Evaluation of low back pain: comparative study between psychophysical methods

Electrical impedance of the torso is associated with the pressure pain threshold on myofascial trigger points in patients with chronic neck pain: A cross-sectional study

BACKGROUND

Myofascial trigger points are dysfunctional structures present in skeletal muscles and are related to sensory, motor, and autonomic changes. Despite scientific advances in recent decades in the measurement of musculoskeletal pain, evaluation of this clinical phenomenon is supported with instruments that, although valid and reliable, have a considerable degree of subjectivity.

OBJECTIVE

To correlate electrical impedance of the upper limbs and torso with pain intensity, functional capacity, catastrophizing, pressure pain threshold, and skin temperature on myofascial trigger points in the upper trapezius muscle of patients with neck pain.

METHODS

A single-blind cross-sectional study. Twenty-eight volunteers of both genders were included in the study, were aged 18-45 years, and had chronic neck pain and myofascial trigger points in the upper trapezius. The volunteers were assessed using the Numeric Rating Scale, the Neck Disability Index, the Pain-Related Self-Statement Scale, algometry, infrared thermography, and electrical bioimpedance.

RESULTS

The following significant results were observed: a negative association between the pressure pain threshold on myofascial trigger point in the right upper trapezius and electrical impedance of the torso at 5 kHz (rs=-0.392, p= 0.032), 50 kHz (rs=-0.406, p= 0.026), 250 kHz (rs=-0.388, p= 0.034), and to the frequency 500 kHz (rs=-0.444, p= 0.014).

CONCLUSION

Electrical impedance of the torso is associated with the pressure pain threshold of myofascial trigger points on the upper trapezius of individuals with neck pain. Thus, individuals with a lower pressure pain threshold have higher electrical impedance values of the torso and vice versa.

Reliability of skin impedance in subjects with chronic neck pain

BACKGROUND

Skin impedance is a biological signal that has been employed in the measurement of pain. However, there are few scientific data on skin impedance, with a great variety of assessment methods and controversial results.

OBJECTIVE

To examine the intra- and inter-rater reliability of skin impedance measurement in individuals with chronic neck pain.

METHODS

This is a blind cross-sectional study. Thirty individuals of both genders, aged between 18 and 45 years and with chronic neck pain were included in the study. Two examiners assessed skin impedance of the upper and lower limbs and torso at two intervals separated by one week. For statistical analysis, we used the intraclass correlation coefficient (ICC2,3) to determine the intra- and inter-rater reliability of skin impedance, with its respective confidence interval of 95%, standard error of measurement (SEM) and minimum detectable change (MDC).

RESULTS

The intra-rater reliability was considered substantial to excellent, with ICC values ranging between 0.843 and 0.978, SEM between 0.58 and 15.26 Ω, and MDC between 1.61 and 42.31 Ω. The inter-rater reliability was moderate to excellent, with ICC values ranging between 0.761 and 0.997, SEM ranging between 0.22 and 16.72 Ω, and MDC ranging between 0.63 and 46.35 Ω.

CONCLUSION

The measurement of skin impedance of the upper and lower limbs and torso in individuals with chronic neck pain has acceptable reliability values when considered at different times and by different examiners.

Indução da dor pelo quimioterápico docetaxel em mulheres com câncer de mama

Resumo Objetivo Descrever a frequência, características, localização, intensidade da dor em pacientes com câncer de mama em uso do quimioterápico Docetaxel. Métodos Estudo longitudinal realizado com 17 mulheres com câncer de mama em tratamento com Docetaxel. As pacientes foram avaliadas durante três ciclos da quimioterapia quanto à dor, utilizando-se os instrumentos Questionário McGill de Dor (Br-MPQ) e Brief Pain Inventory (BPI). Utilizou-se a correlação de Spearman e o teste de Mann-Whitney. Resultados Houve aumento na média da dor em todas as variáveis do BPI. Quando comparados os valores do Pain Rating Index (PRI) total foram verificados respectivamente 0,20; 0,33 e 0,24 na primeira, segunda e terceira avaliações, sendo encontrada correlação entre a intensidade da dor e a interferência em todas as atividades do cotidiano no BPI na segunda avaliação. Conclusão Houve aumento na ocorrência da dor, comprometendo as atividades diárias de vida das mulheres participantes.

Characterization of chronic pain in breast cancer survivors using the McGill Pain Questionnaire

The aim of the present study was to characterize pain in breast cancer survivors using the McGill Pain Questionnaire (MPQ). A descriptive, cross-sectional study was conducted with 30 women aged 30-80 years who had been submitted to treatment for breast cancer (surgery and complementary treatment) at least 12 months earlier with reports of pain related to the therapeutic procedures. Pain was characterized using the full-length version of the MPQ, which is made up of 78 descriptors divided into four categories: sensory (ten items), affective (five items), evaluative (one item) and miscellaneous (four items). Two indices were also used to measure pain through the use of the descriptors: the number of words chosen (NWC) and the pain rating index (PRI). The most frequent descriptive terms were "agonizing" (n = 16; 53.3%), "tugging" (n = 15; 50%), "sore" (n = 14; 46.7%), "wretched" (n = 14; 46.7%), "troublesome" (n = 13; 43.3%) and "spreading" (n = 11; 36.7%). The sensory category had the highest PRI value based on the descriptors chosen (mean: 0.41). Women with chronic pain following treatment for breast cancer employed the "agonizing", "tugging" and "sore" descriptors with greatest frequency and rated pain in the sensory category as having the greatest impact.

Assessing the impact of pain on the life of breast cancer survivors using the Brief Pain Inventory

[Purpose] This study attempted to assess the impact of pain on the life of breast cancer survivors using the Brief Pain Inventory (BPI). [Subjects and Methods] A cross-sectional study was conducted. Participants comprised 30 women, aged 30-80 years, who had received treatment for breast cancer (surgery and complementary treatment) at least 12 months prior to the study and had reported chronic pain related to the treatment procedures. [Results] The highest scores were found for "mood" (median: 5.00 points; first quartile: 1.00 points; third quartile: 7.25 points), "normal work" (median: 5.00 points; first quartile: 0.00 points; third quartile: 8.00 points), and "sleep" (median: 4.50 points, first quartile: 0.00 points, third quartile: 8.00 points). [Conclusion] Pain exerts a negative impact primarily on mood, normal work, and sleep among breast cancer survivors.

Evaluation of the perception of chronic ischemic pain in humans with peripheral arterial disease

The perception of pain is multidimensional, subjective, and unique to each individual and can be influenced by several dimensions of pain. The objective of this study was to evaluate the perception of chronic ischemic pain using the descriptors of pain and to rate the main descriptors of chronic pain to people with peripheral arterial disease (PAD). The study was conducted in two hospitals in Brazil and consisted of two phases. In phase I, 100 participants with a diagnosis of PAD and chronic pain evaluated 50 descriptors of pain using the Multidimensional Pain Evaluation Scale by the psychophysical method of category estimation using a numerical scale with 11 points. In phase II, 30 participants judged the 10 first descriptors selected in phase I by the psychophysical method of magnitude estimation. The average intensity of chronic ischemic pain was 5.59 ± 3.16. The descriptors of chronic pain with higher scores obtained by the method of category estimation were unpleasant, followed by disturbing, strong, concern, tiring, boring, terrible, painful, sickening, and uncomfortable. By the method of magnitude estimation, the descriptors of pain showing sensitive, affective, and cognitive dimensions were identified by the descriptors terrible, follow by painful, uncomfortable, concern, tiring, sickening, strong, disturbing, boring, and unpleasant. This study showed that the chronic ischemic pain by PAD is associated with multidimensional components of pain.