A bunion is a progressive enlargement of bone at the base of the big toe joint, often coupled with bone misalignment. A cosmetic concern to some, and a source of intractable pain to others, bunions motivate a large number of elective foot surgeries. Because stability is key to the success of a bunionectomy, fixation techniques, such as surgical pins, have been developed to help preserve it during recovery.
Description
More than 100 surgical procedures have been described for bunion correction. Strictly speaking, a bunionectomy is the surgical removal of the bunion or bony bump only. In practice, however, osteotomies often accompany bunionectomies. In an osteotomy, surgeons cut the bone further up or below the bunion level and reposition it to correct the deformity. They then release the tendons on either side of the big toe joint to keep them from further pulling the toe out of alignment.
Goals
Following a bunionectomy, the shear and bending forces created across the big toe during weight bearing can have a deforming effect on a healing bone. Fixation with pins, screws of k-wires holds the bone in place and helps resist the above deforming forces. Losing your fixation can lead to a loss of bunion correction and an incomplete or faulty union of your bone fragments. Cincinnati orthopedic surgeons Vincent Sammarco and Jorge Acevedo remark that surgical screws offer the greatest resistance to deforming forces. Pins, however, place less stress on bones.
Types
Sammarco and Acevedo argue that pins provide good fixation, with the advantage of being easy to apply and remove. They admit, however, that resistance to deformation can vary with a pin's structure, diameter and stiffness of material. For instance, steel pins are generally superior to bio-absorbable materials. Also, threaded pins have an edge over their smooth counterparts because they prevent "pistoning" of the bone on the pin, which sometimes occurs in mineral-deficient bone. Regardless of the pin type, some doctors prefer two-pin fixation over one-pin, for greater stability.
Follow-Up
A common technique consists in crossing surgical pins placed externally or cut off and buried beneath your skin. One may argue that protruding pins can act as constant reminders to carefully observe home care instructions. The first follow-up visit typically occurs 10 to 14 days after surgery, but pins may remain for as long as six weeks. Periodic x-rays, taken during your recovery period, help ensure that the pins remain in place, enabling your bones to heal in the right position.
Considerations
Putting too much weight on your foot too quickly can compromise a bunionectomy's outcome and aggravate pain and swelling. Recovery therefore occurs in stages, even beyond pin removal. A post-operative shoe gear typically progresses from a negative heel shoe, which allows you to walk without placing pressure on your toes, to a stiff-soled sandal or shoe, to regular shoes, with or without orthotics. Although you may engage in such low-intensity exercise as pleasure walking or swimming right after pin removal, several months may lapse before you can safely resume strenuous sporting activities.
References
- "McGlamry's Comprehensive Textbook of Foot & Ankle Surgery" (Volume 1); Alan Banks, D.P.M. et al.; 2001
- Georgetown University Hospital: Bunionectomy
- "Foot and Ankle Clinics of North America:" Stability and Fixation Techniques in First Metatarsal Osteotomies; Vincent Sammarco, M.D., and Jorge Acevedo, M.D.; September 2001
