Hypoalgesia after exercises with painful vs. non-painful muscles in healthy subjects - a randomized cross-over study

OBJECTIVES

Exercise-induced hypoalgesia (EIH) is a decrease in the pain sensitivity after exercise. Individuals with chronic pain show less EIH after one exercise session compared with pain-free individuals possibly due to pain in exercising muscles. The primary aim of this randomized controlled cross-over study was to compare the EIH response at the exercising thigh muscle following exercises performed with painful vs. non-painful muscles. Secondary aims were to explore if a reduced EIH response was confined to the painful muscle, and whether the muscle pain intensity and the EIH responses were negatively associated.

METHODS

In two sessions, 34 pain-free participants received a painful (hypertonic saline, 5.8%) injection and a control (isotonic saline, 0.9%) injection in the right thigh muscle before performing a 3 min isometric wall squat exercise. Pressure pain thresholds (PPTs) were assessed at both thighs and the left neck/shoulder at baseline, after injections and after exercise. Pain intensities in the thighs were rated on numerical rating scales (NRS: 0-10).

RESULTS

Hypertonic saline induced moderate thigh pain at rest (NRS: 4.6 ± 2.1) compared to the control injection (NRS: 0.3 ± 0.4; p<0.001). EIH at the thighs and neck/shoulder were not different between sessions (Injected thigh: 0 kPa; 95% CI: -51 to 52; Contralateral thigh: -6 kPa; 95% CI: -42 to 30; neck/shoulder: 19 kPa; 95% CI: -6 to 44). No significant associations between pain intensity ratings immediately after the Painful injection and EIH responses at any assessment sites were found (right thigh: β=0.08, 95% CI: -12.95 to 20.64, p=0.64, left thigh: β=-0.33, 95% CI: -27.86 to 0.44, p=0.06; neck/shoulder: β=-0.18, 95% CI: -15.11 to 4.96, p=0.31).

CONCLUSIONS

Pain in the area of an exercising muscle did not reduce local or systemic EIH responses.

TRIAL REGISTRATION NUMBER

NCT04354948.

Testosterone replacement therapy of opioid-induced male hypogonadism improved body composition but not pain perception: a double-blind, randomized, and placebo-controlled trial

BACKGROUND

Hypogonadism is prevalent during opioid treatment, but the effect of testosterone replacement treatment (TRT) on body composition, pain perception, and adrenal function is unclear.

PURPOSE

To measure changes in body composition, pain perception, quality of life, and adrenal function after TRT or placebo in opioid-treated men with chronic non-malignant pain.

METHODS

Double-blind, placebo-controlled study in 41 men (>18 years) with total testosterone <12 nmol/L were randomized to 24 weeks TRT (Testosterone undecanoate injection three times/6 months, n = 20) or placebo (placebo-injections, n = 21).

OUTCOMES

Body composition (lean body mass and fat mass assessed by DXA), clinical pain intensity (numerical rating scale), and experimental pain perception (quantitative sensory assessment), quality of life (SF36), and adrenocorticotrophic hormone (ACTH) test. Data were presented as median (quartiles). Mann-Whitney tests were performed on delta values (24-0 weeks) between TRT and placebo.

RESULTS

The median age was 55 years (46; 59) and total testosterone before intervention was 6.8 (5.0; 9.3) nmol/L. TRT was associated with change of testosterone levels: 12.3 (7.0; 19.9) nmol/L (P < 0.001 vs placebo), increased lean body mass: 3.6 (2.3; 5.0) kg vs 0.1 kg (-2.1; 1.5) during TRT vs placebo and decreased total fat mass: -1.2 (-3.1; 0.7) kg vs 1.2 kg (-0.9; 2.5) kg, both P < 0.003. Changed pain perception, SF36, and ACTH-stimulated cortisol levels were non-significantly changed during TRT compared with placebo.

CONCLUSIONS

Six months of TRT improved body composition in men with opioid-induced hypogonadism without significant changes in outcomes of pain perception, quality of life, or adrenal function.

Chronic pain patients with possible co-morbid post-traumatic stress disorder admitted to multidisciplinary pain rehabilitation-a 1-year cohort study

BACKGROUND

Although post-traumatic stress disorder (PTSD) is a common co-morbidity in chronic pain, little is known about the association between PTSD and pain in the context of chronic pain rehabilitation.

OBJECTIVE

The aim of the present study was two-fold: (1) to investigate the association of a possible PTSD diagnosis with symptoms of pain, physical and mental functioning, as well as the use of opioids, and (2) to compare the outcome of multidisciplinary chronic pain rehabilitation for patients with a possible PTSD diagnosis at admission with patients without PTSD at admission.

METHOD

A consecutively referred cohort of 194 patients completed a baseline questionnaire at admission covering post-traumatic stress, pain symptoms, physical and mental functioning, as well as self-reported sleep quality and cognitive difficulties. Medication use was calculated from their medical records. A total of 95 were admitted to further multidisciplinary treatment and included in the outcome study.

RESULTS

A high prevalence of possible PTSD was found (26.3%). Patients with possible co-morbid PTSD experienced significantly poorer general and mental health, poorer sleep quality, and more cognitive problems as well as inferior social functioning compared to patients without PTSD. Possible co-morbid PTSD did not result in higher use of opioids or sedatives. Surprisingly, possible co-morbid PTSD at admission was not associated with lower levels of symptom reduction from pre- to post-treatment.

CONCLUSIONS

Possible co-morbid PTSD in chronic pain is a major problem associated with significantly poorer functioning on several domains. Nevertheless, our results indicate that pain-related symptoms could be treated with success despite possible co-morbid PTSD. However, since PTSD was only measured at admission it is not known whether rehabilitation actually reduced PTSD.

[Stomach rupture after nasal oxygen therapy]

A 69-year-old male developed a spontaneous rupture of the normal stomach during oxygen administration via a nasopharyngeal catheter. The clinical picture and treatment is discussed.

Treatment of Bartholin's abscess. Marsupialization versus incision, curettage and suture under antibiotic cover. A randomized study with 6 months' follow-up

Conventional marsupialization was compared with incision plus curettage and primary suture of the abscess cavity under antibiotic (Clindamycin) cover in a prospective, randomized study of 32 patients with Bartholin's abscess. The median time to healing was 5 days less after suture than after marsupialization alone. The difference was statistically significant. 29 patients were followed up for 6 months. Recurrence of abscesses tended not to be more frequent after suture, making suture an attractive, safe and convenient alternative treatment for Bartholin's abscess.