Late-onset neutropenia after anti-CD20 therapy for multiple sclerosis, neuromyelitis optica spectrum disorders and MOG antibody-associated disease: A prospective study.

Late-onset neutropenia (LON) after anti-CD20 therapy is a poorly described side effect in inflammatory disorders of the CNS. In this prospective study, patients treated with Rituximab or Ocrelizumab for MS, neuromyelitis optica spectrum disorders or MOG antibody-associated disease (MOGAD) were asked to perform complete blood count (CBC) every two weeks for six months, with the aim of identifying LON. Out of 152 patients, two (1,32%) had an absolute neutrophil count <1,000/mm3: one patient with MOGAD had agranulocytosis and one patient with MS had grade 3 neutropenia. Both were asymptomatic. These results confirm that LON after anti-CD20 therapy in inflammatory disorders of the CNS is not exceptional. Nevertheless, this biological complication remains too infrequent to justify close systematic CBC follow-up.

Serotonin Selective Reuptake Inhibitors (SSRIs) and Stroke.

PURPOSE OF REVIEW: The interest in SSRIs after stroke has increased in the past few years, with better knowledge of post-stroke depression and with the demonstrated capacity of some SSRIs to act on the functional recovery of non-depressed subjects. RECENT FINDINGS: Arguments for the action of SSRIs in favour of post-stroke neurological function recovery have improved through new elements: basic science and preclinical data, positive clinical trials and repeated series of stroke patient meta-analysis, and confirmation of favourable safety conditions in post-stroke patients. Global coherence is appearing, showing that SSRIs improve stroke recovery in non-depressed patients when given for 3 months after the stroke, with highly favourable safety conditions and a favourable benefit/risk ratio. Large series are still needed.

Maverick total disc arthroplasty performs well at 10 years follow-up: a prospective study with HRQL and balance analysis.

PURPOSE: The treatment of low back pain associated to Disc Degenerative Disease (DDD) is still controversial. Segmental Fusion is the gold standard, but many studies have reported that motion-preserving devices bring substantial clinical benefits to patients. Concerns on the associated complications and on the long-term clinical effectiveness of such instrumentations are still present and have led recently to a decrease of the number of Lumbar Total Disk Replacements (TDR). The objective of this prospective study is to present the clinical and radiographic outcomes of the Maverick Lumbar disk prostheses (Medtronic, TE, Memphis, USA) at long-term follow-up. METHODS: Prospective, single center study of clinical outcome of the treatment with Maverick lumbar Prosthesis of patients with low back pain from DDD resistant to conservative treatment. Patients were examined preoperatively and at 3 months, 2 and 10 years post-operatively. Patients were examined preoperatively and at 3 months, 2 and 10 years post-operatively. Visual analog scale (VAS), Oswestry disability index (ODI) and 36-Item Short Form Health Survey questionnaire were assessed to study clinical outcomes. Radiographic studies allowed measurements of range of motion, adjacent segment disease and pelvic and lumbar parameters. RESULTS: From an initial cohort of 87 patients who underwent TDR between 2003 and 2007 with the Maverick prosthesis, 61 were available at Final follow-up (70%). The clinical outcomes measured by VAS and ODI showed a significant improvement in all the postoperative stages of the follow-up (FU). At 10 years-FU, ODI experienced a mean decrease of 21.1 points, VAS for back pain decreased up to 3.85 and substantial clinical benefit was reached for 55.6% of the patients. Although Mobility of the prosthesis was preserved in 76.8% of the cases, TDR was not clearly protective against ALD. CONCLUSIONS: A significant, clinically relevant, and lasting reduction of back pain has been achieved in patients who underwent a total disk arthroplasty or a Hybrid construct with Maverik prosthesis. TDR is a safe and effective technique to decrease pain in patients with one or two levels of DDD.

Analysis of cervical sagittal alignment variations after lumbar pedicle subtraction osteotomy for severe imbalance: study of 59 cases.

OBJECTIVE: To evaluate postoperative changes within the cervical alignment following surgical lumbar correction by pedicle subtraction osteotomy (PSO) in patients affected with sagittal global malalignment disease. METHODS: This was a monocentric, radiographic, and prospective study. 79 patients, who underwent sagittal correction by PSO, performed an EOS imaging pre- and postoperatively between January 2008 and December 2013 at the University Hospital of Bordeaux. Inclusion criteria were a performed pre- and postoperative EOS imaging and a preoperative C7SVA > 5 cm. Were excluded patients who did not allow EOS with a viewable cervical spine due to hyperkyphosis. The study involved the analysis of pelvic, lumbar, thoracic, cervical, and cranial parameters before and after the surgery. RESULTS: 59 patients met the criteria. Mean follow-up was 38 months. The lumbar PSO significantly improved sagittal alignment including L1S1 lordosis, T1T12 kyphosis, and C7SVA (p < 0.001). We did not reported a significant change within cervical parameters after PSO (C2C7 lordosis 22.7°-21.5° p = 0.64, C1C7 lordosis 50.6°-48.8° p = 0.56, C1C2 angle 28.2°-27.9° p = 0.82, C7 slope stayed constant 32.3°-30.5° p = 0.47, OC2 angle 15.54°-15.56° p = 0.99). However, cranial slope decreased significantly (p < 0.05). We did not find correlation between lumbar lordosis and cervical lordosis variations (R = 0.265). Cervical lordosis was highly correlated with the C7 slope (R = 0.597) and with the Spino Cranial Angle (R = - 0.867). CONCLUSION: Reciprocal changes in cervical spine after PSO are difficult to approach. Maintaining a horizontal gaze involves locoregional mechanisms of compensation adapting to the slope of C7. The cranial system by decreasing the cranial slope allows the gaze alignment and is the first compensation mechanism to get involved after a loss of lumbar lordosis. Restoring optimal C7SVA is necessary to prevent the development of secondary cervical painful symptomatology when the cranial compensation is outdated.

Meta-analysis of the effects of genetic polymorphisms on intervertebral disc degeneration.

INTRODUCTION: Chronic low back pain is a significant public health issue. Both its direct and indirect cost represents tens of billions of US dollars. Although chronic low back pain can be the result of many factors, the predominant cause is disc degeneration. Recent studies have shown genetic involvement in up to 74% of cases. This study aimed to evaluate genetic risk factors of disc degeneration by performing a systematic analysis of association studies. The objective is to provide a guide for practice by assessing the clinical relevance of current information. METHODS AND MATERIALS: We performed a meta-analysis of 3122 items collected from 6 databases. 74 articles were selected according to our inclusion criteria. 18 (24%) could be grouped into 16 meta-analyses of 16 mutations in 12 genes. The statistics of the meta-analysis were conducted through Revman 5.1 software. RESULTS: The items included are 10,250 cases and 14,136 controls. The GOLD range from 3.42 to 0.38. Two alleles were significantly associated with disc degeneration: IL-6 rs1800797 and MMP-9 rs17576 and one proved to be protective: IL-6 rs1800795. 13 meta-analyses did not yield significant results and methodological heterogeneity. DISCUSSION: The results highlight the lack of methodological rigor in most of the studies. The absence of international clinical and radiological classification of early disc degeneration, limits the homogeneity of studies. Understanding which populations are predisposed to this significant public health problem may change our approach to diagnostic and therapeutic methods. This work opens up enormous opportunities to provide a genetic solution and consider new diagnostic and therapeutic means to this public health problem.

Clinical and radiological outcomes of lumbar posterior subtraction osteotomies are correlated to pelvic incidence and FBI index : Prospective series of 63 cases.

PURPOSE: Pedicle subtraction osteotomy (PSO) is one of the surgical options for treating alignment disorders of the fused spine (due to post-surgical fusion or related to arthritis). It enables satisfactory sagittal realignment and improved function due to economic sagittal balance. The aim of this study was to analyze clinical and radiological results of PSO after a minimum follow-up of 2 years and demonstrate the benefit of sub-group analysis as a function of pelvic incidence (PI). METHODS: A descriptive prospective single center study of 63 patients presenting with spinal global malalignment who underwent correction by PSO. Function was assessed by the Oswestry disability index (ODI), a visual analog scale of lumbar pain (VAS) and a SF-36 questionnaire. Radiographic analyses of pre- and post-operative pelvic-spinal parameters were performed on X-rays obtained by EOS(®) imaging after 3D modeling. Global analysis and analysis of sub-groups as a function of pelvic incidence were performed and the full balance integrated index (FBI) was calculated. RESULTS: this series showed a marked clinical improvement and significant progress of functional scores. Global post-operative radiological analysis showed a significant improvement in all pelvic and spinal parameters. The mean correction obtained after PSO was 31.7° ± 8.4°, hence global improvement of lumbar lordosis of 22°. The sagittal vertical angle (SVA) decreased from +9 cm before surgery to +4.3 cm after surgery. Sub-group analysis demonstrated greater improvement in pelvic tilt, sacral slope and spinal parameters of patients with a small or moderate pelvic incidence; all had an FBI index <10°. Most of the pelvic and spinal parameters of patients with a large pelvic incidence were insufficiently corrected and they had an FBI index >10° CONCLUSION: PSO is a surgical procedure enabling correction of multiplane rigid spinal deformities that require major sagittal correction. It was seen to be highly effective in patients with a small or moderate pelvic incidence (PI <60°) but was sometimes less effective in patients with large pelvic incidence due to insufficient lordosis correction. Clinical results were highly correlated with the value of the FBI index.

Insufficient restoration of lumbar lordosis and FBI index following pedicle subtraction osteotomy is an indicator of likely mechanical complication.

PURPOSE: Pedicle subtraction osteotomies (PSO) enable correction of spinal deformities but remain difficult and are associated with high complication rates. This study aimed to prospectively review different post-operative complications and mechanical problems in patients who underwent PSO as treatment for sagittal imbalance as sequelae of degenerative disc disease or previous spinal fusion. METHOD: This was a descriptive prospective single center study of 63 patients who underwent sagittal imbalance correction by PSO. Radiographic analysis of pre- and post-operative pelvic and spinal parameters was completed based on EOS images following 3D modeling. Global and sub-group analyses were completed based on the Roussouly classification. A systematic analysis of post-operative complications was conducted during hospital stay and at follow-up visits. RESULTS: Complications included 15 cases (20.2%) of bilateral leg pain, with transient neurological deficit in 6 cases (9.5%), and 9 cases (12.5%) of early surgical site infections. Intra-operative complications included five tears of the dura mater and two cases of excessive blood loss (>5,000 mL). Two mortalities occurred from major intracerebral bleeds in the early post-operative period. Mechanical complications were principally non-union (9 cases) and junctional kyphosis (3 cases). All 19 post-operative complications (28.1%) were revised at an average of 2 years following surgery. All mechanical complications were found in the patients who had insufficient imbalance correction and this was mainly associated with high PI (>60°) or a moderate PI (45-60º) combined with excess FBI pre-operatively that remained >10° post-operatively. CONCLUSION: Infection and neurologic complications following PSO are relatively common, and frequently reported in the literature. The principal cause of mechanical complications, such as non-union or junctional kyphosis, was insufficient sagittal correction, characterized by post-operative FBI >10°. The risks of insufficient correction are greater in patients with higher pelvic incidence and those patients who required very high correction.

Sagittal balance parameters influence indications for lumbar disc arthroplasty or ALIF.

UNLABELLED: Chronic lower back pain is a potentially incapacitating condition associated with disc degeneration. Although therapy is primarily pharmaceutical, surgery comprising arthrodesis constitutes an alternative. Anterior intersomatic lumbar arthrodesis (ALIF, anterior interbody lumbar fusion) is the reference approach, although total disc arthroplasty may also be undertaken. Analysis of pelvic and spinal parameters provides the best indication of sagittal balance. MATERIALS AND METHODS: This was a prospective study in a continuous series of 99 patients presenting chronic lower back pain due to disc disease. Pelvic incidence, sacral slope, pelvic tilt, spino-sacral angle (SSA) and the four back types in the Roussouly classification were studied in radiographs of the whole spine under load using an EOS imaging system. RESULTS: The pre-operative SSA value for the study population was 126.09° ± 8.45° and the mean spine tilt angle was 90° compared with 95° in healthy subjects. Following surgery, the SSA was considerably increased in the discal arthroplasty, resulting in a significantly more balanced spinal position. In the group of patients undergoing arthrodesis using the ALIF technique, no such significant improvement was found despite the use of a lordosis cage. We showed that in cases of low pelvic incidence, it was necessary to maintain a Roussouly type 1 or 2 back without increasing lordosis. The results demonstrated the value of L4-L5 disc prostheses in these subjects. L5-S1 arthrodesis seemed a more suitable approach for treating patients with elevated sacral slope (back type 3 or 4). This new type of analysis of sagittal parameters should be performed prior to all surgical procedures involving lumbar prostheses.

Equilibrium of the human body and the gravity line: the basics.

INTRODUCTION: Bipedalism is a distinguishing feature of the human race and is characterised by a narrow base of support and an ergonomically optimal position thanks to the appearance of lumbar and cervical curves. MATERIALS: The pelvis, adapted to bipedalism, may be considered as the pelvic vertebra connecting the spine to the lower limbs. Laterally, the body's line of gravity is situated very slightly behind the femoral heads laterally, and frontally it runs through the middle of the sacrum at a point equidistant from the two femoral heads. RESULTS: Any abnormal change through kyphosis regarding the spinal curves results in compensation, first in the pelvis through rotation and then in the lower limbs via knee flexion. This mechanism maintains the line of gravity within the base of support but is not ergonomic. To analyse sagittal balance, we must thus define the parameters concerned and the relationships between them. CONCLUSION: These parameters are as follows: for the pelvis: incidence angle, pelvis tilt, sacral slope; for the spine: point of inflexion, apex of lumbar lordosis, lumbar lordosis, spinal tilt at C7; for overall analysis: spino-sacral angle, which is an intrinsic parameter.

Sagittal imbalance cascade for simple degenerative spine and consequences: algorithm of decision for appropriate treatment.

INTRODUCTION: The main objective of all the sagittal compensating mechanisms is to allow a subject to stand and keep an erect position. MATERIALS AND METHODS: The cascade of compensating mechanisms appears progressively with the increasing amount of imbalance of the spine until compensation is no longer possible. The loss of lumbar lordosis can be considered as the initiating event of sagittal imbalance. This loss of the normal lordosis pushes the C7 plumb line forward. RESULTS: The assessment of sagittal balance has to include to be complete: a parameter measuring the global balance of the trunk, either C7 plumb line and sacral plateau, the position of the pelvis rotation by the pelvic tilt, and a description of the position of the lower limbs. Those three parameters have been taken into account by the newly described method called full balance integrated (FBI). This evaluation is easily done on a sagittal full spine standing X-ray from C2 to the pelvis, including the first 10 cm of the femur. CONCLUSION: Three questions to answer: What is the value of the pelvis incidence? Is the patient balanced? Are there compensatory mechanisms?

Late-onset neutropenia after RITUXIMAB therapy for multiple sclerosis, neuromyelitis optica spectrum disorders and MOG-antibody-associated diseases.

Few cases of late onset neutropenia after RITUXIMAB treatment (LONART) have been reported in patients with neuroinflammatory disorders. We conducted a retrospective analysis of patients treated with RITUXIMAB for neuromyelitis optica spectrum disorders (NMOSD), MOG-antibody-associated disease (MOGAD) and multiple sclerosis (MS) at the Toulouse University Hospital from November 2007 to October 2019. Ten patients with LONART were identified in a total of 385 patients: 4/25 were MOGAD patients, 2/20 were NMOSD patients and only 4/340 were MS patients (p < 0,05). Six required intravenous antibiotics whereas four were asymptomatic. Eight patients received new infusions of RITUXIMAB after resolution of their neutropenia. Neutropenia recurred in one patient.

Off-label use of tocilizumab in neuromyelitis optica spectrum disorders and MOG-antibody-associated diseases: A case-series.

BACKGROUND: The objective of the study was to evaluate the indication, efficacy and safety of tocilizumab, a humanized anti-interleukin-6 receptor antibody, in patients with neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody associated diseases (MOGAD) encountered in current neurological practice. MATERIAL AND METHODS: We conducted a retrospective analysis of an exhaustive cohort of patients with inflammatory CNS disorders at Toulouse University Hospital, France, from 2014 to 2020. Efficacy was evaluated with clinical outcome by the Annual Relapse Rate, and radiological outcome with MRI data. The other outcomes were adverse events and effectiveness according to the form of injection (intravenous or subcutaneous). RESULTS: Seven patients were treated with tocilizumab: four patients had NMOSD with AQP4+ antibodies (57%) and three had MOGAD (43%). Tocilizumab was administered in the presence of persistent clinical activity and/or severe side effects with other immunosuppressant medications. The median follow-up on tocilizumab was 23 months (4-50 months). All patients started with monthly intravenous injection, then three switched to a subcutaneous form. All patients were relapse-free throughout the duration of treatment with tocilizumab, and one presented with a new cervical lesion on MRI. Four patients had no adverse effect, two had a significant increase in infection rate, and one had dyslipidemia. CONCLUSION: tocilizumab appears to be an effective therapy for patients with refractory NMOSD or MOGAD. Subcutaneous and intravenous injections appear to be equally effective.

Cost of red blood cell transfusion; evaluation in a French academic hospital.

OBJECTIVES: The economic impact of Patient blood management (PBM) must be assessed beyond the acquisition cost of blood products alone. The estimate of indirect costs may vary depending on the organization and the elements taken into account. The transposition of data from the literature into a specific local context is therefore delicate. The objective of this work was to evaluate the overall cost of red blood cell concentrate (RBC) transfusion from a French healthcare establishment point of view. METHODS: We carried out an activity based costing analysis in our hospital for the year 2018. The steps of the transfusion process and additional costs were detailed and cumulated (resource consumption, labor time, frequency) to populate the ABC model. Several scenarios were developed focusing either on RBC, all blood products or the surgical activity, and a univariate sensitivity analysis was conducted. RESULTS: The average total cost of transfusion, including acquisition cost, was 339,64 euros per RBC transfused. The cost of administration was 138.41 euros/RBC. Focusing only on surgical activities increased this cost (152.43 euros) while taking all blood products into account reduced it (92.49 euros). CONCLUSION: The difference in our results with the literature confirms the local variability in the cost of transfusion, which may affect the economic impact of PBM. Our study related to the specific context of a single French institution has limitations that a multicenter study would clarify in order to carry out economic modelling of transfusion optimization and alternatives and to guide the choice of PBM strategies at the national level.

A simple experimental method to study depigmenting agents.

The first objective of the study was to verify that a controlled UV exposure of four areas of the forearms together with randomized product application enabled to compare treatment efficacy and then to compare the depigmenting efficacy of different products with a simple experimental method. Sixteen volunteers received 0.7 minimal erythermal dose for four consecutive days. Products tested were ellagic acid (0.5%), vitamin C (5%) and C8-LHA (2%). Product application started 72 h post last exposure, was repeated for 42 days, the control zone being exposed, non-treated. Colour measurements included Chromameter, Chromasphere, Spectro-colorimeter and visual assessment. Comparison of colour values at day 1 and at day 7 showed that all zones were comparably tanned, allowing a rigorous comparison of the treatments. We report a new simple experimental model, which enables the rapid comparison of different depigmenting products. The efficacy and good tolerance of C8-LHA make it an excellent candidate for the treatment of hyperpigmentory disorders.

[Body mass index and albuminemia in patients under mechanical circulatory assistance before cardiac transplantation]. / Indice de masse corporelle et albuminémie péri-implantatoires de patients sous assistance circulatoire mécanique (ACM) en attente d'une transplantation cardiaque.

OBJECTIVE: To evaluate the prognostic influence of peri-implantation nutritional status of patients under mechanical circulatory assist (MCA) prior to cardiac transplantation (CT). STUDY DESIGN: Retrospective analysis of patients with cardiogenic shock included from June 1997 to December 2002. PATIENTS AND METHODS: Evaluation at MCA's implantation, at day (D) 30 and at CT or patient's death (D) of body mass index (BMI=body weight (kg)/size (m(2)), albuminemia (Alb g/l), expressed as median values (med) and range (min-max). Odds ratio (OR) and CI 95%) were calculated. A multivariate analysis was performed to determine variables related to D or CT success. RESULTS: Thirty-four patients (30 men), median age 40.5 years (10-63), were included. MCA types were cardiac pumps (N=3); pneumatic (N=18) or electric (N=5) ventricular assist devices and artificial heart (N=8). Global mortality was 56% (19 over 34 patients) and at implantation in the global population (N=34) BMI was 19.4 (9.3-28.1) and Alb 24.6 g/l (15-37.5). At MCA's implantation and D30 respectively, 38 and 42% of the patients had a severe hypoAlb (Alb<30 g/l) and a BMI<19 attesting of a seriously deteriorated nutritional status. No significant statistical difference was observed on median BMI of transplanted patients T (N=15) and expired patients D (N=19). Alb was significantly different (p<10(-4)) between T and D patients: median Alb: 30 g/l (20-37.5) in T patients, 20 g/l (15-31) in D patients. HypoAlb<21 g/l was an independent prognostic factor of death (p=0.004; OR: 0.541; IC95% : 0.36-0.82) and Alb>33 g/l an independent prognostic factor of CT success (p=0.003; OR:1.38; IC95% : 1.12-1.71). CONCLUSION: These results seem to demonstrate that at MCA implantation, a seriously deteriorated albuminemia level (<30 g/l) negatively impacts patients overall survival after CT.

A new procedure for fractures of the medial epicondyle in children: Mitek(®) bone suture anchor.

We present a new bone suture anchor technique for fractures of the medial epicondyle. The hypothesis was that the results would be similar to those with the divergent K-wire fixation. This retrospective study included 40 patients who presented with displaced fractures of the medial epicondyle: one group was treated with a Mitek(®) non-resorbable bone suture anchor (group A: n=21), the other by K-wire fixation (group B: n=19). A medial approach was taken with an anchor placed above the olecranon fossa. The epicondyle was then repositioned by bone suture. After a mean follow-up of 18.6 months, union was obtained in all epicondyles. There was no difference in flexion-extension of the elbow. The rate of hypertrophy of the medial epicondyle was similar in both groups (57%). The bone suture anchor of the medial epicondyle is an effective technique that does not require hardware removal and is an alternative treatment option to divergent K-wire fixation.

Age-related mechanical properties of human skin: an in vivo study.

We have investigated in vivo how various viscoelastic parameters that describe the mechanical properties of the human skin may vary with age. Accordingly, we have used a mechanical device that records the torsional extensibility of the skin. When submitted to a low torque, the time-response curve of the skin affords the determination of the immediate extensibility (UE), the immediate recovery (UR), the viscoelastic part of the deformation (UV), the elastic recovery (UR/UE), and the creep relaxation time (tau). Because the skin thickness varies with age and primarily governs the mechanical properties, it was measured through an ultrasound technique at the same sites (forearm) where the torque was applied. The results show that the skin maintains its thickness and extensibility up to the seventh decade as opposed to its elasticity or recovery capacities, which decrease from an early age. The viscous part of the deformation is constant through life, whereas the creep relaxation time decreases linearily with age. Except for skin thickness, no differences in these parameters between men and women were detected. The significance of these results are discussed in terms of structure alterations. The determination of the elastic recovery (UR/UE) appears to be a parameter of choice for illustrating skin aging.

Assessment of aging of the human skin by in vivo ultrasonic imaging.

The ultrasonic imaging technique that we have developed provides cross-sectional images of human skin in vivo with a resolution of about 80 microns axially (i.e., deep into the skin) and 250 microns lateral (parallel to the surface). In order to study aging skin, we obtained ultrasonic images from the mid-forearm (volar and dorsal sides) of 142 women. Ultrasonically, on the images, the dermis appears composed of two bands: a dark superficial one where the ultrasonic waves are propagated in a relatively homogeneous or non-echogenic medium, and a deeper one, which is lighter in color, suggesting a heterogeneous medium. Our results show that skin is thicker on the dorsal than on the volar forearm. In contrast to previously published results, skin thickness remains constant until the seventh decade of life, diminishing thereafter. The relative thickness of the two bands show marked variations with age: a progressive thickening of the dark band, from zero in infants to approximately 75% of total skin thickness in aged subjects, while the light band shows the inverse trend. Comparing the amplitude of the bands on the volar and dorsal forearm, the relative thickness of the dark band is larger on the dorsal (exposed) side and increases with age. These findings and the analysis of variously stained biopsies taken in some of our patients lead us to assign this dark band to a zone in the upper dermis where the collagen network is delicate, dense, and well organized. This is supported by some data in the literature. The thickness of this subepidermal non-echo-genic band appears to be a far more sensitive marker of skin aging at the dermal level than is the measurement of skin thickness.

Mechanical properties and Young's modulus of human skin in vivo.

The mechanical properties of the in vivo dermis were measured by means of a torque applied to the skin. The resulting deformation of 2-6 degrees, including the immediate and delayed visco-elastic components, as well as the relaxation were measured, and the raw values corrected for a constant skin thickness. The experiment performed on 138 individuals from 3 to 89 years old revealed a diminished elasticity and stretchability after the age of 30, associated with an increase in the visco-elastic component. The Young's modulus doubles with age. The results are discussed in terms of the various models proposed to explain dermal structure.