Hi laxmi64

my doubt being a spinal injury patient why he did not have spasticity in limbs?
Spasticity is quite variable in spinal cord injury and patients can have very little or a lot. Anyway you say he has spasticity in his adductors. Does he have other signs of upper motor syndrome:
  • deep tendon reflexes?
  • Babiniski? Hoffmans?

It might be helpful to completely map out the presence of upper motor neurone symptoms vs lower motor neurone symptoms and signs
What about sensory changes?

The fact that he lost consciousness does mean he incurred a traumatic brain injury. So then it is possible some of the symptoms could be from that - less likely given the evidence of a syrinx on Wikipedia reference-linkMRI but you can't rule that out. you could see if there are other motor signs not indicative of spinal cord injury such as a positive finger-to-nose test, cranial nerve tests etc.

the relative sparing of the upper limbs with more lower motor symptoms (no spasticity) and the greater involvement of the lower limbs may all be consistent with the syringomyelia and the intact bladder and bowel control would suggest an incomplete spinal cord lesion.

The syringomyelia is a concern. Is this stable or does it need surgically managing? What has been the nature of recovery since the injury - getting worse?, stayng the same? getting better? Is someone monitoring this in case the syrnx needs draining?

clawing of fingers seen bilaterally. elbow flexor tightness more in left than in right.
If this is not due spasticity and he has been allowed to develop such severe contractures this really is a bad case of medical mismanagement. Why did he miss out on physio? Is his surgical team following him up?