolerance (p < 0.01) than HC. The mean temporal summation- (TS-) index in RA patients was 0.98 (SEM: 0.09) and 0.71 (SEM: 0.04) in HC (p < 0.01). Conclusion. Patients with active RA showed decreased pressure-pain threshold compared to HC. In addition, temporal summation of pressure-pain was increased, indicating central pain sensitization, at least in some patients. Defining this subgroup of patients may be of importance when considering treatment strategies.

The Relationship between Mechanical Hyperalgesia Assessed by Manual Tender Point Examination and Disease Severity in Patients with Chronic Widespread Pain: A Cross-Sectional Study

The clinical utility of tender point (TP) examination in patients reporting chronic widespread pain (CWP) is the subject of contemporary debate. The objective of this study was to assess the relationship between mechanical hyperalgesia assessed by manual TP examination and clinical disease severity. 271 women with CWP were recruited from a clinical setting. Data collection included patient-reported symptoms, health-related quality of life variables, and observation-based measures of functional ability, muscle strength, 6-minute walk, and pressure pain thresholds measured by cuff algometry. TP examination was conducted according to ACR-guidelines. Relationships between disease variables and TP count (TPC) were analyzed with logistic regression in a continuum model, allowing the TPC to depend on the included disease variables and two regression models carried out for a TPC threshold level, varying between 1 and 17. The threshold analyses indicated a TPC threshold at 8, above which a large number of disease variables became consistently significant explanatory factors, whereas none of the disease variables reached a significance level in the continuum model. These results support the premise that the presence of mechanical hyperalgesia influences symptomatology in CWP and that the severity of clinical expression is related to a threshold of TPs, rather than being part of a continuum.

Reliability of pain measurements using computerized cuff algometry: a DoloCuff reliability and agreement study

Computerized pneumatic cuff pressure algometry (CPA) using the DoloCuff is a new method for pain assessment. Intra‐ and inter‐rater reliabilities have not yet been established. Our aim was to examine the inter‐ and intrarater reliabilities of DoloCuff measures in healthy subjects.