Medium Transport
Air Traffic Control Developmental
Workload; Situational Awareness
ATC Issue All Types; Flight Deck / Cabin / Aircraft Event Illness / Injury; Inflight Event / Encounter Weather / Turbulence
General Physical Injury / Incapacitation
Weather; Company Policy
At the start of the shift; convective weather was rapidly forming moving slowly north and east near where the incident occurred. Cells were intensifying rapidly due to daytime heating and resulted in many pop-up cells that were causing deviations within the sector. At the time of the incident; we were running both departures from the ZZZ area and arrivals into the ZZZ area through the same 20 to 25 mile gap where weather was least impacting the aircraft. All overflights were also transiting through the same area; adding to the complexity.Aircraft X; entered my airspace at 21;000 feet and was assigned a heading from the previous sector to avoid a cell that was building in his vicinity. I issued a routing which at the time was south and west of the precipitation that was depicted on my scope and that I knew was clear based on pilot reports that I had solicited. Weather was issued to the aircraft as well as left and right deviations as necessary. He was issued a descent to 19;000 feet; pointed out to another sector; and was handed off with no issues in my airspace. Upon entering the next Controller's airspace; the pilot reported that he had hit severe turbulence; gashed his head open and was bleeding. The pilot advised ATC and landed safely.   The complexity of having to essentially 'play chicken' with arrivals and departures added immensely to the complexity of the sector. Earlier in the session; I mentioned to the TMU (Traffic Management Unit) Supervisor who came into the area that we should consider closing the arrival; but that happened too late. About 10 to 15 minutes prior to this event occurring; we finally closed the arrival down but allowed three aircraft to continue on the arrival; which jammed up the already small lane that I had to work with.This weather had been building throughout the day; and the fact that it took so long to move planes away from the affected arrival is a constant issue that we have in this facility. This sector is one of the smallest in the facility; and arguably one of the most complex; so adding in weather and unusual operations increases complexity immensely. We generally know when the weather is going to be there and how it's going to affect our operations; so steps should be preemptively taken to reroute these aircraft into better weather and not have to deal with the potential for having these incidents occur.
A Center Controller reported a pilot reported severe turbulence that caused an injury.