Quantitative Sensory Testing (QST) - Does assessing ... - TI Pharma

5. QST in patients with tendinopathy
(QST) it is possible to assess perceptual functioning of somatosensory modalities
that correspond with distribution areas to peripheral nerve fibres and CNS pathways
(Hansson et al 2007; Rolke et al 2006a). QST examines large fibre function (Aβ), and
nociceptive small fibre (Aδ, C) functions, all of which may be involved in peripheral
and central pain syndromes (Rolke et al 2006a). As QST is a form of psychophysical
testing, alertness and cooperation of the patient is required for obtaining reliable test
results. The cause of abnormal results may lie anywhere along the sensory pathway;
from the peripheral receptor to the highest cortical regions in the brain (Chong & Cros
2004; Hansson et al 2007; Shy et al 2003).
Currently, little is known whether, or to which degree, somatosensory changes
may contribute to the pain in tendinopathies and other sports injuries. Jensen et al.
investigated the presence of neuropathic pain mechanisms in 91 patients with chronic
patellofemoral pain syndrome (Jensen et al 2008). They used somatosensory testing’s
and found significant hypesthesia on the affected side as opposed to the patients’ own
unaffected, contralateral side. In a clinical pilot study in patients with general chronic
sports injuries we found signs of sensitisation in 27 % of the athletes and additional 13
% showed signs of hypoalgesia (van Wilgen & Keizer 2011).
The primary goal of this study is to investigate whether somatosensory changes
represent a plausible explanation for pain in patient with chronic patellar tendinopathies
and secondly to investigate if psychological co-morbidities may contribute to pain in
tendinopathy.
2. Methods
2.1. Participants
In this patient controlled study we included only male athletes with PT and male
volleyball, basketball and soccer-players without PT in a control group. We included
only male participants as gender differences have been reported for several QST
parameters (Rolke et al 2006a). Patients with PT, diagnosed by an experienced sports
medicine physician or sports physical therapists were asked to participate in the study.
The diagnostic criteria for PT included a characteristic history of knee pain in the
proximal patellar tendon related to exercise and tenderness upon palpation of the
patellar tendon. Patients with PT were included if their pain had been present for at
least 6 months and if they scored lower than 80 points on the Victorian Institute of
Sports Assessment – Patellar Questionnaire (VISA-P). The VISA-P is a validated, selfadministered
questionnaire that is frequently used to evaluate the severity of symptoms,
knee function and sports participation of athletes with PT (Visentini et al 1998). The
psychometric properties of this questionnaire and the Dutch version in injured athletes