Devices

A research-grade self-sizing spiral cuff electrode implementation used in chronic human peripheral nerve stimulation studies, including sensory stimulation in upper-limb amputees.

Device — Peripheral nerve

CWRU self-sizing spiral nerve cuff (upper-limb sensory stimulation research deployments)

Official site →

PNI · spiral cuff · self-sizing · CWRU · sensory feedback · amputation · stimulation · peripheral nerve · cuff

CWRU self-sizing spiral nerve cuff (upper-limb sensory stimulation research deployments)

One-line verdict: A research-grade, non-penetrating self-sizing spiral cuff implementation that achieves durable peripheral nerve stimulation (and measurable selectivity) with relatively low surgical risk, at the cost of limited channel density.

Quick tags: Stimulation · Channels: multi-contact (configuration varies) · Species: Human

Overview

What it is: A self-curling polymer spiral cuff electrode (rooted in the Naples/Mortimer spiral cuff design family) that wraps around a peripheral nerve and provides extraneural stimulation through multiple contacts. This entry focuses on well-documented human research deployments associated with CWRU/Cleveland VA programs, including chronic multi-contact cuff stimulation for sensory feedback in upper-limb amputees.

Why it matters: It is one of the best-documented long-duration human extraneural cuff implementations, with multi-year stability data (contact functionality and threshold stability) and functional neuroprosthesis outcomes.

Most comparable devices: split-cylinder cuffs; FINE/C-FINE (more selectivity); intraneural LIFE/USEA (more selectivity, more invasiveness).

Spec Card Grid

Identity

  • Device name: CWRU self-sizing spiral nerve cuff electrode (research implementation)
  • Canonical ID: BTSD-PNI-0003
  • Org / manufacturer: research implementations (CWRU / Cleveland VA programs; not a single commercial SKU)
  • First demonstrated (year): 1988 (spiral cuff family)
  • First implanted (year): chronic human implants reported in mid-2000s onward (study-dependent)
  • Species: human
  • Regulatory / trial status: research implants (IRB/IDE context varies)
  • Primary use: stimulation (motor and sensory neuroprostheses)
  • Primary target: peripheral nerves; includes upper-limb nerves (median/ulnar/radial) in amputee sensory studies

Geometry & Architecture

  • Interface type: peripheral nerve cuff (spiral, self-sizing)
  • Penetrating?: no
  • Form factor: spiral cuff wraps around nerve (self-curling sheath)
  • Array layout: circumferentially spaced contacts; contact count varies by study/nerve
  • Insertion method: surgical exposure; place cuff around nerve; route leads to implanted or percutaneous connectors depending on study system
  • Anchoring method: mechanical conformity + lead strain relief

Electrode & Channel Physics

  • Channel count: multi-contact (varies)
  • Electrode material: not pinned here (varies)
  • Recording modality: typically stimulation-focused; cuffs can record CAP/LFP in some setups
  • Stimulation capability: yes

Tissue Interface & Bioresponse

  • Target tissue: extraneural cuff on peripheral nerve epineurium
  • Encapsulation: fibrotic encapsulation expected; long-term studies report stable function despite encapsulation changes
  • Typical failure mode: lead strain/pull-off or connector issues; infection risk higher if percutaneous connectors used

System Architecture

  • Onboard electronics: none in cuff
  • Data path: lead to implanted stimulator or external stim (study-dependent)

Performance Envelope

  • Stability over time: multi-year stability of contact functionality and thresholds reported in human cohorts
  • Longevity: cohort-dependent; multi-year mean and up-to ~10-year-class follow-up reported for stimulating spiral cuffs

Clinical / Preclinical Evidence

  • Evidence base: chronic human studies of spiral cuff stimulation; upper-limb amputee sensory stimulation studies using multi-contact cuffs
  • Key limitations of evidence: heterogeneous nerves, tasks, and system architectures

Engineering Verdict

Strengths:

  • long-term human evidence for durability and stable stimulation performance
  • lower invasiveness than intraneural arrays

Limitations / failure modes:

  • lower channel density/selectivity than higher-density cuff variants (e.g., FINE) or intraneural interfaces
  • lead routing and connector choice drives a lot of real-world reliability

References