A bunion is a common foot deformity where the big toe drifts toward the smaller toes, causing a bony bump to form on the joint at the base of the big toe. This misalignment can lead to persistent pain, inflammation, and difficulty wearing normal footwear. When non-surgical treatments like wider shoes, padding, and orthotics fail, surgical correction becomes necessary. Minimally Invasive Bunion Surgery (MIBS) is a modern approach to addressing this condition.
Defining Minimally Invasive Bunion Surgery
Minimally Invasive Bunion Surgery (MIBS) corrects the foot deformity through several small, “keyhole” incisions, contrasting with the single, long incision used in traditional open surgery. These tiny cuts, typically 3 to 5 millimeters, result in less trauma to surrounding soft tissues like the skin and joint capsule. This reduced tissue disruption is the core principle of MIBS, leading to less post-operative pain and reduced scarring.
The surgeon does not directly visualize the bone through a large opening. Instead, MIBS relies on specialized instruments and continuous fluoroscopic guidance, a real-time X-ray imaging system. High-speed burrs are inserted through the small incisions to perform the necessary bone work. This ensures precise bone alignment correction while minimizing disturbance to the soft tissue envelope.
The reduced soft tissue damage provides benefits like decreased swelling, a lower risk of stiffness, and often a quicker initial recovery compared to the open technique. The less invasive nature of the procedure often allows it to be performed on an outpatient basis, letting the patient return home the same day.
The Surgical Procedure
The MIBS procedure involves performing an osteotomy, which is cutting and repositioning the metatarsal bone to straighten the big toe. The surgeon makes a few small stab incisions to access the bone. A specialized, water-cooled burr is then inserted through these portals to make precise cuts.
Using real-time X-ray guidance, the surgeon shifts the metatarsal head laterally to realign it. This realignment corrects the underlying structural deformity. Once the bone is repositioned, it must be stabilized to ensure proper healing.
Fixation is typically achieved using small metallic hardware, such as screws or implants, inserted through the tiny incisions. These devices hold the corrected bone fragments firmly in place. The process focuses on achieving the proper angular correction to reduce the protruding bump and restore foot function.
Patient Eligibility and Selection
Determining candidacy involves assessing the deformity’s severity, the patient’s overall health, and the joint condition. MIBS is generally considered an ideal choice for patients with mild to moderate bunion deformities. In these cases, the less invasive approach provides sufficient correctional power with the benefits of reduced tissue trauma.
Patients with very severe deformities, where the big toe has significantly shifted, may require a traditional open procedure for adequate structural correction and stability. Specific contraindications can also disqualify a patient from MIBS.
These contraindications include significant arthritis or joint degeneration in the big toe, which might necessitate joint fusion or replacement. Patients with poor bone quality, such as severe osteoporosis, or active foot infections are typically not suitable candidates. The surgeon must also consider previous foot surgeries or underlying conditions like hypermobility. A detailed physical examination and weight-bearing X-rays are necessary to confirm if the deformity is appropriate for the minimally invasive approach.
Immediate Post-Operative Care and Recovery Timeline
Due to minimal soft tissue damage, many patients are permitted to bear weight immediately or very early on, using a specialized post-operative shoe or boot. This protective footwear safeguards the surgical site and maintains corrected alignment while the bone begins to fuse.
Pain and swelling are common initially but are generally less intense than with traditional surgery. They are managed with oral pain medication and elevation. Patients should keep their foot elevated above the heart during the first one to two weeks to minimize swelling. Gentle range-of-motion exercises for the big toe are often started early to prevent joint stiffness.
Most patients transition from the surgical shoe into supportive, wide-toe athletic shoes within two to four weeks. Light activities, such as walking, can be resumed, though strenuous exercise is avoided. Bone healing typically takes six to eight weeks. A full return to all regular activities, including higher-impact exercise, usually occurs around the three-month mark. Follow-up appointments, including X-rays, monitor healing progress and guide the patient’s return to activity.