Charles Draznin MD and Peter Keenan MD
Chief Complaint: Right hip pain after a fall
What anatomy and pathology are shown in these Figures 1-3?
An 87-year-old man with a history of stroke with right-sided weakness presents with severe right hip pain after a fall while walking with his cane. On exam his right leg is shortened, externally rotated, and tender over the right hip. His x-ray shows an intertrochanteric hip fracture (Fig 1). Orthopedics is consulted and IV pain medication is administered but he continues to complain of pain.
Following discussion with the patient and his family members, a femoral nerve block is administered (Fig 2 and 3).
|Figure 2||Figure 3 Click Here for Video|
Within 20 minutes, the patient states his pain is significantly improved. The next day he goes to the operating room for placement of an intramedullary nail. No additional pain medication is needed from the time of the nerve block until operative fixation. He is weight bearing as tolerated following the procedure and is discharged to rehab facility on hospital day 5.
Role of Emergency Ultrasound in Pain Control
In patients with hip fractures, adequate analgesia can be difficult to obtain with oral or parenteral methods. Larger doses of narcotics carry risks of sedation, especially with elderly patients. Inadequate pain control has been shown to be associated with delirium in elderly patients.1
Regional anesthesia for pain control related to orthopedic injuries and procedures has long been practiced by anesthesiologists, but its widespread use by other fields is more recent. An increasing body of practice and literature documents its use in emergency medicine. Regional anesthesia via femoral nerve block for hip fractures has been shown to decrease patient pain and amount of parenteral narcotic analgesia required in the ED setting.2
Another option is the fascia iliaca compartment block (FICB). Rather than visualizing a nerve directly and injecting near it, this technique relies on instilling anesthetic into a compartment, and letting spread of the anesthetic provide the block. The femoral, lateral cutaneous, and obturator nerves can be blocked with the FICB. It requires a higher total volume of anesthetic than a femoral nerve block as it is a compartment block. Use of the FICB has also been described in the ED setting.3,4 Table 1 compares three local anesthetic approaches to treat hip fracture pain.
Answers to questions:
|Femoral nerve block||3 in 1 femoral nerve block||Fascia iliaca compartment block|
|Landmarks||1 cm distal to inguinal ligament, femoral nerve is lateral to femoral artery||1 cm distal to inguinal ligament, femoral nerve is lateral to femoral artery||1 cm distal to the inguinal, identify hyperechoic fascia iliaca superficial to iliacus
muscle lateral to femoral nerve (1/3 distance from ASIS to pubic tubercule)
|Volume reported||10-20 ml injected surrounding femoral nerve||25 ml injected along nerve sheath surrounding nerve||30-40ml injected just deep to fascia iliaca|
|Distribution||Anterior and medial thigh and knee, medial leg and foot, fibers to hip and knee joints||Anesthetic passes cephalad in nerve sheath to anesthetize the lateral cutaneous and obturator nerves in addition to the femoral nerve||Anesthetic passes cephalad in fascial plane to anesthetize the lateral cutaneous
and obturator nerves in addition to the femoral nerve
|Notes||May not provide reliable analgesia for hip fractures||Hold pressure 1cm below injection site for 30 seconds to 5 minutes||Femoral, lateral cutaneous, and obturator nerves run under fascia iliaca|
|Strengths||Lowest volume of anesthetic used||Lower volume of anesthetic used compared with FICB||Lower risk of intravascular injection and nerve injury since needle tip distant from vessels and nerve|
|Citations||Parker et al.||Beaudoin et al.||Haines et al.|