CLINICAL FACTORS Soft tissue handling and minimizing blood loss are keys to enhancing recoveries and ensuring timely discharges.

What separates the same-day joints programs where you'd feel comfortable sending your mom from the facilities where you'd rather refer your ex? To find out, we spoke to 3 joint replacement specialists who shared their thoughts on difference-making innovations that leading surgeons are using to bring same-day discharge to total hip and knee patients.

1. Multimodal mastery
Scott Ball, MD, an associate professor of orthopedic surgery at UC San Diego Health in San Diego, Calif., performs total hips, total knees and partial knees. He doesn't try to push the outpatient envelope when treating joint replacement patients — he cares more about positive outcomes than he does about where the procedures are performed — but acknowledges several developments have made same-day total joints much more feasible than in years past. Multimodal pain management tops his list.

Dr. Ball says the amount of post-op pain that patients experience is almost always the determining factor between overnight stays and same-day discharges, and improvements in anesthetic techniques and pain management protocols have been the biggest game-changers for knee replacement patients over the last 15 years.

Stephen Kayiaros, MD, an orthopedic surgeon at University Orthopaedic Associates in Somerset, N.J., operates through a mini-incision on the knee and doesn't violate the quadriceps tendon to lessen the post-op pain of his knee replacement patients. He also uses the muscle-sparing anterior approach to the hip, so there are no post-op concerns about range-of-motion restrictions. "That's made it a bit easier to transition hips to the outpatient setting when it comes to controlling post-op pain," he says.

Dr. Kayiaros's knee replacement patients receive adductor canal nerve blocks. The block affects sensation, not motor function, at the joint so patients can participate in physical therapy soon after surgery. They also receive a tibial nerve sensory block, which helps control pain in the knee's posterior capsule and prevents patients from experiencing post-op drop foot, which could limit their abilities to complete prescribed physician therapy. Dr. Kayiaros also sends patients home with a pain pump that delivers analgesics to the operative site for 3 to 4 days after surgery to control pain in the immediate post-op period, which is when patients are typically in the most discomfort.

TO BE EXACT Robotics is the perfect tool for partial knee replacements, according to Steven Harwin, MD, FACS.

Dr. Ball touts the increased use of local anesthetic injection cocktails at the surgical site to numb the pain of surgery. "The injections are helping to get patients up and moving soon after surgery, because they're simply not hurting as much," he says.

Joint replacement patients are surprisingly comfortable for the first 36 hours post-op, says Dr. Ball. When inflammation sets in and the perioperative cocktail of pain medicines wears off, however, the pain returns. "We've solved controlling pain on post-op days 1 and 2," says Dr. Ball. "Over the next 10 years, I think we'll solve days 2 through 21. After that period, inflammation typically subsides and patients are in minor discomfort, not acute pain."

2. Robotic-assisted surgery
Steven Harwin, MD, FACS, chief of advanced technology of total hip and knee arthroplasty at Mount Sinai Hospital in New York, N.Y., has performed more than 12,000 joint replacements in his career. Despite that level of experience, he stopped performing partial knee replacements, because, in his mind, he couldn't complete the required intricate cuts well enough by hand. He's now back at it, thanks to robotic technology, which he says has significantly improved partial knee replacement outcomes.

"The use of robotics is becoming a game-changer, and will continue to develop as one, in terms of improving implant placement and surgeon technique," says Dr. Harwin.

The robotic arm Dr. Harwin uses eliminates the need for standard instrumentation. He used to place a cutting block on the femur or tibia, secure it with pins and make the necessary cuts for placing the implant. The block would invariably shift slightly during surgery, so Dr. Harwin would have to reposition it before re-cutting. The second cuts wasted valuable procedure time and weren't always as accurate as they could have been.

Robotics eliminates those issues. Dr. Harwin's platform develops an operative plan based on a pre-op CT scan of the patient's anatomy. Once the robot arm is registered to anatomical landmarks, it knows where bones are in space and makes perfect cuts for exact placement of the implant. Haptic feedback prevents him from moving outside of predetermined boundaries of the optimal operative approach. "Risk of inadvertent cuts to surrounding tissue, ligaments, tendons, nerves or blood vessels is also virtually eliminated," says Dr. Harwin.

He believes the technology allows for better positioning and sizing of implants and likely lets surgeons perform proper gap and ligament balancing better than they could do manually. "But we can't yet say the technology has the ability to improve outcomes," says Dr. Harwin. "That will be determined over the long term."

Dr. Kayiaros employs handheld computer navigation. The technology helps him optimize the alignment and position of the implant, which ultimately leads to improved long-term function of the prosthesis and better longevity. The single-use device, which contains an accelerometer and gyroscope and attaches to conventional instrumentation, lets Dr. Kayiaros navigate in real time exactly where to make bone cuts in the femur and tibia, so the implant is aligned exactly with the mechanical axis of the leg.

The subtleties of knee replacement involve how well soft tissue is balanced, and the robot doesn't impact that aspect of care, says Dr. Ball. He views computer-assisted navigation and robotic platforms as simply just another tool surgeons can use to place an implant, at least for now. He believes the technology will reach its full clinical potential in the future when it's paired with smarter implant technology. That brings us to the third surgeon-endorsed game-changing development.

3. High-performance hardware
Implant materials have improved significantly in recent years, says Dr. Kayiaros. "The polyethylene bearings used in hips and knees are manufactured so that the wear is essentially negligible," he explains. "That's been a huge advancement."

The knee implant Dr. Kayiaros uses is a "high-flex design," so the geometry of the prosthesis is designed to maximize the joint's post-op range of motion. He also points out that most manufacturers produce a wide range of implant sizes that can be tailored to the patient's anatomy during surgery.

Dr. Harwin says cementless total knee replacement systems provide biological bonds, which produce better stability and rotation, so post-op joint function more closely resembles the body's natural movements. He also says that advancements in hip socket prostheses are more evolutionary than revolutionary, but notes that dual-mobility designs provide a better range of motion with added stability in hip replacement patients. OSM