TY - JOUR
T1 - Pressure-induced referred pain areas are more expansive in individuals with a recovered fracture
AU - Doménech-García, Víctor
AU - Skuli Palsson, Thorvaldur
AU - Boudreau, Shellie Ann
AU - Herrero, Pablo
AU - Graven-Nielsen, Thomas
N1 - DNRF121
PY - 2018/10
Y1 - 2018/10
N2 - Musculoskeletal trauma and pain can sensitize central pain mechanisms but whether these normalize upon recovery is unknown. This study compared the extent of pain referral in individuals recovered from a musculoskeletal trauma and healthy controls. Twenty pain-free participants recovered from a shoulder fracture and 20 age/gender matched controls participated in two experimental sessions (Day-0, Day-1) separated by 24 hours. On both days, pressure pain thresholds (PPTs) were measured bilaterally at infraspinatus, supraspinatus, trapezius, and gastrocnemius muscles. Referred pain towards the shoulder region was induced by a 60-s pressure stimulation (PPT+20%) at the infraspinatus muscle and recorded on an electronic body chart. Following Day-0 assessments, delayed onset muscle soreness (DOMS) was induced to challenge the pain systems by exercising the external rotators of the recovered/dominant shoulder. The size of pressure-induced pain referral on Day-0 did not differ between groups although there was a tendency for a smaller referred pain area in recovered group. PPTs at the infraspinatus muscle on the DOMS side was reduced on Day-1 in both groups (P=0.03). An expansion of pressure-induced pain referral was found in both groups following the DOMS protocol on Day-1 (P=0.05) with a relatively larger expansion (P=0.05) and higher frequency of pain in the shoulder (P=0.04) in the recovered pain group. Following complete recovery and absence of pain symptoms after a fracture, central pain mechanisms seem to normalize in the region of the trauma following recovery but when sensitized a heightened response can emerge. Such mechanisms could be important for recurrence of pain conditions.
AB - Musculoskeletal trauma and pain can sensitize central pain mechanisms but whether these normalize upon recovery is unknown. This study compared the extent of pain referral in individuals recovered from a musculoskeletal trauma and healthy controls. Twenty pain-free participants recovered from a shoulder fracture and 20 age/gender matched controls participated in two experimental sessions (Day-0, Day-1) separated by 24 hours. On both days, pressure pain thresholds (PPTs) were measured bilaterally at infraspinatus, supraspinatus, trapezius, and gastrocnemius muscles. Referred pain towards the shoulder region was induced by a 60-s pressure stimulation (PPT+20%) at the infraspinatus muscle and recorded on an electronic body chart. Following Day-0 assessments, delayed onset muscle soreness (DOMS) was induced to challenge the pain systems by exercising the external rotators of the recovered/dominant shoulder. The size of pressure-induced pain referral on Day-0 did not differ between groups although there was a tendency for a smaller referred pain area in recovered group. PPTs at the infraspinatus muscle on the DOMS side was reduced on Day-1 in both groups (P=0.03). An expansion of pressure-induced pain referral was found in both groups following the DOMS protocol on Day-1 (P=0.05) with a relatively larger expansion (P=0.05) and higher frequency of pain in the shoulder (P=0.04) in the recovered pain group. Following complete recovery and absence of pain symptoms after a fracture, central pain mechanisms seem to normalize in the region of the trauma following recovery but when sensitized a heightened response can emerge. Such mechanisms could be important for recurrence of pain conditions.
U2 - 10.1097/j.pain.0000000000001234
DO - 10.1097/j.pain.0000000000001234
M3 - Journal article
C2 - 29608510
SN - 0304-3959
VL - 159
SP - 1972
EP - 1979
JO - Pain
JF - Pain
IS - 10
ER -