Preoperative planning of Cam-type femoroacetabular impingement using spherical fitting technique in CT three-dimensional reconstruction / 中华骨科杂志

ABSTRACT

Objective:To explore the feasibility and effect of applying spherical fitting technology in CT three-dimensional reconstruction in preoperative planning of the resection range of Cam-type femoral acetabular impingement (FAI).Methods:46 Cam-type FAI patients who underwent arthroscopic femoroplasty in the Department of Sports Medicine in the Third Affiliated Hospital of Southern Medical University from July 2020 to June 2022 were enrolled in the spherical fitting group, including 26 females and 20 males, with an average age of 38.4±15.2 years (range of 24-53 years). The preoperative planning was performed using spherical fitting technology in CT three-dimensional reconstruction. Another 42 Cam-type FAI patients who underwent arthroscopic femoroplasty from July 2018 to June 2020 were enrolled in the observation group, including 25 females and 17 males, with an average age of 43.6±18.4 years (range 24-61 years). The preoperative planning was performed using CT three-dimensional reconstruction observation method. This study evaluated the impact of femoroplasty planned by spherical fitting technique on patients' prognosis though comparing the differences of postoperative α angle, femoral head-neck offset ratio, modified Harris hip score (mHHS), and visual analog score (VAS) at 3, 6, 9, and 12 months between two groups.Results:The average follow-up time was 11.8±0.6 months in spherical fitting group and 11.3±0.8 months in observation group. There was no significant difference regarding α angle, femoral head-neck offset ratio, mHHS, and VAS between two groups preoperatively ( P>0.05). The mHHS in two groups increased gradually, while VAS decreased sequentially at 3, 6, 9, and 12 months postoperatively. The postoperative mHHS and VAS were significantly better than those before surgery ( P<0.05). The mHHS was 83.2±14.8 vs. 70.5±11.2 in spherical fitting group and observation group at the followup of 9 months with significant difference ( t=4.471, P=0.007). It was 85.7±13.3 vs. 73.2±12.5 at the followup of 12 months with significant difference ( t=4.596, P=0.008). No significant difference was found in α angle, femoral head-neck offset ratio or mHHS at 3 and 6 months postoperatively ( P>0.05), and no significant difference was found in VAS at 3, 6, 9, and 12 months postoperatively between two groups. Conclusion:The spherical fitting technology in CT three-dimensional reconstruction could assist surgeons with planning of the resection range of Cam deformity preoperatively, and achieve a smooth progress of arthroscopic femoroplasty intraoperatively; after short term follow-up, we found that patients who underwent femoroplasty using this technology achieved satisfactory outcomes.