Single Dose Adductor Canal Block vs SPANK Block for TKA

Single Dose Adductor Canal Block With SPANK (Sensory Posterior Articular Nerves of the Knee) Block Compared to Single Dose Adductor Canal Block and Pain Control After Total Knee Arthroplasty

This is a prospective, randomized control trial to compare SPANK block combined with adductor canal block to adductor canal block alone in treatment of post-operative pain after total knee arthroplasty. The primary outcome is pain control, which will be measured throughout the post-operative course using morphine equivalents of opioid analgesics used during the first 24 hours after surgery. Secondary outcomes include pain scores recorded at 4, 8, 12, 16, 20, and 24 hours post-operatively, cumulative pain score, incidence of post-operative nausea and vomiting, and extent of motor blockade. The study will aid in answering the question of whether SPANK block is an effective adjunct in preventing pain and decreasing opioid requirement after TKA.

Inclusion Criteria:

• Patients between the ages of 40 and 80 years old undergoing total knee arthroplasty amenable to peripheral nerve block for perioperative analgesia.
• BMI <45
• ASA class III or less

Exclusion Criteria:

• Inability to sign consent form
• Allergy to medications used in the study
• Repeat surgery
• History of seizure disorder
• Simultaneous bilateral TKA
• History of substance abuse
• BMI >45
• Opioid consumption of greater or equal to 30mg morphine equivalents per day
• Age <40 or >80 years old
• ASA IV or greater
• Inability to use a PCA
• Inability to access the intrathecal space
• Infection at the site of injection (either for spinal or PNB)
• INR greater than or equal to 1.4