Guillaume Grenier, principal investigator is no longer working at the lab. The lab is now closed.

Bone fractures in traumatic brain-injured and spinal cord-injured patients often heal faster than in other patients. However, such patients are also occasionally prone to bone formation in soft tissues such as muscle. This process is called heterotopic ossification and tends to occur around joints. Patients with heterotopic ossification often suffer from complications such nerve compression, ankylosis, chronic pain, osteoporosis, and infections. Loss of movement can also interfere with function and the quality of life of patients already experiencing difficulties associated with their trauma. Positioning, transfers, and hygiene become difficult and even impossible, which worsens the loss of autonomy.

Previous research has suggested that an osteoinductive factor (which has the capacity to induce the formation of bone) may be released into the bloodstream following a head or spinal cord injury. The investigators laboratory has shown that a growth factor called BMP-9, when injected into a damaged mouse muscle, has the ability to cause strong ossification in damaged muscle. The investigators would like to find out whether the levels of BMP-9 and/or its receptor (which is called ALK1) increase after traumatic brain and spinal cord injuries that occur at the same time as serious orthopaedic traumas.

The main goal of the investigators study is thus to determine whether BMP-9 levels increase in the serum of trauma patients.

Inclusion Criteria:

• cranial trauma with Glasgow =< 8
• spinal trauma with ASIA A, B, C
• high-velocity fracture of femur, tibia, pelvis

Exclusion Criteria:

• brain dead
• pathological fractures (cancer, osteoporosis)
• blood transfusion received
• pregnancy

Patients arriving at the emergency room at the CHUS that present pathologies associated with the different cohorts described and responding to inclusion criteria.