Table 2 Patient characteristics after PSM categorized by the time of correction

Age at Nuss repair, year, median

24

25

0.141

Age at removal bar, year, median

28

33

< 0.001

Sex, male, n (%)

30 (93.8)

30 (93.8)

NA

BMI, median

20.4

20.9

0.652

HI (CT) before repair, median

4.08

4.19

0.214

Bar number, 2 or 3 (%)

26 (81.2)

24 (75.0)

0.123

Duration of correction years, median (range)

4.2 (3.0–5.9)

8.0 (6.0–16.2)

< 0.001

Callus formation, n (%)

15 (46.9)

22 (68.8)

0.029

Operation time, min, median (range)

55 (40–100)

85 (45–210)

0.026

Blood loss, mL, median (range)

10 (10–50)

35 (10–120)

0.017

Hospital stay, days, median (range)

2 (2–3)

2 [2–5]

0.349

Complications

2 (6.3)

3 (9.4)

0.648

HI (CXR) before repair, median

3.83

3.95

0.408

HI (CXR) before removal, median

2.85

2.92

0.398

HI (CXR) after removal, median

2.98

3.12

0.308

Improvement after repair (%), median

21.0

22.2

0.132