Prevalence of chronic pain syndrome in patients who have undergone hallux valgus percutaneous surgery: a comparison of sciatic-femoral and ankle regional ultrasound-guided nerve blocks

Abstract

Background: Chronic pain syndrome (CPS) is a common complication after operative procedures, and only a few studies have focused on the evaluation of CPS in foot-forefoot surgery and specifically on HV percutaneous correction. The objective of this study was to compare postoperative pain levels and incidence of CPS in two groups of patients having undergone femoral-sciatic nerve block or ankle block regional anaesthesia before hallux valgus (HV) percutaneous surgery and the association between postoperative pain levels and risk factors between these patient groups.

Methods: A consecutive patient series was enrolled and evaluated prospectively at 7 days, 1, 3 and 6 months after surgery. The participants were divided into two groups according to the regional anaesthesia received, femoral-sciatic nerve block or ankle block, and their outcomes were compared. The parameters assessed were postoperative pain at rest and during movement by the numerical rating scale (NRS), patient satisfaction using the Visual Analogue Scale (VAS), quality of life and return to daily activities. Statistical analysis was performed.

Results: One hundred fifty-five patients were assessed, 127 females and 28 males. Pain at rest (p < 0.0001) and during movement (p < 0.0001) significantly decreased during the follow-ups; at 6 months, 13 patients suffered from CPS. Over time, satisfaction remained stable (p > 0.05), quality of life significantly increased and patients returned to daily activities and work (p < 0.0001). No significant impact of type of anaesthesia could be detected. ASA 3 (p = 0.043) was associated to higher pain during movement; BMI (p = 0.005) and lumbago (p = 0.004) to lower satisfaction. No operative-anaesthetic complications were recorded. Postoperative pain at rest and during movement improved over time independently of the regional block used, with low incidence of CPS at last follow-up. Among risk factors, only a higher ASA was associated to higher pain during movement, while higher BMI and lumbago to lower satisfaction.

Conclusions: Both ultrasound-guided sciatic-femoral and ankle blocks were safe and effective in reducing postoperative pain with low incidence of CPS at last follow-up.

Trial registration: Clinical Trial NCT02886221 . Registered 1 September 2016.

Keywords: Anaesthesia; Ankle block; Chronic pain; Femoral-sciatic block; Foot surgery; Hallux valgus; Minimally invasive surgery; Postoperative pain.

Conflict of interest statement

The corresponding author, Carlo Biz, is a member of the Editorial Board of BMC Musculoskeletal Disorders. The remaining authors declare that they have no conflict of interests related to the publication of this manuscript, and they have not received benefits or financial funds in support of this study.

© 2021. The Author(s).

Figures

Fig. 1

Ultrasound (A-C) and clinical (B-D) images of femoral-sciatic nerve block procedures with the patient lying in a supine position. For femoral block (A-B), using an ultrasound-guided technique (A), the needle is advanced through the fascia lata and iliaca until an adequate position with respect to the femoral nerve (FN) is reached. The site of needle insertion (B) is located at the femoral crease but below the inguinal crease and immediately lateral to the pulse of the femoral artery (FA). For sciatic block (C-D), using an ultrasound-guided technique (C), the sciatic nerve (SCN) is seen as a hyperechoic oval structure sandwiched between the adductor magnus muscle and the hamstring muscles. The nerve is typically visualised at a depth of 6–8 cm, under the femoral artery (FA), the femur and the adductor magnus muscle. The needle is inserted in plane from the medial aspect of the thigh and advanced toward the sciatic nerve (D)

Fig. 2

Anatomical dissection image of the anterolateral aspect of the lower leg and ankle demonstrating the anatomy of the nerves of the lateral compartment of the ankle involved in the ankle blocks: (1) the sural nerve and (2) the superficial peroneal nerve. The dissection shows the distal division of the sural nerve into several branches along the lateral aspect of the ankle and foot and the two branches of the superficial peroneal nerve (the medial and intermediate dorsal cutaneous nerves)

Fig. 3

Anatomical dissection image (A) of the region of the tarsal tunnel demonstrating the anatomy of the nerves of the medial compartment of the ankle involved in the ankle blocks: the tibial nerve: (1) Medial calcaneal branches; (2) Medial plantar nerve; (3) Lateral plantar nerve; (4) Inferior calcaneal nerve (Baxter’s nerve). On the right, detail (B) of the first metatarsophalangeal joint showing the percutaneous entry points for (5) the first metatarsal distal osteotomy (Reverdin-Isham) and for (6) the first phalanx osteotomy (Akin)

Fig. 4

Anatomical, ultrasound and clinical images of ankle block procedures, which involve anaesthetising five separate nerves: two deep (posterior tibial and deep peroneal) and three superficial nerves (superficial peroneal, sural and saphenous). (1) Deep Peroneal Nerve: it innervates the ankle extensor muscles, the ankle joint and the web space between the first and second toes. A transducer placed in the transverse orientation at the level of the extensor retinaculum will show this nerve (DPN) lying immediately lateral to the anterior tibial artery (ATA) on the surface of the tibia. (2) Superficial Peroneal Nerve: it innervates the dorsum of the foot and emerges to lie superficial to the fascia, 10–20 cm above the ankle joint on the anterolateral surface of the leg, and divides into two or three small branches. A transducer placed transversely on the leg, approximately 5–10 cm proximal and anterior to the lateral malleolus, will identify the hyperechoic nerve branches (SPN) lying in the subcutaneous tissue immediately superficial to the fascia. (3) Sural Nerve: it innervates the lateral margin of the foot and ankle. This nerve (SUN) can be traced back along the posterior aspect of the leg, running in the midline superficial to the Achilles tendon and gastrocnemius muscles, in the immediate vicinity of the small saphenous vein (V). (4) Posterior tibial nerve: it provides innervation to the heel and sole of the foot. This nerve (N) can be seen posterior to the posterior tibial artery (PTA) and vein (PTV) using a linear transducer placed transversely at the level of the medial malleolus. The nerve typically appears hyperechoic with a honeycomb pattern. (5) Saphenous nerve: it innervates the medial malleolus and a variable portion of the medial aspect of the leg below the knee. This nerve (SAN) travels down the medial leg alongside the great saphenous vein (SV). Because it is a small nerve, it is best visualised 10–15 cm proximal to the medial malleolus using the great saphenous vein as a landmark

Fig. 5

A 39-year-old woman with right mild HV after having undergone percutaneous Reverdin-Isham osteotomy, lateral release and Akin osteotomy for HV correction: (A) antero-posterior radiographic images at preoperative period (1), 3-month follow-up (2) and 6-month follow-up (e). (B) Clinical images at preoperative period (1) and at 6-month follow-up (1–2)

Fig. 6

Graphs showing the patients’ postoperative pain levels, at rest (A) and during movement (B), at different time-points until 6-month follow-up

Fig. 7

Graphs showing the patients’ postoperative satisfaction values (A), and quality of life values (B) at different time-points until 6-month follow-up