Comparison between femoral block and PENG block in femoral neck fractures: A cohort study

Abstract

Background: Regional analgesia is worth performing in the multimodal postoperative management of hip fracture (HF) because it reduces hospital morbidity and mortality. The aim of this study is to compare the efficacy and side effects of the recently described "Pericapsular Nerve Group (PENG) Block" with those of the femoral block, which is considered the standard of care for postoperative pain control after femoral neck fracture.

Materials and methods: We conducted a comparative observational study at a university hospital (Saint Antoine Hospital, Sorbonne University, Paris, France), where the PENG block was introduced in August 2019. We include all patients from June to October 2019, who were coming for femoral neck fractures and who had an analgesic femoral block or PENG block before their surgery. The primary outcome was the comparison of cumulative postoperative morphine consumption 48 hours after surgery.

Results: Demographics, medical charts, and perioperative data of 42 patients were reviewed: 21 patients before (Femoral group) and 21 patients after the introduction of PENG block (PENG group) in clinical practice. Thirteen total hip arthroplasties (THA) and eight hemi arthroplasties (HA) were included in each group. Demographics were also comparable. The median, postoperative, morphine equivalent consumption at 48 hours was 10 [0-20] mg and 20 [0-50] mg in Femoral and PENG groups respectively (p = 0.458). No statistically significant differences were found in postoperative pain intensity, time to ambulation, incidence of morphine-related side effects, or length of hospital stay. The postoperative muscle strength of the quadriceps was greater in the PENG group than in the Femoral group (5/5 vs. 2/5, p = 0.001).

Conclusion: In the management of hip fractures, PENG block is not associated in our study with a significant change in postoperative morphine consumption, compared to femoral block. However, it does significantly improve the immediate mobility of the operated limb, making it appropriate for inclusion in enhanced recovery programs after surgery.

Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1. Small axis ultrasound view of the PENG block.

Using a 5 MHz abdominal probe. Images from St. Antoine Hospital, Paris.

Fig 2. PENG block realization.

Needle (★) approaching the psoas tendon. ▲ represents injection zone under the psoas tendon. AIIS: Anterior inferior iliac spine, PT: Psoas tendon, IPE: Iliopublic eminence, FA: Femoral Artery, FV: Femoral Vein.

Fig 3. Morphine consumption at different times: Before leaving the RR, 12 hours postoperatively (H12), 24 hours postoperatively (H24) and 48 hours postoperatively (H48).

Explanation of the figure: Box-plot diagram: The rectangle extends from the first quartile to the third quartile and is intersected by the median. The segments at the ends of the rectangle provide information on the extreme values.

Fig 4. Postoperative VAS score at different times: Arriving in RR, before leaving the RR, 12 hours postoperatively (H12), 24 hours postoperatively (H24) and 48 hours postoperatively (H48).

Explanation of the figure: Box-plot diagram: The rectangle extends from the first quartile to the third quartile and is intersected by the median. The segments at the ends of the rectangle provide information on the extreme values.