Timing of periarticular injection has no effect on postoperative pain and functional recovery in simultaneous bilateral total knee arthroplasty: a prospective randomized, double-blinded trial

Table 1 Patients’ demographic data

Demographic data	Values	P-value
Number of patients	48
Age^a (years)	62.9 ± 5.8
Gender (male: female)	3: 45
BMI^a (kg/m²)	25.9 ± 3.3
Length of stay^a (days)	7.3 ± 1.4
The side of the first operated knee (right: left)	24: 24
The timing of PMDI for the first knee (late: early)	24: 24
Preoperative VAS^a
Late PMDI	6.8 ± 2.5
Early PMDI	6.7 ± 1.9	0.77
Preoperative degrees of active knee flexion^a
Late PMDI	114.6 ± 19.1
Early PMDI	114.9 ± 18.3	0.90

^aData are presented as mean and standard deviation (SD)
Late PMDI, the knees injected with the PMDI before prosthetic implantation as common practice of surgeons
Early PMDI, the knees injected with the PMDI after arthrotomy to prevent neural hypersensitization caused by further soft tissue and bone work during TKA

ISSN: 1471-2474