Posterior Knee Joint Research Articles

Diagnosis and treatment of crouch gait in children with cerebral palsy. Report from the 4th Edition of the Transatlantic Orthopedic Surgery Webinar 2022

Introduction. The fourth edition of the Transatlantic Orthopedic Surgery Webinar 2022 took place on December 12th, 2022. The main theme of the webinar was the treatment of crouch gait in children with cerebral palsy (CP). Speakers from Australia, Canada, China, Germany, India, Poland, Spain, Sweden, Turkey, the United Kingdom, and the United States participated. Results. The first general session presented the biomechanics of crouch gait, the function of the hip and knee muscles in children with CP, the principles of prevention and treatment of crouch gait in spastic diplegia, and the natural course and treatment outcomes of CP in adults. The surgical sessions comprehensively presented the surgical techniques for treating crouch gait: percutaneous myofasciotomy in the posterior knee joint, straightening osteotomy of the distal femur in hemiplegia, asymmetric and symmetric diplegia, techniques for shortening and plastically reconstructing the patellar ligament, anterior hemiepiphysiodesis of the distal femur, and transfer of the hamstring muscles to the rectus femoris muscle. The second general session presented postoperative standing and walking rehabilitation protocols and evaluation of treatment outcomes (pain, fatigue, ambulatory activity, motor function, and quality of life). Summary. The most important conclusions from the event were: do not lengthen the Achilles tendon in zone III in crouch gait; laboratory gait analysis is necessary before lengthening the hamstring muscles; hemiepiphysiodesis of the distal femur can be performed when the predicted growth period is less than two years; distal femur osteotomy should be considered during adolescence for knee flexion contracture of 10-40 degrees; treatment possibilities of tendon transfers and myofasciotomies should be remembered, especially in younger patients. The webinar attracted an audience of approximately 1,600 people from 672 centers located in 57 countries. Most participants came from Poland, the United Kingdom, the United States, Norway, Sweden, and India.

Intraneural Ganglion Cyst of the Tibial Nerve Originating from a Posterior Knee Joint Branch. Case Report on the Use of High-Resolution Volumetric Ultrasound and Magnetic Resonance Neurography.

We report a case of an intraneural ganglion cyst (INGC) of the tibial nerve at the posterior knee joint, diagnosed with ultrasound, 3D ultrasound, and MR neurography.

Distance to the Neurovascular Bundle for Iliotibial Band Graft Passage During Anterior Cruciate Ligament Reconstruction: A Pediatric Cadaveric Study.

Background:The Micheli technique for anterior cruciate ligament (ACL) reconstruction (ACLR) has proven to be a reliable method with a minimal risk for growth disturbance among skeletally immature patients.Purposes:To evaluate the Micheli technique of iliotibial band (ITB) graft passage for ACLR using cadaveric knee models and to measure the distance between the surgical instrument tip and the neurovascular bundle in the posterior knee joint: specifically, the peroneal nerve, tibial nerve, and popliteal artery.Study Design:Descriptive laboratory study.Methods:Gross dissection was performed on 17 pediatric cadaveric knees (12 male and 5 female) aged between 4 and 12 years. To simulate ITB graft passage, we passed a curved-tip hemostat clamp through the posterior capsule, with the knee flexed from 90° to 100°. Next, clinical photographs were taken, and digital imaging software was used to measure the distance in centimeters from the clamp tip to each respective neurovascular structure.Results:The mean distances from the clamp tip to the tibial nerve, popliteal artery, and peroneal nerve were 0.875 cm (range, 0.468-1.737 cm), 0.968 cm (range, 0.312-1.819 cm), and 1.149 cm (range, 0.202-2.409 cm), respectively. Mean values were further calculated for age groups of ≤8, 9-10, and 11-12 years. The mean distance from the clamp tip to the peroneal nerve was 1.400 cm larger for 11- to 12-year-old specimens than for ≤8-year-old specimens (95% CI, 0.6-2.2 cm; P = .005).Conclusion:The neurovascular structures in the posterior knee were in close proximity to the path of graft passage, with distances <1 cm in many specimens in this study. When passing the graft through the knee for an over-the-top position, surgeons should consider these small distances between the path of graft passage and critical neurovascular structures.Clinical Relevance:As the incidence of ACL tears is continuously increasing within the pediatric population, there are a larger number of ACLR procedures being performed. Although neurovascular injuries during ACLR are rare, this study clarifies the close proximity of neurovascular structures during ITB graft passage using the Micheli technique of ACLR.

Gait Classification and Physical Function Characteristics in Maintenance Hemodialysis Patients

Only walking velocity has been reported as a performance measure of gait in hemodialysis patients, and no kinematic or kinetic analysis has been reported. We evaluated basic information, physical function, aging, dialysis-related complications, and gait in 23 outpatients (≥60 years old) who could walk independently. Hierarchical cluster analysis was performed using joint angles, joint moments, and gait parameters during gait. The gait of hemodialysis patients was classified into two clusters: Cluster 1 and Cluster 2. Cluster 1 gait showed a longer hemodialysis duration, higher dialysis amyloidosis severity, knee joint pain, lower ankle plantarflexion weakness, and lower extremity joint dysfunction than Cluster 2. The gait of Cluster 1 patients consisted of flexion of the knee joint, ankle joint, and trunk, and excessive knee joint flexion was observed in the stance phase to escape posterior knee joint pain. Cluster 1 patients were also unable to kick out sufficiently, and their walking rate and walking velocity were decreased. Cluster 2 patients had a shorter hemodialysis duration than Cluster 1. External forces exerted on the knee joint in the hyperextension direction during gait could cause pain and inflammation of the posterior knee joint.

Distance to Neurovascular Bundle During Iliotibial Band Acl Graft Passage: A Cadaveric Study

Background:For patients with significant growth remaining, the Micheli-Kocher (iliotibial band) ACL reconstruction technique has proven to be a reliable procedure with minimal risk for growth disturbance. Recent cadaveric studies have demonstrated that graft passage over the top of the femur may bring the graft and instrument close to the critical neurovascular structures.Purpose:The purpose of this study was to evaluate the over-the-top graft passage technique using pediatric cadaveric knees, and measure the distance between instruments and the peroneal nerve, tibial nerve, popliteal artery.Methods:Seventeen skeletally immature cadaveric knees between the ages of 4 and 12 years old were dissected and prepared for visualization of iliotibial band graft passage procedure. A curved hemostat clamp was used, creating a path through the posterior capsule. To avoid neurovascular injury, the tip of the instrument was kept close to the posterior and lateral cortex of the femur. Once the clamp was safely positioned in the posterior knee joint, photographs were taken. Digital imaging software was used to measure the distance in centimeters from clamp tip to peroneal nerve laterally, and the popliteal artery and tibial nerve medially for all specimens, FIGURE 1. Distances were averaged and stratified to assess differences in age, FIGURE 2.Results:The average distances from clamp to neurovascular bundle were 0.875cm (range: 0.468-1.737cm), 0.968cm (range: 0.312-1.819cm), and 1.149cm (range: 0.202-2.409cm) for tibial nerve, popliteal artery and peroneal nerve, respectfully. Means were further calculated for age groups ≤8, 9-10, and 11-12 years old.Conclusion:Iliotibial band graft ACL reconstruction is one of the best options in the skeletally immature, as it has the lowest risk of growth plate complications and growth arrest. The neurovascular structures are very close to the path for over-the-top graft clamp placement with distances <1 cm in many subjects. The current study provides detailed measurements of instrument proximity to the neurovascular bundle in the posterior compartment of the knee. This knowledge is important to help surgeons who perform the Micheli-Kocher pediatric ACL reconstruction avoid damage to the nerves and vessels in this region. Careful instrument and graft passage, with awareness of proximity to critical structures, are important to reduce the risk of neurovascular injury.Figure 1.Measurements (cm) from clamp tip to neurovascular bundle in right knee model.Figure 2.Average distance from surgical instrument to neurovascular bundle are identified with respect to age.

Modified posterior approach of the knee in patients with diffuse pigmented Villonodular synovitis: case series of a single Institution’s experience

BackgroundDiffuse pigmented villonodular synovitis (DPVNS) is a challenging tumor-like disorder that mainly occurs in the anterior aspect of the knee joint. The growth may sometimes extend to the posterior knee joint. Surgical excision is the mainstream treatment for DPVNS, and the posterior approach of tumor excision is adopted when the dominant tumor shows posterior extension. However, the optimal surgical approach over the posterior knee remains unknown.MethodsPatients with DPVNS of the knee joint who received the posterior approach of synovectomy from 1995 to 2019 were retrospectively reviewed to describe the modified separate posterior (SP) approaches, and evaluate the treatment outcomes in a case series of DPVNS knees. The results of the SP approach was also compared with those of traditional direct posterior (DP) approach. Postoperative functional outcomes were evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) standardized questionnaire and clinician-completed Musculoskeletal Tumor Society (MSTS) functional rating system at outpatient department.ResultsA total of 20 DPVNS knees were included. Thirteen patients who received SP approaches were included in the SP group, while seven patients who received the DP approach were included in the DP group. The median follow-up times were 5.7 years (IQR, 2-8.8) in the SP group and 3 years (IQR, 2-5.3) in the DP group. Both groups showed satisfactory safety. The SP group presented higher postoperative mean WOMAC (91.23 ± 7.20) and mean MSTS (24.23 ± 2.68) than the DP group (mean WOMAC: 76.00 ± 16.57; mean MSTS: 22.43 ± 4.69). The Wilcoxon signed-rank test was use to compare preoperative and postoperative range of motion (ROM) for each group. The significant difference in SP group (p = 0.004) was found while p = 0.131 in DP group.ConclusionsThe SP approach provides an effective approach with satisfactory outcomes for the surgical treatment of DPVNS knees.

Genicular Nerve Radiofrequency Ablation and Dual Subsartorial Block for Chronic Knee Pain Post Total Knee Replacement: A Case Report

Introduction. Chronic pain defines as pain persisting for three months or longer, chronic post-surgical pain can affect all dimensions of health-related quality of life, and is associated with functional limitations. treatment of chronic pain after total knee replacement is challenging, and evaluation of combined treatments and individually targeted treatments matched to patient characteristic. Genicular nerve block radiofrequency ablation is a safe and effective therapeutic procedure for pain associated with chronic pain due to knee osteoarthritis, and the evolution of newer regional analgesia techniques aids in reducing postoperative pain Dual Subsartorial Block (DSB) as a procedure specific, post total knee replacemet. historically there has been a reliance on using a pain-spesific assessment tools Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)&#x0D; Case Presentation. A 55-year old woman admitted she had pain on bilateral knee, the knee pain had affected her daily living, she was diagnosed with chronic knee pain post TKR because of osteoarthritis genu bilateral, the patient was planning genicular nerve radiofrequency ablation and dual subsartorial block, from the examination we found that numeric rating scale was 6 (moderate pain) with WOMAC score 76, before the procedure the patients are examined through radiology for any deformity in the knee. The genicular nerve radiofrequency ablation under ultrasound guidance on bonylandmark, resulting anesthesia of the anterior compartment of the knee, and dual subsartorial block that cover almost all the innervations of pain generating component of the anterior and posterior knee joint involved in TKR surgery. After the procedure we reevaluated the pain score using NRS was 2 (mild pain), and with WOMAC Score 19.&#x0D; Conclusion. Treatment of chronic pain post total knee replacemet was challenging, targeted treatment may ameliorate the pain and prevent long term disability.&#x0D;

The Dose-Response Effect of the Mast Cell Stabilizer Ketotifen Fumarate on Posttraumatic Joint Contracture: An in Vivo Study in a Rabbit Model.

Background:Posttraumatic joint contracture is a debilitating complication following an acute fracture or intra-articular injury that can lead to loss of motion and an inability to complete activities of daily living. In prior studies using an established in vivo model, we found that ketotifen fumarate (KF), a mast cell stabilizer, was associated with a significant reduction in the severity of posttraumatic joint contracture. Our primary research question in the current study was to determine whether a dose-response relationship exists between KF and posttraumatic joint contracture reduction.Methods:A standardized operative method to create posttraumatic joint contracture in a knee was performed on skeletally mature New Zealand White rabbits. The animals were randomly assigned to 1 of 5 groups (n = 10 per group): a nonoperative control group, an operative control group, or 1 of 3 experimental KF groups (0.01 mg/kg [the KF 0.01 group], 0.1 mg/kg [KF 0.1], or 5.0 mg/kg [KF 5.0]). Flexion contractures were measured following 8 weeks of knee immobilization using a hydraulic material-testing machine. The posterior knee joint capsules were then harvested for quantification of myofibroblast and mast cell numbers with immunohistochemistry analysis.Results:Forty-five rabbits were used in the final analysis. Contracture severity was significantly reduced in the KF 0.1 group (p = 0.016) and the KF 5.0 group (p = 0.001) compared with the operative control group. When converted to a percent response, posttraumatic joint contracture reduction was 13%, 45%, and 63% for the KF 0.01, KF 0.1, and KF 5.0 groups, respectively. A half-maximal effective concentration (EC50) for KF of 0.22 mg/kg was established. There was also a decrease in myofibroblasts, mast cells, and substance P-containing nerve fiber counts with increasing doses of KF.Conclusions:Using a preclinical, rabbit in vivo model of posttraumatic joint contracture, increasing doses of KF were associated with decreasing biomechanical estimates of knee posttraumatic joint contracture as well as decreasing numbers of myofibroblasts, mast cells, and substance P-containing nerve fibers.Clinical Relevance:KF has been used safely in humans for more than 40 years and, to our knowledge, is the first and only agent ready to be potentially translated into an effective treatment for posttraumatic joint contracture.

Review of Knee Joint Innervation: Implications for Diagnostic Blocks and Radiofrequency Ablation.

To determine if commonly used knee radiofrequency ablation (RFA) techniques would be able to completely denervate the knee joint. A comprehensive search of the literature on knee joint innervation was conducted using the databases Medline, Embase, and PubMed from inception through February 1, 2019. Google Scholar was also searched. Data on the origin, number of articular branches, course, distribution, and frequency of each nerve innervating the knee joint were extracted from the included studies and compared in order to identify variations. Twelve studies of anterior knee joint innervation and six studies of posterior knee joint innervation were included. The anterior knee joint was innervated by 10 nerves and further subdivided into two parts (anteromedial and anterolateral) or four quadrants (superomedial, inferomedial, superolateral, and inferolateral) based on innervation patterns; the posterior knee joint was innervated by two or three nerves, most commonly via the popliteal plexus. There is a lack of precise, validated anatomic targets identifiable with fluoroscopy and ultrasound for knee diagnostic blocks and RFA. Only three of the 12 or potentially 13 nerves innervating the knee joint are targeted by commonly used knee RFA techniques. Commonly used knee RFA techniques would not be able to completely denervate the knee joint. It may not be necessary to capture all of the nerves, but only the nerves mediating a patient's pain. Further clinical studies are required to validate specific diagnostic blocks and evaluate clinical outcomes using rigorous diagnostic blocks and anatomically specific knee RFA techniques.

Effects of losartan and atorvastatin on the development of early posttraumatic joint stiffness in a rat model.

BackgroundAfter a trauma, exuberant tissue healing with fibrosis of the joint capsule can lead to posttraumatic joint stiffness (PTJS). Losartan and atorvastatin have both shown their antifibrotic effects in different organ systems.ObjectiveThe purpose of this study was the evaluation of the influence of losartan and atorvastatin on the early development of joint contracture. In addition to joint angles, the change in myofibroblast numbers and the distribution of bone sialoprotein (BSP) were assessed.Study design and methodsIn this randomized and blinded experimental study with 24 rats, losartan and atorvastatin were compared to a placebo. After an initial joint injury, rat knees were immobilized with a Kirschner wire. Rats received either losartan, atorvastatin or a placebo orally daily. After 14 days, joint angle measurements and histological assessments were performed.ResultsLosartan increased the length of the inferior joint capsule. Joint angle and other capsule length measurements did not reveal significant differences between both drugs and the placebo. At cellular level both losartan and atorvastatin reduced the total number of myofibroblasts (losartan: 191±77, atorvastatin: 98±58, placebo: 319±113 per counting field, p<0.01) and the percentage area of myofibroblasts (losartan: 2.8±1.8% [p<0.05], atorvastatin: 2.5±1.7% [p<0.01], vs control [6.4±4%], respectively). BSP was detectable in equivalent amounts in the joint capsules of all groups with only a trend toward a reduction of the BSP-stained area by atorvastatin.ConclusionBoth atorvastatin and losartan reduced the number of myofibroblasts in the posterior knee joint capsule of rat knees 2 weeks after trauma and losartan increased the length of the inferior joint capsule. However, these changes at the cellular level did not translate an increase in range of motion of the rats´ knee joints during early contracture development.

Evaluation of the iPACK block injectate spread: a cadaveric study

Background and objectivesUltrasound-guided infiltration of the interspace between the popliteal artery and capsule of the knee (iPACK) block, a new regional analgesic technique, is believed to relieve posterior knee pain,...

Atraumatic Calf Swelling In Recreational Cyclist

HISTORY: 51 year-old male presented with intermittent left calf pain and swelling for the past 2 months. The pain and swelling became constant the week preceding his presentation. He had no known injury but first noticed the pain after a spin class 2 months ago. The pain was worse with cycling, jogging, and swimming and at the end of the day. He had no knee pain, ankle pain, or hip pain. He denied lower extremity weakness or numbness. The pain did not radiate. PHYSICAL EXAMINATION: There was a soft tissue enlargement in posterior medial aspect of left calf that was mildly tender to palpation, soft, and non-mobile. Transillumination of the area was positive. No overlying erythema or skin changes were noted. Calf musculature and strength were normal. There was no tenderness along the rest of the gastrocnemius or Achilles tendon and no pretibial edema was present. Neurovascular examination was unremarkable. DIFFERENTIAL DIAGNOSIS: 1. Deep Vein Thrombosis 2. Synovial Cyst 3. Abscess 4. Morel-Lavallée lesion 5. Lipoma 6. Hematoma TESTS AND RESULTS: - Knee x-rays: Grossly normal; generally preserved joint space, with osteophyte formation and mild patellofemoral arthritis - Bedside ultrasound of calf: Large, hypoechoic, cystic appearance; connected with a small stalk to the posterior knee joint capsule (popliteal); no vascularity seen on Color Flow Doppler - Fluid analysis: Yellow, hazy; no crystals seen; minimal nucleated cells FINAL/WORKING DIAGNOSIS: Synovial cyst connected to the popliteal aspect of the knee joint TREATMENT AND OUTCOMES: 1. Bedside ultrasound evaluation 2. Aspiration of popliteal cyst, 85cc of straw-colored fluid, sent for analysis 3. ACE wrap recommended in attempt to prevent re-accumulation of fluid 4. Orthopedic evaluation due to re-accumulation of fluid, recommended continued monitoring given asymptomatic nature 5. Could consider surgical excision if becomes symptomatic

Meniscal Root Tears

Meniscus root tears are a specific type of meniscal injury that have gained attention over the past 5 years and have been reported to account for 10% to 21% of all meniscal tears, affecting nearly 100,000 patients annually. Meniscal root tears either are defined as an avulsion of the insertion of the meniscus attachment or complete radial tears that are located within 1 cm of the meniscus insertion. Biomechanical studies have demonstrated that meniscal root injuries interrupt the continuity of the circumferential fibers, and hence lead to failure of the normal meniscal function to convert axial loads into transverse hoop stresses. The most common presenting symptoms in meniscal root tears are posterior knee pain and joint line tenderness, especially with deep squatting.Another common symptom is a popping sound heard while participating in light activities such as ascending stairs or squatting. Magnetic resonance imaging signs of medial meniscus root tears include: (1) medial meniscal extrusion of ≥3 mm in a coronal section; (2) high signal indicating a disruption of the posterior meniscal root region in an axial view; and (3) a “ghost sign,” which is the absence of an identifiable meniscus in the sagittal plane, or increased signal replacing the normally dark meniscal tissue signal at the posterior root attachment. Active patients, regardless of age, should be referred early and considered for a meniscal root repair. Indications for a meniscal root repair include acute, traumatic root tears in patients with nearly normal or normal cartilage and chronic symptomatic root tears in young or middle-aged patients without significant preexisting osteoarthritis.Meniscal root repair has been demonstrated to have high satisfaction rates and superior outcomes to arthroscopic meniscectomy for root tears. To restore the function of the meniscus after medial meniscus root tears, a transosseous meniscal root repair technique is most commonly used. The advantage of this technique is the ability to reduce and fix the meniscal root to the broad anatomic footprint to maximize its healing potential. In addition, the transtibial tunnels may contribute to the release of biological factors that can enhance the healing of the meniscal root repair.

Anatomical study of the innervation of posterior knee joint capsule: implication for image-guided intervention

Background and objectivesPeripheral nerve block is an important component of the multimodal analgesia for total knee arthroplasty. Novel interventional techniques of ultrasound-guided nerve block supplying the posterior knee joint capsule...

Adipose derived stem cells in combination with Fascial derived stem cells for the treatment of osteoarthritis in rat

Objective To evaluate the effect of using Adipose derived mesenchymal stem cells (ADSCs) and Fascial derived mesenchymal stem cells (FDSCs) in the treatment of osteoarthritis in rats. Methods Isolated from rat groin fat pad between adipose mesenchymal stem cells, hind legs between skeletal muscle membrane separation membrane, mesenchymal stem cells were identified after amplification culture, The two cells were mixed in different proportions and divided into groups A (1∶0), B (5∶1), C (1∶1), D (1∶5), E (0∶1) and F (0∶0), a total of 1×106, injected by iodine osteoarthritis joint cavity of rats induced by acetic acid. After 12 weeks of stem cell injection treatment, the posterior limb knee joint samples of each group of rats were obtained for gross and pathological histological evaluation. Results The positive expressions of CD29, CD71 and CD90 of fat mesenchymal stem cells and fascial mesenchymal stem cells were detected, and the negative expressions of CD45 were detected. All of them can be multidirectional induced differentiation. When the two cells were mixed by 1∶1, the gross score was: Group A (4.25± 0.96), group B (4.83 ±1.11), group D (4.41 ±0.90), group E (4.91 ±0.79), group F (5.75 ±1.21) were all higher than group C (2.92±0.79, P=0.010), The pathological histological score of group A (8.16 ± 1.46), group B (7.41 ±1.78), group D (8.08 ±1.44), group E (8.83±1.47) and group F (15.58±2.77) were all higher than group C (5.83±1.85, P=0.010). Conclusion When the ratio of fat mesenchymal stem cells and fascia mesenchymal stem cells is 1∶1, the best effect of cartilage repair is achieved. Key words: Osteoarthritis; Mesenchymal stem cells; 3D culture; Inducing differentiation; Intraventricular injection; Cartilage repair

Effect of acupuncture plus thunder-fire moxibustion on MMP-3, TIMP-1 and TGF-β1 in rats with knee osteoarthritis

To observe the effect of acupuncture plus thunder-fire moxibustion on the expressions of matrix metalloproteinase-3 (MMP-3), tissue inhibitor of metalloproteinase-1 (TIMP-1) and transforming growth factor-β1 (TGF-β1) in cartilage of knee osteoarthritis (KOA) rats, and to explore the mechanism of acupuncture plus thunder-fire moxibustion in the treatment of KOA. Thirty Sprague-Dawley (SD) rats were randomly divided into a blank control group, a model group and an acupuncture-moxibustion group by random digits table, 10 rats in each group. Rats in the model group and the acupuncture-moxibustion group were injected with papain in the right posterior knee joint to prepare the models. The levels of MMP-3 and TIMP-1 in rat synovium of each group were measured by enzyme-linked immunosorbent assay (ELISA) after 2 weeks of treatment. The level of TGF-β1 was determined by Motic B5 Micro-camera system. The levels of MMP-3 and TIMP-1 in the cartilage of the model group were significantly higher than those in the blank control group (all P<0.01); the levels of MMP-3 and TIMP-1 in the acupuncture-moxibustion group were lower than those in the model group, and the between-group differences were statistically significant (all P<0.05). The levels of MMP-3 and TIMP-1 in the acupuncture-moxibustion group were higher than those in the blank control group, and the differences were statistically significant (all P<0.05). The level of TGF-β1 in cartilage tissues of the model group was significantly lower than that in the blank control group (P<0.01); the level of TGF-β1 in the acupuncture-moxibustion group was higher than that in the model group (P<0.05), but it was lower than that in the blank control group, and the between-group difference was statistically significant (P<0.05). Acupuncture plus thunder-fire moxibustion can effectively recover the abnormal expressions of MMP-3 and TIMP-1 in KOA model rats and somewhat up-regulate TGF-β1, which may be one of its mechanisms of acupuncture plus thunder-fire for KOA.

Principles of posterior knee joint instability treatment (literature review)

Damage of posterior crucial ligament postern-lateral stabiliz­ing structures is a significant injury to the knee. Incomplete diagnosis of lesions in the acute period of trauma and subse­quent inadequate treatment leads to functional instability and rapid progression of degenerative processes. Objective: based on the analysis of scientific literature to identify further direc­tion for improving surgical techniques and improving outcomes of patients with posterior instability of the knee joint. Meth­ods: keyword search on problems of diagnosis, classification and selection method for treating posterior knee instability in the english-speaking academic libraries, databases Pubmed, Medline, Cochrane library and the Russian media over the past 15 years. Results: mechanisms of posterior crucial ligament inju­ry are very diverse. Damage can be isolated or combined, have a chronic course. In recent years, increased interest in the re­construction of all the internal structures of the knee. Reports of the functional results of posterior crucial ligament surgi­cal treatment is less than anterior crucial ligament. The sig­nificance of the problem is associated with low frequency and less surgical treatment of posterior crucial ligament injuries, as well as the heterogeneity of acute, chronic and combined it with the potential damage involving posterolateral joint. Damage of posterior crucial ligament often remains unrecognized and therefore untreated. The authors analyzed the methods used to­day to treat patients with posterior instability of the knee joint, whereby defined prospects for improving surgical techniques and improving outcomes.

Temporal gene expression profiling of the rat knee joint capsule during immobilization-induced joint contractures.

BackgroundContractures of the knee joint cause disability and handicap. Recovering range of motion is recognized by arthritic patients as their preference for improved health outcome secondary only to pain management. Clinical and experimental studies provide evidence that the posterior knee capsule prevents the knee from achieving full extension. This study was undertaken to investigate the dynamic changes of the joint capsule transcriptome during the progression of knee joint contractures induced by immobilization. We performed a microarray analysis of genes expressed in the posterior knee joint capsule following induction of a flexion contracture by rigidly immobilizing the rat knee joint over a time-course of 16 weeks. Fold changes of expression values were measured and co-expressed genes were identified by clustering based on time-series analysis. Genes associated with immobilization were further analyzed to reveal pathways and biological significance and validated by immunohistochemistry on sagittal sections of knee joints.ResultsChanges in expression with a minimum of 1.5 fold changes were dominated by a decrease in expression for 7732 probe sets occurring at week 8 while the expression of 2251 probe sets increased. Clusters of genes with similar profiles of expression included a total of 162 genes displaying at least a 2 fold change compared to week 1. Functional analysis revealed ontology categories corresponding to triglyceride metabolism, extracellular matrix and muscle contraction. The altered expression of selected genes involved in the triglyceride biosynthesis pathway; AGPAT-9, and of the genes P4HB and HSP47, both involved in collagen synthesis, was confirmed by immunohistochemistry.ConclusionsGene expression in the knee joint capsule was sensitive to joint immobility and provided insights into molecular mechanisms relevant to the pathophysiology of knee flexion contractures. Capsule responses to immobilization was dynamic and characterized by modulation of at least three reaction pathways; down regulation of triglyceride biosynthesis, alteration of extracellular matrix degradation and muscle contraction gene expression. The posterior knee capsule may deploy tissue-specific patterns of mRNA regulatory responses to immobilization. The identification of altered expression of genes and biochemical pathways in the joint capsule provides potential targets for the therapy of knee flexion contractures.

Popliteal artery injury following traumatic knee joint dislocation in a 14-year-old boy: A case report and review of the literature

Posterior knee joint dislocation associated with injury of the popliteal artery in children is an extremely rare condition. Rapid diagnosis and treatment are essential for limb salvage and function. We reported a 14-year-old boy who suffered traumatic displacement of the right knee and contusion of the popliteal artery during motorcycle accident. The diagnosis was confirmed using Doppler and duplex ultrasonography and digital substraction transfemoral arteriography. The urgent surgical procedure was performed using posterior approach to the popliteal artery. During the surgical exploration, rupture of the posterior cruciate ligament associated with thrombosed popliteal artery have been found. The damaged popliteal artery was resected and replaced with autologous saphenous vein graft. The last stage of the procedure was a transosseous femoral fixation of posterior circuate ligament. A 3-year-follow-up after the surgery demonstrated intact arterial perfusion and very good function of the knee with a minimal difference as compared with the contralateral knee. Combined orthopedic and vascular injuries are very rare in children. They require combined treatment.

Image of the Month: Answer

Journal of Paediatrics and Child HealthVolume 49, Issue 2 p. 162-162 ViewpointFree Access Image of the Month: Answer First published: 18 February 2013 https://doi.org/10.1111/jpc.12096_2AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Radiological findings are consistent with a diagnosis of synovial chondromatosis, confirmed by histological findings after synovectomy. Synovial chondromatosis is an uncommon, monoarticular, proliferative disease of the synovium that usually affects large joints. The disorder is characterised by the presence in the synovial space of multiple highly cellular cartilaginous nodules, that results from metaplasia of the synovial tissue. As the disease progresses, the cartilaginous nodules become partially calcified, the synovium thickens and the joint surfaces may become eroded. Only when calcification of nodules occurs, radiographs reveal radiopaque loose bodies within the joint. Initially MRI can be negative, because in unmineralised synovial chondromatosis the signal intensity of the nodules resembles that of fluid.1 Malignant transformation has been reported. Clinical manifestations can mimic a monoarticular JIA since, as in our case, it may be characterised by recurrent relapses and remissions. Repeating a radiograph is therefore mandatory in all cases of oligoarticular JIA characterised by frequent relapses. The differential diagnosis should consider tubercular arthritis.2 Knee tuberculosis is characterised by a chronic indolent monoarthritis resulting in destruction of the joint. Tuberculin skin test and culture of the synovial fluid confirm the diagnosis. Other conditions to be considered are intra-articular chondroma and synovial sarcoma, which require histologic evaluation. Synovial fluid examination, MRI and biopsy might be useful to exclude pigmented villonodular synovitis, haemarthrosis, vascular malformation, foreign body synovitis and sarcoidosis. The treatment of synovial chondromatosis is surgical. Open surgery or arthroscopic intervention is performed with resection of the diseased synovium and removal of any loose intra-articular bodies. Recurrence is frequent after partial synovectomy, hence total synovectomy has been suggested as the preferred treatment.3 References 1 Murphey MD, Vidal JA, Fanburg-Smith JC, Gajewski DA. Imaging of synovial chondromatosis with radiologic-pathologic correlation. Radiographics 2007; 27: 1465– 1488. CrossrefPubMedWeb of Science®Google Scholar 2 Kiritsi O, Tsitas K, Grollios G. A case of idiopathic bursal synovial chondromatosis resembling rheumatoid arthritis. Hippokratia 2009; 13: 61– 63. CASPubMedWeb of Science®Google Scholar 3 Jesalpura JP, Chung HW, Patnaik S, Choi HW, Kim JI, Nha KW. Arthroscopic treatment of localized synovial chondromatosis of the posterior knee joint. Orthopedics 2010; 33: 49. CrossrefPubMedGoogle Scholar Volume49, Issue2February 2013Pages 162-162 ReferencesRelatedInformation