Patients with greater trochanteric pain syndrome (GTPS) may have altered conditioned pain modulation, as well as a high number of pain locations associated with negative conditioned pain modulation, according to an observational study published in Pain Medicine.
A total of 49 patients with trochanteritis who were referred to a primary healthcare physical therapy unit were enrolled in the study. At the time of presentation, patients had unilateral lateral hip pain and tenderness on palpation at the greater trochanter. A questionnaire was administered to each patient to collect sociodemographic data, including sex, age, height, weight, pain side, marital status, occupational status, and actual pain intensity and location. Widespread pain was also evaluated in patients who reported several pain locations. The self-reported Spanish version of the Graded Chronic Pain Scale and the visual analog scale were used to assess pain severity and pain intensity, respectively.
In this cohort, 35% of participants had a negative moderate correlation between conditioned pain modulation and right view percentage of pain location (P <.05). There was also a significant low negative correlation between the percentage of pain location and the temporal summation at the major trochanter (P <.05) and a moderate positive correlation between the Graded Chronic Pain Scale score and the pressure pain detection threshold at the trochanter (P <.01). A large correlation was also established between the Graded Chronic Pain Scale score and the posterosuperior iliac spine and epicondyle (P <.01 for both).
Limitations of the study include the lack of pain-free healthy control participants, the small cohort, and the cross-sectional study design.
“[P]hysicians could apply these outcome measurements to assess patients with GTPS who attend primary care and determine the presence of central sensitization in order to include these patients in adequate multimodal treatment approaches,” the researchers concluded.
Reference
Ferrer-Peña R, Muñoz-García D, Calvo-Lobo C, Fernández-Carnero J. Pain expansion and severity reflect central sensitization in primary care patients with greater trochanteric pain syndrome [published online October 11, 2018]. Pain Med. doi:10.1093/pm/pny199