Association between medial calcaneal nerve neuropathy and plantar fasciitis

Abstract Background Plantar fasciitis (PF) is a degenerative condition characterized by repetitive microtrauma at the attachment site of the plantar fascia to the calcaneus leading to heel pain and functional impairment. It has many causes like obesity, flat foot and tight shoes. Recent research has suggested that it may also be associated with neuropathy of the medial calcaneal nerve (MCN), which can cause pain and discomfort in the heel and surrounding areas. The current study aimed to investigate the association between medial calcaneal nerve neuropathy and plantar fasciitis through comparative analysis of nerve conduction study parameters and ultrasonographic measurement of plantar fascia thickness in affected patients and healthy controls. Methodology Thirty patients with clinical and ultrasonographic PF were included as patient group in addition to 30 age and sex-matched healthy individuals as control group. They were subjected to detailed history, thorough clinical examination, ultrasound (US) examination of the foot and nerve conduction studies of MCN in addition to routine posterior tibial motor, sural, medial and lateral plantar sensory conduction studies. Results A highly statistically significant increase in the peak sensory latency (PSL) and highly statistically significant reduced amplitude and decreased conduction velocity (CV) of the sensory response of MCN was found in patients group compared to controls ( P < 0.001). A strong correlation was found between parameters of MCN conduction study parameters and clinical/ultrasonographic features. Conclusion The present study demonstrated a significant relationship between ultrasonographic plantar fascia parameters and MCN conduction findings, supporting a neuro–structural interplay in PF. Specifically, plantar fascia thickness showed a strong positive correlation with MCN peak sensory latency and significant negative correlations with both amplitude and conduction velocity, indicating that increasing fascial thickness is associated with worsening nerve conduction. Similarly, pain severity (VAS score) and duration of heel pain exhibited highly significant correlations with all MCN parameters, reinforcing the link between neuropathic dysfunction and clinical burden. The results suggest that plantar fasciitis extends beyond a purely degenerative fascial disorder, encompassing a neuropathic component reflected by measurable changes in nerve conduction. This underscores the value of integrating both ultrasound and neurophysiological assessments to achieve a more comprehensive evaluation and guide targeted management strategies.