Perioperative percutaneous peripheral nerve stimulation utilizing preoperative lead placement for the treatment of postoperative pain
Introduction. Severe, long-lasting pain is a major treatment challenge following total knee arthroplasty (TKA): the median time to opioid cessation is often several weeks/months, and a majority of patients have difficulty with activities of daily living ≥6-12 months. Percutaneous peripheral nerve stimulation (PNS) may decrease post-TKA pain,1 but peer-reviewed articles describe its use only 6-98 days following surgery for less than 1 hour.2,3 The objective of the present case series was to investigate the use of percutaneous PNS to control pain, decrease opioid use, and accelerate functional recovery following TKA from the immediate postoperative period through up to 6 weeks.
Case Series. The investigation was approved by the FDA under an investigational device exemption, and IRB approval was obtained. All subjects provided written, informed consent. For patients undergoing a primary, unilateral TKA, both femoral and sciatic open-coil percutaneous leads (SPR Therapeutics, Cleveland, OH) were placed preoperatively using ultrasound guidance. The leads were connected to external stimulators which generated comfortable sensations in the knee from placement (1-14 days prior to surgery) until just prior to surgery, at which time the leads were disconnected from the stimulators and secured beneath sterile bandages. An ultrasound-guided, single-injection adductor canal block was administered with ropivacaine 0.5% and epinephrine (20 mL). Surgical anesthesia was provided with a spinal or general anesthetic. The following morning, stimulators were reconnected to the leads and activated. After hospital discharge, subjects continued using stimulation for up to 6 weeks, after which the leads were removed by an investigator. Walking ability (Six Minute Walk Test; 6MWT) and function (Western Ontario and McMaster Universities Osteoarthritis Index; WOMAC) were assessed preoperatively, and at 2 weeks and 6 weeks postoperatively.
In 6 of 7 subjects (86%), the average of daily pain scores across the first 2 weeks was well controlled and mild (<4 on the 0-10 Numeric Rating Scale for pain; Table). Of 5 subjects with data on opioid usage, 3 (60%) had ceased opioid use within the first 2 weeks (median time to opioid cessation=8 days). Gross sensory/motor function was maintained during stimulation, enabling stimulation during physical therapy and activities of daily living. Two weeks following surgery, 6 of 7 subjects had returned approximately to preoperative levels on the 6MWT (≥95% of preoperative distance), and WOMAC scores improved by an average of 46% compared to before surgery. No falls, motor block, or lead infections were reported.4 One lead (7%) was inadvertently dislodged during stimulation, and 3 of 14 leads (21%) were fractured during intentional extraction (the fragments were left in situ). Of note, retained fragments have not produced complications and MRI scanning may still be subsequently performed when left in situ (n=275).1,5
Conclusions. This case series suggests that a novel option for postoperative pain control, perioperative percutaneous PNS, may provide analgesia without the undesirable effects of traditional analgesics such as opioid-related respiratory depression, nausea, and sedation; or local anesthetic-induced quadriceps weakness and proprioception deficits of central/peripheral nerve blocks. Ongoing and future studies will be conducted to continue to evaluate the safety and effectiveness of percutaneous PNS.
1. Ilfeld BM, Grant SA: Ultrasound-guided percutaneous peripheral nerve stimulation for postoperative analgesia: Could neurostimulation replace continuous peripheral nerve blocks? Reg Anesth Pain Med 2016; 41: 720-722
2. Ilfeld BM, Grant SA, Gilmore CA, Chae J, Wilson RD, Wongsarnpigoon A, Boggs JW: Neurostimulation for postsurgical analgesia: A novel system enabling ultrasound-guided percutaneous peripheral nerve stimulation. Pain Pract 2016: In Press
3. Ilfeld BM, Gilmore CA, Grant SA, Bolognesi MP, Del Gaizo DJ, Wongsarnpigoon A, Boggs JW: Ultrasound-guided percutaneous peripheral nerve stimulation for analgesia following total knee arthroplasty: A prospective feasibility study. J Orthop Surg Res: In Press
4. Ilfeld BM, Gabriel RA, Saulino MF, Chae J, Peckham PH, Grant SA, Gilmore CA, Donohue MC, deBock MG, Wongsarnpigoon A, Boggs JW: Infection rates of electrical leads used for percutaneous neurostimulation of the peripheral nervous system. Pain Pract 2016: ePub
5. Shellock F, Chae J, Ilfeld BM, Strother R: In vitro MRI evaluation of the open-coil lead used for percutaneous peripheral nerve stimulation [abstract]. North American Neuromodulation Society Annual Meeting: In Press
SPR Therapeutics, LLC (Cleveland, Ohio) provided funding and the peripheral nerve electrical leads and stimulators used in this investigation.
Brian Ilfeld: Dr. Ilfeld’s institution has received funding for his research from SPR Therapeutics (including this investigation), Baxter Healthcare, Smiths Medical, Summit Medical, Teleflex Medical, Myoscience, Pacira Pharmaceuticals, and Heron Pharmaceuticals. In addition, Dr. Ilfeld previously acted in the role of a consultant to Pacira Pharmaceuticals.
Stuart Grant: Dr. Grant’s institution has received funding for his research from SPR Therapeutics (including this investigation), Cara Therapeutics, and Durrect. Dr. Grant also acts as a consultant to BBraun Medical.
Amorn Wongsarnpigoon: Dr. Wongsarnpigoon is an employee of SPR Therapeutics.
Joseph W. Boggs: Dr. Boggs is an employee of SPR Therapeutics and owns equity in the company.
Other investigators: Their institution (UCSD) has received funding for their research from SPR Therapeutics (including this investigation), Baxter Healthcare, Smiths Medical, Summit Medical, Teleflex Medical, Myoscience, Pacira Pharmaceuticals, and Heron Pharmaceuticals.