Wrightington, Wigan and Leigh NHS Trust has been fined after it plead guilty to health and safety breaches following an incident last year.
The accident occurred on May 5th 2006 and involved a patient on the Taylor Ward Neurological Rehabilitation ward at Leigh Infirmary.
On May 7th 2005 the patient climbed out of the first floor window in his room and fell to the ground, a distance of 4.4m, fracturing his ankle when he landed.
The Trust was fined £8,000 and ordered to pay £4,141 costs at a hearing.
Tom Merry, the health and safety inspector who investigated the incident commented: "The case highlights the importance of an effective management system for maintaining buildings in a safe condition."
It is essential that window restrictors are properly fitted and are working as desired, he added.
The Royal National Orthopaedic Hospital NHS Trust was recently fined £15,000 following an accident in which a worker was badly scolded by steam.