[Experience in establishing a certified endoprosthesis center]

[Quality criteria in arthroplasty]

The discipline of orthopedics and trauma surgery strives for constant improvement of the quality of results in arthroplasty; however, in order to enable targeted alterations to the establish standard operating procedures, dedicated documentation of the current quality of results is necessary. This can be achieved by so-called external quality assurance, evaluation of routine data of healthcare providers, analysis of clinical studies and the consultation of registry data. To achieve further improvement of the quality of results, legislature has been passed setting requirements for minimum quantities and by the specialist society (German Society for Orthopedics and Orthopedic Surgery, DGOOC) the adherence to certain process and structural guidelines within the framework of the certification system EndoCert®. A valid score for risk adjustment for assessment of the level of difficulty of orthopedic surgical interventions is so far lacking. As a future direction, the application of risk stratification concerning patient-specific anatomy should be developed. Through the combination of dedicated certification systems, the recording and evaluation of external inpatient quality assurance data, further quality assurance through routinely collected data and the development of adequate minimum quantity regulations, sustainable improvement of the quality of results can be achieved.

[Patient safety during endoprosthetic training : Does the training of surgeons in primary hip arthroplasty at certified endoprosthesis centres lead to increased complications?]

Hintergrund

Ziel der Studie war die Untersuchung, ob sich das perioperative Outcome und operationsspezifische Prozessgrößen bei Patienten mit Hüftgelenksersatz signifikant verschlechtern, wenn die Operation durch einen unerfahrenen Operateur, assistiert durch einen erfahrenen Operateur, im Kontext eines zertifizierten Endoprothesenzentrums durchgeführt wird.

Material und Methoden

Es wurden 1480 Patienten eingeschlossen, die zwischen 2013 und 2016 bei primärer Koxarthrose mit einer primären zementfreien Hüfttotalendoprothese (HTEP) versorgt wurden. Die relevanten Daten wurden retrospektiv aus dem Krankenhausinformationssystem, dem Entlassungsbrief und aus dem EndoCert-Bogen dokumentiert. Die Operateure wurden nach ihrer Qualifikation in erfahrene (Senior, > 50 HTEP pro Jahr) und unerfahrene Operateure (Junior, < 50 HTEP pro Jahr) unterteilt. Anschließend erfolgte der Vergleich der erhobenen Daten anhand dieser Unterteilung.

Resultate

Es zeigte sich bei unerfahrenen Operateuren eine signifikante Verlängerung der Operationsdauer um 20,7 min (Senior 62,6 ± 20,4 min; Junior 83,3 ± 19,5 min; p ≤ 0,001), der Krankenhausverweildauer um 0,25 Tage (Senior 8,8 ± 0,9 d; Junior 9,0 ± 0,9 d; p ≤ 0,001) und eine Erhöhung der Transfusionshäufigkeit von Erythrozytenkonzentraten (Senior 0,6 ± 1,1 Stk.; Junior 0,9 ± 1,4 Stk.; p ≤ 0,001). Dagegen zeigte sich kein Unterschied bei perioperativen Komplikationen (p = 0,682) und beim perioperativen Blutverlust (Senior 1,3 ± 0,5 l; Junior 1,3 ± 0,5 l; p = 0,097). Zwischen Operationsdauer und Blutverlust bestand allerdings eine positive Korrelation (Senior r = 0,183; Junior r = 0,214; jeweils p ≤ 0,01).

Schlussfolgerung

Die Ausbildung von unerfahrenen Operateuren an einem zertifizierten Endoprothesenzentrum führt bei Assistenz durch erfahrene Operateure nicht zur Reduktion der Patientensicherheit mit vermehrten Komplikationen. Aufgrund der Operationszeitverlängerung kommt es allerdings zu einer Mehrbelastung der Kliniken im Wettbewerb mit nichtausbildenden Kliniken, die nicht im DRG-System abgebildet ist.

[Discrepancy between radiographic and true cup position after total hip arthroplasty : Are we interpreting our radiographic quality indicators correctly? Video article]

BACKGROUND

After total hip arthroplasty (THA), objective postoperative quality control is done via X‑rays by as component position assessment. The cup position is defined by its version and inclination. However, there is a discrepancy between radiographically measured and true (anatomic) cup position, which may lead to misinterpretation.

METHODS

To visualize the discrepancy between true and radiographically measured cup position, in this video, a cup holder was used to set the angular cup version and inclination. Hereby, the cup position (anteversion and inclination) can be characterized in its radiographic and anatomic definition in greater detail. The viewer of this video should receive an impression as to when radiographically measured cup angles must be considered with caution.

RESULTS

In a simultaneous X‑ray and image sequence, this video shows decreased radiographic inclination measurement with increasing anterior rotation of the cup exceeding 20° of anteversion, yet with unchanged true inclination on the cup holder. Isolated consideration of the radiographic angles of anteversion and inclination may cause misinterpretation of true cup position. In pectoral illustration we show that variations in cup version and inclination may remain undetected when considering isolated the radiographic cup parameters.

CONCLUSION

True cup position in its anatomical definition can be calculated from the radiographically measured position. For this purpose, both cup parameters (radiographic anteversion and radiographic inclination) have to be taken into account.

[Complications and costs in primary knee replacement surgery in an endoprosthetics centre : Influence of state of training]

BACKGROUND

This work examines the hypothesis that in endoprosthesis implantation there are differences between experienced primary and senior caregivers (S-Op) and less experienced follow-up assistants (T-Op) with respect to process-relevant parameters. The main hypothesis is that compared to S‑Op, T‑Op cause significantly longer surgery times and thus additional operating theatre costs. As sub-hypotheses, differences in various perioperative (p-o) parameters between T‑Op and S‑Op were examined.

MATERIALS AND METHODS

The status of the operator (senior and/or senior main operator [S-Op]) and/or postoperative CRP, perioperative blood loss, the amount of transfused erythrocyte concentrates, patient age, gender, ASA risk classification (American Society of Anesthesiologists), duration of surgery and blood transfusion, duration of inpatient stay, as well as the rates of early revision surgery and complications were recorded. A comparison of patients who had been operated by an S‑Op and those who had been operated by a T‑Op was made for all parameters.

RESULTS

Significant differences were found with respect to the duration of surgery, the duration of the hospital stay, and CRP on the third p‑o day. The T‑Op required an average of 11 min more than the S‑Op. CRP was significantly higher in the T‑Op group only on the third p‑o day, by 18 mg/l. In contrast, in the T‑Op group, a blood loss of 181 ml was lower than in the S‑Op group. This corresponded to a reduction of 0.26 transfused erythrocyte concentrates. There were no significant differences in complication rates between S‑Op and T‑Op.

DISCUSSION

In the setting of a certified endoprosthetics centre, the comparison of T‑Op with S‑Op showed that the use of the former with at a non-increased complication rate led to a significant extension of the operating time. This leads to additional training costs in the amount of an estimated 3% of the current DRG remuneration. These additional costs are not represented adequately in the current remuneration system.

[Does the certification according to EndoCert lead to a better quality of treatment?]

BACKGROUND

Certification according to EndoCert in the field of arthroplasty in Germany aims at standardization of treatment and with this optimization of its quality. However, huge capital investment and efforts are necessary. There are currently more than 400 certified centres in Germany. Our Department of Orthopaedics at a German medical school was certified in the pilot phase. The aim of this study was to analyse whether there was a difference in the quality in the year after the certification. A second aim was to analyse whether the defined quality criteria are adequate for a university hospital.

MATERIALS AND METHODS

The quality criteria as defined by EndoCert were analysed in the year before (2011) and after certification (2012). The observed complications were noted for 1 year postoperatively. The clinical outcome was analysed with Western Ontario and McMaster University Osteoarthritis Index Score (WOMAC) 1 year postoperatively.

RESULTS

There was no difference concerning the criteria analysed, including the clinical outcome in the year before and that after certification. In both years, nearly all criteria could be reached except the operation time and the infection rate in hip and knee revision surgery.

CONCLUSION

Certification did not lead to a measurable change of the quality of care. Nearly all criteria, except the infection rate in revision arthroplasty (required: less than 3% at 1 year postop.) and the operation duration could be fulfilled. This rate as well as the operation duration should be revised. Certification according to EndoCert is an important tool to prove quality care, however big efforts and capital are needed. The criteria should be constantly revised and reduced, as these resources should not be missed in patient care.

Postoperative Increased Loading Leads to an Alteration in the Radiological Mechanical Axis After Total Knee Arthroplasty

BACKGROUND

Standing long-leg radiographs allow assessment of the mechanical axis in the frontal plane before and after total knee arthroplasty (TKA). An alteration in loading, and hence in the forces acting on the knee joint, occurs postoperatively. We therefore postulated that the mechanical axis measured in the long-leg standing radiograph would change within the first year after TKA.

METHODS

Standing long-leg radiographs of 156 patients were performed 7 days, 3 months, and 12 months after TKA with determination of mechanical axis of the lower limb.

RESULTS

Seven days after surgery, the mechanical axis amounted 0.8° ± 1.7° valgus. Three months after the operation, at 1.3° ± 1.3° varus, it was significantly different (P < .001) from the primary measurement. No further alteration in the mechanical axis occurred during the first year after TKA. This difference was even more pronounced (P < .001) in patients with a postoperative lack of complete extension. Seven days after surgery, they had a valgus axis deviation of 1.6° ± 1.6°; after 3 months, the measurement amounted 1.2° ± 1.3° varus.

CONCLUSION

Measured by a standing long-leg radiograph, the frontal mechanical axis after TKA changes over time. The predictive power of a standing long-leg radiograph in the first week after surgery is limited because limb loading is altered because of pain and is therefore nonphysiological. The actual mechanical axis resulting after TKA can only be assessed in a standing long-leg radiograph at physiological loading.