Table 1

Clinical and radiographic findings of the patients.

Cobalt-Chrome Group (n = 30)Titanium Alloy Group (n = 34)
VariableMean ± SDRangeMean ± SDRange P Value
Sex, nF: 26, M: 4F: 28, M: 6
Age, y14.6 ± 2.311–1815.5 ± 1.912–180.258
Follow-up, y2.2 ± 0.22–2.42.1 ± 0.42–2.90.833
No. of fused levels11.1 ± 1.210–1311.2 ± 0.810–130.941
Screw density, No. of screws / No. of instrumented vertebrae1.8 ± 0.21.7–21.8 ± 0.11.6–20.912
Lenke lumbar modifier14A, 14B, 2C16A, 15B, 3C0.620
LSM8+, 18N, 4−6+, 22N, 6−0.589
Preoperative MT Cobb’s angle60.3° ± 15.539–96°65.6° ± 10.650–85°0.116
Side-bending correction index, %30.1% ± 22.712–54%32.4% ± 16.317–51%0.652
Ponte osteotomies, % of instrumented levels13.5% (45/333)15.5% (59/381)0.897
Postoperative MT Cobb’s angle16.1° ± 6.17–28°22.8° ± 8.36–38°<0.001a
Coronal correction, %73.6% ± 7.460.3–86.2%65.5% ± 1146.4–88%0.001a
Last FU MT Cobb’s angle, %16.6° ± 6.59–34°23.4° ± 812–36°0.421
Coronal loss of correction at last FU, %0.5° ± 1.4−2 to 5°0.6° ± 1.6−1 to 7°0.816
Preoperative TK19.3° ± 11.95–44°21.6° ± 14.82–50°0.507
 LSM+42.5° ± 1.741–44°45° ± 4.141–50°0.289
 LSM−7.7° ± 1.75–9°4.7 ± 2.52–7°0.021a
Postoperative TK20.6° ± 6.99–32°20.1° ± 6.111–31°0.768
 LSM+25.5° ± 7.519–32°28° ± 2.426–31°0.565
 LSM−15.8° ± 4.69–20°14.7° ± 2.113–17°0.600
Pre- to postoperative TK change1.3° ± 7.6 (6.6%)−12 to 15°1.5° ± 11 (−6.8%)−22 to 14°0.933
 LSM+−17° ± 5.8 (−40%)−22 to 12°−17 ± 1.8 (−37.8%)−19 to 15°0.999
 LSM−8° ± 6 (103.23%)6–15°10° ± 2 (214.29%)8–12°0.038a
Last FU TK21.1° ± 78–34°21.6° ± 7.111–37°0.770
 LSM+27.3° ± 7.919–34°31.3° ± 3.126–31°0.397
 LSM−15.8° ± 5.18–20°13.5° ± 1.511–15°0.171
Postoperative to last FU TK change0.5° ± 1.5 (2.3%)−3 to 4°1.5° ± 3 (7.3%)−2 to 6°0.032a
 LSM+1.8° ± 1.3 (6.9%)0–3°3.3° ± 2.5 (11.9%)−1 to 6°0.282
 LSM−0° ± 0.9 (0%)−1 to 2°−1.2° ± 1 (−8%)−2 to 0°0.060
  • Abbreviations: F, female; FU, follow-up; LMS, Lenke sagittal modifier; M, male; MT, main thoracic; TK, thoracic kyphosis.

  • a Statistically significant (P < 0.05).