Zhu 2011.

Study characteristics
Methods	Method of randomisation: computer‐generated random numbers list reviewed by nurse before surgery Assessor blinding: no, but mention of independent observer Loss to follow‐up at 3 years: 6/57 (5 lost to follow‐up; 1 died)
Participants	Beijing Ji Shui Tan Hospital, Beijing, China Period of study recruitment: November 2004 to December 2006 57 skeletally‐mature participants with an acute 2‐part surgical neck fracture of the proximal humerus (Neer's classification) treated surgically within 21 days of the injury. Participant consent Exclusion criteria: open physes; fracture and displacement involving the greater or lesser tuberosity or extension of the fracture line distally beyond the deltoid tubercle; associated musculoskeletal injuries to the same upper extremity; open fracture; and prior surgery on the affected shoulder Of 51 followed up: 34 female, 17 male; mean age 53 years
Interventions	Interventions started: surgery on average 9 days after injury (randomisation before surgery). 1. Open reduction with internal fixation using a locking plate: Locking Proximal Humeral Plate (LPHP; Synthes) or PHILOS (Synthes). General anaesthesia combined with an interscalene block. Indirect reduction under image intensifier, with reduced fracture temporarily fixed by a Kirschner wire. After placement, position of the locking plate checked with the image intensifier intraoperatively, and the plate was fixed with locking screws. Finally, a thorough fluoroscopic screening was done to ensure that no screw was penetrating the articular surface of the humeral head. 2. Open reduction with internal fixation using a locking nail: the Proximal Humeral Nail (PHN; Synthes). An interscalene brachial plexus block was used. Nail was inserted under image control without reaming after the fracture was fully reduced. After insertion of the spiral blade and the distal locking screws, an end cap was screwed in to lock the spiral blade. The rotator cuff tendon and the deltoid were carefully repaired during wound closure. The affected extremity was protected by a sling for six weeks postoperatively. Passive range‐of‐motion exercises, supervised by a physical therapist, were initiated on the first postoperative day. Active and active‐assisted exercises began after six weeks, when early callus formation could be seen on radiographs. Strengthening exercises were started three months after the surgery. Assigned: 29/28 Completed (at 3 years): 26/25
Outcomes	Length of follow‐up: 3 years (also 1 year) ASES (American Shoulder and Elbow Surgeons) score Constant score (both shoulders) Pain (VAS) Mortality Complications (overall, infection (none), heterotopic ossification, screw penetration, pseudothorax) Reoperation Range of motion (active flexion, external rotation, internal rotation) Strength Duration of surgery Blood loss and transfusion Radiographic outcomes, including avascular necrosis, union, and degenerative change (osteoarthritis)
Funding and conflict of interest statements	Explicit statement that there was no outside funding or grants for the study Statement confirming that the authors or their immediate families had not received financial payments or other benefits from any commercial entity in relation to the article nor had they made any commitments or agreements to provide such benefits
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Randomization was accomplished with use of a random numbers list generated by software and kept by the operating room nurse."
Allocation concealment (selection bias)	Unclear risk	"Before the surgery, the circulating nurse reviewed the random‐numbers list. Patients who had been assigned an odd number were subsequently treated with a locking nail, and those who had been assigned an even number were managed with a locking plate."
Blinding (performance bias and detection bias) Functional outcomes, pain, clinical outcomes, complications	High risk	No mention of blinding. However: "All of the follow‐up physical examinations and radiographic evaluations were done by the same independent observer."
Blinding (performance bias and detection bias) Death, reoperation	Unclear risk	No mention of blinding; lack of blinding less likely to affect these outcomes
Incomplete outcome data (attrition bias) Functional outcomes, pain, clinical outcomes, complications	Low risk	Participant flow diagram provided; similar and modest losses in each group
Incomplete outcome data (attrition bias) Death, reoperation	Low risk	Participant flow diagram provided; similar and modest losses in each group: data reported
Selective reporting (reporting bias)	Unclear risk	Insufficient information to judge this
Balance in baseline characteristics?	Unclear risk	No indication of any major baseline imbalance in 51 participants followed up at 3 years but no data for 6 participants lost to follow‐up
Free from performance bias?	Low risk	All surgical procedures performed by senior surgeon and comparable rehabilitation. Although general anaesthesia used only for the plate group, this was considered unlikely to affect the findings