Is a pericapsular nerve group (PENG) block effective for post-operative pain management following hip arthroscopy with labral repair?

PENG Block for Post-Operative Pain Management After Hip Arthroscopy with Labral Repair

Direct Recommendation

The PENG block is not recommended for post-operative pain management following hip arthroscopy with labral repair, as current guidelines classify it as having insufficient evidence for all indications, and the highest quality randomized controlled trial specifically in hip arthroscopy patients showed no analgesic benefit. 1, 2

Evidence-Based Rationale

Guideline Position on PENG Block

• Major procedural-specific pain management guidelines for hip surgery do not include PENG block among recommended regional anesthetic techniques. 1
• The PROSPECT guidelines for total hip arthroplasty—the most comprehensive procedure-specific pain management guidelines—make no mention of PENG block in their recommendations. 3
• PENG block is explicitly listed as having "insufficient evidence" for all indications because the effectiveness of this approach has not been established. 1

Highest Quality Evidence Specific to Hip Arthroscopy

• A 2022 randomized, double-blinded, placebo-controlled trial in hip arthroscopy patients (the exact procedure in question) demonstrated that preoperative PENG block does not improve analgesia following arthroscopic hip surgery. 2
• This study found no statistically significant difference in worst pain scores within 30 minutes of emergence (mean difference -0.79,95% CI -1.96 to 0.37; p=0.17). 2
• No secondary outcomes showed statistically significant differences between PENG and sham groups, including opioid consumption, patient satisfaction, or adverse events. 2

Supporting Meta-Analysis Evidence

• A 2023 systematic review and meta-analysis of nine randomized controlled trials found no significant difference in 24-hour morphine consumption (MD: -2.57,95% CI: -5.42 to 0.27, P = 0.08) between PENG block and control groups. 4
• The meta-analysis showed no significant difference in pain scores at 6 hours or 24 hours postoperatively, either static or dynamic. 4
• The time to first request for rescue analgesia was not significantly different (MD: 1.79,95% CI: -1.06 to 4.64, P = 0.22). 4

Context: Different Surgical Procedures

• While one 2025 study in anterior total hip arthroplasty showed reduced length of stay with PENG block, it found no significant difference in pain scores or morphine consumption—and this was for a different surgical procedure (arthroplasty vs. arthroscopy). 5
• Most available literature has evaluated PENG block for hip fracture management rather than hip replacement or arthroscopic surgery. 6

Recommended Alternative Approaches

First-Line Regional Techniques for Hip Surgery

• Fascia iliaca block is the preferred nerve block when regional technique is indicated for hip surgery, with demonstrated lower pain scores, reduced morphine consumption, and shorter length of stay without increased fall risk. 6
• Single-shot fascia iliaca block is specifically recommended by PROSPECT guidelines for total hip arthroplasty. 3
• Local infiltration analgesia (LIA) is another recommended option that has shown benefits in pain control during the first 24 hours postoperatively. 6

Multimodal Analgesia Foundation

• Basic analgesic regimen should include paracetamol combined with an NSAID or COX-2-selective inhibitor, administered pre-operatively or intra-operatively and continued postoperatively. 3, 6
• Single intra-operative dose of intravenous dexamethasone 8-10 mg is recommended for analgesic and anti-emetic effects. 3
• Opioids should be reserved as rescue analgesics in the postoperative period. 3

Techniques to Avoid

• Femoral nerve block should be avoided due to significant incidence of muscle weakness that can delay mobilization. 6
• Lumbar plexus block is not recommended as it is a deep block with potential risks and adverse effects that outweigh benefits. 3, 6

Clinical Pitfalls and Caveats

Risk of Unproven Techniques

• Using unproven techniques like PENG block may delay implementation of more effective pain management strategies, potentially leading to inadequate pain control. 1
• The PENG block has a risk of inadvertent femoral nerve block if the probe or needle is out of plane, which could cause the motor weakness you are trying to avoid. 7

Distinguishing Editorial Opinion from Evidence

• While a 2024 editorial commentary suggests PENG block "has been shown to decrease acute postoperative pain" in hip arthroscopy, this represents expert opinion rather than guideline-level evidence, and contradicts the actual randomized controlled trial data. 7
• The editorial describes a multimodal protocol that includes PENG block but does not isolate its specific contribution to outcomes. 7

Insurance Coverage Considerations

• The diagnosis code G89.18 (Other acute postprocedural pain) is specifically listed as not covered for PENG block indications in clinical policy bulletins. 1
• Medical necessity cannot be established when current evidence demonstrates no significant analgesic benefit over placebo in the specific surgical population. 2

Practical Algorithm for This Case

For post-operative pain management following hip arthroscopy with labral repair:

1. Implement multimodal analgesia: Paracetamol + NSAID/COX-2 inhibitor + dexamethasone 8-10 mg IV. 3, 6
2. If regional technique desired: Use fascia iliaca block rather than PENG block. 6
3. Alternative regional option: Consider local infiltration analgesia. 6
4. Rescue analgesia: Opioids as needed for breakthrough pain. 3
5. Avoid: Femoral nerve block, lumbar plexus block, and PENG block. 3, 6, 2