Sensory profiles in women with neuropathic pain after breast cancer surgery.

PURPOSE: We performed a detailed analysis of sensory function in patients with chronic post-surgical neuropathic pain (NP) after breast cancer treatments by quantitative sensory testing (QST) with DFNS (German Research Network on Neuropathic Pain) protocol and bed side examination (BE). The nature of sensory changes in peripheral NP may reflect distinct pathophysiological backgrounds that can guide the treatment choices. NP with sensory gain (i.e., hyperesthesia, hyperalgesia, allodynia) has been shown to respond to Na+-channel blockers (e.g., oxcarbazepine). METHODS: 104 patients with at least "probable" NP in the surgical area were included. All patients had been treated for breast cancer 4-9 years ago and the handling of the intercostobrachial nerve (ICBN) was verified by the surgeon. QST was conducted at the site of NP in the surgical or nearby area and the corresponding contralateral area. BE covered the upper body and sensory abnormalities were marked on body maps and digitalized for area calculation. The outcomes of BE and QST were compared to assess the value of QST in the sensory examination of this patient group. RESULTS: Loss of function in both small and large fibers was a prominent feature in QST in the area of post-surgical NP. QST profiles did not differ between spared and resected ICBN. In BE, hypoesthesia on multiple modalities was highly prevalent. The presence of sensory gain in BE was associated with more intense pain. CONCLUSIONS: Extensive sensory loss is characteristic for chronic post-surgical NP several years after treatment for breast cancer. These patients are unlikely to respond to Na+-channel blockers.

Recovery of mechanical detection thresholds after direct digital nerve repair versus conduit implantation.

The purpose of this study was to assess sensory and functional nerve recovery after digital nerve injury in patients with an end-to-end suture (S) or with implantation of a collagen conduit (C) to bridge a nerve gap. Fifteen S and 11 C with a follow-up of 6-36 months and 28 healthy control participants were enrolled. Methods of assessments were quantitative sensory testing, the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH), range of motion and the painDetect questionnaire. After both procedures, sensory profiles showed largely recovered function of C and Aδ fibres but severe loss of Aß-fibre function leading to increased mechanical detection thresholds. There was only minimal allodynia. Severe pain was absent. Patients with conduits reported more functional impairment, especially in work performance, which correlated with the assessed loss of Aß-fibre function. LEVEL OF EVIDENCE: III.