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ABSTRACT: : Arthroscopic suture fixation of tibial eminence fractures using FiberWire is a favorable therapeutic option. The application of biodegradable material may be of advantage especially during childhood. The aim of this study was to evaluate the biomechanical properties using the biodegradable suture materials PDS II and Vicryl compared with FiberWire.
: Bone mineral density was evaluated by pqCT in 18 human knee specimens and 3 similar groups were formed. A standardized anterior tibial eminence fracture was created and suture fixation was performed using each suture material (PDS II, Vicryl, FiberWire) in 6 specimens. Cyclic testing and destructive loading to failure was conducted.
: Both testing modalities showed PDS II to be inferior to the other evaluated suture materials. Although significantly higher failure loads were seen with FiberWire sutures, Vicryl yielded comparable stiffness in load-to-failure testing. No significant differences between Vicryl and FiberWire could be observed under nondestructive cyclic conditions.
: Even though FiberWire yields a superior ultimate failure load, Vicryl presented comparable results under cyclic conditions.
: For tibial eminence fractures in children, Vicryl should be considered as an alternative biodegradable suture material. The use of PDS II cannot be advocated.
Journal of pediatric orthopedics 06/2013; 33(4):409-14. · 1.23 Impact Factor
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ABSTRACT: INTRODUCTION: Although the formation of neutrophil (PMN) extracellular traps (NETs) has been detected during infection and sepsis, their role in vivo is still unclear. This study was performed in order to evaluate the influence of NETs depletion by administration of recombinant human (rh)DNase on bacterial spreading, PMN tissue infiltration and inflammatory response in a mouse model of polymicrobial sepsis. METHODS: In a prospective controlled double-armed animal trial, polymicrobial sepsis was induced by cecal ligation and puncture (CLP). After CLP, mice were treated with rhDNase or phosphate buffered saline, respectively. Survival, colony forming unit (CFU) counts in the peritoneal cavity, lung, liver and blood were determined. PMN and platelet counts, IL-6 and circulating free (cf)-DNA/NETs levels were monitored. PMN infiltration, as well as organ damage, was analyzed histologically in the lungs and liver. Capability and capacity of PMN to form NETs were determined over time. RESULTS: cf-DNA/NETs were found to be significantly increased 6, 24, and 48 hours after CLP when compared to the levels determined in sham and naïve mice. Peak levels after 24 hours were correlated to enhanced capacity of bone marrow-derived PMN to form NETs after ex vivo stimulation with phorbol-12-myristate-13-acetate at the same time. rhDNase treatment of mice resulted in a significant reduction of cf-DNA/NETs levels 24 hours after CLP (P < 0.001). Although overall survival was not affected by rhDNase treatment, median survival after 24 hours was significantly lower when compared with the CLP group (P < 0.01). In mice receiving rhDNase treatment, CFU counts in the lung (P < 0.001) and peritoneal cavity (P < 0.05), as well as serum IL-6 levels (P < 0.001), were found to be already increased six hours after CLP. Additionally, enhanced PMN infiltration and tissue damage in the lungs and liver were found after 24 hours. In contrast, CFU counts in mice without rhDNase treatment increased later but more strongly 24 hours after CLP (P < 0.001). Similarly, serum IL-6 levels peaked after 24 hours (P < 0.01). CONCLUSIONS: This study shows, for the first time, that depletion of NETs by rhDNase administration impedes the early immune response and aggravates the pathology that follows polymicrobial sepsis in vivo.
Critical care (London, England) 07/2012; 16(4):R137. · 4.61 Impact Factor
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ABSTRACT: Despite the frequency of distal radius fractures, the optimal treatment remains without consensus opinion. A trend toward increased distal radius fracture open reduction and internal fixation has been identified, with biomechanical and clinical studies suggesting treatment advantages of certain fixation methods over others. Well-controlled patient trials are still missing to lend objective findings to management algorithms. This article reviews the literature over the past 5 years to guide our management regarding this common upper-extremity injury.
The Journal of hand surgery 07/2012; 37(8):1718-25. · 1.33 Impact Factor
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ABSTRACT: The aim of our study was to investigate trends over time in the mortality of elderly patients after femoral neck fractures treated with bipolar hemiarthroplasty.
Altogether 487 cases of femoral neck fracture treated with bipolar hemiarthroplasty were observed during a 20-year period. Mortality rates were calculated for five years postoperatively. To account for the age distribution of the study population standardised mortality ratios (SMR) with respect to the age-specific mortality of the German population were determined and compared. Additional changes of the SMRs over time and the influence of the time delay before surgery on long-term mortality were evaluated.
Femoral neck fractures treated with bipolar hemiendoprosthesis have a significant impact on mortality. Postoperative mortality is increased in patients of all age groups, but the effect diminishes in higher age groups. The influence on mortality was significantly greater for men than for women. The SMR has decreased from 3.52 before 1995 to 1.2 after 2006. Since 2006 there is no longer an increase in mortality after surgical treatment of a femoral neck fracture compared to general German population of the same age.
Femoral neck fractures treated with bipolar hemiendoprosthesis result in a significantly increased mortality, however in our population this impact has significantly decreased over time. The effect on mortality is less in women and higher age groups than in men and younger patients. No influence of the time between accident and surgery on mortality could be detected.
International Orthopaedics 06/2012; 36(10):2021-6. · 2.03 Impact Factor
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ABSTRACT: Operative treatment of patella fractures is frequently associated with implant failure and secondary dislocation which can be attributed to the employed hardware. Therefore, a 2.7 mm fixed-angle plate designed for the treatment of patella fractures was tested biomechanically against the currently preferred methods of fixation. It was hypothesized that under simulated cyclic loading fixed-angle plating would be superior to modified anterior tension wiring or cannulated lag screws with anterior tension wiring.
Eighteen human cadaver knees, matched by bone mineral density and age, were divided into three groups of six. After setting a transverse patella fracture each group received one of the osteosyntheses mentioned above. Repetitive testing over 100 cycles was performed at non-destructive loads by simulating knee motion from 90° flexion to full extension.
Anterior tension wiring as well as lag screws with tension wiring showed significant fracture displacement after the initial cycle already. Both constructs, lag screws plus wiring (3.7 ± 2.7 mm) as well as tension wiring alone (7.1 ± 2.2 mm) displayed fracture displacement of >2 mm which is clinically regarded as failure. Those patellae stabilized with fixed-angle plates showed no significant fracture gap widening after completion of 100 cycles (0.7 ± 0.5 mm). The differences between the fixed-angle plate group and the other two groups were statistically significant (p<0.05).
In contrast to modified anterior tension wiring and cannulated lag screws with anterior tension wiring the bilateral fixed-angle plate was the only fixation device to stabilize transverse patella fractures securely and sustainably.
Injury 05/2012; 43(8):1290-5. · 1.98 Impact Factor
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ABSTRACT: Scaphoid fractures in children are rare injuries. A complete scaphoid waist fracture in a 13-year-old boy after fall on the
extended wrist is reported. Following early diagnosis by MRI, the fracture healed uneventful with conservative treatment.
The appropriate diagnostic approach and the advantages of MRI for suspected scaphoid fractures in children are discussed.
European Journal of Trauma and Emergency Surgery 04/2012; 34(2):131-134. · 0.33 Impact Factor
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ABSTRACT: Background:In recent years, there has been a trend from operative to conservative management of complete acromioclavicular separations.
Despite this, surgical treatment is still recommended to manual workers and athletes, who account for a large part of the
patients. The objective of this study was to evaluate the functional outcome of type III separations according to Tossy managed
by temporary arthrodesis of the acromioclavicular joint combined with coracoclavicular augmentation. Special attention was
paid to sport exercising patients.
Patients and Methods:In this study, 32 patients (mean age 39 years) with a complete acromioclavicular separation were investigated. All of them
underwent a surgical treatment managed by temporary acromioclavicular arthrodesis with two parallel k-wires and augmentation
of the coracoclavicular ligaments with a biodegradable cord (PDS). Functional outcome was assessed after an average follow-up
of 36 months by using the Constant-Murley-, Neer- and DASH-score. Additionally, incidence of complications and subjective
results were observed.
Results:Evaluation of the data, obtained from the scores, revealed an excellent result for the Constant-Murley- and DASH-score for
84% of the patients. Regarding the Neer-score, 78% had an excellent outcome. Eighty-four percent of the patients assessed
revealed an excellent to fair subjective result. Cosmetic reasons were most frequently the cause for discontentedness. Minor
complications occurred in three patients without severe sequelae. All patients returned back to former working and sport activity
level.
Conclusion:Surgical treatment of complete acromioclavicular separations by temporary arthrodesis with two k-wires and coracoclavicualar
PDS-augmentation results in good to excellent function. It is associated with a low complication rate and a high patient contentedness.
Particularly for athletes in non-contact sports this surgical technique can still be recommended.
European Journal of Trauma and Emergency Surgery 04/2012; 34(1):43-48. · 0.33 Impact Factor
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ABSTRACT: The predictive value of circulating free DNA/neutrophil extracellular traps (cf-DNA/NETs) has recently been shown in patients
with major trauma for sepsis, multiple organ failure, and mortality. Here we report on the predictive potential of cf-DNA/NETs
for mortality in patients with severe burn injury. In a prospective study 32 patients with severe burn injury were included.
Blood samples were sequentially obtained on day1, 3, 5, and 7 after admission. cf-DNA/NETs was directly quantified from plasma
by means of rapid fluorescence assay. Time kinetics of cf-DNA/NETs were correlated with clinical data, C-reactive protein
(CRP), procalcitonin (PCT), and interleukin (IL)-6. Furthermore sensitivity, specificity, and positive and negative predictive
value, as well as receiver operation characteristic (ROC) curves were calculated. Seven patients died within the first month
after burn injury. cf-DNA/NETs values from these patients were significantly increased already on day1 and 3 after admission
compared with patients who survived (p<0.01). In contrast, PCT levels of nonsurvivors were significantly elevated on day3 and 5 (p<0.01), while CRP and IL-6 did not show any significant difference between survivors and nonsurvivors. At a cutoff of 255ng/ml,
cf-DNA/NETs had sensitivity of 0.8 and specificity of 0.74. ROC revealed largest areas under the curve (AUC) for cf-DNA/NETs
on day1 (0.851) and 3 (0.883) after admission. For all values between day1 and 7, AUC was 0.815. cf-DNA/NETs seems to be
a rapid, valuable marker for prediction of mortality in burn patients. A larger confirmation trial ought to be carried out.
KeywordsNeutrophil extracellular traps (NETs)-Neutrophils-Inflammation-Outcome-Circulating free DNA
European Journal of Trauma and Emergency Surgery 04/2012; 36(6):551-557. · 0.33 Impact Factor
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ABSTRACT: Dislocations of the elbow account for 20% of all dislocations. Thus, after the shoulder, the elbow joint is the joint most
frequently afflicted by dislocations. A distinction is made between simple elbowdislocations without associated fractures
and fracture-dislocations of the elbow, which are frequently referred to as complex elbow dislocations. Treatment principles
are reduction of the joint, stabilization of associated fractures, and early motion. Ligament repairs or reconstruction and
hinged external fixators are necessary in some cases to restore stability for early motion. In general, simple dislocations
have a better prognosis than complex dislocations.
European Journal of Trauma and Emergency Surgery 04/2012; 34(2):120-130. · 0.33 Impact Factor
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ABSTRACT: PURPOSE: A bilateral fixed-angle plate was biomechanically compared to the two currently preferred methods of osteosynthesis for transverse patella fractures. It was hypothesized that the new angle-stable implant would provide a secure and sustainable fracture fixation, superior to the established standard techniques. METHODS: Twenty-one identical patellae made of polyurethane foam (Sawbones(®)), osteotomized to create a transverse two-part fracture, were fixed with modified anterior tension wiring, cannulated lag screws with anterior tension wiring or bilateral polyaxial 2.7-mm fixed-angle plates. The testing protocol consisted of 10,000 repetitive cycles using a non-destructive physiological load between 100 and 300 N at a simulated knee flexion of 60°. RESULTS: All 21 Sawbone(®)-patellae sustained repetitive loading up to 10,000 cycles without failing. The anterior tension wire group displayed significant displacement of the fracture gap (0.7 ± 0.2 mm) during cyclic loading, while both lag screws with tension wiring and bilateral fixed-angle plates showed no fracture gap widening at all (p < 0.01). CONCLUSION: The bilateral fixed-angle plate and cannulated lag screws with anterior tension wiring preserved a constantly reduced fracture gap over 10,000 tensile cycles in contrast to modified anterior tension wiring, which exhibited significant widening of the gap after initial loading. Results of in vitro testing indicate that bilateral fixed-angle plates provide sustainable fixation stability offering a promising new option in the treatment for transverse patella fractures.
Knee Surgery Sports Traumatology Arthroscopy 04/2012; · 2.21 Impact Factor
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ABSTRACT: Neutrophil extracellular traps (NET) consist of a DNA scaffold that can be destroyed by Deoxyribonuclease (DNase). Thus DNases are potential prerequisites for natural counter regulation of NETs formation. In the present study, we determined the relationship of NETs and DNase after major trauma.
Thirty-nine major trauma patients, 14 with and 25 without sepsis development were enrolled in this prospective study. Levels of cell-free (cf)-DNA/NETs and DNase were quantified daily from admission until day 9 after admission.
Levels of cf-DNA/NETs in patients who developed sepsis were significantly increased after trauma. In the early septic phase, DNase values in septic patients were significantly increased compared to patients without sepsis (P < 0.05). cf-DNA/NETs values correlated to values of DNase in all trauma patients and patients with uneventful recovery (P < 0.01) but not in septic patients. Recombinant DNase efficiently degraded NETs released by stimulated neutrophils in a concentration-dependent manner in vitro.
DNase degrades NETs in a concentration-dependent manner and therefore could have a potential regulatory effect on NET formation in neutrophils. This may inhibit the antibacterial effects of NETs or protect the tissue from autodestruction in inadequate NETs release in septic patients.
Mediators of Inflammation 01/2012; 2012:149560. · 3.26 Impact Factor
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ABSTRACT: Displaced tibial eminence fractures require surgical fixation in order to obtain a stable knee joint. Suture fixation with FiberWire(®) seems to be the most favorable therapeutic option. Biomechanical studies show failure of this technique most commonly due to a suture cutout with subsequent fracture of the tibial eminence fragment. The goal of this study is to compare the biomechanical properties of three different techniques of suture fixation using FiberWire(®).
Bone mineral density was evaluated in 18 human knee specimens by pqCT, and three similar groups were formed. A standardized anterior tibial eminence fracture was created, and suture fixation was performed using one of three different techniques in 6 specimens each. Cyclic and destructive testing was conducted.
Significant differences between the three techniques could be shown neither in the cycles needed to achieve a steady state nor in a failure load or initial stiffness. Almost all specimens failed by suture cutout.
The presented modification of the existing technique for suture fixation of tibial eminence fractures did not lead to an increased initial stability nor did it lower the rate of suture cutout. All tested suture techniques showed comparable initial stiffness and failure load.
Knee Surgery Sports Traumatology Arthroscopy 12/2011; 20(10):2088-93. · 2.21 Impact Factor
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Patric Kröpil,
Ahmad R Hakimi,
Pascal Jungbluth,
Carolin Riegger,
Christian Rubbert,
Falk Miese,
Rotem S Lanzman,
Michael Wild,
Alberto Schek,
Axel Scherer, Joachim Windolf,
Gerald Antoch,
Juergen Becker,
Mohssen Hakimi
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ABSTRACT: To evaluate cone beam computed tomography (CBCT) for monitoring of tibial bone defect healing in comparison to histopathological findings.
Circumscribed tibial bone defects were created in 16 mini-pigs and imaging of the tibia was performed on day 42 using a modern CBCT scanner with flat panel detector (PaX-Duo3D, Vatech, Korea). The extent of osseous consolidation including remaining calcium phosphate granules was measured quantitatively by a CBCT volumetry tool using commercially available software (Osirix Imaging software, Pixmeo, Geneva, Switzerland). Volumes of the entire defect (including all pixels), areas of osseous consolidation (density values >2350) and nonmineralized areas (density values <2350) of the defect were determined. The extent of bone regeneration was determined and correlated with the histomorphometrical reference standard. Independently, a visual semiquantitative CBCT-score was applied (4-point scale) to assess bone defect healing.
The extent of osseous consolidation in CBCT volumetry ranged from 14% to 92% (mean, 63.4 ± 17.6%). There was a significant positive correlation between histologically visible newly formed bone and the extent of bone regeneration on CBCT volumetry (r = 0.74-0.79, P < .001). The visual score matched with the volumetric results in 75% of the cases.
CBCT volumetry allows for reliable, noninvasive quantitative monitoring of bone defect healing and correlates significantly with histological findings. CBCT is a promising technique for imaging of peripheral bones suggesting further evaluation in clinical trials.
Academic radiology 12/2011; 19(3):320-5. · 2.09 Impact Factor
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ABSTRACT: Delayed neutrophil apoptosis and overshooting neutrophil activity contribute to organ dysfunction and subsequent organ failure in sepsis. Here, we investigated apoptotic signaling pathways that are involved in the inhibition of spontaneous apoptosis in neutrophils isolated from major trauma patients with uneventful outcome as well as in those with sepsis development. DNA fragmentation in peripheral blood neutrophils showed an inverse correlation with the organ dysfunction at d 10 after trauma in all patients, supporting the important role of neutrophil apoptosis regulation for patient's outcome. The expression of the antiapoptotic Bcl-2 protein members A1 and Mcl-1 were found to be diminished in the septic patients at d 5 and d 10 after trauma. This decrease was also linked to an impaired intrinsic apoptosis resistance, which has been previously shown to occur in neutrophils during systemic inflammation. In patients with sepsis development, delayed neutrophil apoptosis was found to be associated with a disturbed extrinsic pathway, as demonstrated by reduced caspase-8 activity and Bid truncation. Notably, the expression of Dad1 protein, which is involved in protein N-glycosylation, was significantly increased in septic patients at d 10 after trauma. Taken together, our data demonstrate that neutrophil apoptosis is regulated by both the intrinsic and extrinsic pathway, depending on patient's outcome. These findings might provide a molecular basis for new strategies targeting cell death pathways in apoptosis-resistant neutrophils during systemic inflammation.
Molecular Medicine 12/2011; 18(1):325-35. · 3.76 Impact Factor
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ABSTRACT: The management of knee osteoarthritis includes the use of wedged shoe insoles to unload the affected knee compartment. Although the biomechanical effects of shoe insoles on the knee joint are known and described, only little is known about their influence on the pelvis and spine. Therefore, the purpose of this study was to evaluate the effects of different foot positions, such as how they could be achieved by shoe insoles, on pelvic position and spinal posture.
A total of 51 test subjects were measured for this study. The different foot positions (inner and outer margin increase, positive and negative heel height) were simulated with a specially designed stand platform. A rasterstereographic device was used to measure the immediate effects of the simulated foot positions on the pelvic position and spinal posture.
Positive and negative heel heights as well as an increase of the outer margin of the platform led to significant changes of the pelvic tilt. The pelvic torsion also changed significantly during positive heel height changes of 10 and 15 mm and increases of the outer margin of the foot. No significant changes were found between foot position and spinal parameters.
The results of our study support the existence of a kinematic chain, where changes of foot position also led to significant alterations of the pelvic position. Whether these changes could lead to long-term pathologic alterations still needs to be evaluated. However, in our setting, no correlation between foot position and spinal posture changes was found.
Arthritis care & research. 12/2011; 63(12):1758-65.
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ABSTRACT: Surgical treatment of femoral neck fractures is associated with a significant impact on quality of life. The aim of this study was to determine the long-term influence of displaced femoral neck fractures treated by bipolar hemiarthroplasty on the activities of daily living, quality of life and social dependency. We studied 487 geriatric patients treated in the years 1989 to 2003. At the beginning of follow-up in 2004, 166 patients were alive and evaluation was carried out on 145 patients (87.3%) at 91.3 (14 - 244) months postoperatively by a standardized questionnaire. All enrolled patients had been treated with cemented bipolar hemiarthroplasty for a displaced femoral neck fracture. Patients were evaluated concerning their average pre- and postoperative ability to walk, the need for assisting devices, type of residency and the SF-12® Score. Femoral neck fracture and hemiarthroplasty had a significant influence on all recorded aspects of quality of life. Even though almost two thirds of the patients needed assisting devices to walk after surgery, about two thirds returned to their original type of accommodation and the majority reached their original degree of mobility. Compared to a normal population no significant impact was observed on the quality of life measured by the SF-12® score. We consider bipolar hemiarthroplasty an effective treatment option for displaced femoral neck fractures in geriatric patients. Most patients returned to their original type of accommodation and level of mobility, even though the majority required a number of assisting devices to do so.
Hip international: the journal of clinical and experimental research on hip pathology and therapy 11/2011; 21(6):751-6. · 0.34 Impact Factor
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ABSTRACT: Treatment of acute subcutaneous Achilles tendon rupture remains challenging. Whereas the results of conservative and operative treatment are inconsistent, early mobilisation treatment seems to be beneficial. Besides suture repair, operative treatment using adhesives reveals promising results. Our hypothesis was that a gluing technique provides initial stability comparable to sutures.
In a biomechanical study, 18 fresh frozen sheep Achilles tendons were used to compare the biomechanical properties of suture repair using PDS® II and Bunnell's technique to tendon gluing using BioGlue® and Tissucol®. Load to failure testing was performed.
Ultimate failure loads of sutures (146.2 ± 30.8 N) are significantly superior to the techniques using BioGlue® (38.4 ± 18.3 N; p <0.0001) or Tissucol® (4.7 ± 2.5 N; p <0.0001). Interestingly, no significant differences in stiffness were found between the application of BioGlue® and PDS® II.
Suture repair provides significantly superior biomechanical properties compared to the use of both tested adhesives BioGlue® and Tissucol®. Based on the presented data we recommend the use of suture material for open Achilles tendon repair.
International Orthopaedics 09/2011; 36(3):627-32. · 2.03 Impact Factor
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ABSTRACT: The pathophysiology leading to delayed wound healing is complex and efficient therapeutic approaches for accelerated wound healing currently do not exist. We developed a novel drug-eluting platform for the potential use in wound dressings. Here, we report on the potential of eluting ascorbic acid-2-phosphate (ASC-2P), a highly stable variant of ascorbic acid, to induce angiogenesis and to promote collagen synthesis by fibroblasts. The drug-eluting platform device (DEPD) consists of biocompatible polymeric layers comprising polyethylene terephtalate, polyvinyl alcohol (PVA), and polyurethane with PVA as the solvent for ASC-2P. The angiogenic potential of ASC-2P was evaluated in the endothelial cell tube formation assay (TFA) and in the chorion allantoic membrane (CAM) model. Collagen synthesis by ASC-2P-stimulated fibroblasts was determined by Sirius Red staining. ASC-2P significantly induced angiogenesis in five independent TFA and CAM assays and induced collagen synthesis in two different fibroblast cell lines. The eluting kinetics of ASC-2P was determined by the ultraviolet NanoDrop method and the functional 2,2'-Azinobis-(3-ethylbenzthiazolin-6-sulfonic acid) method. Eluting profiles showed a continuous release in the range of biologically effective concentrations >10 days. This is the first report showing the proangiogenic- and collagen-promoting features of ASC-2P. DEPD loaded with ASC-2P ought to be further evaluated as wound dressings or as supplementary pads for topical treatment of delayed wound healing in preclinical studies.
Wound Repair and Regeneration 09/2011; 19(5):597-607. · 2.91 Impact Factor
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ABSTRACT: A tibial nail with fixed-angle locking screws intends to combine the advantages of angular stability and intramedullary stabilization in extraarticular proximal tibial fractures. The goal of this study is to analyze if the angle stable tibial nail (ASN) is biomechanically more stable than an established conventional standard nail (CN).
Two types of nails were compared on a series of ten matched pairs of human tibiae. After setting a proximal tibial defect fracture, the intramedullary stabilized tibiae were axially loaded starting from 100 N increasing in steps of 100 N after every 200 cycles until failure was reached. Failure was defined as deformation of the fracture gap, fracturing of the bone or the implant.
The two types of nails showed no significant difference in terms of maximum tolerated load, maximum cycles repeated or axial deformation of the bone-implant construct. The mean load at failure was 1,365 N for the CN and 1,195 N for the ASN. The mean axial deformation for conventional (19 mm) and angle stable nail (21 mm) did not differ significantly. Slightly less nail or screw loosening was noticed with the fixed-angle nail.
No significant difference in stability between the two compared implants could be demonstrated. A trend could be shown indicating that the rate of nail loosening in the proximal osteotomized part of the bone was lower for the angle stable nail. This trend, however, could not be substantiated statistically.
Archives of Orthopaedic and Trauma Surgery 08/2011; 132(1):57-63. · 1.37 Impact Factor
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ABSTRACT: Purpose of this study was to evaluate the reliability and validity of 4D rasterstereography under dynamic conditions. Therefore simulated anatomical fixed points on a wooden plate were measured during different movements. Seven different motion patterns in all three angles of space were evaluated. The simulated parameter trunk length was measured with an accuracy of 3.58 mm (SD±3.29 mm) and the dimple distance was detected with an accuracy of 0.88 mm (SD±1.04 mm). With this rasterstereographic prototype it is possible to examine dynamically the spinal posture with adequate accuracy.
Computers in biology and medicine 06/2011; 41(6):308-12. · 1.27 Impact Factor
