Bearing tray locking mechanism

An adjustable implant comprising:

• an attachment device implantable into a bone of a patient;
• a tray configured to be attached to the attachment device, the tray including:
• receptacles circumferentially spaced around a peripheral region of the tray, the receptacles formed in the tray such that the receptacles extend through the tray, and
• a bearing configured to be coupled to the tray, the bearing including:
• attachment mechanisms circumferentially spaced around a peripheral portion of the bearing and engageable with the receptacles of the tray to couple the bearing to the tray, each one of the attachment mechanisms engageable with each one of the receptacles, in the alternative, such that a rotational position of the bearing relative to the tray can be adjusted by engaging the attachment mechanisms with different ones of the receptacles in the tray.