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Purpose: This study aimed to investigate the intraoperative knee kinematics of cruciate-retaining total knee arthroplasty with a medial stabilising technique (MST-TKA) and compare the kinematics between mobile- and fixed-bearing MST-TKAs. We hypothesised that mobile-bearing MST-TKA would result in greater physiological kinematic motion than fixed-bearing MST-TKA. Methods: Twenty-one and 20 knees underwent mobile- and fixed-bearing MST-TKAs using a navigation system (Orthopilot® ver. 6.0; B. Braun Aesculap), respectively. In the preoperative and postoperative kinematic analysis, the knee was moved manually from 0° to 120°, and femoral anteroposterior translations of the medial femoral condyle (MFC) and lateral femoral condyle (LFC) were recorded every 0.1 s from 0° to 120°. Data were subsequently extracted from the software every 10° of flexion and compared between the two groups, and the correlation coefficients between preoperative and postoperative kinematics were calculated. Results: In the postoperative analysis, the MFC in the mobile-bearing group showed significant posterior translation at 100°, 110° and 120° compared to the fixed-bearing group (p < 0.01). Similarly, the LFC in the mobile-bearing group showed significant posterior translation at 100°, 110° and 120° compared to the fixed-bearing group (p < 0.05, p < 0.01 and p < 0.05, respectively). In the mobile-bearing group, the preoperative and postoperative anteroposterior translations of the MFC and LFC were correlated (p < 0.01), while in the fixed-bearing group, there was no correlation. Conclusion: The femoral rollback motion in the mobile-bearing MST-TKA correlated with the preoperative kinematics and was larger than that in the fixed-bearing group. Level of Evidence: Level II, therapeutic prospective cohort study.
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STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To develop a grading method for cervical paraspinal soft tissue damage after cervical spinal cord injury (CSCI) without major fracture based on the short T1 inversion recovery (STIR) mid-sagittal magnetic resonance image (MRI) for prediction of neurological improvements. METHODS: This study included 34 patients with CSCI without major fracture, treated conservatively for at least 1 year and graded using the STIR-MRI Grade. This system consists of anterior grades; A0: no high-intensity area (HIA), A1: linear HIA, and A2: fusiform HIA, and posterior grades; P0: no HIA, P1: HIA not exceeding the nuchal ligament, and P2: HIA exceeding the nuchal ligament, within 24 hours postinjury. The American Spinal Injury Association impairment scale (AIS) and the Japanese Orthopedic Association (JOA) scores were examined. RESULTS: Anterior grades were not significantly correlated with the AIS and JOA score. At both injury and final follow-up, the AIS in P2 patients was significantly more severe (P = 0.007, P = 0.015, respectively) than that in P0 patients. At the injury, the AIS in P2 patients was significantly more severe (P = 0.008) than that in P1 patients. Among P2 patients only, the JOA score at the injury (1.4 points) did not improve by the final follow-up (3.9 points). The final follow-up JOA score (3.9 points) in P2 patients was significantly lower than that (13.6 points) in P0 patients (P = 0.016). CONCLUSIONS: Grade P2 led to poor neurological outcomes. The STIR-MRI Grade is a prognostic indicator for neurological improvements past-CSCI.
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PURPOSE: This study aimed to investigate the rate at which patients returned to sports after open wedge high tibial osteotomy and identify the continuity of sports activity post-operatively. METHODS: Thirty-five patients (40 knees) who underwent open-wedge high tibial osteotomy (OW-HTO) in medial knee osteoarthritis were included in this study. The mean age of the patients who underwent surgery was 55.1 ± 10.7 years, and the mean follow-up period was 41.0 ± 24.7 months. Clinical results and radiographic parameters calculated in standing whole-leg radiographs preoperatively, post-operatively, and at the final follow-up were evaluated. RESULTS: Thirty-one patients (88.6%) were able to return to preoperative sports activity; however, only 14 patients (40.0%) completely returned to preoperative sports activity levels. Of the 31 patients who returned to sports activity, 10 patients (32.3%) maintained post-operative sporting activity levels at the final follow-up. In radiographic parameters, the weight-bearing line ratio was considered loss of correction in the post-operative period leading to the final follow-up. Patients who completely returned to sports and maintained sporting activity levels at the final follow-up had significantly higher the Knee Injury and Osteoarthritis Outcome Score pain subscale values and lower visual analogue scale of knee pain at pre-surgery and final follow-up than other patients, including those who partially returned to sports. CONCLUSIONS: The proportion of patients who returned to sports after OW-HTO and were able to participate in competitions at the same activity level as before surgery was low and insufficient. LEVEL OF EVIDENCE: Retrospective case series, IV.
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PURPOSE: The concept of medial stabilizing technique total knee arthroplasty (MST-TKA) is to minimize the medial release without the superficial layer of medial collateral ligament (MCL). However, it is unclear at what stage the proper medial laxity is obtained during surgery. The purpose of this study was to investigate the implication of deep layer of MCL (dMCL) and osteophyte resection on medial laxity during MST-TKA. METHODS: A total of 103 consecutive patients who underwent cruciate-retaining TKA using the navigation system were included. The intraoperative hip-knee-ankle (HKA) angle was recorded under three conditions (no stress, valgus, and varus stress) at four time points after the resection of the anterior cruciate ligament (ACL) and meniscus (1st evaluation), after the dMCL release (2nd evaluation), and after osteophyte resection on both the femoral and tibial side (3rd evaluation). To assess valgus laxity, the differences in intraoperative HKA angle between 1st and 2nd evaluation (stage 1) and between 2nd and 3rd evaluation (stage 2) were calculated. RESULTS: Under the valgus stress condition, the intraoperative HKA angle change in stage 2 was significantly larger than that in stage 1 in full extension (stage 1; - 0.5 ± 1.0°, stage 2; - 2.0 ± 1.3°, p < 0.001) and 30° flexion (stage 1; - 0.8 ± 1.4°, stage 2; - 1.5 ± 2.0°, p = 0.008). There were no significant differences at 60° and 90° of knee flexion. Under the no stress and varus stress conditions, there were no significant differences in knee flexion at all angles. CONCLUSION: The medial laxity during MST-TKA increased significantly more after dMCL release and osteophyte resection than after just dMCL release at full extension and 30° flexion, and it was, therefore, considered that osteophyte resection is a key procedure for a successful MST-TKA. LEVEL OF EVIDENCE: Level II, therapeutic prospective cohort study.
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Artroplastia de Reemplazo de Rodilla , Inestabilidad de la Articulación , Ligamento Colateral Medial de la Rodilla , Osteoartritis de la Rodilla , Osteofito , Fenómenos Biomecánicos , Humanos , Inestabilidad de la Articulación/cirugía , Articulación de la Rodilla/cirugía , Ligamento Colateral Medial de la Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Osteofito/cirugía , Estudios Prospectivos , Rango del Movimiento ArticularRESUMEN
BACKGROUND: Appropriate postoperative lower limb alignment is one important element of a successful unicompartmental knee arthroplasty (UKA). To predict postoperative alignment, it is important to investigate the association between preoperative imaging evaluations and lower limb alignment after medial UKA. QUESTIONS/PURPOSES: (1) Do preoperative valgus stress radiographic and MRI measurements (% mechanical axis, hip-knee-ankle angle, medial meniscal extrusion distance, and osteophyte area at the medial femur and tibia) correlate with postoperative lower limb alignment after UKA; and (2) Can useful cutoffs be calculated in advance of surgery for those findings that were associated with coronal-plane overcorrection? METHODS: We retrospectively analyzed 125 patients with medial knee pain who underwent UKA from January 2012 to October 2018. Valgus stress radiography and MRI were performed routinely to assess the knee. Valgus stress radiography was obtained with the patient supine with the knee in full extension and a firm manual valgus force applied to the knee. Full-length weightbearing radiography was performed 3 months after surgery. There were 12% (15) of patients who did not undergo MRI, and 4% (five) of patients who did not receive the postoperative full-length weightbearing radiograph and they were excluded, leaving 84% (105) of patients available for analysis. There were 27 men and 78 women with a mean (range) age of 77 years ± 6 years (60 to 87). The preoperative diagnosis was medial osteoarthritis in 99 patients and osteonecrosis of the medial femoral condyle in six. To investigate the associations, we routinely measured % mechanical axis using radiography, and also measured the medial meniscal extrusion distance and osteophyte area at the medial femur and tibia using MRI after surgery. Medial meniscus extrusion distance was defined as the distance from the outermost edge of the medial meniscus to a line connecting the femoral and tibial cortices. From these parameters, postoperative alignment was estimated using regression and receiver operating characteristic curve analyses. Variables with p < 0.05 were included. RESULTS: The % mechanical axis on the valgus stress radiograph and medial meniscal extrusion distance were correlated with postoperative lower limb alignment after UKA (adjusted correlation coefficient 0.72; p < 0.001, adjusted correlation coefficient 0.2; p = 0.003, respectively). The estimated % mechanical axis on the postoperative weightbearing radiograph was equal to -0.27 + 0.86% (% mechanical axis on valgus stress radiograph) + 1.14 mm (medial meniscal extrusion distance). Using a cutoff point of 36%, the % mechanical axis on valgus stress radiograph was associated with overcorrection after UKA (area under the curve: 0.89; odds ratio 14 [95% CI 0.75 to 0.95]; p < 0.001, sensitivity 77.8%, specificity 80.9%). CONCLUSIONS: The overcorrection of a varus knee on a valgus stress radiograph before UKA and the increased extrusion of the medial meniscus on preoperative MRI was associated with a greater likelihood of overcorrected alignment after UKA. Future studies should conduct long-term follow-up of malalignment patients to assess the possible complications. LEVEL OF EVIDENCE: Level III, diagnostic study.
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Artroplastia de Reemplazo de Rodilla , Articulación de la Rodilla/cirugía , Meniscos Tibiales/cirugía , Osteoartritis de la Rodilla/cirugía , Osteonecrosis/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/fisiopatología , Imagen por Resonancia Magnética , Masculino , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/fisiopatología , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/fisiopatología , Osteonecrosis/diagnóstico por imagen , Osteonecrosis/fisiopatología , Posicionamiento del Paciente , Rango del Movimiento Articular , Recuperación de la Función , Estudios Retrospectivos , Posición Supina , Factores de Tiempo , Resultado del Tratamiento , Soporte de PesoRESUMEN
BACKGROUND: Posterior osteophyte of the femur can impinge on the tibia insert in total knee arthroplasty (TKA). Although osteophyte removal [posterior clearance (PC)] improves the flexion angle, its influence on the gaps and extension angle are unclear. This study investigated the effect of PC on the gaps and range of motion (ROM) using a navigation system, as well as PC's relationship with osteophyte size. METHODS: Twenty-seven knees that underwent cruciate-retaining (CR)-type TKA were examined. Before and after PC, the ROM, hip-knee-ankle (HKA) angle, and flexion and extension gaps were recorded using a navigation system. Osteophyte size was measured in the lateral view in radiographs, and in the sagittal and axial planes of computed tomography (CT) images. The effects of PC on the gaps and ROM were analysed statistically. RESULTS: PC caused the extension gap to increase by 0.7 ± 0.9 mm in the medial (p < 0.001), and 0.9 ± 1.5 mm in the lateral compartment (p = 0.006). The extension angle increased by 4.9 ± 1.6°, flexion angle increased by 6.5 ± 5.0°, and HKA decreased by 0.3°. The increase in extension angle by PC was significantly correlated with the preoperative HKA angle (r = 0.594) and with the osteophyte area in radiographs and CT (r = 0.626 to 0.681). CONCLUSIONS: The extension and flexion gaps increased less than 1 mm in the medial and lateral compartments. PC achieving an additional 5° extension angle could promote full extension in severely deformed knees with a large posterior osteophyte. The extension angle increase by PC was correlated with the preoperative HKA angle and osteophyte size.
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Ligamento Cruzado Anterior , Artroplastia de Reemplazo de Rodilla/métodos , Osteofito/cirugía , Ligamento Cruzado Posterior , Cirugía Asistida por Computador/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteofito/diagnóstico por imagen , Rango del Movimiento ArticularRESUMEN
Study Design: Retrospective study. Purpose: We experienced the situation wherein some patients had new-onset pain or dysesthesia around the ring and little fingers (C8 symptom) or ulnar aspect of the forearm (T1 symptom) after cervical laminoplasty (LP). We investigated the incidence and the cause of new C8 or T1 symptoms and the clinical outcomes after C3-C6 LP or C3-C7 LP. Overview of Literature: There were some reports regarding complications after cervical LP. However, there was no report regarding C8 or T1 symptoms after cervical LP. Methods: Among the 33 patients enrolled in this study, 11 and 22 patients were treated with C3-C6 LP and C3-C7 LP, respectively. We prospectively evaluated C8 or T1 symptoms daily postoperatively for 1 week. The distance of the posterior spinal cord shifting and posterior subarachnoid space from C2 to T1 was measured by T2-weighted midsagittal magnetic resonance imaging (MRI). We evaluated pre- and postoperative axial neck pain, Japanese Orthopaedic Association (JOA) score, and JOA score improvement rate. Results: C8 or T1 symptoms occurred in five and three patients with C3-C6 LP (45.5%) and C3-C7 LP (13.6%), respectively. The distance of the posterior subarachnoid space in C3-C6 LP at C7 was significantly shorter than that in C3-C7 LP at T1 on MRI 24 hours postoperatively (p=0.0448). Postoperative axial neck pain, pre- and postoperative JOA scores, and JOA score improvement rate were not significantly different. Conclusions: The incidence of C8 or T1 symptoms in C3-C6 LP was higher than that in C3-C7 LP. C8 or T1 symptoms would be caused by the posterior fila radicularia and spinal cord impingement on the intact lower end of the lamina.
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Surface heat flow has been observed to be highly variable in the Nankai subduction margin. This study presents an investigation of local anomalies in surface heat flows on the undulating seafloor in the Nankai subduction margin. We estimate the heat flows from bottom-simulating reflectors (BSRs) marking the lower boundaries of the methane hydrate stability zone and evaluate topographic effects on heat flow via two-dimensional thermal modeling. BSRs have been used to estimate heat flows based on the known stability characteristics of methane hydrates under low-temperature and high-pressure conditions. First, we generate an extensive map of the distribution and subseafloor depths of the BSRs in the Nankai subduction margin. We confirm that BSRs exist at the toe of the accretionary prism and the trough floor of the offshore Tokai region, where BSRs had previously been thought to be absent. Second, we calculate the BSR-derived heat flow and evaluate the associated errors. We conclude that the total uncertainty of the BSR-derived heat flow should be within 25%, considering allowable ranges in the P-wave velocity, which influences the time-to-depth conversion of the BSR position in seismic images, the resultant geothermal gradient, and thermal resistance. Finally, we model a two-dimensional thermal structure by comparing the temperatures at the observed BSR depths with the calculated temperatures at the same depths. The thermal modeling reveals that most local variations in BSR depth over the undulating seafloor can be explained by topographic effects. Those areas that cannot be explained by topographic effects can be mainly attributed to advective fluid flow, regional rapid sedimentation, or erosion. Our spatial distribution of heat flow data provides indispensable basic data for numerical studies of subduction zone modeling to evaluate margin parallel age dependencies of subducting plates.
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PURPOSE: Evaluations for knee osteoarthritis (OA) or post-operative total knee arthroplasty (TKA) have mainly been assessed by objective scales. Though the Knee injury and Osteoarthritis Outcome Score (KOOS) is attracting attention as a patient-based outcome score, the relationship with conventional objective scales after TKA remains controversial. The purpose of this study was to investigate the relationship between KOOS and conventional objective scales and evaluate the features of patient-based outcome scores. METHODS: Subjects were 130 post-operative patients involving 186 knees treated with TKA. Their mean age was 74.0 ± 8.0 years, and the follow-up period was 43 months. Japanese Orthopaedic Association (JOA) score, original Knee Society Score (KSS) and surgeon's satisfaction score were scored as conventional objective scales besides KOOS. Spearman's correlation coefficient was estimated between these scales. Comparisons between OA and rheumatoid arthritis (RA) as well as primary and revision surgery were performed by the Mann-Whitney U test. RESULTS: There were strong correlations between KOOS activities of daily living (ADL) and JOA score (r = 0.806), KSS function score (r = 0.803) and between KOOS pain and KSS knee score (r = 0.689). However, there was a poor correlation between KOOS and surgeon's satisfaction score (r = 0.188-0.321). TKA for RA showed poorer results only in KOOS pain (p = 0.003), and revision surgery showed poorer results in KSS function, KOOS symptoms and KOOS quality of life (QOL). CONCLUSIONS: This study suggested that conventional objective scales reflected mainly ADL disturbances in post-operative TKA patients. Furthermore, patient-based outcome scores made it possible to evaluate and detect a minute change of knee pain and QOL in TKA patients. The Japanese KOOS was a useful tool to evaluate conditions after TKA.
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Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla/cirugía , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación del Resultado de la Atención al Paciente , Autoinforme , Encuestas y Cuestionarios , Anciano , Anciano de 80 o más Años , Artralgia/epidemiología , Femenino , Humanos , Incidencia , Japón , Articulación de la Rodilla/diagnóstico por imagen , Masculino , Periodo Posoperatorio , Calidad de Vida , Radiografía , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
In severe varus knee deformity, image-free computer navigated total knee arthroplasty (TKA) may result in a malaligned knee. The aim of this study was to compare the results of 17 severe varus knees (≥ 20°) and 81 varus knees (< 20°) that underwent image-free computer navigated TKA and analyze postoperative malalignment. Computer navigated TKA was performed according to standard protocol, and component angles and mechanical axes were evaluated postoperatively with weight bearing full-length standing radiographs. All severe varus knees were corrected to within 3° of neutral lower limb alignment despite having a mean preoperative varus deformities of 22.4°. Neutral alignment was obtained in 88.9% of the varus group (mean preoperative varus deformity of 11.7°), without significant difference between the two groups. No significant difference was found in either the femoral or tibial component angles, or in the frequency of complications. Severity of varus deformity did not affect the accuracy of image-free computer navigated TKA.
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Artroplastia de Reemplazo de Rodilla/métodos , Desviación Ósea/complicaciones , Cirugía Asistida por Computador , Anciano , Desviación Ósea/diagnóstico por imagen , Femenino , Humanos , Masculino , Radiografía , Cirugía Asistida por Computador/métodos , Resultado del TratamientoRESUMEN
STUDY DESIGN: A prospective study in 19 patients after cervical laminoplasty, using magnetic resonance imaging. OBJECTIVE: To evaluate the value of spinal cord shift at 24 hours after cervical laminoplasty. SUMMARY OF BACKGROUND DATA: Postoperative C5 palsy is a noticeable complication within 1 week after cervical laminoplasty. The root tethering due to the posterior shift of the spinal cord after laminoplasty was reported as one of the causes of C5 palsy. However, the spinal cord shift after surgery within 1 week is unknown. METHODS: The posterior shift of the spinal cord was measured in 19 consecutive patients on magnetic resonance images at 24 hours and 2 weeks after cervical laminoplasty. RESULTS: The mean posterior shift of the spinal cord at 24 hours was 2.8 mm, with the maximum at the C5 level, decreasing to 1.9 mm at 2 weeks. The posterior shift of the spinal cord at C5 was correlated with the amount of the dura mater at C4, C5, and C6 levels. In a patient with right C5 palsy, posterior shift at C5 level was 5.5 mm, decreasing to 3.0 mm at 2 weeks after surgery. The posterior shift of the spinal cord was not correlated with the sagittal alignment. CONCLUSION: The posterior shift of the spinal cord at 24 hours had a tendency to shift more posteriorly than that observed at 2 weeks after cervical laminoplasty. C5 palsy may be prevented if the expansion of dura mater, which is strongly correlated with the posterior shift, can be controlled.
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Neuropatías del Plexo Braquial/etiología , Laminectomía/efectos adversos , Complicaciones Posoperatorias/etiología , Radiculopatía/etiología , Médula Espinal/fisiopatología , Espondilosis/cirugía , Anciano , Anciano de 80 o más Años , Neuropatías del Plexo Braquial/fisiopatología , Neuropatías del Plexo Braquial/prevención & control , Descompresión Quirúrgica/efectos adversos , Descompresión Quirúrgica/métodos , Progresión de la Enfermedad , Duramadre/patología , Duramadre/fisiopatología , Edema/complicaciones , Edema/patología , Edema/fisiopatología , Femenino , Humanos , Laminectomía/métodos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Parálisis/etiología , Parálisis/fisiopatología , Parálisis/prevención & control , Complicaciones Posoperatorias/fisiopatología , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos , Radiculopatía/fisiopatología , Radiculopatía/prevención & control , Médula Espinal/anatomía & histología , Raíces Nerviosas Espinales/lesiones , Raíces Nerviosas Espinales/patología , Raíces Nerviosas Espinales/fisiopatología , Factores de Tiempo , Extremidad Superior/inervación , Extremidad Superior/fisiopatologíaRESUMEN
PURPOSE: The purpose of this study was to compare the effects of local and general fatigue loads on knee proprioception. TYPE OF STUDY: Experimental controlled study. METHODS: Proprioception of the knee joint was evaluated by measuring absolute angular error (AAE) at matching defined index angles before and after 2 different types of fatigue protocols (local load and general load) in 27 healthy male volunteers. Local load was provided with maximum isokinetic knee flexion-extension on the isokinetic dynamometer, and general load was 5 minutes running on a treadmill. RESULTS: After local load, a significant decrease in peak torque of knee flexors and extensors was found, but no significant change in AAE was seen. In contrast, after general load, a significant increase of AAE was noted without significant muscle weakness. CONCLUSIONS: The different results in previous studies evaluating the effect of fatigue on knee proprioception may have been affected by the difference of fatigue protocols, whether local or general load. Although local load was intended to produce local fatigue of the knee, which may cause dysfunction of muscle mechanoreceptors, general load may have produced general fatigue and affected other mechanisms in the proprioceptional pathway. The results of the present study suggest that decreased reproduction ability after general load is not due to the loss of peripheral afferent signals, but to other factors, especially deficiency of central processing of proprioceptive signals. CLINICAL RELEVANCE: To prevent knee injury caused by fatigue-induced proprioceptional decline, muscle endurance training alone is not enough, and neuromuscular training, including central motor programming, is essential.
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Fatiga/psicología , Articulación de la Rodilla , Propiocepción , Adulto , Fenómenos Biomecánicos , Encéfalo/fisiología , Humanos , Traumatismos de la Rodilla/prevención & control , Masculino , Mecanorreceptores/fisiología , Movimiento , Contracción Muscular , Especificidad de Órganos , Resistencia Física , Modalidades de Fisioterapia , Propiocepción/fisiología , Torque , Soporte de PesoRESUMEN
The purpose of this study was to assess the influences of surgical approaches and tourniquet application on the lateral retinacular tension (LRT). Single-setting bilateral total knee arthroplasty was performed in 10 patients, and the medial parapatellar and midvastus approaches were randomly performed on each knee using tourniquet application. The LRT was measured using the buckle transducer before and after each approach. Next, the tourniquet was deflated and the measurement was repeated. After the parapatellar approach, LRT was significantly decreased. Conversely, no significant change was seen after the midvastus approach with the tourniquet inflated. However, in the midvastus approach, LRT was significantly decreased after tourniquet deflation. We concluded that both the parapatellar and midvastus approaches influence patellar tracking and LRT.
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Artroplastia de Reemplazo de Rodilla/métodos , Hemostasis Quirúrgica/métodos , Ligamento Rotuliano/fisiología , Torniquetes , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Hemostasis Quirúrgica/instrumentación , Humanos , Articulación de la Rodilla/fisiología , Masculino , Persona de Mediana Edad , Movimiento , Estrés MecánicoRESUMEN
BACKGROUND: Anatomic fixation of the graft in anterior cruciate ligament reconstruction has improved stability of the reconstructed knee joint in experimental studies. HYPOTHESIS: Anatomic fixation of the bone-patellar tendon-bone autograft will reduce tunnel enlargement and improve clinical results. STUDY DESIGN: Prospective cohort study. METHODS: Sixty patients were randomly divided into three groups: a nonanatomic fixation group (traditional single-incision reconstruction), an anatomic fixation group (reconstruction in which a bone plug was grafted into the tibial tunnel), and an anatomic fixation group with all-inside reconstruction. Stability of the knee joint was examined with a KT-1000 arthrometer at 2, 4, 6, 12, and 24 months after surgery. At 12 months, anteroposterior and lateral radiographs were made to assess tunnel enlargement. RESULTS: Although the magnitude of tibial displacement gradually increased after reconstruction in all three groups, the anatomic fixation group had significantly better stability than the groups undergoing nonanatomic fixation or all-inside anatomic fixation at 4 and 6 months after anterior cruciate ligament reconstruction. However, there was no significant difference between the three groups at 24 months. Regarding the tibial tunnel, residual rates and enlargement of tunnels were different between the reconstruction techniques. The nonanatomic reconstruction group had significantly greater tunnel enlargement. CONCLUSION: Anatomic fixation of the graft decreased the tunnel enlargement but had no effect on knee stability at 2-year follow-up.
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Ligamento Cruzado Anterior/cirugía , Procedimientos Ortopédicos/métodos , Rótula/cirugía , Tendones/trasplante , Tibia/cirugía , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior , Tornillos Óseos , Estudios de Cohortes , Femenino , Humanos , Inestabilidad de la Articulación/fisiopatología , Inestabilidad de la Articulación/cirugía , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Rango del Movimiento Articular/fisiología , Resultado del TratamientoRESUMEN
OBJECTIVE: To compare findings of radiography, scintigraphy, and magnetic resonance imaging (MRI) in stress injuries of bone and evaluate changes of these findings with time correlated with clinical symptoms. DESIGN: Prospective study. SETTING: A primary care hospital outpatient orthopedic clinic. PATIENTS: All 31 patients with stress injuries of bone who visited our clinic from July 1996 to June 2000. INTERVENTION: Radiography, scintigraphy, MRI, and clinical examinations were performed on the same day or at least within 1 week of each other, and the findings were compared. If symptoms of stress injury of bone continued, these examinations were repeated at intervals of 2 months until symptoms disappeared. These radiologic findings were assessed by an independent radiologist who was blinded to the clinical symptoms of the patients. MAIN OUTCOME MEASURES: Correlation accuracy of MRI and scintigraphy findings with clinical symptoms. RESULTS: Even with negative initial radiographic findings, all initial scintigraphy and MRI indicated stress injury of bone. There were no patients with positive/negative examinations. Grade of scintigraphy and MRI were closely correlated, and these findings also correlated with the degree of clinical symptoms. Compared with scintigraphy, MRI showed more diagnostic information, such as fracture line and periosteal edema. Areas of increased activity in scintigraphy were consistent with the grades of MRI, especially high signal intensity areas of STIR (short tau inversion recovery) image. CONCLUSIONS: From these observations, MRI is less invasive, provides more information than scintigraphy, and is recommended for initial diagnosis and assessment stages of stress injury of bone.
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Traumatismos en Atletas/diagnóstico por imagen , Traumatismos en Atletas/diagnóstico , Fracturas por Estrés/diagnóstico por imagen , Fracturas por Estrés/diagnóstico , Imagen por Resonancia Magnética , Adolescente , Adulto , Traumatismos en Atletas/fisiopatología , Niño , Femenino , Fracturas por Estrés/fisiopatología , Humanos , Japón , Masculino , Estudios Prospectivos , Cintigrafía , DeportesRESUMEN
The patellar retinaculum is important in patellar tracking. However, little attention has been paid to the biomechanics of the retinaculum. This study assessed the change in tension of the lateral patellofemoral ligament before and after anteromedial tibial tubercle transfer for patellar instability. Twenty-seven knees in 21 patients were studied and the mean age of the patients at surgery was 19 years. A buckle transducer was clamped on the lateral patellofemoral ligament and the transducer was calibrated to zero with the knee at full extension. The knee then was flexed 30 degrees, 60 degrees, 90 degrees, and 120 degrees, and the transducer recorded changes in tension within the lateral patellofemoral ligament. After anteromedial tibial tubercle transfer, lateral patellofemoral ligament tension was measured in the same manner. Although average lateral patellofemoral ligament tension increased with knee flexion with the maximum at 120 degrees flexion, these changes showed four different patterns measuring variability of patellar instability. An increase of lateral patellofemoral ligament tension after anteromedial tibial tubercle transfer meant that lateral retinacular release should be done concurrently to balance patellar tracking. This information may be useful in deciding the appropriate surgical procedure for each patient.