10 kHz spinal cord stimulation for chronic upper limb and neck pain: Australian experience

Intractable upper limb and neck pain has traditionally been a challenging pain condition to treat, with conventional spinal cord stimulation (SCS) often inducing positional variation in paraesthesia and/or inadequate coverage of axial neck pain. The purpose of this Australian multi-centre prospective, clinical trial was to assess the safety and effectiveness of paraesthesia-independent 10 kHz SCS for the treatment of upper limb and neck pain. Subjects with chronic, intractable neck and/or upper limb pain of ≥ 5 cm (on a 0–10-cm visual analogue scale) were enrolled (ACTRN12614000153617) following human research ethics committee approval. Subjects were implanted with two epidural leads spanning C2–C6 vertebral bodies. Subjects with successful trial stimulation were implanted with a Senza® system (Nevro Corp., Redwood City, CA, USA) and included in the safety and effectiveness evaluation at 3 months post-implant (primary endpoint assessment, PEA) and followed to 12 months. Overall, 31/38 (82.6%) subjects reported a successful 10 kHz SCS trial and proceeded to a permanent implant. Twenty-three of 30 subjects (76.7%) met the PEA. Subjects reported a reduction in neck pain and upper limb pain from baseline at the PEA (8.1 ± 0.2 cm vs. 2.9 ± 0.5 cm, 7.3 ± 0.3 cm vs. 2.5 ± 0.5 cm, respectively, p ≤ 0.0001). Disability, as measured by pain disability index score, decreased from 42.6 ± 2.6 at baseline to 22.7 ± 3.2 at PEA. Results were maintained 12 months post-implant. No neurological deficits, nor reports of paraesthesia, were observed. Stable, long-term results demonstrated that 10 kHz SCS is a promising therapy option for intractable chronic upper limb and neck pain.