Ultrasound-Guided Dry Needling As a Treatment For Postmastectomy Pain Syndrome - A Case Series of Twenty Patients.

Context: Existing interventions for postmastectomy pain syndrome (PMPS) address the neural component while overlooking a possible myofascial component.

Aim: The aim of the study is to investigate the myofascial contribution to PMPS, by examining the effectiveness of myofascial trigger point release by ultrasound-guided dry needling (USGDN).

Patients and Methods: This retrospective review assessed the efficacy of USGDN in addressing myofascial pain in twenty consecutive patients with treatment-refractory PMPS. Patients in Group 1 ( n = 16) received USGDN after neural interventions (NIs) such as neuraxial blocks, intrathecal pump implant, or pulsed radiofrequency, while those in Group 2 ( n = 4) received USGDN alone. Outcome measures were changes in Numerical Rating Scale (NRS), PainDETECT (PD), Disabilities of Arm, Shoulder, and Hand (DASH), Patient Health Questionnaire-9 (PHQ-9) scores, and opioid use.

Results: In Group 1, the mean (standard deviation) NRS and PD scores (9.6 [0.9] and 28.3 [4.3], respectively, at baseline) reduced to 5.2 (1.1) and 16.1 (3.7) at 1-week post-NI. The post-NI DASH reduction was below the cutoff for clinical relevance (80.9 [10.5] at baseline vs. 71.1 [10.5] post-NI). The opioid dose remained unchanged. Following USGDN, NRS, PD, and DASH scores further reduced to 2.3 (0.8), 6.6 (1.2), and 34.6 (14.4), respectively. Patients receiving USGDN alone also showed reduction in NRS, PD, and DASH (7.8 [1.7], 20.0 [8.0], and 61.0 [14.4] at baseline vs. 1.3 [0.5], 6.0 [1.6], and 22.5 [10.4] post-USGDN, respectively). In all patients, opioid use and PHQ-9 scores reduced only post-USGDN.

Conclusions: USGDN reduced pain, disability, and opioid use, whereas NI reduced only pain. This suggests a myofascial contribution to pain and disability in PMPS.