Shifting pain phenotypes with physical therapy treatment: an exploration study
Adriaan Louw1,2,3, Merrill R Landers3, Kevin Farrell1,2
1Pain Science Division, Evidence in Motion, Story City, IA, USA.
Background:
Pain phenotyping classifies a patient's pain as nociceptive, peripheral neuropathic, or nociplastic and should drive examination and treatment options. While it is theoretically possible for patients to transition between pain phenotypes during treatment, empirical clinical evidence for such changes remains unknown.
Objective:
To explore if pain phenotype clinical presentations shift during the course of physical therapy treatment.
Methods:
Patients attending outpatient physical therapy for musculoskeletal pain had their predominant pain phenotype evaluated by the attending clinician at the initial consultation. Patients received usual care per the attending clinician's discretion, and pain phenotype assessment was repeated at visits 3 and 6 by the same clinician.
Results:
Ninety-two patients were assessed and treated. There was a statistically significant difference among the means, χ2(2) = 10.133, p = 0.006. Post hoc comparisons revealed no significant difference between the evaluation phenotype and the visit 3 phenotype (p = 0.055). However, there were statistically significant differences between the visit 3 phenotype and the visit 6 phenotype (p = 0.023) and between the evaluation phenotype and the visit 6 phenotype (p = 0.018). The data suggest that participants' phenotypes changed from more complex (nociplastic) to less complex (nociceptive) over the duration of treatment.
Conclusion:
Pain phenotypes may shift during physical therapy. Additional research is needed to determine what additional clinical and non-clinical factors are associated with shifts in pain phenotypes during physical therapy.
