Aspects of present disclosures involve systems, methods, and apparatus for a bone mounted robotic-assisted orthopedic surgery system for precise implant position, soft tissue balancing, and guidance of tools during a surgical procedure, particularly partial or total knee replacement procedure. The system features a bone-mounted robotic arm with an end-effector for precise positioning of a surgical tool, positioning of implants, and balancing of soft tissues. The reconfigurable robotic system requires minimal training by surgeons, is intuitive to use similar to conventional instrumented surgery, and has a small footprint. The system works with existing, conventional instruments, patient-specific instruments, sensor-assisted systems, and computer-assisted systems and does not require increased surgical time and safely provides the enhanced precision achievable by robotic-assisted systems and computer-assisted technologies.