Knee surgeries with large differences in quality between clinics

26.10.2023 16:10

During knee replacement surgery for joint wear and tear, there are large differences in the frequency of complications such as revision surgery and other complications that may occur after the procedure. The publication of current results from the WIdO's “Quality Assurance with Routine Data” (QSR) procedure shows that complication rates in the quarter of clinics with the best results are less than half as high as in the quarter of clinics that perform worst in the evaluation. The results of the individual clinics are available in the AOK health navigator.

The current evaluation shows that the overall complication rate for knee joint replacements due to joint wear was a maximum of 2.6 percent in the quarter of clinics with the best treatment results, while it was at least 6.1 percent in the quarter of clinics with the worst quality results. The average value for all cases was 4.1 percent (Figure). The results of the analysis are based on around 137,000 knee joint replacement operations by AOK insured people between 2019 and 2021, which were followed up for up to one year. As of today, they are available for each individual clinic in the AOK health navigator. Here the AOK also offers current results for a total of 13 treatment occasions, which are evaluated using the QSR procedure. In order to ensure a fair comparison of hospitals, different patient characteristics such as age, gender or previous illnesses are taken into account as part of the risk adjustment.

Revision operations are necessary in almost 3 percent of all cases

Particularly clear differences can be seen in the evaluation of revision operations within one year, which occurred in an average of 2.9 percent of all cases: while in the quarter of clinics with the best results, artificial knee joints had to be operated on again in a maximum of 1.7 percent of cases , in the quarter with the worst results, at least 4.3 percent of patients were affected by these unplanned follow-up operations. Surgical complications following the actual operation, such as infections, injuries to the blood vessels, tearing of the surgical wound or loosening of the artificial joint, affected a maximum of 1.1 percent of those insured by the AOK in the “top clinics”, while in the quarter of the worst clinics were at least 3.5 percent. The average value here was 2.3 percent. There were also differences in deaths related to the operation, which are very rare overall.

AOK calls for the minimum quantity of 50 operations to be increased

Since the knee joint is one of the most stressed joints in the body, wear and tear of the cartilage layer (osteoarthritis) often occurs with increasing age. The result is often severe pain that can only be relieved through surgery. The worn joint is replaced by a so-called endoprosthesis. Artificial knee joints can – depending on their level of stress – remain functional for a very long period of time.

According to studies, there is a connection between the routine of the operating clinic and the treatment result when it comes to knee joint replacement. Therefore, since 2015, a minimum quantity of 50 total knee joint replacements per year and hospital location has been approved by the Federal Joint Committee. “An additional evaluation by the WIdO shows that clinics with high numbers of cases – with exceptions – usually perform better in the QSR process than hospitals with relatively few cases per year,” emphasizes AOK board member Jens Martin Hoyer. The AOK welcomes the fact that Federal Health Minister Karl Lauterbach wants to advance the quality-oriented concentration of hospital services with the planned hospital reform. “This concentration is urgently needed in the interests of patient safety and quality of care,” said Hoyer. From the AOK's point of view, the quality transparency of the QSR procedure, which is related to certain interventions and operations and is understandable to laypeople, could also be a model for corresponding information in the planned "transparency directory", which is to be introduced next year with the Hospital Transparency Act.

QSR information on a total of 13 operations and treatments

Information on treatment quality from the QSR procedure is not only available for the implantation of artificial knee joints, but also for knee prosthesis replacements and eleven other treatments. These are the implantation of an artificial hip joint for osteoarthritis, surgery after a fracture of the femur near the hip joint, hip prosthesis replacement, gallbladder removal for gallstones, appendectomy, tonsillectomy, inguinal hernia surgery, surgery for benign prostate enlargement and prostate removal for prostate cancer, therapeutic cardiac catheter (PCI) for patients without a heart attack and catheter-supported Aortic valve implantation (TAVI). Current evaluation results in layman's terms are now also available for these treatments, which can often be planned, in the AOK health navigator. They are displayed when users search for information about one of these treatments in the navigator. The quality transparency of the QSR procedure related to certain interventions and operations can also be a model for corresponding information in the planned “transparency directory”, which is to be introduced next year with the Hospital Transparency Act.