Julian Mehl

Evidence-based concepts for prevention of knee and ACL injuries. 2017 guidelines of the ligament committee of the German Knee Society (DKG)

IntroductionKnee injuries and especially anterior cruciate ligament (ACL) tears are frequent in athletes. Therefore, primary and secondary prevention of sports-related lower limb injuries is an ongoing topic of interest. The aim of present study was to establish guidelines for the prevention of knee and ACL injuries on the basis of evidence-based concepts represented in current literature.MethodsA comprehensive literature review regarding prevention programs for knee and ACL injuries was conducted.ResultsSeveral modifiable and non-modifiable risk factors for knee injuries in athletes have been reported in literature. Referring to the ACL, specific injury mechanisms have been identified and are well understood. In particular, it has been demonstrated that dynamic valgus is one of the most important modifiable risk factors. Simple tests like the drop jump test have shown their efficacy in screening and detecting athletes at risk. There is only few evidence for the preventive effect on knee and ACL injuries by single exercises. However, in order to prevent or correct endangering movement patterns including dynamic valgus, several complex prevention programs have been developed in the past. These prevention programs are included in standard warm-up exercises and are focusing on muscle strength, balance, and proprioception, as well as running and flexibility. It is reported that these training programs can reduce the incidence of knee injuries by up to 27% and ACL injuries by up to 51%.ConclusionsScreening, identification, and correction of endangering movement patterns like the dynamic valgus are the first crucial steps in order to prevent knee and ACL injuries in athletes. Furthermore, jumping, running and flexibility exercises as well as balance and strength training are proven to reduce the incidence of these injuries and should, therefore, be integrated into the regular warm up program. Appropriate complete prevention programs are freely accessible via the Internet and should be adapted to the specific sport disciplines.

Smoking and obesity influence the risk of nonunion in lateral opening wedge, closing wedge and torsional distal femoral osteotomies

PurposeLateral distal femoral osteotomies (DFO) have recently been performed more frequently. In addition to realignment for varus and valgus deformity, the indication was extended with the introduction of torsional osteotomies in patellofemoral instability. The purpose of this study was to assess the general and technical risk factors for nonunion in lateral opening, closing and torsional DFO.MethodsA total of 150 lateral DFO [98 opening wedge (LOWDFO) and 52 closing wedge (LCWDFO)] were analyzed in regard to potential risk factors for nonunion until plate removal. Nonunion was defined as failure of osseous consolidation according to clinical and radiological evaluation.ResultsIn LOWDFO, the nonunion rate was 2%, in LCWDFO the rate was higher with 9.6%. Nicotine abuse (p = 0.009) and a higher body mass index (p = 0.003) were significant risk factors. Patient’s age and gender, the wedge height, hinge fractures, monoplanar versus biplanar osteotomy as well as additional torsional osteotomies were not significant in regard of nonunion.ConclusionsLateral DFO have a low rate of complications and nonunion. Smoking and obesity were significantly associated with the risk of nonunion. Hinge fractures, monoplanar technique or complete bone cuts of the opposite hinge in torsional osteotomies did not negatively influence the nonunion rate in DFO.Level of evidenceLevel IV.

Anatomische Refixation der akuten medialen Kniegelenkinstabilität

ZusammenfassungDie akute hochgradige mediale Instabilität erfordert insbesondere im Fall multiligamentärer Knieverletzungen eine operative Versorgung. Dabei bedingt die Risslokalisation die Versorgungsart. Eine direkte Ankerfixation trägt zu einem gesicherten Band-Knochen-Kontakt bei. Intraligamentäre Risse sollten genäht werden. Eine zusätzliche Sicherung der genähten Strukturen kann durch ein „internal brace“ erreicht werden.AbstractAcute high-grade medial instability requires surgical intervention, especially in the case of multiligamentous knee injuries. The localization of the tear determines the type of individualized treatment. Avulsions are treated by direct anchor fixation to achieve a stable ligament-bone contact and intraligamentous ruptures are secured with sutures. An internal brace provides additional stabilization of the sutured reconstruction.

Knorpeltherapie am Kniegelenk: der aktuelle Stand der Dinge

Knorpelschäden am Kniegelenk sind mit einer Einschränkung der Lebensqualität assoziiert und stellen einen Risikofaktor für eine arthrotische Gelenkdegeneration dar. Weil von fokalen Knorpelschäden besonders junge, aktive Patienten betroffen sind, wird der Behandlung solcher Läsionen eine große klinische wie auch sozio-ökonomische Relevanz beigemessen.

Sind Meniskusoperationen überflüssig

Die arthroskopische partielle Meniskektomie ist eine der am häufigsten indizierten und durchgeführten Eingriffe des Kniegelenks. Bei subjektiv zufriedenstellenden Ergebnissen und niedriger Komplikationsrate wurden Indikation und Therapie lange als unkritisch angesehen. Neuere prospektiv randomisierte Studien stellen jedoch die Wirksamkeit und damit die Sinnhaftigkeit infrage. Der vorliegende Beitrag bietet eine Analyse der Studienlage unter besonderer Berücksichtigung der Relevanz in Hinblick auf Indikationsstellung zur partiellen Meniskektomie im klinischen Alltag.

Knorpelschäden des patellofemoralen Gelenkabschnitts

ZusammenfassungHintergrundIsolierte Knorpelschäden des Patellofemoralgelenks führen häufig zu einer schmerzhaften Funktionseinschränkung des Kniegelenks und stellen einen Risikofaktor für eine fortschreitende Gelenkdegeneration dar. Trotz stetiger Weiterentwicklung der chirurgischen Techniken zur Knorpelregeneration, scheinen die postoperativen Ergebnisse gerade an der Patella im Vergleich zu anderen Lokalisationen ungünstiger. Dies könnte dadurch bedingt sein, dass mögliche Begleitpathologien bislang zu wenig berücksichtigt und in das Therapiekonzept einbezogen wurden.ErgebnisseDer operative Algorithmus für patellofemorale Knorpelschäden unterscheidet sich prinzipiell nicht von anderen Lokalisationen im Kniegelenk. Zu den am häufigsten verwendeten Techniken der regenerativen Knorpeltherapie gehören knochenmarkstimulierende Therapien (z. B. arthroskopische Mikrofrakturierung) und die autologe Chondrozytentransplantation für reine Knorpeldefekte sowie in selteneren Fällen die autologe osteochondrale Transplantation für osteochondrale Läsionen. Die Behandlung von Knorpelschäden an der Patella stellt zum Teil hohe chirurgische Ansprüche, sodass oft eine individuelle Technik in Abhängigkeit von Größe und Lokalisation des Defekts sowie von möglichen Begleiteingriffen gewählt werden muss.SchlussfolgerungenRetropatellare Knorpelschäden sind zu 90 % mit Begleitpathologien assoziiert, wie beispielsweise einer Trochleadysplasie, einem Patellahochstand oder anderen geometrischen Anomalien des Patellofemoralgelenks. Daher sind Kombinationseingriffe aus knorpelchirurgischen Verfahren und Korrekturen des patellofemoralen Alignments von großer Bedeutung. Neuere Studien zeigen, dass solche kombinatorischen Ansätze der isolierten Knorpeltherapie bezogen auf die klinischen Ergebnisse überlegen sind. Kombinatorische Ansätze erscheinen damit geeignet die im Vergleich zu anderen Lokalisationen ungünstigere Prognose zu verbessern.AbstractBackgroundLocal cartilage defects of the patellofemoral joint frequently cause a painful decrease in joint function and represent a relevant risk factor for development of degenerative osteoarthritis. Despite continuous improvements in surgical cartilage repair techniques, postoperative results seem to be less favourable for patellar cartilage defects than for other knee joint locations. One explanation for this finding might be that possible co-pathologies have so far not been adequately considered and incorporated into the treatment concept.ResultsThe surgical algorithm for patellofemoral cartilage defects does not fundamentally differ from that for other knee joint locations. Commonly used procedures for regenerative cartilage repair are bone marrow stimulating techniques (e. g. arthroscopic microfracturing) and autologous chondrocyte implantation (ACI) for pure cartilage defects. In rare cases, autologous osteochondral transfer (OCT) is used for osteochondral lesions. Since chondral lesions of the patella are surgically very demanding, an individual approach depending on defect size, location and possible cotreatments is often necessary.ConclusionIn 90 % of cases, cartilage defects of the patella are associated with co-pathologies such as trochlea dysplasia, patella alta or further geometrical anomalies. Therefore, combined surgical procedures incorporating cartilage repair and correction of patellofemoral malalignment are of major importance. Since recent studies have provided evidence that such combined approaches are superior to isolated cartilage repair in terms of postoperative outcome, such approaches might enable the unfavourable prognosis of patellar cartilage defects compared to other locations to be improved.