An institutional study on accuracy of freehand cervical C1 C2 screws placement by knock and drill technique in craniovertebral anomalous bony anatomy: An evaluation of more than 60... oleh Sudhir Bisan Sasapardhi, Pawan Kumar Verma, Arun Kumar Srivastava, Kuntal Kanti Das, Ashutosh Kumar, Priyadarshi Dikshit, Ved Prakash Maurya, Kamlesh Singh Bhaisora, Anant Mehrotra, Awadhesh Kumar Jaiswal, Prabhaker Mishra, Sanjay Behari, Raj Kumar, Harshit Mishra, Kalyani Shahare