P. von Roth

Ceramic on ceramic arthroplasty of the hip: new materials confirm appropriate use in young patients

The leading indication for revision total hip arthroplasty (THA) remains aseptic loosening owing to wear. The younger, more active patients currently undergoing THA present unprecedented demands on the bearings. Ceramic-on-ceramic (CoC) bearings have consistently shown the lowest rates of wear. The recent advances, especially involving alumina/zirconia composite ceramic, have led to substantial improvements and good results in vitro. Alumina/zirconia composite ceramics are extremely hard, scratch resistant and biocompatible. They offer a low co-efficient of friction and superior lubrication and lower rates of wear compared with other bearings. The major disadvantage is the risk of fracture of the ceramic. The new composite ceramic has reduced the risk of fracture of the femoral head to 0.002%. The risk of fracture of the liner is slightly higher (0.02%). Assuming that the components are introduced without impingement, CoC bearings have major advantages over other bearings. Owing to the superior hardness, they produce less third body wear and are less vulnerable to intra-operative damage. The improved tribology means that CoC bearings are an excellent choice for young, active patients requiring THA.

Significant muscle damage after multiple revision total hip replacements through the direct lateral approach

Intact abductors of the hip play a crucial role in preventing limping and are known to be damaged through the direct lateral approach. The extent of trauma to the abductors after revision total hip replacement (THR) is unknown. The aim of this prospective study was to compare the pre- and post-operative status of the gluteus medius muscle after revision THR. We prospectively compared changes in the muscle and limping in 30 patients who were awaiting aseptic revision THR and 15 patients undergoing primary THR. The direct lateral approach as described by Hardinge was used for all patients. MRI scans of the gluteus medius and functional analyses were recorded pre-operatively and six months post-operatively. The overall mean fatty degeneration of the gluteus medius increased from 35.8% (1.1 to 98.8) pre-operatively to 41% (1.5 to 99.8) after multiple revision THRs (p = 0.03). There was a similar pattern after primary THR, but with considerably less muscle damage (p = 0.001), indicating progressive muscle damage. Despite an increased incidence of a positive Trendelenburg sign following revision surgery (p = 0.03) there was no relationship between the cumulative fatty degeneration in the gluteus medius and a positive Trendelenburg sign (p = 0.26). The changes associated with other surgical approaches to the hip warrant investigation.

Diffusion tensor imaging of skeletal muscle--correlation of fractional anisotropy to muscle power.

PURPOSE Recent DTI studies demonstrated the possibility of fiber geometry visualization in skeletal muscle. We tested for an association between muscle power and standard DTI parameters, e. g. fractional anisotropy. MATERIALS AND METHODS Maximal muscle power (Lmax) of the soleus muscle was determined in 11 healthy subjects. Subsequently DTI was performed and standard parameters (fractional anisotropy - FA, mean diffusivity - MD, parallel diffusivity - PD, radial diffusivity - RD) were extracted in an ROI of the soleus muscle. RESULTS We found a signficant association of Lmax with FA (neg. correlation: r = -0.85, p = 0.0015) and RD (pos. correlation r = 0.80, p = 0.047). There was no signficant association of MD or PD. CONCLUSION Maximum muscle power is an indirect measure of fiber type distribution. The correlation between muscle power and DTI parameters can be explained by differences in fiber diameter and differences in the intracellular microstructure of type-1 and type-2 fibers. DTI should be evaluated as a tool for non-invasive quantification of fiber type distribution in skeletal muscle.

Komplikationen nach minimal-invasiver Hüftendoprothetik

ZusammenfassungHintergrundZiel minimal-invasiver Zugänge in der Hüftendoprothetik ist die Verringerung des Operationstraumas ohne Einschränkungen der Exposition von Femur und Azetabulum zur Gewährleistung einer reproduzierbaren Implantation. Trotz zunehmend verbesserter Instrumentation ist die Etablierung dieses Vorgehens in der Lernphase mit dem Risiko einer erhöhten Komplikationsrate verbunden.Ziel der ArbeitDie vorliegende Arbeit stellt spezifische und unspezifische Komplikationen nach minimal-invasiver Implantation einer Hüfttotalendoprothese (HTEP) dar und beschreibt Hinweise zu deren Vermeidung.Material und MethodenEs handelt sich um ein retrospektives Studiendesign. Bei 152 Revisionsoperationen nach minimal-invasiver HTEP-Implantation wurden eine Nachuntersuchung und eine Fehleranalyse durchgeführt.ErgebnisseVon den Patienten der 152 Revisionsoperationen waren 87 weiblich und 65 männlich. Eine genderspezifische Komplikationshäufigkeit konnte nicht festgestellt werden. Die häufigste Indikation zur Wechseloperation wurde aufgrund rezidivierender Luxationen gestellt. Nach anterolateralem Zugang in Rückenlage ergab sich eine größere Häufigkeit von Frakturen des Trochanter major.DiskussionDie minimal-invasive Implantation führt nur bei korrekter Technik zu sehr guten Ergebnissen. Vom muskelschonenden Aspekt des minimal-invasiven Zugangs profitieren besonders junge Patienten. Dieses Patientenkollektiv hat ein hohes Risiko, einem Revisionseingriff unterzogen werden zu müssen.AbstractBackgroundThe goal of minimally invasive surgery in total hip arthroplasty (MIS-THA) is reduction of surgical trauma without any limitations regarding exposure of the femur and acetabulum to achieve reproducible results. Despite improved instrumentation the implementation of these techniques is associated with a risk of higher complication rates.AimThe article describes specific and unspecific complications of MIS-THA and gives hints and tips on how to avoid them.Material and methodsIn a retrospective study 152 THA revisions following MIS-THA were examined and an error analysis was performed.ResultsThe study of 152 MIS-THA revisions included 87 female and 65 male patients. A gender-specific incidence of complications could not be found. The most common indication for revision surgery was due to recurrent dislocation. An increased incidence of fractures of the greater trochanter was observed using the anterolateral approach with the patient in a supine position.DiscussionThe MIS-THA procedure contributes to excellent early rehabilitation when performed correctly. The muscle preserving aspect can be counted as an advantage particularly for young patients. This patient collective has a high risk to undergo revision surgery.BACKGROUND The goal of minimally invasive surgery in total hip arthroplasty (MIS-THA) is reduction of surgical trauma without any limitations regarding exposure of the femur and acetabulum to achieve reproducible results. Despite improved instrumentation the implementation of these techniques is associated with a risk of higher complication rates. AIM The article describes specific and unspecific complications of MIS-THA and gives hints and tips on how to avoid them. MATERIAL AND METHODS In a retrospective study 152 THA revisions following MIS-THA were examined and an error analysis was performed. RESULTS The study of 152 MIS-THA revisions included 87 female and 65 male patients. A gender-specific incidence of complications could not be found. The most common indication for revision surgery was due to recurrent dislocation. An increased incidence of fractures of the greater trochanter was observed using the anterolateral approach with the patient in a supine position. DISCUSSION The MIS-THA procedure contributes to excellent early rehabilitation when performed correctly. The muscle preserving aspect can be counted as an advantage particularly for young patients. This patient collective has a high risk to undergo revision surgery.

Periprothetische Frakturen nach Hüft- und Knietotalendoprothesenimplantation

ZusammenfassungPeriprothetische Frakturen nach Hüft- und Knietotalendoprothesenimplantation sind potenziell schwerwiegende Komplikationen. Um eine individuell optimale Versorgung dieser teils komplexen Frakturen zu gewährleisten, sind spezifische Einteilungssysteme als diagnostische und therapeutische Grundlage notwendig. Dieser Übersichtsartikel befasst sich mit den epidemiologischen Aspekten und Risikofaktoren, der Diagnostik sowie den Einteilungssystemen zur periprothetischen Frakturklassifikation nach Hüft- und Knietotalendoprothesenimplantationen. Ergänzend zu den in der klinischen Routine am häufigsten verwendeten lokalisationsbezogenen Klassifikationen wird mit dem Unified Classification System (UCS) ein neues Einteilungssystem mit Anwendbarkeit auf das gesamte Spektrum der periprothetischen Frakturen vorgestellt. Erste Studien zur Evaluation dieser neuen Klassifikation berichten über gute Ergebnisse und eine zuverlässige Anwendbarkeit.AbstractPeriprosthetic fractures following hip and knee arthroplasty are potentially severe complications. As a fundament in diagnostic and therapeutic procedures, specific classification systems are necessary to ensure an optimal individualized treatment of these sometimes complicated fractures. This review article summarizes the epidemiological aspects, risk factors and diagnostics of periprosthetic hip and knee fractures. The most frequently used location related fracture classifications systems are explained. In addition, the recently introduced unified classification system (UCS), which is applicable to any location of periprosthetic fractures, is described in detail. Initial studies have shown a reliable applicability of the UCS to periprosthetic hip and knee fractures.Periprosthetic fractures following hip and knee arthroplasty are potentially severe complications. As a fundament in diagnostic and therapeutic procedures, specific classification systems are necessary to ensure an optimal individualized treatment of these sometimes complicated fractures. This review article summarizes the epidemiological aspects, risk factors and diagnostics of periprosthetic hip and knee fractures. The most frequently used location related fracture classifications systems are explained. In addition, the recently introduced unified classification system (UCS), which is applicable to any location of periprosthetic fractures, is described in detail. Initial studies have shown a reliable applicability of the UCS to periprosthetic hip and knee fractures.

Erratum zu: Periprothetische Frakturen nach Hüft- und Knie-totalendoprothesenimplantation@@@Erratum to: Periprosthetic fractures following total hip and knee arthroplasty: Risikofaktoren, epidemiologische Aspekte, Diagnostik und Klassifikationssysteme@@@Risk factors, epidemiological aspects, diagnostics and classification systems

ZusammenfassungPeriprothetische Frakturen nach Hüft- und Knietotalendoprothesenimplantation sind potenziell schwerwiegende Komplikationen. Um eine individuell optimale Versorgung dieser teils komplexen Frakturen zu gewährleisten, sind spezifische Einteilungssysteme als diagnostische und therapeutische Grundlage notwendig. Dieser Übersichtsartikel befasst sich mit den epidemiologischen Aspekten und Risikofaktoren, der Diagnostik sowie den Einteilungssystemen zur periprothetischen Frakturklassifikation nach Hüft- und Knietotalendoprothesenimplantationen. Ergänzend zu den in der klinischen Routine am häufigsten verwendeten lokalisationsbezogenen Klassifikationen wird mit dem Unified Classification System (UCS) ein neues Einteilungssystem mit Anwendbarkeit auf das gesamte Spektrum der periprothetischen Frakturen vorgestellt. Erste Studien zur Evaluation dieser neuen Klassifikation berichten über gute Ergebnisse und eine zuverlässige Anwendbarkeit.AbstractPeriprosthetic fractures following hip and knee arthroplasty are potentially severe complications. As a fundament in diagnostic and therapeutic procedures, specific classification systems are necessary to ensure an optimal individualized treatment of these sometimes complicated fractures. This review article summarizes the epidemiological aspects, risk factors and diagnostics of periprosthetic hip and knee fractures. The most frequently used location related fracture classifications systems are explained. In addition, the recently introduced unified classification system (UCS), which is applicable to any location of periprosthetic fractures, is described in detail. Initial studies have shown a reliable applicability of the UCS to periprosthetic hip and knee fractures.Periprosthetic fractures following hip and knee arthroplasty are potentially severe complications. As a fundament in diagnostic and therapeutic procedures, specific classification systems are necessary to ensure an optimal individualized treatment of these sometimes complicated fractures. This review article summarizes the epidemiological aspects, risk factors and diagnostics of periprosthetic hip and knee fractures. The most frequently used location related fracture classifications systems are explained. In addition, the recently introduced unified classification system (UCS), which is applicable to any location of periprosthetic fractures, is described in detail. Initial studies have shown a reliable applicability of the UCS to periprosthetic hip and knee fractures.

Erratum zu: Periprothetische Frakturen nach Hüft- und Knie-totalendoprothesenimplantation

1. Bail HJ, Kleber C, Haas NP et al (2009) Verteilungsplanung von Verletzten beim MANV oder Katastrophenplan.Unfallchirurg112:870–877 2. BayrischesStaatsministeriumdes Inneren:Hinweise für das Anlegen von Krankenhaus Alarmund EinsatzplänenStand04/2006 3. De Boer LD, Dubouloz M (2000) Handbook of disastermedicine.VSP,Zeist, S239–252 4. Kirchhoff R (1984) Triage im Katastrophenfall. Primed-Fachbuch,Erlangen 5. Langwieler TE, Knoefel WT, Izbicki JR (2001) Das Pankreastrauma – Diagnostik und Therapie. Viszeralchirurgie36(5):328–330 6. Schauwecker HH, Schneppenheim U, Bubser HP (2003)Hospital organization for themanagement ofmasscasualties.NotfallRettungsmed6:596–602 7. Sefrin P,Weidringer LW,WeissW (2004) Sichtungskategorien und deren Dokumentation. Dtsch Arztebl100(31/32):A2058–A2058 8. SchmiedleM,SefrinP(2003)LimitierendeFaktoren der stationären Versorgung unter katastrophenmedizinischenBedingungen.Notarzt19:220–228 Unfallchirurg 2016 · 119:539 DOI 10.1007/s00113-016-0184-2 Online publiziert: 23. Mai 2016

Verletzungen und Rekonstruktion des Streckapparates nach Knie-TEP@@@Management of extensor mechanism injuries following total knee arthroplasty

Extensor mechanism injuries in total knee arthroplasty include disruption of the quadriceps tendon, disruption of the patellar tendon, and/or patellar fractures. While these injuries are rare, they are a devastating complication to manage. This review summarizes the anatomy of the extensor mechanism, risk factors for extensor mechanism injuries, and the prevalence and diagnosis of extensor mechanism injuries. In addition, this review outlines non-operative and operative management options. A new surgical approach for the reconstruction and augmentation of the extensor mechanism with the use of a synthetic mesh is described in detail. In multiple publications and in our own experience this newly developed technique shows promising results.ZusammenfassungDieser Übersichtsartikel beschreibt die funktionelle Anatomie, die Risikofaktoren, die Prävalenz, die Diagnostik von Verletzungen des Streckapparates in Gestalt von Rupturen der Quadrizeps- oder Patellasehne oder einer Patellafraktur sowie die verfügbaren konservativen und operativen Behandlungsmethoden. Detailliert wird ein neuer operativer Ansatz für die Rekonstruktion des Streckapparates durch Verwendung eines synthetischen Netzes dargestellt. Diese Technik zeigt gegenüber zuvor angewandten Verfahren in mehreren Publikationen und nach den eigenen Erfahrungen vielversprechende Ergebnisse.AbstractExtensor mechanism injuries in total knee arthroplasty include disruption of the quadriceps tendon, disruption of the patellar tendon, and/or patellar fractures. While these injuries are rare, they are a devastating complication to manage. This review summarizes the anatomy of the extensor mechanism, risk factors for extensor mechanism injuries, and the prevalence and diagnosis of extensor mechanism injuries. In addition, this review outlines non-operative and operative management options. A new surgical approach for the reconstruction and augmentation of the extensor mechanism with the use of a synthetic mesh is described in detail. In multiple publications and in our own experience this newly developed technique shows promising results.

Umgang mit der Beugekontraktur in der primären Knieendoprothetik

Flexion contracture is a common deformity of the arthritic knee. The present publication describes causes, clinical relevance and surgical technique in the presence of flexion contractures in total knee arthroplasty. Flexion contracture can be attributed to different causes. Basically it is a mismatch between flexion and extension gaps. Moderate and severe deformities have to be corrected by additional surgical interventions. In most cases soft tissue techniques with release of contracted structures, the removal of osteophytes and additional distal femoral bone resection are necessary. The goal of these interventions is to achieve full extension of the knee. During rehabilitation attention has to be paid to maintain it with intensive physical therapy. A remaining flexion contracture is associated with inferior functional outcome and persistent pain.

Verletzungen und Rekonstruktion des Streckapparates nach Knie-TEP

Extensor mechanism injuries in total knee arthroplasty include disruption of the quadriceps tendon, disruption of the patellar tendon, and/or patellar fractures. While these injuries are rare, they are a devastating complication to manage. This review summarizes the anatomy of the extensor mechanism, risk factors for extensor mechanism injuries, and the prevalence and diagnosis of extensor mechanism injuries. In addition, this review outlines non-operative and operative management options. A new surgical approach for the reconstruction and augmentation of the extensor mechanism with the use of a synthetic mesh is described in detail. In multiple publications and in our own experience this newly developed technique shows promising results.ZusammenfassungDieser Übersichtsartikel beschreibt die funktionelle Anatomie, die Risikofaktoren, die Prävalenz, die Diagnostik von Verletzungen des Streckapparates in Gestalt von Rupturen der Quadrizeps- oder Patellasehne oder einer Patellafraktur sowie die verfügbaren konservativen und operativen Behandlungsmethoden. Detailliert wird ein neuer operativer Ansatz für die Rekonstruktion des Streckapparates durch Verwendung eines synthetischen Netzes dargestellt. Diese Technik zeigt gegenüber zuvor angewandten Verfahren in mehreren Publikationen und nach den eigenen Erfahrungen vielversprechende Ergebnisse.AbstractExtensor mechanism injuries in total knee arthroplasty include disruption of the quadriceps tendon, disruption of the patellar tendon, and/or patellar fractures. While these injuries are rare, they are a devastating complication to manage. This review summarizes the anatomy of the extensor mechanism, risk factors for extensor mechanism injuries, and the prevalence and diagnosis of extensor mechanism injuries. In addition, this review outlines non-operative and operative management options. A new surgical approach for the reconstruction and augmentation of the extensor mechanism with the use of a synthetic mesh is described in detail. In multiple publications and in our own experience this newly developed technique shows promising results.