Timing and Classication of Patellofemoral Osteoarthritis Patients Using Fast Large Margin Classifier

:Surface electromyogram(sEMG)processing and classication can assist neurophysiological standardization and evaluation and provide habitational detection.The timing of muscle activation is critical in determining various medical conditions when looking at sEMG signals.Understanding muscle activation timing allows identication of muscle locations and feature validation for precise modeling.This work aims to develop a predictive model to investigate and interpret Patellofemoral(PF)osteoarthritis based on features extracted from the sEMG signal using pattern classication.To this end,sEMG signals were acquired from ve core muscles over about 200 reads from healthy adult patients while they were going upstairs.Onset,offset,and time duration for the Transversus Abdominus(TrA),Vastus Medialis Obliquus(VMO),Gluteus Medius(GM),Vastus Lateralis(VL),and Multidus Muscles(ML)were acquired to construct a classication model.The proposed classication model investigates function mapping from real-time space to a PF osteoarthritis discriminative feature space.The activation feature space of muscle timing is used to train several large margin classiers to modulate muscle activations and account for such activation measurements.The fast large margin classier achieved higher performance and faster convergence than support vector machines(SVMs)and other state-of-the-art classiers.The proposed sEMG classication framework achieved an average accuracy of 98.8%after 7 s training time,improving other classication techniques in previous literature.

PATELLA AND PATELLOFEMORAL RESURFACING(37 CASES REPORT)

Chondromalacia and patellofemoral osteoarthritis are common diseases that cause pain and disablement of the knee. Conservative therapy is not always effective. Since 1983 we have used isolated polyethylene patellar prosthesis for patella resurfacing of 19 patients with patellofemoral osteoarthritis. After an average of 44. 9 months follow-up, we found the treatment was not as satisfactory as earlier trials. The main reason is the wide erosion of femoral condyle caused by the polyethylene patella. To overcome this shortness, we designed a new type of patellofemoral prosthesis which is named Y-L-Q. From January . 1991 to November. 1 993, we used this prosthesis to treat 16 knees of 13 patients with patellofemoral osteoarthritis. Most of those patients improved both symptomatically and functionally. The good to excellent results rate was 87. 5% (1 4/16 knees) at the time of an average 16 months follow-up. The early results of our experience with patellofemoral resurfacing are encouraging. And extended follow-ups are in progress.

Patellofemoral MRI Alterations Following Single Bundle ACL Reconstruction with Hamstring Autografts Are Associated with Quadriceps Femoris Atrophy

High incidence of patellofemoral pain and patellofemoral joint osteoarthritis was found following anterior cruciate ligament(ACL)reconstruction.The unstability of patellofemoral joint might be an important contribution factor.This study was designed to define the relationship between the unstability of patellofemoral joint and quadriceps femoris atrophy.Twenty patients underwent MRI scan before ACL reconstruction and every two weeks after surgery,until 12 weeks.The merchant’s patellar congruence angle,lateral inclination angle,and quadriceps femoris muscle cross-sectional area were measured and the relationship between the changes of angles and the ratio of quadriceps femoris atrophy was studied by multiple regression analysis.Significant quadriceps femoris atrophy was observed after ACL reconstruction during the follow-up period of 12 weeks.The merchant’s patellar congruence angle and lateral inclination angle significantly changed after surgery.The alterations of the merchant’s patellar congruence angle were significantly correlated with the atrophy ratio of vastus medialis(coefficient=-5.76)and vastus lateralis(coefficient=8.35)during the follow-up period of 12 weeks.The alterations of lateral inclination angle were significantly correlated with the atrophy ratio of vastus medialis(coefficient=20.62),vastus lateralis(coefficient=-11.38)and rectus femoris(coefficient=-0.469)during the follow-up period 12 weeks.To sum up,ACL reconstruction can alleviate the dysfunction of patellofemoral joint to a certain extent.But,the unbalanced atrophy of quadriceps femoris once again destroyed the stability of patellofemoral joint following the operation,which might be one cause of patellofemoral joint pain and early onset of osteoarthritis after ACL reconstruction.So,rehabilitation training that focuses on quadriceps femoris especially the vastus medialis shortly following operation is suggested.

Evaluation of the Surgical Treatment of Patella Fractures in 17 Cases in the Orthopedic-Traumatology Department of the University Hospital Center of Donka, Republic of Guinea

Objectives: To determine the epidemiological, therapeutic and evolutionary aspects. Methodology: This was a retrospective study, from January 1, 2016 to December 31, 2018, on the files of patients aged 16 and over, admitted for patella fractures, treated surgically and followed up in our service. Results: The study involved 17 patients including 15 men (88.24%) and 02 women (11.76%) with an average age of 36.65 years. Workers were the most represented (29.42%);AVP were the leading cause of these fractures (52.94%). The fractures were open in 70.58% of cases. Associated lesions were dominated by femur fractures in 29.42%. Duparc type II was the most encountered bone lesion with 47.06% of cases. All our patients benefited from regional anesthesia. Bracing was the most used surgical treatment in 58.83%;the anterior approach was performed in all our patients. Four (04) cases of knee stiffness, two (02) postoperative infections and skin necrosis complicated the short and medium term consequences. After a two-year follow-up, radiologically one case of pseudarthrosis and one case of patellofemoral osteoarthritis were noted. According to the Bosman score, we found 17.65% excellent, 47.06% good and 35.29% poor functional results. Conclusion: Patella fractures are relatively rare. Treatment is primarily surgical for transverse and/or displaced fractures;Bracing is the osteosynthesis technique of choice. However, knee stiffness, pseudarthrosis and patellofemoral osteoarthritis are not uncommon.

Clinical observation of acupuncture combined with sitting-position knee-adjustment manipulations for patellofemoral arthritis

Objective To observe the efficacy of acupuncture combined with sitting-position knee-adjustment manipulations in treating patellofemoral osteoarthritis.Methods Ninety-two patients with patellofemoral osteoarthritis were randomized into an observation group and a medication group,with 46 cases in each group.The observation group received acupuncture and sitting-position knee-adjustment manipulations,and the medication group received oral celecoxib capsules.After 8-week treatment,changes in the short-form McGill pain questionnaire(SF-MPQ)and Lysholm knee scoring scale(LKSS)scores were observed,and the clinical efficacy was compared.Results The total effective rate was 87.0%in the observation group and 63.0%in the control group;the between-group difference was statistically significant.Before treatment,there were no significant differences in the SF-MPQ score or LKSS score(P>0.05).After 8-week treatment,the SF-MPQ[including pain rating index(PRI),visual analog scale(VAS),and present pain intensity(PPI)]and LKSS scores showed notable changes in both groups(P<0.05);the SF-MPQ and LKSS scores in the observation group were significantly different from those in the control group(P<0.05).Conclusion Combining acupuncture and sitting-position knee-adjustment manipulations can reduce pain and ameliorate joint function in patients with patellofemoral osteoarthritis,producing more significant efficacy than oral celecoxib capsules.