Hip and knee prostheses, a model to increase the success of interventions
Walk the day after surgery. It happens to 93% of patients undergoing hip and knee replacement surgery at the Campus Bio-Medico University Hospital Foundation. A “quite exceptional” figure for professionals, constantly growing – the success rate was around 80% about ten years ago – but which only partially explains the paradigm shift that has taken place in recent years. Made possible by a mix of innovation in the operating room, yes, but also in the management of patients who need to resort to a prosthesis due to arthrosis or fractures. To the point that, a few months after the operation – from three to six months – one even “forgets” about the replaced joint. Telling us about it is Rocco Papalia director of the Orthopedics and Traumatology Unit of the Roman center (among the “Hospitals of excellence” for thehip, knee and shoulder orthopedics), and full professor at the Campus Bio Medico University.
The design of a prosthesis
“Many patients renounce it out of fear of surgery and in this way not only risk worsening the existing damage to the affected joints, but also to those upstream and downstream – says Papalia – But if correctly indicated, hip prostheses and knee can significantly improve patients’ quality of life, with exceptional recoveries.” The exceptional recoveries Papalia talks about are the result of increasingly precise and increasingly personalized planning of the operation, which begins in the pre-operative phase. “Initially we collect data on the joint thanks to a three-dimensional CT scan, this data is sent to the USA and analysed. In response we receive information on the measurements of the prostheses and their positioning, and on the rotation of the femur and tibia for the stability of the joint”. These indications are then compared with the patient’s anatomy, revised in light of the surgeon’s experience and guide the operation in the operating room. Where, for a few years, a robot has arrived alongside doctors, or rather a robotic arm (like Mako) capable of making a difference.
In the operating room
“Robotics – continues Papalia – has increased the precision of surgeons, especially in the management of soft tissues, such as ligaments and joint capsules linked to the ‘sensitive’ part of the joint, both in terms of proprioception and sensitivity to pain. By reducing surgical gestures on the joint and making more precise cuts, we are able to greatly reduce errors. This, essentially, translates into early recovery thanks to the reduction of post-operative pain, foreign body sensation and increased joint stability and control.”
Monitoring of patients in the post-operative phase
Yet, automated intraoperative planning and management efforts are not enough to ensure the success of a prosthesis operation. Patient management in the post-operative phase is also fundamental, starting from the monitoring of joint function: “We have put together a data tracking model that combines the use of wearable systems – to understand, objectively, how the joint works, for example how much it flexes and how it moves – and a series of indices (score) clinical tests, such as those relating to how long the patient can stand, how far he can walk”. All this enormous amount of data – from the pre-operative to the post-operative phase – is finally combined within databases in which, also thanks to Artificial Intelligence, predictive models are developed: “In this way we can understand if a particular type of intervention, with positioning of the prosthesis in a certain way, has higher success rates than others”, explains Papalia.
Pain management
An essential part of the post-operative phase is also pain management, now multimodal: “We talk about drugs, physiotherapy and cryotherapy, and support with internal medicine specialists to follow any other problems of the patient, such as cardiovascular pathologies and diabetes, or specialists capable to manage any psychological aspects – concludes the expert – And it is essential to understand that pain management cannot be the same for all patients, but must be personalized”.
