The authors have no acknowledgements.

Full approvals from the Department of Orthopaedic Surgery at the University of Tuebingen and the Ethics Committee at the University Hospital Tuebingen were obtained before the commencement of the study. Written informed consent was received from all subjects before their participation.
1. Patient Recruiting and Preparation
<ol>
	<li>Recruit a subject, aged more than 18 years, who suffers from lumbar back pain and degenerative disc disease.
	<ol>
		<li>Gather all relevant data as back pain related patient history, results from magnetic resonance imaging, current pain medication and history of physiotherapy.</li>
		<li>Perform an orthopedic physical examination to identify the origin of the lumbar back pain looking for tender pressure points, test lateral flexion and trunk inclination and extension, and perform the straight leg raise. For differential diagnosis also test the hip joint for example for flexion, extension and rotation. 
		NOTE: 30 subjects and 28 reference subjects were used for the original study.</li>
	</ol>
	</li>
	<li>Rule out that the subject has a neurologic deficit of the lower limbs that requires immediate surgery by physical examination of each of the key muscles. 
	NOTE: A deficit in the sensorimotor system of the lower limb of less than grade 3/5 (Janda&#39;s classification) should not be included in this study.</li>
	<li>Ensure that the subject presents with normal walking ability and does not show any acute neoplastic or infectious pathology of the spine. 
	NOTE: The neoplastic or infectious pathology of the spine will be visible in the magnetic resonance imaging.</li>
	<li>Schedule the subject for spinal surgery.</li>
	<li>Ask all subjects to sign an informed consent for participating in the study.</li>
	<li>Schedule measurement dates for the following experimental setup (see 1.7, 1.8, 1.9., 1.10.) with the subject.</li>
	<li>Perform the first measurement one day prior to surgery.</li>
	<li>Perform the second measurement approximately seven days after surgery, when walking on ward-level is regained.</li>
	<li>Schedule and perform the third measurement three-months postoperatively.</li>
	<li>Schedule and perform the fourth measurement one-year postoperatively. 
	NOTE: During each examination ask the subject to complete the Oswestry Disability Index (ODI) 34 questionnaire and to indicate their usual value on the Numeric Pain Rating Scale (NRS) 35.</li>
	<li>Perform the gait and posture analysis with the subject on each visit following the subsequent instructions under section 2 of the protocol.</li>
</ol>
2. Experimental Design
<ol>
	<li>Questionnaires
	<ol>
		<li>Ask the subject to complete the Oswestry Disability Index (ODI) questionnaire and to indicate his or her usual value on the Numeric Pain Rating Scale (NRS).</li>
	</ol>
	</li>
	<li>Rasterstereographic analysis
	<ol>
		<li>Implement the measurement setup.
		<ol>
			<li>Use a device based on the principle of optical stereographic measuring that allows the detection of the specific anatomical landmark&#39;s vertebra prominens, the two lumbar dimples, and the sacrum point of the rima ani.</li>
			<li>Use an apparatus that estimates spine configuration on the Moir&#233; principle using a projector that projects a grid of light lines on the patient&#39;s back and contains a light-optical scanning camera. 
			&#8203;NOTE: Based on the principles of triangulation, the software analyzes the projected lines and generates a 3-D model of the patients&#39; surface (7,500 points).</li>
			<li>Build the measurement system with two main modules: the light projector unit that emits the projections of parallel lines and captures the reflections with a camera (15 Hz) and a personal computer with the manufacturer&#39;s analysis-software installed.</li>
			<li>Additionally, hang up a 2.5 m x 2 m piece of plain black cloth or similar that entirely covers the background of the image taken to improve the contrast.</li>
		</ol>
		</li>
		<li>Begin the measurement-process by asking the subject to undress from head down to the waist to expose all four needed anatomical landmarks: the neck with the vertebra prominens, the two lumbar dimples, and the sacrum point as the cranial end of the rima ani.</li>
		<li>Make sure that especially the caudal landmarks are also visible. This may require that the subject opens the trousers and lowers them a little.</li>
		<li>Let the subject stand freely and barefoot in a relaxed standard anatomical position with the feet shoulder-wide apart.</li>
		<li>Position the subject&#39;s front facing towards the wall with the black background while his or her back is targeted to the camera device.
		<ol>
			<li>Measure the distance from the subject&#39;s back surface to the camera device with a measuring tape, as it needs to be at 200 cm during all measurements.</li>
		</ol>
		</li>
		<li>Begin the measurement by clicking the button for the software&#39;s automatic landmark detection on screen while the subject stands freely, barefoot in a relaxed standard anatomical position with the feet shoulder-wide apart.
		<ol>
			<li>In case of a scanning error manually re-adjust the landmarks position according to the manufacturer&#39;s instructions provided with the software, so that they match their actual anatomic position (see step 2.2.2).</li>
		</ol>
		</li>
		<li>Set the system to a measurement time of 30 s. Due to the 15 Hz rate of the camera device about 450 images will be captured.</li>
		<li>Click Generate on the software panel and wait for the results. The software will calculate the average terminal values needed for further analysis.</li>
		<li>Let the subject rest for 120 s and subsequently step on the treadmill device.</li>
	</ol>
	</li>
</ol>
3. Treadmill Gait Analysis and (Optional) Plantar Pressure Measurements
<ol>
	<li>Use an instrumented treadmill with an integrated system containing capacitive pressure sensors under the belt to register gait parameters such as stride width, step length, stance phase and foot rotation.
	<ol>
		<li>Make sure to use a measuring system that contains of 10,200 miniature 0.85 cm x 0.85 cm capacitive pressure sensors on a mat of 150 cm x 50 cm, registering the exerted force at a rate of 120 Hz and which has a spatial resolution of the mat of 1.4 sensors/cm2.</li>
	</ol>
	</li>
	<li>At first, connect the treadmill and video camera to a commercial personal computer using the manufacturer&#39;s measurement software.</li>
	<li>Ask the subject to stand on the treadmill barefoot and with the pants rolled up to the knees.</li>
	<li>Attach a safety plug to the subject&#39;s shirt. 
	NOTE: The safety belt ensures measurement safety by an automatic shutdown of the treadmill, if the subject stumbles or is pushed too far back by the belt. In addition, the treadmill can be shut off via an emergency stop button or a cord.</li>
	<li>Use two lateral rail bars attached to the sides of the treadmill, to prevent the patient from falling off the treadmill in case of stumbling.</li>
	<li>Set the slope of the treadmill at 0% during the entire measurement. 
	NOTE: If necessary, the slope of the treadmill used in this study can be adjusted in a range from -2% to +15% in 0.5% increments, to simulate up-hill walking.</li>
	<li>To register the total load distribution on each foot, ask the subject to stand freely on the treadmill sensors thrice for 10 s. Then calculate the mean value of these three measurements.</li>
	<li>In the next step, when the treadmill is turned on, ask the subject to walk with normal gait and, as far as possible, not to hold on to the handrails. 
	NOTE: Walking on the treadmill without holding the handrail is recommended to obtain more dependable results and achieve higher reliability.</li>
	<li>Furthermore, advise the subject to walk between two adhesive tape markers you accurately attached beforehand on the surface of the treadmill to define the limits of the integrated sensor mat.</li>
	<li>After starting the treadmill, increase the speed in small increments of 0.1 km/h starting from 0.5 km/h until the subject&#39;s individual maximum well tolerable walking speed is reached. Ask the subject during the increase how he or she feels comfortable walking. 
	NOTE: The maximum well tolerable walking speed is reached when the subject has reached the highest walking speed with which he or she feels still comfortable walking. The belt speed can be upregulated in 0.1 km/h increments to a maximum speed of 22 km/h which thus even allows running measurements. The minimum speed of the treadmill is 0.5 km/h.</li>
	<li>For every subject measure two trials with a duration of 20 s. Let the subject rest for 60 s between the trials. 
	NOTE: The trial speed is specified by the individual walking speed determined in step 3.10.</li>
	<li>Film the subject&#39;s gait at the same time with a video camera from behind to allow visual correlation between the actual gait profile and the assessed parameters.</li>
	<li>Print the results displayed as a report through the software&#39;s interface at the end of the measurement. 
	NOTE: To further quantify foot pressure distribution during gait, the development of a software tool to subdivide the foot into different regions is necessary. For each region of interest pressures are registered from heel strike to toe-off during each gait cycle in N/cm&#178;. Eight distinct regions are defined: hindfoot, midfoot, first metatarsal head, second/third metatarsal head, fourth/fifth metatarsal head, hallux, second/third toe and fourth/fifth toe.</li>
</ol>
4. Experimental Design - Statistical Analysis
<ol>
	<li>Analyze the data obtained in step 2.2.8 and 3.13 using commercially available statistical software (Table of Materials). Import the data to the software by clicking Import.
	<ol>
		<li>Assess normality for the data obtained in step 2.2.8 and 3.13 by using histograms, the Shapiro-Wilk or Kolmogorov-Smirnoff test depending on the sample-size, and equality of variances by using the Levene test.</li>
		<li>Present data as mean (standard deviation) or median (minimum-maximum), depending on normality.</li>
		<li>Present categorical variables as relative or absolute frequencies.</li>
		<li>For treadmill variables organize each patient&#39;s bilateral data into major and minor values and calculate their absolute differences as a parameter for gait symmetry.</li>
		<li>For demographic characteristics use the Kruskal-Wallis test, chi-squared test, Friedman test, Wilcoxon test, and Tukey test, depending on normality.</li>
		<li>Calculate correlations between the measurement changes and changes in the patient-reported outcome measures between different time-points using Kendall&#39;s tau.</li>
		<li>Calculate NRS values as a percent of the initial value.
		<ol>
			<li>When grouping improvement on the Numeric Pain Rating Scale (NRS) ordinally, consider &#62;75% an excellent, 30-74% a moderate, and &#60;30% as no improvement. 
			NOTE: Since it is impossible to distinguish those patients with actual pain improvement &#60;30% accompanied by also functional improvement from those with improvement just due to a placebo effect (which can reach up to 30% improvement) where we would not expect functional changes, we classified this group for study purposes as &#34;no improvement&#34;35,36.</li>
		</ol>
		</li>
		<li>Interpret the Oswestry Disability Index (ODI) according the questionnaire&#39;s instructions.
		<ol>
			<li>Interpretation of the ODI: For each section, the total possible score is five. After all of the ten sections are completed by the patient, calculate the score as follows. Divide the selected total score by the total possible score (50) multiplied by 100 to obtain the final score in percent. For each section that is missed or not applicable the total score by which to divide is lowered by five. Interpretation of the final score: 0-20%: minimal disability, 21-40%: moderate disability, 41-60%: severe disability, 61-80%: crippled, 81-100%: exaggerating patient or bed-bound</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>

The authors have nothing to disclose.

Perioperative surgical outcome-monitoring is a field that is subjectively shaped. First it is affected by the surgeon&#39;s experience and secondly by the patient&#39;s subjective perception registered by for example questionnaires which also reflect his or her psychological distress and illness behavior. Our presented procedure offers an approach that objectifies crucial parameters regarding functional outcome. The methodical setup presented in this manuscript allows high precision measurements of changes in posture and gait after lumbar surgery18,37,38,39,40, but it can also be applied for other surgical interventions of the musculoskeletal system.
The investigator has to be aware of some method-related pitfalls. The rasterstereographic analysis of the back profile is highly dependent on the precise selection of the anatomical landmarks. If chosen imprecisely, measurement and data calculation will be incorrect as well. In addition, the subject&#39;s back must be completely undressed. Even wires of a bra or long scalp hair could disturb the scanning process. As gait measurements are susceptible to limping as a result of a painful hip, knee or ankle joint, the tested subjects need to be well examined before inclusion in the study and also before each follow-up visit to ensure the results are relevant and in correlation to the alterations of the spine. Since both methods have a high intra- and interobserver reliability21,24,41,42, their use in every-day routine can be easily implemented. However, combining both measurement-techniques might make it difficult to keep track of the abundance of data and to interpret these findings in a justifiable time.
One limitation of the technique of back surface measurement in general is that, to date, the data in the literature mostly refer to radiologic parameters obtained from X-rays to interpret postoperative outcome24. Since &#8212; due to modality-specific limitations &#8212; the definition of parameters used to describe posture differs between rasterstereography and X-rays (for example thoracic angle: rasterstereography thoracic vertebrae 1 to 12, x-ray thoracic vertebrae 4 to 12) it is not yet possible to derive conclusions from absolute values obtained by rasterstereographic analysis. It is rather their changes in the perioperative course that are of interest. Presently this tool is thus best suited for longitudinal analyses.
Other objectifiable data, such as CT (computed tomography imaging) or MRI (magnetic resonance imaging), can help to technically evaluate postoperative outcome, but they only illustrate static anatomical details. In contrast to the non-invasive and radiation-free measurement techniques described in this protocol, these imaging techniques are not able to take function into consideration8,9,10.
Interestingly the changes for gait and posture in our study were not always related with the patients&#39; levels of pain. It thus appears that the postoperative dimension of function is not strictly associated with pain experience. The observed functional results are thus to be considered not contradictory but rather complementary to the patient related outcome measures. These measurements hence offer an additional dimension to critically evaluate postoperative outcome.
The evaluation of gait and posture is still a highly dynamic research field. We are confident that providing data about perioperative development of such functional parameters will improve our understanding of these conditions. In the long run, this may also help to further improve our surgical outcomes.
It is, therefore, important to apply the technique described in detail in this protocol and video on a broader scale to obtain more data about the functional parameters posture and gait in the perioperative course of musculoskeletal surgery.

This protocol provides instructions on how to objectively perform a functional posture and gait analysis of patients after lumbar spinal fusion surgery in contrast to subjective evaluation by the examiner or patient reported questionnaires. The setup consists of a high-resolution video rasterstereography for posture analysis, and a pressure-sensor equipped treadmill setup for gait analysis. Results obtained by these techniques from patients after lumbar fusion surgery are compared with subjectively reported pain relief.
Even if spinal surgery techniques and outcomes have vastly improved over the past years, the increase in procedures performed1,2 also leads to a rise in absolute numbers of patients dissatisfied with their individual postoperative results. For surgeons, it is thus crucial to identify those patients who will most likely benefit from surgery. The development of this skill is closely associated with the constant postoperative outcome evaluation and reevaluation of the initial indication for surgery.
To date, the postoperative outcome is mostly judged on subjective patient-reported levels of pain and function by questionnaires3,4,5. These questionnaires are, however, always subjectively affected and not only influenced by the objective physical abnormality but also by the patient&#39;s attitudes and beliefs, psychological distress, and illness behavior. Interestingly, even findings in X-ray, computed tomography or magnetic resonance imaging are prone to high inter- and intra-observer variability6,7,8,9,10. The additionally radiologic imaging, however, only offers a static technical evaluation of the surgery. There is a clear lack in means to objectively evaluate the functional outcome after spinal surgery.
A patient&#39;s posture and gait are generally supposed to be linked to the perceived level of pain and also to the overall quality of life11,12. Therefore, function can be considered one of the most important elements of postoperative outcome. The overall functional satisfaction of the patient seems to be associated with spinal alignment, kyphosis, lordosis and vertebral rotation13,14,15. As lumbar fusion surgery tries to restore the anatomical curvature of the spine and therefore to balance the muscles, the adaptation of posture is expected16. Restored lumbar lordosis is complementary with pain relief and thus result in the ability to walk painless.
The technique of back surface analysis goes back to the work of Takasaki and Meadows et al., as well as Drerup et al. from the late 1970s and 80s17,18,19,20,21. Based on the principle of triangulation, this technique presents a measurement inaccuracy of only 0.2 mm&#160;22. The technique is widely used and tested for the radiation free diagnosis and follow-up of patient with scoliosis23,24. In the context of evaluation of scoliosis patients, the setup showed good validity and an excellent intra- and interrater reliability25. An even more functional view on the patient offers the analysis of gait. A common technique to register the distinct parameters used to describe a patient&#39;s gait is a treadmill experimental setup. Thus stride width, step length, stance phase and foot rotation as well as pressure distribution for each foot can be measured at a very high precision26,27,28,29,30,31. Whereas patients with low back pain seem to use strategies to reduce the impact on the lumbar spine while walking, the treadmill setup offers the advantage to measure a patient&#39;s walk while keeping track of every single step32.
The hypothesis is that lumbar fusion surgery changes pathologic patterns in gait or posture and that these changes are in correlation with the detectable alleviation in the patient-reported outcome measure i.e., level of pain. The expected changes can be measured with video rasterstereography and treadmill gait analysis. The additional information about posture and gait can thus be compared with the overall functional status and satisfaction14,15,33.

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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&#39;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&#39;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.

The representative results shown in this protocol come from a previous publication that has been published elsewhere26.
Rasterstereographic analysis 
The results of perioperative rasterstereographic analysis of patients who did suffer from chronic lumbar back pain and who were treated with lumbar fusion surgery (n = 59) showed no significant changes in trunk length at the 3 month follow-up in comparison to the preoperative measurements (459 (33) - 448 (40) mm; p = 0.313; Tukey test) (Figure 1A). We however noted a signi&#64257;cantly reduced kyphotic angle (vertebra prominens (VP) - thoracic spine vertebrae 12 (Th12), from 52&#176; to 43&#176;; p = 0.014; Tukey test) and lordotic angle (Th12 - dimple medium (DM), from 28&#176; to 11&#176;; p &#60; 0.001; Tukey test) at the &#64257;rst post-operative measurement when compared to the preoperative values (Figure 1B). No differences for the measurements of trunk inclination or lateral tilt were detected at any time point (Figure 1C, D).
Gait and stance analysis 
The treadmill gait measurements of the same patient cohort (n = 59) showed a significant reduction in cadence in the course from preoperatively to 3 months postoperatively (pre-OP to 7-days postoperatively: 98 (57-132) - 94 (43-119) steps/minute, p = 0.004; 3-months postoperatively: 91 (54-117) steps/minute, p = 0.006, Wilcoxon-test) (Figure 2A). Over the three postoperative months significant changes were detected for most spatiotemporal parameters (swing phase p = 0.01; stance phase p &#60; 0.001; foot rotation p = 0.001). However, no significant improvements were seen for the symmetry of swing phase (difference-major-minor value (DiffMJMn) 2 (0-8) - 1 (0-6) %), stance phase (DiffMJMn 2 (0-8) - 1 (0-6) %) or foot rotation (DiffMJMn 3 (0-10) - 3 (0-15)&#176;) (Figure 2B,C,D).
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/59103/59103fig1.jpg" /> 
Figure 1: Rasterstereographic results. Boxplots displaying measurement changes for (A) trunk length at the 3-months follow-up in comparison to the preoperative measurements (459 (33) - 448 (40)mm; p = 0.313; Tukey test), (B) Lordotic angle at the &#64257;rst postoperative measurement when compared to the preoperative values (thoracic spine vertebra 12 - dimple medium, from 28&#176; to 11&#176;; p &#60; 0.001; Tukey test), and (C-D) trunk inclination and lateral lilt over the course of one year (no significant difference). This figure has been adapted from reference26. <a href="https://www.jove.com/files/ftp_upload/59103/59103fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/59103/59103fig2.jpg" /> 
Figure 2: Gait and stance results. (A) Boxplots displaying a reduction in cadence from preoperatively over the postoperative course of 3 months (preoperatively to 7 days postoperatively: 98 (57-132) - 94 (43-119) steps/minute, p = 0.004; 3 months postoperatively: 91 (54-117) steps/minute, p = 0.006, Wilcoxon-test) and the preoperative, 7-days and 3-months postoperative treadmill results for (B) swing phase, (C) stance-phase and (D) foot-rotation grouped according to subjective pain relief after surgery in percentage (&#60;30%, 30-74%, &#62;75%). From preoperatively to 3-months postoperatively we detected significant changes for most spatiotemporal parameters (swing phase p = 0.01; stance phase p &#60; 0.001; foot rotation p = 0.001). No significant improvements were however observed with respect to their effect on gait symmetry (swing phase (difference-major-minor value (DiffMJMn) 2 (0-8) - 1 (0-6)%) stance phase (DiffMJMn 2 (0-8) - 1 (0-6)%, ), or foot rotation (DiffMJMn 3(0-10) - 3(0-15)&#176;)). This figure has been adapted from reference26. <a href="https://www.jove.com/files/ftp_upload/59103/59103fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Watch this Scientific Journal Video about Evaluation of Patients' Posture and Gait Profile After Lumbar Fusion Surgery by Video Rasterstereography and Treadmill Gait Analysis at JoVE.com

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

Here, we present a protocol to analyze the posture and the gait of patients after lumbar fusion surgery by means of high-resolution video rasterstereography and a treadmill equipped with an integrated sensor mat. Allowing critical functional postoperative evaluation on a less subjective level may enhance accuracy and reliability of indication for surgery.

This protocol provides guidance on how to perform high resolution video rasterstereography and treadmill gait analysis on patients after lumbar fusion ...

evaluation-patients-posture-gait-profile-after-lumbar-fusion-surgery

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17.5K Views.  University Hospital Bonn. Here, we present a protocol to analyze the posture and the gait of patients after lumbar fusion surgery by means of high-resolution video rasterstereography and a treadmill equipped with an integrated sensor mat. Allowing critical functional postoperative evaluation on a less subjective level may enhance accuracy and reliability of indication for surgery.

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

Manual Muscle Testing:  A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients

Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, and persistent nerve and muscle impairments after hospital discharge.1-6 Using an explicit protocol with a structured approach to training and quality assurance of research staff, manual muscle testing (MMT) is a highly reliable method for assessing strength, using a standardized clinical examination, for patients following ARDS, and can be completed with mechanically ventilated patients who can tolerate sitting upright in bed and are able to follow two-step commands. 7, 8 
This video demonstrates a protocol for MMT, which has been taught to &ge;43 research staff who have performed &gt;800 assessments on &gt;280 ARDS survivors. Modifications for the bedridden patient are included. Each muscle is tested with specific techniques for positioning, stabilization, resistance, and palpation for each score of the 6-point ordinal Medical Research Council scale.7,9-11 Three upper and three lower extremity muscles are graded in this protocol: shoulder abduction, elbow flexion, wrist extension, hip flexion, knee extension, and ankle dorsiflexion. These muscles were chosen based on the standard approach for evaluating patients for ICU-acquired weakness used in prior publications. 1,2.

Survivors of acute respiratory distress syndrome (ARDS) and critical illness frequently develop long-lasting muscle weakness. Manual muscle testing (MMT) is a standardized clinical examination commonly used to measure strength of peripheral skeletal muscle groups. This video demonstrates MMT using the 6-point Medical Research Council scale.

Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, ...

Clinical Assessment of Spatiotemporal Gait Parameters in Patients and Older Adults

Spatial and temporal characteristics of human walking are frequently evaluated to identify possible gait impairments, mainly in orthopedic and neurological patients1-4, but also in healthy older adults5,6. The quantitative gait analysis described in this protocol is performed with a recently-introduced photoelectric system (see&#160;Materials table) which has the potential to be used in the clinic because it is portable, easy to set up (no subject preparation is required before a test), and does not require maintenance and sensor calibration. The photoelectric system consists of series of high-density floor-based photoelectric cells with light-emitting and light-receiving diodes that are placed parallel to each other to create a corridor, and are oriented perpendicular to the line of progression7. The system simply detects interruptions in light signal, for instance due to the presence of feet within the recording area. Temporal gait parameters and 1D spatial coordinates of consecutive steps are subsequently calculated to provide common gait parameters such as step length, single limb support and walking velocity8, whose validity against a criterion instrument has recently been demonstrated7,9. The measurement procedures are very straightforward; a single patient can be tested in less than 5 min&#160;and a comprehensive report can be generated in less than 1&#160;min.

This protocol is used to evaluate spatial and temporal gait variables of neurological/orthopedic patients and older persons by means of a recently-introduced floor-based photocell system.

Spatial and temporal characteristics of human walking are frequently evaluated to identify possible gait impairments, mainly in orthopedic and ...

Isolation of Endothelial Progenitor Cells from Healthy Volunteers and Their Migratory Potential Influenced by Serum Samples After Cardiac Surgery

Endothelial progenitor cells (EPCs) are recruited from the bone marrow under pathological conditions like hypoxia and are crucially involved in the neovascularization of ischemic tissues. The origin, classification and characterization of EPCs are complex; notwithstanding, two prominent sub-types of EPCs have been established: so-called &#34;early&#34; EPCs (subsequently referred to as early-EPCs) and late-outgrowth EPCs (late-EPCs). They can be classified by biological properties as well as by their appearance during in vitro culture. While &#34;early&#34; EPCs appear in less than a week after culture of peripheral blood-derived mononuclear cells in EC-specific media, late-outgrowth EPCs can be found after 2-3 weeks. Late-outgrowth EPCs have been recognized to be directly involved in neovascularization, mainly through their ability to differentiate into mature endothelial cells, whereas &#34;early&#34; EPCs express various angiogenic factors as endogenous cargo to promote angiogenesis in a paracrine manner. During myocardial ischemia/reperfusion (I/R), various factors control the homing of EPCs to regions of blood vessel formation.
Macrophage migration inhibitory factor (MIF) is a chemokine-like pro-inflammatory and ubiquitously expressed cytokine and was recently described to function as key regulator of EPCs migration at physiological concentrations1. Interestingly, MIF is stored in intracellular pools and can rapidly be released into the blood stream after several stimuli (e.g. myocardial infarction). 
This protocol describes a method for the reliable isolation and culture of early-EPCs from adult human peripheral blood based on CD34-positive selection with subsequent culture in medium containing endothelial growth factors on fibronectin-coated plates for use in in vitro migration assays against serum samples of cardiac surgical patients. Furthermore, the migratory influence of MIF on chemotaxis of EPCs compared to other well-known angiogenesis-stimulating cytokines is demonstrated.

Endothelial progenitor cells (EPCs) are crucially involved in the neovascularization of ischemic tissues. This method describes the isolation of human EPCs from peripheral blood, as well as the identification of their migratory potential against serum samples of cardiac surgical patients.

Endothelial progenitor cells (EPCs) are recruited from the bone marrow under pathological conditions like hypoxia and are crucially involved in the ...

An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model

Pedicle screw fixation is the gold standard for the treatment of spinal diseases. However, many studies have reported the issue of loosening pedicle screws after spinal surgery, which is a serious concern. To address this problem, diverse types of pedicle screws have been examined to identify those with good fixation strength and osseointegration in spine bone. The porcine spine is a good alternative for the human spine in the evaluation of pedicle screws due to the anatomical size, mechanical characteristics, and cost. Although several studies have reported that pedicle screws are efficient in the porcine model, no study has described detailed protocols for the evaluation of a pedicle screw using the porcine model. Here, we describe a detailed method for evaluating transpedicular screws using an in vivo porcine lumbar spine model. The technical details for anesthesia, spine surgery, and harvest provided here will facilitate with the evaluation of the transpedicular screw fixation model.

An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model

Here, we introduce a method to evaluate transpedicular screws by using an in vivo porcine lumbar spine model.

Pedicle screw fixation is the gold standard for the treatment of spinal diseases. However, many studies have reported the issue of loosening pedicle ...

Mechanical and Controlled PRP Injections in Patients Affected by Androgenetic Alopecia

23 patients (18 male and 5 female) aged 21-70 years who displayed male pattern hair loss (MPHL) in Stage 1 to Stage 5 as determined by the Norwood-Hamilton classification scale, and female pattern hair loss (FPHL) in Stage 1 to Stage 2 as determined by the Ludwig classification scale, were treated with non-activated autologous platelet-rich plasma (A-PRP). Autologous blood (55 mL) was harvested using sodium citrate as an anticoagulant. A-PRP (23 mL) was produced for all cases using a closed system according to the transfusion service protocol. Following centrifugation (260 x g for 10 min) the A-PRP was inserted in a laser light selector device, and after the centrifugation, 9 mL of A-PRP was collected.
The scalp of the patients affected by androgenetic alopecia (AGA) was divided into four areas (frontal, parietal, vertex, and occipital); local anesthesia was not performed. Interfollicular A-PRP injections (0.2 mL x cm2) were performed by controlled and mechanical injections scheduled at a depth of 5 mm using a medical injector gun. Treatment sessions were performed with a 30-day interval. For each patient, three treatment sessions were performed.
PRP was injected in the androgen-related areas of scalp affected by hair loss. Placebo (normal saline solution) was loaded in another syringe (10 mL) and injected on the adjacent side in a similar fashion.

This paper aims to describe the interfollicular autologous platelet-rich plasma injections (0.20 mL x cm2) in the scalp of 23 patients affected by androgenetic alopecia at a depth of 5 mm using a medical injector gun equipped with a 30 gauge needle, in three sessions.

23 patients (18 male and 5 female) aged 21-70 years who displayed male pattern hair loss (MPHL) in Stage 1 to Stage 5 as determined by the ...

Laparoscopic Radical Left Pancreatectomy for Pancreatic Cancer: Surgical Strategy and Technique Video

Radical resection margins, resection of Gerota&#8217;s (perirenal) fascia, and adequate lymph node dissection are crucial for an adequate oncological resection of left-sided pancreatic cancer. Several surgical techniques have been described in recent years, but few were specifically designed for minimally invasive approaches. This study describes and demonstrates a standardized and reproducible technique for an adequate oncological resection of pancreatic cancer: laparoscopic radical left pancreatectomy (LRLP).
A 61-year-old woman presented with an incidental finding of a 3 cm mass in the left pancreas suspect for malignancy. Imaging did not reveal distant metastases, central vascular involvement, or morbid obesity, hence the patient was suitable for LRLP. This study describes the main steps of LRLP for pancreatic cancer. First, the lesser sac is opened by transecting the gastrocolic ligament. The splenic flexure of the colon is mobilized and the inferior border of the pancreas including Gerota&#39;s fascia is dissected down to the inferior border of the spleen. The pancreas is tunneled and hung, including Gerota&#8217;s fascia with a vessel loop. At the pancreatic neck, a tunnel is created between the pancreas and the portal vein, likewise a vessel loop is passed. The pancreas is then transected using the graded compression technique with an endostapler. Both the splenic vein and artery are transected before completing the resection. The entire specimen is extracted in a retrieval bag via a small Pfannenstiel incision.
Duration of the surgery was 210 min with 250 mL blood loss. Pathology revealed a R0-resection (&#62;1 mm) of a well-to-moderately differentiated adenocarcinoma originating from an intraductal papillary mucinous neoplasm. A total of 15 tumor-negative lymph nodes were resected. This is a detailed description of LRLP for left-sided pancreatic cancer as is currently being used within the international, multicenter randomized DIPLOMA (Distal Pancreatectomy Minimally Invasive or Open for PDAC) trial.

Oncologically safe left pancreatectomy requires radical resection (R0), Gerota&#8217;s (perirenal) fascia resection, and adequate lymph node dissection. This study describes the technical details of laparoscopic radical left pancreatectomy (LRLP), used in the first international multicenter randomized trial comparing minimally invasive with open left pancreatectomy for pancreatic cancer, the DIPLOMA trial.

Radical resection margins, resection of Gerota&#8217;s (perirenal) fascia, and adequate lymph node dissection are crucial for an adequate oncological ...

OP-IVM: Combining In vitro Maturation after Oocyte Retrieval with Gynecological Surgery

The use of in vitro maturation (IVM) before gynecological operation (OP-IVM) is an extension of conventional IVM that combines IVM following oocyte retrieval with routine gynecological surgery. OP-IVM is suitable for patients undergoing benign gynecological surgery who have the need for fertility preservation (FP) or infertility treatments such as in vitro fertilization and embryo transfer (IVF-ET). In the operating room, patients undergoing benign gynecological surgery are first anesthetized and receive ultrasound-guided immature follicle aspiration (IMFA) treatment. As the subsequent gynecological surgery is performed, the cumulus-oocyte complexes (COCs) are examined, and the immature COCs are transferred into the IVM medium and cultured for 28-32 hours in the IVF laboratory. After assessment, mature oocytes in the MII stage will be selected and cryopreserved in liquid nitrogen for FP or fertilized by intracytoplasmic sperm injection (ICSI) for IVF-ET. By combining IVM with gynecological surgery, immature oocytes that would have been discarded can be saved and used for assisted reproductive technology (ART). The procedure, significance and critical aspects of OP-IVM are described in this article.

In vitro maturation (IVM) before gynecological operation (OP-IVM) combines IVM following oocyte retrieval with routine gynecological surgery and serves as an extension of conventional IVM applications for fertility preservation.

The use of in vitro maturation (IVM) before gynecological operation (OP-IVM) is an extension of conventional IVM that combines IVM following oocyte ...

Digital Home-Monitoring of Patients after Kidney Transplantation: The MACCS Platform

The MACCS (Medical Assistant for Chronic Care Service) platform enables secure sharing of key medical information between patients after kidney transplantation and physicians. Patients provide information such as vital signs, well-being, and medication intake via smartphone apps. The information is transferred directly into a database and electronic health record at the kidney transplant center, which is used for routine patient care and research. Physicians can send an updated medication plan and laboratory data directly to the patient app via this secure platform. Other features of the app are medical messages and video consultations. Consequently, the patient is better-informed, and self-management is facilitated. In addition, the transplant center and the patient's local nephrologist automatically exchange notes, medical reports, laboratory values, and medication data via the platform. A telemedicine team reviews all incoming data on a dashboard and takes action, if necessary. Tools to identify patients at risk for complications are under development. The platform exchanges data via a standardized secure interface (Health Level 7 (HL7), Fast Healthcare Interoperability Resources (FHIR)). The standardized data exchange based on HL7 FHIR guarantees interoperability with other eHealth solutions and allows rapid scalability to other chronic diseases. The underlying data protection concept is in concordance with the latest European General Data Protection Regulation. Enrollment started in February 2020, and 131 kidney transplant recipients are actively participating as of July 2020. Two large German health insurance companies are currently funding the telemedicine services of the project. The deployment for other chronic kidney diseases and solid organ transplant recipients is planned. In conclusion, the platform is designed to enable home monitoring and automatic data exchange, empower patients, reduce hospitalizations, and improve adherence, and outcomes after kidney transplantation.

The MACCS platform&#160;is a comprehensive telemedicine concept aiming at better outcomes after kidney transplantation by sharing key medical information between patients and physicians. A telemedicine team reviews incoming data to detect potential complications and to improve adherence in kidney transplant recipients to achieve better long-term outcomes.

The MACCS (Medical Assistant for Chronic Care Service) platform enables secure sharing of key medical information between patients after kidney ...

Evaluation of Fluid Overload by Bioelectrical Impedance Vectorial Analysis

Early detection and management of fluid overload are critically important in acute illness, as the impact of therapeutic intervention can result in decreased or increased mortality rates. Accurate fluid status assessment entails appropriate therapy. Unfortunately, as the gold standard method of radioisotopic fluid measurement is costly, time-consuming, and lacks sensitivity in the acute care clinical setting, other less-accurate methods are typically used, such as clinical examination or 24 h output. Bioelectrical impedance vectorial analysis (BIVA) is an alternative impedance-based approach, where the raw parameter resistance and reactance of a subject are plotted to produce a vector, the position of which can be evaluated relative to tolerance intervals in an R-Xc graph. The fluid status is then interpreted as normal or abnormal, based on the distance from the mean vector derived from a healthy reference population. The objective of the present study is to demonstrate how to evaluate the presence of fluid overload through bioelectrical impedance vectorial analysis and the impedance ratio measured with tetrapolar multi-frequency equipment in patients admitted to the emergency department.

In this study, we demonstrate how to evaluate the presence of fluid overload through bioelectrical impedance vectorial analysis (BIVA) and the impedance ratio measured using tetrapolar multi-frequency equipment in patients admitted to the emergency department. BIVA and impedance ratio are reliable and useful tools to predict poor outcomes.

Early detection and management of fluid overload are critically important in acute illness, as the impact of therapeutic intervention can result in ...

Clinical Application of Microscope-Assisted Minimally Invasive Anterior Lumbar Interbody Fusion

This study aims to investigate the technical aspects of microscope-assisted anterior decompression fusion and to introduce a spreader system suitable for minimally invasive anterior lumbar interbody fusion (Mini-ALIF). This article is a technical description of anterior lumbar spine surgery under a microscope. We retrospectively collected information on patients who underwent microscope-assisted Mini-ALIF surgery at our hospital between July 2020 and August 2022. A repeated-measures ANOVA was used to compare imaging indicators between periods. Forty-two patients were included in the study. The mean volume of intraoperative bleeding was 180 mL, and the mean operative time was 143 min. The mean follow-up time was 18 months. Apart from one case of peritoneal rupture, no other serious complications occurred. The postoperative foramen and disc height were both higher on average than before surgery. The spreader-assisted micro-Mini-ALIF is simple and easy to use. It can provide good intraoperative disc exposure, good discrimination of important structures, adequate spreading of the intervertebral space, and the restoration of the necessary intervertebral height, which is very helpful for less experienced surgeons.

The technique described in this article is well-suited to the Mini-ALIF procedure, allows for excellent exposure and decompression, and facilitates microscope-assisted manipulation.

This study aims to investigate the technical aspects of microscope-assisted anterior decompression fusion and to introduce a spreader system suitable for ...