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1.
Knee Surg Sports Traumatol Arthrosc ; 30(5): 1661-1671, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34424354

RESUMEN

PURPOSE: The primary purpose of this study was to evaluate the second-look arthroscopic findings 1 year postoperatively and magnetic resonance imaging (MRI) findings 2 years after anterior cruciate ligament reconstruction (ACLR) using bone-patellar tendon-bone autograft (BTB) or hamstring tendon autograft (HT). Secondary purpose included clinical results from physical examination, including range of motion, Lachman test, pivot shift test, and knee anterior laxity evaluation, and the clinical score for subjective evaluations at 2 years after surgery. METHODS: Between 2015 and 2018, 75 patients with primary ACL injuries were divided into either the BTB group (n = 30) or HT group (n = 45). When using HT, an anatomical double-bundle ACLR was performed. BTB was indicated for athletes with sufficient motivation to return to sporting activity. Graft maturation on second-look arthroscopy was scored in terms of synovial coverage and revascularization. All participants underwent postoperative MRI evaluation 2 years postoperatively. The signal intensity (SI) characteristics of the reconstructed graft were evaluated using oblique axial proton density-weighted MR imaging (PDWI) perpendicular to the grafts. The signal/noise quotient (SNQ) was calculated to quantitatively determine the normalized SI. For clinical evaluation, the Lachman test, pivot shift test, KT-2000 evaluation, Lysholm score, and Knee injury and Osteoarthritis Outcome Score (KOOS) were used. RESULTS: Arthroscopic findings showed that the graft maturation score in the BTB group (3.6 ± 0.7) was significantly greater than that in the anteromedial bundle (AMB; 2.9 ± 0.2, p = 0.02) and posterolateral bundle (PLB; 2.0 ± 0.9, p = 0.001) in the HT group. The mean MRI-SNQs were as follows: BTB, 2.3 ± 0.5; AMB, 2.9 ± 0.9; and PLB, 4.1 ± 1.1. There were significant differences between BTB, AMB, and PLB (BTB and AMB: p = 0.04, BTB and PLB: p = 0.003, AMB and PLB: p = 0.03). Second-look arthroscopic maturation score and MRI-SNQ value significantly correlated for BTB, AMB, and PLB. No significant differences were detected in clinical scores. There was a significant difference (p = 0.02) in the knee laxity evaluation (BTB: 0.9 ± 1.1 mm; HT: 2.0 ± 1.9 mm). CONCLUSION: BTB maturation is superior to that of double-bundle HT based on morphological and MRI evaluations following anatomical ACLR, although no significant differences were found in clinical scores. Regarding clinical relevance, the advantages of BTB may help clinicians decide on using the autograft option for athletes with higher motivation to return to sporting activity because significant differences were observed in morphological evaluation, MRI assessment, and knee anterior laxity evaluation between BTB and double-bundle HT. LEVEL OF EVIDENCE: Level IV.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Tendones Isquiotibiales , Ligamento Rotuliano , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , Autoinjertos/cirugía , Tendones Isquiotibiales/trasplante , Humanos , Ligamento Rotuliano/cirugía , Trasplante Autólogo
2.
Arch Orthop Trauma Surg ; 141(11): 1927-1934, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33609182

RESUMEN

INTRODUCTION: The optimal pain management strategy for postoperative pain after anterior cruciate ligament reconstruction (ACLR) remains unclear. This study compared femoral nerve block (FNB) and adductor canal block (ACB) for pain management of early postoperative pain, knee function, and recovery of activity of daily living (ADL) after ACLR using hamstring autografts. MATERIAL AND METHODS: In this prospective, single-blind, randomised controlled trial, 64 patients aged 12-56 years who underwent anatomical double-bundle ACLR with a hamstring autograft between August 2019 and May 2020 were randomised to undergo preoperative FNB (n = 32) or ACB (n = 32). The peripheral nerve block was performed by a single experienced anaesthesiologist under ultrasound guidance. The primary outcomes were postoperative pain as evaluated using the visual analogue scale (VAS) at 3, 6, 12, 24, and 48 h postoperatively and the need for pain relief. The secondary outcome was knee function, including the recovery of range of motion, contraction of the vastus medialis, and stable walking with a double-crutch (ADL), as evaluated by blinded physical therapists. RESULTS: There were no significant differences in patient demographics between the two groups. The VAS scores, need for pain relief, knee function, and ADL did not significantly differ between the groups. CONCLUSION: FNB and ACB provided comparable outcomes related to early postoperative pain, knee function, and ADL after double-bundle ACLR using hamstring autografts. Further research is necessary to evaluate the mid- to long-term effect of each block on recovery of knee function and ADL. LEVEL OF EVIDENCE: I.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Bloqueo Nervioso , Lesiones del Ligamento Cruzado Anterior/cirugía , Autoinjertos , Nervio Femoral , Humanos , Dolor Postoperatorio/etiología , Dolor Postoperatorio/prevención & control , Estudios Prospectivos , Método Simple Ciego
3.
Knee Surg Sports Traumatol Arthrosc ; 29(11): 3839-3845, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33475806

RESUMEN

PURPOSE: This study aimed to assess the risk factors for prolonged joint effusion in patients undergoing double-bundle anterior cruciate ligament reconstruction (ACLR). METHODS: In total, 160 patients who underwent primary ACLR using autograft hamstring between 2015 and 2018 were retrospectively reviewed. Joint effusion was defined as any grade ≥ 2 (range, 0-3) according to the MRI Osteoarthritis Knee Score (MOAKS). Univariate and multivariate logistic regression analyses were performed. RESULTS: The median age of the patients was 25 years (range 14-68 years) at the time of the surgery; there were 89 women and 71 men. At 1 year, 46 (28.8%) patients experienced knee joint effusion, as defined by the MOAKS. Univariate analysis revealed that age, preoperative Kellgren-Lawrence (K-L) grade, and joint effusion at 6 months were significantly associated with joint effusion at 1 year. In the multivariate analysis, joint effusion at 6 months was significantly associated with joint effusion at 1 year (odds ratio, 68.0; 95% confidence interval, 22.1-209.4). No significant difference in the Lysholm scores was observed between patients with and without joint effusion at 1 year (n.s.). CONCLUSIONS: Joint effusion at 6 months was significantly associated with joint effusion 1 year after ACLR. LEVEL OF EVIDENCE: III.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Adolescente , Adulto , Anciano , Lesiones del Ligamento Cruzado Anterior/complicaciones , Lesiones del Ligamento Cruzado Anterior/cirugía , Femenino , Humanos , Lactante , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Estudios Retrospectivos , Trasplante Autólogo , Adulto Joven
4.
Orthop J Sports Med ; 8(11): 2325967120963050, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33457431

RESUMEN

BACKGROUND: Little is known regarding the optimal treatment for displaced, purely chondral fragments in the knee. PURPOSE: To report the clinical and radiographic outcomes of chondral fragment fixation in adolescents through use of autologous bone pegs. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This retrospective, single-center study evaluated 6 patients (mean age, 12.9 years) who underwent fixation of chondral fragments (no visualized bone attached) using autologous bone pegs (mean postoperative follow-up, 5.2 years; range, 1.4-10.9 years). The causes were trauma (n = 5) and osteochondritis dissecans (n = 1). Lesions were located in the trochlear groove (lateral, n = 3; medial, n = 2) or posterior part of the lateral femoral condyle (n = 1). The mean lesion size was 3.8 cm2 (range, 0.8-9.0 cm2). Patients were evaluated via physical examination and magnetic resonance imaging (MRI) using magnetic resonance observation of cartilage repair tissue scores. RESULTS: In total, 5 patients successfully returned to sports without restrictions at a mean of 7 months (range, 6-8 months) postoperatively. At the latest follow-up, these 5 patients had full range of motion and no joint effusion. The mean magnetic resonance observation of cartilage repair tissue score was 85 (range, 70-95) at a mean duration of 3 years (range, 1-5 years). One patient experienced failure at 1.3 years postoperatively after a traumatic injury and subsequently underwent removal of the fixed fragment and a drilling procedure. CONCLUSION: In most adolescents, fixation of chondral fragments with no visualized bony portion using autologous bone pegs provided a satisfactory success rate and good healing of cartilage tissue confirmed on MRI scans.

5.
Knee Surg Sports Traumatol Arthrosc ; 27(2): 491-497, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30196436

RESUMEN

PURPOSE: The purpose of this study was to evaluate the signal/noise quotient (SNQ) for graft maturation and the serial changes observed in the magnetic resonance imaging (MRI) findings after double-bundle (DB) anterior cruciate ligament (ACL) reconstruction using a hamstring tendon autograft at a minimum of 5 years after surgery. METHODS: Forty-five patients who underwent DB ACL reconstruction between 2007 and 2010 were included in this prospective study. All participants underwent postoperative MRI at 3 weeks and 3, 6, 9 and 12, 18, 24, 36, 48 and 50 months. The signal intensity (SI) characteristics of the reconstructed graft were evaluated on oblique axial proton density-weighted MR imaging (PDWI) perpendicular to the grafts. The signal/noise quotient (SNQ) was calculated to quantitatively determine the normalized SI. The SNQ of the AMB and PLB was evaluated separately. RESULTS: The mean SNQ of the AM bundle (AMB) continued to increase until 6 months after surgery (5.2 ± 1.2), and then gradually decreased and became well stabilized by 18 months (3.3 ± 0.5), after which it remained unchanged. On the other hand, the mean SNQ of the PL bundle (PLB) continued to increase until 9 months after surgery (6.2 ± 1.1), and then decreased incrementally and became well stabilized by 24 months (4.1 ± 0.5). The SI of PLB was significantly higher than that of AMB between 3 and 24 months (p = 0.04, 0.03, 0.01, 0.04, 0.02 and 0.03, respectively). CONCLUSIONS: These results indicate that at least 18 months is needed after ACL reconstruction to sufficiently restore the SI of the AMB, while at least 24 months are needed to for the PLB. The SI of the PLB was significantly higher than that of the AMB at 3-24 months after surgery, indicating that the PLB showed inferior graft maturity to the AMB until 24 months after surgery. For clinical relevance, the correct understanding of serial changes in graft maturation may potentially be used in decision-making regarding a return to sports. LEVEL OF EVIDENCE: Prospective case series, Level IV.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior/rehabilitación , Tendones Isquiotibiales/trasplante , Articulación de la Rodilla/diagnóstico por imagen , Trasplantes/diagnóstico por imagen , Adolescente , Adulto , Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , Autoinjertos , Femenino , Humanos , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Imagen por Resonancia Magnética , Masculino , Periodo Posoperatorio , Estudios Prospectivos , Trasplante Autólogo , Trasplantes/fisiopatología , Adulto Joven
6.
Knee Surg Sports Traumatol Arthrosc ; 26(10): 2960-2965, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29450567

RESUMEN

PURPOSE: Studies have found anatomic variation in the coronal position of the insertion site of anteromedial (AM) bundle of the anterior cruciate ligament (ACL) on the tibia, which can lead to questions about tunnel placement during ACL reconstruction. The purpose of this study was to determine how mediolateral placement of the tibial AM graft tunnel in double-bundle ACL reconstructions affects knee biomechanics. METHODS: Two different types of double-bundle ACL reconstructions were performed. The AM tibial tunnel was placed at either the medial or lateral portion of tibial AM footprint. Nine cadaveric knees were tested with the robotic/universal force-moment sensor system with the use of (1) an 89.0-N anterior tibial load at full extension (FE), 30°, 60° and 90° of knee flexion and (2) a combined 7.0-Nm valgus torque and 5.0-Nm internal tibial rotation torque at FE, 15°, 30°and 45° of knee flexion. RESULTS: Both medial (2.6 ± 1.2 mm) and lateral (1.6 ± 0.9 mm) double-bundle reconstructions reduced the anterior tibial translation (ATT) to less than the intact value (3.9 ± 0.7 mm) at FE. At all other flexion angles, there was no significant different in ATT between the intact knee and the reconstructions. At FE, the ATT for the medial AM reconstruction was different from that of the lateral AM construction and closer to the intact ACL value. CONCLUSION: The coronal tibial placement of the AM tunnel had only a slight effect on knee biomechanics. In patients with differing AM bundle coronal positions, the AM tibial tunnel can be placed anatomically at the native insertion site.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior/métodos , Articulación de la Rodilla/fisiología , Articulación de la Rodilla/cirugía , Anciano , Fenómenos Biomecánicos/fisiología , Cadáver , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Persona de Mediana Edad , Rango del Movimiento Articular/fisiología , Rotación , Torque
7.
Arthroscopy ; 32(11): 2322-2328, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27189870

RESUMEN

PURPOSE: To evaluate the effect of knee flexion angle for hamstring graft fixation, full extension (FE), or 30°, on acceleration of the knee motion during pivot-shift testing after either anatomic or nonanatomic anterior cruciate ligament (ACL) reconstruction using triaxial accelerometry. METHODS: Two types of ACL reconstructions (anatomic and nonanatomic) using 2 different angles of knee flexion during graft fixation (FE and 30°) were performed on 12 fresh-frozen human knees making 4 groups: anatomic-FE, anatomic-30°, nonanatomic-FE, and nonanatomic-30°. Manual pivot-shift testing was performed at ACL-intact, ACL-deficient, and ACL-reconstructed conditions. Three-dimensional acceleration of knee motion was recorded using a triaxial accelerometer. RESULTS: The anatomic-30° group showed the smallest overall magnitude of acceleration among the ACL-reconstructed groups (P = .0039). There were no significant differences among the anatomic-FE group, the nonanatomic-FE group, and the nonantomic-30° group (anatomic-FE vs nonanatomic-FE, P = .1093; anatomic-FE vs nonanatomic-30°, P = .8728; and nonanatomic-FE vs nonanatomic-30°, P = .1093). After ACL transection, acceleration was reduced by ACL reconstruction with the exception of the nonanatomic-FE group that did not show a significant difference when compared with the ACL-deficient (P = .4537). CONCLUSIONS: The anatomic ACL reconstruction with the graft fixed at 30° of knee flexion better restored rotational knee stability compared with FE. An ACL graft fixed with the knee at FE in anatomic position did not show a significant difference compared with the nonanatomic ACL reconstructions. CLINICAL RELEVANCE: Knee flexion angle at the time of graft fixation for ACL reconstruction can be considered to maximize the rotational knee stability.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , Inestabilidad de la Articulación/prevención & control , Inestabilidad de la Articulación/cirugía , Articulación de la Rodilla/fisiología , Articulación de la Rodilla/cirugía , Anciano , Reconstrucción del Ligamento Cruzado Anterior/efectos adversos , Artroscopía/efectos adversos , Artroscopía/métodos , Fenómenos Biomecánicos , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Movimiento , Complicaciones Posoperatorias/prevención & control , Rotación , Tendones/trasplante , Trasplante Homólogo
8.
J Bone Joint Surg Am ; 97(21): 1767-73, 2015 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-26537164

RESUMEN

BACKGROUND: The purpose of our study was to evaluate the relationship between graft placement and in situ graft force after anterior cruciate ligament (ACL) reconstruction. METHODS: Magnetic resonance imaging (MRI) was obtained for twelve human cadaveric knees. The knees, in intact and deficient-ACL states, were subjected to external loading conditions as follows: an anterior tibial load of 89 N at 0°, 15°, 30°, 45°, 60°, and 90° of flexion and a combined rotatory (simulated pivot-shift) load of 5 Nm of internal tibial torque and 7 Nm of valgus torque at 0°, 15°, and 30° of flexion. Three ACL reconstructions were performed in a randomized order: from the center of the tibial insertion site to the center of the femoral insertion site (Mid), the center of the tibial insertion site to a more vertical femoral position (S1), and the center of the tibial insertion site to an even more vertical femoral position (S2). The reconstructions were tested following the same protocol used for the intact state, and graft in situ force was calculated for the two loadings at each flexion angle. MRI was used to measure the graft inclination angle after each ACL reconstruction. RESULTS: The mean inclination angle (and standard deviation) was 51.7° ± 5.0° for the native ACL, 51.6° ± 4.1° for the Mid reconstruction (p = 0.85), 58.7° ± 5.4° for S1 (p < 0.001), and 64.7° ± 6.5° for S2 (p < 0.001). At 0°, 15°, and 30° of knee flexion, the Mid reconstruction showed in situ graft force that was closer to that of the native ACL during both anterior tibial loading and simulated pivot-shift loading than was the case for S1 and S2 reconstructions. At greater flexion angles, S1 and S2 had in situ graft force that was closer to that of the native ACL than was the case for the Mid reconstruction. CONCLUSIONS: Anatomic ACL reconstruction exposes grafts to higher loads at lower angles of knee flexion. CLINICAL RELEVANCE: Rehabilitation and return to sports progression may need to be modified to protect an anatomically placed graft after ACL reconstruction.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior/métodos , Ligamento Cruzado Anterior/trasplante , Artroscopía , Inestabilidad de la Articulación/prevención & control , Articulación de la Rodilla/fisiología , Técnicas de Sutura , Cadáver , Humanos , Rango del Movimiento Articular , Soporte de Peso/fisiología
9.
Knee Surg Sports Traumatol Arthrosc ; 23(3): 687-95, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25448139

RESUMEN

PURPOSE: Quadriceps tendon grafts have renewed interest for ACL reconstruction; however, biomechanical studies comparing anatomic single-bundle (SB) and double-bundle (DB) reconstruction techniques are rare. The purpose of this study was to compare the knee biomechanics in four different types of anatomic ACL reconstruction techniques, using the quadriceps tendon in a human cadaver. METHODS: Four different tibial (T) and femoral (F) tunnel configurations, (a) DB-2F-2T, (b) DB-2F-1T, (c) SB-1F-1T and (d) DB-1F-2T, were used for ACL reconstruction using the split quadriceps tendon with patella bone. Ten cadaver knees were subjected to an 89 N anterior tibial load and combined 7 N m valgus and 5 N m internal torques. The anterior tibial translation (ATT) and in situ force were measured using a robotic system for the ACL-intact, ACL-deficient and ACL-reconstructed knees. RESULTS: DB reconstructions mostly restored ATT to the intact ACL. The in situ forces under the anterior load in the DB reconstructions were similar to the intact ACL, but that of the SB reconstruction was different at 30°, 60° and 90° of flexion (P < 0.05). Under combined torques, the in situ force of the SB graft was less than that of intact ACL at 0°, 15° and 30° of knee flexion (P < 0.05), while that of the ACL DB reconstruction was similar to the intact ACL. CONCLUSION: DB ACL reconstruction using quadriceps tendon can restore biomechanics of the knee to that of the intact ACL regardless of whether three or four tunnels are used, but SB reconstruction does not.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior/métodos , Ligamento Cruzado Anterior/cirugía , Articulación de la Rodilla/fisiología , Tendones/trasplante , Anciano , Fenómenos Biomecánicos , Trasplante Óseo , Fémur/fisiología , Fémur/cirugía , Humanos , Articulación de la Rodilla/cirugía , Masculino , Persona de Mediana Edad , Rótula/trasplante , Rango del Movimiento Articular , Robótica , Tendones/fisiología , Tibia/fisiología , Tibia/cirugía , Torque , Soporte de Peso
10.
Knee Surg Sports Traumatol Arthrosc ; 22(5): 972-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23568389

RESUMEN

PURPOSE: Recently, single-bundle (SB) anterior cruciate ligament (ACL) reconstruction has been advanced by the anatomic concept, but the biomechanical outcome of the anatomic method has not been fully investigated, especially for rotational instability. Anatomic SB and the single over-the-top procedures are the treatment of choice for primary cases and revision or skeletally immature cases, respectively. The purpose of this study was to investigate the dynamic rotational instability of anatomic SB and over-the-top reconstruction during a pivot shift test using triaxial accelerometry. METHODS: Eight fresh frozen human cadaveric knees were used in this study. Rotational instability measurement was conducted during a pivot shift test by the use of a triaxial accelerometer attached to the tibia. The tests were performed in the ACL-intact, ACL-deficient and ACL-reconstructed knees with two different procedures (anatomic SB and over-the-top). The acceleration in three directions and the magnitude of acceleration were measured to evaluate rotational instability and compare between four different knee states. RESULTS: The overall magnitude of acceleration was significantly different (P < 0.01) between the ACL-intact knees and the ACL-deficient knees. Both anatomic SB and over-the-top ACL reconstruction significantly reduced the overall magnitude of acceleration compared to the ACL-deficient knees, but still had larger accelerations compared to the ACL-intact knees. There was no significant difference for the overall magnitude of acceleration between anatomic SB and over-the-top reconstruction procedure. CONCLUSION: Over-the-top reconstruction provides comparable result to anatomic SB reconstruction in terms of controlling the dynamic rotational stability. Over-the-top reconstruction might be one of the options for revision cases and in skeletally immature patients.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior/métodos , Ligamento Cruzado Anterior/cirugía , Inestabilidad de la Articulación/fisiopatología , Articulación de la Rodilla/cirugía , Acelerometría , Fenómenos Biomecánicos , Cadáver , Humanos , Inestabilidad de la Articulación/cirugía , Rotación
11.
Knee Surg Sports Traumatol Arthrosc ; 21(3): 589-95, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22437660

RESUMEN

PURPOSE: Conventional transtibial technique fails to restore the rotational knee stability in spite of successful anterior laxity, while anatomic anterior cruciate ligament reconstruction using the anteromedial portal technique has been developed expecting better rotational kinematics because of closer reproduction of the native anterior cruciate ligament anatomy. However, the rotational instability after those two procedures has not been fully examined especially in terms of dynamic component of the rotational stability. The purpose was to assess the effect of anatomic versus non-anatomic tunnel placement on rotational knee stability after anterior cruciate ligament reconstruction using triaxial accelerometry. METHODS: Sixteen porcine knees underwent a manual pivot-shift test at four different conditions: (1) anterior cruciate ligament intact, (2) anterior cruciate ligament deficient, (3) non-anatomic transtibial reconstruction, and (4) anatomic anteromedial portal reconstruction. The three-dimensional acceleration of knee motion during the pivot-shift test was recorded using a triaxial accelerometer. RESULTS: Both anterior cruciate ligament reconstructions decreased significantly the acceleration of the pivot-shift test from the increased level in the anterior cruciate ligament-deficient condition. However, the transtibial technique fails to reach the intact level of acceleration, while the anteromedial portal technique reduced the acceleration to even less than the intact level. CONCLUSION: The transtibial anterior cruciate ligament reconstruction could not restore the dynamic rotational stability of the intact knee, whereas the anteromedial portal technique restored the dynamic rotational stability closer to the intact level. LEVEL OF EVIDENCE: III.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior/métodos , Fémur/cirugía , Inestabilidad de la Articulación/fisiopatología , Tibia/cirugía , Acelerometría , Animales , Ligamento Cruzado Anterior/fisiopatología , Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior , Fenómenos Biomecánicos , Inestabilidad de la Articulación/cirugía , Rotación , Porcinos
12.
Knee Surg Sports Traumatol Arthrosc ; 19(8): 1233-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21350960

RESUMEN

PURPOSE: To measure the acceleration in multiple directions of the rotational instability in ACL deficient models using porcine knees. METHODS: Ten porcine knees were tested with ACL intact and tear models. The pivot shift test was performed manually, and the acceleration of the pivot shift phenomenon was recorded by the use of a triaxial accelerometer. Tests were repeated in four different ACL states: (1) intact; (2) partial AM deficient; (3) complete AM deficient, and (4) complete ACL (AM and PL) deficient. The acceleration in three directions and the magnitude of acceleration were measured to evaluate rotational instability and compare between different ACL conditions. RESULTS: Significantly increased accelerations were observed in the complete deficient ACL model, while the partial ACL tear models demonstrated a slight increase without statistical significance. The accelerometer detected stepwise increases in the acceleration with the extent of ACL tear. Additionally, the PL bundle exhibited the largest contribution for rotational instability (80.4%) when compared with the AM (19.5%) bundles. CONCLUSION: Triaxial accelerometer could serve as a quantitative evaluation of rotational instability. The present study demonstrated that PL bundle has the most important contribution for rotational instability (80.4%) when compared to IM bundle (0.01%) and AM bundle (19.5%) in porcine knee model.


Asunto(s)
Aceleración , Ligamento Cruzado Anterior/fisiopatología , Inestabilidad de la Articulación/diagnóstico , Animales , Fenómenos Biomecánicos , Articulación de la Rodilla , Modelos Animales , Rango del Movimiento Articular/fisiología , Estadísticas no Paramétricas , Sus scrofa , Porcinos
13.
Knee Surg Sports Traumatol Arthrosc ; 19(5): 728-35, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21153539

RESUMEN

PURPOSE: Different tunnel configurations have been used for double-bundle (DB) anterior cruciate ligament (ACL) reconstruction. However, controversy still exists as to whether three-tunnel DB with double-femoral tunnels and single-tibial tunnel (2F-1T) or with single-femoral tunnel and double-tibial tunnels (1F-2T) better restores intact knee biomechanics than single-bundle (SB) ACL reconstruction. The purpose was to compare the knee kinematics and in situ force in the grafts among SB and two types of three-tunnel DB ACL reconstructions performed in an anatomic fashion. METHODS: Twenty-four porcine knees were subjected to an 89-N anterior tibial load (simulated KT-1000 test) at 30°, 60°, and 90° of flexion and to a 4-Nm internal tibial torque and 7-Nm valgus torque (simulated pivot-shift test) at 30° and 60° of flexion. The resulting knee kinematics and in situ force in the ACL or replacement grafts were measured using a robotic system for (1) ACL-intact, (2) ACL-deficient, and (3) three ACL reconstructed knees: SB; DB 2F-1T; and DB 1F-2T. RESULTS: During the simulated pivot-shift test, the DB grafts more closely restored the in situ force in the intact ACL at low flexion angle than the SB graft. There were no significant differences in knee kinematics between SB and DB ACL reconstruction. The DB 2F-1T reconstruction did not show a significant difference in knee kinematics or in situ force when compared to the DB 1F-2T technique. CONCLUSION: The in situ force in the ACL is better restored with an anatomic three-tunnel DB reconstruction in response to the simulated pivot-shift test at low flexion angle when compared to an anatomic SB reconstruction. Both three-tunnel DB ACL reconstructions performed in an anatomic fashion had similar biomechanical behavior. As long as it is performed anatomically, DB ACL reconstruction could be better alternative than SB ACL reconstruction, no matter which three-tunnel procedure, 2F-1T or 1F-2T, is used.


Asunto(s)
Ligamento Cruzado Anterior/fisiopatología , Ligamento Cruzado Anterior/cirugía , Fenómenos Biomecánicos , Procedimientos de Cirugía Plástica/métodos , Animales , Artroscopía/métodos , Diseño de Equipo , Modelos Animales , Robótica/instrumentación , Estadísticas no Paramétricas , Estrés Mecánico , Porcinos , Torque
14.
Arthroscopy ; 27(3): 391-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21126846

RESUMEN

PURPOSE: The purpose of this study was to evaluate intraobserver and interobserver reliability of anterior cruciate ligament tunnel location measurement by use of 3-dimensional reconstructed computed tomography (CT). METHODS: Three-dimensional reconstructed CT images of 31 cadaveric knees were used in this study. Twenty-one knees were operated on with a double-bundle technique, and ten knees were operated on with a single-bundle technique. Femoral tunnel location was measured with 3 methods on the medial-lateral view of the lateral femoral condyle in the strictly lateral position. Tibial tunnel location was measured in the top view of the proximal tibia. The images were evaluated independently by 2 orthopaedic surgeons. A second measurement was performed, by both testers, after a 4-week interval. RESULTS: The 3 methods of femoral tunnel location measurement had intraobserver intraclass correlation coefficients (ICCs) that ranged from 0.963 to 0.998 and interobserver ICCs that ranged from 0.993 to 0.999. Tibial tunnel measurement had intraobserver ICCs that varied between 0.957 and 0.998 and interobserver ICCs that varied between 0.993 and 0.996. CONCLUSIONS: The measurement of the anterior cruciate ligament tunnel location on 3-dimensional reconstructed CT provided excellent intraobserver and interobserver reliability. CLINICAL RELEVANCE: Three-dimensional reconstructed CT can be used for further studies to assess the effect of tunnel position on knee stability and patient outcomes.


Asunto(s)
Ligamento Cruzado Anterior/diagnóstico por imagen , Ligamento Cruzado Anterior/cirugía , Imagenología Tridimensional , Tomografía Computarizada por Rayos X , Anciano , Fenómenos Biomecánicos , Cadáver , Femenino , Fémur/diagnóstico por imagen , Fémur/cirugía , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Programas Informáticos , Tibia/diagnóstico por imagen , Tibia/cirugía
15.
Forensic Sci Int ; 191(1-3): e5-10, 2009 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-19656645

RESUMEN

A mid-forties woman purchased seven different dietary supplements from Thailand on the internet and subsequently died after taking these supplements. Since there were no ingredient labels on the supplements, we identified the active ingredients using direct analysis in real time-mass spectrometry (DART-MS), direct exposure probe-MS (DEP-MS), and liquid chromatography-MS (LC-MS). DART-MS gives exact molecular weights and DEP-MS shows the fragmentation of a molecule by electron ionization. Analyses using these two instruments are rapid and do not require extraction of the sample. The compounds predicted by DART-MS and DEP-MS were confirmed by LC-MS and the active ingredients of the seven dietary supplements were identified.

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