What is the recommended regional block for hip arthroscopy?

Regional Block for Hip Arthroscopy

For hip arthroscopy, a supra-inguinal fascia iliaca compartment block (FICB) is the recommended regional anesthesia technique, as it provides effective analgesia without significant motor weakness that could delay mobilization or increase fall risk.

Evidence-Based Recommendation

The fascia iliaca block is the preferred nerve block for hip surgery based on multiple meta-analyses demonstrating lower pain scores, reduced morphine consumption, and shorter hospital stays without increased risk of falls 1, 2. This recommendation, derived from PROSPECT 2021 guidelines for hip arthroplasty, applies to hip arthroscopy given the similar anatomical innervation patterns 1, 2.

Technical Approach for Hip Arthroscopy

Supra-inguinal FICB technique:

• Use ultrasound guidance to identify echogenic landmarks, which is achievable in 100% of cases 3
• Administer 20-40 mL of 0.25% bupivacaine with epinephrine 1:200,000 for single-dose blocks 4
• For adolescents and older children, use approximately 0.53 mL/kg of 0.2% ropivacaine 3
• The supra-inguinal approach achieves sensory blockade of both femoral and lateral femoral cutaneous nerves in 94% of patients 3

Blocks to Avoid

Femoral nerve block should NOT be used despite its analgesic efficacy, because it causes significant quadriceps weakness that increases fall risk 1, 2, 5. A randomized trial of 50 patients undergoing hip arthroscopy found that 6 patients (22%) in the femoral nerve block group experienced falls within 24 hours postoperatively compared to zero falls in the control group 5.

Lumbar plexus block is NOT recommended due to being a deep block with potential for serious complications, particularly in anticoagulated patients, without demonstrating superior outcomes compared to FICB 1, 6, 2.

PENG (pericapsular nerve group) block cannot be recommended based on the highest quality evidence. A 2022 randomized, double-blind, placebo-controlled trial of 68 patients showed no statistically significant difference in pain scores (mean difference -0.79,95% CI -1.96 to 0.37; p=0.17) or any secondary outcomes including opioid consumption between PENG block and sham injection 7. While case reports suggest potential utility as rescue analgesia 8, the definitive RCT evidence does not support its routine use.

Lateral femoral cutaneous nerve block alone is insufficient, as it only reduced movement-related pain in one study with a 42% non-responder rate 9, and showed no benefit in another study 1.

Critical Timing Considerations

Rebound Pain Phenomenon

When using any regional block for hip arthroscopy, be aware that rebound pain occurs at 24 hours postoperatively as the block wears off 5. This requires:

• Multimodal analgesia with paracetamol and NSAIDs/COX-2 inhibitors started preoperatively and continued postoperatively 6, 4
• Patient education about expected pain increase at 24 hours
• Adequate oral analgesics prescribed for home use

Alternative: Local Infiltration Analgesia

If FICB is not feasible or available, local infiltration analgesia (LIA) is an effective alternative, with five randomized controlled trials showing lower pain scores, reduced opioid consumption, or shorter hospital stays 2, 4. LIA avoids motor blockade entirely and eliminates fall risk associated with lower extremity nerve blocks.

Multimodal Analgesia Framework

Regional blocks should be part of a comprehensive multimodal strategy 6, 4:

• Preoperative paracetamol and NSAIDs/COX-2 inhibitors 6
• Intraoperative dexamethasone 8-10 mg for analgesic and anti-emetic effects 6
• Intraoperative ketamine as co-analgesic 6
• Opioids reserved for rescue analgesia only 6, 4

Common Pitfalls to Avoid

• Do not use infra-inguinal FICB approach, as reported success rates are lower compared to the supra-inguinal technique 3
• Avoid blocks in anticoagulated patients when using deep blocks like lumbar plexus 6
• Do not discharge patients with active motor blockade until quadriceps strength is adequate to prevent falls 5
• Ensure fall precautions are in place for the first 24 hours postoperatively, even with motor-sparing blocks 5