Persistent Pain One Year after Total Knee Arthroplasty is Associated with Abnormal QST
This study investigates the difference in quantitative sensory testing (QST) results and self-reported neuropathic pain in patients after Total Knee Arthroplasty (TKA) surgery with and without persistent pain. The results shows that patients with persistent post-operative pain demonstrate widespread mechanical, cold and heat hyperalgesia and also higher level of neuropathic-like pain.
Total Knee Arthroplasty brings on pain relief and improves the knee functionality for most patient who have undergone TKA. However, up to 15% of patients suffer from persistent post-operative pain after the surgery.
The aim of this study was to determine if such persistent pain is associated with neuropathic-like pain and QST changes. To answer the above questions, 53 patients after TKA surgery were recruited, some with moderate to severe pain and some without pain.
Patients completed self-report questionnaires and underwent QST, including pressure pain threshold, cold and heat pain threshold and cold and warm detection threshold tests on the operated knee and on the elbow.
The results demonstrated that there was an association between moderate to severe pain reported after the surgery and widespread mechanical and cold and heat hyperalgesia. Patients with persistent pain also demonstrated higher levels of neuropathic-type pain and less functional improvement after the surgery.
The results suggest that some patients after TKA surgery continue to suffer from knee pain and dysfunction and raises a need for larger study assessing these patient pre- and post-operatively.
To read the full-text article: Wright, A., Moss, P., Sloan, K., Beaver, R. J., Pedersen, J. B., Vehof, G., ... & Cheong, P. (2015). Abnormal quantitative sensory testing is associated with persistent pain one year after TKA.Clinical Orthopaedics and Related Research®,473(1), 246-254.