Correlation analysis between imaging classification of varus knee osteoarthritis and axis angle of tibiofemoral and patellofemoral joints / 中国骨伤

OBJECTIVE@#To explore correlation between imaging classification of knee osteoarthritis (KOA) and axis angle of tibiofemoral and patellofemoral joints.@*METHODS@#A retrospective analysis of 739 middle-aged and elderly patients with KOA (1 026 knee joints) who underwent vertical X-ray examination of both lower limbs and lateral knee joints from September 2018 to December 2020. Among them, 63 patients with K-L 0 grade (95 knee joints), 100 patients with K-L 1 grade (130 knee joints), 161 patients with K-L 2 grade (226 knee joints), 187 patients with K-L 3 grade (256 knee joints), and 228 patients of K-L 4 grade (319 knee joints). According to relative position of knee joint center and line between hip joint center and ankle joint center, the affected knee was divided into varus group(844 knees joints) and valgus group (182 knees joints). According to Install-Salvati method, the affected knee was divided into three groups, such as high patella (patella height>1.2 mm, 347 knees joints), median patella (patella height ranged from 0.8 to 1.2 mm, 561 knees joints), and low patella (patella height<0.8 mm, 118 knees joints). Lower femur angle, upper tibia angle, femoral neck shaft angle, femoral tibial angle, joint gap angle, hip-knee-ankle angle, patella-femoral angle and patella height among different groups were observed and compared.@*RESULTS@#(1) In varus KOA group, there were statistical differnces in hip-knee-ankle angle, tibiofemoral angle, lower femoral angle, upper tibial angle, joint space angle, and femoral neck shaft angle of patients with different K-L grades (P<0.05). Hip-knee-ankle angle, tibiofemoral angle, lower femoral angle, upper tibial angle, joint space angle and K-L grade were significantly positively correlated at 0.01(P<0.05);femoral neck shaft angle and K-L grade showed negative correlation at 0.01(P<0.05). (2) In valgus KOA group, hip-knee-ankle angle, there were statistical differences in tibiofemoral angle, inferior femoral angle, superior tibial angle, joint space angle, and femoral neck shaft angle of patients with different K-L grades(P<0.05). Hip-knee-ankle angle, tibiofemoral angle, lower femoral angle, upper tibial angle, and femoral neck shaft angle showed negative correlation with K-L grades at level of 0.01 (P<0.05);joint gap angle and K-L grades showed significantly positive correlation at level of 0.01(P<0.05). (3) In high patella group, there were statistically differences in patellar height and patellar femoral angle of different K-L grades(P<0.05);there were no statistical difference in patella height and patellar femoral angle of different K-L grades in median patella group. There was no significant difference in patella heightin low patella group with different K-L grades(P>0.05), and there was statistical difference in patellofemoral angle(P<0.05). Patellar height and patella-femoral angle of high patella group were significantly positively correlated with K-L grades at the level of 0.01 (P<0.05);patella height and patella-femoral angle were not correlated with K-L grades in median patella group(P>0.05). There was no correlation between height of patella and K-L grade in low patella group (P>0.05). There was significant negative correlation between patella-femoral angle and K-L grade at level of 0.05 (P<0.05).@*CONCLUSION@#Inferior femoral angle, tibiofemoral angle, joint gap angle, hip-knee-ankle angle, femoral neck shaft angle and high patella are related to K-L classification of varus KOA, which could be used for early diagnosis and provide objective data for efficacy analysis of conservative treatment.

Prevalence of chondromalacia patella according to patella type and patellofemoral geometry: a retrospective study

Abstract BACKGROUND: The relationships between the morphometric structure of the patellofemoral joint, patella type and chondromalacia patella are still a matter of debate. OBJECTIVE: To identify the prevalence of chondromalacia patella by determining the patella type and making patellofemoral morphometric measurements. DESIGN AND SETTING: Retrospective cohort study in an orthopedics and traumatology clinic in Turkey, conducted between June 2017 and November 2019. METHODS: This study involved 562 knees of 522 patients with anterior knee pain (246 males and 316 females; mean age 46.59 years). The patients were grouped according to presence of chondromalacia patella (group I) or absence of chondromalacia patella (group II). The patella type, lateral trochlear inclination, medial trochlear inclination, trochlear angle, sulcus angle, patellar tilt and Insall-Salvati index were assessed. Group comparisons were made using chi-square tests or Student t tests. The r value was used to determine the magnitude of relationships between pairs of variables. RESULTS: Among the 562 knees evaluated, 265 (50.71%) presented type I patella, 195 (36.7%) type II, 100 (12.3%) type III and 2 (0.3%) type IV. Group I consisted of 448 knees and group II consisted of 114 knees. Significant differences were found between the groups in terms of age, gender, patella type and lateral inclination angles (P < 0.05). CONCLUSION: Detecting the patella type and making lateral inclination measurements in patients with anterior knee pain are of great importance for diagnosing suspected chondromalacia patella, particularly in the early degenerative period.

Early- and mid-term clinical outcomes of patellofemoral arthroplasty / 中华骨科杂志

Objective:To investigate the early- and mid-term clinical, functional and radiographic outcomes of patellofemoral arthroplasty (PFA).Methods:A retrospective analysis was conducted in 64 patients (80 knees) who suffered from severe patellofemoral osteoarthritis (PFOA) and underwent PFA from January 2013 to December 2020. These patients were aged 60.50±8.82 (range from 27 to 82) years, including 9 males (12 knees) and 55 females (68 knees). All enrolled individuals presented typical PFOA. Unilateral PFA was performed in 48 cases, bilateral PFA in 16 cases, including one-stage PFA in 9 cases and two-stage PFA in 7 cases. The visual analogue scale (VAS), Hospital for Special Surgery (HSS) knee score and Oxford knee score (OKS) of patients with more than 5 years' follow-up were assessed to evaluate the clinical effects of PFA at the time before surgery, 1 year and 5 years after surgery. In addition, the patellar tilt angle (PTA) and hip-knee-ankle (HKA) angle were measured and analyzed to evaluate the improvement of patellar tracking and progression of tibiofemoral osteoarthritis, based on axial X-ray imaging (skyline view) of knee and the full length standing X-ray imaging of the lower limbs at before surgery and 5 years after surgery. Meanwhile, the complications of all patients that related to the operation were recorded.Results:A total of 64 patients were followed up for 4.31±1.79 (range, 1.5 to 8.2) years. Twenty-five patients (32 knees) who followed up more than 5 years were analyzed. The VAS, HSS and OKS improved from 5.91±0.82, 68.06±6.03 and 21.22±3.46 preoperatively to 0.88±1.01, 90.09±3.30 and 39.06±3.37 at 1 year after surgery, and to 0.41±0.76, 94.53±2.99 and 42.13±3.17 at 5 years after surgery, respectively ( F=89.38, 81.47, 56.73, P<0.001). Additionally, comparing to the preoperative radiological data, the patellar tract was improved with the PTA decreased from 8.21°±3.14° preoperatively to 3.58°±4.48°at 5 years after surgery ( t=4.96, P<0.001). The HKA angle changed from 179.01°±1.43° preoperatively to 178.77°±1.67° at 5 years follow up ( t=1.71, P=0.096). There was no case of prosthesis loosening or wear and no case of obvious progression of tibiofemoral osteoarthritis that needed revision in all patients. Conclusion:Satisfied early- and mid-term clinical outcomes could be achieved by PFA in treating severe PFOA patients. PFA could relieve pain and improve function of knee joint.

Risk factors for patellar clunk syndrome after total knee arthroplasty without patellar surface replacement / 中华创伤骨科杂志

Objective:To analyze the risk factors for patellar clunk syndrome after total knee arthroplasty (TKA) without patellar surface replacement.Methods:Retrospectively analyzed were a total of 222 patients who had undergone TKA without patellar surface replacement at Department of Joint Surgery, The Second Hospital of Shanxi Medical University from June 2020 to June 2021. There were 43 males and 179 females, and 38 cases of rheumatoid arthritis and 184 cases of arthritis. They were divided into a patellar clunk syndrome group ( n = 56) and a non-patellar clunk syndrome group ( n = 166) according to the occurrence of patellar clunk after TKA. The incidence of early patellar clunk syndrome after TKA was 25.2% (56/222). The patient gender, arthritis type, prosthesis type, postoperative range of knee motion, postoperative patellar thickness, Insall-Salvati index, postoperative joint line height, lower extremity muscle strength, and the distance from the tibial plateau to the patellar tendon were recorded. The risk factors for patellar clunk syndrome were determined by univariate analysis and logistic analysis. Results:The univariate analysis showed significant differences between the 2 groups in prosthesis type, postoperative joint line height, postoperative lower extremity muscle strength, and the distance from the tibial plateau to the patellar tendon ( P < 0.05). The logistic analysis showed that the posterior cruciate substituting (PS) prosthesis was an independent risk factor compared with the cruciate-retaining (CR) prosthesis ( OR = 2.791, 95% CI: 1.411 to 5.521, P = 0.003), and the increased lower extremity muscle strength was an independent protective factor ( OR = 0.295, 95% CI: 0.148 to 0.587, P = 0.001). Conclusions:The incidence of patellar clunk syndrome is relatively high. The PS prosthesis may be an independent risk factor relative to the CR prosthesis. As the increased lower extremity muscle strength may be an independent protective factor, the recovery and strengthening of the muscle strength after TKA require more attention.

Radiographic study of the patellofemoral axial alignment with episodic patellar dislocation / 中华创伤杂志

Objective:To explore the diagnostic performance of patella-tilt angle and congruence angle in episodic patellar dislocation (EPD) and the quantitative measurements of the patellar and femoral axial parameters as well as their correlation with and contributions to the patellofemoral joint alignment with the knee extended.Methods:A case control study was conducted to analyze the radiological data of EPD patients (EPD group, n=106) and patients without patellar instability (control group, n=106) admitted to Sixth People′s Hospital Affiliated to Shanghai Jiao Tong University from January 2016 to December 2019. Each group consisted of 55 females and 51 males with the age range of 14-45 years [(23.0±5.3)years], showing 1∶1 match. Axial parameters included patellar parameters (patellar width, patellar thickness, Wiberg angle and Wiberg index), femoral parameters [trochlear sulcus angle, trochlear sulcus depth, trochlear sulcus height, trochlear width ratio (lateral/medial), trochlear height ratio (lateral/medial), lateral trochlear inclination and trochlear groove medialization], and patellofemoral joint parameters (patellar tilt angle and congruence angle). The receiver operating characteristic (ROC) curve of patellofemoral joint parameters for the prediction of EPD was analyzed. Univariate analysis was performed to determine the difference of those axial parameters between the two groups. Pearson correlation analysis was used to identify the correlation between those bony parameters and patellofemoral joint parameters. Stepwise regression model was further established to determine the influencing factors and corresponding contributions for patellofemoral joint parameters. Results:When the optimal cut-off values of patellar tilt angle and congruence angle were 17.2° and 25.5°, the area under the ROC curve (AUC) for predicting EPD was 0.91 (95% CI 0.87-0.95, P<0.01) and 0.92 (95% CI 0.87-0.95, P<0.01), and the Youden index was 0.745 (sensitivity=83.96%, specificity=90.57%) and 0.717 (sensitivity=81.13%, specificity=90.57%). Univariate analysis showed that Wiberg index, femoral parameters and patellofemoral joint parameters were significantly different between the two groups (all P<0.01). For all patients, Pearson correlation analysis showed that patellar tilt angle was moderately to strongly correlated with Wiberg index, trochlear sulcus angle, trochlear sulcus depth, trochlear width ratio (lateral/medial), trochlear height ratio (lateral/medial) and lateral trochlear inclination ( r=0.51, 0.41, -0.62, 0.43, -0.49, -0.65, all P<0.01) and that congruence angle has a moderate correlation with trochlear sulcus angle, trochlear sulcus depth, trochlear width ratio (lateral/medial) and lateral trochlear inclination ( r=0.43,-0.59,0.38,-0.51, all P<0.01). For all patients, Stepwise regression model analysis showed that lateral trochlear inclination, trochlear sulcus depth, trochlear sulcus angle, Wiberg index and trochlear height ratio (lateral/medial) could explain 60% of the variation of patellar tilt angle ( R 2=0.60, P<0.01) and that trochlear sulcus depth, lateral trochlear inclination, trochlear groove medialization, trochlear sulcus angle and Wiberg index could explain 44% of the variation of congruence angle ( R 2=0.44, P<0.01). Conclusions:The patellar tilt angle and congruence angle are reliable quantitative indicators representing patellofemoral axial alignment, with a good diagnostic performance for EPD. Variations in the patellar and femoral bony structures of EPD patients are related to the patellofemoral axial alignment, with the axial parameters differently contributing to the patellofemoral alignment.

Clinical results of medial patellofemoral ligament reconstruction / Resultados clínicos da reconstrução do ligamento patelofemoral medial

ABSTRACT Objective: To assess clinical results of patients who underwent medial patellofemoral ligament (MPFL) reconstruction after a minimum of two years of follow-up. Methods: Patients' medical records were assessed for residual instability, patient satisfaction, and post-operative functional outcomes. Results: Fifty-one patients were analyzed, out of which 56.87% were women. Patients' mean age was 30.8 years (16 to 57 years). The mean follow-up time was 68.7 months (37 to 120 months). Length between first dislocation and surgery was less than 1 year for 58.82% of patients, between 1 and 5 years for 37.25%, and over 5 years for 3.93%. Patients showed a high degree of satisfaction (96.08% would undergo surgery again), with recurrence rate of 11.76%. Twenty-two patients reported knee symptoms, including pain from movements (72.72%), weakness (18.18%), constant pain (13.63%), and crepitus (4.54%). Considering dissatisfied patients, patients with dislocation recurrence, and patients with symptoms, five cannot practice physical activity, out of which only three blame their knee. Conclusion: MPFL reconstruction showed a recurrence rate of 11.7%, with high patient satisfaction, good functional results, and high rate of return to sports, after a minimum of two years of follow-up. Level of Evidence IV, Case Series.

RESUMO Objetivo: Avaliar o resultado clínico de pacientes submetidos à reconstrução do ligamento patelofemoral medial (LPFM), acompanhados por mínimo de dois anos. Métodos: Avaliação de prontuários para informações sobre instabilidade residual, satisfação do paciente e resultado funcional pós-operatório. Resultados: Foram analisados 51 pacientes. 56,87% do sexo feminino e média etária 30,8 anos (16 a 57). Tempo médio de acompanhamento de 68,7 meses (37 a 120). Intervalo entre primeira luxação e cirurgia foi menos de 1 ano em 58,82%, entre 1 e 5 anos em 37,25% e mais de 5 anos para 3,93%. Os pacientes apresentaram alto grau de satisfação (96,08% fariam a cirurgia novamente), com 11,76% de recidiva. Houve persistência de sintomas em 22 pacientes, sendo dor ao movimento o principal (72,72%), seguido de fraqueza (18,18%), dor constante (13,63%) e crepitações (4,54%). Somando os pacientes insatisfeitos aos que tiveram recidiva da instabilidade e os sintomáticos, 5 não conseguem praticar atividade física, mas apenas 3 por causa do joelho. Conclusão: A reconstrução isolada do LPFM demonstrou índice de recidiva de 11,7%, com alto nível de satisfação dos pacientes, ótimos resultados funcionais e alta taxa de retorno ao esporte, em acompanhamento mínimo de 2 anos. Nível de Evidência IV, Série de Casos.

Update on Patellar Instability / Atualização em instabilidade patelar

Abstract Patellar instability is a multifactorial clinical condition that affects a significant number of patients and occurs due to morphological variations of the joint and patellofemoral alignment. The present literature review study aimed to identify and summarize current concepts on patellar instability, in relation to associated risk factors, diagnostic criteria, and the benefits and risks of conservative and surgical treatments. For this purpose, a search was conducted in the following electronic databases: MEDLINE (via Pubmed), LILACS and Cochrane Library. It is concluded that the accurate diagnosis depends on the detailed clinical evaluation, including the history and possible individual risk factors, as well as imaging exams. The initial treatment of patellar instability is still controversial, and requires the combination of conservative and surgical interventions, taking into consideration both soft tissues and bone structures, the latter being the most common reason for choosing surgical treatment, especially lateral patellar instability.

Resumo A instabilidade patelar é uma condição clínica multifatorial, que acomete um número expressivo de pacientes, ocorrendo devido a variações anatómicas, morfológicas da articulação e do alinhamento patelofemoral. O presente estudo de revisão e atualização da literatura teve como objetivos identificar e sumarizar os conceitos atuais sobre instabilidade patelar em relação aos fatores de risco associados, os critérios diagnósticos e os benefícios e riscos dos tratamentos conservador e cirúrgico. Para tanto, foi realizado um levantamento nas bases de dados eletrónicas MEDLINE (via Pubmed), LILACS e Cochrane Library. Conclui-se que o diagnóstico preciso depende da avaliação clínica detalhada, incluindo o histórico e possíveis fatores de risco individuais, além de exames de imagem. O tratamento inicial da instabilidade patelar é ainda controverso, e requer a combinação de intervenções conservadoras e cirúrgicas, levando em consideração tanto os tecidos moles quanto as estruturas ósseas, sendo estas últimas a razão mais comum para a escolha do tratamento cirúrgico, principalmente instabilidade patelar lateral.

Finite element analysis on stress concentration improvement in patellofemoral joint by releasing lateral patellar retinaculum with stiletto needle based on the theory of Jinshugu() / 中国骨伤

OBJECTIVE@#To study mechanism of improvement of stress concentration on patellofemoral joint by stiletto needle releasing lateral patellar retinaculum guided by the theory of Jinshugu() and based on the finite element model of knee joint. and to elucidate the biomechanical mechanism of stiletto needle releasing changing patellar trajectory and reducing patellofemoral joint pressure.@*METHODS@#CT data of knee joint from a normal male (aged 29, heighted 171 cm, weighted 58 kg) was selected. Starting with construction of three-dimensional model of knee joint by using finite element software, the finite element model of knee joint with complete tendonand bone structures were established through several steps, such as geometric reconstruction, reverse engineering, meshing, material assignment and loading analysis. The loading condition was set as 500 N load on knee joint, and the average tensile stress of quadriceps femoris tendon was about 200 N. To simulate the release of lateral patellar retinaculum by stiletto needle at 30 and 90 position of knee flexion in finite element model separately, and to compare the improvement of stress concentration of patellofemoral joint by stiletto needle intervention under different knee flexion conditions.@*RESULTS@#The peak stress of patellofemoral joint and tibiofemoral joint decreased after stiletto needle releasing of patellofemoral lateral retinaculum compared with before intervention, which was(1) knee flexion at 30 degrees:patellar cartilage decreased by 0.498 MPa (decreased 9.06%), femoral trochlea decreased by 0.886 MPa(decreased 16.27%);(2) knee flexion at 90 degrees:patellar cartilage decreased by 0.558 MPa (decreased 8.6%), femoral trochlea decreasedby 0.607 MPa (decreased 9.94%).@*CONCLUSION@#Releasing lateral patellofemoral retinaculum with stiletto needle could effectively alleviate the stress concentration of patellofemoral joint and reduce local stress peak value, which it is helpful to improve patellar trajectory and make stress distribution more uniform.

Systematic Review on Studies of in vivo Patellofemoral Joint Kinematics / 医用生物力学

Patellar tracking disorder is recognized as one of the major causes of the pathophysiological mechanism in patellofemoral pain syndrome. This paper reviewed the results of patellofemoral kinematic analyses and summarized the motion characteristics of six-degrees-of-freedom (6DOF) of patellofemoral joints under different functional activities. Patella has a relatively unified trend in lateral, anterior and posterior translation, tilt and flexion. However, different measurements limit an in-depth comparison between studies. In the future, widely applying magnetic resonance(MRI) or/and dual fluoroscopic imaging system (DFIS), standardizing the establishment of coordinate system or definition and use of morphological parameters, and increasing sample size will contribute to explicating the 6DOF motion characteristics of patellofemroal joints in vivo and improve the clinical evaluation on kinematic function of patellofemroal joints.

Effect of different femoral tunnel locations on patellofemoral joint during single-bundle anterior cruciate ligament reconstruction / 中国组织工程研究

BACKGROUND: Studies have shown that arthroscopic single-bundle anterior cruciate ligament reconstruction can restore the forward stability of the knee joint, but the rotational stability of the knee joint and the matching degree with the patellofemoral joint are affected by the central position of the femoral and tibial tunnels. OBJECTIVE: To investigate the relationship between the location of different femoral tunnel centers and patellofemoral articulation and cartilage conditions in young and middle-aged patients with anterior cruciate ligament reconstruction, and to carry out the correlation analysis of patient study factors to further explore the location of the femoral tunnel with the least influence on the patellofemoral joint. METHODS: Seventy patients with anterior cruciate ligament rupture were diagnosed by preoperative MRI, physical examination and intraoperative arthroscopy. All patients were divided into quasi-isometric group and quasi-anatomical group according to the parity of random numbers. In the quasi-isometric group, a Kirschner needle was inserted 7 mm distal to the apex of the lateral wall of the intervertebral fossa using a femoral locator. In the quasi-anatomical group, the Kirschner needle was inserted at the lateral wall of the intercondylar fossa and at the foot print center of the original anterior cruciate ligament. The central coordinates of the femoral tunnel were evaluated on the near-far-front-rear plane based on a standardized grid system, while the central coordinates of the tibial tunnel was evaluated on the anterior-posterior-inner-outer plane, labeled as quadrant Y% and quadrant X%. By comparing the baseline data of patients in the two groups, the difference of lateral patellofemoral angle (LPFA), the difference of cartilage quantitative T2 value, and the correlation between various research factors, the surgical operators were further guided to carry out clinical practice. The implementation of the study protocol complied with the relevant ethical requirements of the First Affiliated Hospital of Anhui Medical University, and all patients signed an informed consent form prior to the participation in the trial. RESULTS AND CONCLUSION: There was no significant difference in baseline data between the two groups, but a significant difference in LPFA existed between the two groups, (0.57±0.33)° in the quasi-anatomical group vs. (1.55±0.36)° in the quasi-isometric group (P<0.001). The T2 values of medial patella, lateral patella and trochlear cartilage in the quasi-anatomical group were all smaller than the corresponding values of the quasi-isometric group. Quadrant X% had a significant negative correlation with LPFA difference (R=-0.664, P<0.01). Quadrant Y% was positively correlated with LPFA difference (R=0.804, P<0.01). The difference of LPFA was significantly positively correlated with T2 values of trochlear and patellar outer cartilage (R=0.651, 0.655, P<0.01). T2 values of trochlea and lateral patella cartilage were negatively correlated with postoperative Lysholm score (R=-0.505, -0.529, P<0.01). Quadrant Y% was highly correlated with T2 value of lateral patella (R=0.825, P<0.01), and significantly correlated with T2 value of trochlear cartilage (R=0.798, P<0.01). Quadrant X% was negatively correlated with T2 values of lateral patella and pulley cartilage (R=-0.639, -0.657, P<0.01). By exploring the change of the patellofemoral joint at early stage after single-bundle anterior cruciate ligament reconstruction, we found that the quasi-anatomical reconstruction relative to the quasi-isometric reconstruction requires less patellofemoral articular cartilage degeneration and smaller patellar tilt angle. Therefore, the surgeon is required to local the center point of the femoral tunnel as far as possible at the quasi-anatomical position, thereby minimizing the degeneration of the patellofemoral joint.

Osteotomía de Fulkerson modificada por Heatley para tratamiento del dolor patelofemoral: serie de casos / Heatley modified Fulkerson osteotomy for the treatment of patellar femoral pain. A case series

Introducción El síndrome de dolor patelofemoral (SDPF) es una posible causa de dolor anterior en la rodilla que afecta predominantemente a mujeres jóvenes. No existe hasta el momento un consenso en cuanto a la etiología, pero la evidencia sugiere que el malalineamiento patelofemoral probablemente desempeña un papel en la patogénesis del dolor y particularmente en la condromalacia. Las osteotomías clásicamente utilizadas y descritas en la literatura reportan resultados funcionales variables, sin embargo los buenos resultados descritos en la literatura se encuentran en un rango entre el 50%-80%, lo que indica alguna dificultad con la reproducibilidad de la técnica o su eficacia, por lo que queremos evaluar los resultados de una técnica diferente. Materiales y Métodos Estudio de serie de casos prospectivo de pacientes con síndrome de dolor patelofemoral tratados con una nueva técnica de osteotomía de la tuberosidad tibial anterior anteromedializadora en V. Resultados Se evaluaron 19 rodillas, los promedios de intensidad de dolor fueron de 9 en el preoperatorio, 4 y 3 en el seguimiento a tres y seis meses, en la escala de Kujala se obtuvo un promedio de 33 puntos en el preoperatorio, de 75 a los 3 meses y de 87 a los seis meses. Discusión En nuestro estudio consideramos un porcentaje de 94,7% de buenos o excelentes resultados y 5% de malos resultados. La técnica descrita y utilizada en nuestro estudio presenta una tasa de buenos resultados similar a las descritas en la literatura con otras técnicas quirúrgicas y con diferentes escalas funcionales.

Background Patellofemoral pain syndrome (PFPS) is a possible cause of anterior knee pain that predominantly affects young women. To date, there is no consensus regarding the aetiology, but the evidence suggests that patellofemoral misalignment probably plays a role in the pathogenesis of pain and particularly in chondromalacia. Osteotomies classically used and described in the literature report variable functional results. As the good results described in the literature are in a range between 50%-80%, this indicates some difficulty with the reproducibility of the technique, or its effectiveness, we wish to evaluate the results of a different technique. Materials and Methods Prospective case series study of patients with patellofemoral pain syndrome treated with a new osteotomy technique of the anterior tibial tuberosity, anterior-medialized, in V. Results A total of 19 knees were evaluated. The mean pain intensity was 9 in the preoperative period, and 4 and 3 in the follow-up at three and six months, respectively. A mean of 33 points on the Kujala scale was obtained in the pre-operative period, and 75 at 3 months and 87 at six months follow-up. Discussion A percentage of 94.7% was considered good or excellent results, and 5% of considered as bad. The technique described and used in our study presents a rate of good results similar to those described in the literature with other surgical techniques and with different functional scales.

Biomechanical Study of Different Femoral Fixation Devices in the Reconstruction of the Medial Patellofemoral Ligament in Porcine Knees / Estudo biomecânico de diferentes dispositivos de fixação femoral na reconstrução do ligamento patelofemoral medial em joelhos de suínos

Abstract Objective To evaluate different femoral fixation devices for medial patellofemoral ligament reconstruction and compare their effectiveness regarding fixation strength up to failure in porcine knees. Methods Thirty porcine knees were used, divided into three groups of 10 knees. The removed grafts were dissected from the extensor tendons of porcine feet. In each group, the graft was fixed to the femur with an interference screw, an anchor, or adductor tenodesis. The three methods were subjected to biomechanical tests using a universal Tensile testing machine at a speed of 20 mm/minute. Results The highest average linear resistance under lateral traction occurred in group 1, "screw fixation" (185.45 ± 41.22 N), followed by group 2, "anchor fixation" (152.97 ± 49, 43 N); the lower average was observed in group 3, "tenodesis fixation" (76.69 ± 18.90 N). According to the fixed error margin (5%), there was a significant difference between groups (p < 0.001); in addition, multiple comparison tests (between group pairs) also showed significant differences. Variability was small, since the variance coefficient was lower than 33.3%. Conclusion Interference screws in bone tunnels and mountable anchors fixation with high resistance wire are strong enough for femoral fixation in porcine medial patellofemoral ligament reconstruction. Adductor tenodesis, however, was deemed fragile for such purpose.

Resumo Objetivo Avaliar diferentes dispositivos de fixação femoral na reconstrução do ligamento patelofemoral medial para comparar sua eficácia quanto à força de fixação até a falha em joelhos suínos. Métodos Foram ensaiados 30 joelhos de suínos subdivididos em 3 grupos de 10 joelhos. Os enxertos retirados foram dissecados de tendões extensores das patas dos suínos. Cada grupo teve o enxerto fixado ao fêmur com parafuso de interferência, âncora, ou tenodese no tendão adutor. Os 3 métodos foram submetidos à testes biomecânicos utilizando uma máquina universal de ensaio de tração com uma velocidade de 20 mm/min. Resultados Verificamos que a média mais elevada da resistência linear sob tração lateral (185,45 ± 41,22 N) ocorreu no grupo 1: "fixação por parafuso," seguido do grupo 2: "fixação por âncora" (152,97 ± 49,43 N), e a média foi menor no grupo 3: "fixação por tenodese" (76,69 ± 18,90 N). Para a margem de erro fixada (5%), comprovou-se a diferença significativa entre os grupos (p < 0,001) e também através dos testes de comparações múltiplas (entre os pares de grupos) verificou-se a ocorrência de diferenças significativas. A variabilidade expressada por meio do coeficiente de variação mostrou-se reduzida, já que a referida medida foi inferior a 33,3%. Conclusão O uso de parafusos de interferência no túnel ósseo de joelhos porcinos é suficientemente forte para fixação femoral na reconstrução do ligamento patelofemoral medial, assim como a fixação com âncoras montáveis com fio de alta resistência. Entretanto, a tenodese no tendão adutor mostrou-se frágil para essa finalidade.

Difference of Isokinetic Angle-Specific Moment Curves in Anterior Cruciate Ligament-injured Patients with or without Patellofemoral Articular Cartilage Injury / 中国康复理论与实践

Objective:To investigate the difference of isokinetic angle-specific moment curves between anterior cruciate ligament (ACL)-injured patients with and without patellofemoral cartilage injury (PFCI). Methods:A retrospective analysis was performed on patients underwent knee arthroscopy and isokinetic muscle strength testing before surgery from September, 2018 to September, 2019. Seventeen ACL-injured patients with PFCI and 17 ACL-injured patients without PFCI who matched in age, sex and meniscus injury were selected. Before arthroscopy, isometric and isokinetic strength of knee flexion and extension at velocity of 180°/s and 60°/s was tested by isokinetic dynamometer. Normalized torque-angle curves (torque/body mass) were generated in steps of 1° and the differences in angle-specific moment curves between two groups were compared. Results:At 180°/s, there was no significant difference in flexion isokinetic torque both healthy side and affected side between two groups (P >0.05); and no difference in extension torque of the healthy side (P >0.05), however, there was significant difference in extension torque of the affected side at 88° to 90° between two groups (t > 2.102, P <0.05). At 60°/s, there was significant difference in flexion torque of the healthy side at 62° to 82° between two groups (|t| >2.056, P <0.05), and no significant difference was found in flexion torque of the affected side (P >0.05), nor in extension torque of both sides between two groups (P > 0.05). A curve change was found at the beginning of the flexion and extension isokinetic moment curves at the velocity of 180°/s. The isometric knee extension torque was significantly different in the affected side between two groups (t = 2.858, P < 0.01), and no difference was found in isometric knee flexion torque in the affected side as well as both extension and flexion torques in the healthy side between two groups (t < 1.905, P > 0.05). Conclusion:The lower the isokinetic speed, the more significant the difference of strength is between ACL-injury patients with and without PFCI. High speed exercise is recommended for ACL-injured patients with PFCI.

Immediate Effect Of Kinesio Taping V/S Mcconnell Taping In Patellofemoral Oa Knee Patients

Background: Patello-femoral joint osteoarthritis is very common and occurs due to loss of cartilage of patella and trocheal groove in approximately half of the patients diagnosed with Osteoarthritis knee. Taping can be used to reduce pain in knee osteoarthritis. Different types of taping are done on Osteoarthritis Knee patients to see their individual effect, but very few studies have been done to compare the effect of 2 different types of tape. AIM: To compare the immediate effects of Kinesio taping and McConnell taping on patellofemoral joint osteoarthritis knee patients. Objectives: To compare the effects of Kinesio taping and McConnell taping on Knee flexion and extension Range of motion, pain on Numerical rating scale during Squatting and Descending stairs in patellofemoral joint osteoarthritis patients Materials and methods: This was an Experimental Pre/Post study. Primary data collection was done using random sampling. 60 Patellofemoral Joint Osteoarthritis knee patients between 45-55 age group were selected and were divided into two groups- Group A-Kinesio Taping and Group B- McConnell Taping group containing 30 each. ThePre and Post Assessment of both the groups was done using Goniometer for Knee ROM and Numerical Rating Scale(NRS) for pain score during Squatting and Descending stairs. Results: The result of this study by Mann-whitney test showed that Kinesio taping has statistical significant increase in knee range of motion (flexion and extension)( p-value=0.0334). And statistical significant decrease in pain score on NRS during Squatting (p-value=0.0212) Conclusion: Kinesio taping has shown statistical significant increase in Knee Range of Motion, and statistical significant decrease in pain on Numerical Rating Scale(NRS) during Squatting, while no significant difference on Numerical Rating Scale (NRS) during descending stairs when compared to McConnell taping.

Functional Evaluation after Medial Patellofemoral Ligament Reconstruction in Athletes / Avaliação funcional da reconstrução do ligamento patelofemoral medial em atletas

Abstract Objective The aim of the present study was to evaluate the clinical results, functional outcomes, and risk factors after anatomic reconstructions using knee flexor grafts in athletes. Methods The authors followed-up 32 patients and 34 knees for 1 year in a prospective design case series evaluating pre- and postoperative functional scores (Kujala and Lysholm) and associated risk factors. Results All of the 32 patients had a significant increase of the Lysholm and Kujala scores. Patients with < 5 preoperative dislocations had a better score on the Lysholm and Kujala scales. The mean preoperative Lysholm score was 62.8, and the mean postoperative score was 94.3. The mean preoperative Kujala score was 63.0, and the mean postoperative score was 94.0. Conclusion Medial patellofemoral ligament reconstruction with hamstring graft in athletes with patellar instability improved clinical and functional scores. The bone drilling through the patella and the positioning of the femoral tunnel should be judiciously performed.

Resumo Objetivo Avaliar os resultados clínicos e funcionais da reconstrução anatômica do ligamento patelofemoral medial com tendões flexores em atletas. Métodos Estudo tipo série de casos, prospectivo, que analisou a reconstrução do ligamento patelofemoralmedial em32 pacientes (34 joelhos). A avaliação funcional foi feita pelos escores Lysholm e Kujala nos períodos pré e pós-operatórios e os fatores de risco envolvidos foram avaliados. Resultados Dos 32 pacientes analisados, todos obtiveram melhoria dos escores funcionais comparativamente ao período pré-operatório. Pacientes com menos de cinco episódios de luxação prévios obtiveram melhores resultados funcionais. O valor médio de Lysholm no pré-operatório foi de 62,8 e no pós-operatório de 94,3, quanto ao escore de Kujala a média pré-operatório foi de 63,0 e pós-operatória de 94,0. Conclusão A reconstrução do ligamento patelofemoral medial com enxerto de tendão flexor do joelho em atletas propiciou melhoria dos escores clínicos e funcionais nos pacientes com instabilidade patelofemoral. A perfuração óssea da patela e o posicionamento do túnel femoral devem ocorrer de forma judiciosa.

Evaluation of the Reproducibility of the Dejour Classification for Femoropatellar Instability / Avaliação da reprodutibilidade da classificação de Dejour para instabilidade femoropatelar

Abstract Objective To evaluate the classification proposed by David Dejour to describe trochlear dysplasia of the knee through inter- and intraobserver reproducibility measurements. Methods Ten patients with trochlear dysplasia were studied. Three physicians, members of the Sociedade Brasileira de Cirurgia do Joelho (Brazilian Society of Knee Surgery), were invited to evaluate the images. Intra- and interobserver analyses were performed at one-week intervals. Reproducibility was evaluated in four scenarios: using only radiography; using radiography and tomography; using radiography and consulting the classification; and using radiography and tomography, consulting the classification. Results The intraobserver evaluation presented discordant results. In the interobserver analysis, the degree of agreement was low for the analyses that used only radiography and excellent for those in which both radiography and tomography were used. Conclusion The Dejour classification presented a low intra- and interobserver reproducibilitywhenonly the profile radiography was used. It was demonstrated that the use of the radiography alone for classificationmay generate lack of uniformity even among experienced observers. However, when radiography and tomography were combined, reproducibility improved.

Resumo Objetivo Avaliar, pela reprodutibilidade interobservador e intraobservador, a classificação proposta por David Dejour para descrever a displasia troclear do joelho. Métodos Foram estudados dez pacientes com diagnóstico de displasia troclear. Três médicos membros da Sociedade Brasileira de Cirurgia do Joelho foram convidados para avaliar as imagens. Análises intra- e interobservador foram feitas com intervalo de uma semana. A reprodutibilidade foi avaliada em quatro cenários: uso de radiografia; uso de radiografia e tomografia; uso de radiografia, consultando-se a classificação no momento; e uso de radiografia e tomografia, consultando-se a classificação no momento. Resultados A avaliação intraobservador apresentou resultados discordantes. Na análise interobservador, o grau de concordância foi baixo para as análises que usavam apenas a radiografia e excelente para aquelas que associavamradiografia e tomografia. Conclusão A classificação de Dejour apresentou uma baixa reprodutibilidade intra e interobservador quando usada somente a radiografia em perfil. Demonstrou-se que o uso apenas da radiografia para classificar pode gerar falta de uniformidade até mesmo entre observadores experientes. Contudo, quando radiografia e tomografia foram associadas, a reprodutibilidade melhorou.

The Influence of Curve Running on Patellofemoral Joint Stress / 医用生物力学

Objective To explore the changes in patellofemoral joint stress of lower limbs during curve running at a slower running speed, so as to analyze the possibility of increasing patellofemoral pain due to long curve running. Methods Newtest portable speed measurement system, Motion infrared high speed motion capture system, Kistler three-dimensional force plate were used to collect the kinematic parameters and ground reaction force from a total of 13 male college students without sports specialty at straight track and curve track (with inner diameter of 36 m) at the speed of (4.0±0.2) m/s. Results Compared with linear running, the patellofemoral joint stress at lateral side of the leg significantly increased during curve running. There were no significant differences in knee flexion angles and knee extensor moments when patellofemoral joint stress increased during curve running. Conclusions Long curve running is a contributing factor with respect to the development of patellofemoral pain in lateral leg and aggravating patellofemoral pain. It is suggested that running enthusiasts and patients with patellofemoral pain should avoid repeating long curve running.

Relationship between post?operative residual patellar J sign and the laxity of reconstructed medial patellofemoral liga?ment in recurrent patellar instability adult patients / 中华骨科杂志

Objective To discover the relationship between the post?operative positive residual patellar J sign and the laxity of reconstructed medial patellofemoral ligament (MPFL) after MPFL reconstruction combined with tibial tubercle osteotomy (TTO). Methods A total of 39 consecutive recurrent patellar dislocation (RPD) adult patients who were performed MPFL recon?struction and TTO with more than 2 follow?up time were analyzed retrospectively in the present study. The patellar tracking of all the patients was evaluated and was classified into positive patellar J sign group and negative J sign control group during knee ac?tive flexion and extension at final follow up. The computed tomography (CT) examination was performed in all patients at 0°exten?sion of the knee. The patellar laxity index measured by patellar glide test (PGT) and the radiographic parameters (tibial tuberosity?trochlear groove distance, bisect offset index, patella trochlear?groove distance, patella lateral tilt angle, femoral anteversion angle, tibial external angle and knee rotational angle) calculated by CT scans slices as well as the pre?/post?operative knee functional scores including International Knee Documentation Committee (IKDC) score, Kujala score, and Lysholm score were compared be?tween the positive group and negative group at final follow up. Results The average follow?up duration was 26.3±6.7 months (range 24-31) and all the patients did not suffer from the RPD during the follow?up. Ten (26%, 10/39) patients performed positive J sign, and the remaining 29 (74%, 29/39) performed negatively. The two groups were compatible with no significant difference in age, gender, injury side, follow?up duration and preoperative knee function scores (P＞0.05). At the final follow up, the patellar laxity index in the positive J sign group was 34.9%±6.9%, while that in the negative group was 24.6%±8.6%. There was signifi?cantly difference in the patellar laxity index between two groups (t=-3.413, P=0.002). The bisect offset index in the positive group was 102.9%±12.4%, while that in the negative group was 76.0%±18.4%. There was significantly difference in the bisect offset in?dex between two groups (t=-4.268, P=0.000). The patella trochlear?groove distance in the positive group was 2.2±3.7 mm, while that in the negative group was-7.6±5.8 mm. There was significantly difference in the patella trochlear?groove distance between two groups (t=-4.233, P=0.000). The two groups were compatible with no significant difference in tibial tuberosity?trochlear groove distance, patella lateral tilt angle, femoral anteversion angle, tibial external angle and knee rotational angle (P＞0.05). The IKDC, Kujala, and Lysholm in the positive group were 86.4±6.5, 85.3±1.1, 91.5±7.9 respectively with significantly differences compared with preoperative scores 53.3±2.4, 73.2±9.7, 76.7±6.6 (t=-10.163, P=0.000; t=-1.274, P=0.023; t=-8.533, P=0.018). The IKDC, Kujala, and Lysholm in the negative group were 87.3±8.6, 84.3±4.7, 93.1±4.3 respectively with significantly differences compared with preoperative scores 49.1±4.6, 71.4±6.5, 79.5±7.0 (t=-14.381, P=0.000; t=-0.068, P=0.037; t=-6.902, P=0.013). There were no significant difference in the postoperative knee function scores between the two groups (P＞0.05). Conclusion RPD patients can recover the patellar instability from the surgical technique of MPFL reconstruction and TTO and none of them suffer from the RPD during the follow?up. However, the morbidity of post?operative positive residual patellar J sign was 26%. The positive J sign might increase the laxity of patella.

Ressarch of prior-localization femoral tunnel in medial patellofemoral ligament reconstruction / 中国修复重建外科杂志

Objective: To introduce the method of prior-localization femoral tunnel by using a special positioning tool under the C-arm radiographic machine before surgery, and to study the effect on the knee function recovery after medial patellofemoral ligament (MPFL) reconstruction. Methods: Between January 2014 and January 2016, 32 patients with recurrent unilateral knee patellar dislocation were treated by arthroscopic patellofemoral lateral retinaculum release and MPFL reconstruction. The femoral tunnel position during MPFL reconstruction was prior-localizated under C-arm radiographic machine before operation. There were 8 males and 24 females, aged from 15 to 37 years, with an average of 23.8 years. The time from injury to admission ranged from 1 to 24 months, with an average of 9.7 months. Isometric point distance was measured on CT three-dimensional reconstruction image after operation to evaluate whether the position of femoral tunnel was isometric, and knee joint function was evaluated by Lysholm score. Spearman correlation analysis was performed between isometric point distance and Lysholm score. Results: All the 32 patients were followed up 12-18 months (mean, 14.2 months). No symptoms of patellar subluxation or dislocation was found during follow-up. Patellar extrapolation test and patellar extrapolation fear test were negative. The isometric point distance was 1.5-5.9 mm (mean, 3.44 mm) at 3 days after operation. All femoral tunnels were located in equidistant tunnels. At last follow-up, the Lysholm score of the patients was 92.8±2.1, which was significantly improved when compared with preoperative score (54.4±2.8) ( t=61.911, P=0.000). Isometric point distance was negatively correlated with Lysholm score ( r=-0.454, P=0.009). Conclusion: C-arm radiographic machine can locate the femoral tunnel position of MPFL easily and accurately before operation. The short-term and medium-term effectiveness are satisfactory, and the ionizing radiation injury caused by multiple fluoroscopy during operation is avoided.

Arthroscopic denervation of patella combined with microfracture for patellofemoral arthritis / 中国骨伤

OBJECTIVE@#To explore the clinical effect of knee denervation combined with micro-fracture under arthroscope in the treatment of patellofemoral arthritis.@*METHODS@#From May 2015 to May 2018, 60 patients with knee joint degenerative patellofemoral arthritis were treated, including 28 males and 32 females, aged from 24 to 56(40.5±3.35) years old. Among them, 30 cases underwent arthroscopic debridement alone(control group), 30 cases underwent arthroscopic debridement, peripatellar denervation combined with cartilage cone and patellofemoral articular surface microfracture treatment (treatment group). VAS, Lysholm and Kujala scores were used to evaluate the therapeutic effect.@*RESULTS@#No complications such as wound infection, vascular nerve injury and deep venous thrombosis occurred in all patients. The patients were followed up for 7 to 36 months with an average of 12.5 months. The VAS scores of the two groups were improved 4 weeks after operation, and the improvement of the treatment group was significantly better than that of the control group, the difference was statistically significant (<0.05). Lysholm and Kujala scores were compared at the last follow-up of the two groups, the improvement of the treatment group was significantly better than that of the control group.@*CONCLUSIONS@#The treatment of patellofemoral arthritis with patellar denervation combined with microfracture can better relieve pain and improve knee function.