scholarly journals Comparison of in vivo knee kinematics before and after bicruciate-stabilized total knee arthroplasty during squatting

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Masato Kiyohara ◽  
Satoshi Hamai ◽  
Hirotaka Gondo ◽  
Hidehiko Higaki ◽  
Satoru Ikebe ◽  
...  
Keyword(s):  
Rotation Angle ◽  
Knee Kinematics ◽  
Significant Difference ◽  
Before And After ◽  
Rotational Mismatch ◽  
Total Knee ◽  
Skeletal Kinematics ◽  
Functional Extension ◽  
Mismatch Angle

Abstract Background No studies have directly evaluated kinematic changes during squatting before and after bicruciate-stabilized total knee arthroplasty (BCS-TKA) with the dual cam-post mechanism and asymmetric surfaces. This study investigated the effect of BCS-TKA on changes to pre- and postoperative skeletal knee kinematics, to identify factors associated with postoperative skeletal kinematic parameters. Methods Seventeen knees in 17 patients were prospectively recruited before primary TKA for advanced medial knee osteoarthritis. Subjects underwent BCS-TKA and were evaluated more than 1 year postoperatively. In vivo dynamic skeletal knee kinematics were evaluated using periodic radiographic images collected during squatting to quantify the tibiofemoral functional extension/flexion angle, anteroposterior (AP) translation, and axial rotation angle using image-matching techniques. Rotational alignments of femoral and tibial components were measured postoperatively using computed tomography images. Results The pre- and postoperative tibiofemoral functional extension/flexion angles during squatting were 12.2° ± 6.7°/100.1° ± 16.8° and 9.6° ± 8.6°/109.4° ± 16.8°, respectively, with a significant difference in flexion angle (p < .05). Total AP translation was significantly larger postoperatively than preoperatively (10.8 mm ± 3.7 mm vs. 14.4 mm ± 4.2 mm, respectively; p < .05). The pre- and postoperative total rotation angles were 6.6° ± 3.0° and 6.4° ± 3.7°, respectively, indicating no significant difference. The pre- and postoperative tibiofemoral functional flexion angles were significantly associated with each other (p = .0434, r = .49). The postoperative total rotation angle was significantly smaller when the total component rotational mismatch angle between the femoral and tibial components was above 5° vs. below 5° (4.6° ± 2.7° vs. 8.3° ± 3.9°, respectively; p < .05). Conclusions BCS-TKA significantly increased the tibiofemoral functional flexion angles, with larger AP translation postoperatively. Both preoperative skeletal kinematics and surgical techniques affected the skeletal kinematics of the replaced knee. A total component rotational mismatch angle greater than 5° significantly decreased postoperative total knee rotation during squatting.

In Vivo Comparison of Knee Kinematics Before and After High-Flexion Posterior Cruciate-Retaining Total Knee Arthroplasty

2010 ◽  
Vol 25 (6) ◽  
pp. 964-969 ◽  
Author(s):  
Atsushi Kitagawa ◽  
Nobuhiro Tsumura ◽  
Takaaki Chin ◽  
Kazuyoshi Gamada ◽  
Scott A. Banks ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Knee Kinematics ◽  
Cruciate Retaining ◽  
High Flexion ◽  
Before And After ◽  
Total Knee

Effect of Gait on Patellofemoral Mechanics

2008 ◽  
Author(s):  
Jeffrey E. Bischoff ◽  
Justin S. Hertzler
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Clinical Studies ◽  
Patellofemoral Joint ◽  
Knee Kinematics ◽  
Component Design ◽  
Total Knee ◽  
The Impact ◽  
Reconstructed Knee

Computational modeling of the reconstructed knee is an important tool in designing components for maximum functionality and life. Utilization of boundary conditions consistent with in vivo gait loading in such models enables predictions of knee kinematics and polyethylene damage [1–4], which can then be used to optimize component design. Several recent clinical studies have focused on complications associated with the patellofemoral joint [5–6], highlighting the need to better understand the mechanics of this compartment of total knee arthroplasty (TKA). This study utilizes a computational model to characterize the impact of gait loading on the mechanics of the patella in TKA.

scholarly journals Decrease in Platelet Aggregability after Total Oophorectomy

1977 ◽  
Author(s):  
H. Yamazaki ◽  
T. Motomiya ◽  
M. Sonoda ◽  
N. Miyagawa
Keyword(s):  
Platelet Count ◽  
Clinical Evidence ◽  
Coulter Counter ◽  
Control Group ◽  
Bilateral Oophorectomy ◽  
Platelet Volume ◽  
Platelet Aggregability ◽  
Significant Difference ◽  
Before And After

Substantial clinical evidence indicates that large doses of estrogen frequenly result in thromboembolic disorders. Effects of estrogen on platelet aggregability were examined in women with uterine myoma before and after oophorectomy. Bilateral oophorectomy on 15 cases (48.7+0.12 yrs, mean+SE) and unilateral or no oophorectomy on 18 cases (control group : 42.2+0.18 yrs) were performed with myomectomy of the uterus. On one day before and one day, one week and one month after the operation performed, their platelet count by Coulter counter, platelet volume by Coulter channelyzer and platelet aggregability by Sienco aggregometer were measured. 24 hrs total estrogen in urine was also determined. In the control group, platelet counts were 85.1+ 4.9 % of the preoperated value one day after, 127.9+9.0 % one week after and 98.1+7.6 % one month after the operation. In the bilateral oophorectomy group, these were 82.4+5.2 % one day after, 124.0+4.7 % one week after and 96.1+4.8 % one month after. Both the groups showed the same change. Platelet aggregability by 3 μM ADP were 76.9+14.3 % one day after, 203.0+57.1 % one week after and 193.4+59.0 % one month after in the control, while 55.0+13.6 % one day after, 102.5+12.9 % one week after and 60.6+14.7 % one month after the operation in the total oophorectomy group. There was a statistically significant difference in the values obtained one month after the operation between the groups (p<0.05). Characteristic changes in platelet volumes were also observed. A significant correlation was observed between the platelet aggre-gabilities and the daily urinary estrogen excretion levels. The above results suggest that estrogen may enhance platelet aggregability in vivo.

Knee kinematics after cruciate retaining highly congruent mobile bearing total knee arthroplasty: An in vivo dynamic RSA study

The Knee ◽  
2020 ◽  
Vol 27 (2) ◽  
pp. 341-347 ◽  
Author(s):  
Umberto Cardinale ◽  
Laura Bragonzoni ◽  
Marco Bontempi ◽  
Domenico Alesi ◽  
Tommaso Roberti di Sarsina ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Knee Kinematics ◽  
Mobile Bearing ◽  
Cruciate Retaining ◽  
Total Knee

Effect of Single Dose In Vivo Propranolol Therapy on In Vitro Adhesion of Human SS RBC.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1234-1234 ◽  
Author(s):  
Laura M. De Castro ◽  
Jude C. Jonassaint ◽  
Jennifer G. Johnson ◽  
Milena Batchvarova ◽  
Marilyn J. Telen
Keyword(s):  
Safety Data ◽  
Study Drug ◽  
Flow Chamber ◽  
In Vivo Studies ◽  
Dependent Manner ◽  
Number Of Patients ◽  
Significant Difference ◽  
Before And After

Abstract Sickle red blood cells (SS RBC) are abnormally adhesive to both endothelial cells (ECs) and components of the extracellular matrix (ECM). Epinephrine (epi) has been shown to elevate cAMP in SS RBC and increase adhesion of SS RBC to ECs in a protein kinase A-dependent manner. In vitro and in vivo studies performed in our lab have led to the hypothesis that adrenergic stimuli such as epi may initiate or exacerbate vaso-occlusion and thus contribute to the association of vaso-occlusive events with physiologic stress. We are conducting a prospective, dose-escalation pilot clinical study to investigate whether in vivo administration of one dose of propranolol either down-regulates baseline SS RBC adhesion in vitro or prevents its upregulation by epi. In addition, this study will provide additional safety data regarding the use of propranolol in normotensive patients with sickle cell disease (SCD). Figure Figure To date, we have completed the first two dose cohorts. 11 subjects (9 SS and 1 Sβ° thalassemia; 7 females, 3 males) have participated. No severe adverse events were noted. Cohorts 1 and 2 had mean pre-propranolol blood pressure (BP) of 116 (5.9 SD)/ 60.4 (3.98 SD) and 106.8 (4.68 SD)/ 58 (3.9 SD), respectively; this difference was not statistically significant. Minimal and asymptomatic changes in BP were noted in both cohorts after drug administration, with biphasic systolic and diastolic BP nadirs at 45 and 240 minutes. No clinically significant changes in heart rate were observed. Adhesion studies were performed using a graduated height flow chamber on the day of RBC collection. RBC adhesion to ECs was studied before and after epi stimulation and was measured at sheer stresses ranging from 1 to 3 dyne/cm2. Baseline adhesion measurements were validated by comparing percent (%) adhesion assayed at 2 different times within 7 days—at screening and before propranolol dose on the study drug day. We observed no significant difference in adhesion at the 2 different time points without propranolol. Comparison of % adhesion of epi-stimulated RBC to ECs before and 1 hour after propranolol showed that propranolol given in vivo significantly inhibited both non-stimulated and epi-stimulated SS RBC adhesion (p=0.04 and p=0.001, respectively). Lastly, comparison of SS RBC adhesion at both drug doses confirmed the drug-related inhibition of adhesion (p&lt;0.004). We conclude that propranolol administered in vivo decreases SS RBC baseline adhesion to ECs and substantially abrogates epi-stimulated adhesion to ECs, as measured in vitro. Although we have thus far studied only a small number of patients and low propranolol doses, we expect to confirm these results with the 3rd cohort, in which a higher dose of propranolol will be used. If our findings continue to show that propranolol can decrease both SS RBC baseline and epi-stimulated adhesion to ECs, study of propranolol on a larger scale would be warranted in order to ascertain its safety and efficacy as an anti-adhesive therapy in SCD.

scholarly journals In vivo knee kinematics during high flexion after a posterior-substituting total knee arthroplasty

2009 ◽  
Vol 34 (4) ◽  
pp. 497-503 ◽  
Author(s):  
Angela L. Moynihan ◽  
Kartik M. Varadarajan ◽  
George R. Hanson ◽  
Sang-Eun Park ◽  
Kyung Wook Nha ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Knee Kinematics ◽  
High Flexion ◽  
Total Knee ◽  
In Vivo Knee Kinematics

Passive Knee Kinematics Before and After Total Knee Arthroplasty

2008 ◽  
Vol 23 (1) ◽  
pp. 57-60 ◽  
Author(s):  
William M. Mihalko ◽  
Mounawar Ali ◽  
Matthew J. Phillips ◽  
Mary Bayers-Thering ◽  
Kenneth A. Krackow
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Knee Kinematics ◽  
Before And After ◽  
Total Knee

Aminophylline and human diaphragm strength in vivo

1990 ◽  
Vol 68 (6) ◽  
pp. 2591-2596 ◽  
Author(s):  
R. D. Levy ◽  
S. Nava ◽  
L. Gibbons ◽  
F. Bellemare
Keyword(s):  
Motor Units ◽  
Normal Subjects ◽  
Acute Administration ◽  
Transdiaphragmatic Pressure ◽  
Gastric Pressure ◽  
Significant Difference ◽  
Before And After ◽  
Normal Human ◽  
Twitch Characteristics

The transdiaphragmatic pressure (Pdi) twitch response to single shocks from supramaximal bilateral phrenic nerve stimulation was studied before and after acute intravenous infusions of aminophylline [14.9 +/- 3.1 (SD) micrograms/ml] in nine normal subjects. Stimulation was performed with subjects in the sitting position against an occluded airway from end expiration. Baseline gastric pressure and abdominal and rib cage configuration were kept constant. There was no significant difference in peak twitch Pdi from the relaxed diaphragm between control (38.8 +/- 3.3 cmH2O) and aminophylline (40.2 +/- 5.2 cmH2O) experiments. Other twitch characteristics including contraction time, half-relaxation time, and maximum relaxation rate were also unchanged. The Pdi-twitch amplitude at different levels of voluntary Pdi was measured with the twitch occlusion technique, and this relationship was found to be similar under control conditions and after aminophylline. With this technique, maximum Pdi (Pdimax) was calculated as the Pdi at which stimulation would result in no Pdi twitch because all motor units are already maximally activated. No significant change was found in mean calculated Pdimax between control (146.9 +/- 27.0 cmH2O) and aminophylline (149.2 +/- 26.0 cmH2O) experiments. We conclude from this study that the acute administration of aminophylline at therapeutic concentrations does not significantly affect contractility or maximum strength of the normal human diaphragm in vivo.

The Effect of Joint Line Elevation on In Vivo Knee Kinematics in Bicruciate Retaining Total Knee Arthroplasty

2021 ◽  
Author(s):  
Christian Klemt ◽  
Anand Padmanabha ◽  
Venkatsaiakhil Tirumala ◽  
Evan J. Smith ◽  
Young-Min Kwon
Keyword(s):  
Negative Correlation ◽  
Knee Kinematics ◽  
Significant Negative Correlation ◽  
Significant Loss ◽  
Maximum Flexion ◽  
Sit To Stand ◽  
Total Knee ◽  
In Vivo Knee Kinematics ◽  
Bcr Tka

AbstractPrior studies have reported a negative effect on both clinical outcomes and patient-reported outcome measures (PROMS) following joint line elevation (JLE) in cruciate-retaining (CR) total knee arthroplasty (TKA) and posterior stabilized (PS) TKA designs. This experimental study was aimed to quantify the effect of JLE on in vivo knee kinematics in patients with bicruciate retaining (BCR) TKA during strenuous activities. Thirty unilateral BCR TKA patients were evaluated during single-leg deep lunge and sit-to-stand using a validated combined computer tomography and dual fluoroscopic imaging system. Correlation analysis was performed to quantify any correlations between JLE and in vivo kinematics, as well as PROMS. There was a significant negative correlation between JLE and maximum flexion angle during single-leg deep lunge (ρ = −0.34, p = 0.02), maximum varus joint angles during single-leg deep lunge (ρ = −0.37, p = 0.04), and sit-to-stand (ρ = −0.29, p = 0.05). There was a significant negative correlation between JLE and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (ρ = −0.39, p = 0.01) and knee disability and osteoarthritis outcome score physical function (KOOS-PS; ρ = −0.33, p = 0.03). The JLE that yields a significant loss in PROMS and maximum flexion angles were 2.6 and 2.3 mm, respectively. There was a linear negative correlation of JLE with both in vivo knee kinematics and PROMS, with changes in JLE of greater than 2.6 and 2.3 mm, leading to a clinically significant loss in PROMS and maximum flexion angles, respectively, suggesting an increased need to improve surgical precision to optimize patient outcomes following BCR TKA.

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