股骨髁间窝成形术防止胫骨高位截骨术后髁间窝撞击的临床研究

目的:观察髁间窝成形术预防胫骨高位截骨术后髁间窝撞击的临床疗效。方法:自2018年8月至2020年8月,采用关节镜联合胫骨高位截骨手术治疗84例内翻型膝骨关节炎患者,按照手术方法不同分为两组,每组42例。髁间窝成形术组男13例,女29例,年龄52~67(58.27±4.32)岁,先在关节镜下行髁间窝成形术,再行胫骨高位截骨术。镜下清理术组男16例,女26例,年龄50~71(59.02±5.14)岁,单纯行关节镜下清理术,再行胫骨高位截骨术。术后采用疼痛视觉模拟评分(visual analogue scale,VAS)、膝关节特种外科医院(hospital of special surgery,HSS)评分以及发生髁间窝撞击的情况对临床疗效进行评估。结果:84例患者均获得随访,时间12~18(14.1±1.6)个月。术后6、12、18个月膝关节VAS与HSS评分均较术前明显改善(P<0.05),术后18个月两组患者髁间窝指数、髁间窝撞击发生率比较,差异有统计学意义(P<0.05)。结论:髁间窝成形术可有效预防胫骨高位截骨术后髁间窝撞击的发生率,对患者术后膝关节疼痛及功能改善效果更为显著。     

关节镜下治疗股骨髁间窝退变性狭窄症

目的探讨关节镜监视下股骨髁间窝狭窄症的疗效。方法自2001年6月～2006年6月通过关节镜下诊断和治疗股骨髁间窝退变性狭窄症59例。所有病例均行镜下股骨髁间窝扩大成形术,18例行前交叉韧带紧缩术,以Lysholm评分评价比较手术前后膝关节功能。结果镜下所见：股骨髁间窝外侧髁骨突撞击46例,内侧髁骨突撞击5例,内、外侧髁均撞击5例,髁间窝前缘撞击3例;受撞击前交叉韧带相应部位有不同程度的磨损及纤维断裂。52例获得15．48个月随访,术后检查患者关节屈伸功能基本正常,根据Lysholm评分系统评估关节功能,关节功能由术前76．5±4．5提高到96．7±3．8,差异有统计学意义（T=4．874,P〈O．05）。结论关节镜技术具有损伤小、术后康复快、疗效确切等优点,是诊治股骨髁间窝退变性狭窄症最直接有效的手段。     

关节镜对膝关节髁间痛的诊治

[目的]探讨关节镜下膝关节髁间痛的病因并作出分型，根据不同的分型作出不同的治疗。[方法]对16例以髁间痛为主要症状患者的临床表现、X线等影像资料和关节镜下表现结合，进行总结后分型，并行关节镜下微创治疗。[结果]膝关节髁间痛可分为6种类型：股骨髁间窝狭窄型；胫骨髁间嵴增高型；胫骨前交叉韧带起点骨赘增生型；关节内游离体嵌顿型；滑膜过度增生型；混合型。关节镜下能将狭窄的髁间窝扩大成形，增生骨赘去除，游离体摘除，增生滑膜刨削。经过2～14个月的随访，髁间痛明显缓解或消失。根据Lysholm评分，由术前51．7分增加至89．7分。[结论]关节镜微创术是治疗膝关节髁间痛的有效方法。     

Cartilage Damage Is Related to ACL Stiffness in a Porcine Model of ACL Repair

Inferior anterior cruciate ligament (ACL) structural properties may inadequately restrain tibiofemoral joint motion following surgery, contributing to the increased risk of post‐traumatic osteoarthritis. Using both a direct measure of ACL linear stiffness and an in vivo magnetic resonance imaging (MRI) T₂*‐based prediction model, we hypothesized that cartilage damage and ACL stiffness would increase over time, and that an inverse relationship between cartilage damage and ACL stiffness would emerge at a later stage of healing. After either 6, 12, or 24 weeks (w) of healing after ACL repair, ACL linear stiffness was determined from the force–displacement relationship during tensile testing ex vivo and predicted in vivo from the MRI T₂*‐based multiple linear regression model in 24 Yucatan minipigs. Tibiofemoral cartilage was graded postmortem. There was no relationship between cartilage damage and ACL stiffness at 6 w (R² = 0.04; p = 0.65), 12 w (R² = 0.02; p = 0.77), or when the data from all animals were pooled (R² = 0.02; p = 0.47). A significant inverse relationship between cartilage damage and ACL stiffness based on both ex vivo measurement (R² = 0.90; p < 0.001) and in vivo MRI prediction (R² = 0.78; p = 0.004) of ACL stiffness emerged at 24 w. This result suggests that 90% of the variability in gross cartilage changes is associated with the repaired ACL linear stiffness at 6 months of healing. Clinical Significance: Techniques that provide a higher stiffness to the repaired ACL may be required to mitigate the post‐traumatic osteoarthritis commonly seen after ACL injury, and MRI T₂* can be used as a noninvasive estimation of ligament stiffness. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2249–2257, 2019     

T2* MR relaxometry and ligament volume are associated with the structural properties of the healing ACL

Our objective was to develop a non‐invasive magnetic resonance (MR) method to predict the structural properties of a healing anterior cruciate ligament (ACL) using volume and T₂* relaxation time. We also compared our T₂*‐based structural property prediction model to a previous model utilizing signal intensity, an acquisition‐dependent variable. Surgical ACL transection followed by no treatment (i.e., natural healing) or bio‐enhanced ACL repair was performed in a porcine model. After 52 weeks of healing, high‐resolution MR images of the ACL tissue were collected. From these images, ligament volumes and T₂* maps were established. The structural properties of the ligaments were determined via tensile testing. Using the T₂* histogram profile, each ligament voxel was binned based on its T₂* value into four discrete tissue sub‐volumes defined by specific T₂* intervals. The linear combination of the ligament sub‐volumes binned by T₂* value significantly predicted maximum load, yield load, and linear stiffness (R² = 0.92, 0.82, 0.88; p < 0.001) and were similar to the previous signal intensity based method. In conclusion, the T₂* technique offers a highly predictive methodology that is a first step towards the development of a method that can be used to assess ligament healing across scanners, studies, and institutions. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:492–499, 2014.     

评价成人前交叉韧带损伤与髁间窝形态的关系:一项高分辨率MRI研究

[目的]分析髁间窝形态与前交叉韧带(anterior cruciate ligament,ACL)损伤风险的关系。[方法]回顾兰州大学第二医院2013年6月~2015年1月期间收治的150例符合纳入标准的ACL损伤患者作为病例组,平均年龄36.3岁(18~60岁),男女比例为1.4:1。对照组为按照年龄、性别与病例组1:1配对的参加体检的健康人群,共150例。分别在膝关节高分辨率MRI冠状位和轴位扫描图像上测量髁间窝宽度、股骨双髁宽度,统计髁间窝分型,计算髁间窝宽度指数(notch width index,NWI)。[结果]髁间窝宽度、NWI单变量Logistic回归分析结果:轴位髁间窝宽度[OR=0.865,95%CI(0.784,0.955),P=0.004]和冠状位髁间窝宽度[OR=0.879,95%CI(0.813,0.851),P=0.001]是ACL损伤的危险因素,轴位NWI[OR=0.000 02,95%CI(0.000,0.008),P=0.002]和冠状位NWI[OR=0.000 2,95%CI(0.000,0.010),P=0.001]是ACL损伤的高度危险因素。对病例组和对照组髁间窝分型的χ2检验结果显示:在男性女性合并的总体中两组分型无差异(P=0.792),但在女性中两组分型有显著性差异(P=0.025)。[结论]髁间窝宽度和NWI是ACL损伤的危险因素,其中NWI是高危因素;病例组和对照组的髁间窝分型在总体中无差异,但在女性中A型髁间窝可增加ACL损伤的风险。     

Double-band reconstruction of the ACL using a synthetic implant: a cadaveric study of knee laxity

In this study, the anterior laxity and internal rotation of five cadaveric knee joints were compared when the anterior cruciate ligament (ACL) was intact, after its reconstruction with the anteromedial band (AMB) only, then after its reconstruction with the double band, with the posterolateral band (PLB) tensioned first at 20° and then at 90°, and finally with the ACL resected. The tests were performed using a mechanical apparatus that allowed the joint 6° of freedom and also the application of external loads and torques on the tibia. The loads used were 50, 90, and 130N for the anterior laxity test, and a torque of 2, 3, and 4Nm in the internal rotation test. In all cases, laxity with double-band reconstruction was closer to the natural value than when it was constructed with the AMB only. In some cases, double-band reconstruction imposed a higher constraint on the joint than did the natural ACL. Measurement of the residual tension on the PLB after its final anchoring was also performed during passive flexion. This test revealed a high tension on this band with the knee in hyperextension, followed by a decrease in value through to 45° and a slight increase at 90°, thus following a similar trend to that of the natural PLB.     

The use of platelets to affect functional healing of an anterior cruciate ligament (ACL) autograft in a caprine ACL reconstruction model

Many anterior cruciate ligament (ACL) reconstructions have increased laxity postoperatively. We hypothesized that enhancing an ACL graft with a collagen‐platelet composite (CPC) would improve knee laxity and graft structural properties. We also hypothesized the platelet concentration in the CPC would affect these parameters. Twelve goats underwent ACL reconstruction with autologous patellar tendon graft. In six goats, a collagen‐platelet composite was placed around the graft (CPC group). In the remaining six goats, the collagen scaffold only was used (COLL group). Three goats were excluded due to complications. After 6 weeks in vivo, anterior–posterior (AP) laxity and tensile properties of the ACL reconstructed knees were measured and normalized against the contralateral intact knee. At a knee flexion angle of 30°, the average increase in AP laxity was 40% less in the CPC group than the COLL group (p = 0.045). At 60°, the AP laxity was 30% less in the CPC group, a difference that was close to statistical significance (p = 0.080). No differences were found between treatment groups with respect to the structural properties (p > 0.30). However, there were significant correlations between serum platelet concentration and AP laxity (R² = 0.643; p = 0.009), maximum load (R² = 0.691; p = 0.006), and graft stiffness (R² = 0.840; p < 0.001). In conclusion, use of a CPC to enhance healing of an allograft ACL reconstruction inversely correlated with early sagittal plane laxity and the systemic platelet count was highly predictive of ACL reconstruction graft strength and stiffness at 6 weeks. These findings emphasize the importance of further research on delineating the effect of platelets in treating of ACL injuries. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 631–638, 2009     

Magnetic resonance measurements of tissue quantity and quality using T2* relaxometry predict temporal changes in the biomechanical properties of the healing ACL

The purpose of this study was to develop a magnetic resonance T₂* relaxometry‐based multiple linear regression model to predict the structural properties of the healing anterior cruciate ligament (ACL) over a 24‐week healing period following ACL repair in Yucatan minipigs. Two hypotheses were tested: (i) that a regression model based on ACL sub‐volumes containing short and long T₂* relaxation times would outperform a competing model based on sub‐volumes of short T₂* relaxation times only; and (ii) that an optimized regression model would be capable of predicting ACL structural properties between 6 and 24 weeks post‐repair. ACLs were imaged in 24 minipigs (8/group) at either 6, 12, or 24 weeks after ACL repair. The structural properties of the ACLs were determined from tensile failure tests. Four multiple linear regression models of increasing complexity were fitted to the data. Akaike Information Criterion values and Bland–Altman tests were used to compare model performance and to test the hypotheses. The structural properties predicted from the multiple linear regression model that was based on the change in ACL sub‐volumes of both the short and long T₂* relaxation times over the healing period were in closest agreement to the measured values, suggesting that the amounts of both organized and disorganized collagen, and the change in these quantities over time, are required to predict the structural properties of healing ACLs accurately. Clinical significance: our time‐specific, T₂*‐based regression model may allow us to estimate the structural properties of ACL repairs in vivo longitudinally. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1701–1709, 2018.     

Femoral bridge stability in double-bundle ACL reconstruction: impact of bridge width and different fixation techniques on the structural properties of the graft/femur complex

Background  The aim of this study was to evaluate the impact of different widths of the bony bridge between the femoral AM and PL bundle tunnel and different fixation techniques on the structural properties of the graft/femur complex in double-bundle ACL reconstructions. Hypothesis  Double-bundle ACL reconstruction with a bony bridge between AM and PL bundle tunnel of 1 mm results in significantly lower structural properties of the graft/femur complex when compared to a bridge of 2 and 3 mm. Interference screw fixation significantly lowers the structural properties when compared to cortical fixation. Study design  Controlled laboratory study. Methods  Double-bundle ACL reconstructions using different bridge widths (1 mm, 2 mm, and 3 mm bridge) were loaded to failure after a cyclic loading protocol (1,000 cycles 0–200 N) and the structural properties were compared to a single-bundle ACL reconstruction group (n = 10 in each group). The structural properties of using a cortical button fixation were then compared to interference screw fixation (2 mm bridge). Statistical analyses were performed using a Mann–Whitney test (P < 0.05). Results  Double-bundle reconstructions with cortical button fixation (1, 2, and 3 mm bridge) showed significantly higher ultimate failure loads and stiffness and significantly lower elongation compared to single-bundle reconstructions. Double-bundle ACL reconstructions with a 1 mm bridge showed significantly reduced structural properties of the graft/femur complex compared to a 2 or 3 mm bridge. Aperture fixation led to significantly lower ultimate loads when compared to cortical fixation. Conclusion  The bony bridge between the two femoral tunnels in double-bundle ACL reconstructions influences the stability of the graft/femur complex. Aperture fixation using interference screws shows inferior results when compared to cortical fixation. Clinical relevance  The results suggest that the indication for anatomical ACL reconstruction may include the size of the lateral femoral condyle. In small knees, a second femoral tunnel may be difficult to locate with a minimum bridge width of 2 mm.     

T2* relaxometry and volume predict semi‐quantitative histological scoring of an ACL bridge‐enhanced primary repair in a porcine model

Magnetic resonance imaging (MRI) variables, such as T₂* and volume, can predict the healing ligament structural properties. How these MR variables relate to semi‐quantitative histology of the healing ACL is yet unknown. We hypothesized that T₂* and volume would predict the histological scoring of a healing ACL. Yucatan minipigs underwent ACL transection and received bridge‐enhanced ACL repair or no treatment. The surgical legs were harvested after 52 weeks and imaged using a high resolution 2‐echo sequence. For each ligament, the volume and median T₂* values were determined. The ACL specimens were then histologically analyzed using the advanced Ligament Maturity Index (LMI). The T₂* of the healing ligaments significantly predicted the total LMI score as well as the cell, collagen and vessel sub‐scores; R² = 0.78, 0.67, 0.65, and 0.60, respectively (p ≤ 0.001). The ligament volume also predicted the total LMI score, cell, and collagen sub‐scores; R² = 0.39, 0.33, 0.37, and 0.60, respectively (p ≤ 0.001). A lower ligament T₂* or a higher volume was associated with higher histological scores of the healing ligaments. This study provides a critical step in the development of a non‐invasive method to evaluate ligament healing on a microscopic scale. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1180–1187, 2015.     

Correlation of MR images of disc injuries with anatomic sections in experimental thoracolumbar spine fractures

This cadaver study evaluated the value of MR images for detection of acute intervertebral disc damage associated with fractures of the thoracolumbar spine. Damage to the intervertebral disc may be a major contributor to chronic instability in non-operative treatment or failure of fixation and recurrence of deformity in posterior fixation methods. MR imaging can help us to understand the injury patterns and their prognostic significance. However, before we can justify the use of MRI in clinical cases, determination of MRI’s ability to detect acute injury to the disc is necessary. Ten fresh cadaver specimens were used for this study. After obtaining radiograms and MR images, injuries were created with a weight-dropping apparatus using a variety of weights and compression angles. Post-injury radiograms and MR images were taken and the specimens were frozen at –20 °C. Slides of these specimens obtained with cryosection techniques were compared with MR images for evaluation of the damage to different parts of the discs. A total of 20 fractures were observed on cryosections. In 12 of the discs adjacent to fractured vertebral bodies, macroscopic damage was seen on the sections. These were all detected on the corresponding MR images. The study showed that MRI is able to detect acute, macroscopic injury to the intervertebral disc. It is therefore justified to use MR for the study of acute disc damage associated with thoracolumbar fractures. Received: 4 August 1998 Revised: 12 January 1999 Accepted: 27 January 1999     

Instrumented measurement of in vivo anterior-posterior translation in the canine knee to assess anterior cruciate integrity.

This study was designed to objectively quantify in vivo anterior-posterior canine knee translation relative to anterior cruciate ligament (ACL) integrity. Tibial translation was determined in one knee of 43 crossbreed hounds from radiographs performed while a set anterior and then posterior force was applied to the tibia using a custom designed device. The total (TTT), anterior (ATT), and posterior (PTT) tibial translation were measured (absolute) and normalized to the width of the tibia (normalized). Absolute and normalized TTT was significantly greater in ruptured ACL knees than in partially disrupted (PD) ACL knees, which were significantly greater than in intact ACL knees. ATT and PTT was significantly greater in ruptured ACL knees than in PD or intact ACL knees, which were not significantly different. The sensitivity and specificity of normalized TTT to distinguish knees with intact from PD ACLs were both 100%. Normalized TTT to distinguish knees with PD from ruptured ACLs had a sensitivity and specificity of 100% and 92%, respectively. Intra- and inter-observer intra-class correlation coefficients were 0.84 or higher for all translations. This precise non-invasive technique to assess canine knee translational stability and ACL integrity permits repetitive, objective measurements for diagnostic use and to assess therapeutic intervention efficacy.     

Normal development of the knee angle in healthy Indian children: a clinical study of 215 children

Purpose  

Physicians should be aware of the physiological variations of the knee angle in the local population to avoid unnecessary intervention in normal children. The normal development of the knee angle in children has been studied in various ethnic groups. However, there is a scarcity of such literature for Indian children.     

Triceps-sparing versus olecranon osteotomy for ORIF: analysis of 67 cases of intercondylar fractures of the distal humerus

The purpose of this study was to compare the triceps-sparing approach with olecranon osteotomy regarding their effects on the functional outcomes of intercondylar fractures of the distal humerus managed with open reduction and internal fixation (ORIF), by reviewing 67 cases of intercondylar distal humerus fractures surgically managed with either of the approaches during 2001-2009. The medical records and radiographs of 30 male and 37 female patients, with a mean age of 44.5 years (range, 16-77) and a mean follow-up time of 34.3 months (range, 6-89), were retrospectively reviewed. Flexion, extension, arc of flexion/extension, pronation, supination, arc of pronation/supination and the Mayo Elbow Performance Score (MEPS) were used to assess the functional outcomes of intercondylar distal humerus fractures treated with ORIF through the triceps-sparing approach or olecranon osteotomy. According to the AO Foundation (AO) classification, there were 10 cases of C1, 28 cases of C2 and 29 cases of C3 fractures. At the time of review, all fractures had united. Although there was no overall statistically significant difference in the average flexion, extension, arc of flexion/extension, pronation, supination and arc of pronation/supination between the triceps-sparing group (n = 34) and the olecranon osteotomy group (n = 33), patients above 60 years of age tended to have more extension loss (mean 22.9°, range 0-55°) after ORIF via the triceps-sparing approach, compared with any other surgical approach/age combination group. In the triceps-sparing group, although only 37.5% of patients over the age of 60 years obtained excellent/good MEPS, the rate increased to 100% in patients aged less than 40 years of age (P < 0.05). By contrast, the rate of excellent/good MEPS remained above 80% in all age groups of patients treated with ORIF via olecranon osteotomy. In conclusion, ORIF via the triceps-sparing approach confers inferior functional outcomes for intercondylar distal humerus fractures in patients over the age of 60 years, for whom the olecranon osteotomy approach may be a better choice. However, for patients less than 60 years of age, especially those less than 40 years of age, either approach confers satisfactory outcomes.     

Platelet‐rich plasma alone is not sufficient to enhance suture repair of the ACL in skeletally immature animals: An in vivo study

In this study, we hypothesize that supplementation of suture repair of the anterior cruciate ligament (ACL) with platelet‐rich plasma (PRP) will improve the biomechanics of the repair. Six 30‐kg pigs underwent bilateral suture repair of the ACL. One side was treated with suture repair alone, while the contralateral side was treated with suture repair augmented with PRP. After 14 weeks in vivo, anterior–posterior (AP) knee laxity and the tensile properties of the repaired ligament were measured. The addition of PRP to the suture repairs did not improve AP knee laxity at 30° (p = 0.73) or 60° (p = 0.65). It also did not improve the maximum tensile load (p = 0.64) or linear stiffness (p = 0.42) of the ACL repairs after 14 weeks in vivo. The model had 80% power to detect a 30% improvement of biomechanical properties with PRP; thus, we are confident that a clinically meaningful effect as a result of adding PRP is unlikely. Use of PRP alone to supplement suture repair of the ACL is ineffective in this animal model. Published by Wiley Periodicals, Inc. J Orthop Res 27: 639–645, 2009     

Evaluation of a method to map tibiofemoral contact points in the normal knee using MRI.

A technique using magnetic resonance imaging (MRI) is proposed for analysis of knee motion that is practical in the clinical situation. T1 weighted fast spin echo (FSE) and spoiled gradient echo (GE) sequences were compared to image both knees at 15 degrees intervals from 0 degrees to 90 degrees flexion, while unloaded and loaded. The medial and lateral tibiofemoral contact points were mapped reliably using both FSE sequences and GE sequences with intra-class correlation((2,1)) of 0.96 (CI 99%=0.94-0.97) and 0.94 (CI 99%=0.91-0.97), respectively. Results were consistent with the current literature on knee motion: the medial and lateral tibiofemoral contact pathways were different (F(1,80) = 253.9, p < 0.0001) reflecting the longitudinal rotation of the knee, the loaded and unloaded knees were not different in the healthy knee (F(1,80) = 0.007, p = 0.935), and the left and right knee were consistent for each individual (F(1,80) = 0.005, p = 0.943). Therefore, right to left differences may be attributed to pathology. MRI analysis of knee kinematics as described by this technique of tibiofemoral contact point mapping provides a robust and reliable method of recording the tibiofemoral contact pattern of the knee.