What does an MRI with a large posterior disc osteophyte complex that effaces the ventral CSF and flattens left hemi-cord diameter of 6mm mean?

Arthritis in neck. Due to osteo arthritis of facet joints of vertebral bodies and thinning and herniation of disc backwards, there can be compression of spinal cord. Its significance depends on the symptoms and signs on examination of patient. See a neurologist or neurosurgeon.