The Correction Potential of the Lateral Release of the Hallux Valgus: A Comparative Anatomical Study of Minimally Invasive Versus Open Surgical Technique Using a Dorsal Approach

Abstract

Background: Lateral release (LR) is an integral part of surgical correction of hallux valgus. A comparison was made between the open and minimally invasive LR techniques using a dorsal approach. The reliability and safety of the two methods were compared. Besides, the release of specific structures was investigated with special emphasis on ascertaining if the release was partial or a total one.

Methods: In this study on cadavers, LR was performed on nine pairs of foot and ankle specimens. The group assignments were randomized for each case. The operations were followed by anatomical preparation, data collection, photo documentation, and statistical analysis.

Results: A statistically significant advantage was observed with the open dorsal approach as there was a complete release of the adductor hallucis muscle from the lateral sesamoid and the lateral metatarsosesamoid ligament (p = 0.015 in each case). In terms of releasing the adductor hallucis muscle from the proximal phalanx, the lateral joint capsule, and the lateral collateral ligament, none of the investigated procedures showed better performance. However, open dorsal access tends to show a higher degree of release more frequently.

Conclusions: Splitting of the lateral joint capsule, including the lateral collateral ligament and lateral metatarsosesamoid ligament via the dorsal approach can be performed reliably and completely using the open surgical technique. The open dorsal technique shows better rates of detachment when the adductor hallucis muscle is released from the lateral sesamoid. Both techniques resulted in incomplete release of the adductor hallucis muscle from the proximal phalanx.

Study type: Therapeutic-investigating the results of a treatment.

Level of evidence: II (Prospective cohort study).

Supplementary information: The online version contains supplementary material available at 10.1007/s43465-021-00575-3.

Keywords: Foot disorders; Hallux valgus; Lateral release; Minimally invasive surgery.

Fig. 1

Lateral release via an open dorsal access (O-LR). A Dorsal skin incision (white arrow) in the first intermetatarsal space using a scalpel (white star). B The incised lateral joint capsule (white arrow)

Fig. 2

Lateral release (LR) via a minimally invasive dorsal access (M-LR). A Stab incision and split of the lateral joint capsule with a 3 mm Beaver® knife (white arrow) controlled under the image intensifier. B Control of the release by manually applying varisation stress to the first metatarso-phalangeal joint (MTP-I). The lateral aspect of the MTP-I joint opens up (white arrow). Macroscopic image of the procedure as inset in A and B shows a foot specimen with the knife inserted (white arrow)