Gait kinematics of osteoarthritic knees after intra-articular viscosupplementation: A double-blinded randomized controlled trial.

BACKGROUND: The utilization of subjective questionnaires for assessing conservative treatment in knee osteoarthritis may present challenges in identifying differences due to inadequate statistical power. Objective tools, such as three-dimensional (3D) kinematic analysis, are accurate and reproducible methods. However, no high-quality studies assessing the effects of intra-articular viscosupplementation (VS) have been published. Therefore, the objective of the study was to evaluate gait kinematics of patients with advanced knee osteoarthritis after VS. METHODS: Forty-two patients were randomized to receive either VS or saline injection (placebo). They underwent 3D kinematic gait analysis before and at 1, 6, and 12 weeks after treatment and knee angles during stance phase were determined. Patients and the healthcare team responsible for data collection, processing, and analysis were blinded to group allocation. Between-group comparisons were conducted using linear mixed models. RESULTS: Compared with placebo, the VS increased the maximum knee extension (3.2° (0.7-5.7)) and decreased the maximum knee flexion (-3.6° (-6.1 to -1.2)) on the sagittal plane at 1 week. At 6 weeks, the VS group sustained a reduced maximum knee flexion (-2.6° (-5.2 to 0.0)). On the axial plane, the VS group demonstrated an increase in maximum internal rotation at 12 weeks (3.9° (0.3 to 7.7)). The VS group exhibited reduced single-leg stance time at 1 week and increased total stance time at 12 weeks. CONCLUSIONS: VS led to short- and long-term kinematic improvements in the sagittal and axial planes, leading to a gait pattern closer to that observed in individuals with less severe osteoarthritic knees.

Variables Associated With Knee Valgus in Male Professional Soccer Players During a Single-Leg Vertical Landing Task.

Prior studies have explored the relationship between knee valgus and musculoskeletal variables to formulate injury prevention programs, primarily for females. Nonetheless, there is insufficient evidence pertaining to professional male soccer players. Here, the aim was to test the correlation of lateral trunk inclination, hip adduction, hip internal rotation, ankle dorsiflexion range of motion, and hip isometric strength with knee valgus during the single-leg vertical jump test. Twenty-four professional male soccer players performed a single-leg vertical hop test, hip strength assessments, and an ankle dorsiflexion range of motion test. A motion analysis system was employed for kinematic analysis. Maximal isometric hip strength and ankle dorsiflexion range of motion were tested using a handheld dynamometer and a digital inclinometer, respectively. The correlation of peak knee valgus with peak lateral trunk inclination was .43 during the landing phase (P = .04) and with peak hip internal rotation was -.68 (P < .001). For knee valgus angular displacement, only peak lateral trunk inclination presented a moderate positive correlation (r = .40, P = .05). This study showed that trunk and hip kinematics are associated with knee valgus, which could consequently lead to increased knee overload in male professional soccer players following a unilateral vertical landing test.

Changes in the methodology of medical teaching due to the COVID-19 pandemic.

OBJECTIVE: To evaluate the perceptions of students and teachers regarding remote teaching modality in comparison with the traditional face-to-face method. METHODS: In this observational, retrospective, comparative, single-center study, questionnaires containing three major assessment domains were sent to two groups: university professors and undergraduate and graduate students. The first domain collected demographic and general data on the platforms used. The second and third domains contained questions that compared the perception of the quality of information offered by the two systems. RESULTS: Between May and September 2020, 162 students and 71 teachers participated in the study. A greater proportion of students demonstrated previous contact with the online method, while professors had presented a greater number of courses. Most participants reported that their expectations regarding the remote teaching method were met (students, 80.3%; teachers, 94.4%). A significant number of students (83.3%) and teachers (88.7%) rated the classes as easier to attend and manage. Despite difficulties, such as concentration retention, most of the participants agree (at least partially) that the format should be maintained. CONCLUSION: The remote teaching methodology, although still incipient in Brazil, has become a reality in light of current health restrictions. Our study demonstrated a high level of overall satisfaction and a high sense of learning from both students and faculty. However, new challenges associated with this system have been identified, such as retention of attention and interference from the external environment. Longitudinal comparative studies that incorporate various aspects of medical education in all cycles are necessary to corroborate the findings of this study. DESIGN: Retrospective comparative study, level III evidence.

Extensor mechanism injury, infection, and an extended time between trauma and surgical approach are related to the need for total knee arthroplasty removal after traumatic dehiscence.

BACKGROUND: Surgical wound-related traumatic complications are rarely reported in the literature. Traumatic dehiscence is unpredictable because of the trauma magnitude and the potential of associated injuries. This study aims to report the clinical outcomes and complications of a case series due to traumatic dehiscence after total knee arthroplasty (TKA) and establish possible criteria for prognosis for maintaining the implant. METHODS: Patients admitted to an emergency room due to traumatic dehiscence after TKA were retrospectively evaluated. Patient data was analyzed and patients who maintained or not the arthroplasty were compared to establish prognosis factors. RESULTS: Thirty-two patients with traumatic dehiscence after TKA were evaluated. The trauma occurred on a mean of 14.3 +/- 25.0 days after the surgical procedure, and debridement in the operating room was performed on a mean of 6.2 +/- 4.9 hours after the trauma. Twenty patients maintained the arthroplasty until the end of follow-up and did not require revision. Factors related to arthroplasty removal were associated extensor mechanism injury (p = 0.026), time from trauma to surgical debridement (p = 0.035), and infection (p = 0.0001) CONCLUSION: Traumatic dehiscence after total knee arthroplasty is an event with a high rate of complications. Extensor mechanism Injury, infection, and extended time between trauma and surgical intervention were poor prognostic factors for arthroplasty maintenance.

Changes in the methodology of medical teaching due to the COVID-19 pandemic

ABSTRACT Objective To evaluate the perceptions of students and teachers regarding remote teaching modality in comparison with the traditional face-to-face method. Methods In this observational, retrospective, comparative, single-center study, questionnaires containing three major assessment domains were sent to two groups: university professors and undergraduate and graduate students. The first domain collected demographic and general data on the platforms used. The second and third domains contained questions that compared the perception of the quality of information offered by the two systems. Results Between May and September 2020, 162 students and 71 teachers participated in the study. A greater proportion of students demonstrated previous contact with the online method, while professors had presented a greater number of courses. Most participants reported that their expectations regarding the remote teaching method were met (students, 80.3%; teachers, 94.4%). A significant number of students (83.3%) and teachers (88.7%) rated the classes as easier to attend and manage. Despite difficulties, such as concentration retention, most of the participants agree (at least partially) that the format should be maintained. Conclusion The remote teaching methodology, although still incipient in Brazil, has become a reality in light of current health restrictions. Our study demonstrated a high level of overall satisfaction and a high sense of learning from both students and faculty. However, new challenges associated with this system have been identified, such as retention of attention and interference from the external environment. Longitudinal comparative studies that incorporate various aspects of medical education in all cycles are necessary to corroborate the findings of this study. Design Retrospective comparative study, level III evidence.

Three-dimensional printing models increase inter-rater agreement for classification and treatment of proximal humerus fractures.

BACKGROUND: Proximal humerus fractures (PHF) are frequent, however, several studies show low inter-rater agreement in the diagnosis and treatment of these injuries. Differences are usually related to the experience of the evaluators and/or the diagnostic methods used. This study was designed to investigate the hypothesis that shoulder surgeons and diagnostic imaging specialists using 3D printing models and shoulder CT scans in assessing proximal humerus fractures. METHODS: We obtained 75 tomographic exams of PHF to print three-dimensional models. After, two shoulder surgeons and two specialists in musculoskeletal imaging diagnostics analyzed CT scans and 3D models according to the Neer and AO/OTA group classification and suggested a treatment recommendation for each fracture based on the two diagnostic methods. RESULTS: The classification agreement for PHF using 3D printing models among the 4 specialists was moderate (global k = 0.470 and 0.544, respectively for AO/OTA and Neer classification) and higher than the CT classification agreement (global k = 0.436 and 0.464, respectively for AO/OTA and Neer). The inter-rater agreement between the two shoulder surgeons were substantial. For the AO/OTA classification, the inter-rater agreement using 3D printing models was higher (k = 0.700) than observed for CT (k = 0.631). For Neer classification,  inter-rater agreement with 3D models was similarly higher (k = 0.784) than CT images (k = 0.620). On the other hand, the inter-rater agreement between the two specialists in diagnostic imaging was moderate. In the AO/OTA classification, the agreement using CT was higher (k = 0.532) than using 3D printing models (k = 0.443), while for Neer classification, the agreement was similar for both 3D models (k = 0.478) and CT images (k = 0.421). Finally, the inter-rater agreement in the treatment of PHF by the 2 surgeons was higher for both classifications using 3D printing models (AO/OTA-k = 0.818 for 3D models and k = 0.537 for CT images). For Neer classification, we saw k = 0.727 for 3D printing models and k = 0.651 for CT images. CONCLUSION: The insights from this diagnostic pilot study imply that for shoulder surgeons, 3D printing models improved the diagnostic agreement, especially the treatment indication for PHF compared to CT for both AO/OTA and Neer classifications On the other hand, for specialists in diagnostic imaging, the use of 3D printing models was similar to CT scans for diagnostic agreement using both classifications. TRIAL REGISTRATION: Brazil Platform under no. CAAE 12273519.7.0000.5505.

Remnant preserving ACL reconstruction with a functional remnant is related to improved laxity but not to improved clinical outcomes in comparison to a nonfunctional remnant.

PURPOSE: The Anterior cruciate ligament (ACL) remnant has been pointed out as a ligamentization enhancer. Nonetheless, the remaining tissue can be functional if it still provides some stability or nonfunctional. This study intends to compare the clinical results and knee stability of functional vs. nonfunctional remnant preservation ACL reconstruction (ACLR). METHODS: One hundred and seventy-five patients with ACL injuries were included and underwent remnant preservation ACLR. They were divided into two groups accordingly to remnant tissue functionality: functional (Group F) and nonfunctional (Group NF). Primary outcome was defined as patient reported outcomes measured with Lysholm, IKDC and Tegner continuous scales and improvements. Secondary outcomes comprised of Lachman test, anterior drawer test, pivot shift test, extension and flexion deficit, graft coverage by remnant preserved tissue and failure rate (persistent instability or new ACL lesion). Menisci lesions, cartilage lesions and time to surgery were also recorded for each group. RESULTS: One hundred and forty-four patients were available at a mean of 30.2 ± 10.1 months: 69 Functional and 75 Nonfunctional. Lysholm, IKDC and Tegner functional outcomes demonstrated no difference between the groups, Functional compared to Nonfunctional: 88.4 ± 10.5 vs. 92.2 ± 4.9, n.s. and 83.2 ± 11.3 vs. 87 ± 5.3, n.s. and 6 (5-10) vs. 6 (5-9), n.s., respectively. Lysholm and IKDC functional outcomes improvements demonstrated differences between the groups: Functional compared to Nonfunctional (39.3 ± 9.4 vs. 42.3 ± 7.4, p = 0.014 and 37.7 ± 10 vs. 41.0 ± 6.6, p = 0.032); however, they were not clinically significant. Functional group showed more stability on physical examination pre- and post-operatively (p < 0.001, p < 0.001). There was no difference regarding extension deficit (n.s.); however, functional group had more flexion deficit (p = 0.02). Nonfunctional group had better graft coverage (p = 0.001). There was no difference regarding failure rate: 4% vs. 9%, (n.s.). CONCLUSION: Both remnant preservation ACLR techniques were able to achieve satisfactory functional outcomes. A functional remnant was not related to improved functional outcomes in comparison to a nonfunctional remnant; however, it was related to less laxity pre and postoperatively and inferior graft coverage. LEVEL OF EVIDENCE: II.

Portuguese Translation and Cross-Cultural Adaption of the Banff Patella Instability Instrument.

Objective To translate into Brazilian Portuguese and to cross-culturally adapt the Banff Questionnaire for Patellar Instability. Methods The translation and cross-cultural adaptation followed the linguistic validation process proposed by international guidelines, which consists of six steps: translation, synthesis, back-translation, review by an expert committee, pretest, and final report presentation to the authors of the original questionnaire. Literate patients with recurrent patellar instability, older than 12 years of age, who signed the informed consent form or had it signed by a legal guardian were included in the study. Patients with neurological or systemic comorbidities were excluded from the study. Results A total of 62 patients (18 males and 44 females) were included in the study. Discrepancies observed during the processes of translation and harmonization of the back-translations were modified with no need for reformulation. No pretest version replacements were required. Conclusion The Banff Questionnaire for Patellar Instability has been successfully translated and cross-culturally adapted into Brazilian Portuguese, so it can be used to assess patients with patellar instability who speak this language.

Portuguese Translation and Cross-Cultural Adaption of the Banff Patella Instability Instrument / Tradução e adaptação transcultural para a língua portuguesa do Questionário Banff para Instabilidade Patelar

Abstract Objective To translate into Brazilian Portuguese and to cross-culturally adapt the Banff Questionnaire for Patellar Instability. Methods The translation and cross-cultural adaptation followed the linguistic validation process proposed by international guidelines, which consists of six steps: translation, synthesis, back-translation, review by an expert committee, pretest, and final report presentation to the authors of the original questionnaire. Literate patients with recurrent patellar instability, older than 12 years of age, who signed the informed consent form or had it signed by a legal guardian were included in the study. Patients with neurological or systemic comorbidities were excluded from the study. Results A total of 62 patients (18 males and 44 females) were included in the study. Discrepancies observed during the processes of translation and harmonization of the back-translations were modified with no need for reformulation. No pretest version replacements were required. Conclusion The Banff Questionnaire for Patellar Instability has been successfully translated and cross-culturally adapted into Brazilian Portuguese, so it can be used to assess patients with patellar instability who speak this language.

Resumo Objetivo Realizar a tradução para a língua portuguesa falada no Brasil e a adaptação transcultural do questionário Banff para Instabilidade Patelar. Métodos A tradução e adaptação transcultural seguiu o processo de validação linguístico proposto por diretrizes internacionais, que consiste em seis etapas: tradução, síntese, retrotradução, revisão pelo comitê de especialistas, pré-teste, e apresentação do relatório final aos autores do questionário original. Foram incluídos no estudo pacientes alfabetizados, com diagnóstico de instabilidade patelar recorrente, com mais de 12 anos de idade, que assinaram ou tiveram o termo de consentimento livre e esclarecido assinado por um responsável legal. Foram excluídos do estudo pacientes portadores de comorbidades neurológicas ou sistêmicas. Resultados Um total de 62 pacientes (18 homens e 44 mulheres) foram incluídos no estudo. Durante os processos de tradução e harmonização das retrotraduções, foram observadas discrepâncias, que foram modificadas sem necessidade de reformulação. Não foram necessárias substituições na versão do pré-teste. Conclusão O Questionário Banff para Instabilidade Patelar foi traduzido e adaptado transculturalmente para a língua portuguesa falada no Brasil com sucesso, podendo ser utilizado para a avaliação de pacientes portadores de instabilidade patelar falantes desta língua.

Isolated MPTL reconstruction fails to restore lateral patellar stability when compared to MPFL reconstruction.

PURPOSE: To biomechanically evaluate MPTL reconstruction and compare it with two techniques for MPFL reconstruction in regard to changes in patellofemoral contact pressures and restoration of patellar stability. METHODS: This is an experimental laboratory study in eight human cadaveric knees. None had patellofemoral cartilage lesions or trochlear dysplasia as evaluated by conventional radiographs and MRI examinations. The specimens were secured in a testing apparatus, and the quadriceps was tensioned in line with the femoral shaft. Contact pressures were measured using the TekScan sensor at 30°, 60° and 90°. The sensor was placed in the patellofemoral joint through a proximal approach between femoral shaft and quadriceps tendon to not violate the medial and lateral patellofemoral complex. TekScan data were analysed to determine mean contact pressures on the medial and lateral patellar facets. Patellar lateral displacement was evaluated with the knee positioned at 30° of flexion and 9 N of quadriceps load, then a lateral force of 22 N was applied. The same protocol was used for each condition: native, medial patellofemoral complex lesion, medial patellofemoral ligament reconstruction (MPFL-R) using gracilis tendon, MPFL-R using quadriceps tendon transfer, and medial patellotibial ligament reconstruction (MPTL-R) using patellar tendon transfer. RESULTS: No statistical differences were found for mean and peak contact pressures, medial or lateral, among all three techniques. However, while both techniques of MPFL-R were able to restore the medial restraint, MPTL-R failed to restore resistance to lateral patellar translation to the native state (mean lateralization of the patella [mm]: native: 9.4; lesion: 22; gracilis MPFL-R: 8.1; quadriceps MPFL-R: 11.3; MPTL-R: 23.4 (p < 0.001). CONCLUSION: MPTL-R and both techniques for MPFL-R did not increase patellofemoral contact pressures; however, MPTL-R failed to provide a sufficient restraint against lateral patellar translation lateral translation in 30° of flexion. It, therefore, cannot be recommended as an isolated procedure for the treatment of patellar instability.

Return to Sports after ACL Reconstruction with Resection or Remnant-Preserving Technique.

Objectives To analyze the results of anterior cruciate ligament (ACL) reconstruction with remnant-preserving versus remnant-resecting technique, concerning the return to pre-lesion activity level. Methods The present retrospective cohort study has assessed adults > 18 years old who underwent ACL anatomical reconstruction between 2010 and 2014. The main outcomes assessed were: level of physical activity (4-point scale), sports participation rate, ACL rerupture defined as documented lesion requiring revision surgery and the numeric pain scale rate (NPSR). Results A total of 83 individuals were included in the study, with a mean age of 31.8 years old and follow-up mean time of 4.2 years after the surgery. A total of 34 patients underwent ACL reconstruction with remnant-preserving technique, and 49 without remnant preservation. No statistically significant difference was found between groups in all outcomes assessed: level of physical activity before the lesion and after the surgery, ACL rerupture rates and postoperative pain level. Subgroup analysis has shown a statistically significant decrease in the activity level in both groups. The most practiced sport was football; 72% of patients in the remnant group have resumed football activity versus 52.6% of the control group. Conclusion Based in these findings, the comparison between ACL reconstruction with remnant preserving technique and remnant resecting technique has shown no differences concerning the return to prelesion activity level.

Return to Sports after ACL Reconstruction with Resection or Remnant-Preserving Technique / Retorno ao esporte após reconstrução do LCA com ressecção ou preservação do remanescente

Abstract Objectives To analyze the results of anterior cruciate ligament (ACL) reconstruction with remnant-preserving versus remnant-resecting technique, concerning the return to pre-lesion activity level. Methods The present retrospective cohort study has assessed adults > 18 years old who underwent ACL anatomical reconstruction between 2010 and 2014. The main outcomes assessed were: level of physical activity (4-point scale), sports participation rate, ACL rerupture defined as documented lesion requiring revision surgery and the numeric pain scale rate (NPSR). Results A total of 83 individuals were included in the study, with a mean age of 31.8 years old and follow-up mean time of 4.2 years after the surgery. A total of 34 patients underwent ACL reconstruction with remnant-preserving technique, and 49 without remnant preservation. No statistically significant difference was found between groups in all outcomes assessed: level of physical activity before the lesion and after the surgery, ACL rerupture rates and postoperative pain level. Subgroup analysis has shown a statistically significant decrease in the activity level in both groups. The most practiced sport was football; 72% of patients in the remnant group have resumed football activity versus 52.6% of the control group. Conclusion Based in these findings, the comparison between ACL reconstruction with remnant preserving technique and remnant resecting technique has shown no differences concerning the return to prelesion activity level.

Resumo Objetivo Analisar os resultados da reconstrução do ligamento cruzado anterior (LCA) com preservação do remanescente, comparada à técnica convencional, no retorno do paciente ao nível de atividade física pré-lesão. Métodos Estudo transversal retrospectivo, que avaliou indivíduos adultos submetidos à reconstrução anatômica do LCA no período de 2010 a 2014. Os desfechos analisados foram: nível de atividade física, taxa retorno ao esporte, relesão do LCA definida como lesão documentada que necessite de nova reconstrução ligamentar, e dor pela escala numérica de dor (EVN). Resultados Foram incluídos 83 indivíduos com média de 31,8 anos de idade e seguimento médio de 4,2 anos após a cirurgia, 34 submetidos à reconstrução do LCA com preservação do remanescente, e 49 à convencional. Não houve diferença estatisticamente significativa entre os grupos na frequência de atividade física pré-lesão e pós-operatória, na taxa de relesão do LCA reconstruído e na intensidade da dor no pós-operatório. Na análise intragrupos, houve uma queda estatisticamente significativa na frequência da prática de atividade física pós-operatória para ambos os grupos em comparação ao nível pré-lesão. O tipo de esporte mais praticado foi o futebol, onde 72% pacientes do grupo remanescente retornaram ao esporte comparado a 52,6% do grupo controle; porém, essa diferença não foi estatisticamente significante. Conclusão Não foi possível observar diferenças entre os pacientes submetidos às técnicas cirúrgicas de reconstrução LCA com e sem a preservação do remanescente em relação ao retorno ao esporte, frequência de atividade física e intensidade da dor. Estudos futuros prospectivos são necessários.

Trochlear Dysplasia Does Not Affect the Outcomes of Patellofemoral Autologous Chondrocyte Implantation.

PURPOSE: To evaluate the influence of trochlear dysplasia on clinical outcomes after autologous chondrocyte implantation (ACI) for the treatment of large cartilage lesions in the patellofemoral joint (PFJ) with a minimum of 2 years' follow-up. METHODS: We performed a retrospective review of prospectively collected data of all patients submitted to cartilage repair with ACI for focal cartilage defects in the PFJ by a single surgeon. Patient factors, lesion morphology, and preoperative and postoperative patient-reported outcome measures including the Knee Injury and Osteoarthritis Score, Lysholm score, Tegner activity level, and International Knee Documentation Committee Subjective Knee Evaluation Form score were collected. Two independent observers assessed preoperative imaging to determine the presence and grade of trochlear dysplasia. Patients were stratified into 2 groups based on the presence or absence of trochlear dysplasia. Patients without trochlear dysplasia served as controls. Patients were matched 1:1 for sex, age, body mass index, lesion size, and location. RESULTS: Forty-six patients who underwent ACI in the PFJ with a mean follow-up period of 3.7 ± 1.9 years (range, 2-9 years) were enrolled in this study (23 in the trochlear dysplasia group vs 23 in the normal trochlea group). The patients' mean age was 30.1 ± 8.8 years. Patient-reported outcome measures at final follow-up did not differ between the 2 groups (P > .05). No difference in failure rates was seen between the 2 groups (n = 1 [4.3%] vs n = 1 [4.3%], P > .999). Additionally, no difference in clinical outcomes was seen between patients with high-grade dysplasia (19 patients; Dejour types B-D) and patients without dysplasia (19 patients) (P > .05). CONCLUSIONS: ACI in the PFJ provides favorable outcomes even in patients with trochlear dysplasia, which are comparable to those in patients with normal trochlear anatomy. Thus, trochlear dysplasia seems to not influence the clinical outcomes of ACI in the PFJ. LEVEL OF EVIDENCE: Level III, retrospective comparative trial.

Mechanical evaluation of tibial fixation of the hamstring tendon in anterior cruciate ligament double-bundle reconstruction with and without interference screws.

OBJECTIVE: The objective of this study was to compare two postero-lateral bundle (PLB) tibial fixation techniques for the reconstruction of the anterior cruciate ligament with double bundle: a technique without the use of an interference screw, preserving the native tibial insertion of the tendons of the gracilis and semitendineous muscles, and a technique with the use of an interference screw and without preserving the insertion of the tendons. METHODS: A comparative study was conducted in cadavers with a universal mechanical test machine. In total, 23 cadaver knees were randomized for tibial fixation of the PLB using the two techniques: Maintaining the tibial insertion of the tendons during reconstruction, without the use of an interference screw (group A, 11 cases); and fixating the graft with an interference screw, without maintaining the insertion of the tendons (group B, 12 cases). A continuous traction was performed (20 mm/min) in the same direction as the produced tunnel, and force (N), elongation (mm), rigidity (N/mm), and tension (N/mm2) were objectively determined in each group. RESULTS: Group A exhibited a maximum force (MF) of 315.4±124.7 N; maximum tension of 13.57±3.65 N/mm2; maximum elongation of 19.73±4.76 mm; force at the limit of proportionality (FLP) of 240.6±144.0 N; and an elongation at the limit of proportionality of 14.37±6.58 mm. Group B exhibited a MF of 195.7±71.8 N; maximum tension of 8.8±3.81 N/mm2; maximum elongation of 15.3±10.73 mm; FLP of 150.1±68.7 N; and an elongation at the limit of proportionality of 6.86±2.42 mm. When comparing the two groups, significant differences were observed in the variables of maximum force (p=0.016), maximum tension (p=0.019), maximum elongation (p=0.007), and elongation at the limit of proportionality (p=0.003). CONCLUSION: The use of the native insertion of the semitendineous and gracilis tendons, without an additional fixation device, presented mechanical superiority over their fixation with interference screws.

The development of the intercondylar notch in the pediatric population.

BACKGROUND: Anterior cruciate ligament (ACL) repair is increasing in frequency in younger children. Recognition of the normal development of the intercondylar notch is important for successful ACL graft placement, allowing surgeons to better understand the anatomy and risk factors related to ACL tears and its reconstruction. The purpose of this study was to compile normative data on the intercondylar notch in the pediatric population with magnetic resonance imaging (MRI), emphasizing the differences between males and females. METHODS: In this retrospective study, musculoskeletal radiologists evaluated intercondylar notch width, bicondylar distance and notch width index (NWI). A total of 253 MRI examinations (130 males and 123 females between six and 18 years of age) were included. The association between measurements, sex and age was considered. Linear and fractional polynomial regression models were used to evaluate the relationships between measurements. RESULTS: Intercondylar notch width increased up to 10 years of age in females and 11 years of age in males, with relative stabilization up to 13 years in girls and 14 years in boys and a slight reduction in values at subsequent ages. Bicondylar distance showed significant progressive growth with age in both sexes. NWI showed a discrete and homogenous reduction with age in both sexes. CONCLUSION: Intercondylar notch width interrupts its growth around 10-11 years of age, with relative stabilization up to 13-14 years and a slight reduction in dimensions in subsequent ages. This growth pattern resembles the development of the ACL area observed in recent studies.

Mechanical evaluation of tibial fixation of the hamstring tendon in anterior cruciate ligament double-bundle reconstruction with and without interference screws

OBJECTIVE: The objective of this study was to compare two postero-lateral bundle (PLB) tibial fixation techniques for the reconstruction of the anterior cruciate ligament with double bundle: a technique without the use of an interference screw, preserving the native tibial insertion of the tendons of the gracilis and semitendineous muscles, and a technique with the use of an interference screw and without preserving the insertion of the tendons. METHODS: A comparative study was conducted in cadavers with a universal mechanical test machine. In total, 23 cadaver knees were randomized for tibial fixation of the PLB using the two techniques: Maintaining the tibial insertion of the tendons during reconstruction, without the use of an interference screw (group A, 11 cases); and fixating the graft with an interference screw, without maintaining the insertion of the tendons (group B, 12 cases). A continuous traction was performed (20 mm/min) in the same direction as the produced tunnel, and force (N), elongation (mm), rigidity (N/mm), and tension (N/mm2) were objectively determined in each group. RESULTS: Group A exhibited a maximum force (MF) of 315.4±124.7 N; maximum tension of 13.57±3.65 N/mm2; maximum elongation of 19.73±4.76 mm; force at the limit of proportionality (FLP) of 240.6±144.0 N; and an elongation at the limit of proportionality of 14.37±6.58 mm. Group B exhibited a MF of 195.7±71.8 N; maximum tension of 8.8±3.81 N/mm2; maximum elongation of 15.3±10.73 mm; FLP of 150.1±68.7 N; and an elongation at the limit of proportionality of 6.86±2.42 mm. When comparing the two groups, significant differences were observed in the variables of maximum force (p=0.016), maximum tension (p=0.019), maximum elongation (p=0.007), and elongation at the limit of proportionality (p=0.003). CONCLUSION: The use of the native insertion of the semitendineous and gracilis tendons, without an additional fixation device, presented mechanical superiority over their fixation with interference screws.

A Hamstring-Based Anatomic Posterolateral Knee Reconstruction With Autografts Improves Both Radiographic Instability and Functional Outcomes.

PURPOSE: To report the subjective outcomes and objective stability in a series of chronically grade III posterolateral injured knees treated with a hamstring-based anatomic posterolateral corner (PLC) reconstruction technique using autografts. METHODS: An outcome study of patients with a chronic complete tear of all ligamentous structures of the PLC (>5 mm of varus gapping at 30o, ≥10° of external tibial rotation during the dial test, ≥4 mm of increased lateral compartment opening during varus stress radiographs) was performed. The patients were evaluated subjectively with Lysholm, International Knee Documentation Committee (IKDC), and Tegner scores and objectively with varus stress radiographs at 20° of knee flexion, IKDC objective scores, and recurvatum evaluation. Institutional review board approval: CEP/UNIFESP n: 1251/2016. RESULTS: Twenty-nine of 33 patients were available for follow up at an average of 31.9 ± 12.3 months (range, 24-59 months) postoperatively. Twenty-five patients underwent multiple-ligament reconstruction without prior osteotomy. No patient had an isolated PLC knee reconstruction. The average comparative preoperative and postoperative outcomes were, respectively: Lysholm: 49.7 ± 10.3, 81.2 ± 12.8, P < .001, 89.7% met minimal detectable change; IKDC: 36.7 ± 8.3, 70.4 ± 19.8, P < .001, 82.8% met minimal clinically important difference; Tegner, 6.6 ± 1.3, 5.5 ± 1.6, P < .001; and varus stress radiograph: 7.1 ± 3.1 mm, 1.8 ± 1.8 mm, P < .001. A significant improvement, P < .001, was found between preoperative and postoperative IKDC objective scores for varus opening at 0° and 30° and external rotation measured by the dial test at 30°. Recurvatum was also improved: preoperatively, 52% had a low-grade and 48% had a high-grade recurvatum, whereas postoperatively, 100% were classified as low grade, P < .001. CONCLUSIONS: The presented anatomic PLC reconstruction, concomitant to other surgical procedures and ligament reconstructions, is a valid technique in a multiligamentous knee injury involving the PLC, improving subjective outcomes and objective stability in patients with a chronic PLC knee injury, similar to historical controls. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Anteromedial Tibial Tubercle Osteotomy Improves Results of Medial Patellofemoral Ligament Reconstruction for Recurrent Patellar Instability in Patients With Tibial Tuberosity-Trochlear Groove Distance of 17 to 20 mm.

PURPOSE: To compare the midterm clinical outcomes of anteromedialization tibial tubercle osteotomy combined with medial patellofemoral ligament reconstruction (TTO+MPFLR) with MPFLR alone (MPFLRa) for the treatment of recurrent patellar instability (RPI) in patients with a tibial tuberosity-trochlear groove (TT-TG) of 17 to 20 mm. METHODS: From January 2008 to August 2013, patients with RPI and a TT-TG of 17 to 20 mm were divided into 2 groups: TTO+MPFLR or MPFLRa. Subjects were evaluated for J sign classification (1-4+); patellar glide (1-4+); the apprehension test; increased femoral anteversion; the Caton index; trochlear dysplasia; TT-TG; and Kujala, Lysholm, International Knee Documentation Committee (IKDC), and Tegner scores. Kujala improvement was the primary outcome. RESULTS: Forty-two subjects were evaluated, 18 in the TTO+MPFLR group and 24 in the MPFLRa group. Mean follow-up time was 40.86 months (range, 24-60 months). Demographics between the groups were not different. Preoperatively, there was no statistically significant difference between groups regarding J sign classification; patellar glide; the apprehension test; increased femoral anteversion; the Caton index; trochlear dysplasia; TT-TG; and Kujala, Lysholm, IKDC, and Tegner scores. Postoperative J sign classification mean results comparing TTO+MPFLR and MPFLRa, respectively, were 1 and 1.33 (P = .006). Improvement was significantly higher in the TTO+MPFLR group in all scores except for Tegner. Kujala improvement, 30.27 and 23.95, respectively (P = .003), was also clinically significant, favoring TTO+MPFLR. Lysholm improvement was 40.5 and 36.2, respectively (P = .02), and IKDC improvement was 38.59 and 31.6, respectively (P = .002). There were no reported recurrent subluxations or dislocations in either group. CONCLUSIONS: TTO+MPFLR resulted in better functional outcome scores and patellar kinematics compared with MPFLRa in the surgical treatment of RPI in patients with a TT-TG distance of 17 to 20 mm. LEVEL OF EVIDENCE: Level II, prospective comparative study.

Bicruciate lesion biomechanics, Part 2-treatment using a simultaneous tensioning protocol: ACL fixation first is better than PCL fixation first to restore tibiofemoral orientation.

PURPOSE: An uncommon technique for bicruciate ligament reconstruction involving simultaneous tensioning of the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) grafts with ACL graft fixation first has been pointed out as superior to the "gold-standard" PCL graft fixation first. The purpose of this study was to compare tibiofemoral biomechanics between ACL fixation first and PCL fixation first in a simultaneous tensioning protocol for bicruciate ligament reconstruction. METHODS: 12 fresh-frozen cadaveric knees (six matched pairs) were tested using a custom testing system. Neutral tibial position representing tibiofemoral orientation, anterior-posterior (AP) tibial translation, varus-valgus laxity, and internal-external rotation were measured using a Microscribe 3DLX at 0°, 30°, 60°, and 90° of knee flexion. The following knee conditions were evaluated: intact, bicruciate deficient and following bicruciate reconstruction. A simultaneous tensioning protocol was used for bicruciate reconstruction and PCL fixation first was compared to ACL fixation first. PCL graft fixation was always performed at 90° of flexion and ACL graft fixation was always performed at full extension. RESULTS: ACL fixation first achieved a tibiofemoral orientation closer to the intact knee than PCL fixation first at 90° flexion (1.8 ± 1.6 mm versus 6.1 ± 3.2 mm, p = 0.016). PCL fixation first had a larger decrease in AP translation than ACL fixation first at 30° flexion (64.6 ± 3.5% vs. 58.3 ± 2.4%, p = 0.01). No significant differences were found for varus/valgus, external-internal rotation decrements after bicruciate reconstruction nor for AP translation, varus/valgus and internal/external rotation increase after bicruciate lesion comparing ACL fixation first to PCL fixation first. CONCLUSION: Bicruciate ligament reconstruction using a simultaneous tensioning protocol with ACL fixation first resulted in a closer to normal tibiofemoral orientation. This study will help guide surgeons in decision making for the graft tensioning protocol and fixation sequence in a bicruciate ligament reconstruction. LEVEL OF EVIDENCE: V therapeutic study.

Biomechanical evaluation of tendon regeneration with adipose-derived stem cell.

The use of Adipose-Derived Stem Cells (ADSC) has been presented as a new alternative for tendon reconstruction. Have been admitted that ADSCs are related to better outcomes when used in tendon healing. This research was designed to apply the potential of ADSCs in tendon healing. Flexor digitorum superficialis tendon lesion was performed on both legs of eleven New Zealand rabbits and them, at the same time, treated as follows: Suture alone (Group III - Suture, n:10), suture associated with ADSC (Group IV - Suture + ADSC, n:10) or without suture (Group II - SHAN, n:2). At four weeks after the tendon surgery, the animal was euthanized, and the tendon evaluated (biomechanically and macroscopically). We used 5 additional New Zealand rabbits in the control group "Group I - Control, n:10". In the macroscopic evaluation, the group with ADSC presented a more homogeneous gross morphology compared with the group III. Biomechanical testing showed a lower ultimate tensile load, stiffness and a higher cross-sectional area in the group III and IV compared with the control group. The group with ADSC showed a greater ultimate tensile load, a larger cross-sectional area and bigger deformation at the ultimate tensile load when compared to the group without ADSC. In general terms, the use of ADSCs in tendon healing have biomechanical advantages compared to the non-use of ADSCs at 4 weeks after surgery. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1281-1286, 2019.