Although the term anatomic dissection is commonly accepted as a surgical philosophy for most podiatric surgeons, it actually encompasses all aspects of the surgical technique from incision placement to wound closure. The primary objectives of an anatomic approach in hallux valgus surgery include the surgeon’s ability to execute the procedure with control and consistency in the wide variety of anatomic variations encountered, to reduce complications, and to be able to identify and manage unique problems that may require special skills or techniques for a successful surgical repair.

An anatomic approach is employed in all key areas of the surgical technique:

The underlying concept of anatomic dissection is the preservation of blood supply (and innervation) to the soft tissues during surgery. The incision placement is oriented parallel to and between any critical structures. The dissection of the subcutaneous tissues is the fundamental basis of anatomic dissection. The superficial soft tissues (those external to the deep fascia) must be reflected in a manner that preserves the skin and subcutaneous layers and avoids disruption of the laminar contact of these two layers and the linear structures they contain. This approach not only maintains the viability and healing potential of these tissues, but it also serves as the primary mechanism of establishing hemostasis of the surgical wound, whether the procedure is performed with or without a tourniquet. The primary control of bleeding both during and after the surgical procedure is most effectively accomplished with the anatomic dissection technique. This is key to reducing bleeding, hematoma, and edema. In addition to improved soft tissue healing, tissue plane dissection maintains a distinct separation of the superficial and deep tissues even after the healing process has occurred. Minimal scar and adhesion between the layers enhance delamination of tissue planes should revisional surgery become necessary.

Another critical function of the surgical dissection is exposure. Whereas adequate exposure is usually related to the length of the incision, the exposure provided with anatomic dissection creates full visualization of all aspects of joint anatomy without excessive retraction or tension on the surrounding soft tissues. The “universal” dorsal medial incision allows for direct visualization of both medial and lateral aspects of the joint and their related components without the need for excessive retraction or a second incision.

Full surgical exposure allows for critical evaluation of normal as well as pathologic anatomy around the first metatarsophalangeal joint. Direct visualization of the key anatomic components of the joint, especially within the intermetatarsal space, allows the surgeon to assess the structures influencing joint motion and facilitates the release, resection, or other manipulations of each of these structures.

The initial goals of the anatomic dissection process are to provide access to the surgical area, to establish hemostasis, to identify and release any significant soft tissue contracture, and to prepare for the “osseous” aspect of the surgical process. Once the structural aspect of hallux valgus repair has been performed, the procedure is completed with a repair and balancing of the periarticular soft tissue components. This includes refined capsulorrhaphy and tendon transfer techniques performed to establish a balance of function around the first metatarsophalangeal joint axis. This final repair process and the osseous realignment of the first ray are the keys to a successful and long-lasting surgical result.

Before the actual incision, the perioperative area may be infiltrated with a local anesthetic agent. Hemostasis may be achieved without the use of a tourniquet by the addition of epinephrine to the solution. A common technique is to combine a shortacting and long-acting local anesthetic, usually equal volumes of lidocaine with epinephrine (1:100,000) and bupivacaine. This technique may be performed whether the patient is maintained under general anesthesia or with intravenous sedation. In addition to the augmentation of anesthesia, the epinephrine provides hemostasis through reduced capillary bleeding. Local infiltration of epinephrine-containing solutions has been shown to be safely used in combination with most modern general anesthetic techniques (17,18,19,20,21,22,23,24 and 25). This approach, along with the primary hemostasis established with anatomic dissection, allows the procedure to be performed without a tourniquet.

However, tourniquets represent an effective means of achieving hemostasis and are favored by many surgeons. Ankle, calf, and midthigh devices can be used safely when they are employed within commonly recognized guidelines (26,27,28 and 29). Although complications may arise from the use of tourniquets, the incidence is low (30,31,32,33,34,35,36,37,38,39,40,41,42 and 43).

Complete anesthesia at the surgery site with the infiltration of local anesthetic also allows the patient to be maintained with a lower level of intravenous sedation or general anesthesia. This approach may reduce potential side effects from the narcotic and neuroleptic agents used in sedative and general anesthesia. Investigators have suggested that a preemptive effect may be obtained that would improve the patient’s postoperative course by decreasing pain (44,45).

Strategic placement of the surgical incision can greatly enhance the surgeon’s ability to access adequately critical aspects or regions of the first metatarsophalangeal joint. Although the first metatarsophalangeal joint can be exposed through many different surgical approaches (46,47,48,49,50,51 and 52), a universal incision for hallux valgus surgery can be oriented along the dorsal medial aspect of the metatarsophalangeal joint and follows the angle of the primary deformity. The incision begins proximally about the midshaft level of the dorsal medial aspect of the metatarsal, extends distally to the dorsal medial aspect of the metatarsal head, and ends just proximal to the hallux interphalangeal joint, medial to the extensor hallucis longus tendon. This primary incision should extend equidistant from the center of the metatarsal head to allow for ease of retraction in exposure of both the medial and lateral aspects of the metatarsophalangeal region. The incision usually lies between the extensor hallucis longus tendon and the dorsal medial neurovascular structures. The incision technique is usually controlled depth, to allow for separation of the dermis without violation of underlying subcutaneous vessels.

Manipulation of the subcutaneous layer is the key step in anatomic dissection. The subcutaneous layer is initially divided in the line of the primary skin incision and then is separated from the surface of the deep fascia around the dorsal, medial, and lateral aspects of the metatarsophalangeal joint. This enhances surgical hemostasis, preserves the viability of the surrounding tissues, and minimizes the risk of postoperative edema, hematoma, and other wound complications.

The subcutaneous layer, or superficial fascia, is actually composed of two tissue layers between which the cutaneous vessels and nerves traverse. The outer fatty layer, or panniculus adiposus, contains the venous tributaries and is attached to the deep fascia by a thin, membrane-like film (53). This membrane attachment creates the dissection plane to be followed when separating the superficial fascia from the deep fascia in anatomic dissection or tissue plane separation. Accurate and clean separation of the superficial fascia from the deep fascia preserves the cutaneous neurovascular structures.