This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
To assess the effects of computer assisted reconstruction surgery versus conventional operating techniques for ACL or PCL deficient knees in adults.

We will test these effects according to the following specific subgroups:
1. System used for CAS (e.g. per-operative use of X-rays, pre-operative use of radiology (CT, MRI, X-rays), per-operative landmarks or bone morphing).
2. Type of ligament reconstruction: ACL or PCL, or both.