Ultrasound Guided Adductor Canal Versus Femoral Nerve Blocks for Anterior Cruciate Ligament Reconstruction in Pediatrics
Condition: Post-operative Pain; Quadriceps Muscle Strength
MeSH terms: Pain, Postoperative
Study type: Interventional

Summary: 
      Both Ultrasound guided Adductor Canal Block ( ACB) and Femoral Nerve Block (FNB) has been
      used to provide postoperative analgesia for knee surgeries. To the investigators' knowledge,
      no comparison has been made between those blocks in relation to postoperative quadriceps
      muscle strength, or duration and quality of postoperative analgesia for arthroscopic ACL
      reconstruction in pediatrics. If ACB provides postoperative analgesia after arthroscopic knee
      surgery comparable to FNB, it has the potential to improve the postoperative outcome as it
      will lead to less quadriceps muscle weakness and early mobilization, both of which are very
      important in the early postoperative period.
    

Detailed description: 
      Motor preservation with adequate analgesia has become the optimal postoperative goal in
      orthopedic surgeries, in particular knee surgeries. This enables earlier physical therapy,
      faster recovery and shorter hospital stays. Both Ultrasound guided ACB and FNB has been used
      to provide postoperative analgesia for knee surgeries, including anterior cruciate ligament
      reconstruction . To the investigators' knowledge, no comparison has been made between both
      blocks in relation to postoperative quadriceps muscle strength as well as duration and
      quality of postoperative analgesia for arthroscopic ACL reconstruction. ACB predominantly
      block the sensory component of the femoral nerve without much effect on the motor component.
      Hence, it can lead to less quadriceps muscle weakness, early postoperative mobilization and
      decreases the incidence of postoperative fall . With the advent of ultrasonography, the
      adductor canal can be easily visualized at the mid-thigh level, allowing performance of ACB
      with a high success rate . In recent years, ACB has been successfully used for postoperative
      pain control after knee surgery . Anatomical study of adductor canal demonstrated that the
      adductor canal may serve as a conduit for more than just the saphenous nerve, possibly
      including the vastus medialis nerve, medial femoral cutaneous nerve, articular branches from
      the obturator nerve, as well as the medial retinacular nerve . Thus, the sensory change is
      not limited to the distribution of the saphenous nerve but includes the medial and anterior
      aspects of the knee from the superior pole of the patella to the proximal tibia.To the
      investigators Knowledge there has not been a randomized controlled study comparing ACB with
      FNB after Arthroscopic Anterior Cruciate Ligament (ACL) reconstruction. This prospective,
      double-blinded, randomized, controlled study will test the hypothesis that ACB would be
      associated with less quadriceps motor weakness than FNB at 4 hours after block performance .
      The investigators also hypothesize that ACB will provide analgesia to the anterior knee that
      is not inferior to FNB and not different in opioids usage at 4 and 24 hours after Peripheral
      Nerve Block (PNB) performance .

        -  Hypothesis ACB would be associated with less quadriceps motor weakness than FNB and
           provide postoperative analgesia comparable to FNB in quality and duration as determined
           by Numeric Scale (NS) pain scores and opioid use a 4 and 24 hours after PNB.

        -  Objectives

      To compare FNB and ACB regarding:

        1. Quadriceps muscle strength at 4 hours after PNB performance.

        2. Pain scores at anterior knee at 4 hours and 24 hours after PNB as assessed by Numeric
           Scale (NS) pain scoring system. Also pain site other than the anterior knee will be
           recorded and specified (posterior knee, calf, leg)

        3. Total opioid consumption at 4 and 24 hours after PNB.

             -  Study Design:

      Randomized, double blinded, single center clinical trial. A total of 52 pediatric patients
      (ASA 1or 2), aged between 8 to 18 years, for elective ACL reconstruction at Akron Children's
      Hospital ( ACH ) will be enrolled in the study. Patients will be randomly assigned to one of
      two groups, A or B. Group A (26 patients) will have ultrasound guided ACB performed at
      mid-thigh level and group B (26 patients) will have ultrasound guided FNB, with nerve
      stimulator confirmation with the type of motor response (e.g., quadriceps, patellar) and the
      minimum current needed to be recorded. Both blocks will be performed under general
      anesthesia. Both group will have ropivacaine 0.2 % ( 0.5 ml/kg, maximum of 30 ml and
      methylprednisolone acetate 1 mg/kg , maximum of 40 mg ).Both blocks will be performed using a
      22-gauge 2-inch Stimuplex A needle; ; B. Braun Medical Inc., Melsungen, Germany).Both blocks
      will be performed using linear ultrasound transducer, General Electric ( GE). Ultrasound
      pictures will be obtained to Verify proper local anesthetic placement.Unfortunately, surgeons
      are not able to determine the type of procedure needed to correct ACL injury, until after
      knee arthroscopy is performed under general anesthesia. ACL reconstruction using a hamstring
      graft, which is the surgical procedure used in this study may not always be possible to
      perform by the surgeon. The surgical alternative of ACL reconstruction , is ACL repair, which
      seldomely is done by our surgeon. Patient undergoing ACL reconstruction can experience pain
      in the posterior aspect of the knee, in the distribution of the siatic nerve. This is due to
      the hamstring graft. In contrast to the anterior knee pain covered by both ACB and FNB,
      posterior knee pain is controlled with IV/oral analgesic. This is why recording the site of
      the knee pain is important to determine the PNB success. . Due to the inability to determine
      beforehand, the type of procedure to be performed, we decided therefore to continue the study
      procedures and data collection on both ACL reconstruction and ACL repair. The statistical
      analysis will include only patients that undergo ACL reconstruction. For the other patients
      that undergo ACL repair , data will be collected but not included in the statistical
      analysis. The data from these patients may be used as a pilot for future research.

      Quadriceps strength of both legs will be assessed by placing the dynamometer on the anterior
      of the ankle, between the malleoli. Patients will be instructed to extend their legs three
      times each, with a 30 seconds pause between each attempt as described by Maffiuletti . The
      assessment will be performed in the pre-operative period and will be repeated postoperatively
      at 4 hours after PNB. All patients will be observed in the post-operative period by an
      observer unaware of the technique of analgesia used. Pain will be assessed using the NS.
      Postoperatively, PCA morphine pumps will be attached to patients. A loading dose of 0.05
      mg/kg to a maximum of 5 mg will be administered in the Post Anesthesia Care unit (PACU) as
      needed, followed by demand interval dosing of 0.015 mg/kg every 10 minutes.as demanded by the
      patient .Four-hours limits for morphine will be set at 0.35 mg/kg. No continuous infusion and
      no adjuvant NSAIDs or acetaminophen will be administered. Rescue morphine dosing will be
      ordered via PCA pump at 0.05 mg/kg ( repeated once as needed) and will be available every two
      hours as needed by pain assessment ( for a NS ≥ 4 ) or patient request. Diazepam 0.03 mg/kg
      IV will be available every 4 to6 hours as needed for muscle spasm or anxiety. Patients will
      be considered ready for discharge from hospital when all the following criteria are met:
      Child is alert, oriented, stable vital signs, and would tolerate clear liquid, with no nausea
      or vomiting and good pain control. The evaluation for meeting the discharge criteria will be
      done after one hour from arrival in PACU and every 30 minutes thereafter till the patient
      meet all the discharge criteria. After discharge, After discharge, parents will be instructed
      to give the child oxycodone tablets/elixir 0.1 mg /kg PO q 3 hours as needed for pain. In
      addition, acetaminophen 10mg/kg q 4 hours PRN up to a maximum of 3 gm and/or ibuprofen 10
      mg/kg q 6 hours PRN up to maximum of 2400 mg/24 hours, may be administered for any residual
      pain. The total dose of oxycodone, ibuprofen and tylenol will be recorded per parents for a
      total of 24 hours after PNB. Pain scores will be also recorded by parent at rest,24 hours
      post -block. The data for total opioids use in the first 24 hours after PNB and pain score at
      24 hours will be collected from parent by phone call.

        -  Study Endpoints

           1-Quadriceps muscle strength at 4 after PNB 2- Total morphine/morphine equivalent at 4
           and 24 hours after PNB. 3-Pain scores at anterior knee at 4 hours and 24 hours after PNB
           as assessed by Numeric Scale (NS) pain scoring system. Also pain site other than the
           anterior knee will be recorded and specified (posterior knee, calf, leg).

        -  Method for Assigning Subjects to Treatment Regimen Random allocation for one of the two
           treatments will be achieved using sealed envelope assigned by external third party not
           involved in the study to ensure allocation concealment.

        -  Study Monitoring Plan This study will be monitored through a data monitoring committee.
           The study will be performed over a period of 18-24 months. This study offers minimal
           risk to the patient. The data monitoring committee will include the PI, at least one of
           the co-investigators, the principal statistician, and the principal research nurse.

      The data monitoring committee will meet when approximately 25%, 50%, 75% and 100% of the
      primary outcomes are observed. The priority of the data monitoring committee will be to
      ensure the safety of the participants in the trial and to ensure the integrity of the trial.
      Also, these meetings will monitor the quality of the collected data to assess for weaknesses
      and errors. If any weakness and/or errors are identified, feedback will be provided during
      these meetings .The investigator(s) will allocate adequate time for such monitoring
      activities. The investigator(s) will also ensure that the monitor or other compliance or
      quality assurance reviewer is given access to all the above noted study-related documents.

      -Summary Statistics: Will be provided for all variables. Examination of continuous data will
      include normality testing as well as assessment of potential outliers. Statistical testing
      will be based upon distributional shape, but for purpose of analytical planning and sample
      size analysis normality of distributions will be assumed.

      To examine for potential differences in quadriceps motor strength (QMS) between the two
      groups (ACB, FNB) quadriceps strength will be assessed at the four hour time point (assuming
      no evidence in sample of baseline or pre-operative differences). Non-inferiority of ACB to
      FNB in analgesia provided will be assessed by examination of pain scores. Non-inferiority of
      ACB compared with FNB is defined as the mean ACB - NRS pain score not higher than the mean
      FNB - NRS pain score by an amount of 1.6. (Kim, 2014) Pain scores will be individually
      examined at the 4 hour and 24 hour post - operative time points with appropriate Bonferroni
      adjusted alpha. In addition, a change in pain score from 4 to 24 hours will be created and
      evaluated for potential difference between groups.

      Total opioid consumption as measured in morphine equivalents will be assessed at the 24 hour
      post-operative time point to determine whether a difference exists. Opioid consumption will
      also be examined by creating a change score from 4 to 24 hour consumption and comparing
      between the groups.

      All testing will be completed utilizing SAS 9.4 © software and evaluated at the Type I Error
      Rate of alpha = 0.05 level for statistical significance unless otherwise noted.
    

Intervention name(s): Adductor Canal Block; Femoral Nerve Block; Ultrasound; Stimuplex A needle; local anaesthetic injection; Steroid Drug
Intervention type(s): Procedure; Procedure; Device; Device; Drug; Drug
Intervention description(s): Under guidance of a linear ultrasound transducer probe (General Electric; GE). Performed using a 22-gauge 2-inch Stimuplex A needle ( B. Braun Medical Inc., Melsungen, Germany).Solution to be injected will be a combination of Ropivacaine 0.2 % ( 0.5 ml/kg, maximum of 30 ml) and methylprednisolone acetate 1 mg/kg ( maximum of 40 mg ).; Under guidance of a linear ultrasound transducer probe (General Electric;GE).Block will be performed using a 22-gauge 2-inch Stimuplex A needle ( B. Braun Medical Inc., Melsungen, Germany).Solution to be injected will be a combination of Ropivacaine 0.2 % ( 0.5 ml/kg, maximum of 30 ml) and methylprednisolone acetate 1 mg/kg (maximum of 40 mg ).; Use of linear ultrasound transducer probe (General Electric;GE) to guide needle placement for both Adductor Canal Block and Femoral nerve Blocks; 22-gauge 2-inch Stimuplex A needle ( B. Braun Medical Inc., Melsungen, Germany) used to perform both Adductor Canal Block and Femoral nerve Blocks.; Ropivacaine 0.2 % ( 0.5 ml/kg, maximum of 30 ml) for either Adductor Canal Block and Femoral nerve Blocks.; Methylprednisolone acetate 1 mg/kg (maximum of 40 mg ) for either Adductor Canal Block and Femoral nerve Blocks.
Intervention MeSH terms: Anesthetics; Anesthetics, Local
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Outcomes Assessor)
Primary purpose: Other
Keywords: Quadriceps muscle strength; Anterior cruciate ligament reconstruction; Femoral nerve block; Adductor Canal block; Saphenous nerve block in the Adductor Canal; Pediatrics; Postoperative analgesia; Ultrasound guided nerve block