Table 2. Characteristics of the randomized controlled trials that compared the kinds of anesthesia for orthopedic surgery and their contribution to the meta-analysis.

Study (year)	Anesthesia	n	Surgery	Outcomes studied	Remark
Berggren et al.15	GA	29	Femoral neck fracture surgery	Stroke, cognitive dysfunction, pneumonia	Only fully lucid patients were included in the study
	EA	28
Bigler et al.16	GA	20	Hip surgery	Mortality, cognitive dysfunction	Patients with severe dementia, cancer and psychiatric or disseminated neurological disease were not studied
	SA	20
Casati et al.18	GA	15	Hemiarthroplasty of the hip	Length of hospitalization, cognitive dysfunction	One woman in each group
	USA	15
Davis et al.22	GA	68	Emergency hip surgery	Mortality, stroke, myocardial infarction	General anesthetic technique may not have been the same for all patients
	SP	64
Davis et al.23	GA	279	Hip fracture surgery	Mortality, length of hospitalization	Multicenter study; the length of follow-up was not the same for all patients
	SA	259
Eroglu et al.25	GA	20	Total hip replacement	Blood transfusion requirements	Hypotensive anesthesia was used in both groups
	EA	20
Hole et al.27	GA	31	Total hip arthroplasty	Mortality, myocardial infarction, degree of satisfaction	Only changes in mental status were analyzed, such as amnesia regarding personal data and disorientation relating to time, place and situation
	EA	29
Jones et al.29	GA	72	Elective hip or knee replacement	Mortality, cognitive dysfunction	Patients over the age of 60 years
	SA	74
Juelsgaard et al.30	GA SA	14 15	Hip fracture surgery	Mortality, myocardial infarction, length of hospitalization	The authors quote: "Patients with known coronary artery disease scheduled for osteosynthesis of a femoral neck fracture were included in the study". The exclusion criteria were: uncooperative patients, recent myocardial infarction, unstable angina pectoris, significant aortic stenosis and other established contraindications for spinal anesthesia
McKenzie et al.34	GA	51	Femoral neck fracture surgery	Mortality, myocardial infarction	Patients over the age of 65 years
	SA	49
McLaren et al. 35	GA	29	Femoral neck fracture surgery	Mortality	More patients in the spinal anesthesia group had respiratory problems
	SA	26
Nielson et al. 37	GA	39	Elective knee arthroplasty	Cognitive dysfunction	Patients between 60 and 86 years of age
	SA	25
Racle et al. 38	GA	35	Hip surgery	Mortality, myocardial infarction, stroke, cognitive dysfunction	The patients were women
	SA	35
Riis et al. 39	GA	10	Total hip replacement arthroplasty	Cognitive dysfunction	The authors reported data from a third group with GA and EA combined
	EA	10
Valentin et al.41	GA		Hip fracture surgery	Mortality	Premedication was not given to high-risk patients; there were more high-risk patients in the spinal anesthesia group
	SA
White et al.42	GA	20	Femoral neck fracture surgery	Mortality, cognitive dysfunction, pneumonia	Patients in the spinal anesthesia group received general anesthetic drugs reported as "light anesthesia"
	SA	19
Williams-Russo et al.44	GA	134	Total knee replacement	Mortality, length of hospitalization, cognitive dysfunction	The authors developed their own questionnaire to evaluate cognitive dysfunction
	EA	128