Ultrasound-Guided Pulsed Radiofrequency Added to Perineural Steroid Injection Versus Perineural Steroid Injection Alone in the Treatment of Tarsal Tunnel Syndrome

Tarsal tunnel syndrome (TTS) is an entrapment neuropathy caused by compression of the posterior tibial nerve at the ankle, resulting in pain, numbness, and tingling sensations in the heel and sole of the foot. Perineural steroid injections under ultrasound guidance are commonly used for conservative management to decrease inflammation and relieve pressure. Pulsed radiofrequency (PRF) is a minimally invasive neuromodulatory technique that delivers electrical pulses to alter pain transmission and promote tissue healing without damaging the nerve structure. The objective of this prospective, randomized, double-blind clinical trial is to determine whether combining ultrasound-guided pulsed radiofrequency with perineural steroid injection provides superior pain relief, improved foot function, and higher patient satisfaction compared to perineural steroid injection alone in patients with mild-to-moderate tarsal tunnel syndrome. A total of 50 adult participants will be randomly allocated to one of two study groups: * Group A (Active PRF + Steroid Injection): Participants receive ultrasound-guided pulsed radiofrequency applied adjacent to the posterior tibial nerve for 8 minutes (480 seconds), followed immediately by a perineural injection of 10 mL solution containing triamcinolone acetonide, dextrose 5%, and lidocaine 1%. * Group B (Sham PRF + Steroid Injection): Participants undergo identical ultrasound-guided needle positioning and sensory/motor stimulation testing, followed by 8 minutes of sham radiofrequency (generator switched off), and then receive the identical 10 mL perineural steroid injection. Participants will be evaluated prior to the procedure and at 2 weeks, 1 month, 3 months, and 6 months post-intervention to assess pain severity (Visual Analogue Scale), foot function and disability (Foot Function Index), global impression of recovery, and any procedure-related side effects or complications.

Inclusion Criteria: * Adult patients aged 18 to 65 years old. * Clinical diagnosis of idiopathic tarsal tunnel syndrome (TTS). * Abnormal electrophysiological study confirming mild-to-moderate TTS. * Pain or paresthesia in the posterior tibial nerve distribution persisting for more than 6 months and refractory to conservative therapy (e.g., vitamin B complex, NSAIDs, oral steroids, or night splints). * Positive Tinel's sign and/or positive triple compression test. * Patient is willing and able to provide written informed consent and attend all scheduled follow-up visits. Exclusion Criteria: * Severe TTS (defined by abductor hallucis muscle atrophy, distal motor latency \> 6.5 ms, or absent potentials on electrophysiological testing). * Prior ankle or tarsal tunnel injection within the preceding 3 months. * Secondary tarsal tunnel syndrome due to systemic diseases (e.g., endocrine disorders, rheumatoid arthritis, gout, or psoriatic arthritis). * Concurrent use of systemic corticosteroids or antihistamines. * Presence of coagulopathy. * Local infection at the planned injection site. * Known allergy or hypersensitivity to any of the study medications (triamcinolone acetonide, lidocaine, or dextrose). * Pregnancy or lactation. * Patient refusal to participate.