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Quadratus Lumborum Block for Total Hip Arthroplasty


Brief Summary

The quadratus lumborum (QL) block is a fascial plane block primarily used to provide pain relief in abdominal surgeries. Most literature on the QL block focuses on pain control after lower abdominal, urologic (urinary tract system) or gynecologic (reproductive system) surgeries, however, its pain relief coverage has been described as wide as T7-L3 dermatomes (pain relief that extends from the lower chest to the knee) and as such, may prove applicable in lower extremity surgeries such as the total hip arthroplasty (THA, a surgical procedure performed to restore function of the hip joint). Further investigation regarding the efficacy of QL blocks in patients undergoing primary THA under spinal anesthesia (a procedure that numbs from the waist down) would be of value, particularly as there is a push towards opioid-sparing analgesia (pain relief that minimizes the use of opiates) and reducing hospital length of stay, something that can be minimized with better patient pain control after surgery. The investigators aim to evaluate the efficacy of ultrasound guided QL nerve blocks as a method of analgesia (pain relief) for patients undergoing primary THA.

Patients will be randomized to receive a QL nerve block with either saline or ropivacaine (a local anesthetic) prior to their surgical procedure. The QL nerve block procedure will take between 3 and 10 minutes of the patient's time. During this procedure the patient will be made comfortable either with local anesthetic medication or IV anti-anxiety medications. During the QL nerve block procedure patients will be asked to receive an injection that is placed on the side of their abdomen, between layers of their flank muscles. The injection is placed using the guidance of an ultrasound machine. Postoperative outcomes assessed will include: pain score, amount of opioid pain medications taken, distance of first ambulation (walking without assistance), length of hospital stay, and patient satisfaction. Outcomes will be assessed at 3hrs, 12hrs, 24hrs, and 48hrs after the surgical procedure ends and will be assessed by a combination of medical record review and by survey. Patients will be surveyed by phone call or in-person visit to the patient's room. Each assessment encounter should take between 1 and 5 minutes. Participants will be involved in the study through the 48 hour follow-up period and total time required from patients will range from 7 minutes to 30 minutes.

Primary Purpose
Study Type
Early Phase 1


Healthy Volunteers
Minimum Age
18 Years
Maximum Age

Inclusion Criteria:

  • Adult patients undergoing elective primary total hip arthroplasty for osteoarthritis by a single surgeon.

Exclusion Criteria:

  • patients age < 18,
  • documented allergy to local anesthetic,
  • presence of peripheral neuropathy,
  • patients with current long term opioid use defined as receiving an opioid on most days in a 90 day period, and
  • patients with a contraindication to spinal and regional anesthesia such as coagulopathy or infection at the site of the regional technique.
  • Additionally, patients who receive general anesthesia during the surgery, either as part of the planned anesthetic (at the discretion of the patient's assigned anesthesiologist) or as a rescue anesthetic after a failed spinal, will be excluded from the study. More specifically, if a patient is found to be moving their lower extremities or showing signs of sensation in the lower extremities 15 minutes after the spinal procedure is performed, this would be considered a failed spinal. In the case of a failed spinal, general anesthesia would be required to continue with surgery. After detection of a failed spinal, the anesthesiologist would make a determination about the safety of proceeding with general anesthesia versus aborting the surgery. If safe and consented for, or if emergent general anesthesia is required, the patient would be induced (given medications to begin) general anesthesia in a manner appropriate for the individual patient, taking into account their body habitus and medical history. Any patient who undergoes general anesthesia, including those for whom it is used as a rescue anesthetic as described, will be excluded from the study.

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Study Stats
Protocol No.
Anesthesiology & Perioperative Medicine
  • UCLA Santa Monica
For Providers
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