Hynek Krušina was a member of the Lichtenburg family, which in turn was a branch of the powerful Ronov dynasty.
Čeněk probably persuaded Hynek to participate in the Bohemian Diet of 1415, where he protested against the condemnation of Jan Hus at the Council of Constance.
Hynek and his brothers Alexander (who died c. 1422) and Jan inherited his possessions of Opočno, Kumburk Castle and Albrechtice.
Hynek would not accept the loss of Albrechtice and a military conflict broke out, which was decided in 1414 in favour of the Queen.
Probably as a result of this conflict, Hynek found himself in financial difficulties and was forced to sell Opočno, which he had intended to give to Jan when the latter came of age.
In 1420 at Wrocław, Hynek and his brother Jan and other Bohemian nobles openly defied Emperor Sigismund.
Later that year, at Mount Oreb in Třebechovice pod Orebem near Hradec Králové, he founded the Orebites, a federation of East Bohemian towns which was led by the priest Ambrož Hradecký and pursued egalitarian goals.
After Albert was elected as King of Bohemia, Hynek was allowed to bear the royal sword at the coronation ceremony on 29 June 1438 the St. Vitus Cathedral in Prague and took part as seneschal in the subsequent celebrations.
In October 1438, Albert had to leave Prague to avert a Polish invasion in Silesia and afterwards travelled to Hungary to repel the Turks.
On 6 September 1440, he purchased the liens over the estate of Kladsko, the Duchy of Münsterberg, the city of Ząbkowice Śląskie and some East Bohemian possessions, from Anna of Koldice, the widow of Půta III of Častolovice.
Her East Bohemian possessions included Nové Hrady, Rychmberk Castle, Potštejn, Albrechtice, Choceň, Hummel and Častolovice.
In August 1441, Hynek joined the Landfrýd, a regional alliance of nobles and cities to keep the peace, at its meeting in Čáslav.
At this meeting, he probably came into contact with the robber baron Jan Kolda of Žampach, who held Rychmberk Castle and the Lordship of Hummel illegally.
On 15 and 16 July 1443, Duke William of Opava and Münsterberg, Bishop Konrad of Wrocław and their allies besieged Chałupki Castle and took it.
On 16 October 1452, Parliament adopted a motion, which was then brought to Vienna by a high-level delegation, which included Hynek.
On 9 December 1455 Hynek's widow Anna endowed a benefice that hymns may be sung at Krušina's grave every Tuesday.
In an obituary published by the monastery at Kamieniec Ząbkowicki, Hynek was described as a loyal patron (fidelis fautor monasterii).
A few weeks after Hynek's death, his son William — probably due to a preliminary contract concluded by Hynek — sold the possessions that had belonged to the Častolovice family, including the estate of Hummel, the lien of Kladsko and the city of Ząbkowice Śląskie to George of Poděbrady, who would later be elected King of Bohemia and who already owned the adjacent estate of Náchod.