Scarf Osteotomy for Hallux Valgus
By Dr Ooi Lai Hock



Introduction
One of the most common major elective foot and ankle operation is hallux valgus surgery for painful bunions. There are many surgical techniques in orthopaedic textbooks and literature to correct bunions. For example, there are more than 100 ways to treat hallux valgus surgically. In my experience and hands, I find that the most reliable and reproducible surgical technique is the Scarf osteotomy for hallux valgus.

I will describe the technique and advantages of the Scarf osteotomy below. I will also provide you with the results and pictures of patients under my care. With this technique, immediate full weight bearing with an orthotic is allowed. This is a vast change from other techniques whereby patients are kept in a cast and not allowed to weight-bear for weeks. Nearly all patients find this extremely important as it is certainly more convenient and acceptable.


Scarf Osteotomy for Hallux Valgus
This technique provides a more robust reconstruction of the 1st metatarsal osteotomy. The philosophy behind this technique was adopted from carpentry. A Z-cut is made in the 1st metatarsal which adds to increased stability between the cut bones. The addition of screws to the 1st metatarsal vastly improves the stability.


Scarf Carpentry vs Scarf Osteotomy

Figure 1 refers to the Scarf or Z-cut in carpentry. Figure 3 shows the Scarf osteotomy of the 1st metatarsal.


Advantages

  1. Immediate stability allows for full weight bearing with an orthotic sandal after surgery.
  2. No cast needed at all.
  3. Mild pain post-op (Pain scores typically 1-3/10 with analgesia).
  4. Lower risk of avascular necrosis of the 1st metatarsal head, nonunion, transferred metatarsalgia compared with other techniques to correct hallux valgus surgically.

 

Results
Mean scores for the SF-36 and American Orthopaedic Foot & Ankle Society (AOFAS) Forefoot scores in 17 patients in one series showed a significant improvement over time in the table below.


Clinical Example

Pre-op Post-op Full weight bearing with orthotic sandals immediately after surgery

     


References:

  1. MY Tan, LH Ooi. Outcome of scarf osteotomy for hallux valgus. Does restoration of x-ray parameters matter? Study in progress.