Intra-Rater and Inter-Rater Reliability of Pressure Pain Algometry of the Sural and Tibial Nerves in Asymptomatic Elite Youth Footballers

Ankle injuries are highly prevalent in elite youth footballers and increase the mechanosensitivity of the local neural tissue, which may predispose athletes to re-injury and prolong rehabilitation periods. Increased neural mechanosensitivity presents clinically as altered pain pressure thresholds (PPTs) which are measured with pressure algometry. The purpose of this study was to determine the intra-rater and inter-rater reliability of PPTs of the ankle neural tissue in asymptomatic elite youth football players. Three raters utilised a digital algometer to evaluate the PPTs of the Sural and Tibial nervous tissue at the ankle of elite youth male footballers. Intraclass correlation coefficients (ICCs) with 95% confidence intervals (CI) were calculated to assess intra-rater and inter-rater reliability and Bland–Altman figures were plotted to enable visual evaluation of measurement error with a significance level of p < 0.05. Thirty-four players (16–18 years old) were assessed. Excellent intra-rater (Tibial ICC 0.88 (0.76–0.94); Sural ICC 0.89 (0.79–0.95)) and good inter-rater reliability (Tibial ICC 0.66 (0.40–0.82); Sural 0.71 (0.50–0.85)) was demonstrated. Bland–Altman plots demonstrated low levels of measurement error. Pressure algometry can be utilised clinically to accurately evaluate the PPTs of the Tibial and Sural nervous tissue at the ankle in asymptomatic elite male youth footballers.

Design of an Eccentric Recumbent Ergometer to Elicit Delayed Onset Muscle Soreness

Introduction: Our objective was to design an eccentric bicycle design to elicit delayed onset muscle soreness (DOMS). Methods: To assess the bicycle designs’ ability to elicit DOMS, fourteen, recreationally active, males performed five-minutes of eccentric bicycling at 50% of their individualized power determined from a modified six-second Wingate test. Outcome measures to assess DOMS included the Likert pain scale, creatine kinase, lactate blood concentration, and pressure algometry detection evaluated at four time points (baseline (before the eccentric bicycling), immediate post, 24 hours post, and 48 hours post). Results: The Likert pain scale was different (F = 75.88, p < 0.001) at baseline (0.14 ± 0.36) and immediate post (0.21 ± 0.43), compared to 24 hours post (3.07 ± 0.83), and 48 hours post (2.93 ± 1.07). No changes were reported for creatine kinase (F = 0.7167, p = 0.475), lactate blood concentration (F = 2.313, p = 0.107), or pressure algometry detection. Conclusions: To understand mechanisms of DOMS, there is a need for a consistent, reliable method for producing DOMS. Our eccentric bicycle design and protocol offers an alternative approach to previous eccentric ergometer designs - demonstrating the potential to elicit DOMS in one, five-minute session.

The Effects of an Acute Maximal Seated Lumbar Spine Flexion Exposure on Low Back Mechanical Pain Sensitivity

Viscoelastic creep generated in the lumbar spine following sustained spine flexion may affect the relationship between tissue damage and perceived pain. Two processes supporting this altered relationship include altered neural feedback and inflammatory processes. Our purpose was to determine how low back mechanical pain sensitivity changes following seated lumbar spine flexion using pressure algometry in a repeated-measures, cross-sectional laboratory design. Thirty-eight participants underwent a 10-minute sustained seated maximal flexion exposure with a 40-minute standing recovery period. Pressure algometry assessed pressure pain thresholds and the perceived intensity and unpleasantness of fixed pressures. Accelerometers measured spine flexion angles, and electromyography measured muscular activity during flexion. The flexion exposure produced 4.4° (2.7°) of creep that persisted throughout the entire recovery period. The perception of low back stimulus unpleasantness was elevated immediately following the exposure, 20 minutes before a delayed increase in lumbar erector spinae muscle activity. Women reported the fixed pressures to be more intense than men. Sustained flexion had immediate consequences to the quality of mechanical stimulus perceived but did not alter pressure pain thresholds. Neural feedback and inflammation seemed unlikely mechanisms for this given the time and direction of pain sensitivity changes, leaving a postulated cortical influence.

Pressure Algometry for the Detection of Mechanical Nociceptive Thresholds in Horses

The clinical assessment of pain is subjective; therefore, variations exist between practitioners in their ability to identify and localize pain. Due to differing interpretations of the signs or severity of pain equine practitioners may assign varying levels of clinical significance and treatment options. There is a critical need to develop better tools to qualify and quantify pain in horses. Palpation is the most common method to detect local tenderness or sensitivity. To quantify this applied pressure, pressure algometry has been used to gradually apply pressure over specified landmarks until an avoidance response is noted, which is defined as the mechanical nociceptive threshold (MNT). Numerous studies have used pressure algometry in different applications to measure MNTs in horses. There is an acute need to establish normative values within different body regions and to develop standardized methods of testing MNTs to better guide practitioners in the diagnosis and treatment of pain. The aim of this systematic review was to summarize the evidence for the use of pressure algometry in horses. There is good evidence that pressure algometry is a repeatable, semi-objective method that can be used in a wide array of clinical and research applications to assess MNTs in horses.

Preoperative quantitative sensory testing and robot-assisted laparoscopic hysterectomy for endometrial cancer: can chronic postoperative pain be predicted?

ObjectivesChronic postoperative pain is prevalent after robot-assisted laparoscopic hysterectomy for endometrial cancer. Preoperative Quantitative Sensory Testing (QST) has been utilized to identify patients at risk of developing chronic postoperative pain after a range of surgical procedures. The aim of this prospective, observational study was to (1) determine the prevalence of chronic postoperative pain, (2) assess selected preoperative risk factors for chronic postoperative pain, and (3) evaluate if preoperative QST profiling could predict the development of chronic postoperative pain following robot-assisted laparoscopic hysterectomy for endometrial cancer.MethodsOne-hundred and sixty consecutive patients were included and handheld pressure algometry, cuff pressure algometry, temporal summation of pain, conditioned pain modulation, and heat pain thresholds were assessed prior to surgery. Patients were asked to fill out a questionnaire concerning pain in the pre- and post-operative time period six months after surgery. Chronic postoperative pain was defined as persistent, moderate to severe pain (mean visual analogue scale (VAS)≥3) on a daily basis six months after surgery.ResultsThe prevalence of chronic postoperative pain after robot-assisted laparoscopic hysterectomy for endometrial cancer was of 13.6% (95% CI 8.4–20.4%). Patients that would develop chronic postoperative pain had a lower BMI (p=0.032), a higher prevalence of preoperative pelvic pain (p<0.001), preoperative heat pain hyperalgesia (p=0.043) and a higher level of acute postoperative pain (p<0.001) when compared to patients that would not develop chronic postoperative pain. A logistic regression model demonstrated that the presence of preoperative pelvic pain was a significant, independent predictive risk factor for development of chronic postoperative pain (OR=6.62, 95% CI 2.26–19.44), whereas none of the QST parameters could predict postoperative pain.ConclusionsPreoperative QST assessment could not predict the development of chronic postoperative pain despite preoperative heat pain hyperalgesia in patients that would develop chronic postoperative pain.

Immediate effects of spinal manipulation in pain and global joint mobility in patients with chronic nonspecific low back pain

Objective: The aim of this study was to analyze the immediate effects of applying a manipulative intervention on chronic non-specific back pain and increasing global joint mobility. Method: A cross-sectional, randomized, single-blind study was carried out, consisting of 19 women aged between 18 and 55 years old, separated into two groups: Experimental Group (EG = 10) and Control Group (CG=9). The evaluation consisted of a physical examination, Rolland Morris questionnaire, fingertip-to-floor test, Visual Analogue Scale (VAS), and pressure algometry (L5) before and after the manipulative intervention. The EG was submitted to five vertebral manipulations, two in the bilateral pelvis region, one in the middle thoracic region (T5-T7) and two in the bilateral cervical region at the C3 level. The CG was submitted to two placebos manipulative techniques, being positioned in right and left lateral decubitus position for 10 seconds each, in the same position of global pelvic manipulation, but without the manipulative impulse (thrust). Results: The results were statistically significant in the EG in the reduction of sensation of pain (p<0,001) and the increase of overall joint mobility (p<0,05) when comparing pre and post intragroup moments. There were no statistically significant differences in relation to pain threshold evaluated in pressure algometry. Conclusion: It is concluded that a manipulative intervention is able to reduce the pain and to increase the global mobility immediately after its accomplishment.

Dynamic Pressure Pain Hypersensitivity as Assessed by Roller Pressure Algometry in Episodic Cluster Headache

Background: A method for assessing dynamic muscle hyperalgesia (dynamic pressure algometry) has been developed and applied in tension-type and migraine headaches. Objectives: To investigate differences in dynamic pressure pain assessment over the trigeminal area between men with cluster headache (CH) and headache-free controls, and the association between dynamic and static pressure pain sensitivity. Study Design: A case-control study. Setting: Tertiary urban hospital. Methods: Forty men with episodic CH and 40 matched controls participated. Dynamic pressure pain sensitivity was assessed with a dynamic pressure algometry set consisting of 8 rollers with different fixed levels (500, 700, 850, 1,350, 1,550, 2,200, 3,850, and 5,300 g). Each roller was moved at a speed of 0.5 cm/sec over a diagonal line covering the temporalis muscle from an anterior to posterior direction. The dynamic pressure threshold (DPT; load level of the first painful roller) and the pain intensity perceived at the DPT level (roller-evoked pain) were assessed. Static pressure pain thresholds (PPT) were also assessed with a digital pressure algometer applied statically over the mid-muscle belly of the temporalis. Patients were assessed in a remission phase, at least 3 months from the last cluster attack, and without preventive medication. Results: Side-to-side consistency between DPTs (r = 0.781, P < 0.001), roller-evoked pain on DPT (r = 0.586; P < 0.001), and PPTs (r = 0.874; P < 0.001) were found in men with CH. DPT was moderately, bilaterally, and side-to-side associated with PPTs (0.663 > r > 0.793, all P < 0.001). Men with CH had bilateral lower DPT and PPT and reported higher levels of rollerevoked pain (all P < 0.001) than headache-free controls. Limitations: Only men with episodic CH were included. Conclusions: This study supports that a dynamic pressure algometry is as valid as a static pressure algometry for assessing pressure pain sensitivity in patients with CH. Assessing both dynamic and static pain sensitivity may provide new opportunities for differentiated diagnostics. Key words: Cluster headache, dynamic pressure pain, pressure pain threshold