The Effect of Subsartorial Saphenous Block on Postoperative Pain Following Major Ankle and Hind Foot Surgery

The Effect of Subsartorial Saphenous Block on Postoperative Pain Following Major Ankle and Hind Foot Surgery

The study investigates the effect of a ultrasound-guided subsartorial saphenous block on postoperative pain following major ankle and hind foot surgery.

Major ankle and hind foot surgery causes intense postoperative pain. Implementation of continuous sciatic catheters has been a great success in reducing postoperative pain following these operations, but despite an effective sciatic catheter patients still report moderate to severe pain from the anteromedial side of the ankle. According to cadaver dissection studies the saphenous nerve innervates the anterior and medial parts of the ankle and talonavicular joint, and even though a saphenous block is standard procedure in many departments of anesthesiology worldwide, scientific evidence regarding the effect of the saphenous block on postoperative pain is lacking.

This study investigates the effect of a selective, ultrasound-guided subsartorial saphenous block on postoperative pain following major ankle and hind foot surgery.

Inclusion Criteria:

• Elective ankle or hind foot surgery either: (1) total ankle arthroplasty, (2) ankle arthrodesis (3) subtalar arthrodesis or (4) triple arthrodesis
• Age ≥ 18
• American Society of Anaesthesiology Classification I-III
• Informed consent both orally and in writing after the patient has fully understood the protocol and its limitations.

Exclusion Criteria:

• Communication problems or dementia
• Allergies to any medical product used in the study
• Neuropathy of the sciatic or femoral nerve prior to the operation
• Morbus Charcot-Marie-Tooth disease, diabetic neuropathy, peripheral vascular disease
• Daily use of opioids
• Coagulation disorders
• Infection at the site of injection or systemic infection