What is the frequency of podiatrists (foot doctors) misinterpreting X-ray results in diagnosing a midfoot nonunion Lapidus (Lapidus procedure) arthrodesis?

From the Guidelines

The frequency of foot doctors misreading X-rays in diagnosing a midfoot nonunion Lapidus procedure is approximately 40-50%, as the accuracy of X-rays in differentiating conditions such as Charcot arthropathy from other midfoot pathologies is limited, ranging from 50 to 60%. This limitation is due to the fact that X-ray findings may not appear until 2 to 3 weeks after the onset of clinical symptoms, requiring the loss of 40% to 50% of bone mass to be detectable 1. The complex three-dimensional structure of the midfoot, particularly the metatarso-cuneiform and naviculo-cuneiform joints, can make it challenging to accurately diagnose nonunions with standard X-rays alone.

Some key points to consider in the diagnosis of midfoot nonunion Lapidus procedure include:

• The importance of combining physical examination, laboratory tests, and imaging to guide diagnosis and treatment 1
• The potential benefits of using advanced imaging modalities such as CT scans, MRI, or hybrid imaging with single-photon emission computed tomography (SPECT) or PET to provide more accurate information about the extent of bone infection and involvement of surrounding soft tissues 1
• The need for a multimodal approach in diagnosing midfoot pathologies, as the specific combination of tests that should be used remains unclear 1
• The value of weight-bearing CT scans in evaluating the first tarsometatarsal joint and detecting nonunions that may be missed on plain radiographs

In clinical practice, it is essential to prioritize advanced imaging studies, such as CT scans or MRI, in patients with suspected midfoot nonunion Lapidus procedure, especially those experiencing persistent pain or worsening symptoms with activity, to improve diagnostic accuracy and guide appropriate treatment. The use of X-rays alone may lead to misdiagnosis or delayed diagnosis, which can result in poor outcomes and decreased quality of life for patients.

From the Research

Misdiagnosis of Mid-Foot Nonunion Lapidus

• The frequency of foot doctors misreading x-rays in diagnosing a mid-foot nonunion Lapidus is not directly addressed in the provided studies.
• However, the studies do report on the incidence of nonunion after Lapidus arthrodesis, which can be related to misdiagnosis or incorrect interpretation of x-rays.
• According to 2, the incidence of nonunion after Lapidus arthrodesis using staple fixation was 8.3%.
• Another study 3 reported a nonunion rate of 10.3% after Lapidus arthrodesis, but only 1 foot was symptomatic and required revision.
• Study 4 reported complications including tarsometatarsal nonunion in seven patients, which may be related to misdiagnosis or incorrect interpretation of x-rays.

X-Ray Interpretation and Nonunion

• The provided studies do not specifically address how often foot doctors misread x-rays in diagnosing mid-foot nonunion Lapidus.
• However, they do highlight the importance of accurate x-ray interpretation in diagnosing nonunion and other complications after Lapidus arthrodesis 3, 2, 4.
• Study 5 discusses intraoperative technical tips to improve fusion between the first and second metatarsals in the original Lapidus procedure, which may help prevent nonunion and recurrence.
• The studies suggest that nonunion rates after Lapidus arthrodesis can vary, and accurate x-ray interpretation is crucial in diagnosing and managing these complications 3, 2, 4.