Jinan, China --- Four cases of robot-assisted total knee arthroplasty (TKA), one of the scientific clinical projects of the Joints and Sports Medicine Department of Qilu Hospital of Shandong University, have been successfully completed recently with Honghu Orthopedic Surgical Robot (Honghu) independently developed by MicroPort NaviBot (Suzhou) Co., Ltd., a subsidiary of Shanghai MicroPort MedBot (Group) Co., Ltd. Qilu Hospital of Shandong University, ranked 19^th in the list of the top 100 hospitals of China in 2020, is also the only hospital of Shandong Province that has entered the top 20 of China. It has provided high-quality medical resources to patients in and around Shandong province. Honghu has a powerful 3D pre-operative planning function, which can perform 3D segmentation and reconstruction of joints based on preoperative CT images of patients and provide patients with the operative plan for personalized prosthesis implantation. Honghu is provided with the Chinese-developed robotic arm, which can resect bones through precise operation. It is unnecessary to open the femoral canal during the surgery. The patient suffered less bleeding and less trauma and can restore the force line of lower limbs.

The patients are respectively: (1) a 65-year-old female, who began to suffer from pain in her right knee joint a year ago and felt worse after weight-bearing or exercise. Conservative treatments such as self-administration of drugs made no obvious improvement, and the pain has worsened in the recent month and seriously affected her life. When admitted in hospital, she was diagnosed as having osteoarthritis in her right knee joint. (2) a 59-year-old female, who began to suffer from pain in both knee joints 4 years ago and felt worse after the left knee bore weight or exercised. The pain has worsened in the recent 4 years and seriously affected her life. When admitted in hospital, she was diagnosed as having osteoarthritis in her left knee joint. (3) A 61-year-old female, who developed pain in her left knee joint three years ago and was diagnosed as osteoarthritis of knee joint. She took oral painkillers, and the effect was acceptable. Later, the pain gradually worsened, and she was admitted in hospital and diagnosed as having developed osteoarthritis of left knee joint. (4) A 66-year-old female, who developed pain in both knee joints 10 years ago and was diagnosed as osteoarthritis of knee joints. She took oral painkillers, but the effect was not good enough. 1 year ago, the symptoms worsened. When admitted in hospital, she was diagnosed as having osteoarthritis in both left knee joints.

Before surgery, the doctors performed 3D CT reconstruction of knee joints for patients respectively through Honghu. It provides a friendly experience of human-computer interaction (HCI), making it easier for operators to make personalized surgical solutions based on the patient's 3D bone model. Honghu HCI Platform guided the robotic arm registration and bone registration nimbly during the surgery, the robotic arms accurately moved to the pre-planned position, assisted in the osteotomy of femur and tibia. Compatible with MicroPort^®Orthopedics medial-pivot knee system, the whole operation was completed smoothly and efficiently.

Postoperative measurement shows that the actual osteotomy is completely consistent with the planned value. The patient recovered fast after the operation, and the full-length radiograph of the lower limb showed that the force line had been accurately recovered, which proved the precise characteristics of Honghu.

The surgery has been completed successfully with Honghu and the whole operation was smooth and efficient. The humanized operation interface of Honghu not only respects doctors' traditional operation habits, but also shortens the learning curve of doctors. Compared with the traditional surgery, Honghu can perform 3D segmentation and reconstruction of the patient's joints in 3D based on CT images and achieve more accurate placement of prosthesis. Personalized adjustment may be conducted during the operation according to the patient's soft tissue condition to realize the gap balance. It is a higher level of construction for the diagnosis and treatment of joint arthroplasty.