A cone beam CT based 3D-assessment of bony forefoot geometry after modified Lapidus arthrodesis

First Metatarsal Rotation in Hallux Valgus Deformity

“… Abbreviations: CI, confidence interval; CT CAD, computed tomography computer-aided design; HV, hallux valgus; nr, not reported; NWBR, nonweightbearing radiography; SD, standard deviation; QUACS, Quality Appraisal for Cadaveric Studies; QUADAS, Quality Assessment of Diagnostic Accuracy Studies 2; WBCT, weightbearing computed tomography; WBR, weightbearing radiography. a Studies imaging cadavers are marked with a (C); studies imaging patients are marked with a (P). b Eustace et al reported M1 rotation as a categorical variable with 0-, 10-, 20-, and 30-degree rotational classifications. c Denotes statistically significant difference in M1 rotation between groups. d Scheele et al 70 reported M1 rotation among HV patients preoperatively (HV Group) and postoperatively (Control Group). Patient imaging studies showing a low-risk designation in the Patient Selection, Index Test, Reference Standard, and Flow and Timing QUADAS-2 sections were designated “low risk.” If any of these categories were unclear, “unclear risk” was reported. All studies were found to be applicable according the QUADAS Criteria. …”

“…Four investigations used axial sesamoid view radiographs as the imaging modality of choice, with either nonweightbearing (NWBR) 71 or weightbearing (WBR) conditions. 30,57,67 Three studies used weightbearing computed tomography (WBCT), 11,45,70 and 3 used computer-aided design (CAD) models extracted from WBCT imaging to measure the M1 rotation. 9,16,62 Illustrations and methodology of the described measurement techniques are reported in Figure 2.…”

“…Scheele et al 70 reported M1 rotation among HV patients preoperatively (HV Group) and postoperatively (Control Group).…”

“…In one of the first studies to measure M1 pronation perioperatively using WBCT, Scheele utilized a WBCT axial panorama view. 70 This imaging perspective was used to enable the measuring of 3 angles, termed A1-3, where the A3 angle was used to quantify M1 rotation. This angle was found to be significantly reduced in HV patients following a first metatarsocuneiform arthrodesis (“modified Lapidus”) procedure.…”

“…This angle was found to be significantly reduced in HV patients following a first metatarsocuneiform arthrodesis (“modified Lapidus”) procedure. 70…”