Left Infrapatellar Branch of the Saphenous Peripheral Nerve Stimulation Relieves Refractory Pain Following Total Knee Replacement.

Osteoarthritis, the most common joint disease of adults worldwide, is increasing in prevalence due to an increase in aging and rates of obesity in developed countries. Treatment options include physical therapy, pharmacologic management, non-pharmacologic management, and total knee replacement surgery. When conservative measures fail, total knee replacement surgery is pursued. The patient is a 61-year-old woman with a history of severe chronic osteoarthritic knee pain following total left and right knee arthroplasty in 2016 and 2019, respectively, who presents with refractory post-total knee replacement pain. Following her surgeries, the patient was in excruciating 10/10 pain on the numerical rating scale (NRS) and was unable to walk or stand. She underwent revisions which, unfortunately, did not ameliorate her pain. She was later referred to chronic pain management in which a peripheral nerve stimulator (PNS) was offered and implanted. Following her PNS trial, the patient achieved >80% pain relief in her left knee. After the permanent PNS implant, the patient noted she had 100% pain relief (0/10 on the NRS) in her left knee and was able to regain mobility. Here, we discuss a case demonstrating rapid pain relief following the minimally invasive PNS implantation for refractory pain following total knee arthroplasty. Refractory pain following total knee arthroplasty can increase morbidity and mortality as a consequence. Thus, proper management is needed to reduce these adverse outcomes. In patients who have failed conservative medical management, PNS may be an alternative, efficacious treatment option for refractory knee pain. Despite the efficacy in our case, further research is needed to define the optimal patient group that would benefit from PNS for refractory knee pain following total knee arthroplasty.