Table 2.

The NRS score of the patient at the preoperative and postoperative in each time period (mean ± SD)

Time	n	Preoperative	Postoperative	p value
T1	42	5.90 ± 0.69	2.86 ± 2.08	< 0.001
T2	41	6.15 ± 0.79	3.49 ± 2.55	< 0.001
T3	39	5.85 ± 0.67	3.36 ± 2.42	< 0.001
T4	29	5.69 ± 0.71	3.28 ± 1.93	< 0.001
T5	21	5.95 ± 0.67	3.67 ± 2.31	< 0.001
T6	23	5.91 ± 0.67	3.30 ± 2.06	< 0.001
T7	10	6.00 ± 0.94	3.50 ± 2.95	0.008
T8	11	6.00 ± 0.89	4.18 ± 2.44	0.008
T9	8	5.88 ± 0.64	3.75 ± 2.96	0.049
T10	4	6.00 ± 0.82	4.25 ± 2.63	0.188

T1 within 1 year after surgery, T2 between 1 and 2 years after surgery, T3 between 2 and 3 years after surgery, T4 between 3 and 4 years after surgery, T5 between 4 and 5 years after surgery, T6 between 5 and 6 years after surgery, T7 between 6 and 7 years after surgery, T8 between 7 and 8 years after surgery, T9 between 8 and 9 years after surgery, T10 between 9 and 10 years after surgery