Femoroacetabuläres Impingement: Häufige Ursache von zur Arthrose führenden Hüftbeschwerden

Zusammenfassung: Während die Ursache der Gelenkschädigung bei der Hüftdysplasie auf eine überhöhte axiale Belastung der Gelenkpfanne klar zurückgeführt werden kann, ist die exakte Ursache der idiopathischen Koxarthrose bis heute nicht geklärt. Basierend auf der Entwicklung einer chirurgischen Technik zur gefahrlosen chirurgischen Luxation der Hüfte und der damit verbundenen Möglichkeit der intraoperativen Gelenkbeurteilung, fanden wir eine bewegungsinduzierte Schädigung, die peripher am Acetabulumrand beginnt und nach zentral fortschreitet. Dieses sog. "femoroacetabuläre Impingement" (FAI), welches durch eine vermehrte acetabuläre Überdachung und/oder fehlende Sphärizität des Femurkopfes zu einem Anschlagen bzw. Einpressen des Femurkopfes in die Gelenkpfanne führt, verursacht eine Schädigung des Labrum und/oder des Gelenkknorpels. Häufig kommt bei den bereits in der 2. und 3. Lebensdekade symptomatisch werdenden Patienten (Leistenschmerzen, reduzierte Innenrotation) eine vermehrte sportliche Aktivität hinzu. Basierend darauf, ob die acetabuläre oder femorale Pathologie dominiert, werden zwei verschiedene Typen des FAI, das Pincer- (Beißzangen-) und das Cam- (Nockenwellen-)FAI unterschieden. Neben diesen ossären Alterationen tragen auch eine supraphysiologische Beweglichkeit sowie eine Überbeanspruchung zum FAI bei. Das Impingement-Konzept hat zu einer Reihe neuer, mehrheitlich intrakapsulärer Chirurgieansätze geführ

Hip morphology influences the pattern of damage to the acetabular cartilage. Femoroacetabular impingement as a cause of early osteoarthritis of the hip

Recently, femoroacetabular impingement has been recognised as a cause of early osteoarthritis. There are two mechanisms of impingement: 1) cam impingement caused by a non-spherical head and 2) pincer impingement caused by excessive acetabular cover. We hypothesised that both mechanisms result in different patterns of articular damage. Of 302 analysed hips only 26 had an isolated cam and 16 an isolated pincer impingement. Cam impingement caused damage to the anterosuperior acetabular cartilage with separation between the labrum and cartilage. During flexion, the cartilage was sheared off the bone by the non-spherical femoral head while the labrum remained untouched. In pincer impingement, the cartilage damage was located circumferentially and included only a narrow strip. During movement the labrum is crushed between the acetabular rim and the femoral neck causing degeneration and ossification. Both cam and pincer impingement lead to osteoarthritis of the hip. Labral damage indicates ongoing impingement and rarely occurs alone. © 2005 British Editorial Society of Bone and Joint Surgery

Femoroazetabuläres Impingement als Auslöser der Koxarthrose

Zusammenfassung: Das femoroazetabuläre Impingement (FAI) ist häufig, die geschätzte Prävalenz liegt bei 10-15%. Unsere bisher 10-jährige Erfahrung bestätigt das FAI als eine wesentliche, wenn auch nicht einzige Ursache der Koxarthrose. Isolierte azetabuläre oder femorale Fehlformen sind selten, obwohl bei Frauen die azetabuläre und bei Männern die femorale Pathomorphologie dominiert. Normalbefunde im Standardröntgen schließen ein FAI nicht aus. Symptome treten umso früher auf, je größer die Deformität und je intensiver hohe Bewegungsanforderungen gestellt werden. Die überwiegende Mehrzahl der Patienten ist <40Jahre alt. Im Unterschied zum Impingement bei der Hüftendoprothetik ist das natürliche Gelenk mechanisch viel satter gefasst, was kein Ausweichen im Sinne der Subluxation oder gar Luxation ermöglicht. Entsprechend hoch sind die Impingementkräfte, die beim häufigen, nicht-sphärischen Hüftkopf (femorale Fehlform, Cam-FAI) mit schnellen Bewegungen der Beugung und Innenrotation eine von außen nach innen verlaufende Ablösung des Pfannenknorpels hervorrufen. Der Knorpel des sphärischen Hüftanteils bleibt zunächst intakt, ein Bild, das mit der klassischen Entstehungstheorie der Koxarthrose nicht in Einklang zu bringen ist. Erst wenn der Hüftkopf in die Zone des geschädigten Pfannenknorpels migriert, beeinflussen auch vertikal verlaufende Kräfte den Arthroseverlauf. Risse zwischen Labrum und Knorpel, wie sie im MRT beobachtet werden, sind nicht als Abrisse des Labrum vom Knorpel, sondern Abrisse des Knorpels vom Labrum zu verstehen. Bei der azetabulären Über-Überdachung (azetabuläre Fehlform, Pincer-FAI) ist das Labrum die erste Struktur, die geschädigt wird, der Knorpelschaden tritt sekundär auf. Die Behandlung des FAI bei Patienten <40Jahren erfolgt, wenn möglich, gelenkerhaltend. Ist die Knorpelschädigung ausgedehnt, ist bei gleichem Aufwand ein schlechteres Ergebnis der chirurgischen Therapie zu erwarten als bei geringem Schaden. Entsprechend wichtig ist die frühe Diagnosestellung, mit der neben der Einleitung der kausalen Therapie auch die beruflichen und sportlichen Weichen angepasst werden solle

The acetabular blood supply: implications for periacetabular osteotomies

As the popularity of juxta-acetabular osteotomies in adults increases, concern arises that such a procedure will potentially cause avascular necrosis of the acetabular fragment. In order to verify the remaining vascularization after a Bernese periacetabular osteotomy, an injection study with colored latex was performed. The vascularity of the outside of the periacetabular bone was studied in 16 hips after injection of colored latex into the abdominal aorta and the inside in four hips. To confirm the conclusions drawn from the anatomic study, a Bernese periacetabular osteotomy was performed in two additional hips after latex injection. This study demonstrated that through a modified Smith-Peterson approach and with execution of the osteotomies from the inside of the pelvis the acetabular fragment remains vascularized by the supra-acetabular and acetabular branches of the superior gluteal artery, the obturator artery and the inferior gluteal artery. Some uncertainty remains about how much correction is tolerated by the smaller blood vessel

Measurement properties of the German version of the IKDC subjective knee form (IKDC-SKF).

PURPOSE: To examine the measurement properties of the German International Knee Documentation Committee Subjective Knee Form (IKDC-SKF) in knee disorder patients. METHODS: Three hundred twelve consecutive patients undergoing surgery for anterior cruciate ligament, meniscus and/or cartilage injuries completed the IKDC-SKF, Lysholm Score, Tegner Activity Scale, and Short Form-12 Health Survey before and 6 months post-surgery. IKDC-SKF measurement properties were calculated and patients were also asked to rate the relevance/comprehensibility of the questionnaire items. RESULTS: Reliability was good with high Cronbach's alpha and intraclass correlation coefficients, and standard error of measurement values of 4.4 to 6.0. The smallest detectable change (SDC) ranged from 12.3 to 16.7 points. Validity was good with 90% of all hypotheses confirmed. Confirmatory factor analysis did not show adequate fitting indices within the model. Over half of the items were rated as essential, and all were well comprehended. The majority of hypotheses for responsiveness were confirmed. No floor and ceiling effects were observed. The area under the curve ranged from 0.82 to 0.89 and the minimal important difference was smaller than the SDC. CONCLUSIONS: The German IKDC-SKF is a reliable outcome measure with good hypotheses testing and responsiveness, but its MIC and structural/content validity need further analysis

Limitations of balloon sinuplasty in frontal sinus surgery

Balloon sinuplasty is a tool that is used to treat selected patients with paranasal sinus pathologies. No studies have investigated the aetiology of failed access to the frontal sinus. The aim of our study was to specify the intraoperative technical failure rate and to analyse the aetiology of the failed access to predict potential technical difficulties before surgery. We retrospectively analysed the charts of patients who underwent balloon sinuplasty from November 2007 to July 2010 at three different ENT-Centres. CT-analysis of the patients with failed access was performed. Of the 104 frontal sinuses, dilation of 12 (12%) sinuses failed. The anatomy of all failed cases revealed variations in the frontal recess (frontoethmoidal-cell, frontal-bulla-cell or agger-nasi-cell) or osteoneogenesis. In one patient, a lymphoma was overlooked during a balloon only procedure. The lymphoma was diagnosed 6months later with a biopsy during functional endoscopic sinus surgery. In complex anatomical situations of the frontal recess, balloon sinuplasty may be challenging or impossible. In these situations, it is essential to have knowledge of classical functional endoscopic sinus surgery of the frontal recess area. The drawbacks of not including a histopathologic exam should be considered in balloon only procedure

Hip muscle weakness in patients with symptomatic femoroacetabular impingement

SummaryObjectiveFemoroacetabular impingement (FAI) is a pathomechanical process, which may cause hip pain, disability and early development of hip osteoarthritis (OA) in young and active adults. Patients with FAI experience functional disability during dynamic weight-bearing activities, which could originate from weakness of the hip muscles. The objective of this study was to compare hip muscle strength between patients with symptomatic FAI and healthy controls. It was hypothesized that patients would present overall hip muscle weakness compared to controls.MethodsA total of 22 FAI patients and 22 controls matched for gender, age, and body mass participated in the study. We evaluated isometric maximal voluntary contraction (MVC) strength of all hip muscle groups using hand-held and isokinetic dynamometry, and electromyographic (EMG) activity of the rectus femoris (RF) and tensor fasciae latae (TFL) muscles during active flexion of the hip.ResultsFAI patients had significantly lower MVC strength than controls for hip adduction (28%), flexion (26%), external rotation (18%) and abduction (11%). TFL EMG activity was significantly lower in FAI patients compared with controls (P=0.048), while RF EMG activity did not differ significantly between the two groups (P=0.056).ConclusionsPatients with symptomatic FAI presented muscle weakness for all hip muscle groups, except for internal rotators and extensors. Based on EMG recordings, it was demonstrated that patients with symptomatic FAI have a reduced ability to activate TFL muscle during hip flexion. These findings provide orthopedic surgeons with objective information about the amount and specificity of hip muscle weakness in patients with FAI. Future research should investigate the relationship between hip muscle weakness, functional disability and overuse injury risks, as well as the effects of hip muscle strengthening on clinical outcomes in individuals with symptomatic FAI

Avascular femoral head necrosis in young gymnasts: a pursuit of aetiology and management.

AIMS Avascular femoral head necrosis in the context of gymnastics is a rare but serious complication, appearing similar to Perthes' disease but occurring later during adolescence. Based on 3D CT animations, we propose repetitive impact between the main supplying vessels on the posterolateral femoral neck and the posterior acetabular wall in hyperextension and external rotation as a possible cause of direct vascular damage, and subsequent femoral head necrosis in three adolescent female gymnasts we are reporting on. METHODS Outcome of hip-preserving head reduction osteotomy combined with periacetabular osteotomy was good in one and moderate in the other up to three years after surgery; based on the pronounced hip destruction, the third received initially a total hip arthroplasty. RESULTS The described pathology is quite devastating, and extensive joint preserving surgery (which has been shown successful in Perthes' cases) was less successful in this patient cohort. CONCLUSION Supraselective angiography may be helpful to improve pathomechanical understanding and surgical decision making.Cite this article: Bone Jt Open 2022;3(9):666-673

The 12-item Oxford Knee Score: cross-cultural adaptation into German and assessment of its psychometric properties in patients with osteoarthritis of the knee

SummaryObjectiveTo cross-culturally adapt and validate the Oxford Knee Score (OKS) for use in German-speaking patients with osteoarthritis of the knee.MethodsAfter the cross-cultural adaptation (OKS-D), the following metric properties of the questionnaire were assessed in 100 consecutive patients (mean age 66.5 years, 61 women) undergoing total knee replacement: feasibility (percentage of fully completed questionnaires), reliability (Intraclass Correlation Coefficients [ICC] and Bland and Altman's limits of agreement), and construct validity (correlation with the Western Ontario and McMaster Universities Index [WOMAC], Knee Society Score [KSS], Activities of Daily Living Scale [ADLS], and Short Form 12 [SF-12]), floor and ceiling effects, and internal consistency (Cronbach's Alpha, CA).ResultsWe received 91.9% fully completed questionnaires. Reliability of the OKS-D was excellent (ICC 0.91). Bland and Altman's limits of agreement revealed no significant bias (−0.2) and a random error of 6.2. Correlation coefficients with the other questionnaires ranged from −0.22 (SF-12 Mental Component Scale [MCS]) to −0.77 (ADLS). We observed no floor or ceiling effects. The CA was 0.83.ConclusionsThe German version of the OKS is a reliable and valid measure for the self-assessment of pain and function in German-speaking patients with osteoarthritis of the knee