PENG Block Nerve Targets
The PENG (Pericapsular Nerve Group) block targets the sensory branches of the femoral nerve, obturator nerve, and accessory obturator nerve (when present) that innervate the anterior hip joint capsule. 1
Specific Anatomical Targets
The block is designed to anesthetize three distinct nerve structures:
- Femoral nerve sensory branches provide the primary innervation to the anterior hip capsule 1
- Obturator nerve sensory branches contribute to hip joint capsule sensation 1
- Accessory obturator nerve (present in approximately 10-30% of patients) supplies additional anterior capsule innervation when anatomically present 1
Key Clinical Characteristics
The PENG block is specifically designed as a motor-sparing technique that preserves quadriceps function while providing targeted hip analgesia, distinguishing it from traditional femoral nerve blocks that cause significant motor weakness 1. This motor-sparing property has been validated in over 50 publications by 2021 1.
Coverage Area
The block provides anesthesia limited to:
- The shoulder and upper third of the humerus (when applied to shoulder surgery) 2
- The anterior hip capsule without causing muscle laxity or motor blockade 2
Clinical Pitfalls
A critical caveat: the PENG block alone is not sufficient for complete surgical anesthesia 2. While it provides excellent analgesia for hip procedures like total hip arthroplasty, it should be considered part of a multimodal analgesic approach rather than a standalone anesthetic technique 2. The block demonstrates significant reductions in opioid consumption (mean reduction of 3.75 mg MME at 24 hours) 3 and allows for earlier mobilization 4, but requires supplementation with other analgesic modalities for complete surgical coverage.