The following is a summary of the “Wall thickness analysis method for judging the degree of lower extremity long bone healing,” published in the November 2023 issue of Surgery by Li et al.

This study aimed to explore the potential of utilizing wall thickness analysis as a means to assess the degree of bone healing, offering a quantitative approach to evaluate this process. Patients who suffered lower limb fractures between April 2014 and October 2019 were enrolled and categorized into three groups: bone healing (group A), poor bone healing (group B), and nonunion (group C). Using Mimics 20.0 software and DICOM 3.0 data retrieved from CT scans, three-dimensional models were constructed for the unaffected and affected limbs, post-simulated removal of internal fixation. 

These models represented the primary and simulated phases, respectively. The meshed models were subjected to wall thickness analysis to determine the median wall thickness.

Three ratios, R2 (median wall thickness ratio), R4 (CT value ratio), and R5 (healing index ratio), were calculated by comparing values between the simulated and basic phases. Receiver operating characteristic curve analysis was employed to assess Wall Thickness Analysis’s ability to indicate fracture healing. The study included 112 CT scans from 79 patients, categorized into groups A, B, and C, with frequencies of 49, 37, and 26, respectively.

The median R2 values differed among the groups: group A exhibited a median of 0.91, group B had 0.80, and Group C showed 0.67 (with Group A > Group B > Group C, all P < 0.05). The optimal cutoff point for R2 in predicting bone healing was determined to be 0.84, while for predicting bone nonunion, it was 0.74.

Wall Thickness Analysis demonstrates the potential for quantitatively assessing the state of fracture healing. The median wall thickness ratio emerges as an intuitive and dependable index for evaluating bone healing progression. This study suggests that this analysis method could offer a reliable quantitative means to assess the status of bone healing, providing valuable insights for clinical evaluation.

Source: nature.com/articles/s41598-023-48212-3