Activating the Somatosensory System Improves Gait Metrics Linked to Pain in Patients with Total Knee Replacements

Even moderate knee pain following total knee replacement (TKR) can cause quadriceps inhibition during walking that presents a barrier to restoring quadriceps muscle function. Further, reduced muscle function during walking is likely a factor in the incidence of decreased TKR patient satisfaction [1]. Thus, TKR patients could benefit from new therapeutic methods to mitigate knee pain and enhance quadriceps function during walking. One potential therapeutic method comes from a device that applies an intermittent vibrational stimulus, designed to activate the somatosensory system during walking in a manner that gates pain [2]. While wearing the device, patients with knee pain improved their gait in a manner that reflected increased quadriceps function with increased peak knee flexion moment (KFM) and increased midstance knee flexion angle (MSKFA) [2]. Evidence that the KFM has been related to pain [3] and people with TKRs present with lower MSKFA [4] provided motivation to test this device in individuals with TKRs. This study tested the following hypotheses: (1) At baseline (no device), TKR patients’ patient reported outcomes (PROs) are correlated with MSKFA and peak KFM, and (2) Patients wearing the device with the vibrational stimulus will have increases in MSKFA and KFM that are correlated to PROs.