A scoping review of human skeletal kinematics research using biplane radiography.

Biplane radiography has emerged as the gold standard for accurately measuring in vivo skeletal kinematics during physiological loading. The purpose of this scoping review was to map the extent, range, and nature of biplane radiography research on humans from 2004 through 2022. A literature search was performed using the terms biplane radiography, dual fluoroscopy, dynamic stereo X-ray, and biplane videoradiography. All articles referenced in included publications were also assessed for inclusion. A secondary search was then performed using the names of the most frequently appearing principal investigators among included papers. A total of 379 manuscripts were identified and included. The first studies published in 2004 focused on the native knee, followed by studies of the ankle joint complex in 2006, the shoulder in 2007, and the spine in 2008. Nearly half (180, 47.5%) of all manuscripts investigated knee kinematics. The average number of publications increased from 21.6 per year from 2012 to 2017 to 34.6 per year from 2017 to 2022. The average number of participants per study was 16, with a range from 1 to 101. A total of 90.2% of studies featured cohorts of 30 or less. The most prolific research groups for each joint were: Mass General Hospital (lumbar spine and knee), Henry Ford Hospital (shoulder), the University of Utah (ankle and hip), The University of Pittsburgh (cervical spine), and Brown University (hand/wrist/elbow). Future advancements in biplane radiography research are dependent upon increased availability of these imaging systems, standardization of data collection protocols, and the development of automated approaches to expedite data processing.

Radial and longitudinal meniscus tears show different gapping patterns under stance phase conditions.

Meniscal tearing can increase the contact pressure between the tibia and femur by causing gapping of torn meniscus tissue. The aim of this study was to quantify gapping behavior of radial and longitudinal tears and their impact on peak contact pressure and mean contact area. Twelve porcine knee joints underwent unicondylar, convertible osteotomy for exact tear application and consecutive suturing. Six tantalum marker beads were positioned along meniscus tears. The joints were preloaded with sinusoidal loading cycles ranging between 0 N and 350 N. Peak load was held constant and two synchronized Roentgen stereophotogrammetric analysis x-ray images were obtained to evaluate gapping, peak contact pressure and mean contact area in the native, torn and repaired states. There was no change in gapping or peak contact pressure in longitudinal tear. By contrast, the radial tear led to a significant gapping when compared to the native state, while the inside-out suture was able to restore gapping in parts of the meniscus. An increase in contact pressure after radial tear was detected, which was again normalized after suturing. The most important finding of the study is that longitudinal tears did not gap under pure axial loading, whereas radial tears tended to separate the tear interfaces.

Less wear in deep-dished mobile compared to fixed bearing total knee arthroplasty of the same design at 5-year follow-up: a randomised controlled model-based Roentgen stereophotogrammetric analysis trial.

PURPOSE: The aim of this prospective randomised controlled study was to compare wear characteristics and functional outcome between deep-dished mobile bearing (MB) and fixed bearing (FB) cemented total knee arthroplasty (TKA). We hypothesised that deep-dished MB reduces polyethylene wear and improves patient-reported outcome measures. METHODS: A total of 50 patients were randomised to receive a MB or FB tibia component of the same cemented TKA design. Patients were evaluated over a 5-year follow-up period. Medial and lateral wear were assessed using model-based Roentgen Stereophotogrammetric Analysis (RSA) and compared with the direct postoperative minimal joint space measurement. Functional outcome was assessed by the clinician-derived KSS and OKS, WOMAC, LEAS, and FJS-12. All data were derived using a general linear mixed model. RESULTS: At 5-year follow-up, decreased wear in the MB compared to the FB group was observed on the lateral side (0.07 ± 0.17 mm, p = 0.026), but not on the medial side (0.31 ± 0.055 mm, p = 0.665). Functional outcomes improved with a statistical significant effect over time, with no significant differences between groups (all p > 0.17). CONCLUSION: This model-based RSA study with 5-year follow-up showed that cemented deep-dished MB reduced lateral polyethylene wear as compared to FB in a single TKA system, whilst clinical outcomes were comparable. Longer follow-up is needed to establish clinical implications of these altered wear patterns and determine type of wear. LEVEL OF EVIDENCE: Level 1 randomised controlled trial.

Accuracy of radiostereometric analysis using a motorized Roentgen system in a pilot study for clinical simulation.

Radiostereometric analysis (RSA) is routinely implemented with two paired Roentgen tubes for three-dimensional (3D) implant migration measurements. A conventional set-up of one stationary tube and one mobile could be time-consuming. Utilizing two customized ceiling-mounted tubes is normally associated with investment costs. Thus, a pilot set-up of a motorized system (single Roentgen source) for radiostereometric image acquisition may be a time-saving and space-efficient alternative. RSA using the motorized system is feasible in this study as a non-synchronized image acquisition technique, however, patient motion may occur and influence the assessment of implant migration. The phantom study aimed to assess accuracy of RSA using the motorized Roentgen system in this in vitro study. Accuracy values of translations and rotations were ±0.29 mm and ±0.48° for the single Roentgen source RSA set-up and ±0.26 mm and ±0.48° for the conventional RSA set-up. This study was also performed to simulate potential patient motion during exposure intervals between paired image acquisition. RSA using the motorized system is able to implement RSA with acceptable accuracy. In general, RSA with synchronized image acquisition is the gold standard to access in vivo implant migration with the highest accuracy. Patient motion exists in non-synchronized image acquisition techniques and results in RSA-related motion artifacts. Then we introduced what RSA-related motion artifacts are. The uniplanar calibration cage applied in the study has a few fiducial and control markers, and some of the markers were occluded in radiographs. Whereas, the number of markers in the calibration cage is correlated with accuracy of 3D implant reconstruction.

Migration behaviour of 2 clinically excellent cementless stems with different design rationales: 5-year follow-up of a randomised RSA-study.

INTRODUCTION: Excellent long-term survival has been reported for both the Taperloc and the Mallory-Head cementless stems. However, little is known about the migration behaviour of these stems which have different design rationales. The purpose of this randomised clinical trial was to compare the migration and clinical outcomes of these stems during 5 years of follow-up. METHODS: 42 consecutive hips in 38 patients scheduled to receive cementless THA were randomised to either a Taperloc or a Mallory-Head stem. Evaluation took place preoperatively and postoperatively on the second day, at 6, 12, 26, and 52 weeks, and annually thereafter. Primary outcome was stem migration measured using roentgen stereophotogrammetric analysis (RSA) and secondary outcomes were the Harris Hip Score (HHS) and 36-Item Short-Form Health Survey (SF-36). No patients were lost to follow-up; in 1 patient the THA was removed due to deep infection 3 months postoperatively. In 6 hips migration measurements were not possible due to insufficient marker configuration. RESULTS: Throughout the follow-up period of 5 years, 3-dimensional migration was comparable between the Taperloc and the Mallory-Head stems (p-values > 0.05). However, at the 5-year follow-up point the retroversion of the Mallory-Head stem was 0.9° more than the Taperloc stem (p = 0.04). Initial subsidence and retroversion were respectively as large as 6.8 mm and 3.6° for the Taperloc stem and 5 mm and 3.6° for the Mallory-Head stem. After the first postoperative year, both implants had stabilised. The mean increment of HHS, as well as the SF-36 scores during the 5-year follow-up, were comparable between the 2 stems. CONCLUSIONS: The excellent long-term survival of both designs was confirmed in this study showing comparable initial migration with subsequent stabilisation. However, the Taperloc design with a flat, wedged geometry showed better rotational stability.

HUMANIZED MODEL OF ISOLATED SUSPENSION CULTIVATION OF HEMATOPOIETIC PROGENITOR CELLS FOR THE INVESTIGATION OF IONIZING RADIATION INFLUENCE IN VIVO. / GUMANIZOVANA MODEL' KUL'TYVUVANNIa IZOL'OVANOÏ SUSPENZIÏ GEMOPOETYChNYKh KLITYN/POPEREDNYTs' DLIa VYVChENNIa VPLYVU IONIZUIuChOÏ RADIATsIÏ IN VIVO.

OBJECTIVE: development of the humanized system for cells cultivation outside the human organism (human-mouse)and investigation of the influence of ionizing radiation in increasing doses on the colony-forming ability ofhematopoietic progenitor cells. MATERIALS AND METHODS: Bone marrow samples of individuals without blood system diseases were cultivated in geldiffusion chambers with semi-solid agar in the abdominal cavity of CBA mice exposed to ionizing radiation action.Cell aggregates, which were obtained in the culture of diffusion chambers in vivo, were counted and colony-formingefficiency of bone marrow cells was determined. RESULTS: We revealed the stimulation of colony forming under the action of ionizing radiation in increasing doseson the animals-recipients of the chambers, which indirectly indicates the synthesis of colony-stimulating factor inthe mice organism and its permeation into the diffusion chambers with human bone marrow cells. The effect of cyto-statics action on the mice organism was investigated, which in experimentally selected dose cause stimulation ofcolony forming in cell cultures, both 24 hours and 2 hours after administration. CONCLUSIONS: The ability of hematopoietic progenitor cells of bone marrow to form colonies and clusters was eval-uated during the cultivation in semi-solid agar in gel diffusion chambers in vivo, as well as the association with thenumber of explanted cells in the appropriate range was established, which indicates the clonal nature of cell aggre-gates growth in culture. It was shown that the treatment of animals the day prior to experiment with administra-tion of cytostatics is comparable to the action of ionizing radiation and can be used to study hematopoiesis in«human-mouse¼ system.

Highly cross-linked versus conventional polyethylene inserts in total hip arthroplasty, a five-year Roentgen stereophotogrammetric analysis randomised controlled trial.

BACKGROUND: Polyethylene (PE) particles produced by wear of the acetabular insert are thought to cause osteolysis and thereby aseptic loosening of the implant in total hip arthroplasty (THA). As highly cross-linked polyethylene (HXLPE) is presumed to give lower wear rates, in vivo studies are needed to confirm this. AIM: To compare the wear of REXPOL, a HXPLE, with conventional PE within the first five years after implantation using Roentgen stereophotogrammetric analysis (RSA). METHODS: Patients were randomised to receive either a HXLPE (REXPOL) or a conventional PE insert during primary THA. RSA images were obtained directly postoperative and after 6 wk, 12 wk, 6 mo, 12 mo, 24 mo and five years. Functional outcomes were assessed using the Hip Injury and Osteoarthritis Outcome Score and Harris Hip Score at baseline and five years after surgery. RESULTS: The HXLPE (REXPOL) showed less wear in the latero-medial direction. Significant wear rates of conventional PE were seen in the latero-medial and center-proximal direction and in volume and corrected volume, whereas the REXPOL did not show these outcomes over time. Improvement from baseline in functional outcome did not significantly differ. CONCLUSION: Total 3D wear is less in THAs inserted with a REXPOL inlay than a conventional PE inlay after five years. This study confirms, for the first, that the REXPOL HXLPE inlay is preferred to standard PE.

Fixation of the short global tissue-sparing hip stem.

AIMS: Short, bone-conserving femoral components are increasingly used in total hip arthroplasty (THA). They are expected to allow tissue-conserving implantation and to render future revision surgery more straightforward but the long-term data on such components is limited. One such component is the global tissue-sparing (GTS) stem. Following the model for stepwise introduction of new orthopaedic implants, we evaluated early implant fixation and clinical outcome of this novel short-stem THA and compared it to that of a component with established good long-term clinical outcome. METHODS: In total, 50 consecutive patients ≤ 70 years old with end-stage symptomatic osteo-arthritis were randomized to receive THA with the GTS stem or the conventional Taperloc stem using the anterior supine intermuscular approach by two experienced hip surgeons in two hospitals in the Netherlands. Primary outcome was implant migration. Patients were followed using routine clinical examination, patient reported outcome using Harris Hip Score (HHS), Hip Disability And Osteoarthritis Outcome Score (HOOS), EuroQol five-dimension questionnaire (EQ5D), and Roentgen Stereophotogrammetric Analysis (RSA) at three, six, 12, and 24 months. This study evaluated the two-year follow-up results. RESULTS: In addition to the initial migration pattern of distal migration (subsidence, Y-translation) and retroversion (Y-rotation) also exhibited by the Taperloc stem, the GTS stem showed an initial migration pattern of varization (X-translation combined with Z-rotation) and posterior translation (Z-translation). However, all components stabilized aside from one Taperloc stem which became loose secondary to malposition and was later revised. Clinical outcomes and complications were not statistically significantly different with the numbers available. CONCLUSION: A substantially different and more extensive initial migration pattern was seen for the GTS stem compared to the Taperloc stem. Although implant stabilization was achieved, excellent long-term survival similar to that of the Taperloc stem should not be inferred. Especially in the absence of clinically proven relevant improvement, widespread usage should be postponed until long-term safety has been established. Cite this article: Bone Joint J 2020;102-B(6):699-708.

Model-Based Roentgen Stereophotogrammetric Analysis to Monitor the Head-Taper Junction in Total Hip Arthroplasty in Vivo-And They Do Move.

Model-based Roentgen stereophotogrammetric analysis (RSA) using elementary geometrical shape (EGS) models allows migration measurement of implants without the necessity of additional attached implant markers. The aims of this study were: (i) to assess the possibility of measuring potential head-taper movement in THA in vivo using model-based RSA and (ii) to prove the validity of measured head-taper migration data in vitro and in vivo. From a previous RSA study with a 10 years follow-up, retrospectively for n = 45 patients head-taper migration was calculated as the relative migration between femoral ball head and taper of the femoral stem using model-based RSA. A head-taper migration of 0.026 mm/year can be detected with available RSA technology. In vitro validation showed a total migration of 268 ± 11 µm along the taper axis in a similar range to what has been reported using the RSA method. In vivo, a proof for interchangeable applicability of model-based RSA (EGS) and standard marker-based RSA methods was indicated by a significant deviation within the migration result after 12-month follow-up for all translation measurements, which was significantly correlated to the measured head-taper migration (r from 0.40 to 0.67; p < 0.05). The results identified that model-based RSA (EGS) could be used to detect head-taper migration in vivo and the measured movement could be validated in vitro and in vivo as well. Those findings supported the possibility of applying RSA for helping evaluate the head-taper corrosion related failure (trunnionosis).

Clinical evaluation of a novel press-fit acetabular cup using "Ein-Bild-Roentgen-Analysis" (EBRA): A positive short-term prognosis.

INTRODUCTION: Demographic change and demand for high quality of life lead to increasing implantation numbers. Aim of this study was to compare the Plasmafit® cup to Allofit® and Plasmacup®. METHODS: The study included 174 patients who had received 33 Plasmacup®, 68 Allofit® and 73 Plasmafit® cup implants. These were reviewed postoperatively, after 6 months control and after 12 months. RESULTS: No significant progressive migration could be discovered in any of the cup systems. At each follow-up the cups showed nearly constant values. CONCLUSIONS: All examined acetabular cups showed excellent migration behavior within the first 12 postoperative months.

Spectacular rediscovery of the original prints of radiographs Roentgen sent to Lorentz in 1896.

BACKGROUND: Ninety years after the Dutch theoretical physicist H.A. Lorentz died, detailed investigation of his scientific heritage yielded the set of nine original prints of radiographs that W.C. Roentgen made during his experiments and had sent him, among half a dozen other scientists, on January 1st, 1896. MAIN TEXT: Through communications with different experts and literature research, the author describes these nine prints and how they relate to the first publication Roentgen wrote about his discovery of the X-rays. CONCLUSIONS: The combination of Roentgen's first publication on his X-ray discovery and the nine radiographs provides insight as to which aspects of the discovery were considered important by Roentgen and how he carried out the experiments to be able to describe these aspects.

[Imaging in patients with axial spondylarthritis with focus on new bone formation]. / Bildgebung bei Patienten mit axialer Spondyloarthritis mit Fokus auf die Knochenneubildung.

To summarize, the currently available imaging procedures have various possibilities to visualize or sometimes to predict the osteogenesis pathognomonic for axial spondylarthritis (axSpA). The individual imaging techniques of X­rays, computed tomography (CT) and magnetic resonance imaging (MRI) all have strengths and weaknesses in the diagnostics of axSpA. The generally easily available X­ray imaging rapidly provides information on the condition of large sections of the skeleton. In particular, it can depict the chronic stages with various structural alterations of the sacroiliac joint and syndesmophytes and ankylosis of the spine. The CT technique, which principally has the same contrast as X­rays, also shows pathological ossifications but without superimpositions, with better resolution of details and a higher dimensionality. The MRI technique has a superior soft tissue contrast so that acute inflammatory stages, such as bone marrow edema and erosion of the edges of vertebrae of the spine (shiny corners, Romanus lesions) or erosions and bone marrow edema of the sacroiliac joint are easily visible. Bony reconstruction processes can be visualized better in X­ray imaging and particularly in CT, which increases the evidential value of X­ray, CT and MRI techniques. The positions of conventional radiography and MRI are well-established in the diagnostic algorithm; however, low-dose CT of the spine is still in the experimental stage but the initial results look promising.

The beginnings of radiology in Malaga. / Los inicios de la radiología en Málaga.

On March 2, 1896, the local press in Malaga reported the discovery of X-rays, relating various news items about the use of X-rays and literature about Roentgen's discovery by journalists and other authors. Outstanding among these writings was a periodical directed at the administration and general public called Los Rayos X. Progressively, the first X-ray machines were installed in hospitals during this period, and the first installation in a private medical clinic took place in 1900. In Malaga, the assimilation and progression of the diagnostic and therapeutic use of radiology was slow and affected by peculiarities owing to the social, economic, and cultural circumstances of the period. Influential physicians willing to overcome resistance to advances were able to bring medical practice in Malaga to a level similar to that of other cities.

Model-based roentgen stereophotogrammetric analysis using elementary geometrical shape models: 10 years results of an uncemented acetabular cup component.

BACKGROUND: Non-cemented acetabular cup components demonstrated different clinical performance depending on their surface texture or bearing couple. However, clinical osseointegration needs to be proved for each total joint arthroplasty (TJA) design. Aim of this study was to detect the in vivo migration pattern of a non-cemented cup design, using model-based roentgen stereophotogrammetric analysis with elementary geometrical shape models (EGS-RSA) to calculate early cup migration. METHODS: Interchangeable applicability of the model-based EGS-RSA method next to gold standard marker-based RSA method was assessed by clinical radiographs. Afterwards, in vivo acetabular cup migration for 39 patients in a maximum follow up of 120 months (10 years) was calculated using model-based EGS-RSA. RESULTS: For the axes with the best predictive capability for acetabular cup loosening, mean (±SD) values were calculated for migration and rotation of the cup. The cup migrated 0.16 (±0.22) mm along the cranio-caudal axis after 24 months and 0.36 (±0.72) mm after 120 months, respectively. It rotated - 0.61 (±0.57) deg. about the medio-lateral axis after 24 months and - 0.53 (±0.67) deg. after 120 months, respectively. CONCLUSIONS: Interchangeable applicability of model-based EGS-RSA next to gold standard marker-based RSA method could be shown. Model-based EGS-RSA enables an in vivo migration measurement without the necessity of TJA specific surface models. Migration of the investigated acetabular cup component indicates significant migration values along all the three axes. However, migration values after the second postoperative year were within the thresholds reported in literature, indicating no risk for later aseptic component loosening of this TJA design.

Low-field magnetic resonance imaging offers potential for measuring tibial component migration.

BACKGROUND: Roentgen stereophotogrammetric analysis (RSA) is used to measure early prosthetic migration and to predict future implant failure. RSA has several disadvantages, such as the need for perioperatively inserted tantalum markers. Therefore, this study evaluates low-field MRI as an alternative to RSA. The use of traditional MRI with prostheses induces disturbing metal artifacts which are reduced by low-field MRI. The purpose of this study is to assess the feasibility to use low-field (0.25 Tesla) MRI for measuring the precision of zero motion. This was assessed by calculating the virtual prosthetic motion of a zero-motion prosthetic reconstruction in multiple scanning sessions. Furthermore, the effects of different registration methods on these virtual motions were tested. RESULTS: The precision of zero motion for low-field MRI was between 0.584 mm and 1.974 mm for translation and 0.884° and 3.774° for rotation. The manual registration method seemed most accurate, with µ ≤ 0.13 mm (σ ≤ 0.931 mm) for translation and µ ≤ 0.15° (σ ≤ 1.63°) for rotation. CONCLUSION: Low-field MRI is not yet as precise as today's golden standard (marker based RSA) as reported in the literature. However, low-field MRI is feasible of measuring the relative position of bone and implant with comparable precision as obtained with marker-free RSA techniques. Of the three registration methods tested, manual registration was most accurate. Before starting clinical validation further research is necessary and should focus on improving scan sequences and registration algorithms.

Efficacy of RADPAD protection drape in reducing radiation exposure in the catheterization laboratory-First Indian study.

BACKGROUND: Occupational radiation exposureis a growing problem due to increasing number and complexity of interventional procedures.The RADPAD is a lead-free sterile drape containing bismuth and barium that reduces scatter radiation during fluoroscopic procedures. We aimed to study the radiation exposure reduction to operators with the use of RADPAD and also measureradiation doses in different angiographic projections. METHODS: 65 randomly selected patients undergoing elective complex percutaneous coronary intervention (PCI) procedures from January 2017 to 2017 were randomized in a 1:1 pattern with or without the RADPAD. Primary endpoint was the ratio of operator received dose in mrem to total radiation in Gyat the end of the procedure which was designated ''Relative operator exposure'', with or without RADPAD. RESULTS: Despite similar fluoroscopy times (20.4 ±â€¯9.4 min with RADPAD vs. 19.4 ±â€¯9.2 min without RADPAD, P = 0.871) and total radiation dose (3.4 ±â€¯4.3 Gy with RADPAD vs. 2.3 ±â€¯1.4 Gy, P = 0.198), the relative operator exposure was significantly less with RADPAD (1.39 ±â€¯0.95) as compared to no RADPAD group (2.27 ±â€¯1.4) (p = 0.004) amounting to a 39% reduction. Additionally mean radiation dose per shoot of recorded Left anterior oblique (LAO) oriented projections was 34.4 ±â€¯15.7mGyvs 24.9 ±â€¯12.9 mGy for a non LAO oriented projection. (p < 0.001). CONCLUSION: RADPAD significantly reduces radiation exposure to the primary operator during prolonged complex PCI procedures. Further, amongst all views, LAO views have significantly higher emitted radiation as compared to Non LAO views and need more radiation protection.

[Ligamentous lesions and instability of the finger joints]. / Ligamentäre Verletzungen und Bandinstabilitäten der Fingergelenke.

Joint capsule and ligamentous lesions are common injuries of the upper extremities. Athletes are particularly inclined to suffer from these injuries. Clinical and radiological examinations are the cornerstone of an adequate treatment. Ultrasound-based diagnostics as a non-invasive and dynamic investigation method are gaining increasing relevance based on the development of high resolution probes. A correct interpretation of the findings is only feasible with a comprehensive knowledge of the anatomy. The most important goal is stability as a prerequisite for early active and passive motion with unrestricted range of motion.

Anterior laxity and patient-reported outcomes 7 years after ACL reconstruction with a fresh-frozen tibialis allograft.

PURPOSE: After reconstructing a torn ACL with a soft tissue allograft, the long-term healing process of graft maturation following the short-term healing process of graft incorporation into the bone tunnels might lead to recurring instability and concomitant decreases in the activity level, function, and patient satisfaction. Relying on roentgen stereophotogrammetric analysis (RSA), the primary purpose was to determine whether anterior laxity increased and whether patient-reported outcomes declined between 1 and 7 years for a particular graft construct, surgical technique, and rehabilitation programme. METHODS: Eighteen of 19 patients, who participated in an earlier RSA study which extended to 1 year after the surgical procedure, were contacted 7 years after the surgical procedure. An examiner, different from the treating surgeon, measured anterior laxity under 150 N of anterior force using RSA in 16 patients and obtained outcome scores in 17 patients. One patient moved abroad and could not be contacted. One patient reinjured his reconstructed ACL and was excluded. RESULTS: The average increase in anterior laxity of 1.5 ± 2.1 mm between 1 and 7 years after surgery was not significant (p = 0.08), and the average increase in anterior laxity of 2.7 ± 2.3 mm between the day of surgery and 7 years was significant (p < 0.001). There were no significant declines in activity (median Tegner score, 6 at 1 year, 6 at 7 years), function (average Lysholm score, 94 at 1 year, 91 at 7 years), and subjective satisfaction (average International Knee Documentation Committee score, 90 at 1 year, 87 at 7 years) between 1 and 7 years after surgery. CONCLUSION: In demonstrating that the ACL graft construct remains functional in the long term, this study supports the use of a fresh-frozen tibialis allograft in patients with an average age of 37 years at the time of surgery when used in conjunction with a surgical technique which avoids roof and PCL impingement, uses slippage-resistant fixation devices, and allows brace-free, self-paced rehabilitation. LEVEL OF EVIDENCE: IV.