Abstract / Summary
Abstract Background Pain and gait impairment associated with neurogenic claudication (NC) may persist in patients with lumbar spinal stenosis (LSS) even after decompressive surgery. Dynamic sensorimotor alterations during walking may contribute to these impairments. In this case report, we focused on kinesthetic illusion as an exploratory indicator of altered afferent sensory function and describe the clinical course of transcutaneous electrical nerve stimulation (TENS) applied to the abdominal muscles. Case presentation The patient was a man in his 70s who had undergone four-level laminoplasty spanning L1/2 to L4/5 and presented with NC characterized by pain over the lateral aspect of the left lower leg. At the initial assessment, pain rated 8/10 on the Numerical Rating Scale (NRS) limited his walking distance during the 6-minute walk test (6MWT) to 80 m. At that time, an interlimb difference was observed in the kinesthetic illusion of ankle plantarflexion elicited by stimulation of the tibialis anterior (unaffected/affected limb: 4/10). During a subsequent 6MWT performed with TENS applied to the abdominal muscles, pain was rated 3/10, walking distance was 95 m, and the post-walking interlimb difference in the TA-evoked kinesthetic illusion was smaller than that observed after walking without TENS. The patient underwent walking practice combined with abdominal-muscle TENS for 14 days, together with therapeutic exercise. At the outcome assessment, the 6MWT performed without TENS resulted in an NRS pain score of 1/10 and a walking distance of 150 m; the TA-evoked kinesthetic illusion showed no pre-to-post 6MWT change (unaffected/affected limb: 7/10 to 7/10). Conclusions In this patient, abdominal-muscle TENS during walking was temporally associated with lower NC-related pain, greater walking distance, and a smaller post-walking interlimb difference in TA-evoked kinesthetic illusion. Over the 14-day intervention, pain and walking capacity also improved. These findings provide a foundational hypothesis for conducting research that examines the sensorimotor function of patients with LSS using sensory measures, spinal kinematics, and electrophysiological outcomes.