The learning curve of patient-specific unikondylar arthroplasty may be advantageous to off-the-shelf implants: A preliminary study.

INTRODUCTION: Introducing a new arthroplasty system into clinical routine is challenging and could have an effect on early results. Since UKA are known to have failure mechanisms related to technical factors, reliable results and easy adoption are ideal. The question remains whether there are differences in objective procedure parameters in the early learning curve of different UKA systems. METHODS: two different UKA implants (Biomet Oxford[BO] followed by Conformis iuni[CI]) were introduced consecutively into clinical routine. We retrospectively analyzed the first 20 cases of each implant for one arthroplasty surgeon regarding operating time, correction of the mechanical axis, learning curve parameters, and revision rate of implants for 1.5 years postoperatively. RESULTS: Operating time (BO:98.3 ± 26.3min, CI:83.85 ± 21.8min (p < 0.078)), and tourniquet time differed in favor of the CI implant (BO:97.5 ± 29.5min; CI:73.5 ± 33.2 min; p < 0.017)). Mechanical alignment was restored in boths (preop:BO:mean 2.9°varus, CI:2.7°varus, postop:BOmean1.3°varus, CI:1°varus), while one BO patient and two CI patients were overcorrected. Operating time decreased from the first five implants to implants 16-20 for CI (95.2 ± 18.5min to 69 ± 21.5min, p < 0.076) and BO (130.6 ± 27.6min to 78 ± 17.3min, p < 0.009). Within 18 months of follow-up, 2 BO and 1 CI implants were revised. CONCLUSION: The introduction of an UKA implant was associated with longer surgery in both implants. Procedure time seems to differ between implants, while a learning curve was observed regarding instrumentation. CI implants seem to be reliable and adaptable in a medium-volume practice. The early results of this retrospective single-surgeon study were in favor of the individualized implant. Certainly, further studies encompassing larger cohorts with various implants are needed.

Gait deviations in transverse plane after SCFE in dependence on the femoral offset.

Residual deformity of the femoral head after slipped capital femoral epiphysis (SCFE) may be accompanied by a loss of femoral offset and lead to femoro-acetabular impingement (FAI), especially during hip flexion. It is hypothesized that during phases of the gait cycle, when the hip is flexed, the offset-loss is compensated by an increased external rotation. The gait pattern of 36 patients suffering from SCFE, who were treated by pinning-in-situ, were compared to a control group of 40 healthy adults by an instrumented 3D-gait analysis. Total patient group was subdivided into 3 subgroups in dependence on the offset (offset groups (OG)) quantified by the angle α according to Nötzli: OG1: α-angle <55°, OG2: α-angle between 55 and 75°, OG3: α-angle >75°. Comparisons were made at 3 instants: initial foot contact (0% gait cycle (GC)), 40-60% GC and 90-100% GC. Patients showed an increased external hip rotation during all 3 periods of the GC with a tendency of increasing external rotation in association with offset-loss. Only during hip extension (40-60% GC) there was a weak correlation between angle α and hip rotation (r=-0.375, p=0.024). In conclusion, the offset-loss does not lead to a functional relevant impingement during walking which needs compensation strategies like increasing external rotation during periods of hip flexion.

Imaging modalities in patients with slipped capital femoral epiphysis.

BACKGROUND: Slipped capital femoral epiphysis (SCFE) is a frequent disorder of the adolescent hip, which may lead to avascular necrosis (AVN) of the femoral head, chondrolysis and early osteoarthritis due to the post-slip deformity of the proximal femur. To warrant the best possible outcome for the affected (and contralateral) hip, early diagnosis and proper treatment are needed. METHODS: A review of the literature was undertaken to identify today's role of available imaging modalities in the management of SCFE. SUMMARY: This review outlines the relevancy of different imaging modalities such as radiography, ultrasound, CT, MRI and bone scintigraphy in the treatment of SCFE patients. While standard radiography is the first-choice imaging modality for patients with suspected SCFE, ultrasound and advanced imaging modalities may aid in surgical planning, diagnosis of complications such as AVN and treatment follow-up.

[Partial replacement of the knee joint with patient-specific instruments and implants (ConforMIS iUni, iDuo)]. / Patientenspezifische Instrumente und Implantate beim Teilgelenkersatz des Kniegelenkes (ConforMIS iUni, iDuo).

Knee arthroplasty is a successful standard procedure in orthopedic surgery; however, approximately 20 % of patients are dissatisfied with the clinical results as they suffer pain and can no longer achieve the presurgery level of activity. According to the literature the reasons are inexact fitting of the prosthesis or too few anatomically formed implants resulting in less physiological kinematics of the knee joint. Reducing the number of dissatisfied patients and the corresponding number of revisions is an important goal considering the increasing need for artificial joints. In this context, patient-specific knee implants are an obvious alternative to conventional implants. For the first time implants are now matched to the individual bone and not vice versa to achieve the best possible individual situation and geometry and more structures (e.g. ligaments and bone) are preserved or only those structures are replaced which were actually destroyed by arthrosis. According to the authors view, this represents an optimal and pioneering addition to conventional implants. Patient-specific implants and the instruments needed for correct alignment and fitting can be manufactured by virtual 3D reconstruction and 3D printing based on computed tomography (CT) scans. The portfolio covers medial as well as lateral unicondylar implants, medial as well as lateral bicompartmental implants (femorotibial and patellofemoral compartments) and cruciate ligament-preserving as well as cruciate ligament-substituting total knee replacements; however, it must be explicitly emphasized that the literature is sparse and no long-term data are available.

Enoxaparin and rivaroxaban have different effects on human mesenchymal stromal cells in the early stages of bone healing.

OBJECTIVES: Venous thromboembolism (VTE) is a major potential complication following orthopaedic surgery. Subcutaneously administered enoxaparin has been used as the benchmark to reduce the incidence of VTE. However, concerns have been raised regarding the long-term administration of enoxaparin and its possible negative effects on bone healing and bone density with an increase of the risk of osteoporotic fractures. New oral anticoagulants such as rivaroxaban have recently been introduced, however, there is a lack of information regarding how these drugs affect bone metabolism and post-operative bone healing. METHODS: We measured the migration and proliferation capacity of mesenchymal stem cells (MSCs) under enoxaparin or rivaroxaban treatment for three consecutive weeks, and evaluated effects on MSC mRNA expression of markers for stress and osteogenic differentiation. RESULTS: We demonstrate that enoxaparin, but not rivaroxaban, increases the migration potential of MSCs and increases their cell count in line with elevated mRNA expression of C-X-C chemokine receptor type 4 (CXCR4), tumor necrosis factor alpha (TNFα), and alpha-B-crystallin (CryaB). However, a decrease in early osteogenic markers (insulin-like growth factors 1 and 2 (IGF1, IGF2), bone morphogenetic protein2 (BMP2)) indicated inhibitory effects on MSC differentiation into osteoblasts caused by enoxaparin, but not by rivaroxaban. CONCLUSIONS: Our findings may explain the adverse effects of enoxaparin treatment on bone healing. Rivaroxaban has no significant impact on MSC metabolism or capacity for osteogenic differentiation in vitro.Cite this article: Dr H. Pilge. Enoxaparin and rivaroxaban have different effects on human mesenchymal stromal cells in the early stages of bone healing. Bone Joint Res 2016;5:95-100. DOI: 10.1302/2046-3758.53.2000595.

Functional inhibition of mesenchymal stromal cells in acute myeloid leukemia.

Hematopoietic insufficiency is the hallmark of acute myeloid leukemia (AML) and predisposes patients to life-threatening complications such as bleeding and infections. Addressing the contribution of mesenchymal stromal cells (MSC) to AML-induced hematopoietic failure we show that MSC from AML patients (n=64) exhibit significant growth deficiency and impaired osteogenic differentiation capacity. This was molecularly reflected by a specific methylation signature affecting pathways involved in cell differentiation, proliferation and skeletal development. In addition, we found distinct alterations of hematopoiesis-regulating factors such as Kit-ligand and Jagged1 accompanied by a significantly diminished ability to support CD34+ hematopoietic stem and progenitor cells in long-term culture-initiating cells (LTC-ICs) assays. This deficient osteogenic differentiation and insufficient stromal support was reversible and correlated with disease status as indicated by Osteocalcin serum levels and LTC-IC frequencies returning to normal values at remission. In line with this, cultivation of healthy MSC in conditioned medium from four AML cell lines resulted in decreased proliferation and osteogenic differentiation. Taken together, AML-derived MSC are molecularly and functionally altered and contribute to hematopoietic insufficiency. Inverse correlation with disease status and adoption of an AML-like phenotype after exposure to leukemic conditions suggests an instructive role of leukemic cells on bone marrow microenvironment.

What is the predictive value of MRI for the occurrence of knee replacement surgery in knee osteoarthritis?

Knee osteoarthritis is associated with structural changes in the joint. Despite its many drawbacks, radiography is the current standard for evaluating joint structure in trials of potential disease-modifying osteoarthritis drugs. MRI is a non-invasive alternative that provides comprehensive imaging of the whole joint. Frequently used MRI measurements in knee osteoarthritis are cartilage volume and thickness; others include synovitis, synovial fluid effusions, bone marrow lesions (BML) and meniscal damage. Joint replacement is considered a clinically relevant outcome in knee osteoarthritis; however, its utility in clinical trials is limited. An alternative is virtual knee replacement on the basis of symptoms and structural damage. MRI may prove to be a good alternative to radiography in definitions of knee replacement. One of the MRI parameters that predicts knee replacement is medial compartment cartilage volume/thickness, which correlates with radiographic joint space width, is sensitive to change, and predicts outcomes in a continuous manner. Other MRI parameters include BML and meniscal lesions. MRI appears to be a viable alternative to radiography for the evaluation of structural changes in knee osteoarthritis and prediction of joint replacement.

Insufficient stromal support in MDS results from molecular and functional deficits of mesenchymal stromal cells.

Ineffective hematopoiesis is a major characteristic of myelodysplastic syndromes (MDS) causing relevant morbidity and mortality. Mesenchymal stromal cells (MSC) have been shown to physiologically support hematopoiesis, but their contribution to the pathogenesis of MDS remains elusive. We show that MSC from patients across all MDS subtypes (n=106) exhibit significantly reduced growth and proliferative capacities accompanied by premature replicative senescence. Osteogenic differentiation was significantly reduced in MDS-derived MSC, indicated by cytochemical stainings and reduced expressions of Osterix and Osteocalcin. This was associated with specific methylation patterns that clearly separated MDS-MSC from healthy controls and showed a strong enrichment for biological processes associated with cellular phenotypes and transcriptional regulation. Furthermore, in MDS-MSC, we detected altered expression of key molecules involved in the interaction with hematopoietic stem and progenitor cells (HSPC), in particular Osteopontin, Jagged1, Kit-ligand and Angiopoietin as well as several chemokines. Functionally, this translated into a significantly diminished ability of MDS-derived MSC to support CD34+ HSPC in long-term culture-initiating cell assays associated with a reduced cell cycle activity. Taken together, our comprehensive analysis shows that MSC from all MDS subtypes are structurally, epigenetically and functionally altered, which leads to impaired stromal support and seems to contribute to deficient hematopoiesis in MDS.

The distribution of nociceptive innervation in the painful hip: a histological investigation.

Our understanding of the origin of hip pain in degenerative disorders of the hip, including primary osteoarthritis, avascular necrosis and femoroacetabular impingement (FAI), is limited. We undertook a histological investigation of the nociceptive innervation of the acetabular labrum, ligamentum teres and capsule of the hip, in order to prove pain- and proprioceptive-associated marker expression. These structures were isolated from 57 patients who had undergone elective hip surgery (44 labral samples, 33 ligamentum teres specimens, 34 capsular samples; in 19 patients all three structures were harvested). A total of 15,000 histological sections were prepared that were investigated immunohistochemically for the presence of protein S-100, 68 kDa neurofilament, neuropeptide Y, nociceptin and substance P. The tissues were evaluated in six representative areas. Within the labrum, pain-associated free nerve ending expression was located predominantly at its base, decreasing in the periphery. In contrast, the distribution within the ligamentum teres showed a high local concentration in the centre. The hip capsule had an almost homogeneous marker expression in all investigated areas. This study showed characteristic distribution profiles of nociceptive and pain-related nerve fibres, which may help in understanding the origin of hip pain.

T2* mapping of hip joint cartilage in various histological grades of degeneration.

OBJECTIVE: To evaluate T2* values in various histological severities of osteoarthritis (OA). METHOD: Magnetic resonance imaging (MRI) and T2* mapping including a three-dimensional (3D) double-echo steady-state (DESS) sequence for morphological cartilage assessment and a 3D multiecho data image combination (MEDIC) sequence for T2* mapping were conducted in 21 human femoral head specimens with varying severities of OA. Subsequently, histological assessment was undertaken in all specimens to correlate the observations of T2* mapping with histological analyses. According to the Mankin score, four grades of histological changes were determined: grade 0 (Mankin scores of 0-4), grade I (scores of 5-8), grade II (scores of 9-10), and grade III (scores of 11-14). For reliability assessment, cartilage T2* measurements were repeated after 4 weeks in 10 randomly selected femoral head specimens. RESULTS: T2* values decreased significantly with increasing cartilage degeneration (total P-values <0.001) ranging from 36.3 ± 4.3 ms in grade 0 regions to 22.8 ± 4.3 ms in regions with grade III changes. Pearson correlation analysis proved a fair correlation between T2* values and Mankin score (correlation coefficient = -0.362) that was statistically significant (P-value <0.001). Intra-class correlation (ICC) analysis demonstrated high intra-observer reproducibility for the T2* measurement (ICC: 0.949, P < 0.001). CONCLUSIONS: Given the advantages of the T2* mapping technique with no need for contrast medium, high image resolution and ability to perform 3D biochemically sensitive imaging, T2* mapping may be a strong addition to the currently evolving era of cartilage biochemical imaging.

Migration pattern of cementless press fit cups in the presence of stabilizing screws in total hip arthroplasty.

The aim of this study was to evaluate the initial acetabular implant stability and late acetabular implant migration in press fit cups combined with screw fixation of the acetabular component in order to answer the question whether screws are necessary for the fixation of the acetabular component in cementless primary total hip arthroplasty. One hundred and seven hips were available for follow-up after primary THA using a cementless, porous-coated acetabular component. A total of 631 standardized radiographs were analyzed digitally by the "single-film-x-ray-analysis" method (EBRA). One hundred and one (94.4 %) acetabular components did not show significant migration of more than 1 mm. Six (5.6%) implants showed migration of more than 1 mm. Statistical analysis did not reveal preoperative patterns that would identify predictors for future migration. Our findings suggest that the use of screw fixation for cementless porous-coated acetabular components for primary THA does not prevent cup migration.

[Regeneration of osteochondral defects in the knee]. / Zelltherapie zur Knorpelregeneration im Kniegelenk.

The application of autologous cells is a standard procedure for the treatment of chondral lesions of the knee. Here, the most frequently used cells are differentiated chondrocytes (autologous chondrocyte implantation, ACI; matrix-induced autologous chondrocyte implantation, MACI). The enzymatic digestion of cartilage tissue by collagenase and isolation of chondrocytes followed by in vitro cultivation are associated with cellular de- and transdifferentiation. To prevent these effects some authors recommend 3D-cultures and culture medium supplementation of defined growth factors and cytokines. Another aim is the reduction of donor site morbidity. Therefore, different progenitor cell types were tested towards their potential for osteochondral regeneration. In particular, MSC derived from bone marrow include several advantages for the treatment of osteochondral defects such as unproblematic sampling, cultivation techniques, and a relatively high degree of biological safety. This review summarises the basic cellular principles as well as clinical results of cell therapeutics for the regeneration of osteochondral defects in the knee.

[Slipped capital femoral epiphysis]. / Epiphysenlösung.

Slipped capital femoral epiphysis (SCFE) is a common hip disorder in adolescence and should be diagnosed and treated surgically as soon as possible. The etiology, biomechanical, biochemical and hereditary factors are still under investigation. The classification of SCFE is based on the acuteness, clinical and radiomorphological findings. Avascular necrosis of the epiphysis (AVN) and chondrolysis occur more often in operated than in non-operated patients. Medium and long-term sequelae of SCFE are loss of function and degenerative joint disease due to femoroacetabular impingement (FAI) or consequences from complications such as AVN and chondrolysis. For mild slips the long-term prognosis is better than for moderate or severe slips. Higher grade unstable SCFE may benefit from reduction while in chronic slips corrective osteotomy may be indicated. Traditional osteotomy procedures, such as Imhäuser or Southwick intertrochanteric osteotomy are safe procedures but correct the deformity distant from the site of the deformity. The surgical dislocation with modified Dunn osteotomy according to Ganz allows the preparation of an extended retinacular soft tissue flap and offers an extensive subperiosteal exposure of the circumference of the femoral neck before reducing the slipped epiphysis anatomically. In cases of FAI due to mild deformities restoration of the head-neck offset via hip arthroscopy or surgical dislocation should be considered before higher grade cartilage damage occurs.

[Cartilage quality in finger joints: delayed Gd(DTPA)²-enhanced MRI of the cartilage (dGEMRIC) at 3T]. / Knorpelqualität an den Fingergelenken: delayed Gd(DTPA)²-enhanced MRI of the cartilage (dGEMRIC) bei 3T.

PURPOSE: To evaluate the feasibility of molecular cartilage MRI in finger joints. MATERIALS AND METHODS: Delayed Gd(DTPA)²-enhanced MRI of the cartilage (dGEMRIC) using a variable flip angle approach (VFA) was performed for the metacarpophalangeal (MCP) joints II and III in nine healthy volunteers and eighteen patients with rheumatoid arthritis (RA). The cartilage thickness was measured. Additionally, dGEMRIC was performed on proximal interphalangeal joints (PIP) in two patients with finger osteoarthritis (OA). RESULTS: the dGEMRIC index of the four evaluated cartilage areas was significantly decreased in RA patients compared to healthy subjects. The dGEMRIC index of MCP II phalangeal cartilage was 389.6 ± 85.5 msec vs. 558.7 ± 74.4 msec in healthy subjects. The metacarpal MCP II cartilage dGEMRIC index was 357.3 msec ± 97.1 msec vs. 490.0 ± 86.6 msec. The dGEMRIC indices of MCP III were: phalangeal 436.2 ± 113.6 msec in RA, 558.8 ± 115.5 msec in healthy subjects and metacarpal 398.0 ± 97.6 msec in RA and 529.6 ± 111.0 msec in healthy subjects. Age and cartilage thickness were not significantly different. In PIP joints of finger osteoarthritis patients, low dGEMRIC indices were noted, compared to the controls. CONCLUSION: The dGEMRIC of finger joints is feasible in patients with RA and finger OA. Morphologically normal cartilage shows significantly decreased dGEMRIC values in RA, pointing towards cartilage degeneration on a molecular level. Further studies are needed to establish the usefulness of this technique for early diagnosis, prognosis and therapy monitoring.

[Cell therapy in bone-healing disorders]. / Zelltherapie bei Knochenheilungsstörungen.

In addition to stabilizing osteosynthesis and autologous bone transplantation, so-called orthobiologics are playing an increasing role in the treatment of bone-healing disorders. Besides the application of different growth factors, new data in the literature suggest that cell therapeutic agents promote local bone regeneration. Due to ethical and biological considerations, clinical application of progenitor cells for the musculoskeletal system is limited to autologous postpartum stem cells. Here in particular, cell therapy with autologous progenitor cells in one surgical session has delivered first promising results. Based on a review of the literature and on our own experience with 75 patients, this article reviews the rationale and characteristics of the clinical application of cell therapy for the treatment of bony substance defects. Most clinical trials report successful bone regeneration after the application of mixed cell populations from bone marrow.

Spinning around or stagnation - what do osteoblasts and chondroblasts really like?

OBJECTIVE: The influence of cytomechanical forces in cellular migration, proliferation and differentiation of mesenchymal stem cells (MSCs) is still poorly understood in detail. METHODS: Human MSCs were isolated and cultivated onto the surface of a 3 x 3 mm porcine collagen I / III carrier. After incubation, cell cultures were transferred to the different cultures systems: regular static tissue flasks (group I), spinner flasks (group II) and rotating wall vessels (group III). Following standard protocols cells were stimulated lineage specific towards the osteogenic and chondrogenic lines. To evaluate the effects of applied cytomechanical forces towards cellular differentiation distinct parameters were measured (morphology, antigen and antigen expression) after a total cultivation period of 21 days in vitro. RESULTS: Depending on the cultivation technique we found significant differences in both gen and protein expression. CONCLUSION: Cytomechanical forces with rotational components strongly influence the osteogenic and chondrogenic differentiation.

[Delayed gadolinium enhanced MRI of cartilage (dGEMRIC): molecular MRI of hip joint cartilage]. / "Delayed Gadolinium Enhanced MRI of Cartilage" (dGEMRIC): Molekulare MRT-Bildgebung des Hüftgelenkknorpels.

Factors such as instability and impingement lead to early cartilage damage and osteoarthritis of the hip joint. The surgical outcome of joint-preserving surgery about the hip joint depends on the preoperative quality of joint cartilage.For in vivo evaluation of cartilage quality, different biochemically sensitive magnetic resonance imaging (MRI) procedures have been tested, some of which have the potential of inducing a paradigm shift in the evaluation and treatment of cartilage damage and early osteoarthritis.Instead of reacting to late sequelae in a palliative way, physicians could assess cartilage damage early on, and the treatment intensity could be adequate and based on the disease stage. Furthermore, the efficiency of different therapeutic interventions could be evaluated and monitored.This article reviews the recent application of delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) and discusses its use for assessing cartilage quality in the hip joint. dGEMRIC is more sensitive to early cartilage changes in osteoarthritis than are radiographic measures and might be a helpful tool for assessing cartilage quality.

[Radiological diagnosis of femoroacetabular impingement]. / Radiologische Diagnose des femoroazetabulären Impingements.

Femoroacetabular impingements (FAI) are due to an anatomical disproportion between the proximal femur and the acetabulum which causes premature wear of the joint surfaces. An operation is often necessary in order to relieve symptoms such as limited movement and pain as well as to prevent or slow down the degenerative process. The result is dependent on the preoperative status of the joint with poor results for advanced arthritis of the hip joint. This explains the necessity for an accurate diagnosis in order to recognize early stages of damage to the joint. The diagnosis of FAI includes clinical examination, X-ray examination and magnetic resonance imaging (MRI). The standard X-radiological examination for FAI is carried out using two X-ray images, an anterior-posterior view of the pelvis and a lateral view of the proximal femur, such as the cross-table lateral or Lauenstein projections. It is necessary that positioning criteria are adhered to in order to avoid distortion artifacts. MRI permits an examination of the pelvis on three levels and should also include radial planned sequences for improved representation of peripheral structures, such as the labrum and peripheral cartilage. The use of contrast medium for a direct MR arthrogram has proved to be advantageous particularly for representation of labrum damage. The data with respect to cartilage imaging are still unclear. Further developments in technology, such as biochemical-sensitive MRI applications, will be able to improve the diagnosis of the pelvis in the near future.

Hepatic failure after injury - a common pathogenesis with sclerosing cholangitis?

OBJECTIVE: Hepatic failure after trauma occurs in about 5 - 10 % of multiple injured patients. Mortality rate remains high and liver dysfunction might deteriorate to complete liver failure and contribute to multi organ failure (MOF). Pathogenesis is multifactorial and distinct mechanisms are unknown. METHODS: To get further knowledge about pathogenesis of posttraumatic liver failure we investigated clinical course, inflammatory mediators, ERCP and histologic findings in 7 patients [6 male, 1 female, mean age 45.7 +/- 12.1 years, mean ISS 38.4 +/- 10.8 pts. (range 25-58 pts.)] that evolved hepatic failure after major trauma. Mortality rate was 14 %. RESULTS: All patients presented with a prolonged shock period after trauma and severe respiratory failure requiring differentiated ventilatory support and prone positioning. Onset of significant bilirubinemia (> 2.0 mg/dl) was day 3 to 16 days (median 11 days) after trauma. Past medical history did not reveal any underlying liver disease in all patients. Pro-and anti-inflammatory parameters like WBC, Procalcitonin, IL-4, IL-10, IL-11, IL-12, and IL-18 remained close to healthy control values. CRP was elevated but did not correlate with Bilirubin. Transaminases (ALT, AST) remained close to normal values but increased during the further course, whereas alkaline phosphatase (aP) and gamma-glutamyl transpeptidase (gGT) were already significantly elevated even before Bilirubin (gammaGT: 394 +/- 317 U/l; controls: < 56 U/l; aP 557 +/- 311 U/l; controls: < 127 U/l). Although no cholestasis was proven in ultrasound and CT investigations, all patients underwent ERCP and liver biopsy. Here, all patients presented uniform signs of multiple strictures of the intrahepatic bile ducts and sclerosing cholangitis. CONCLUSIONS: Our data provide evidence that sclerosing cholangitis contributes to liver failure after trauma. The pathomorphologic picture can not distinguish between shock liver and sclerosing cholangitis. Ischemia during posttraumatic shock might be an early trigger of hepatic failure, supported by further contributing factors such as catecholamines, parenteral nutrition, and bacterial translocation. As specific therapy for sclerosing cholangitis does not exist yet, prevention of triggers is central to avoid progressive hepatic failure in those patients. Further prospective studies have to prove whether sclerosing cholangitis is commonly involved in the pathogenesis of liver failure after trauma and shock. If so, one might speculate that early therapy with ursodeoxycholic acid might be effective thus reducing incidence and/or severity of hepatic failure in the future.

[Indications and results of corrective pelvic osteotomies in developmental dysplasia of the hip]. / Indikation und Ergebnisse hüftnaher Osteotomien bei Dysplasie.

BACKGROUND: Joint-preserving reconstructive surgeries in children and adolescents remain challenging for orthopaedists with regard to indication and surgical technique. Besides skeletal maturity and tissue quality at the time of surgery, the kind and degree of deformity, the causative pathologies in secondary dysplasias, and the prognosis have to be considered when deciding for or against a surgical procedure. Developmental dysplasia of the hip (DDH) is the most frequent deformity that indicates reorienting surgery on the hip joint in children and adolescents. The aim of these procedures is to prevent early secondary osteoarthritis. For patients and families as well as for the orthopaedist, risk-benefit analysis is of major interest. METHODS: In this study, the surgical techniques and specialties of different reconstructive operations are presented. Based on a review of the literature, the results of defined surgical methods are discussed and compared with own experiences. RESULTS: Only limited information is available about the clinical long-term outcome after defined reconstructing surgery on the hip joint in children and adolescents. The degree of the deformity, the age of onset, and the surgical experience of the orthopaedist are crucial factors in decision making for or against a surgical treatment. In early childhood, acetabuloplasty and Salter osteotomy are widely accepted to correct DDH. Triple and periacetabular osteotomies are preferred and have shown promising results in late adolescence and young adults. When the triradiate cartilage (growth plate) is closed, good outcomes can be achieved by the Ganz osteotomy. Intertrochanteric varus and derotation osteotomies of the femur may serve as additional procedures for pelvic osteotomies and are rarely indicated as a single procedure today. CONCLUSION: Reconstructive surgery on the hip joint improves function and may prevent early osteoarthritis and delay progression of cartilage degeneration in most patients when the indication and surgical technique are appropriate.