From the Research
Doctors frequently disagree on the diagnosis of a nonunion one year after a Lapidus bunionectomy, with the most recent study suggesting a nonunion rate of 9.01% among patients who underwent the modified Lapidus procedure 1. This disagreement stems from the challenges in defining and identifying nonunion in first tarsometatarsal arthrodesis procedures. Some key points to consider include:
- Radiographic evidence can be difficult to interpret, as partial fusion or delayed union may appear similar to nonunion on X-rays or CT scans.
- Clinical assessment also varies, as some patients with radiographic nonunion remain asymptomatic while others with apparent fusion still experience pain.
- The definition of nonunion itself lacks standardization, with some physicians requiring complete absence of bone bridging, while others consider persistent pain and motion at the fusion site as diagnostic criteria.
- Patient factors further complicate diagnosis, as comorbidities like diabetes, smoking history, or osteoporosis can affect both healing rates and imaging interpretation.
- A study from 2020 found that nonunion of the first MTC joint occurred in 10.3% of patients who underwent Lapidus bunionectomy, but only 1 foot was symptomatic requiring revision 2.
- Another study from 2022 identified risk factors for nonunion, including previous bunionectomy, increased body mass index, and increased preoperative HV angle 1. For patients concerned about potential nonunion, seeking a second opinion from a foot and ankle specialist is reasonable, particularly if experiencing persistent pain or functional limitations despite radiographic findings. Some important considerations for diagnosis and treatment include:
- Careful evaluation of radiographic and clinical evidence
- Consideration of patient factors and comorbidities
- Standardization of the definition of nonunion
- Collaboration with a foot and ankle specialist for complex cases.