Hello. Thanks for asking from HCM.
I can understand your concern. Non removal of stitch can not cause mental disorder. However severity of his
head injury can cause
brain damage and thus mental disorder. As your uncle has been operated for head injury, it means most probably his injury was dangerous. If you can provide details of his injury in next question, it would be more helpful to predict about consequences of head injury.
Damage in dominant side of brain (mostly left side brain) involving frontal and
temporal lobe results into mental disorder like decrease in intelligence, memory deficits, behavioural problems, abusive behaviour, poor thinking process. If his CT brain is suggestive of above mentioned brain damage, then mental disorder can be explained.
For management, you have to consult neurosurgeon,
psychiatrist, occupational therapist and physiotherapist. The doctors will evaluate him, prescribe him physiotherapy/behavioural therapy/
occupational therapy. It will take 12 to 18 months for maximum recovery.
Hope it will help you. Take care. Thanks.