Date: 201705
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Large Transport; Low Wing; 2 Turbojet Eng
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Tower ZZZ
Second aircraft: Large Transport; Low Wing; 2 Turbojet Eng
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Confusion; Distraction; Situational Awareness
Second reporter function: Dispatcher
Anomaly: ATC Issue All Types; Conflict Ground Conflict; Critical; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Taxiway
Detector: Person Flight Crew
When detected: Taxi
Result: Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Gate; Flight Crew Took Evasive Action; General Physical Injury / Incapacitation
Contributing factors: Procedure; Human Factors
Primary problem: Procedure

Narrative: Our original push back from ZZZ gate X was delayed due to a minor maintenance issue in the passenger cabin. We pushed from the gate (tail south) seventeen minutes after our originally scheduled departure time. After push back and engine start; we were cleared to taxi to Runway XXR. Before starting to taxi; I cleared the left side of the aircraft; and the FO cleared the right side of the aircraft. We verbalized 'Clear left' and 'Clear right;' respectively. As I made the left turn out of the gate area; my attention was initially focused on fuel truck on the right side of the aircraft. The truck seemed to be properly parked; but required a sharp left turn out of the gate area to clear it. Once I was clear of the truck; I turned my head back to the left and suddenly noticed an imminent collision with Aircraft Y; which was taxiing northbound on Taxiway A. I stopped my aircraft immediately; and Aircraft Y continued to taxi past us. While an immediate stop was absolutely necessary to avoid a collision; the brakes did grab somewhat harder than I had anticipated; and we came to a stop more abruptly than I had intended. Unfortunately; two of my flight attendants fell during the stop and sustained injuries. Despite my aircraft being partially past the ramp boundary hold line and encroaching on Taxiway A; I told the ground controller that we needed to hold our position while we assessed the nature of the injuries. We quickly ascertained that the injuries were severe enough that both flight attendants would not be able to continue their duties and that a return to the gate would be necessary. While the FO coordinated the return to the gate with the ramp controller; I queried the ground controller; stating that we had been cleared to taxi. I asked her if we were supposed to have given way to Aircraft Y. She responded with; 'Negative.' The ramp controller initially cleared us to return to gate Y; but then changed the gate to gate Z. Ground control cleared us to Gate Z and stated that all traffic would hold for us. During the return to the gate we requested to be met by medical personnel. After our arrival at the gate there was a short delay before the medical personnel arrived. However; they eventually did arrive and tended to the injured flight attendants. One Flight attendant sustained apparent injuries to her back. She was able to walk off the aircraft; down the jet bridge stairs; and to the ambulance waiting on the ramp. The other Flight attendant sustained apparent injuries to one of her arms and was also escorted off the aircraft by the medical personnel. Supervisors were also there to meet us at the gate. They assisted us in caring for the injured flight attendants and in finding replacement flight attendants.While we waited at the gate for the replacements; we called the ground controller and asked if he knew the call sign of Aircraft Y. It was a different ground controller than we had originally spoken with; but he said he would push the request up to his supervisor. We were later informed that the other aircraft was an inbound arrival. Since Aircraft Y was an inbound and we were an outbound; we were obviously on different ground control frequencies. It is unclear to me whether he was instructed to give way to us but failed to do so; or if there was a coordination problem between the inbound and outbound ground controllers. I only know that I was cleared to taxi and never instructed to give way to Aircraft Y. During our wait for replacement flight attendants; I called Dispatch on the phone; and informed [dispatch] of our return to the gate with flight attendant injuries. I told [dispatch] that we were planning on topping off our fuel and continuing the flight with the current release (RLS 02). We were also met in the cockpit by a Representative. He told us that he had reviewed the video tapes of the incident; which he described as 'dramatic.' He stated that we only narrowly avoided a collision with the other aircraft. Eventually; two replacement flight attendants arrived at the aircraft; and we left the gate 1 hour and 46 minutes after our originally scheduled departure time.


Second narrative: Aircraft X was a departure and controlled by departure ground (121.XX); Aircraft Y was an arrival and controlled by arrival ground (121.YY). Aircraft Y continued taxi and Aircraft X then requested to return to the blocks; due to possible flight attendant injuries.


Synopsis: Pilots; Dispatcher; and Tower Controller reported of a ground conflict that resulted in injuries to flight attendants.