I suspect something is pinching his urethra, possibly downstream from the prostate. Maybe swelling from the injury. If he complains about it, he should see a doctor. I suppose scar tissue might form to interfere with the flow of things. How is his urine flow? Does he go more often? Is the flow slower than before the injury?
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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