Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Flight Crew Last 90 Days 106
Flight Deck / Cabin / Aircraft Event Illness / Injury; Inflight Event / Encounter Wake Vortex Encounter
Flight Crew Took Evasive Action; General Physical Injury / Incapacitation
Environment - Non Weather Related; Procedure
Passing FL350; smooth air; had a moderate jolt from wake turbulence from another aircraft.  Airplane rolled about 25 degrees right then back to the left.  Autopilot was on.  First Officer turned autopilot off to expedite climb toward FL370. Event lasted 2-3 seconds.  Flight Attendant in the back reported that she fell and hit her upper arm on the seat.  She said she was OK; but would ice it when she got a chance.  She continued her duties to ZZZ1.  No medical response required or asked for. Dispatch notified and maintenance report sent. Nearest aircraft about 20 miles away.
On climb out the ride was smooth. Climbing through approximately FL350 up to FL370 several rolling moments occurred both left and right. The autopilot was immediately disengaged and an increased climb rate was initiated. The ride immediately smoothed out and a normal level off occurred. A Flight Attendant in the rear of the aircraft notified us that she made contact with the plane. No other weather events occurred. After discussions with the Captain she noted she was okay to continue the flight. Reports were filed according to the FOM.  The nearest known aircraft was approximately 20 miles ahead and slightly higher.
B767 flight crew reported a minor injury to a Flight Attendant occurred during a wake turbulence event at FL350.