Z‐TUpx NCT04917536.

Methods	Randomised controlled trial
Participants	80 (target) participants, aged between 10 and 70 years, with a humeral shaft fracture or proximal humeral fracture (Neer 2, 3 or 4); assigned for anterograde nailing
Interventions	1. Rotator cuff split approach: nail inserted through the rotator cuff split, between the supraspinatus tendon and the long part of the biceps 2. Rotator cuff approach: nail inserted through the supraspinatus tendon, which is closed at the end of the surgery
Outcomes	Follow‐up: 1 year QuickDASH, Constant score, Simple Shoulder Test, pain (VAS), complications, duration of surgery, duration of sick leave, duration of rehabilitation, radiological assessment of bone healing, haemoglobin levels
Notes	Found in November 2021 top‐up search Ongoing trial. Recruiting. Trial dates: June 2021 to June 2024