Abstract
Category:
Hindfoot; Other
Introduction/Purpose:
Heel pain is one of the most common presentations encountered by foot and ankle specialists. While most etiologies of heel pain such as plantar fasciitis are mechanical stress driven nociceptive pain, a combined neuropathic mechanism may contribute to worse outcomes and challenges in pain management for a subset of these patients. Diagnosis and management of neuropathic pain in foot and ankle patients remain challenging. Since neuropathic pain may play an important part in indicating surgery or counseling heel pain patients, we investigated the plausibility of utilizing the Patient-Reported Outcomes Measurement Information System (PROMIS) Neuropathic Pain Quality (PQN) as an initial screening tool to diagnose and monitor the clinical effects of treatment. Secondary outcomes were prevalence of neuropathic pain and associated risk factors.
Methods:
New patients presenting to a tertiary care academic institution with heel pain were prospectively recruited. PROMIS PQN t-scores were obtained from all patients to detect and determine the severity of NP. Patients were grouped into no neuropathic pain (NP), mild neuropathic pain (NP), and severe NP based on the initial PROMIS PQN t-scores. Pain Interference (PI), Physical Function (PF), and Self-Efficacy (SE) scores were assessed at baseline, 30, and 90-day follow-up timepoints. Other factors such as age, smoking, body mass index (BMI), low back/neck pain, anxiety, depression, and medications were analyzed for association with outcomes. Linear mixed modeling was utilized to assess the main effects of time and NP on PROMIS t-scores, and meaningful clinically important difference (MCID) was compared.
Results:
A total of 48 patients with mean age of 52.4+-12.5 years old were recruited at the initial visit. The cohort consisted of 35 (73%) female patients, 7 (15%) diabetics, 6 (13%) current smokers, 18 (38%) with low back/neck pain, 6 (13%) with anxiety, 15 (31%) with depression, and 9 (19%) had taken neuromodulator, such as gabapentin. When using the PROMIS PQN as the assessment tool, 33 patients (69%) had NP at baseline; 23 (48%) with mild, and 10 (21%) with severe NP. BMI was the only significant independent factor associated with NP (p = 0.011). Higher baseline NP was significantly associated with higher PQN (p<0.001) and PI (p=0.005), and lower SE (p=0.04) across timepoints. Patients who were detected to have NP based on the PQN t-score had lower PF at baseline with significantly less improvement in PF (3 vs 9.9, p=0.035), and did not meet MCID (Figure 1).
Conclusion:
Prevalence of neuropathic pain in patients presenting with heel pain was high. Neuropathic pain at baseline was significantly associated with worse pain and self-efficacy over time, and less clinically meaningful improvements in function. The PROMIS PQN may serve as a valuable tool to identify and guide clinical treatment decision pathways for patients with neuropathic heel pain.
