Narrative:

During cruise climb to 38;000 feet and passing 36;000 feet flight encountered unexpected wake turbulence. Climbing at .77 mach with a pitch attitude of approximately 7 degrees nose up and autopilot engaged; aircraft suddenly shuddered and went into a right bank of approximately 25 degrees. I immediately disconnected the autopilot and rolled wings level with a pitch attitude on the horizon. As the aircraft was climbing we did not lose altitude but rate of climb was reduced to near zero. The climb was then continued to 38;000 feet. Bank limits were not exceeded and the aircraft was not over stressed. I called the purser and was informed that everything was fine in the cabin. Subsequently I learned that a flight attendant in the rear of the cabin had bumped her shin on the service cart during the wake turbulence encounter. She informed me that she thought she was fine and had not been injured. I have included potential injury as part of the event report as a precaution in case something manifests itself in the future. Dispatch was notified via ACARS and a phone patch was set up with the [chief pilot] for the purpose of verbally debriefing the event and a potential crew member injury. The nearest traffic to our position at the time of the wake encounter was an airbus (A320) approximately 8 miles ahead and 2;000 feet above. The flight continued uneventfully. I continued to monitor the flight attendant's condition throughout the flight; and on the return flight. She continued to feel that she had not sustained any injury.

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Original NASA ASRS Text

Title: B737NG flight crew reported a Flight Attendant was slightly injured during a wake turbulence encounter at FL360.

Narrative: During cruise climb to 38;000 feet and passing 36;000 feet flight encountered unexpected wake turbulence. Climbing at .77 Mach with a pitch attitude of approximately 7 degrees nose up and autopilot engaged; aircraft suddenly shuddered and went into a right bank of approximately 25 degrees. I immediately disconnected the autopilot and rolled wings level with a pitch attitude on the horizon. As the aircraft was climbing we did not lose altitude but rate of climb was reduced to near zero. The climb was then continued to 38;000 feet. Bank limits were not exceeded and the aircraft was not over stressed. I called the Purser and was informed that everything was fine in the cabin. Subsequently I learned that a Flight Attendant in the rear of the cabin had bumped her shin on the service cart during the wake turbulence encounter. She informed me that she thought she was fine and had not been injured. I have included potential injury as part of the event report as a precaution in case something manifests itself in the future. Dispatch was notified via ACARS and a phone patch was set up with the [Chief Pilot] for the purpose of verbally debriefing the event and a potential crew member injury. The nearest traffic to our position at the time of the wake encounter was an Airbus (A320) approximately 8 miles ahead and 2;000 feet above. The flight continued uneventfully. I continued to monitor the Flight Attendant's condition throughout the flight; and on the return flight. She continued to feel that she had not sustained any injury.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.