Agreement Between Proximal Femoral Geometry and Component Design in Total Hip Arthroplasty: Implications for Implant Choice.

BACKGROUND: The present study aimed to analyze the agreement between proximal femoral geometry of adult hips and femoral component design in total hip arthroplasty. METHODS: Anatomical femoral offset (FOAnat) and the anatomical neck-shaft angle (NSAAnat) of 800 adult hips were measured by computed tomography scans, and anatomical femoral neck height (FHAnat) was calculated. Corresponding best-fit implants of the most common hip system (standard, high offset and varus variant) were identified for each hip. Finally, the precision of the best possible anatomic reconstruction was assessed. RESULTS: The mean FOAnat was 38.0 mm (range: 19.8-57.9 mm, standard deviation [SD]: 6.4 mm), the mean NSAAnat was 130.8° (range: 107.1°-151.9°; SD: 6.5°), and the mean FHAnat was 32.6 mm (range: 14.4-52.0 mm; SD: 5.5 mm). In 450 (56.3%) hips, the standard variant was identified to be the best-fit implant, followed by the varus (n = 282, 35.3%) and the high offset (n = 68, 8.5%) variants. The mean minimal distance from the best-fit implant was 4.5 mm (range: 0.1-20.2 mm, SD: 3.4 mm). Excellent agreement (distance: <2 mm) between hip anatomy and best-fit implant was found in 203 (25.4%) hips, combined excellent and acceptable agreement (distance: <6 mm) in 569 (71.1%) hips, whereas 213 (28.9%) hips were graded as poor (distance: ≥6 mm). CONCLUSION: The present study revealed a mismatch between proximal femoral anatomy of a relevant proportion of adult hips and implant geometry of the most common femoral component in total hip arthroplasty.

Calibration Marker Position in Digital Templating of Total Hip Arthroplasty.

BACKGROUND: We report a mathematical method to assess the vertical and horizontal positions of spherical radiopaque objects of known size in conventional radiographs. METHODS: The reliability and validity of the method were tested in an experimental setting and applied to 100 anteroposterior pelvic radiographs with external calibration markers and unilateral total hip arthroplasty (THA). RESULTS: We found excellent reliabilities; intraclass correlation coefficients for interobserver and intraobserver reliabilities were 0.999-1.000 (P = .000). The mean normal height of THA was 198 mm (range: 142-243 mm, standard deviation: 18 mm) above the detector. Vertical and horizontal external marker positions differed significantly from the true hip center (THA; P < .001 and P = .017). CONCLUSION: This method could enhance patient safety by enabling automated detection of malpositioned calibration markers by templating software.

The Influence of Hip Rotation on Femoral Offset Following Short Stem Total Hip Arthroplasty.

Short stem total hip arthroplasty (THA) is thought to be an advantageous surgical option for young patients. Femoral offset has been identified as an important factor for clinical outcome of THA. However, little is known on functional implications of femoral offset after short stem THA. Importantly, hip rotation influences the projected femoral offset and may lead to significant underestimation. Therefore, a novel method to identify and account for hip rotation was applied to a prospectively enrolled series of 37 patients (48 radiographs) undergoing short stem THA. Repeated measurements were performed and intraobserver and interobserver reliability was assessed and femoral offset was corrected for rotation. Based on this study, rotation-correction of femoral offset is of highest relevance for the correct interpretation in future studies.

Planning Results for High Tibial Osteotomies in Degenerative Varus Osteoarthritis Using Standing and Supine Whole Leg Radiographs.

OBJECTIVE: In this study, we hypothesized that standing and supine X-rays lead to different preoperative planning results. METHODS: The present study included 168 pictures from 81 patients who were treated surgically with high tibial osteotomy (HTO) for varus deformity between January 2017 and February 2018. Each patient underwent whole leg X-ray examinations in both standing and supine position. On both images, the following parameters were measured: degree of axis deviation (DAD), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), width of medial (MJS) and lateral joint space (LJS), and the correction angle (CA). The results were correlated with the patients' age and body mass index (BMI). To analyze intra-observer reliability, the same researcher, blinded to the previous measurements, remeasured all X-rays from 10 patients 8 weeks after the initial measurements were carried out. RESULTS: While mLDFA (P = 0.075), mMPTA (P = 0.435), and MJS (P = 0.119) did not show any differences between the two modalities, LJS (P = 0.016) and DAD (P < 0.001) differed significantly, leading to different correction angles (P < 0.001). The mean difference of the CA was 1.7° ± 2.2° (range, -2.6° to-15.4°). In 14 legs (17%), the standing X-ray led to a correction angle that was at least 3° larger than the calculation revealed in the supine X-ray; in 4 legs (5%), it was at least 5° larger. Increased BMI (r = 0.191, P = 0.088) and older age (r = 0.057 , P = 0.605) did not show relevant correlation with DAD differences. However, more severe varus malalignment in the supine radiograph did correlate moderately with differences of correction angles between supine and weight-bearing radiographs (r = 0.414, P < 0.001). The analysis of the intra-rater reliability revealed mediocre to excellent intercorrelation coefficients between the measurements of the observer. CONCLUSION: The use of supine and standing X-ray images leads to different planning results when performing high tibial osteotomies for varus gonarthrosis. To avoid potential overcorrection, surgeons might consider increased lateral joint spaces on standing radiographs in osteoarthritic knees with varus deviation.

Retention of Posterior Cruciate Ligament Alone May Not Achieve Physiological Knee Joint Kinematics After Total Knee Arthroplasty: A Retrospective Study.

BACKGROUND: The apparently physiological kinematics of the bicruciate-stabilized total knee arthroplasty (BCS TKA) systems have been attributed to the anterior and posterior post-cam mechanism. Although comparisons between TKA designs with either a retained or a sacrificed cruciate ligament have been conducted, we are not aware of any analyses of 2 implants with identical bearing geometry but different cruciate-ligament strategies under equal loading conditions. Knowledge about the kinematic effect of the different cruciate ligament strategies would potentially be valuable to facilitate preoperative planning and decision-making with regard to selecting the most appropriate implant for a patient. METHODS: This retrospective study included 20 patients: 10 treated with a BCS and 10 treated with a cruciate retaining (CR) TKA. Fluoroscopic analyses during high-flexion activities (unloaded flexion-extension and loaded lunge) were conducted at 24 months postsurgery. All patients completed the Knee Society Score, Forgotten Joint Score, and High-Flexion Knee Score questionnaires preoperatively and postoperatively. RESULTS: The BCS cohort showed greater femoral lateral rollback as well as a medial pivot in both activities. In contrast, the CR cohort showed a significant increase in anterior translation on the medial compartment as well as almost absent femoral lateral rollback. Higher clinical scores were observed in the BCS cohort. CONCLUSIONS: At 24 months postsurgery, despite equal bearing geometry, retention of the posterior cruciate ligament in the CR cohort apparently was insufficient to reduce anterior shift. The BCS cohort showed expected knee joint kinematics; however, the kinematics in this cohort could eventually benefit from a smooth transition between the interchanging surfaces. Further investigation should be focused on the surgical technique and its interaction with the TKA design. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Prognostic Value of Age and Early Magnetic Resonance Imaging in Patients with Cervical Subaxial Spinal Cord Injuries.

BACKGROUND AND OBJECTIVE: The predictive role of a patient's age in spinal cord injury (SCI) is still unclear given the coexistence of potential confounding factors, whether clinical or radiological. Thus, it is the aim of this work to assess the prognostic role of a patient's age against initial radiological features in a traumatic cervical SCI population. METHODS: Clinical and radiological data from patients with acute traumatic cervical SCI and a first MRI performed within 48 h of trauma were retrospectively reviewed. Patients were dichotomized according to the length intramedullary lesion, and associations between age and other clinical or radiological prognostic variables were analyzed. The receiver-operating characteristic (ROC) curve was used to test the discriminative capacity of the patient age to predict neurological and functional outcomes. Poor functional outcome was defined as a Walking Index Spinal Cord Injury score <1 and poor neurological outcome as the lack of neurological improvement between admission and follow up. RESULTS: 134 patients fulfilled the inclusion criteria and were analyzed. The mean age was 43 years, with a male/female ratio of 4:1. polytrauma and soft tissue injuries were inversely proportional to patient age (P < 0.001). A critical value of 55-year-old was established as a threshold for determining poor functional and neurological outcomes. Across the group of patients with minor intramedullary lesions, older age was correlated with poor functional and neurological outcomes (P < 0.001 and P = 0.04, respectively). CONCLUSIONS: Patient age is an important prognostic factor in patients with traumatic cervical SCI. Fifty-five years is the critical cutoff associated with poor prognostic outcome.

Panobinostat mediated cell death: a novel therapeutic approach for osteosarcoma.

Osteosarcoma is an aggressive cancer with a poor long term prognosis. Neo-adjuvant poly-chemotherapy followed by surgical resection remains the standard treatment, which is restricted by multi-drug resistance. If first-line therapy fails, disease control and patient survival rate drop dramatically. We aimed to identify alternative apoptotic mechanisms induced by the histone deacetylase inhibitor panobinostat in osteosarcoma cells. Saos-2, MG63 and U2-OS osteosarcoma cell lines, the immortalized human osteoblast line hFOB and the mouse embryo osteoblasts (MC3T3-E1) were treated with panobinostat. Real time viability and FACS confirmed the cytotoxicity of panobinostat. Cell stress/death related factors were analysed by RT-qPCR and western blot. Cell morphology was assessed by electron microscopy. 10 nM panobinostat caused cell viability arrest and death in all osteosarcoma and osteoblast cells. P21 up-regulation was observed in osteosarcoma cells, while over-expression of p73 was restricted to Saos-2 (TP53-/-). Survivin and Bcl-2 were suppressed by panobinostat. Endoplasmic reticulum (ER) stress markers BiP, CHOP, ATF4 and ATF6 were induced in osteosarcoma cells. The un-spliced Xbp was no further detectable after treatment. Autophagy players Beclin1, Map1LC3B and UVRAG transcripts over-expressed after 6 hours. Protein levels of Beclin1, Map1LC3B and p62 were up-regulated at 72 hours. DRAM1 was stable. Electron micrographs revealed the fragmentation and the disappearance of the ER and the statistically significant increase of autophagosome vesiculation after treatment. Panobinostat showed a synergistic suppression of survival and promotion of cell death in osteosarcoma cells. Panobinostat offers new perspectives for the treatment of osteosarcoma and other malignant bone tumours.

Effect of prolonged-released oxycodone/naloxone in postoperative pain management after total knee replacement: a nonrandomized prospective trial.

PURPOSE: The purpose of this study was to examine the effect of postoperative prolonged release oxycodone/naloxone (OXN) in comparison to other opioids (control group) on the early postoperative rehabilitation outcome after total knee replacement. METHODS: In a prospective, noninterventional, nonrandomized clinical trial, 80 patients were assigned to either the OXN group or a control group. Postoperative outcome and pain level at days 3, 6, 21, 35, and 6months were evaluated using the Bowel Function Index, Brief Pain Inventory Short Form questionnaire, the Hospital for Special Surgery score, modified Larson score, and the ability to attend physiotherapy. Medications were recorded and safety analysis was done. Both groups were compared using an analysis of covariance. RESULTS: There were no significant differences between both groups regarding pain levels. OXN group patients reported better bowel function (median values of 0.0 for the OXN group and 20.0 for the control group). No effect of treatment group (P=.19) and no treatment-by-visit interaction on Hospital for Special Surgery final score (P=.67) could be detected, but Larson function score in the early postoperative phase was significantly better in the OXN group (P=.018). The proportion of OXN group patients who were able to attend without any restriction was 58.1%. The proportions of patients in the OXN group and control group who experienced mild or moderate adverse drug reactions were 23.3% and 37.8%, respectively. There were no serious adverse drug reactions. CONCLUSION: In conclusion, OXN provides an effective analgesia and offers several benefits such as higher ability to participate in physiotherapy and better functional results. Incidence and severity of constipation can be reduced by using prolonged-released OXN as compared with other opioids.