Surgical and long-term functional outcomes of patients with Duchenne muscular dystrophy following spinal deformity correction

Table 4 Correlation between clinical, operative, and both preoperative and postoperative radiographic variables with patient-reported Muscular Dystrophy Spine Questionnaire total scores: Quantitative clinical, operative and radiographic variables were assessed for correlation with Muscular Dystrophy Spine Questionnaire total scores by linear regression analysis; standardised coefficients are displayed

Clinical/radiological variable	Value/coefficient estimate (95%CI)	P value
Clinical/Operative parameters
Postoperative follow-up (yr)	-0.766 (-1.138, -0.394)	0.001a
Age (yr)	-0.651 (-1.086, -0.216)	0.006a
Age at loss of independent ambulation (yr)	0.496 (0.127, 0.865)	0.013a
Age at surgery (yr)	-0.146 (-0.519, 0.227)	0.410
Preoperative gastrostomy (Y/N)1	-0.036 (-1.072, 1.001)	0.941
Preoperative NIV use (Y/N)1	0.110 (-0.731, 0.951)	0.777
Duration of surgery (minutes)	-0.030 (-0.603, 0.543)	0.911
Intraoperative blood loss (%, TBV)	-0.297 (-0.841, 0.247)	0.257
Instrumented fused to pelvis (Y/N)1	0.542 (-0.221, 1.306)	0.145
Length of ICU stay (days)	0.123 (-1.010, 1.255)	0.817
Length of stay in hospital (days)	-0.535 (-1.663, 0.593)	0.322
Postoperative complications (Y/N)1	0.010 (-0.703, 0.723)	0.975
Preoperative radiographic parameters
Scoliosis (Cobb angle) (°)	0.268 (-5.330, 5.867)	0.907
Scoliosis on traction radiographs (Cobb angle)	-2.771 (-9.706, 4.164)	0.351
Scoliosis flexibility index (%)	-2.797 (-6.952, 1.359)	0.144
Pelvic obliquity (°)	-0.531 (-4.784, 3.723)	0.761
Pelvic obliquity on traction radiographs (°)	1.036 (-4.511, 6.582)	0.651
Pelvic obliquity flexibility index (%)	1.368 (-2.465, 5.200)	0.401
Lumbar lordosis (T12-S1; °)	0.346 (-1.880, 2.571)	0.706
Thoracic kyphosis (T5-T12; °)	0.153 (-2.283, 2.589)	0.878
Sagittal balance (C7PL, cm)	0.533 (-1.041, 2.106)	0.424
Coronal balance (C7PL, cm)	0.213 (-1.401, 1.828)	0.748
Postoperative radiographic parameters
Scoliosis (Cobb angle) (°)	-3.005 (-4.718, -1.292)	0.004a
Correction of scoliosis (%)	2.167 (1.053, 3.282)	0.002a
Pelvic obliquity (°)	0.367 (-0.765, 1.499)	0.468
Correction of pelvic obliquity (%)	0.433 (-0.263, 1.129)	0.185
Lumbar lordosis (T12-S1; °)	-0.642 (-1.184, -0.100)	0.027a
Thoracic kyphosis (T5-T12; °)	0.043 (-0.345, 0.430)	0.802
Sagittal balance (C7PL, cm)	-0.190 (-0.768, 0.389)	0.464
Coronal balance (C7PL, cm)	0.886 (-0.215, 1.987)	0.099

¹Indicates qualitative variable.

^aIndicates statistically significant result (P < 0.05).

L: Luque sublaminar wires; C7PL: C7 plumb line; NIV: Non-invasive ventilation; TBV: Total blood volume; ICU: Intensive care unit.