The analgesic efficacy and safety of peri-articular injection versus intra-articular injection in one-stage bilateral total knee arthroplasty: a randomized controlled trial

Table 1 Baseline Characteristics of the Patients*

Characteristic	Peri-articular Injection	Intra-articular Injection	P value
Female, n (%)	55 (91.6)
Age—yr mean [95%CI]	65.8 [64.0, 67.6]
Body mass index† − -kg/m² mean [95%CI]	27.7 [26.7, 28.8]
Ethnics, n (%)
Han	56 (93.3)
Minority‡	4 (6.7)
Diagnosis, n (%)
Osteoarthritis	56 (93.3)
Rheumatoid arthritis	4 (6.7)
ASA grade, n (%)
I	3 (5.0)
II	53 (88.3)
III	4 (6.7)
IV	0
Numerical rating scale at rest mean [95%CI]	0.16 [0.04, 0.28]	0.20 [0.04, 0.35]	0.855
Numerical rating scale during activity mean [95%CI]	5.25 [4.87, 5.62]	4.98 [4.51, 5.45]	0.317
Range of motion actively§ mean [95%CI]	94.8 [93.3, 96.2]	94.0 [92.7, 95.4]	0.453
Range of motion passively ¶ mean [95%CI]	115.9 [114.2, 117.5]	114.0 [112.4, 115.6]	0.103

* No significant differences between groups in the reported characteristics were found at baseline
† The body-mass index is the weight in kilograms divided by the square of the height in meters
‡ Four patients are Chinese minorities, including two Manchu and two Mongols
§ Range of motion actively is patients bending knees by themselves
¶ Range of motion passively is physicians bending patients’ knees

ISSN: 1471-2253