Knee Joint Stability Research Articles

Effects of Muscle Activation Pattern and Stability of the Lower Extremity's Joint on Falls in the Elderly Walking -Half a Year Prospective Study-

Objective: The aim of this study was to determine the peak torques of the knee and ankle joint and local stability of the lower extremity's joints, and muscle activation patterns of the lower extremity's muscles between fallers and non-fallers in the elderly women during walking. Method: Four elderl...

Effect of posterior oblique ligament repair on rotational stability of knee joint

To investigate effect of posterior oblique ligament (POL) repair on the rotational stability of the knee joint for the medial collateral ligament (MCL) combined with anterior cruciate ligament (ACL) ruptures. The clinical data of 50 patients (50 knees) with grade-3 MCL-ACL combined injuries who met the selection criteria between January 2013 and December 2015 were retrospectively analyzed. All ACLs were reconstructed with autogenous tendon and the superficial and deep layers of MCLs were sutured; then, POLs were also sutured in 25 patients of repair group and only received conservation treatment postoperatively in 25 patients of conservation group. There was no significant difference in gender, age, disease duration, and preoperative KT-1000 measuring, medial joint space opening, International Knee Documentation Committee (IKDC) score, visual analogue scale (VAS) score, and knee range of motion between the two groups ( P>0.05). All incisions of the two groups healed by first intention, no surgical related complications occurred. All patients were followed up, with follow-up time of 28-56 months (mean, 38.1 months) in repair group and 26-55 months (mean, 29.1 months) in conservation group. At last follow-up, the IKDC score, VAS score, KT-1000 measuring, medial joint space opening, and knee range of motion significantly improved in the two groups when compared with preoperative ones ( P<0.05); but there was no significant difference between the two groups ( P>0.05). The Slocum test showed that there was no instability of the anterior medial rotation in the two groups. The POL repair can't obtain more medial stability after ACL reconstruction and MCL repair (superficial and deep layers) for patients who have MCL-ACL combined injuries.

Short-term efficacy of arthroscopic posterior cruciate ligament reconstruction using double posteromedial portals

Objective To investigate the short-term clinical efficacy of arthroscopic reconstruction of posterior cruciate ligament (PCL) via double posteromedial portals. Methods A retrospective case series study was performed on the clinical data of 29 patients with PCL injury from January 2013 to January 2018 admitted to Xuancheng People's Hospital of Anhui province. There were 15 males and 14 females, with an average age of 49.6 years (range, 27-61 years). There were 13 patients with left knee injury and 16 patients with right knee injury. The combined injuries included five patients with medial meniscus tear, seven patients with lateral meniscus tear, one patient with medial collateral ligament injury, and two patients with lateral medial collateral ligament injury. The average duration from injury to surgery was 14.1 days ( range, 5-97 days). All patients received arthroscopic PCL reconstruction surgery using double posteromedial portals. The operation time and intraoperative blood loss were recorded. The posterior drawer test, reverse Lachman test, posterior translation, and Lysholm knee score scale were used to evaluate knee function preoperatively and 6 months after operation. The complications were recorded. Results All patients were followed up for 6-22 months (mean, 12 months). The operation time was (63.3±9.5) minutes, and the intraoperative blood loss was (48.9±22.8)ml. The posterior drawer tests and reverse Lachman tests of all patients turned to be negative 6 months after surgery. Preoperatively, the posterior translation and Lysholm score were (11.2±3.3)mm and (42.7±12.2)points, respectively. At 6 months postoperatively, the posterior translation and Lysholm score were (2.2±0.5)mm and (86.3±9.0)points, respectively (P<0.05). No complication such as infection and neurovascular injury occured. Conclusion The technique of arthroscopic PCL reconstruction surgery using double posteromedial portals has the advantages of good knee joint stability, less tibial posterior translation, and fast function recovery with satisfactory short-term efficacy. Key words: Knee injuries; Arthroscopy; Posterior cruciate ligament; Reconstruction

Classification of gait patterns in patients with unilateral anterior cruciate ligament deficiency based on phase space reconstruction, Euclidean distance and neural networks

The anterior cruciate ligament (ACL) is one of the most important structures of the knee joint which plays a significant role in controlling knee joint stability. Patients with unilateral ACL deficiency often show alterations of their gait patterns in the deficient side in comparison with the unaffected contralateral side. Gait analysis is widely used to detect biomechanical changes in the lower limbs, aiming at diagnosing ACL injury, establishing physical therapy treatments or surgery, monitoring the progression of ACL deficiency over time. This paper proposes new combined methods to classify gait patterns between ACL deficient (ACL-D) knee and contralateral ACL-intact (ACL-I) knee in patients with unilateral ACL deficiency by using phase space reconstruction (PSR), Euclidean distance (ED) and neural networks. First knee, hip and ankle kinematic parameters are extracted and phase space has been reconstructed. The properties associated with the gait system dynamics are preserved in the reconstructed phase space. For the purpose of classification of ACL-D and ACL-I knee gait patterns, three-dimensional (3D) PSR together with EDs has been used. These measured parameters show significant difference in gait dynamics between the two groups and have been utilized to form the feature set. Neural networks are then used as the classifier to distinguish between ACL-D and ACL-I knee gait patterns based on the difference of gait dynamics between the two groups. Finally, experiments are carried out on forty-three patients to assess the effectiveness of the proposed method. By using the leave-one-out cross-validation style under normal and fast walking speed conditions, the correct classification rates for discriminating between ACL-D and ACL-I knees are reported to be $$95.4\%$$ and $$93.3\%$$, respectively. Compared with other state-of-the-art methods, the results demonstrate superior performance and support the validity of the proposed method.

Follow-up study on autogenous osteochondral transplantation for cartilage defect of knee joint

To evaluate clinical effect of autologous osteochondral transplantation in treating localized knee cartilage defects. Fifteen patients with knee cartilage defects were treated by autologous osteochondral transplantation from January 2007 to January 2008, including 8 females and 7 males, aged from 23 to 45 years old. Preoperative and postoperative KSS score at 10 years were compared. All patients were followed up for 10.0 to 10.7 years, with an average of(10.2±0.3) years. Clinical score of KSS was improved from 38.86±4.09 to 85.07±2.19 at 10 years after operation(P<0.05), functional score increased from 3.33±4.88 to 82.67±4.58 at 10 years after operation(P<0.05), KSS score was improved form 42.20±7.84 befor operation to 167.73±6.29 at 10 years after operation, and had statistical differences before and after operation. While there was no statistical difference in stability of knee joint(P>0.05). All patients had no other complications. Through long-term follow-up of patients with cartilage defect in knee treated by autologous bone cartilage transplantation showed that this method could effectively improve function of knee joint and alleviate pain. So it is an effective method for repair of osteochondral defect.

Surface analysis of sheep menisci after meniscectomy via infrared attenuated total reflection spectroscopy.

Menisci are very important fibrocartilaginous tissue, which maintain biomechanical functions and physiological stabilization of knee joint. Meniscectomy is known as a surgery to recover partial functions from acute meniscus tears. However, the late consequences of total or partial meniscectomy include signs of osteoarthritis and even ligament instability. Infrared attenuated total reflection (IR-ATR) spectroscopy is a very useful technique, which can reveal molecular characteristics via the analysis of vibrational bands. The present study has employed IR-ATR spectroscopy to investigate sheep menisci samples after meniscectomy in a label-free fashion. Several differences of peak absorbance change and peak shift were observed between the native healthy samples and the meniscectomy samples in distinct IR wavenumber regions, such as amide I band, amide II band, C-H bending band as well as the sugar band region. Combining the results from the collagen protein IR spectra, it can be speculated that six months after meniscectomy collagen fibrils on the incision lose its ordered arrangement and a decrease in the triple helical structure of collagen fibril is observed. In addition, the collagen fibrils and proteoglycan content might also be slight varied after meniscectomy.

Eight-year results of transtibial nonanatomic single-bundle versus double-bundle anterior cruciate ligament reconstruction: Clinical, radiologic outcomes and survivorship.

To compare the long term outcomes of transtibial nonanatomic single-bundle (SB) and double-bundle (DB) anterior cruciate ligament (ACL) reconstruction. Between January 2008 and September 2010, we retrospectively evaluated 377 patients who underwent primary ACL reconstruction and who were available at 8 years of follow-up. Patients who received transtibial nonanatomic SB ACL reconstruction ( n = 263) were assigned to group SB and DB ACL reconstruction ( n = 114) to group DB. The patients were assessed with the International Knee Documentation Committee (IKDC), the Lysholm scores, Tegner activity score, knee joint stability tests, and patellofemoral osteoarthritis (OA) findings using the Kellgren-Lawrence (K-L) classification. Contralateral ACL (CACL) injury was also evaluated. Thirteen patients underwent revision ACL surgery during the follow-up. Ultimately, 256 patients in group SB and 108 patients in group DB were available at the 8-year follow-up. At final follow-up, the IKDC subjective score ( p = 0.04) and Lysholm score ( p = 0.02) showed significantly superior results in group DB compared to group SB. However, there was no significant difference of Tegner activity score ( p = 0.30), range of motion ( p = 0.81), and knee joint stability tests. There was significant progression of patellofemoral OA between preoperative and final follow-up in ipsilateral knee of both groups but not significant progression in contralateral knee. However, there was no significant difference between the two groups at the follow-up. There were 2.7% ipsilateral ACL graft failure in group SB, compared with 5.2% in group DB ( p = 0.12) and 6.4% CACL tear in group SB, compared with 5.2% in group DB ( p = 0.65). The mean survivorship of ACL graft was 9.47 ± 0.05 years (95% confidence interval (CI), 9.36-9.58) in group SB and 9.87 ± 0.16 years (95% CI, 9.54-10.20) in group DB, and there was no significant difference ( p = 0.25). DB ACL reconstruction resulted in significantly better clinical IKDC subjective scores and Lysholm scores. However, most of the differences in clinical scores were small, and the clinical relevance of this difference is unknown. In addition, there was no significant difference in Tegner activity score, knee joint stability tests, patellofemoral OA, and survivor rate of the ACL graft and CACL after reconstruction after a minimum of 8-year follow-up. Level of Evidence: Cohort study; level of evidence, 3.

The Importance of the Knee Joint Meniscal Fibrocartilages as Stabilizing Weight Bearing Structures Providing Global Protection to Human Knee-Joint Tissues.

The aim of this study was to review aspects of the pathobiology of the meniscus in health and disease and show how degeneration of the meniscus can contribute to deleterious changes in other knee joint components. The menisci, distinctive semilunar weight bearing fibrocartilages, provide knee joint stability, co-ordinating functional contributions from articular cartilage, ligaments/tendons, synovium, subchondral bone and infra-patellar fat pad during knee joint articulation. The meniscus contains metabolically active cell populations responsive to growth factors, chemokines and inflammatory cytokines such as interleukin-1 and tumour necrosis factor-alpha, resulting in the synthesis of matrix metalloproteases and A Disintegrin and Metalloprotease with ThromboSpondin type 1 repeats (ADAMTS)-4 and 5 which can degrade structural glycoproteins and proteoglycans leading to function-limiting changes in meniscal and other knee joint tissues. Such degradative changes are hall-marks of osteoarthritis (OA). No drugs are currently approved that change the natural course of OA and translate to long-term, clinically relevant benefits. For any pharmaceutical therapeutic intervention in OA to be effective, disease modifying drugs will have to be developed which actively modulate the many different cell types present in the knee to provide a global therapeutic. Many individual and combinatorial approaches are being developed to treat or replace degenerate menisci using 3D printing, bioscaffolds and hydrogel delivery systems for therapeutic drugs, growth factors and replacement progenitor cell populations recognising the central role the menisci play in knee joint health.

Changes in physical inactivity during supervised educational and exercise therapy in patients with knee osteoarthritis: a prospective cohort study

Abstract Background Physical inactivity is a global problem and patients with knee osteoarthritis (OA) are predisposed to inactivity and its health-related consequences. Current guidelines recommend exercise as primary treatment but whether this affects time spent physically inactive is unknown. The objective was to investigate changes in physical inactivity among individuals with knee OA following an educational and exercise program. Methods Pragmatic prospective cohort study performed in six physical therapy clinics in Denmark offering a nationwide education and exercise program for knee OA. The program consists of physiotherapy guided education and group-based or home exercise sessions, performed biweekly for approximately eight weeks. The exercises target knee and hip joint stability as well as focus on increasing muscle strength. Primary outcome was time spent physically inactive (min/day), measured with a tri-axial accelerometer mounted on the lateral side of the thigh during the entire exercise program duration. OA symptoms were assessed using the Knee injury and Osteoarthritis Outcome Score (KOOS). Results Thirty-two individuals with knee OA were analyzed. From baseline to post-intervention, no changes occurred in average time spent physically inactive (mean change: + 16.2 min [95% CI − 15.7 to 48.1]; P = 0.31), but statistically significant improvements in KOOS pain (+ 6.7 points [95% CI 2.3 to 11.0]; P = 0.0032) and KOOS function (+ 5.8 points [95% CI 1.9 to 9.7]; P = 0.0046) were found. Conclusions Participating and completing a widely adopted education and exercise program are not associated with spontaneous improvements in physical inactivity despite changes in self-reported pain and function. Interventions specifically targeting physical inactivity are needed. Registration number: www.clinicaltrials.gov : NCT03125954 .

مخاطر الإصابة بالرباط الصليبي الأمامي: مراجعة أدبية

الرباط الصليبي الأمامي هو أحد أربطة الركبة الهامة التي تلعب دوراً هاماً في الحفاظ على ثبات مفصل الركبة. وآلية الإصابة غالبا ما تكون جراء عدم الاحتكاك المباشر بنسبة65% مع الخصم أثناء الأنشطة البدنية التي تتطلب تغييراً مفاجئًا لاتجاه اللعب، مثل: القفز والهبوط، وحركات دوران القدم. أن معدل الإصابة بقطع الرباط الصليبي ما زال عاليا بين عموم الناس والرياضيين بشكل خاص للفئة العمرية ما بين 15 إلى 25 سنة. إن الهدف من هذه المراجعة الأدبية هو تحليل ودراسة اأصسباب والمخاطر المحتملة للإصابة بقطع الرباط الصليبي الأمامي في عدة متغيرات و تسليط الضوء عليها منها: العلاقة بين أرضية الملعب والحذاء، وزاوية العضلة ذات الأربعة رؤوس الفخذية، ارتخاء مفصل الركبة، التقوس الخارجي للركبة، كتلة الجسم، وغيرها. وزيادة فرص الإصابة عادة ما يكون من خلال تداخل واشتراك عدة عوامل بعضها مع بعض أثناء النشاط البدني؛ لذلك يجب الأخذ بعين الاعتبار جميع المعطيات المتعلقة بخطر الإصابة عند تصميم وتخطيط البرامج التدريبية والتأهيلية أثناء التدريب والمنافسات من أجل تقليل فرص الإصابة.

Does anterolateral ligament rupture affect functional outcomes in patients who underwent an anterior cruciate ligament reconstruction?

BackgroundStudies have shown that the anterolateral ligament contributes to knee stability. This study aims to compare the results of postoperative physical examinations, knee joint stability tests, and functional assessment tests of patients with intact anterolateral (AL) ligaments and patients with ruptured anterolateral (AL) ligaments. Material and methodThis study consisted of 101 patients, with at least a 12-month follow-up period, who underwent an anterior cruciate ligament reconstruction between 2010 and 2016, and whose AL ligaments were evaluated by the radiologist with the preoperative and postoperative magnetic resonance images (MRI). Of these patients, 41 had intact AL ligament (Group 1) in MRI and other 60 had ruptured AL ligament (Group 2). Groups were compared according to postoperative physical examinations, knee joint stability tests, and functional assessment tests. ResultsThe average Lysholm score of Group 1 was 94.9 (range: 81–100), and the score of Group 2 was 87.2 (range: 74–100). The modified Cincinnati score of Group 1 was 28.7 (24–30), while the score of Group 2 was 25.6 (21–30). The average IKDC subjective knee evaluation score of Group 1 was 91.9 (range: 83–100), and the score of Group 2 was 86.6 (range: 75–100). The average thigh atrophy value was 1.5 centimeters (cm) in Group 1 and 2.4 cm in Group 2. Thirty-three patients in Group 1 were able to jump over 85% of the distance in single-legged hop test compared to the intact side, while 16 patients in Group 2 were able to jump over this distance successfully.As a result of the analysis, it was determined that the Lysholm activity scoring results, the Modified Cincinnati scoring results, IKDC subjective knee evaluation results, two-cycle IKDC activity scale results, comparison of thigh diameters and the single-legged hop tests of two groups showed a statistically significant difference, and the results of the patients with intact AL ligaments who underwent an ACL reconstruction were found to be better (p < 0.05). No significant difference was found in other examinations and tests. ConclusionSince the rupture of the AL ligament has negative effects on functional outcomes, we think that the reconstruction of the AL ligament in the same session with the ACL reconstruction or later will have a positive effect on functional outcomes.

Surgical Treatment of Meniscal RAMP Lesion.

RAMP lesion, defined as peripheral detachment lesion of posterior horn of medial meniscus, has been shown to accompany anterior cruciate ligament (ACL) ruptures and is thought to play an important role in the knee joint stability. In this study, we aimed to present results of postoperative knee function scores and patient satisfaction after surgical repair of RAMP lesion. We included 15 patients who had undergone knee arthroscopy due to RAMP lesion in 2017. We recorded demographic data, diagnosis, pre- and postoperative International Knee Documentation Committee and Tegner-Lysholm scores of all patients. In this study, we included 15 patients: the number of male and female patients was eight and seven, respectively. The mean age of patients was 26.8 (18-35). Associated injuries included ACL rupture in 12 patients, additional medial meniscus lesion in 3 patients, lateral meniscus lesion in 3 patients, and superomedial patellar plicae syndrome in 2 patients. All patients had the same postoperative rehabilitation protocol. Mean preoperative Tegner-Lysholm knee score was 64.4 (53-75), while it was 82.5 (75-89) postoperatively, and mean preoperative and postoperative Visual Analogue Scale score at last postoperative follow-up were 5.26 (2-8) and 1.06 (0-2), respectively. All differences were found to be statistically significant. Meniscal RAMP lesions are commonly associated with ACL ruptures. RAMP repair significantly increases postoperative knee function scores and patient satisfaction following ACL reconstruction.

THE RELATIONSHIP BETWEEN PERCEIVED SOCIAL SUPPORT AND PSYCHOLOGICAL FACTORS RELATED TO RETURNING TO SPORT IN ADOLESCENTS FOLLOWING ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

Objectives: “Return-to-sport” (RTS) criteria following anterior cruciate ligament (ACL) reconstruction lacks standardization. In addition to functional strength and knee joint stability, psychological factors may also affect readiness to RTS. The present study aimed to assess the association between perceived levels of social support and confidence in RTS among adolescent athletes prior to undergoing ACL reconstruction. We hypothesized that athletes who perceived higher levels of social support would have greater confidence in their ultimate ability to return to their previous level of play after ACL reconstruction. Methods: Fifty-three subjects completed two questionnaires prior to undergoing ACL reconstruction: the Multidimensional Scale of Perceived Social Support (MSPSS) and a psycho-vitality (PV) questionnaire. We performed a multiple linear regression to assess if MSPSS score was associated with confidence in returning to sport (PV score), while controlling for the independent effects of age and gender. Independent sample t-tests were also used to compare MSPSS scores between those who did and did not state that they had doubts in their ability to RTS and those who were and were not willing to settle for a less strenuous sporting activity than previously, based on the PV questionnaire responses. Results: The mean age of participants was 15.6±1.7 years (range 9-18 years) with 42% males. There was no significant association between MSPSS total score (mean= 6.22±0375, range= 4-7) and PV total score (mean= 13.8±3.0, range= 8-18; ß coefficient= -0.63, 95% CI= -1.77, 0.52, p = 0.28). Those who reported doubts in returning to sport did not significantly differ than those who reported no doubts (n=19) in MSPSS total score (6.07±0.82 vs. 6.30±0.70; p = 0.29; Cohen’s d= 0.31). Similarly, those who did and did not respond that they were willing to settle for a less strenuous sporting activity had similar MSPSS scores (6.14±0.81 vs. 6.47±0.45; p= 0.17; Cohen’s d= 0.44). Conclusion: Previous studies suggest that psychological factors play a role in successful RTS, yet the specifics of how this pertains to adolescent athletes remain unknown. The present study suggests that prior to ACL reconstruction, perceived social support does not significantly influence confidence in the ability to ultimately RTS following surgery and subsequent rehabilitation in young athletes. Future studies will aim to correlate these variables between pre-operative and actual RTS time points, as well as to investigate how other factors, such as motivation and self-esteem, are influenced by social support and affect ultimate RTS success.

Computational analysis of knee joint stability following total knee arthroplasty

The overall objective of this study was to introduce knee joint power as a potential measure to investigate knee joint stability following total knee arthroplasty (TKA). Specific aims were to investigate whether weakened knee joint stabilizers cause abnormal kinematics and how it influences the knee joint kinetic (i.e., power) in response to perturbation.Patient-specific musculoskeletal models were simulated with experimental gait data from six TKA patients (baseline models). Muscle strength and ligament force parameter were reduced by up to 30% to simulate weak knee joint stabilizers (weak models). Two different muscle recruitment criteria were tested to examine whether altered muscle recruitment pattern can mask the influence of weakened stabilizers on the knee joint kinematics and kinetics. Level-walking knee joint kinematics and kinetics were calculated though force-dependent kinematic and inverse dynamic analyses. Bode analysis was then recruited to estimate the knee joint power in response to a simulated perturbation.Weak models resulted in larger anterior-posterior (A-P) displacement and internal-external (I-E) rotation compared to baseline (I-E: 18.4 ± 8.5 vs. 11.6 ± 5.7 (deg), A-P: 9.7 ± 5.6 vs. 5.5 ± 4.1 (mm)). Changes in muscle recruitment criterion however altered the results such that A-P and I-E were not notably different from baseline models. In response to the simulated perturbation, weak models versus baseline models generated a delayed power response with unbounded magnitudes. Perturbed power behavior of the knee remained unaltered regardless of the muscle recruitment criteria.In conclusion, impairment at the knee joint stabilizers may or may not lead to excessive joint motions but it notably affects the knee joint power in response to a perturbation. Whether perturbed knee joint power is associated with the patient-reported outcome requires further investigation.

Intra-rater reliability and criterion-related validity of using an accelerometer to measure the impact force and knee joint sway during single-leg drop landing.

[Purpose] This study aimed to clarify the reliability and validity of the impact force and knee joint sway measurement during single-leg drop landing by using a motion sensor with two built-in accelerometers. [Participants and Methods] Ten healthy college students (4 males and 6 females) who joined a basketball club participated in this study. Peak vertical acceleration, time between initial contact and peak vertical acceleration, and knee joint mediolateral sway were measured using the accelerometer during the landing motion. Reliability of the measurement with the accelerometer and the criterion-related validity between the accelerometer and force plate data were examined. [Results] The intraclass correlation coefficients indicated a peak vertical acceleration of 0.88, time between initial contact and peak vertical acceleration of 0.96, and knee joint mediolateral sway of 0.62. The magnitude and timing of the peak values between both measurement instruments showed high validity. [Conclusion] The measurement method using a motion sensor for the evaluation of the impact force and knee joint sway during landing has a moderate to high reliability and criterion-related validity. A motion sensor measurement might be a useful and easy method for evaluating landing impact force and knee joint stability.

Novel pin jointed moment connection for cold-formed steel trusses

Portal frame structures, made up of cold-formed steel trusses, are increasingly being used for lightweight building construction. A novel pin-jointed moment connector, called the Howick Rivet Connector (HRC), was developed and tested previously in T-joints and truss assemblage to determine its reliable strength, stiffness and moment resisting capacity. This paper presents an experimental study on the HRC, in moment resisting cold-formed steel trusses. The connection method is devised where intersecting truss members are confined by a gusset connected by HRCs to create a rigid moment connection. In total, three large scale experiments were conducted to determine the elastic capacity and cyclic behaviour of the gusseted truss moment connection comprising HRC connectors. Theoretical failure loads were also calculated and compared against the experimental failure loads. Results show that the HRCs work effectively at carrying high shear loads between the members of the truss, enabling rigid behaviour to be developed and giving elastic behaviour without tilting up to a defined yield point. An extended gusset connection has been proposed to maximize the moment carrying capacity in a truss knee connection using the HRCs, in which they are aligned around the perimeter of the gusset to maximize the moment capacity and to increase the stability of the truss knee joint.

Acute Correction of Varus Knee by Biplanar Medial Opening-Wedge High Tibial Osteotomy and Fixation with TomoFix Plate

Background: Biplanar medial opening wedge high tibial osteotomy (MOWHTO) is a treatment method that allows adequate correction of symptomatic varus knee deformity. However, MOWHTO tends to decrease patellar height and increase the posterior tibial slope, which can affect the knee joint stability. Objective: The aim of this study was to describe the technique of biplanar MOWHTO and fixation by TomoFix plate, as well as to evaluate the accuracy of the planned correction and the postoperative tibial slope. Patients and Methods: This prospective cohort study was conducted on patients who presented with varus knee deformity and underwent biplanar MOWHTO and fixation by TomoFix plate during the period from March 2016 to March 2017. Assessment of patients included pre- and postoperative Knee and function scores, mechanical femorotibial angle (mFTA), posterior tibial slope angle (pTSA), range of motion (ROM) and radiological evaluation of the healing of the osteotomy site. Results: The recruited patients were 13 (8 men and 5 women), with average age 31.7 years old. The knee and functional scores improved from the preoperative mean of 45 and 41 to the postoperative mean of 85 and 72 points, respectively. The average knee flexion was 115 degrees, which at the final follow-up remained unchanged except for one case. The mean preoperative mFTA was 13.5° varus and decreased post-operatively to a mean of 3° valgus. The average postoperative follow-up period was 12 months (10 - 18 M). Conclusion: The biplanar MOWHTO allows preservation of posterior tibial slope while correcting the varus knee adequately.

What to Know for Selecting Cruciate-Retaining or Posterior-Stabilized Total Knee Arthroplasty.

There has been continuing debate about the superiority of cruciate-retaining (CR) total knee arthroplasty (TKA) versus posterior-stabilized (PS) TKA for obtaining knee joint stability with functional improvement. Many surgeons tend to select the type of prosthesis on the basis of their own training and experience. However, the selection must be based on a great store of knowledge rather than on the surgeon's preconceptions or preferences. CR TKA may not be feasible in certain settings: posterior cruciate ligament insufficiency, severe deformity, and history of trauma or surgery. The risk of conversion from a CR type prosthesis to a PS type prosthesis might be high in patients with severe flexion contracture, steep posterior slope, and small femoral component size. The above factors should be carefully considered for an appropriate selection of the type of prosthesis. The surgeon should have a clear understanding on the technical differences between CR and PS TKAs. The amount of distal femoral resection, femoral component size, and tibial slope are particularly crucial for successful TKA. Unless they are meticulously determined, stiffness or instability will ensue, which can be difficult to resolve afterwards. There was no notable difference in functional outcome, range of motion, kinematics, and survival rate between CR and PS TKAs in most previous studies. Strict adherence to surgical indications and solid understanding of differences in surgical principles might be more important than the selection of either a CR or PS prosthesis.

Computational study of knee joint stability and double-bundle structure of anterior cruciate ligament

Computational study of knee joint stability and double-bundle structure of anterior cruciate ligament

Operative Versus Conservative Treatment of Anterior Cruciate Ligament Rupture.

Anterior cruciate ligament (ACL) rupture is a serious injury in patients who are typically young and athletically active, with potential long-term complica- tions including functional limitation, posttraumatic osteoarthritis of the knee, and impaired quality of life. ACL reconstruction is now considered the gold standard of treatment for regaining stability and improving knee function. Conservative treatment is an alternative. To compare operative and conservative treatment, we reviewed pertinent publications retrieved by a systematic search in Ovid MEDLINE, the Cochrane Database of Systematic Reviews, and other databases. PROSPERO registration of the study protocol: CRD42017060462 on 31 March 2017. 13 publications concerning a total of 1246 patients were included in the analysis; only two were reports of randomized controlled trials (RCTs). In one of the RCTs, ACL reconstruction was found to yield better functional outcomes than con- servative management. The other RCT did not reveal any harm from initial conser- vative management, although the conservative-to-operative crossover rate in this trial was 51%. The functional outcomes were heterogeneous. In six observational studies, knee function was significantly better after surgery; in seven others, it was not. Five out of nine analyses in which knee-joint stability was restored after surgery showed superior functional outcomes after ACL reconstruction compared to conser- vative management. Three studies in which no satisfactory postoperative knee-joint stability was found did not show any functional difference between surgery and conservative management. On the basis of RCTs published to date, it cannot be definitively con- cluded whether surgery or conservative (expectant) management of ACL rupture yields a better functional outcome. There is a trend in observational studies toward better functional outcomes after ACL reconstruction. As an average across studies, conservative treatment fails in 17.5% (± 15.5%) of patients.