The Indian Anaesthetists’ Forum

: 2021  |  Volume : 22  |  Issue : 1  |  Page : 60--66

Role of ultrasound-guided lumbar “Erector spinae plane block” and ultrasound-guided transmuscular “Quadratus lumborum block” for postoperative analgesia after hip surgeries: A randomized, controlled study

Prashant Tiwari, Rohan Bhatia, Veena Asthana, Rajesh Maheshwari 
 Department of Anaesthesiology, HIMS, Dehradun, Uttarakhand, India

Correspondence Address:
Dr. Rohan Bhatia
Department of Anaesthesiology, HIMS, Dehradun, Uttarakhand


Background and Aims: Our aim was to assess the postoperative analgesia after ultrasound-guided transmuscular “Quadratus lumborum block” (QLB) and lumbar “Erector spinae plane block” (ESPB) in hip surgeries postoperatively. Design: Double-blinded, randomized prospective study. Materials and Methods: Sixty-three patients who underwent hip surgeries were divided into three groups, with 21 patients each. Each group was given spinal anesthesia using 30 ml of 0.5% hyperbaric bupivacaine. After the completion of the surgery, Group I patients were given ipsilateral transmuscular QLB and Group II patients were given ipsilateral lumbar ESPB. No block was given in Group III. In the postanesthesia care unit (PACU), pain was assessed using the Numeric Rating Scale (NRS) scoring. The time of first analgesic requirement and the total postoperatively tramadol consumption in first 24 h was recorded. Results: No significant difference was seen between the three groups pertaining to patient's demographic data, type, and duration of surgery. Statistically significant lower NRS scores were present in QLB group and ESPB group than the control group in the first 24 h (P < 0.001). The total tramadol consumption was significantly more in the control group (346.67 ± 71.37) mg than QLB group (159.05 ± 39.74) mg and ESPB group (190.48 ± 33.83) mg with P < 0.001. Time duration of first analgesic requirement in PACU was 344.05 min, 267.86 min, and 105.24 min for QLB, ESPB, and control group, respectively. Conclusion: In conclusion, both QLB and ESPB provide good postoperative pain control in hip surgeries with QLB providing a better analgesic profile when compared to ESPB.

How to cite this article:
Tiwari P, Bhatia R, Asthana V, Maheshwari R. Role of ultrasound-guided lumbar “Erector spinae plane block” and ultrasound-guided transmuscular “Quadratus lumborum block” for postoperative analgesia after hip surgeries: A randomized, controlled study.Indian Anaesth Forum 2021;22:60-66

How to cite this URL:
Tiwari P, Bhatia R, Asthana V, Maheshwari R. Role of ultrasound-guided lumbar “Erector spinae plane block” and ultrasound-guided transmuscular “Quadratus lumborum block” for postoperative analgesia after hip surgeries: A randomized, controlled study. Indian Anaesth Forum [serial online] 2021 [cited 2021 Jun 20 ];22:60-66
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Full Text


Utilization of ultrasound has led to increase in the number of newly described musculofascial plane blocks because of real-time visualization of nerves, needle, and other anatomical structures.[1],[2]

Quadratus lumborum block (QLB) was first described by Blanco in 2007 as an interfascial block of posterior abdominal wall which is done only under US guidance. It blocks T7-L1 nerve fibres in most of the cases. There are four types of QLB described. Quadratus lumborum 3(QL3) block (Transmuscular QLB) in which local anesthetic (LA) is given anterior to the QL muscle, i.e., between the QL muscle and the psoas major muscle. Studies have reported its use in the management of postoperative pain after hip surgeries.[3]

“Erector Spinae Plane Block” (ESPB) is another such block, first used for thoracic neuropathic pain by Forero et al.[4] It rose in popularity for the management of postoperative pain for breast surgery,[5],[6] thoracic surgery,[7] chronic shoulder pain[8] as well as upper abdominal surgeries.[9] It is also an US-guided interfascial plane block. In ESPB anesthetic drug is injected between the anterior surface of erector spinae muscle and transverse process of underlying vertebra. There are some case reports in which ESPB is performed at the lumbar level.[10] It has been seen that ESPB when given at the lumbar region gives blockade from C7-T2 to L2–L3.[10]

In the past 2–3 decades, the utilization of hip arthroplasty has increased, in the management of refractory hip pain. Acute postoperative pain after hip surgeries can range from moderate to severe and also acute postoperative pain in the later stage can lead to chronic hip pain after joint replacement.[11] Evidences reinstate multimodal analgesia as a better approach for postoperative pain. It decreases opioid requirement and at the same time reduces opioid-related side effects.[12] Peripheral nerve blocks alone or when given as a part of multimodal analgesia are one of the safest and most effective methods for postoperative pain control. It causes decreased length of hospital stay, faster recovery, and prevents readmissions.[13]

In this study, our aim was to assess the postoperative analgesia after ultrasound-guided transmuscular QLB and lumbar ESPB in hip surgeries postoperatively.

 Materials and Methods

This randomized controlled, prospective, double-blinded, study was performed in a tertiary care health center for a period of 12 months after institutional ethics committee approval. Informed consent in written was taken from the patient's listed undergoing elective hip surgery. Sixty-eight patients of either sex, 20–70 years of age, “American Society of Anesthesiology” (ASA) Grades 1 and 2 were recruited in the study.

Patient refusing for regional anesthesia, allergy to local anesthetics, bleeding disorders, local site infection, patient on anti-coagulants, inability to give informed consent, severe liver and kidney disease, patients with inability to operate patient controlled analgesia (PCA) system, and psychiatric disorders were excluded from the study. Out of 68 patients, 5 patients were excluded from the study [Figure 1].{Figure 1}

Eligible patients were kept fasting for 6 h for solid food and 2 h for clear fluid before the surgery. Patients were given tablet ranitidine 150 mg and tablet alprazolam 0.25 mg at bed time and 2 h before surgery as a premedication.

In the preoperative room, all the patients were explained about the anesthetic procedure and the interpretation of Numeric Rating Scale (NRS). In the operating room after establishing intravenous access, standard monitoring such as noninvasive blood pressure (BP), electrocardiogram, and oxygen saturation (SpO2) was recorded.

The patients were assigned to receive either QLB or ESPB or no block (control group). Twenty-one patients were allocated to each group. After enrolment, group assignments were determined by a computer-generated number sequence and were contained in sequentially numbered opaque envelopes to ensure blinding. The participants (patients) and the data collector (nurse) were kept blinded from the intervention done. A CONSORT flow diagram for this study is shown in [Figure 1].

The anesthetic technique for all patients was spinal anesthesia. Spinal anesthesia was given in the sitting position at L3-4 or L4-5 inter-vertebral level in the median approach with 27-G spinal needle and 3 ml of 0.5% bupivacaine (hyperbaric) was injected intrathecally. The patient was then positioned supine immediately. After adequate anesthesia effect, surgical procedure was started. Ultrasound-guided QLB or ESPB were performed after the completion of surgery and were performed by trained anesthesiologist with experience in ultrasound imaging for nerve blocks for >1 year. Ultrasound machine used was (M TURBO. FUJIFILM Sonosite, Inc., 21919 Bothell, WA 98021 USA). US probe used was Curvilinear 2-5 MHz.

QL3 block was performed in the lateral position in one group of patients. The convex transducer of ultrasound machine was placed on the flank of the patient in transverse plane cranial to iliac crest. Then, 4th lumbar vertebral transverse process, transverse abdominis muscle, psoas major muscle, quadrates lumborum muscle, and internal and external oblique were identified. A 10 cm 20G (Stimuplex Ultra 360) needle was introduced from the posterior corner of curvilinear probe (in plane technique). Thirty milliliter 0.2% of ropivacaine local anesthetic was administered into the fascial plane between the quadratus lumborum and psoas major muscle. Under ultrasound visualization, the local anesthetic was observed pressing upon the psoas muscle.

In another group of patients, lumbar ESP block was performed in the lateral position. A convex ultrasound transducer was placed 4–6 cm lateral to L4 spinous process in a longitudinal parasagittal orientation. The erector spinae muscle was identified superficial to the “transverse process” of L4 vertebra. Using an in-plane superior-to-inferior approach, a needle of 10-cm 20-G (Stimuplex Ultra 360) was advanced with tip introduced up to the plane anterior to the “erector spinae muscle” and posterior surface of transverse process. The tip of needle was localized by the spread of injected saline which hydrodissected the erector spinae muscle from the transverse process of L4. 30 ml of ropivacaine 0.2% was injected. No block was given in the third group of patients at the end of the surgery.

Patients were transferred to the postanesthesia care unit (PACU). Monitoring and recording of standard parameters such as BP (systolic/diastolic/mean), heart rate, and SpO2 were done. The intensity of pain was assessed by using the NRS scoring system from 20 min after the block followed by assessment at 1, 3, 6, 12, 18, and 24 h. Tramadol PCA pump was used to supplement analgesia so that patient can themselves administer tramadol, if required. The demand dose of tramadol through PCA pump was 20 mg with lockout interval of 10 min. However, if pain persisted even after the administration of tramadol, 1 g intravenous paracetamol was used as a rescue analgesic. The time duration of the first analgesic demanded by the patient and the total amount of tramadol consumed after 24 h of surgery were recorded.

In statistical analysis, the primary outcome was NRS score. NRS is a 10-point scale with 10 denotes “worst pain imaginable” and 0 indicates “no pain.” Higher the scores, worse are the outcomes.

The secondary outcome variables were:

Total opioid consumption over 24 hTime of first analgesic used over 24 h (time from the block administration to first analgesic demand by the patient)Any opioid-related side effects during first 24 hLikert-scale questionnaire on the postoperative day (POD) 1 was done to know the patient's satisfaction.

Statistical analysis

The Statistical Package for the Social Sciences System version contractor/manufacturer is SPSS Inc., 233 south wacker drive, 11th Floor, Chicago, IL 60606-6412. Patent No. 7,023,453 was used for statistical testing. For unevenly distributed data, mean ± standard deviation or median was used to denote the continuous variables. Percentages and frequencies represented categorical variables. Continuous variables are compared between the groups using the Student's t-test. Chi-square test or Fisher's exact test were used to compare the nominal categorical data between the groups. The Mann–Whitney U-test was used to compare the nonnormal distribution variables. For all statistical tests, a P < 0.05 is taken to indicate a significant difference.


A total of 68 patients fulfilling the eligibility criteria were included in the study, of which 63 completed the study. Four patients in this study were excluded because the effect of spinal anesthesia had weaned off before the block administration. A Marijuana abuser was excluded from the study to avoid the interference of excessive Tramadol consumption inconsistent with the pain scores of the patient.

Patient's demographics, ASA grading, type of the surgeries, subarachnoid block duration, and duration of surgery were statistically similar [Table 1].{Table 1}

Patients in each group were assessed for pain using NRS score at different time intervals in 24 h. Patients in the QLB group and ESPB group had lower pain scores as compared to control group at 1, 3, 6, 9, 12, 18, and 24 h (P < 0.001). When NRS scores between QLB and ESPB were compared at 1, 3, 6, 9, 12, 18, and 24 h, no statistically significant difference was seen (P > 0.001) [Figure 2] and [Table 2].{Figure 2}{Table 2}

Mean of total tramadol consumption over 24 h was 159.05 ± 39.74 mg in Group I (QLB), 190.48 ± 33.83 mg in Group II (ESPB) and 346.67 ± 71.37 in Group III (controls) which was statistically significant (P < 0.001). No statistically significant difference was found between QLB group and ESPB group when compared for total tramadol consumption (P = 0.122). Total tramadol consumed was comparatively more in the control group when compared with Group I (QLB) (P < 0.001) and when compared with Group II (ESPB) (P < 0.001) [Figure 3] and [Table 3].{Figure 3}{Table 3}

The average time of first analgesic used/requested after the patient was received in PACU was recorded. Statistically significant difference was seen among the three groups. Time of first analgesic used was 344.05 ± 91.80 min in QLB group, 267.86 ± 56.82 min in ESPB group, and 105.24 ± 50.39 min in the control group, with the duration being the longest in QLB group followed by ESPB and least in the control group [Table 4].{Table 4}

No statistically significant difference was found for opioid-related side effects among the three groups (P = 0.070).

Patient's satisfaction was assessed next day after 24 h of the study using the Likert scale. Overall pain management was good in QLB group and ESPB group than the control group (P < 0.001) [Table 5]. The quality of sleep last night (POD 0) was also asked to the patients. Patients in both the block groups had better sleep experience than the control group.{Table 5}


In this study, we found that both the transmuscular QLB and lumbar ESPB have statistically significant postoperative pain control than the control group. Opioid consumption and NRS pain scores after the first 24 h of surgery were significantly lower in blocks group than the control group. Both the block groups were statistically comparable in terms of postoperative pain control and patient's satisfaction. However, in QLB group, time duration of the first analgesic requirement in PACU is significantly more as compared to the ESPB group and control group.

Nerve supply of hip joint comes from lumbar plexus (L2–L4) along with a part of the sacral plexus (L4-S1). The skin innervation in hip arthroplasty (posterolateral approach) is from the “lateral cutaneous branch of iliohypogastric nerve” (T12 and L1), “subcostal nerve” (T12), and “lateral femoral cutaneous nerve” (L2–L3).[14],[15] Conventionally, epidural analgesia is the analgesic modality of choice in hip arthroplasty.[16] In the recent past, the number of truncal blocks such as “QLB,” “Transverse abdominis plane (TAP) block,”, “lumbar plexus block,” “paravertebral block,” and “ESPB” have been successfully used in hip surgeries.[17]

QLB as a modification of TAP block was first delineated by Dr Rafael Blanco.[18] In Anterior QLB, also known as transmuscular QLB, the drug spreads posteriorly into the lumbar paravertebral space.[19] In a study based on a cadaveric model with anterior QLB at L4 and L2, conducted by Dam et al. demonstrated spread of dye into the thoracic paravertebral space upto T9-10 level.[20] A plausible mechanism of action suggested by the study was that the dye spread directly into the lumbar plexus. Involvement of L1–L3 nerve roots was consistently observed in anterior QLB at L3–L4 level cadaveric study.[21] A study done by Akerman et al. explained the role of “Thoracolumbar fascia” (TLF) in the analgesia provided by QLB. TLF contains low- or high-sensitive pain receptors and mechanoreceptor which are blocked by LAs in QLB, thus may provide additional analgesia unlike other truncal blocks.[3] This may be reason why QLB has greater “time of first analgesic requirement” than ESPB group in our study. However, there has been no study till date which evaluates the time of first analgesic requirement after the truncal blocks in hip surgery. There are multiple studies demonstrating significant outcomes and better postoperative pain control in hip surgeries where QLB is given.[22],[23],[24],[25],[26],[27],[28] Furthermore, there is a low risk of LAST associated with QLB; hence, increasing its safety profile. Pharmacokinetic studies based on ropivacaine usage showed the plasma concentration to be within threshold levels after QLB administration.[29]

ESPB was initially used for thoracic,[7] shoulder,[8] breast,[5],[6] and upper abdominal surgeries.[9] The deposition of the LA is within the confines of the erector sheath compartment, in ESPB. The success of the block is dependent on the distribution of LA agent not just cranially and caudally through the erector sheath but also by subsequent infiltration into the paravertebral space through the anterior sheath apertures.[30] The observation by Hamilton and Manickam was suggestive of the possibility that the optimal plane of the injection might be within the investing sheath instead of being deeper to it.[30] Recently, a study utilized “magnetic resonance imaging” to show that the mechanism of ESPB is due to the spread into the epidural and transforaminal space, which may provide an edge over the other interfascial plane blocks of the thorax such as serratus anterior, TAP and pectoralis nerve block in view of the fact that unlike others, abdominal visceral analgesia is also provided by ESP Block.[31] Chin et al. proposed that instead of relying on the LA spread adequacy, an ESPB should be administered at the vertebral level corresponding to the abdominal incision.[32] ESPB is also described at the lumbar level. Several anatomical, sonographic, and application-based differences were described by Kose et al. between ESPB at the lumbar and thoracic level.[33] The rigid boundaries of thoracic paravertebral space contribute to multilevel analgesia by ensuring the diffusion of even small LA volumes in thoracic ESPB, to affect the ventral and dorsal rami at several levels. However, such delineated boundaries are not present in the lumbar paravertebral spaces. Therefore, the anterior spread of LA in lumbar paravertebral space is only partial. The increased erector spinae muscle thickness increases the complexity of lumbar ESP block.[34] Keeping this in mind, ESP was administered at a lower thoracic level by Darling et al., and the catheter was directed caudally. Lumbar ESP block as a constituent of multimodal analgesia has also been elucidated after lumbar spine surgeries. The results of ESPB at L4 level in total hip arthroplasty were comparable to those with epidural analgesia in a study by Tulgar and Senturk.[35]

At present, there are no randomized control trial studies to assess the ESP block efficacy at different concentration levels of LA. Some recommendations suggest using larger volumes for more dermatomal coverage and improved paravertebral space diffusion. Lower LA volume usage causes an inadequate spread of LA when performed at the thoracic level. A better postoperative pain management was observed on using a higher bupivacaine concentration (0.37%) 20 ml as opposed to using 0.25% bupivacaine (20 ml) in the study conducted by Altıparmak et al.[36]

However, our study did not include the dynamic pain scores as the hip joint is usually kept immobile by the surgeon on 1st POD. Patients where the effect of spinal anesthesia weaned off before the block administration were also excluded from our study. The assessment of the motor power of the lower limb muscles was not taken into consideration. 30 ml of ropivacaine 0.2% was used in this study. There is the possibility of better analgesic effects if higher concentrations are used. Furthermore, the role of mechanoreceptors in prolonging the duration of analgesia by QLB as seen in our study needs to be further evaluated. In this study, we did not assess long-term pain and duration of hospital stay. Complications such as itching, nausea, and vomiting were not found in our study.


We would like to conclude that both transmuscular QLB and ESPB provide good postoperative pain control in hip surgeries with QLB providing a better analgesic profile when compared to ESPB.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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