Stryker (NYSE:SYK) said today that a pair of studies of its Mako robot-assisted knee replacement technology showed better patient outcomes and reduced episode-of-care (EOC) costs.

A prospective, consecutive series, single-surgeon study compared 40 patients undergoing manual total knee arthroplasty (TKA) with 40 patients undergoing Mako robotic-arm-assisted TKA. Patients who had the robot-assisted procedures had less post-operative pain, a decreased need for opiate analgesics, a 26% reduction in length of hospital stay and less need for in-patient physical therapy according to the study, published in Bone and Joint Journal.

A longitudinal, retrospective analysis of claims data from the Centers for Medicare and Medicaid Services (CMS)  concluded that Mako TKA patients had overall lower average 90-day EOC costs to Medicare compared with those who underwent manual TKA. Mako patients had lower facility costs, shorter lengths of stay, decreased readmissions and discharges to less expensive facilities than those who underwent manual TKA, the study showed.

Another prospective cohort study comparing macroscopic bone and soft-tissue injury between Mako TKA and manual TKA indicated reduced bone and soft tissue damage in the Mako patient group. Published in the Journal of Arthroplasty, that study included 30 consecutive manual TKAs followed by 30 consecutive Mako TKA procedures, all performed by a single surgeon.

Mako uses a CT-based 3D modeling of bone anatomy to create a patient-specific surgical plan and is equipped with haptic guidance for surgeons.

“Mako has been changing the game across the entire joint replacement service line for years and we’re excited to continue leading the charge in this space,” said Stuart Simpson, president of Stryker’s joint replacement division, in a prepared statement. “Mako is transforming the way hip and knee replacements are performed and we are proud to be at the forefront of the robotics movement in orthopeedics.”

Stryker announced the study outcomes at the American Academy of Orthopaedic Surgery (AAOS) meeting in Las Vegas.