Date: 201808
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Weather elements / visibility: Rain; Turbulence
Aircraft: B767 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class E ZZZ
ATC / advisory: Center ZZZ
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Fatigue; Time Pressure; Situational Awareness
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Flight Deck / Cabin / Aircraft Event Illness / Injury; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: General Physical Injury / Incapacitation
Contributing factors: Weather
Primary problem: Weather

Narrative: First leg of this trip; delayed departure for ZZZ due to maintenance; aircraft swap; and lightning closing the ramp. Wake up [extremely early] this morning. Both FOs (First Officers) and I seemed surprisingly alert for preflight and departure; but we were all undoubtedly somewhat affected by fatigue by the last hour of this leg; due to the extreme delay on the flight over; and the extremely early wake up today. [Dispatch] noted FCST TSTMS ZZZ AND VCTY AT ETA. TAF included -SHRA with PROB30 -TSRA at arrival time. In my brief to Purser I noted the forecast; and the possibility of descent turbulence; and the likely need to finish service and sit; sooner than normal prior to landing.ZZZ ATIS auto updates indicated 1 mile with heavy rain at destination. We received a reroute from ARTCC; to proceed from ZZZ1 to ZZZ2. Approaching ZZZ1 from the east at FL340; I could see some weather on the distant horizon. I asked [Operations Control] via ACARS message; how the descent rides were into ZZZ. Reply was; PIREPS INDICATE LGT TURBC BETWEEN FL100 and FL060. I remained leery; and made a PA more than one hour before our FMC eta for destination; prior to initial descent; letting the passengers know that it was their last opportunity to move about the cabin if necessary prior to landing. I also told the FAs (Flight Attendants) to finish their final service early; and to expect possible turbulence in descent. Just prior to top of initial descent; and at the request of one FA who called the IRO (International Relief Officer) on the interphone; we turned on the seat belt sign. As we approached ZZZ1; wx radar showed a good sized cell; and on our route; it was all green with the gain at AUTO; but with a fairly solid yellow spot to the south of our route. We asked ARTCC how the rides were through it; after they had cleared us to descend to 16;000. The arrival says to expect 10 east of ZZZ2 at 16;000; and we were descending appropriately. ARTCC said light chop or turb; with moderate rain. The monitoring FO; returned from rest break 3; and the IRO and I took quick final lav breaks. The rain in the cell was light; and there was almost no turbulence initially. The rain intensity increased; but turbulence remained light. Toward the back end of the cell; descending between 18;000 and 16;000; we hit a sudden patch of what felt to us in the flight deck; was moderate turbulence. IRO made the Flight attendants be seated immediately PA. Monitoring FO made PIREP to ARTCC. [Operations Control] was notified via text of the moderate turbulence in descent approaching ZZZ2 between 18;000 and 16;000. We soon received an interphone call that an FA X had injured her foot; and that it was possibly broken. We cleared the weather; the ride became smooth; and we made the flight attendants check in PA. The IRO called the cabin again; and suggested someone apply ice to the injured foot. We were then apprised that FA Y stated that his neck had 'cracked;' and he could move it; but thought he might have whiplash. [Operations Control] was apprised of both injuries. Both injuries occurred in the aft galley. Paramedics and an in-flight supervisor were requested from [Operations Control] and ZZZ ops. IRO called cabin again; and was told the two injured FAs were stabilized. There appeared to be no traffic ahead of us on our arrival; and we did not declare a medical emergency. We landed normally at ZZZ; taxied to gate; where paramedics were standing by. The passengers were asked to remain seated; so the paramedics could board and care for the injured. The IRO immediately went aft; as the other FO and I completed the PARKING checklist. The purser and I remained at the top of the jetway for a number of minutes; until both injured FAs agreed to be transported to the hospital. The Purser; FA X (injured foot) and I; exchanged phone numbers. FA X texted me from the hospital; to let me know that she and FA Y; were both being evaluated and treated.


Second narrative: [Report narrative contained no additional information.]


Synopsis: B767 flight crew reported that flight attendants were injured due to turbulence during descent.