Lumbar Plexus Block/Psoas Compartment Block

The LPB has the definitive advantage of providing profound coverage of T12 to L4 for hip surgery. It was first described by Winnie and colleagues in 1974 as LPB, then as PCB in 1976 by Chayen and colleagues. Many more modifications have been proposed over the years. Although anesthesiologists have not been able to agree on the exact anatomic space that is being targeted, thus proposing various names for the nerve block, the fundamental goal is to block the lumbar plexus. Hereupon, all similar nerve blocks will be referred to as LPB in this section. No differences exist in clinical efficacy among the different approaches, but side effects tend to be fewer with nerve blocks performed at the L4 level and with a more lateral approach.

The first study on the efficacy of LPB in hip surgery was published in 2000 by Stevens and colleagues, who recruited 60 patients into their study. They concluded that the LPB group had greater analgesia, especially during the first 6 hours postoperatively. Their study also showed that LPB modestly decreased perioperative blood loss up to 48 hours postoperatively. A similar result was reported by Biboulet and colleagues : single-shot LPB was effective for purposes of analgesia for up to 4 hours, and no difference was seen in functional outcomes.

Several research studies on continuous LPB further supported its efficacy in hip surgery. Continuous LPB reduces narcotic consumption and related side effects and improves patient satisfaction. It seems that continuous LPB is not inferior to FNB, and LPB is equally effective for postoperative analgesia compared with continuous epidural analgesia. Omar and colleagues compared single-shot LPB with single-shot caudal block in pediatric patients undergoing hip surgery and found that single-shot LPB was superior to caudal block in the duration of analgesia postoperatively. Even though all evidence indicated that LPB was effective in analgesia for hip surgery, continuous LPB failed to show long-term outcome benefits 12 months after hip arthroplasty.

Femoral Nerve Block/Fascia Iliaca Block/3-in-1 Nerve Block

FNB alone is not sufficient for hip surgery simply because it does not provide sufficient coverage for the obturator nerve, lateral femoral cutaneous nerve, and sciatic nerve distribution. Detailed review of all articles on nerve blocks of the femoral nerve for hip surgery showed that all studies were intended to block the femoral nerve, obturator nerve, and lateral femoral cutaneous nerve. Although the names of the nerve blocks were reported differently, all intentions were to inject under the fascia iliaca or to diffuse local anesthetic retrograde within the femoral nerve sheath to target the lumbar plexus.

Goitia Arrola and colleagues reported that single-injection FIB was initially effective in controlling postoperative pain after total hip replacement; however, the effect was short-lived. Uhrbrand and colleagues concluded that 3NB injection was also beneficial for postoperative analgesia but that this result might not be clinically relevant because of its limited benefit. Beaudoin and colleagues studied ultrasound-guided FNB in the emergency department in elderly patients with hip fractures. The authors concluded that injection under the fascia iliaca with intentional cephalic spreading significantly reduced pain over their observation period. A similar conclusion was drawn by Stevens and colleagues, who also noted a narcotic sparing effect up to 24 hours postoperatively.

Winnie and colleagues first described 3NB as the anterior approach to the LPB. They specifically highlighted the importance of targeting the three main branches of the lower extremity, femoral nerve, obturator nerve, and lateral femoral cutaneous nerve. Ilfeld and colleagues compared a continuous FNB with a posterior LPB in postoperative analgesia after total hip arthroplasty and concluded that both approaches were equally effective. The continuous catheter was placed with continuous nerve stimulation, thus making the approach similar to an anterior approach with LPB.

Singelyn and Gouverneur compared intravenous patient-controlled analgesia (IV PCA), epidural analgesia, and continuous 3NB. Although all approaches were effective in controlling postoperative pain, the authors noted significantly less side effects, such as nausea, vomiting, and pruritis, in the 3NB group. Although these studies confirm that regional analgesia can provide a certain level of benefit for patient care, Biboulet and colleagues found IV PCA to be safe and effective after comparing IV PCA, FNB, and PCB.

FNB/3NB is easy to perform and has showed promising analgesic effects, but the evidence is less convincing. For hip surgery, dermatome coverage may be quite challenging because it involves both the lumbar plexus and sacral plexus. One interesting article published by de Leeuw and colleagues illustrated the concept of using high-volume expansion to cover both the lumbar plexus and the sciatic nerve with one injection technique. This technique covers L2-S2 but may not cover L1, which was a common site of pain among patients in the study. The authors’ results were very encouraging. However, the concentration and amount of local anesthetic used might be unacceptable to some anesthesiologists. Currently, ongoing clinical trials are investigating the application of FIB in hip surgery.

Local Infiltration Analgesia

LIA for hip surgery was first reported by Bianconi and colleagues in 2003. The concept is very appealing because of its simplicity and safety. It has gained popularity over the last several years mostly among orthopedic surgeons. The local anesthetic mixture contains various medications and concentrations based on institutional or departmental protocol. In general, it contains local anesthetics, epinephrine, narcotics, ketorolac, antibiotics, and steroids.

Several studies have supported the effectiveness of LIA. However, most of these studies have limitations. Andersen and colleagues reported that LIA was effective in controlling postoperative pain; however, their study was poorly designed and lacked control subjects. Andersen and colleagues reported that LIA was effective in decreasing pain and opioid consumption postoperatively; however, no nonsteroidal antiinflammatory drugs (NSAIDs) were given to the control group. Three other studies support the efficacy of LIA in hip surgery patients, but all have similar study design limitations. Scott and colleagues reported that periarticular injection of local anesthetics decreases perioperative narcotic consumption and length of hospitalization. However, the study was a retrospective, nonrandomized, controlled chart review.

The validity of LIA was finally addressed in 2011 with two double-blind randomized controlled studies. Both studies concluded that there were no difference between intraoperative LIA and saline. It is important to note that both studies adopted multimodal pain management algorithms as the basis for perioperative pain management. However, an interesting article from Switzerland in 2012 suggested that continuous epicapsular LIA was effective in decreasing morphine consumption and in improving postoperative analgesia.

More studies are required to determine whether LIA is effective for hip surgery, but it seems that LIA is an acceptable alternative approach for postoperative pain control. However, its merit is limited by coexisting multimodal postoperative pain management algorithms, especially when NSAIDs are added to the algorithm.

Intravenous Patient-Controlled Analgesia and Epidural Analgesia

Both PCA and epidural analgesia have been widely used clinically for analgesia management. Both approaches can provide analgesia for hip surgery, but both have distinct advantages and disadvantages. IV PCA is easy to set up and is effective in general. However, the opioid does not reliably provide sufficient analgesia, and the dosage is difficult to predict, especially among patients who are already dependent on narcotics because of long-term use, which is a fairly common situation among patients undergoing total hip replacement. In addition, opioids can cause excessive sedation, respiratory depression, nausea and vomiting, constipation, and pruritis.

Epidural analgesia is a very reliable technique that provides superior pain relief after total hip replacement. However, it is associated with certain risks, such as spinal hematoma, transient neurologic symptoms, and caudal equina syndrome. The risks may be further increased if clinical use of anticoagulation therapy becomes more prevalent. In addition, epidural analgesia is also associated with more hypotension, urinary retention, and motor block. These side effects could impair the physical therapy and rehabilitation process.