Comparison of Minced Cartilage Implantation with Autologous Chondrocyte Transplantation in an In Vitro Inflammation Model.

The current gold standard to treat large cartilage defects is autologous chondrocyte transplantation (ACT). As a new surgical method of cartilage regeneration, minced cartilage implantation (MCI) is increasingly coming into focus. The aim of this study is to investigate the influence of chondrogenesis between isolated and cultured chondrocytes compared to cartilage chips in a standardized inflammation model with the proinflammatory cytokine TNFα. Articular chondrocytes from bovine cartilage were cultured according to the ACT method to passage 3 and transferred to spheroid culture. At the same time, cartilage was fragmented (<1 mm3) to produce cartilage chips. TNFα (20 ng/mL) was supplemented to simulate an inflammatory process. TNFα had a stronger influence on the passaged chondrocytes compared to the non-passaged ones, affecting gene expression profiles differently between isolated chondrocytes and cartilage chips. MCI showed less susceptibility to TNFα, with reduced IL-6 release and less impact on inflammation markers. Biochemical and histological analyses supported these findings, showing a greater negative influence of TNFα on the passaged pellet cultures compared to the unpassaged cells and MCI constructs. This study demonstrated the negative influence of TNFα on chondrogenesis in a chondrocyte spheroid culture and cartilage fragment model. Passaged chondrocytes are more sensitive to cytokine influences compared to non-passaged cells and chondrons. This suggests that MCI may have superior regeneration potential in osteoarthritic conditions compared to ACT. Further investigations are necessary for the translation of these findings into clinical practice.

The German version of the Nottingham Clavicle Score is a reliable and valid patient-reported outcome measure to evaluate patients with clavicle and acromioclavicular pathologies.

PURPOSE: The Nottingham Clavicle Score (NCS) is a patient-reported outcome measure developed to evaluate treatment results of clavicle, acromioclavicular and sternoclavicular joint pathologies. Valid, reliable and user-friendly translations of outcome measure instruments are needed to allow comparisons of international results. The aim of this cross-sectional study was to translate and adapt the NCS into German and evaluate the psychometric properties of the German version. METHODS: The translation and cross-cultural adaptation of the NCS were completed using a 'translation-back translation" method and the final version was administered to 105 German-speaking patients. The psychometric properties of this version (NCS-G) were evaluated in terms of feasibility, reliability, validity and sensitivity to change. RESULTS: No major differences occurred between the NCS translations into German and back into English, and no content- or linguistic-related difficulties were reported. The Cronbach's alpha for the NCS-G was 0.885, showing optimal internal consistency. The Intraclass Correlation Coefficient for test-retest reliability was 0.907 (95% CI 0.844-0.945), with a standard error of measurement of 5.59 points and a minimal detectable change of 15.50 points. The NCS-G showed moderate to strong correlation with all other investigated scales (Spearman correlation coefficient: qDASH: ρ = - 0.751; OSS: ρ = 0.728; Imatani Score: ρ = 0.646; CMS: ρ = 0.621; VAS: ρ = - 0.709). Good sensitivity to change was confirmed by an effect size of 1.17 (95% CI 0.89-1.47) and a standardized response mean of 1.23 (95% CI 0.98-1.45). CONCLUSIONS: This study demonstrated that NCS-G is reliable, valid, reproducible and well accepted by patients, showing analogous psychometric properties to the original English version. LEVEL OF EVIDENCE: Level III.

Video Based Assessment of Treatment Urgency in Outpatient Orthopaedic and Trauma Patients - a Pilot Trial. / Videobasierte Einschätzung der Behandlungsdringlichkeit - eine Pilotstudie für ambulante Patienten in der Orthopädie und Unfallchirurgie.

INTRODUCTION: When consulting a specialist in orthopaedics and trauma surgery, personal assessment and manual clinical examination by the doctor on site are essential. Nevertheless, implementation of video consultation hours has been made legally easier in Germany. The present pilot study examines the possibility of video-based assessment of the urgency of treatment in outpatient orthopaedic and trauma patients. MATERIALS AND METHODS: Within an ex ante study design, 40 patients with an orthopaedic clinical picture for trauma surgery with elective, urgent or emergency indication were selected from consultation hours. A short questionnaire was filled in based on the information provided and a medical colleague simulated a movement sequence based on the patient information. After modification to the "red flags" and "yellow flags" established in spinal orthopaedics, nine short questions were recorded, which inquire about the urgency of a medical consultation. The video-based movement sequence is based on a 60 s long instruction video in which motor tests and movement sequences are demonstrated: Cervical spine movement in all levels, elevation of the upper extremity, test of the finger-floor distance when "bending forward over-bending", possibility of crouching from standing and getting up again, standing on heels and toes. RESULTS: In 91.1% (n = 328) of the cases, the diagnosis was associated with the same joint or the same pathological entity. In 37.5% (n = 135) of the cases an emergency indication was seen, in 10.8% (n = 39) of the cases an urgent indication and in 51.6% (n = 186) of the cases it was seen to offer an elective indication. 12.5% (n = 45) of the cases were evaluated as "false positives" with regard to an emergency or urgent presentation. This means that the test persons were classified as "emergency" or "urgent", although there was no preventable dangerous course or medical emergency. 18 cases (5%) were evaluated as "false negative". DISCUSSION: The screening questionnaire presented and the short video assessment are technically feasible and practicable method for the initial evaluation in video-based online medical consultation. In addition, the questionnaire presented in combination with the short video assessment was suitable as an instrument for assessing the urgency of the consultation and selecting preventable dangerous processes and acute emergencies. CONCLUSION: The questionnaire, in combination with the short video assessment, is a suitable method for the social distancing requirements during limited accessibility of the medical system. Nevertheless, a false negative rate of 5% is too high to implement the questionnaire presented into daily clinics without further optimisation.

Anatomic reconstruction of lateral ankle ligaments: is there an optimal graft option?

PURPOSE: Different graft options are available for the reconstruction of lateral ankle ligaments to treat chronic ankle instability (CAI), which fall in two categories: allografts and autografts. This study aims to provide an updated comparison of the clinical outcomes after stabilisation procedures using allografts and autografts, to correctly advise the clinician during the choice of the best material to be used for the reconstruction of the lateral ligamentous complex of the ankle. METHODS: A systematic review was performed to analyse the use of autografts and allografts for anatomic reconstruction of the lateral ligamentous complex of the ankle in CAI patients. The presence of a postoperative assessment through outcome measures with proofs of validation in the CAI population or patient's subjective evaluation on the treatment were necessary for inclusion. The quality of the included studies was assessed through the modified Coleman Methodology Score (mCMS). Relevant clinical outcome data were pooled to provide a synthetic description of the results in different groups or after different procedures. RESULTS: Twenty-nine studies (autograft: 19; allograft: 9; both procedures: 1) accounting for 930 procedures (autograft: 616; allograft: 314) were included. The average mCMS was 55.9 ± 10.5 points. The Karlsson-Peterson scale was the most frequently reported outcome scale, showing a cumulative average post- to preoperative difference of 31.9 points in the autograft group (n = 379, 33.8 months follow-up) and of 35.7 points in the allograft group (n = 227, 25.8 months follow-up). Patient satisfaction was good or excellent in 92.8% of autograft (n = 333, 65.2 months follow-up) and in 92.3% of allograft procedures (n = 153, 25.0 months follow-up). Return to activity after surgery and recurrence of instability were variably reported across the studies with no clear differences between allograft and autograft highlighted by these outcomes. CONCLUSIONS: The systematic analysis of validated CAI outcome measures and the patient's subjective satisfaction does not support a specific choice between autograft and allograft for the reconstruction of the ankle lateral ligamentous complex in CAI patients. Both types of grafts were associated to a postoperative Karlsson-Peterson score superior to 80 points and to a similar rate of patient's subjective satisfaction. LEVEL OF EVIDENCE: Level IV.

Economic Effects of the SARS-CoV-2 Pandemic in 2020. / Wirtschaftliche Auswirkungen der SARS-CoV-2-Pandemie im Jahr 2020.

INTRODUCTION: In 2020, the SARS-CoV-2 pandemic necessitated an adjustment to the care structure in all medical facilities in Germany. In this study we analysed the effects of the SARS-CoV-2 pandemic using the data from the annual balance sheet of a university department and maximum care provider for orthopaedics and trauma surgery. METHODS: Data analysis was performed on the clinic's performance parameters from 2019 and 2020. The analysis included 52943 outpatient and 7980 inpatient cases, together with the Case Mix Index (CMI), and the costs and revenues. RESULTS: As a result of the reduction in scheduled surgeries, the mean number of inpatients in March and April 2020 decreased by 10.4% (p = 0.004). Due to the focus on complex cases, the CMI increased by 29.5% (p = 0.007). The number of outpatient surgical procedures increased by 16.9% (n = 84). Rising costs of consumables due to the purchase of protective equipment were offset by a reduced need for orthopaedic implants. CONCLUSION: By reducing the number of elective inpatient surgical treatments, the focus was shifted to treating complex cases; this is reflected in the increased CMI. Due to internal compensation mechanisms, the clinic was able to conserve intensive care capacities while still achieving an increase in revenue.

The Impact of Lead Aprons on Posture of Orthopaedic Surgeons. / Der Einfluss von Röntgenschürzen auf die Körperhaltung von Orthopäden und Unfallchirurgen.

BACKGROUND: Surgeons working in orthopedics and trauma surgery are frequently exposed to repetitive actions and non-ergonomic positions in their operative activities with the regular use of lead aprons. Musculoskeletal complaints of the neck and back among surgeons are reported in the literature as up to 80%. In this study, the effects of lead aprons on the posture of surgeons are examined using videorasterstereography, foot pressure measurement and questionnaires. METHODOLOGY: All subjects (n = 31) were examined before and after exposure to wearing lead aprons during surgery using videorasterstereography and pedography. In addition, a survey with a separately created questionnaire and the Cornell Musculoskeletal Discomfort Questionnaire (CMDQ) was carried out. RESULTS: An average duration of lead apron use of 102.6 min showed an increase in forefoot load (p = 0.002) especially in the elderly subjects and thoracic kyphosis (p < 0.001) especially in the younger doctors with a significant lateral deviation (p = 0.006). In addition, the lateral deviation was shown to correlate with an increasing body size or a shorter period of employment (p = 0.008; r = 0.51/p = 0.026; r = - 0.44). Significantly fewer surgeons experienced back complaints on working days without lead apron use in the operating room compared to days in the OR (p = 0.011). CONCLUSION: The impact of wearing front covered lead aprons during operations in the field of orthopaedics and trauma surgery leads to more frequent back complaints, even among young and healthy doctors. Under an average duration of surgery of 102 min a temporary postural deviation occurs that can be demonstrated by means of videorasterstereography and foot pressure measurement. The subjects showed a shifted weight distribution on the forefoot, a gain in thoracic kyphosis and an increase in lateral deviation, which also correlated with an increasing height and shorter length of employment.

Is Prematurity a Protective Factor Against Developmental Dysplasia of the Hip? A Retrospective Analysis of 660 Newborns.

PURPOSE: In Middle Europe developmental dysplasia of the hip (DDH) has an incidence of up to 5.9 %. The rate of congenital hip dislocation as the worst complication of a growth disorder of the hip is between 1.5 % and 2.5 %. Among known risk factors of DDH are breech position, multiples, foot deformities and family history. The aim of this retrospective study was to investigate prematurity as a risk factor for developmental dysplasia of the hip (DDH). MATERIALS AND METHODS: The hips of 283 infants who were born before the 38th week of gestation or earlier, and those of 377 infants who were born after the 37th week of gestation, none of whom had other risk factors for DDH, were compared using the ultrasound technique according to Graf et al., within the first week after birth. Both hips of all infants were included in the study. RESULTS: Surprisingly, the difference in alpha angles between the two groups was statistically extremely significant, favoring the preterm infants. Moreover, we found a physiological curve of alpha angle development with a peak after the 31st week of gestation. The incidence of pathological dysplasia was not significantly different in the two groups. CONCLUSION: Our results suggest that prematurity is not a predisposing factor for DDH, but rather is protective for hip development.

sCD28, sCD80, sCTLA-4, and sBTLA Are Promising Markers in Diagnostic and Therapeutic Approaches for Aseptic Loosening and Periprosthetic Joint Infection.

Aseptic prosthetic loosening and periprosthetic joint infections (PJI) are among the most frequent complications after total knee/hip joint arthroplasty (TJA). Current research efforts focus on understanding the involvement of the immune system in these frequent complications. Different immune cell types have already been implicated in aseptic prosthetic loosening and PJI. The aim of this study was to systematically analyze aspirates from knee and hip joints, evaluating the qualitative and quantitative composition of soluble immunoregulatory markers, with a focus on co-inhibitory and co-stimulatory markers. It has been shown that these molecules play important roles in immune regulation in cancer and chronic infectious diseases, but they have not been investigated in the context of joint replacement. For this purpose, aspirates from control joints (i.e., native joints without implanted prostheses), joints with TJA (no signs of infection or aseptic loosening), joints with aseptic implant failure (AIF; i.e., aseptic loosening), and joints with PJI were collected. Fourteen soluble immunoregulatory markers were assessed using bead-based multiplex assays. In this study, it could be shown that the concentrations of the analyzed immunoregulatory molecules vary between control, TJA, AIF, and PJI joints. Comparing TJA patients to CO patients, sCD80 was significantly elevated. The marker sBTLA was significantly elevated in AIF joints compared to TJA joints. In addition, a significant difference for eight markers could be shown when comparing the AIF and CO groups (sCD27, sCTLA-4, sCD137, sCD80, sCD28, sTIM-3, sPD-1, sBTLA). A significant difference was also reached for nine soluble markers when the PJI and CO groups were compared (sLAG-3, sCTLA-4, sCD27, sCD80, sCD28, sTIM-3, sPD-1, IDO, sBTLA). In summary, the analyzed immunoregulatory markers could be useful for diagnostic purposes as well as to develop new therapeutic approaches for AIF and PJI.

In-Depth Characterization of Stromal Cells within the Tumor Microenvironment Yields Novel Therapeutic Targets.

Cells within the tumor stroma are essential for tumor progression. In particular, cancer-associated fibroblasts (CAF) and CAF precursor cells (resident fibroblasts and mesenchymal stromal cells) are responsible for the formation of the extracellular matrix in tumor tissue. Consequently, CAFs directly and indirectly mediate inflammation, metastasis, immunomodulation, angiogenesis, and the development of tumor chemoresistance, which is orchestrated by complex intercellular cytokine-mediated crosstalk. CAFs represent a strategic target in antitumor therapy but their heterogeneity hinders effective treatment regimes. In-depth understanding of CAF subpopulations and knowledge of specific functions in tumor progression will ultimately result in more specific and effective cancer treatments. This review provides a detailed description of CAFs and CAF precursor cells and summarizes possible treatment strategies as well as molecular targets of these cells in antitumor therapies.

The Performance of a Dithiothreitol-Based Diagnostic System in Diagnosing Periprosthetic Joint Infection Compared to Sonication Fluid Cultures and Tissue Biopsies.

PURPOSE: The aim of this study was to evaluate the performance of a commercially available dithiothreitol (DTT) kit for routine use in diagnosing periprosthetic joint infections (PJIs) in comparison to conventional microbiological tissue specimens and sonication procedures in a maximal care hospital. METHODS: We applied the DTT system in 40 consecutive cases of revision arthroplasty (23 PJIs and 17 aseptic revisions), with an exchange or a removal of components. The hardware components were split between the DTT system and the conventional sonication procedure. At least three tissue biopsies and a joint fluid specimen were sent for microbiological and histopathological analysis. Data was analysed retrospectively to compare between the different methods. RESULTS: Cultures of the DTT fluid showed a sensitivity of 65% and specificity of 100%, as referenced to conventional microbiological cultures. Sonication had better sensitivity (75%) but lower specificity (85%). The categorical agreement of DTT cultures compared to sonication fluid cultures was 78% (31/40). Neither pathogen type, infection duration nor antibiotic pretreatment influenced the accuracy of the DTT, but a low pH in the DTT seemed to be associated with false-negative results. CONCLUSION: DTT was inferior in sensitivity when diagnosing PJIs compared to sonication fluid cultures and tissue biopsies. A low pH in the DTT fluid correlated with false-negative results. Nevertheless, the closed system of the DTT kit avoids contamination and false-positive results, and DTT can be an alternative where sonication is not available.

The Value of Video Rasterstereography in the Detection of Alterations in Posture as a Marker of Pain Relief after Targeted Infiltrations of the Lumbar Spine.

BACKGROUND: Targeted infiltrations to the lumbar spine are used to identify the correct scope for surgery in patients with chronic lumbar back pain (CLBP) and multi-segmental pathologies, where radiologic imaging and clinical presentation do not match. Conclusions from that method have so far been based on individual statements of pain relief. The main principle for the infiltrations is the assumption that by locally administering an analgesic agent to possible surgical target areas, the effect of surgery can be temporarily simulated. The aim was to investigate the use of rasterstereographic posture measurements to substantiate reported pain reduction after infiltrations. METHODS: In this case-control study (Level II), rasterstereography was performed on 57 patients and 28 reference subjects to evaluate changes in posture during 1 week of injections under fluoroscopic guidance and correlated with changes in the Numeric Pain Rating Scale (NRS). Statistical analysis was performed with SPSS (α = .05, two-sided) and presented in the form of box, scatter, and Bland-Altman plots. RESULTS AND CONCLUSION: The CLBP patients' trunk inclination (median 6°) and absolute lateral tilt were significantly increased (p < .01 each) compared to the reference group. No significant difference was observed for trunk length, kyphotic/lordotic angle, or lateral deviation. During infiltration, no significant difference in posture could be observed. A subgroup analysis of patients reporting the highest pain improvement indicated no significant difference. No correlation was observed with pain improvement reported by the patients during injections. Subsequent rasterstereography does not seem to be able to verify results of injections in the diagnostics of lumbar spine pathologies, as patients' reported pain relief does not correlate with a relevant alteration in posture. The short-term effect of the targeted infiltrations may not suffice to change false posture being developed over years.

[Outcome after plate stabilization of symphyseal diastasis]. / Ergebnisse nach Plattenstabilisierung der Symphysensprengung.

BACKGROUND: Separation of the pubic symphysis with corresponding diastasis can be stabilized by symphyseal plating. OBJECTIVE: Which pelvic injuries are stabilized with symphyseal plating and what is their outcome? MATERIAL AND METHODS: A retrospective evaluation of 64 patients who underwent symphyseal plating over a period of 24 months was conducted. RESULTS: Of the patients 56 were male and 8 female with a mean age of 44 years (SD ± 17 years). The main cause of the pelvic injuries were traffic accidents. The distribution according to the AO fracture classification was 14â€¯× B1, 10â€¯× B2, 5â€¯× B3, 23â€¯× C1, 9â€¯× C2 and 3â€¯× C3 injuries. The distribution according to the Young and Burgess classification showed 9â€¯× APC I, 18â€¯× APC II, 13â€¯× APC III, 9â€¯× LC I, 3â€¯× LC II, 2â€¯× LC III and 10â€¯× VS injuries. The mean Injury Severity Score (ISS) was 32 (SD ± 17) and the mean inpatient stay was 29 days (SD ± 16 days; positive correlation p ≤ 0.001). Radiological implant loosening occurred in 52 patients. 14 patients required treatment for severe complications. The leading reason for revision surgery was implant failure (n = 8). CONCLUSION: These observations suggest that radiological signs of implant loosening are commonly observed but rarely the reason for revision surgery. Complete implant failures, however; occur mainly within the first postoperative weeks and require early revision. A timely clarification by additional X-ray imaging should be carried out if this is suspected.

A Systematic Review on the Value of Infrared Thermography in the Early Detection of Periprosthetic Joint Infections. / Infrarotthermografische Untersuchungen nach endoprothetischem Gelenkersatz ­ ein systematisches Review.

BACKGROUND: Variations in the temperature of body and skin are symptoms of many pathological changes. Although joint replacement surgery of hip and knee has been very successful in recent decades, periprosthetic infection is a growing problem and the number one reason for revision. While many studies have investigated changes in blood levels, investigation of temperature has not been performed on a regular basis. The objective of this work is to determine whether reference literature exists for the infrared thermographic examination in knee and hip arthroplasty and if reference values can be derived for the methodology or if there is a peri- and postoperative benefit. MATERIAL UND METHODS: By means of a systematic online database search and based on the Cochrane, PICOT and PRISMA guidelines, this systematic review retrieved 254 studies. All publications with thermographic examination in arthroplasty of the hip and knee were imbedded. 249 studies were excluded due to the defined inclusion and exclusion criteria and five studies with 251 patients have finally been included in the evaluation process. This was followed by an analysis and discussion of the methodology. RESULTS AND CONCLUSION: Infrared thermography is a useful tool in the perioperative care of patients after arthroplasty of the knee and hip joint. The technology is portable, easy to use and non-invasive. Based only on these few publications, values can be derived, which provide a guidance for the thermographic aftercare in arthroplasty surgery.

Using inpatient gradual diagnostics to identify the treatment strategy for lumbar back pain-Can treadmill gait analysis objectify the patients' declaration of pain relief?

BACKGROUND: Patients with chronic lumbar back pain (CLBP) often present with an altered gait profile, which is a crucial element of good functioning in everyday life. In patients with multisegmental spinal pathologies and incongruity between radiologic imaging and clinical presentation, inpatient gradual diagnostics (IGD) is performed to determine the precise origin of the disabling pain. The underlying principle of IGD is the assumption that by locally administering an analgesic and anti-inflammatory agent to possible surgical target areas, the surgical effect can be temporarily simulated. The conclusions drawn from IGD are, however, mostly based on the patients' subjective feedback about pain relief. RESEARCH QUESTION: The aim of this study was to evaluate whether reported pain relief during IGD can be objectified by gait analysis. We hypothesized that patients with greater pain relief during IGD would show greater improvement in their pathologic gait and stance. METHODS: Treadmill gait and stance analyses were prospectively performed on CLBP patients before and after a one-week IGD. Self-report measures included the numeric pain rating scale (NRS) and the Oswestry Disability Index (ODI). RESULTS AND SIGNIFICANCE: Compared with a reference group (n = 28), IGD patients (n = 57) at admission showed reduced velocity, cadence, step length, and swing phase (p < .01 each). Their stance phase was increased by 5% of the gait cycle, and a more asymmetrical total load distribution during stance was observed. No difference was seen in stride width or foot rotation. While many patients reported good pain relief during IGD, no correlation was observed between subjective improvement and treadmill measures. We can thus confirm a pathologic gait profile in patients with CLBP. Based on our findings, gait analysis would not yet seem suitable to objectify IGD results. The short time interval between admission and discharge may not suffice to change a pathological gait that has developed over years.

Evaluation of Patients' Posture and Gait Profile After Lumbar Fusion Surgery by Video Rasterstereography and Treadmill Gait Analysis.

This protocol provides guidance on how to perform high resolution video rasterstereography and treadmill gait analysis on patients after lumbar fusion surgery to obtain results about altered variables of gait and posture. These observed changes can then be correlated with the patient-reported outcome measure of pain relief. The rasterstereographic device projects lines of parallel light onto the surface of the tested subject's back. The deformation of these lines is recognized by the device. From these data, a special software then generates a 3-D profile based on the principle of triangulation. With an inaccuracy of only 0.2 mm it can measure changes in posture at very high precision. Gait and stance parameters are recorded using a treadmill equipped with an electric sensor mat that contains 10,200 miniature force sensors in the registering zone under the belt. Initial walking speed on the treadmill is 0.5 km/h. Speed is then gradually increased by increments of 0.1 km/h until each subject reaches his or her individual maximum well tolerable walking speed. At this speed, parameters are recorded during a 20 s measurement interval. Subjects are tested barefoot and without holding a handrail. Among various other parameters, stride width, step length, stance phase and foot rotation are measured. Both methods used reportedly have a high intra- and inter-observer reliability. The advantage of these highly accurate techniques is that they offer an objective and very detailed perspective on changes in the patient's posture and gait. Due to the amount of data generated, these techniques are, however, not so much suitable for everyday routine use, but rather interesting to scientifically evaluate long term alterations in posture and gait in patients like for example after lumbar fusion surgery.

Soft Tissue Sarcoma - a Current Review of the Diagnostic and Treatment Strategies. / Weichteilsarkome ­ eine Übersicht aktueller evidenzbasierter Behandlungskonzepte.

Soft tissue sarcomas are a heterogeneous group of neoplasias that due to their often clinically silent appearance often remain undetected or experience delayed treatment. Especially soft tissue swelling is often misinterpreted by patients and doctors and trivialized or verified with an incorrect biopsy technique. The hereby evoked complications for the patients are serious and may be reduced by simply following the available guidelines. The treatment of soft tissue sarcomas requires a close interdisciplinary coordination between specialists in tumor orthopedics, oncology, radiology, pathology and radiotherapy. On the basis of a selective literature review, the following article points out the current evidence on the treatment and illustrates a treatment algorithm.

Laser-based Techniques for Microcirculatory Assessment in Orthopedics and Trauma Surgery: Past, Present, and Future.

: Microcirculatory integrity and proper function are the cornerstones to tissue nourishment and viability. In the clinical environment extended immobility, injuries, and inflammatory reactions demand local microcirculatory adaption to provide adequate supply. Assessment of endothelial adjustment capability and microcirculatory perfusion status, as direct or surrogate markers of disease, are therefore of uttermost interest to the treating physician. Given the simple, noninvasive, nonradiating nature of laser-based techniques for bedside or intraoperative microcirculatory perfusion assessment, this article's objective is to present a comprehensive overview of available techniques, their technological aspects, and current application. Advantages of individual methods are pointed out and compared with each other. The areas of medical utilization relevant to orthopedics and trauma surgery are exemplified and their available evidence elaborated. A particular focus is put on laser speckle contrast imaging, with its current and future influence on medical practice.

3-D Optics for Thoracoscopic Vertebral Body Replacement - Essential Technical Progress or Just Nice to Have? / Die dreidimensionale Optik für den thorakoskopischen ventralen Wirbelkörperersatz ­ notwendiger Fortschritt oder nur "nice to have"?

BACKGROUND: Three-dimensional (3-D) endoscopic optics use 2 cameras to simulate the different perspectives of the right and left eye, creating the illusion of spatial depth. Optimised orientation as well as improved hand-eye coordination compared to 2-D-optics could be proven in standardised test setups (black box) and in laparoscopic use. This retrospective study examines whether these results can also be applied to thoracoscopic vertebral body replacement at the thoracolumbar junction. HYPOTHESES: 1. Ventral vertebral body replacement using 3-D-thoracoscopy results in a shorter operation time than with 2-D-thoracoscopy. 2. Perioperative blood loss is less, due to better spatial orientation (faster haemostasis) and reduced tissue laceration. MATERIAL AND METHODS: 29 patients met the inclusion criteria of this retrospective study. Between 08 - 2012 and 08 - 2017, all of these received ventral thoracoscopic vertebral replacement at the thoracolumbar junction (Th11 to L2). Patients with additional anterior procedures (e.g. anterolateral plate) were excluded. Perioperative data such as blood loss, duration of surgery and length of hospital stay were analysed. Conventional 2-D-optics were used in n = 14 patients and 3-D-optics in 15 patients. Aesculap EinsteinVision® 2.0 was used as the 3-D-optics. Statistical significance was calculated using Student's t-test. RESULTS: The most common diagnosis was a L1 fracture (n = 18, 62%). Mean OR time was 24 minutes shorter in the 3-D group (149 ± 29, 107 - 198 min) than in the 2-D group (173 ± 39, 125 - 260 min), but this difference was not significant. Total perioperative blood loss in the 3-D group was significantly lower than in the 2-D group (**p = 0.043). Proportional intraoperative blood loss in the 3-D group was also lower (mean around 115 ml), but not significantly so. Significantly lower values were found for the delivery rate of the thoracic drainage in the 3-D group (248 vs. 560 ml, *p = 0.195). Inpatient stay with the 3-D group was on average 1.5 days (d) shorter (8.7 d for the 3-D group, 10.2 d for the 2-D group) but this difference was not significant (p = 0.27). CONCLUSION: Thoracoscopic-assisted vertebral body replacement at the thoracolumbar junction is a safe and reliable surgical procedure using conventional 2-D-optics or the new 3-D-optics. Both methods allow thoracoscopic vertebral body replacement in comparable operation times but in our study the 3-D group presented with significantly lower postoperative blood loss. Due to the small number of cases and because of the retrospective design, the present study is considered to be a pilot study only.

Using video rasterstereography and treadmill gait analysis as a tool for evaluating postoperative outcome after lumbar spinal fusion.

BACKGROUND: The rise in the number of patients with lumbar back pain has led to an increase in the number of spinal surgeries. To avoid unfavorable outcomes, high accuracy and reliability of indication for surgery are essential. This requires critical evaluation of postoperative outcomes with its two key dimensions pain and function. While imaging findings give details about the technical dimension of the intervention, they are prone to high inter-/intra-observer variability, with limited relation to functional outcomes. Pain improvement can be directly asked from patients or documented by questionnaires. There is abundant literature on postoperative function based on questionnaires, but quantifiable data such as gait or posture analysis are scarce. Highprecision measurement tools are available and easy to implement in a clinician's work routine. OBJECTIVE: This study evaluates whether lumbar fusion surgery changes gait and postural variables and how these changes are related to patients' descriptions of alterations in their levels of pain. METHODS: Back profiles and gait analyses were measured by video rasterstereography and treadmill gait analysis. Measurements were recorded before surgery, at discharge, after 3 months in a longitudinal (n = 30), and after 12 months in a cross-sectional group (n = 29). A reference group was formed (n = 28). The improvement on the Numeric Pain Rating Scale was documented and compared with changes in gait and posture. RESULTS: A significant reduction in kyphotic (52-43°, p = 0.014) and lordotic (28-11°, p < 0.001) angles was observed. The values again increased after 3 months, with a significant reduction in cadence (98-91 steps/min, p = 0.006). While improvements in pain were also obtained by surgery (p < 0.001), no clear correlation could be detected between 3-month alleviation in pain and changes in kyphotic/lordotic angle or cadence. CONCLUSIONS: Although both methods offer high-precision measurement, changes in gait and posture were not related with the patients' reported pain relief after lumbar fusion surgery.

When does intraoperative 3D-imaging play a role in transpedicular C2 screw placement?

INTRODUCTION: The stabilization of an atlantoaxial (C1-C2) instability is demanding due to a complex atlantoaxial anatomy with proximity to the spinal cord, a variable run of the vertebral artery (VA) and narrow C2 pedicles. We perfomed the Goel & Harms fusion in combination with an intraoperative 3D imaging to ensure correct screw placement in the C2 pedicle. We hypothesized, that narrow C2 pedicles lead to a higher malposition rate of screws by perforation of the pedicle wall. The purpose of this study was to describe a certain pedicle size, under which the perforation rate rises. PATIENTS AND METHODS: In this retrospective study, all patients (n=30) were operated in the Goel & Harms technique. The isthmus height and pedicle diameter of C2 were measured. The achieved screw position in C2 was evaluated according to Gertzbein & Robbin classification (GRGr). RESULTS: A statistically significant correlation was found between the pedicles size (isthmus height/pedicle diameter) and the achieved GRGr for the right (p=0.002/p=0.03) and left side (p=0.018/p=0.008). The ROC analysis yielded a Cut Off value for the pedicle size to distinguish between an intact or perforated pedicle wall (GRGr 1 or ≥2). The Cut-Off value was identified for the isthmus height (right 6.1mm, left 5.4mm) and for the pedicle diameter (6.6mm both sides). CONCLUSION: The hypothesis, that narrow pedicles lead to a higher perforation rate of the pedicle wall, can be accepted. Pedicles of <6.6mm turned out to be a risk factor for a perforation of the pedicle wall (GRGr 2 or higher). Intraoperative 3D imaging is a feasible tool to confirm optimal screw position, which becomes even more important in cases with thin pedicles. The rising risk of VA injury in these cases support the additional use of navigation.