The Chevron osteotomy stands as one of the most widely performed and well-established surgical procedures for the correction of mild to moderate hallux valgus, commonly known as bunions. This distal metatarsal osteotomy, characterized by its distinctive V-shaped cut, has evolved over decades to become a cornerstone technique in foot and ankle surgery, offering predictable outcomes with relatively low complication rates when applied to appropriate cases.
Understanding Bunions and Surgical Indications
Hallux valgus represents a complex three-dimensional deformity of the first metatarsophalangeal joint, characterized by lateral deviation of the great toe and medial deviation of the first metatarsal head. This progressive condition affects approximately 23% of adults aged 18-65 and up to 36% of those over 65, causing pain, difficulty with footwear, and cosmetic concerns. While conservative measures including wider shoes, padding, and orthotic devices may provide symptomatic relief, surgical intervention becomes necessary when pain significantly impairs quality of life and non-operative treatments have failed.
The Chevron osteotomy is specifically indicated for mild to moderate bunion deformities, typically defined as an intermetatarsal angle between 11 and 16 degrees and a hallux valgus angle less than 40 degrees. Patients with severe deformities, significant arthritis, or elderly individuals with poor bone quality may require alternative procedures. The ideal candidate is a healthy patient with good bone quality, realistic expectations, and symptomatic bunion deformity that interferes with daily activities.
Surgical Technique and Biomechanical Principles
The Chevron osteotomy derives its name from its V-shaped configuration, which resembles the military insignia. The procedure involves creating a 60-degree V-shaped cut in the distal first metatarsal head, with the apex positioned at the center of the metatarsal head. This geometric design provides inherent stability while allowing for lateral displacement of the metatarsal head to correct the deformity.
The surgical approach typically begins with a medial incision over the first metatarsophalangeal joint. After careful dissection and protection of neurovascular structures, the medial eminence prominence is exposed. The surgeon then creates the characteristic V-shaped osteotomy using an oscillating saw, with the dorsal and plantar arms of the osteotomy extending proximally at equal angles. The distal capital fragment is then translated laterally, typically 3-5 millimeters, to reduce the intermetatarsal angle and realign the metatarsal head over the sesamoid bones.
The medial eminence is resected flush with the medial cortex of the metatarsal shaft, removing the bony prominence that characterizes the bunion deformity. The osteotomy is secured using various fixation methods, most commonly a single or double screw fixation, though some surgeons utilize Kirschner wires or absorbable pins. The medial capsule is then carefully repaired and imbricated to provide additional soft tissue stabilization.
Biomechanical Advantages
The Chevron osteotomy offers several biomechanical advantages that contribute to its widespread adoption. The V-shaped configuration creates a large surface area of bone contact, promoting rapid healing and inherent stability. The interlocking nature of the osteotomy resists dorsal and plantar displacement, reducing the risk of malunion. Additionally, the distal location of the cut preserves blood supply to the metatarsal head, minimizing the risk of avascular necrosis.
The procedure effectively addresses the fundamental deformity by lateralizing the metatarsal head, thereby reducing the intermetatarsal angle and improving weight distribution across the forefoot. The geometric design allows for predictable correction while maintaining the overall length of the first metatarsal, preserving proper biomechanics of the first ray. This preservation of length is crucial for maintaining appropriate pressure distribution during gait and preventing transfer metatarsalgia.
Clinical Outcomes and Evidence
Extensive research has demonstrated the efficacy of the Chevron osteotomy for appropriate bunion deformities. Patient satisfaction rates consistently exceed 85-90%, with significant improvements in pain scores and functional outcomes. Radiographic studies show reliable correction of the hallux valgus angle and intermetatarsal angle, with most series reporting recurrence rates below 10% when proper patient selection criteria are followed.
The procedure typically allows for early protected weight-bearing in a surgical shoe, with most patients returning to regular footwear within 6-8 weeks and resuming full activities by 3-4 months. The relatively short recovery period compared to more extensive procedures represents another significant advantage for appropriate candidates.
Complications and Limitations
While generally safe and effective, the Chevron osteotomy carries potential complications that must be discussed with patients. Avascular necrosis of the metatarsal head occurs in approximately 0-20% of cases across various studies, though symptomatic cases requiring revision are rare. Other potential complications include recurrence of deformity, hallux varus (overcorrection), transfer metatarsalgia, infection, nonunion, and nerve injury.
The primary limitation of the Chevron osteotomy lies in its corrective power. Because it is a distal osteotomy with limited translation capability, it cannot adequately correct severe deformities with intermetatarsal angles exceeding 16 degrees. Attempting to use this procedure for inappropriate cases increases the risk of recurrence and complications. Surgeons must carefully assess each patient’s deformity and select the appropriate procedure accordingly.
The Chevron osteotomy represents a time-tested, reliable solution for mild to moderate bunion deformities. Its elegant geometric design, inherent stability, predictable outcomes, and relatively low complication profile have established it as a gold standard in bunion surgery. Success depends critically on appropriate patient selection, meticulous surgical technique, and realistic patient expectations. When performed by experienced surgeons for properly indicated cases, the Chevron osteotomy continues to provide excellent pain relief, functional improvement, and patient satisfaction, maintaining its position as a cornerstone procedure in the armamentarium of foot and ankle surgeons worldwide.