Background: Diabetic neuropathy (DN) refers to signs and symptoms of neuropathy in patients with diabetes in whom other causes of neuropathy have been excluded. Distal symmetrical neuropathy is the most common form accounting for 75 % of DN.
Objective: To determine the pain relief efficacy of three successive ultrasound guided tibial nerve block at the ankle with bupivacaine and betamethasone, as a primary outcome in the management of chronic painful diabetic neuropathy of the foot resistant to medical management, compared to ultrasound guided placebo tibial nerve block. Serum glucose levels for assessment of diabetes control and patients satisfaction were measured as a secondary outcome.
Patients and Methods: After obtaining the Ethics Committee's approval of Anesthesia Department of Al-Zahra'a University Hospital, and the patients' written informed consent, 40 Patients (aged 18-60y) with chronic painful distal diabetic polyneuropathy were prospectively enrolled in this double blind and random study. The patients were classified randomly into two equal groups: Group (I): Control group: patients who received ultrasound guided tibial nerve injection by sterile cold normal saline (28 C), and Group (II): Steroid group: Patients received ultrasound guided tibial nerve injection by betamethasone (7mg amp) which was diluted in 7ml saline, then 1mg was diluted in 0.25% bupivacaine. Each limb was injected in both groups by three successive injections each other week in alteration with other limb, then followed up monthly for 3 months.
Results: Three successive ultrasound guided tibial nerve block at ankle level with 1mg betamethasone in 0.25% bupivacaine decreased LANSS score and analgesic requirements with more patient satisfaction in distal painful diabetic neuropathy resistant to medical treatment.
Conclusion: The therapeutic benefits provided by ultrasound guided tibial nerve block with bupivacaine and betamethasone more effective than placepo block. Pain and other symptoms decrease abruptly after the first tibial nerve block and disappear after the third tibial nerve block.