Lateral ligament injuries of the knee

Between 1982 and 1994 28 patients were treated for acute lateral knee ligament injuries; 25 patients, with a median age of 25.5 (range 16–75) years at injury, appeared for follow-up. Seven patients had isolated injury of the lateral collateral ligament/capsular structures, the remaining 19 patients had concomitant ligament injuries in the knee. Eight patients were treated conservatively, 1 with plaster immobilization and 7 with early mobilization. Eighteen patients underwent surgery, 17 of these within 3 weeks of injury. Repair/reconstruction of the cruciate ligaments was done at the same time as the lateral collateral ligament repair in 10 patients. At follow-up after a median of 7.5 years (range 6 months to 13 years), 11 had no varus instability, 7 had 1+, 5 had 2+, and 2 patients had 3+ varus instability. All patients with a final result of 2+ or 3+ had combined ligament injuries. The surgically treated lateral collateral ligament injuries all had a primary instability of 2+ or more. These patients showed an improvement in varus instability from a mean of 2.83+ preoperatively to a mean of 1.17+ postoperatively. Two-thirds of the surgically treated patients were stable or had a 1+ instability at follow-up. One conservatively treated patient with a 2+varus instability and 1 with 1+ showed no improvement. Five conservatively treated patients with initial varus instability of 1+ were stable at follow-up. One patient with a 1+ varus instability had anterior cruciate ligament (ACL) rupture. He had a primary ACL reconstruction without lateral repair. He had no varus instability at follow-up. Our study supports the notion that operation performed at an early stage in fresh injuries with a varus instability of 2+ or more gives improved stability as a final result. Conservative treatment may not be expected to give an improved stability, but is sufficient in mild varus instability (1+) without additional cruciate ligament injuries. Received: 22 January 1997 Accepted: 20 June 1997     

Posterolateral supporting structures of the knee: findings on anatomic dissection, anatomic slices and MR images

In this article we study the ligaments and tendons of the posterolateral corner of the knee by anatomic dissection, MR-anatomic correlation, and MR imaging. The posterolateral aspect of two fresh cadaveric knee specimens was dissected. The MR-anatomic correlation was performed in three other specimens. The MR images of 122 patients were reviewed and assessed for the visualization of different posterolateral structures. Anatomic dissection and MR-anatomic correlation demonstrated the lateral collateral, fabellofibular, and arcuate ligaments, as well as the biceps and popliteus tendons. On MR images of patients the lateral collateral ligament was depicted in all cases. The fabellofibular, arcuate, and popliteofibular ligaments were visualized in 33, 25, and 38% of patients, respectively. Magnetic resonance imaging allows a detailed appreciation of the posterolateral corner of the knee.     

MRI对膝关节前交叉韧带损伤的诊断

目的 研究正常和损伤的膝关节前交叉韧带的MRI表现。方法 回顾性分析16例前交叉韧带正常和19例前交叉韧带损伤的MRI表现。结果 正常的前交叉韧带在矢状位上呈一连续笔直的T1WI、T2WI均为低信号的带状影。前交叉韧带损伤的MRI表现为韧带连续性中断4例（韧带内形成假瘤1例）,韧带外形不规则4例、韧带水平走向2例和韧带信号增高9例。结论 MRI是一种首选的诊断前交叉韧带损伤的非创伤性检查方法。     

A biomechanical analysis of two reconstructive approaches to the posterolateral corner of the knee

The objective of this study was to evaluate the effects of the biceps femoris tenodesis and popliteofibular ligament reconstruction on knee biomechanics. Ten human cadaveric knees were tested in the intact, posterolateral corner (PLC)-deficient, and PLC-reconstructed conditions using a robotic/universal force moment sensor testing system. The knees were subjected to: (1) a 134 N posterior tibial load, and (2) a 10 Nm external tibial torque applied to the tibia at full extension, 30° and 90° of flexion. External tibial rotation of the intact knee ranged from 18.3±4.6° at full extension to 27.9±4.6° at 30° under the 10 Nm external tibial torque. These values increased after sectioning the PLC by 2.8°–7.5° at 30° and 90° respectively. After the popliteofibular ligament reconstruction, external tibial rotation values were not significantly different from those for the intact knee at any angle tested, while values following the biceps tenodesis were as much as 5.7° greater than the intact knee. Under the 134 N posterior tibial load, there were minimal decreases in posterior tibial translation of up to 0.9 mm with the biceps tenodesis and up to 1.6 mm with the popliteofibular ligament reconstruction compared to the intact knee. The in situ forces in the biceps tenodesis were not significantly different than the intact PLC at full extension or 30°, while the in situ forces in the popliteofibular graft were not significantly different at any flexion angle. Our data suggests that by restoring external tibial rotation the popliteofibular ligament reconstruction more closely reproduces the primary function of the PLC as compared to the biceps tenodesis.     

MRI in assessment of sports related knee injuries

Purpose

To investigate the accuracy of MRI in assessment of sports related knee injuries.

Materials and methods

From August 2012 to March 2013 thirty patients referred for sports related knee pain have been included in this study. Patients were subjected to a dedicated MR knee study and correlated knee arthroscopy and surgery.

Results

The study included thirty patients complaining of sports related knee pain, only 5 patients (16.6%) were with normal MRI findings and 25 patients (83.4%) were with abnormal MRI findings. Among the 25 patients who had injuries of their knees, 15 patients (60%) had ACL injuries, 2 patients (8%) had PCL injuries, 10 patients (40%) had meniscal injuries, 8 patients (32%) had collateral ligament injuries, 5 patients (20%) had bone injuries and 2 patients (8%) had muscular injuries. Only 7 patients (28%) were represented with isolated injury and 18 patients (72%) were represented with combined injuries. In correlation with arthroscopies and surgeries, morphological analysis was true-positive in 23 (92%) patients of the 25 injured patients, and true-negative in 3 (60%) patients of the 5 normal patients. Morphological analysis revealed overall 92% sensitivity and 60% specificity. Regarding the 15 patients who had ACL injuries, 13 patients (86.6%) were true-positive and 8 patients (80%) of the 10 patients who had meniscal injuries were true-positive.

Conclusion

MRI represents the optimal imaging tool in the evaluation of the sports related knee injuries, which has been shown to be an accurate and non invasive method of diagnosing ligament, meniscal, cartilage and muscular knee injuries.     

Imaging of the collateral ligament injuries of the knee

The role of routine and advanced imaging techniques after suspected injury to the collateral ligaments of the knee is to augment the findings on physical examination. Although radiographs may disclose avulsion injuries, the limited soft tissue contrast does not permit accurate assessment of the collateral ligaments and associated soft tissue structures. Because of its superior soft tissue contrast and multiplanar capabilities, magnetic resonance (MR) imaging has largely replaced conventional imaging techniques. Using high-contrast pulse sequences, MR imaging permits localization of the site of ligamentous trauma, as well as associated soft tissue injury, including meniscal tears, cruciate ligament tears, and injury to the structures of the posterolateral corner. Although secondary signs of ligamentous injury, including adjacent soft tissue edema and bony contusions, may be helpful in localizing the site of injury, the most important criteria remains direct visualization of the ligament, with focal discontinuity. Using such criteria, accurate preoperative assessment of the injured extremity may be made, thereby aiding in the clinical management of the patient.     

Histological and ultrastructural evaluation of Leeds-Keio ligament 20 years after implant: a case report

We were capable of undertaking a histological and ultrastructural evaluation of an intact Leeds-Keio ligament implanted 20 years ago to assess the neoligamentization process inside this artificial ligament. The histological evaluation disclosed a collagen fibrils orientation very close to the structure of a normal anterior cruciate ligament (ACL) where the collagen fibres are multidirectional [Strocchi et al. in J Anat 180(3):515–519, 1992]. On the other hand we found an unimodal distribution of collagen fibrils in the reconstructed ACL. This suggests that even at long-term follow-up stress exerts a variable influence. The multidirectional arrangement of collagen fibres resembles a normal ACL, but the unimodal distribution of fibrils is quite different from those seen in normal tendon and ligaments which tend to have a bimodal peak [Decker et al. in J Submicrosc Cytol Pathol 23:9–21, 1991; Strocchi et al. in J Anat 180(3):515–519, 1992]. Studies based on biopsy suffer from the potential weakness that the specimen may not have been representative of the entire prosthesis. Further long-term studies, possibly with the entire prosthesis and not only a biopsy, would highlight the behaviour and remodelling of this artificial ligament in greater detail and could be important for the development of future generations of artificial ligaments or tissue engineering ACL reconstruction.     

Kinetic changes associated with extended knee landings following anterior cruciate ligament reconstruction in females

ObjectivesTo determine the relationship between knee flexion excursion symmetry and lower extremity kinematics, kinetics, and muscle, joint, and ligament forces in females 1–3 years after ACL reconstruction.DesignCross-sectional.SettingLaboratory.ParticipantsTwenty-one, college-aged females.Main outcome measuresLower extremity kinetics and kinematics, including estimated muscle, tibiofemoral, and ligament forces were assessed using 3D motion analysis and a musculoskeletal modeling approach. Participants demonstrating greater than 10% asymmetry in knee flexion excursion were classified as landing with an “extended knee”. Group and between-limb differences were compared.ResultsTen participants were classified as landing with an “extended knee” on the involved limb, while eleven exhibited a symmetric landing pattern. Participants landing with an “extended knee” demonstrated reduced knee extension moment and quadriceps force in the involved limb (p < 0.05).ConclusionsThese findings indicate that an “extended knee” landing pattern was associated with reduced knee extension moment and quadriceps muscle force in females 1–3 years after ACL reconstruction. This may represent an altered strategy that clinicians may choose to identify and address during rehabilitation.     

Translation and testing of measurement properties of the Swedish version of the IKDC subjective knee form

To translate to Swedish language and cross‐culturally adapt the IKDC‐SKF and to test the measurement properties of the Swedish version of IKDC‐SKF in ACL‐injured patients undergoing reconstruction surgery.The translation and cross‐cultural adaption was performed according to guidelines. Seventy‐six patients with an ACL injury filled out the IKDC‐SKF and other questionnaires before ACL reconstruction and at 4, 6, and 12 months after surgery. A total of 203 patients from the Swedish ACL Registry participated at 8 months post‐operative. Measurement properties were tested according to the COnsensus‐based Standards for the selection of health Measurement INstruments (COSMIN) guidelines.The Swedish IKDC‐SKF had high internal consistency (Cronbach′s alpha=0.90) and test‐retest reliability (ICC_2,1=0.92, CI 95%: 0.81‐0.97, P<.001). A single factor solution accounted for 46.1% of the variance in IKDC‐SKF scores. Criterion validity was moderate to high. All ten predefined hypotheses for hypothesis testing were confirmed. The six hypotheses for responsiveness testing were confirmed. The effect size was 1.8, the standardized response mean was 1.9, the and minimal clinically important difference was 13.9 points.The Swedish version of the IKDC‐SKF had good measurement properties and can be recommended for use in a population of ACL‐deficient patients undergoing ACL reconstruction.     

Newer trends in imaging bony injuries of the knee

With newer advances in imaging technology, evaluation of the acutely traumatized knee has evolved. After the initial plain radiographic examination, it has become standard practice to use magnetic resonance imaging, especially when internal knee derangement is suspected. This review discusses imaging of common bony knee injuries.     

膝关节后外侧结构的解剖与MRI研究

目的 改进膝关节后外侧结构MRI定位方法，提高后外侧结构损伤的诊断准确率。方法 解剖膝关节标本，辨认后外侧各结构起止点及走行，明确它们之间的解剖关系。以注水的输液器缝合标记各结构进行MRI扫描，测量各结构在矢状面和冠状面上与腓骨颈长轴之间的夹角。按照这些角度定位扫描正常膝关节，观察各结构在MRI中完整显示的情况。结果 （1）测得矢状面上腓侧副韧带和胴肌腱关节囊内部分与腓骨颈长轴的夹角分别为（11．5±1.7）°和（39．5±6，4）°冠状面上胴肌腱关节囊外部分和胴腓韧带与腓骨颈长轴夹角为（39.5±3．9）°和（31．9±3．9）°。（2）腓侧副韧带在11°后斜冠状位1个层面上完整显示占90％，胴肌腱关节囊内部分在40°后斜冠状位1个层面上完整显示占80％，胭肌腱关节囊外部分在内斜40°矢状位1个层面上完整显示占90％，胭腓韧带在外斜30°矢状位1个层面上完整显示占90％。此外，胴腓韧带在11°后斜冠状位1个层面上完整显示的占75％，股二头肌腱和髂胫束在常规冠状面均能够很好显示.结论 选择完整显示腓骨茎突和腓骨颈的冠状面和矢状面为基准面，按照后外侧各结构与腓骨颈长轴所呈角度进行定位，层厚2mm的MR扫描能很好地显示膝关节后外侧解剖结构。     

Synovialisation of the torn anterior cruciate ligament of the knee: comparison between magnetic resonance and arthroscopy

The aim of this study was to assess the accuracy of MR in the diagnosis of synovialisation of the anterior cruciate ligament (ACL) compared with arthroscopy. One hundred and forty-nine patients were examined with MR imaging and arthroscopy of the knee. The MR sign used to consider a synovialised ACL consisted of hypointense fibrillar tracts, disrupted and wavily, in its expected course. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), comparison of proportions (McNemar test) and Kappa values for agreement between MR imaging and arthroscopy were calculated. Of the 133 (89.3 %) ligaments without synovialisation at arthroscopy, 130 accorded with the MR results. Of the 16 (10.7 %) synovialised ligaments, 13 accorded with the MR results. Three false-positive and three false-negative MR diagnoses were identified. The agreement between both techniques was excellent (Kappa = 0.79; p = 0.000), without differences (McNemar test; p = 1). Sensitivity was 0.81, specificity 0.98, PPV 0.98 and NPV 0.81. Magnetic resonance imaging is highly reliability for synovialisation diagnosis. The imaging sign used to diagnose synovialised ACL (hypointense comma-like tracts in its expected course) is reliable. As this reparative process can simulate an intact ligament, knowledge of this sign is important in diagnosing synovialisation of ACL tears so as not to confuse it with normal ACL. Received: 17 June 1998; Accepted: 6 August 1998     

Instrumented measurements of knee laxity: KT-1000 versus navigation

The KT-1000 is widely accepted as a tool for the instrumented measurement of the antero-posterior (AP) tibial translation. The aim of this study is to compare the data obtained with the KT-1000 in ACL deficient knees with the data obtained using a navigation system during “in vivo” ACL reconstruction procedures and to validate the accuracy of the KT-1000. An ACL reconstruction was performed using computer aided surgical navigation (Orthopilot, B-Braun, Aesculap, Tuttlingen, Germany) in 30 patients. AP laxity measurements were obtained for all patients using KT-1000 arthrometer (in a conscious state and under general anaesthesia) and during surgery using the navigation system, always at 30° of knee flexion. The mean AP translation was 14 ± 4 and 15.6 ± 3.8 mm using the KT-1000 in conscious and under general anaesthesia, respectively (P = 0.02) and 16.1 ± 3.7 mm using navigation. Measurements obtained with the KT-1000 under general anaesthesia were no different from those obtained “in vivo” with the navigation system (P = 0.37). In conclusion this study validates the accuracy of the KT-1000 to exactly calculate AP translation of the tibia, in comparison with the more accurate measurements obtained using a navigation system.     

MR imaging of patellar retinacular ligament injuries

Seventeen patients with patellar retinacular ligament injuries were evaluated with magnetic resonance (MR) imaging. MR findings were correlated with clinical, surgical, and arthroscopic findings. The injuries involved the medial retinacular ligament in 16 of 17 patients and the medial and lateral retinacular ligament in one patient. Nine of 17 patients showed MR evidence of a patellar dislocation. In these patients, a triad of findings that included focal impaction injuries involving the lateral femoral condyle, osteochondral injuries of the medial patellar facet, and injuries of the medial retinacular ligament were seen. Seven of the nine patients with patellar dislocation injuries had frank osteochondral injuries. The injured retinaculum had an indistinct, irregular appearance associated with edema and hemorrhage. The patellar dislocations were clinically unsuspected in the initial evaluation of eight of these nine patients. In eight of 17 patients, the mechanism of injury was a patellar tendon tear (n = 1) or valgus hyperextension (n = 7). In the seven patients with hyperextension injuries, three had associated meniscal and cruciate ligament tears. MR imaging can help define patellar retinacular and associated osteochondral injuries, which may be clinically useful information.     

膝关节韧带损伤的MRI诊断

目的:探讨膝关节韧带损伤的MRI表现及诊断价值。方法:36例临床怀疑膝关节损伤的患者于关节镜及手术前行MRI检查,以关节镜结果作为金标准,前瞻性分析膝关节韧带损伤的MRI表现及诊断价值。结果:关节镜证实前交叉韧带损伤21例,其中完全撕裂15例,部分撕裂6例,后交叉韧带损伤12例,正常患者15例。MRI诊断前交叉韧带损伤的敏感度为95.2%,特异度为80%,准确度为88.9%;诊断后交叉韧带损伤的敏感度为100%,特异度为95.8%,准确度为97.2%。结论:MR1是诊断膝关节韧带损伤的理想检查方法,具有较高的临床应用价值。     

Surgical treatment of acl-pcl-medial side-lateral-side injuries of the knee

The multiple-ligament-injured knee is a complex problem in orthopaedic surgery. Most dislocated knees involve tears of the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), and at least one collateral ligament complex. Careful assessment of the extremity vascular status is essential because of the possibility of arterial and/or venous compromise. These complex injuries require a systematic approach to evaluation and treatment. Physical examination and imaging studies enable the surgeon to make a correct diagnosis and to formulate a treatment plan. Arthroscopically assisted combined ACL/PCL reconstruction is a reproducible procedure. Knee stability is improved postoperatively when evaluated by using knee-ligament rating scales, arthrometer testing, and stress radiographic analysis. Acute medial collateral ligament tears when combined with ACL/PCL tears may, in certain cases, be treated with bracing. Posterolateral corner injuries combined with ACL/PCL tears are best treated with primary repair, as indicated, combined with reconstruction by using a post of strong autograft (split biceps tendon, biceps tendon, semitendinosus) or allograft (Achilles tendon, bone—patellar tendon—bone) tissue. Surgical timing depends on the ligaments injured, the vascular status of the extremity, reduction stability, and the overall health of the patient. We prefer the use of allograft tissue for reconstruction in these cases because of the strength of these large grafts and the absence of donor-site morbidity.     

Surgical treatment of ACL/PCL/ medial-side knee injuries

The medial cruciate ligament (MCL), anterior cruciate ligament (ACL), and posterior oblique ligament (POL) frequently are injured by a combination of valgus and external rotation forces. Grade I or II MCL injuries alone or in combination with ACL or posterior cruciate ligament (PCL) injuries are treated nonoperatively, with cruciate ligament reconstruction delayed 3 to 6 weeks. Treatment of acute grade III ACL/PCL medial knee injuries remains controversial. Recommendations have included nonoperative treatment of the MCL and reconstruction of the ACL and PCL, acute reconstruction of the MCL and nonoperative treatment of the ACL, and treatment of all grade III injuries with acute repair. For chronic ACL/PCL/medial knee injuries, magnetic resonance imaging and examination under anesthesia are followed by endoscopic ACL/PCL reconstruction. Severe valgus laxity usually requires tightening of the MCL in addition to the posterior capsule, the posterior oblique area of the posteromedial capsule, and the midmedial capsular ligament. Thorough preoperative planning is essential to determine what procedures will be necessary for each patient.     

Development of a simple device for measurement of rotational knee laxity

The goal of this study was to develop a new device for the measurement of rotational knee laxity and to measure intra-observer and inter-observer reliability in a cadaveric study. An array of established tools was utilized to design the device with a basis that consists of an Aircast Foam Walker™ boot. A load cell was attached to the boot with a handle bar for application of moments about the knee. An electromagnetic tracking system was used to record the motion of the tibia with respect to the femur. The total arc of motion ranged from 23° at full extension to 46° at 90° of knee flexion. The intra-tester ICCs ranged from 0.94 to 0.99. The ICC for inter-tester reliability ranged from 0.95 to 0.99. In summary, the new device for measurement of rotational knee laxity is simple, reliable, and can be used in a non-invasive fashion in the office or surgical suite document clinical outcome in terms of rotational knee laxity.     

Accuracy of double-contrast arthrography and arthroscopy of the knee joint

Only in the diagnosis of medial meniscal lesions is double contrast arthrography superior to arthroscopy, provided that arthroscopy is carried out only from the anterolateral side (94% against 81% positive correlations). The rates in diagnosing lateral meniscal lesions are respectively 90% and 94.5%, in patellar chondropathy 55% and 99.5% respectively, and in diagnosing cruciate ligament lesions 69% and 97% respectively.