Femoral Triangle and Adductor Canal Blocks Versus Femoral Nerve Block for Total Knee Arthroplasty
Condition: Total Knee Arthroplasty
Study type: Interventional

Summary: 
      This prospective, double-blinded, randomized controlled study evaluates effects of femoral
      triangle and adductor canal blocks in comparison with femoral nerve block for primary total
      knee arthroplasty. Patients undergoing primary total knee arthroplasty will be randomly
      assigned to receive either femoral triangle and adductor canal blocks or femoral nerve block.
      Comparison of these two groups of patients will be based on the effects on postoperative pain
      control, extent of motor blockade, ability of early ambulation, patients satisfaction rates
      over the time of clinical recovery and the length of hospitalization.

      To the investigator's knowledge, no comparison has been made between femoral triangle and
      adductor canal blocks and femoral nerve block or any other block. Consequently, we
      hypothesized that femoral triangle and adductor canal blocks and femoral nerve block provide
      similar effects on postoperative pain control, but femoral triangle and adductor canal blocks
      are superior to femoral nerve block in terms of early postoperative mobilization.
    

Detailed description: 
      The aim: to evaluate femoral triangle and adductor canal blocks and femoral nerve block
      regarding the postoperative analgesic efficacy, extent of motor blockade, ability of early
      ambulation in patients following primary total knee arthroplasty.

      Primary Hypothesis: femoral triangle and adductor canal blocks and femoral nerve block
      provide similar postoperative pain relieving effect after primary total knee arthroplasty.

      Secondary Effects: femoral triangle and adductor canal blocks provide better ability of early
      ambulation after primary total knee arthroplasty.

      The objectives:

        1. To compare postoperative pain control effects between femoral triangle and adductor
           canal blocks and femoral nerve block groups of patients after primary total knee joint
           replacement surgery.

        2. To assess the ability of early ambulation and extent of motor blockade after primary
           total knee joint replacement surgery between the groups of patients.

        3. To estimate opioid consumption and its adverse effects in femoral triangle and adductor
           canal blocks and femoral nerve block groups of patients after primary total knee
           arthroplasty.

        4. To compare patients postoperative satisfaction rates between femoral triangle and
           adductor canal blocks and femoral nerve block groups of patients after primary total
           knee arthroplasty.

      Methods:

      The prospective, double-blinded study includes American Society of Anesthesiologists (ASA)
      physical status I-III in preoperative assessment, aged 18-90 years, admitted for primary
      total knee arthroplasty. Preoperatively patients will be blindly randomized into one of two
      groups: femoral triangle and adductor canal blocks group and femoral nerve block group. Group
      assignment will be concealed by opaque envelopes that will be opened only after the
      enrollment. The anesthesiologist performing the block will be aware of the treatment, but the
      participant and outcomes assessor will be blinded to the group assignment.

      All blocks will be performed by the anesthesiologist under the guidance of a linear
      ultrasound transducer probe. Femoral nerve block will be performed at the proximal part of
      the femoral triangle by 20 mL of 0.125% bupivacaine injection. Femoral triangle and adductor
      canal blocks will be performed together. Femoral triangle block will be performed at the
      level where the medial border of the sartorius muscle intersects the medial border of the
      adductor longus muscle with injection of 10 mL of 0.125% bupivacaine. Local anesthetic will
      be injected laterally to the femoral artery. Adductor canal block will be performed at the
      level where the femoral vessels (artery and vein) dive deeper from the sartorius muscle with
      injection of 10 mL of 0.125% bupivacaine. Local anesthetic will be injected under the femoral
      artery.

      During the perioperative period all patients from both groups will receive a standardized
      anesthetic and analgesic. Premedication of midazolam 2.5-5 mg and dexamethasone 4 mg will be
      given to all patients and a slow fluid infusion of crystalloids with 1 g of tranexamic acid
      and 10 mg of ketamine will be started once as an intravenous cannula will be placed. Spinal
      anesthesia after identification of the subarachnoid space will be performed with 15 mg of
      levobupivacaine. After that, femoral triangle and adductor canal blocks or femoral nerve
      block (depending on the group of patients) will be performed under the ultrasound guidance.
      Patients will be sedated with intravenously administered propofol during the surgery. The
      local infiltration analgesia will be performed by the surgeon at the end of surgery with
      combination of 30 mL of 0.5% bupivacaine, 0.3 mL of 0.1% adrenaline and 90 mL of 0.9% sodium
      chloride. After the surgery patients will be transferred to the post-anesthesia care unit
      (PACU).

      During the postoperative period for analgesia NSAIDs will be available to both groups of
      patients. NSAIDs such as dexketoprofen 50 mg will be administered 2 times and acetaminophen 1
      g will be administered 3 times per day. Opioids will also be available to patients as
      intramuscular boluses of pethidine 50 mg or morphine 10 mg without restriction and
      administered for moderate or severe pain (VAS pain score of 5 or greater out of 10).

      Postoperative pain control efficacy will be assessed at 3, 6, 24 and 48 hours after surgery
      using visual analogue scale (VAS) from 0 to 10 (0 - no pain, 10 - worst imaginable pain) at
      rest, during active and passive 45 degree knee flexion. The requirement of additional
      analgesics and their adverse effects (if any) will be recorded.

      The extent of motor blockade will be evaluated at 3, 6, 24, 48 hours after surgery. Patients
      will be asked to flex the foot, to flex the knee and to lift up the straight leg. The
      possible leg motion at 3, 6, 24 and 48 hours postoperatively will be assessed with Bromage
      scale grades: Grade I - free movement of legs and feet, Grade II - just able to flex knees
      with free movement of feet, Grade III - unable to flex knees, but with free movement of feet,
      Grade IV - unable to move legs or feet.

      Patients ability of early ambulation will be evaluated using Timed Up and Go (TUG) test at 24
      and 48 hours after surgery. To do the TUG test, patients will have to sit down on the bed,
      get up from the bed, walk 3 meters forward, turn, walk back 3 meters to the bed and sit down.
      The time taken by a patient to perform this test will be calculated with a chronometer.

      After the conversation with each patient and assessment of postoperative pain control
      efficacy, extent of motor blockade, ability of early ambulation, the rate of patient
      satisfaction will be evaluated using a 10 point scale from 0 (completely unsatisfied) to 10
      (totally satisfied) at 3, 6, 24, 48 hours after surgery.

      The length of hospital stay and rate of complications (if any), including falls, local
      anesthetic toxicity or neurological complications, will be recorded in both groups of
      patients.

      According to study protocol, both groups of patients will be compared in terms of
      postoperative pain control, opioid consumption, extent of motor blockade, ability of early
      ambulation, patients satisfaction rates over the time of clinical recovery and the length of
      hospitalization.
    

Intervention name(s): Femoral Nerve Block; Femoral Triangle & Adductor Canal Blocks
Intervention type(s): Procedure; Procedure
Intervention description(s): Procedure: Femoral Nerve Block
The femoral nerve block will be performed as described in Arms section.
Device: Ultrasound
Linear ultrasound transducer probe (Flex Focus 400 exp, bk medical, Denmark) will be used to guide the needle placement.
Device: Needle
20-gauge 50 mm Ultraplex needle (B. Braun Medical Inc., Melsungen, Germany) will be used to perform the femoral nerve block.
Drug: Local anesthetic
Bupivacaine 0.125% 20 mL will be used to perform the femoral nerve block.; Procedure: Femoral Triangle & Adductor Canal Blocks
These two blocks will be performed as described in Arms section.
Device: Ultrasound
Linear ultrasound transducer probe (Flex Focus 400 exp, bk medical, Denmark) will be used to guide the needle placement.
Device: Needle
20-gauge 100 mm Ultraplex needle (B. Braun Medical Inc., Melsungen, Germany) will be used to perform the femoral triangle block and adductor canal block.
Drug: Local anesthetic
Bupivacaine 0.125% 20 mL will be used to perform the femoral triangle block and adductor canal block (10 mL for each block).
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Femoral triangle block; Adductor canal block; Femoral nerve block; Primary total knee arthroplasty; Pain management; Functional recovery