Regional Block

Fascia Iliaca Compartment Block (FICB)

The fascia iliaca compartment block delivers local anaesthetic into the fascia iliaca compartment — a potential space beneath the fascia iliaca that contains the femoral nerve, lateral femoral cutaneous nerve (LFCN), and obturator nerve. The fascia iliaca is a thick fascial layer covering the iliacus and psoas muscles. The femoral nerve (L2–L4) lies lateral to the femoral vessels beneath the fascia iliaca and inguinal ligament. The LFCN (L2–L3) typically exits medial to the anterior superior iliac spine (ASIS). The obturator nerve runs deeper in the pelvis.

Onset15–30 minutes for full block

Duration12–18 hours with levobupivacaine 0.25%

CoverageFemoral nerve: anterior thigh and medial lower leg (saphenous nerve)

Clinical Note

NICE NG111: All patients with hip fracture should be offered FICB as early analgesia. Document block time, drug, dose, operator. For elderly patients on anticoagulants, the benefit of pain relief (reducing delirium, facilitating examination) generally outweighs the small haematoma risk.

Indications

Proximal femur fracture (neck of femur, intertrochanteric fracture) — first-line EM analgesia
Femoral shaft fracture
Hip dislocation
Knee surgery / femoral condyle fractures
Skin grafting from anterior thigh
Femoral arterial line/catheter insertion analgesia
Painful quadriceps haematoma
Burns to anterior thigh
Hip arthroplasty (post-operative analgesia)
NICE guideline NG111 recommends fascia iliaca block for proximal femur fractures in the ED

Contraindications

Patient refusal
Infection at injection site (inguinal cellulitis, abscess)
Significant coagulopathy — relative contraindication; risk vs benefit in NOF fracture (RCEM guidance: do not withhold for anticoagulant use alone if clinically indicated)
Known allergy to local anaesthetic
Previous femoral vascular surgery (distorted anatomy)
Lymphoedema (increased infection risk)
Inability to cooperate

Technique

Patient supine; expose inguinal region
LANDMARK METHOD (if ultrasound unavailable): palpate ASIS and pubic tubercle; divide inguinal ligament into thirds; injection point at junction of medial and lateral thirds; 2-click technique (fascia lata then fascia iliaca)
ULTRASOUND METHOD (preferred): Linear probe placed infrainguinal, parallel to inguinal ligament, lateral to femoral artery
Identify fascia iliaca (bright hyperechoic layer) overlying iliopsoas muscle
In-plane needle from lateral to medial; target plane deep to fascia iliaca and superficial to iliopsoas
Hydrodissect with 1–2 mL saline; confirm spread lifting fascia iliaca off iliopsoas
Inject 30–40 mL local anaesthetic slowly with aspiration every 5 mL
For superior FICB (Hebbard approach): probe placed more superiorly, medial to ASIS — higher obturator nerve block rate

Drug Doses

Agent	Concentration	Volume	Total Dose	Notes
Levobupivacaine	0.25%	30–40 mL	75–100 mg	Recommended by RCEM/BPS. Long duration 12–18h. Max dose 2 mg/kg. Most commonly used in UK EDs.
Ropivacaine	0.375%	30–40 mL	112–150 mg	Good safety profile. Max 3 mg/kg. Comparable efficacy to levobupivacaine.
Bupivacaine	0.25%	30–40 mL	75–100 mg	Max 2 mg/kg; do not exceed 150 mg. Higher cardiotoxicity risk than levobupivacaine — avoid in cardiac disease.
PAEDIATRIC (>5 years)	Levobupivacaine 0.25% or Ropivacaine 0.2%	0.5–1 mL/kg (max 30 mL)	≤2 mg/kg levobupivacaine; ≤3 mg/kg ropivacaine	Weight-based dosing essential in children. Lower concentrations reduce toxicity risk.

Onset

15–30 minutes for full block; initial analgesia within 10 minutes

Duration

12–18 hours with levobupivacaine 0.25%; 8–12 hours with ropivacaine

Complications

LAST (Local Anaesthetic Systemic Toxicity)

Highly vascular inguinal region. Large volumes used (30–40 mL). Use maximum doses with weight-based calculation. Aspirate every 5 mL. Femoral vessels in close proximity.

Femoral Nerve Palsy

Temporary quadriceps weakness expected as part of block effect. Persistent weakness or neurotoxicity from intraneural injection is rare but possible. Never inject against resistance.

Femoral Vessel Injury/Haematoma

Inadvertent arterial or venous puncture — apply compression. Ultrasound guidance significantly reduces this risk.

Block Failure

Landmark technique: ~30% failure rate. Ultrasound-guided: ~5–10% failure. Most common cause is injection superficial to fascia iliaca or medial to femoral nerve.

Peritoneal Puncture

Very rare with correct technique. Excessive needle depth directed superiorly can penetrate peritoneum or iliac vessels.

Infection

Rare with aseptic technique. Risk increased in contaminated wounds or immunocompromised patients.

Landmarks

Anterior superior iliac spine (ASIS)
Pubic tubercle (medial landmark)
Inguinal ligament (line between ASIS and pubic tubercle)
Femoral artery (medial to femoral nerve — to be avoided)
Femoral nerve (lateral to artery, beneath fascia iliaca and fascia lata)
Iliopsoas muscle (target muscle belly beneath fascia iliaca)

Sensory Coverage

Femoral nerve: anterior thigh and medial lower leg (saphenous nerve). Lateral femoral cutaneous nerve: lateral thigh (variable). Obturator nerve: medial thigh (variable — more reliable with superior approach). Does NOT cover posterior thigh (sciatic nerve territory).

Clinical Pearls

NICE guideline NG111 recommends offering FICB as soon as possible, ideally within 60 min of presentation

Do not withhold block solely because of anticoagulant use in NOF fracture — assess risk vs benefit

Superior (infra-inguinal lateral) approach gives better obturator nerve coverage for hip surgery

For landmark technique: 2-click method (fascia lata then fascia iliaca) is a useful teaching aid

Ensure patients can mobilise safely — assess quadriceps strength before mobilising (fall risk)

Document block, drug, dose, volume, time, and consent in notes

Background & Evidence

The fascia iliaca block is the most widely used regional technique in UK emergency departments, primarily for proximal femur fractures. NICE guidance (NG111, 2017) recommends it within 60 minutes of ED arrival. Studies show it reduces opioid requirements, delirium rates, and time to first mobilisation. The RCEM clinical standards recommend all EDs performing hip fracture care should have competent practitioners available to perform FICB. The superior approach (Hebbard technique) has demonstrated more reliable obturator nerve blockade in cadaveric and clinical studies.

Ultrasound Images

Fascia iliaca compartment block: probe positioning, landmarks (ASIS, inguinal ligament), and ultrasound showing fascia iliaca, internal oblique, sartorius, and ilium — Probe placement relative to ASIS and inguinal ligament (top left), and ultrasound images showing the fascia iliaca layer, needle path, and local anaesthetic spread (asterisks)

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