Ergebnisse zementfreier Endoprothesen bei der nichttraumatischen Hüftkopfnekrose

AIM OF THE STUDY The results from 56 patients with osteonecrosis of the femoral head who underwent 66 uncemented total hip replacements were analyzed and compared with current reports in the literature on cemented endoprosthesis. METHODS In the retrospective study in 30 of those cases the Zweymuller and in 25 cases the HA-coated ABG prosthesis were used. In addition the results of 11 patients with a polyethylene Endler cup in combination with a Zweymuller stem are presented. The mean age at surgery was 48 years, the mean follow-up was 5.9 years. Clinical examination, registration of the Merle d'Aubigne score and a radiological examination were performed. RESULTS The clinical results did not…

Classification and Automated Interpretation of Spinal Posture Data Using a Pathology-Independent Classifier and Explainable Artificial Intelligence (XAI)

Clinical classification models are mostly pathology-dependent and, thus, are only able to detect pathologies they have been trained for. Research is needed regarding pathology-independent classifiers and their interpretation. Hence, our aim is to develop a pathology-independent classifier that provides prediction probabilities and explanations of the classification decisions. Spinal posture data of healthy subjects and various pathologies (back pain, spinal fusion, osteoarthritis), as well as synthetic data, were used for modeling. A one-class support vector machine was used as a pathology-independent classifier. The outputs were transformed into a probability distribution according to Plat…

Venous thromboembolism in patients hospitalized for hip joint replacement surgery

Venous thromboembolism (VTE) is a potentially life-threatening disease. Major transient risk factors include trauma, surgery, and immobilization. Patients undergoing hip joint replacement (HJR) are characterized by a high risk of postoperative VTE, but data on the time trends of VTE rates in this population are sparse.In an analysis of the German nationwide inpatient sample, we included all hospitalizations for elective primary HJR in Germany from 2005 to 2016. Time trends of the surgical procedure, overall death rates, and VTE rates were analysed, and predictors of VTE identified.Overall, 1,885,839 inpatients with elective primary HJR (59.1% women, 51.4% ≥70 years) were included in the ana…

Calf Blood Compound (CFC) and Homeopathic Drug Induce Differentiation of Primary Human Skeletal Muscle Cells.

AbstractThe use of injections to treat structural muscle injuries is controversially discussed. In our controlled in vitro study, we investigated the biological impact of Actovegin and Traumeel alone and in combination on primary human skeletal muscle cells. Cells were characterized by immunofluorescence staining for myogenic factor 5 (Myf5) and MyoD, and cultured with or without Actovegin and / or Traumeel. The effects of these agents were assayed by cell viability and gene expression of the specific markers MyoD, Myf5, neural adhesion molecule (NCAM), and CD31. Myotube formation was determined by myosin staining. Neither Actovegin nor Traumeel showed toxic effects or influenced cell viabi…

Standardisiertes postoperatives Schmerztherapieschema in der Orthopädie

In order to treat patients with postoperative acute pain effectively, we have developed a standardised algorithm for analgesia. This process includes three levels and the appropriate supply of medication. The therapy level is defined based on the scale of the operation. Accordingly, the prescription and handling of the pain medication is simplified for the attending physician and nurses. The pain level has to be measured by the nursing staff sing a visual analogue scale (VAS). Thus, the efficiency of the analgesics will be continuously evaluated and controlled. The standardised supply medication can be applied in those cases with pain levels > or = 4 (VAS). It is possible to up- or down-gra…

Exposure to radial extracorporeal shockwaves induces muscle regeneration after muscle injury in a surgical rat model

The leading cause of training interruption in sport is a muscle injury, for which the standard treatment is nonsteroidal anti-inflammatory drugs (NSAIDs). To find alternative treatments, we investigated whether the radial extracorporeal shockwave application (rESWT) could stimulate muscle regeneration. A lesion with complete rupture (grade III muscle tear) was set in the musculus rectus femoris of 12-week-old Wistar rats, and the NSAID diclofenac, rESWT, or a combined therapy were applied on day 0, 3, and 5 directly following the surgery. Rats were euthanized at 2, 4, and 7 days after surgery and the area of muscle lesion was excised for histological and gene expression analysis to determin…

One-stage bilateral versus unilateral short-stem total hip arthroplasty: A matched-pair analysis of 216 hips

Abstract Background One-stage, bilateral, short-stem total hip arthroplasty (1B-ssTHA) represents an alternative to staged, unilateral, short-stem total hip arthroplasty (U-ssTHA); however, the safety and reliability of 1B-ssTHA remain unknown. The objective of the present study was to compare the functional outcomes, complications, and mortality rates between 1B-ssTHA and U-ssTHA at mid-term. Methods A retrospective, matched-pair study was performed, including 216 short stems implanted in 162 patients. Among the study population, 54 patients were treated with 1B-ssTHA. Patients were matched by gender, age, body mass index (BMI), and American Society of Anesthesiologists (ASA) classificatio…

The internal calcar septum and its contact with the virtual stem in THR: a computer tomographic evaluation.

The internal calcar septum is a ridge of cortical bone protruding from the inner cortical wall of the proximal femur into the medullary canal. It extends from the lesser trochanter into the femoral neck and narrows the femoral cavity in its dorsal third. This region is essential for THR stability, but the degree of contact between the septum and standard THR implants has never been studied. We obtained CT scans of 50 arthrotic hip joints from patients requiring THR. Virtual stems (50 straight/wedge-shaped and 50 anatomic stems) were placed in CT images of the femora using a PC-based preoperative planning unit. The dimensions of the septum, degree and location of contact between the septum a…

Mechanical characterization of rose bengal and green light crosslinked collagen scaffolds for regenerative medicine

Abstract Collagen is one of the most important biomaterials for tissue engineering approaches. Despite its excellent biocompatibility, it shows the non-negligible disadvantage of poor mechanical stability. Photochemical crosslinking with rose bengal and green light (RGX) is an appropriate method to improve this property. The development of collagen laminates is helpful for further adjustment of the mechanical properties as well as the controlled release of incorporated substances. In this study, we investigate the impact of crosslinking and layering of two different collagen scaffolds on the swelling behavior and mechanical behavior in micro tensile tests to obtain information on its wearin…

Secondary Osseous Integration of Cementless Unicompartmental Knee Arthroplasty After Internal Fixation of a Felix Type IIIB Fracture

Case A 76-year-old man presented with periprosthetic tibial plateau fracture (TPF), with a completely loosened tibial component 3 weeks after cementless unicompartmental knee arthroplasty (UKA). Internal fixation by buttress plating was performed, and the tibial component was retained and left in situ primarily as a spacer. Revision was planned after fracture consolidation, but at 3 months, the patient was able to walk without support, without pain, and with full range of motion. At 1 year, he is free of complaints. The initial loosened tibial component reintegrated. Conclusion Internal fixation combined with preserving the loosened tibial component may be a treatment option for TPF involvi…

Dexamethasone Inhibits the Pro-Angiogenic Potential of Primary Human Myoblasts

Tissue regeneration depends on the complex processes of angiogenesis, inflammation and wound healing. Regarding muscle tissue, glucocorticoids (GCs) inhibit pro-inflammatory signalling and angiogenesis and lead to muscle atrophy. Our hypothesis is that the synthetic GC dexamethasone (dex) impairs angiogenesis leading to muscle atrophy or inhibited muscle regeneration. Therefore, this study aims to elucidate the effect of dexamethasone on HUVECs under different conditions in mono- and co-culture with myoblasts to evaluate growth behavior and dex impact with regard to muscle atrophy and muscle regeneration. Viability assays, qPCR, immunofluorescence as well as ELISAs were performed on HUVECs,…

Comparison of Postoperative Coronal Leg Alignment in Customized Individually Made and Conventional Total Knee Arthroplasty

Neutral coronal leg alignment is known to be important for postoperative outcome in total knee arthroplasty (TKA). Customized individually made implants (CIM) instrumented with patient-specific cutting guides are an innovation aiming to increase the precision and reliability of implant positioning and reconstruction of leg alignment. We aimed to compare reconstruction of the hip–knee–ankle angle (HKA) of the novel CIM system iTotal™ CR G2 (ConforMIS Inc.) to a matched cohort of the off-the-shelf (OTS) knee replacement system Vanguard™ CR (Zimmer Biomet). Retrospective analysis of postoperative coronal full-leg weight-bearing radiographs of 562 TKA (283 CIM TKA, 279 OTS TKA) was conducted. V…

Preserving the abductor mechanism in robotic THR: the influence of stem design and cutterpath.

The tip of the greater trochanter is the attachment site for the abductor muscles of the hip joint. Its preservation in robotic and conventional THR is important for normal gait. The effect of different stem designs and robotic cutterpaths on the preservation of the trochanter tip is examined.One anatomical stem, one straight stem, and one stem specifically designed for robotic THR were implanted virtually in CT scans of osteoarthrotic hip joints using the Torch preoperative planning unit (URS-ortho). In transverse sections of the trochanter tip, dimensions of the trochanter area removed by the milling tool were recorded for each stem design and different cutterpaths (3-axis versus 5-axis m…

Biological responses to individualized small titanium implants for the treatment of focal full-thickness knee cartilage defects in a sheep model.

Abstract Background The present study aimed to evaluate the functional, radiological and histological outcome of a customized focal implant for the treatment of focal full-thickness cartilage defects in sheep. Methods The study used magnetic resonance imaging data as the basis for construction of the titanium implant using a three-dimensional printing technique. This was then placed on the medial condyle of the knee joint in eight sheep and left in place in vivo over a period of six months. Following euthanasia, the local biological response was analyzed using micro-computed tomography, light microscopy and histological evaluation (International Cartilage Repair Society (ICRS) score). The v…

Mechanisms of Disease: molecular insights into aseptic loosening of orthopedic implants

Despite the success of treating rheumatic disorders with biologic therapies, joint replacement surgery still remains the final treatment option in many cases. Approximately 1.5 million joint arthroplastic operations are performed annually worldwide. Implant failure due to massive bone loss and aseptic loosening of prostheses, however, is a major complication of joint replacement, which can lead to high socioeconomic burdens both for the individual patient and for health-care systems. To date, there is no approved drug therapy to prevent or inhibit periprosthetic osteolysis, and aseptic loosening of prostheses can only be overcome by surgical revision. Research during the past decade, howeve…

Impingement of the Sciatic Nerve due to a Protruding Acetabular Cage Rim

Abstract Sciatic nerve damage is a well-known complication that occurs in 1.5% of patients after primary total hip arthroplasty and in 8% after revision total hip arthroplasty. Yet when considering re-revision arthroplasty and acetabular cage implantation, incidence and management remain unclear. This case report describes a young female patient with sciatic nerve impingement after acetabular cage implantation. Her primary complaint was shooting sciatic left leg pain, worsening on ambulation and when seated. A complete workup was negative for spinal impingement or infection, and axonal nerve damage was confirmed through nerve conduction studies. The intraoperative findings showed that it wa…

The PROMISE study protocol: a multicenter prospective study of process optimization with interdisciplinary and cross-sectoral care for German patients receiving hip and knee endoprostheses

Background and purpose — Knee and hip replacement are common and increasing procedures, and an optimized care process that could be implemented in different settings would be useful. The PROMISE trial investigates whether a new care process works equally in different German settings and how the results compare with current non-standardized care. Patients and methods — This multi-center prospective mixed-method study includes 2,000 German patients receiving arthritis-related hip or knee endoprostheses. An interdisciplinary and cross-sectoral care process was developed and implemented in 3 German hospitals with different levels of care, and corresponding rehabilitation centers were included t…

Arthrose und Osteoporose - Wirklich eine inverse Relation?

Objective Increasing bone mineral density (BMD) has been found in several studies in patients with osteoarthritis (OA). Therefore, the simultaneous occurrence of osteoporosis (OP) and OA is denied by many clinicians. Because of our clinical impression, however, we suggest that we have to consider a common occurrence. In the present study we have examined the relationship between osteoathritis of the knee or the hip and osteoporosis. Method The BMD of the lumbar spine and the proximal femur of 117 OA patients (82 postmenopausal female patients aged 50-83 and 35 male patients aged 36-86 years) who subsequently required hip or knee replacements, but were otherwise healthy, was measured by dual…

General method for automated feature extraction and selection and its application for gender classification and biomechanical knowledge discovery of sex differences in spinal posture during stance and gait

Modern technologies enable to capture multiple biomechanical parameters often resulting in relational data. The current work proposes a generally applicable method comprising automated feature extraction, ensemble feature selection and classification to best capture the potentials of the data also for generating new biomechanical knowledge. Its benefits are demonstrated in the concrete biomechanically and medically relevant use case of gender classification based on spinal data for stance and gait. Very good results for accuracy were obtained using gait data. Dynamic movements of the lumbar spine in sagittal and frontal plane and of the pelvis in frontal plane best map gender differences.

Can hip resurfacing be safely revised with short-stem total hip arthroplasty? A case series of six patients.

Abstract Background The usage of short stems in primary total hip arthroplasty (THA) has constantly gained popularity over the last decade, however, to date, short stems are not eligible to be used as revision implants. The aim of this study was to retrospectively evaluate the outcome of revision surgery of failed hip resurfacing arthroplasty (HRA) using short-stem THA. Methods In a single center, retrospective analysis, 6 consecutive patients who were treated with a calcar-guided short stem after failure of HRA were evaluated. The mean follow-up was 3.25 years (SD 0.45). Patient reported outcome measurements (PROMs) were recorded using the Harris hip score (HHS) and The Western Ontario and…

Postoperative analgesic efficacy of peripheral levobupivacaine and ropivacaine: a prospective, randomized double-blind trial in patients after total knee arthroplasty.

BACKGROUND: Several previous trials have characterized the intra- and postoperative effects of the recently introduced local anesthetics, levobupivacaine and ropivacaine, for a variety of continuous peripheral nerve blocks. METHODS: We compared the analgesic efficacy of levobupivacaine 0.125% versus ropivacaine 0.2% via patient-controlled femoral nerve analgesia after total knee arthroplasty. In a double-blind, randomized, prospective design, 60 patients received femoral infusion with either substance. We analyzed postoperative local anesthetic consumption, pain scores, motor block, and opioid requirements over 72 h. RESULTS: Pain scores, motor block incidence, and opioid requirements were …

Machine learning techniques demonstrating individual movement patterns of the vertebral column: the fingerprint of spinal motion

Surface topography systems enable the capture of spinal dynamic movement; however, it is unclear whether vertebral dynamics are unique enough to identify individuals. Therefore, in this study, we investigated whether the identification of individuals is possible based on dynamic spinal data. Three different data representations were compared (automated extracted features using contrastive loss and triplet loss functions, as well as simple descriptive statistics). High accuracies indicated the possible existence of a personal spinal 'fingerprint', therefore enabling subject recognition. The present work forms the basis for an objective comparison of subjects and the transfer of the method to…

Return to Sports and Recreational Activity After Single-Stage Bilateral Short-Stem Total Hip Arthroplasty: 5-Year Results of a Prospective Observational Study

Background:Single-stage bilateral total hip arthroplasty (THA) is an alternative to staged unilateral THA in patients suffering from bilateral hip arthritis; however, there is still broad concern regarding the safety and reliability of this procedure. Short-stem THA has emerged in recent years. To date, no data are available on sports and recreational activity levels after single-stage bilateral short-stem THA in the general patient population.Hypothesis:Patients who have undergone single-stage bilateral short-stem THA return to a satisfying level of sports and recreational activity at midterm follow-up.Study Design:Case series; Level of evidence, 4.Methods:A total of 54 consecutive patient…

Molekulare Signalwege der aseptischen Endoprothesenlockerung (Molecular pathways in aseptic loosening of orthopaedic endoprosthesis)

Operative joint replacement to treat disabling joint conditions secondary to degenerative and inflammatory arthritides has become one of the most efficacious and cost-effective procedures to relieve pain and restore joint function. However, prosthetic implants are not built to last forever and osteolysis and aseptic loosening has been associated with prosthetic arthroplasties since their introduction. The functional life of a synthetic joint is influenced by many factors including the material of the implant, operation procedures and the surgeon involved, as well as patient-related factors. Although promising developments have been achieved in this field, more than 10% of all implants still…

Hip arthroplasty - All problems solved or still place for improvement?