Chronic Anterior Cruciate Ligament Research Articles

Classification of Gait Patterns Using Kinematic and Kinetic Features, Gait Dynamics and Neural Networks in Patients with Unilateral Anterior Cruciate Ligament Deficiency

The anterior cruciate ligament (ACL) plays an important role in controlling knee joint stability. The literature provides conflicting information on whether patients with ACL deficiency exhibits gait adaptations. The aim of this study is to investigate if the use of neural networks with a new pattern recognition-based method can differentiate gait patterns between ACL deficient (ACL-D) knee and contralateral ACL-intact (ACL-I) knee in patients with unilateral ACL deficiency. The proposed method is divided into two stages. In the training stage, kinematic and kinetic gait variables are measured and compared between the two lower extremities. Gait dynamics underlying gait patterns of ACL-D and ACL-I knees are locally accurately modeled and approximated by radial basis function (RBF) neural networks via deterministic learning theory. The derived knowledge of approximated gait dynamics is preserved in constant RBF networks. In the classification stage, a bank of dynamical estimators is constructed using the preserved constant RBF networks to represent the learned training gait patterns. By comparing the set of estimators with a test gait pattern, the generated average $$L_1$$ norms of errors are taken as the difference and classification measure between the training and test gait patterns. 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 95.9 $$\%$$ and 94.0 $$\%$$ , respectively. Compared with other state-of-the-art methods, the results demonstrate that gait alterations in the presence of chronic ACL deficiency can be detected with superior performance and support the validity of the proposed method.

Side-to-Side Differences in Varus Thrust and Knee Abduction Moment in High-Functioning Individuals With Chronic Anterior Cruciate Ligament Deficiency

Background: There is evidence that frontal plane knee joint motion plays a crucial role in the pathogenesis of knee osteoarthritis, yet investigation of individuals with chronic anterior cruciate ligament–deficient (ACLD) knees remains sparse. Purpose: To investigate (1) if individuals with chronic ACLD knees demonstrate higher biomechanical measures of medial knee load as compared with their anterior cruciate ligament–intact (ACLI) knees, (2) if differences in static knee alignment of the ACLD knee will demonstrate a difference in the magnitude of biomechanical measures of medial knee load when compared with the ACLI knee, and (3) the side-to-side concordance of varus thrust among individuals with chronic ACLD knees. Study Design: Descriptive laboratory study. Methods: Participants were sourced from a metropolitan orthopaedic surgeon group. Those who met the inclusion criteria and agreed to participate underwent a 3-dimensional gait analysis assessment to measure knee adduction moment (KAM), knee flexion moment (KFM), KAM peaks, KAM impulse, and varus thrust. Frontal plane knee static alignment was measured with a digital inclinometer fixed to medical calipers. The participants were divided according to their static knee alignment (neutral, varus, and valgus) for subgroup analysis. Peak knee angular velocity and frontal plane knee angle were used to establish if a participant was walking with a knee thrust. An individual was deemed to have knee thrust during gait if the largest frontal plane knee movement coincided with the peak knee angular velocity that occurred within the first 30% of stance phase. Results: Forty-five participants were recruited. The mean (SD) time from injury was 34.5 (55.6) months. ACLD knees did not demonstrate higher mean KAM and KFM (P > .5) or early-stance peak KAM (P = .3-.8) and KAM impulse (P = .3-.9) as compared with ACLI knees as a whole group or when the varus, neutral, and valgus alignment subgroups were investigated separately. Twenty-three percent (n = 9) of the participants had a varus thrust at the ACLD or ACLI knee, 44% (n = 4) had a varus thrust at the ACLD knee, and 22% (n = 2) had varus thrust at both knees. Conclusion: There were no side-to-side differences in mean KAM and KFM and early-stance peak KAM and KAM impulse among high-functioning individuals with chronic unilateral ACLD knees. There was a low prevalence of varus thrust among high-functioning individuals with chronic unilateral ACLD knees.

Primary Anterolateral Ligament Rupture in Patients Requiring Revision Anterior Cruciate Ligament Reconstruction: A Retrospective Case-Control Magnetic Resonance Imaging Review

To compare the initial rate of anterolateral ligament (ALL) injury at the time of anterior cruciate ligament (ACL) rupture in patients who subsequently experienced ACL reconstruction graft failure versus patients who did not experience subsequent ACL reconstruction graft failure. Our institution's electronic medical record database was queried for patients who underwent primary ACL reconstruction with subsequent ACL graft rupture. Exclusion criteria included unavailable MRI scan, chronic ACL injury, multi-ligamentous injury, previous ACL reconstruction, and age younger than 13 or older than 50years. Each patient was paired with an age-, gender-, and graft-matched control who underwent ACL reconstruction without subsequent graft rupture. Each patient was diagnosed with an intact, partially injured, or fully ruptured ALL on initial MRI. The location of ALL injury was also noted. The incidence and location of ALL rupture were compared using χ2 analysis. 1,967 patients underwent primary ACL reconstruction. 128 patients experienced ACL graft rupture, and 55 patients (43%) had MRI scans available for review. 39 of these patients fulfilled inclusion criteria and were matched with a control patient. In the revision group, the ALL was diagnosed as intact, partially torn, and completely torn in 17, 14, and 8 patients, respectively, compared to 18, 13, and 8patients, respectively in the control group. No difference was found in frequency of ALL rupture (Pearson χ2= 0.066; P= .968) or rupture location (Pearson χ2 = 4.00, P = 0.135). The incidence of initial ALL injury as documented on MRI was not different in patients who experienced subsequent ACL graft rupture compared with patients who did not experience ACL graft rupture after primary ACL reconstruction. The ALL was more commonly injured on the tibial side in patients with ACL graft rupture and femoral-sided lesions were more common in control patients. Level III, prognostic case-control study.

Modified Lemaire extra-articular stabilisation of the knee for the treatment of anterolateral instability combined with diffuse pigmented villonodular synovitis: a case report

BackgroundDiffuse pigmented villonodular synovitis (PVNS) of the knee is a rare proliferative joint disease associated with high recurrence rates following surgical treatment. Intra-articular joint instability in conjunction with PVNS implies complex reconstructive strategies due to the destructive nature of the disease.Case presentationHere, we present the case of a young patient with refractory PVNS and a chronic ipsilateral anterior cruciate ligament (ACL) rupture. Clinically, the patient presented with a grade 3 pivot shift phenomenon, indicating anterolateral rotational instability. Usually, PVNS implies a contraindication for ACL reconstruction due to the degenerative and pro-inflammatory joint microenvironment that is induced and maintained by PVNS. Therefore, we have performed a modified Lemaire extra-articular stabilization resulting in significant clinical improvement and subjective joint stability. In the latest follow-up examination at 12 months, the patient reported subjective joint stability and no swelling. In the clinical examination, the patient showed dynamic joint stability during walking. Additionally, the patient presented with grade 0 in pivot-shifting compared to the contralateral knee. The Lachman test exhibited no increased side-to-side difference and a firm endpoint.ConclusionsExtra-articular anterolateral stabilisation of the knee in patients having anterolateral knee instability combined with PVNS is a safe and efficient surgical treatment option yielding significant clinical improvement as well as subjective joint stability.

Arthroscopic and 3D CT Scan Evaluation of Femoral Footprint of the Anterior Cruciate Ligament in Chronic ACL Deficient Knees.

The outcome of single-bundle anterior cruciate ligament (ACL) reconstruction depends largely on the anatomic placement of bone tunnel. The lateral intercondylar ridge (LIR) and bifurcate ridge (BR) are useful bony landmarks for femoral tunnel placement. The purpose of our study was to compare the bony landmarks of ACL footprint on femur by three-dimensional computed tomography (3D CT) scan and arthroscopy in chronic ACL-deficient knees. Fifty patients above 18 years of age who were diagnosed of having ACL tear were selected for the study. All the cases were more than 6 months old since the injury. Preoperative 3D CT scan of the affected knee was obtained for each of them. They underwent single-bundle anatomic ACL reconstruction. Measurements were done on the preoperative 3D CT and arthroscopy to quantify the position of the LIR and BR. The proximodistal distance of lateral femoral condyle was 21.41+/-2.5 mm on CT scan and 22.02+/-2.02 mm on arthroscopy. On preoperative 3D CT scan, the midpoint of the LIR was found to be located at a mean distance of 11.17±2.11 mm from the proximal margin of the lateral femoral condyle. On arthroscopy, it was at 10.18+/-1.52 mm from the proximal margin the lateral femoral condyle. The "bifurcate ridge"(BR) was not visible in any of the cases during arthroscopy or CT scan. We concluded that LIR is an easily identifiable bony landmark on arthroscopy in all cases. It can also be identified on CT scans. BR is not identified both on arthroscopy and CT scans in chronic ACL tears. The arthroscopic measurements of bony landmarks are quite close to those of CT scan. Midpoint of LIR is at 52.185% of the proximodistal distance on CT scan evaluation and it is at 46.21% on arthroscopic evaluation.

Postoperative medial meniscal shift in the knee-flexed position following meniscal repair associated with anterior cruciate ligament reconstruction

Purpose: The anterior cruciate ligament (ACL) is an important restraint against anterior tibial translation and internal rotation. The ACL injury has a high risk of meniscal injury and cartilage damage that progresses to osteoarthritis of the knee. The medial meniscus (MM) acts as a secondary stabilizer of the anterior tibial translation. Therefore, the MM posterior segment is more susceptible to injury in knees with chronic ACL failure. Compared with the extended position, in the knee-flexed position, the contact area of the tibiofemoral joint is reduced and the contact pressure between the meniscus and the femoral condyle seems to be increased. However, relationships between MM repair concomitant with ACL reconstruction and the postoperative MM translation in the knee-flexed position remains unclear. The aim of this study was to evaluate the positional shift of MM posterior segment at 90° of knee flexion in patients who underwent MM repair associated with ACL reconstruction. Methods: The subjects were 24 patients who had open magnetic resonance imaging (MRI) scans before and after arthroscopic surgery from August 2014 to June 2017. This study included 12 patients who underwent ACL reconstruction without MM tears (no tear group) and 12 patients who underwent ACL reconstruction with MM repair (MM repair group). The shape of MM posterior segment was evaluated using open MRI at 90° of knee flexion before surgery and 3 months postoperatively. MM length (MML), MM posterior body width (MMPBW), MM height (MMH), and MM posterior extrusion (MMPE) were investigated. Differences between groups were assessed using the Mann–Whitney U test. Power and statistical analyses were performed using EZR-WIN software. Significance was set at P < 0.05. Results: In MM repair group, MML decreased from 46.8 ± 3.9 mm to 43.6 ± 3.6 mm (P = 0.01). MMH, MMPBW, and MMPE decreased from 7.2 ± 1.3 mm to 6.8 ± 1.2 mm (P = 0.3), from 14.1 ± 1.6 mm to 11.2 ± 1.6 mm (P < 0.01), and from 4.4 ± 1.6 mm to 1.8 ± 1.1 mm (P < 0.01) after concurrent MM repair with ACL reconstruction, respectively. Compared with no tear group, there were no significant differences in preoperative MML, MMH, and MMPBW. However, preoperative MMPE was significantly higher in MM repair group than in no tear group. On the other hand, no significant differences between two groups were observed in postoperative four parameters. Conclusions: This study demonstrated that the MM posterior segment was compressed and extruded posteriorly by an abnormal anterior tibial translation at 90° of knee flexion in ACL-deficient knees, especially with concomitant MM posterior segment tears. Concurrent MM repair with ACL reconstruction improved an abnormal posterior extrusion of the MM. Our results suggest that simultaneous meniscal repair with ACL reconstruction can decrease excessive posterior shift of the torn MM at the knee-flexed position. The clinical relevance of our study is that the procedure can restore posterior shift of the torn MM and eventually prevent osteoarthritis of the knee.TableNo tear group (n=12)MM tear group (n=12)P value< pre-operation >MML (mm)45.0 ±3.246.8 ±3.90.25MMPW (mm)13.3 ±1.914.1 ±1.70.19MMH (mm)7.5 ±1.17.2 ±1.30.43MMPE (mm)2.0 ± 1.84.4± 1.60.007*< post-operation >MML (mm)43.9 ±3.143.6 ±3.60.62MMPW (mm)12.4 ±2.011.3 ± 1.70.16MMH (mm)7.2 ±1.16.8 ± 1.20.43MMPE (mm)1.4 ±1.31.8 ± 1.10.14*P < 0.05 Open table in a new tab *P < 0.05

Chronicity of Anterior Cruciate Ligament Deficiency, Part 2: Radiographic Predictors of Early Graft Failure.

Background:Accumulating evidence suggests that long-term anterior cruciate ligament (ACL) deficiency can give rise to an abnormal tibiofemoral relationship and subsequent intra-articular lesions. However, the effects of chronic ACL deficiency (ACLD) on early graft failure after anatomic reconstruction remain unclear.Hypothesis:We hypothesized that patients with long-term ACLD lasting more than 5 years would have a greater rate of early graft failure due to insufficient intraoperative reduction of the tibia and that the preoperative and immediately postoperative abnormal tibiofemoral relationship in the sagittal plane, such as anterior tibial subluxation (ATS), would correlate with the graft status on postoperative magnetic resonance imaging (MRI).Study Design:Cohort study; Level of evidence, 3.Methods:A total of 358 patients who had undergone anatomic ACL reconstruction with hamstring grafts were divided into 5 groups based on chronicity of ACLD: (1) 0 to 6 months, (2) 6 months to 1 year, (3) 1 to 2 years, (4) 2 to 5 years, and (5) longer than 5 years. Preoperatively and immediately postoperatively, lateral radiographs in full extension were taken in all patients to evaluate the tibiofemoral relationship, specifically with regard to ATS, space for the ACL (sACL), and extension angle. All patients underwent MRI at 6 months to reveal graft status. Groups with a high rate of graft failure were further analyzed to compare demographic and radiographic factors between the intact and failure subgroups, followed by multivariate logistic regression analysis to identify predisposing factors.Results:Graft failure without trauma was observed in 4 (1.8%), 0 (0%), 1 (3.7%), 3 (9.7%), and 8 patients (17.7%) in groups 1, 2, 3, 4, and 5, respectively. Of the 76 patients in groups 4 and 5, significant differences were noted between the failure and intact subgroups in preoperative ATS (4.9 vs 2.4 mm, respectively; P < .01), side-to-side differences in sACL (sACL-SSD) (4.7 vs 1.9 mm, respectively; P < .01), extension deficit (4.4° vs 1.3°, respectively; P < .01), and chondral lesions (P = .02), while postoperative ATS and sACL-SSD showed no differences. Multivariate logistic regression analysis revealed that of these factors, preoperative sACL-SSD could be a risk factor for early graft failure (odds ratio, 3.2; 95% CI, 1.37-7.46).ConclusionEarly graft failure at 6 months increased in patients with ACLD longer than 2 years. In this population, preoperative sACL-SSD was the most significant risk factor for early graft failure on MRI. However, immediately postoperative radiographic measurements had no effect on graft failure rates.

Association of ACL Laxity Tests with Arthroscopic Findings in Chronic ACL and PCL Deficient Knees.

An anterior cruciate ligament (ACL) injury may be diagnosed by clinical examination and radiological investigation using magnetic resonance imaging or by arthroscopy. 1,2 Based on our experience, the ACL tear in concomitant chronic ACL and posterior cruciate ligament (PCL) deficient knees may produce knee laxity, which is more difficult to assess on clinical examination, which in turn may affect the management algorithm of the patient. Our hypothesis is that, in a concomitant chronic ACL and PCL injury, posterior capsular contracture and abnormal reattachment of torn ACL will result in less clinical and subjective laxity, preoperatively. The aim of this study is to review a cohort of patients who had undergone PCL reconstructive surgery and compare the preoperative clinical assessments with and without anesthesia with arthroscopic finding of ACL. This is to assess the accuracy and reliability of clinical ACL laxity tests in detecting ACL tear in chronic ACL and PCL injury.

Accuracy of the Lever Sign Test in the Diagnosis of Anterior Cruciate Ligament Injuries.

Background:The lever sign test is a new physical examination tool to diagnose anterior cruciate ligament (ACL) tears. Preliminary results suggest almost 100% sensitivity and specificity to diagnose acute and chronic complete ACL tears and clinically significant partial tears as compared with magnetic resonance imaging (MRI).Purpose:To assess the sensitivity and specificity of the lever sign test for the diagnosis of acute ACL injuries, as compared to MRI. We also aimed to determine the accuracy of the lever sign test compared with 3 other tests (anterior drawer, Lachman, and pivot shift) when performed by providers of various training levels, and with the patient awake or under anesthesia.Study Design:Cohort study (diagnosis); Level of evidence, 2.Methods:We evaluated patients with a chief concern of acute (≤4 weeks) knee pain seen between October 2014 and January 2015, with a thorough history, physical examination, and standard radiographs. MRI was the reference standard; patients without an MRI evaluation were excluded. The 4 physical examination maneuvers were performed on each symptomatic knee during the initial clinic visit (for nonsurgical patients) or under anesthesia in the operating room (for surgical patients) by a randomly assigned undergraduate student, medical student, orthopaedic resident, or orthopaedic fellow. The senior author trained all staff to perform the lever sign test. Statistical analyses were performed.Results:Of 102 patients, 54 were surgical (28 female, 26 male), and 48 were nonsurgical (16 female, 32 male); the mean patient age was 23 years (range, 15-66 years). The overall accuracy of the lever sign test was 77% (63% sensitivity, 90% specificity); the accuracy was similar between patients under anesthesia and awake (77% vs 76%, respectively). There were no significant differences when comparing the sensitivity and specificity of the lever sign test with patients under anesthesia and awake (sensitivity: under anesthesia, 86%, and awake, 68% [P = .40]; specificity: under anesthesia, 85%, and awake, 96% [P = .17]). Furthermore, the accuracy of the lever sign test was similar when performed on female versus male patients (75% vs 79%, respectively) or when performed by undergraduate students and medical students compared with orthopaedic residents and fellows (84% vs 88%, respectively).Conclusion:Our study results challenge the exceptional sensitivity and specificity values (both 100%) of the lever sign test, as reported by the original author of the test.

Improvement in the medial meniscus posterior shift following anterior cruciate ligament reconstruction.

Anterior cruciate ligament (ACL) reconstruction can reduce the risk of developing osteoarthritic knees. The goals of ACL reconstruction are to restore knee stability and reduce post-traumatic meniscal tears and cartilage degradation. A chronic ACL insufficiency frequently results in medial meniscus (MM) injury at the posterior segment. How ACL reconstruction can reduce the deformation of the MM posterior segment remains unclear. In this study, we evaluated the form of the MM posterior segment and anterior tibial translation before and after ACL reconstruction using open magnetic resonance imaging (MRI). Seventeen patients who underwent ACL reconstructions without MM injuries were included in this study. MM deformation was evaluated using open MRI before surgery and 3months after surgery. We measured medial meniscal length (MML), medial meniscal height (MMH), medial meniscal posterior body width (MPBW), MM-femoral condyle contact width (M-FCW) and posterior tibiofemoral distance (PTFD) at knee flexion angles of 10° and 90°. There were no significant pre- and postoperative differences during a flexion angle of 10°. At a flexion angle of 90°, MML decreased from 43.7±4.5 to 41.4±4.5mm (P<0.001), MMH from 7.5±1.4 to 6.9±1.4mm (P=0.006), MPBW from 13.1±2.0 to 12.2±1.9mm (P<0.001) and M-FCW from 10.0±1.5 to 8.5±1.5mm (P<0.001) after ACL reconstruction. The PTFD increased from 2.1±2.8 to 2.7±2.4mm after ACL reconstruction (P=0.015). ACL reconstruction affects the contact pattern between the MM posterior segment and medial femoral condyle and can reduce the deformation of the MM posterior segment in the knee-flexed position by reducing abnormal anterior tibial translation. It possibly prevents secondary injury to the MM posterior segment and cartilage that progresses to knee osteoarthritis. IV.

Anterior Cruciate Ligament Tears: Impact of Delayed Presentation on Intra-Articular Injuries

Objectives:Chronic anterior cruciate ligament (ACL) injury is associated with increased risk for meniscal and chondral injuries. The purpose of this study was to examine what intra-articular injuries occur related to the cartilage and meniscus in the setting of chronic ACL deficiency.Methods:A cross-sectional cohort study was conducted using a retrospective chart review for all patients who sustained an ACL injury and underwent reconstruction from January 1, 2009 to May 14, 2015. Demographic variables were age, gender, and BMI (Body Mass Index). Additionally, days from injury to surgery, presence of meniscus tears and presence of articular cartilage injury were recorded. Data was analyzed to determine the association between delay of surgery and cartilage or meniscus injury as well as gender, BMI and age at the time of surgery.Results:410 patients were included in this study. The average age was 27 ± 8.8 years (range of 14-59 years). 58.5% of patients had a BMI >25. 70.5% of the patients were male. 27.3% of patients were treated within 3 months of injury, 23.6% between 3-6 months, 18% between 6-12 months, 24.1% between 12-60 months, and 6.9% >60 months (Table 1). Male gender and older age were significant predictive factors for delaying ACL surgery (P < .01). Male gender was significantly associated with presence of lateral meniscus tear (LMT) (P < .001) and lateral femoral condyle (LFC) injury (P< .01). The 40+ age group was significantly more likely to have an medial femoral condyle (MFC) injury (P < .01), medial tibial plateau (MTP) injury (P < .001), lateral tibial plateau (LTP) injury (P < .01), and patellofemoral (PF) injury (P < .001) as compared to those <20 years old. Patients with BMI >25 were significantly more likely to have an MFC injury (P< .05). There was a significant correlation of medial meniscus tear (MMT) with MFC and MTP injury (P < .001, OR 4.8; P < .05, OR 2.6). There was also a significant correlation of LMT and LTP injury (P < .05, OR 2.0). An increase in the presence of MMT was seen in longer delay to time of surgery (P < .001). When compared to the < 3 months group, the 6 to < 12 months group (OR 2.1), the 12 to < 60 months group (OR 4.2) and the 60 months or greater group (OR 6.2) were more likely to have a MMT. A similar trend was seen with MFC injury (P < .001) in the 6 to < 12 months group (OR 2.7), the 12 to < 60 months group (OR 3.1), and the 60 months or greater group (OR 8.3). Presence of LTP injury and LFC injury was also significantly increased with surgical delay, but this association did not occur until 12 to < 60 months (P < .05; OR 5.6) and 60 months or greater (P < .001; OR 21.5) (Figure 1).Conclusion:Delaying ACL surgery for 6 months or longer is associated with an increased presence of medial meniscus tears and chondral injury (MFC, LFC, and LTP), with increased incidence in longer delays. This data supports not delaying surgery more than 6 months following an ACL tear to prevent the incidence of secondary meniscus tears and articular cartilage injury. In addition, particular attention should be paid to those who are older age and male gender as they are at increased risk for more severe cartilage and meniscal injuries.Table 1.Demographic Factors and Associated Meniscal and Chondral Injuries Identified in Surgerya BMIAge (years)Gender <2525 to <3030+<2020 to <3030 to <4040+MaleFemale MMT 69/138 (50.0)98/167 (58.7)46/73 (63.0)39/77 (50.6)101/187 (54.0)64/104 (61.5)27/40 (67.5) P=NS166/288 (57.6)66/121 (54.5) P=NS LMT 75/138 (54.3)98/167 (58.7)49/73 (67.1) P=NS49/77 (63.6)119/188 (63.3)58/104 (55.8)15/40 (37.5) OR, 0.3 P < 0.5187/289 (64.7) OR, 2.354/121 (44.6) P < .001 MFC Injury 25/138 (18.1)53/167 (31.7) OR, 2.122/73 (30.1) OR, 1.9 P < .0512/77 (15.6)47/188 (25.0)33/104 (31.7) OR, 2.519/40 (47.5) OR, 4.9 P < .0172/289 (24.9)40/121 (33) P=NS LFC Injury 8/138 (5.8)22/167 (13.2)9/73 (12.3) P=NS1/76 (1.3)26/188 (13.8)11/104 (10.6)2/40 (5.0) P=NS35/288 (12.1) OR, 3.25/121 (4.1) P < .05 MTP Injury 2/137 (1.5)12/167 (7.2)5/72 (6.9) P=NS1/76 (1.3)4/187 (2.1)6/104 (5.8)10/40 (25.0) OR, 25.0 P < .00119/288 (6.6)2/118 (1.7) P=NS LTP Injury 13/138 (9.4)20/167 (12.0)11/73 (15.1) P=NS2/76 (2.6)18/188 (9.6)19/104 (18.3) OR, 8.38/40 (20.0) OR, 9.2 P < .0131/288 (10.8)16/121 (13.2) P = NS PF Injury 22/138 (15.9)35/167 (21.0)21/73 (28.8) P=NS5/77 (6.5)17/188 (9.0)35/104 (33.7) OR, 7.325/40 (62.5) OR, 24.0 P < .00155/289 (19)27/121 (22.3) P=NS aValues are expressed as n (%). P < .05 considered statistically significant, OR, odds ratio; NS, not significant, OR listed for groups significantly different from comparison group. Female gender was used as the comparison group for gender.

Outcome of ACL Reconstruction for Chronic ACL Injury in Knees without the Posterior Horn of the Medial Meniscus: Comparison with ACL Reconstructed Knees with An Intact Medial Meniscus.

PurposeCadaveric studies have shown that deficiency of the posterior horn of the medial meniscus (PHMM) increases strain on the anterior cruciate ligament (ACL) graft. However, its influence on the clinical and radiological outcome after ACL reconstruction is less discussed and hence evaluated in this study.Materials and MethodsThis study included 77 cases of ACL reconstruction with a minimum 18-month follow-up. Of the 77 cases, 41 patients with intact menisci were compared clinically and radiologically with 36 patients with an injury to the PHMM that required various grades of meniscectomy. The knees were evaluated using subjective International Knee Documentation Committee (IKDC) score and Orthopadische Arbeitsgruppe Knie (OAK) score.ResultsCases with intact menisci showed better stability (p=0.004) at an average of 44.51 months after surgery. No significant differences were noted in the overall OAK score, subjective IKDC score, and functional OAK score (p=0.082, p=0.526, and p=0.363, respectively). The incidence of radiological osteoarthrosis was significantly higher in the posterior horn deficient knees (p=0.022).ConclusionsThe tendency toward relatively higher objective instability and increased incidence of osteoarthrosis in the group with absent posterior horn reinforces its importance as a secondary stabiliser of the knee.

Passive Anterior Tibial Subluxation in the Setting of Anterior Cruciate Ligament Injuries: A Comparative Analysis of Ligament-Deficient States

Background: Static anterior tibial subluxation after an anterior cruciate ligament (ACL) injury highlights the abnormal relationship between the tibia and femur in patients with ACL insufficiency, although causal factors including injuries to secondary stabilizers or the time from injury to reconstruction have not been examined. Purpose: To determine static relationships between the tibia and femur in patients with various states of ACL deficiency and to identify factors associated with anterior tibial subluxation. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Patients treated for ACL injuries were identified from an institutional registry and assigned to 1 of 4 cohorts: intact ACL, acute ACL disruption, chronic ACL disruption, and failed ACL reconstruction (ACLR). Anterior tibial subluxation of the medial and lateral compartments relative to the femoral condyles were measured on magnetic resonance imaging (MRI), and an MRI evaluation for meniscal tears, chondral defects, and injuries to the anterolateral ligament (ALL) was performed. Results: One hundred eighty-six ACL-insufficient knees met inclusion criteria, with 26 patients without an ACL injury utilized as a control group. In the lateral compartment, the mean anterior tibial subluxation measured 0.78 mm for the control group (n = 26), 2.81 mm for the acute ACL injury group (n = 74), 3.64 mm for the chronic ACL injury group (n = 40), and 4.91 mm for the failed ACLR group (n = 72). In the failed ACLR group, 37.5% of patients demonstrated lateral compartment anterior subluxation ≥6 mm, and 11.1% of this group had anterior subluxation of the lateral compartment ≥10 mm. Multivariate regression revealed that the presence of both medial and lateral chondral defects was associated with a mean 1.09-mm increase in subluxation of the medial compartment (P = .013). The combination of medial and lateral meniscal tears was an independent predictor of increased lateral tibia subluxation by 1.611 mm (P = .0022). Additionally, across all knee states, an injury to the ALL was associated with increased anterior tibial subluxation in both the medial compartment (P = .0438) and lateral compartment (P = .0046). In 29.4% of knees with ALL injuries, lateral tibial subluxation was ≥6 mm, but with multivariate regression analysis, an ALL injury was not an independent predictor of anterior subluxation of the lateral compartment. Conclusion: Knees with failed ACLR are associated with more anterior tibial subluxation than those with primary ACL deficiency. Using previously reported thresholds of 6 to 10 mm of lateral compartment subluxation for a positive pivot shift, between 11.1% and 37.5% of knees with failed ACLR may be in a “resting pivoted position.” In primary ACL-deficient knees, anterior tibial subluxation is associated with chondral injuries and meniscal tears but not injury chronicity.

Unstable osteoarthritis genu varum. Our experience

Background:The natural evolution of chronic anterior cruciate ligament (ACL) failure is the progressive deterioration of articular cartilage of the knee, which consequences are the arthrosis and the secondary misalignment. This is an increasingly common in middle-aged patients (30-50 years). Also, these patients are demanding reinstatement expectation of sporting activity, claiming that refund promptly and at the same level prior to the injury.Objectives:Communicate the experience in our service, of treatment implement in young adults patients with misalignment., osteoarthritis and instability anteroposterior; describe the algorithm used and technique surgical. Study desing: Case study series; level of evidence 3.Methods:Series case study, retrospective. There were 15 valgus osteotomies additive of tibia with plastic ligaments of anterior cruciate ligament (in a same time surgical) in the period between 2014 and 2015.Results:Average monitoring of 8 months. The following parameters were evaluated pre and postoperative: pain (EVA 3.06 / 0.8), instability (Lachman 1.4 / 0.6), Score of Lysholm (83.9 / 108/5), thigh circumference (-0.13 cm / -1.86 cm) and range of motion (flexion and extension).Conclusion:The instability on knees with misalignment, increases progression of osteoarthritis. The presence of pain, misalignment and instability, will guide the therapeutic indication. If we make an indicated process (osteotomy and ACL) in the indicated time and in the indicated patient, we can get as excellent results like in our series, delaying the natural progression of the arthrosis. In this way, we increase the expectations of return to practice recreational sports of our patients.

Preliminary Results in Anatomic All-inside Anterior Cruciate Ligament Reconstruction

Abstract Introduction: Anterior cruciate ligament (ACL) rupture is one of the most common lesions in knee traumatology; therefore the number of ACL reconstructions is increasing worldwide. Usually, an anteromedial (AM) accessory portal is required in anatomical positioning of the femoral tunnel, which is not absolutely necessary in this technique. Aim: Assessment of all-inside ACL reconstruction preliminary clinical results with adjustable loops and buttons on both femoral and tibial surfaces. Method: Our prospective study included 28 subjects (19 male, 9 female) with chronic ACL ruptures. The mean age of the study population was 27.72 ± 8.23 years. In all cases ACL reconstruction was carried out with the use of quadrupled semitendinosus auto-grafts with adjustable loops and buttons on the femoral and tibial surfaces and anatomic placement of both tunnels, using an outside-in technique, with flipcutters (Arthrex®). Clinical and radiological evaluations were carried out before surgery and at 3 and 6 months postoperatively, with the Lysholm scoring system, the Tegner activity scale and anterior-posterior and latero-lateral X-rays. Anterior knee laxity was measured in 25° of flexion using a portable arthrometer (RolimeterTM, Aircast®) and maximum manual force. Results: During the final follow-up, the Lysholm score was good and excellent in 27 cases, with a mean Lysholm score of 95.55 ± 4.63; all results were classified as good. The mean preoperative Tegner activity score was 3.46 ± 1.71 (range: 1-7), and the post-operative mean score was 5.75 ± 2.24 (range: 2-10). We found no graft ruptures. Preoperative knee laxity measurements showed a mean displacement of 11.5 ± 3.1 mm and side-to-side differences of 5.6 ± 3.5 mm, while the postoperative measurements at the last follow-up were 6.3 ± 1.54 mm and 2.65 ± 1.86 mm, respectively. Conclusion: Short-term clinical outcomes of all-inside ACL restoration with anatomic placement femoral and tibial tunnels seem to recommend this surgical option, with good subjective and objective results. Additional research will have to prove the long-term success.

Arthroscopic refixation of acute proximal anterior cruciate ligament rupture using suture anchors

Arthroscopic assisted suture anchor refixation combined with microfracturing of the femoral ACL insertion zone in cases of acute proximal anterior cruciate ligament (ACL) rupture to restore anatomical and biomechanical properties of the native ACL. Acute proximal ACL rupture/avulsion, multiligament injury of the knee CONTRAINDICATIONS: Chronic (>6weeks) proximal ACL rupture, intraligamentary rupture, as well as previous ACL surgery. Arthroscopic examination of the knee joint, debridement of the femoral insertion zone, examination of the ligament quality by aprobe, insertion of acurved lasso through the ACL to place the sutures and use of adrill guide to place the anchor in the middle of the femoral ACL insertion. Microfracturing holes around the femoral footprint were made by an awl to enhance healing properties of the ACL. Partial weight bearing was permitted and crutches were used for 6weeks, knee brace limited for the first 2weeks 0‑0-0°, then 0‑0-90° for the following 4weeks. Atotal of 20patients who underwent acute proximal ACL suture anchor refixation were evaluated after amean follow-up of 28months. Regarding stability, mean values of the KT-1000 arthrometer indicated stable results (<3mm), 3patients had a1+ Lachman and 4patients had a1+ pivot shift. IKDC (International Knee Documentation Committee) score indicated that 17 cases were very good to good (12A, 4B) and in 3 cases the results were satisfactory (3C). Magnetic resonance imaging showed that the ALC was found to be intact in 17cases. The total rate of revision was 15 % (3/20) because of recurrent instability.

ACL Deficiency Increases Forces on the Medial Femoral Condyle and the Lateral Meniscus with Applied Rotatory Loads.

The articular surfaces and menisci act with the anterior cruciate ligament (ACL) to stabilize the knee joint. Their role in resisting applied rotatory loads characteristic of instability events is unclear despite commonly observed damage to these intra-articular structures in the acute and chronic ACL injury settings. Ten fresh-frozen human cadaveric knees were mounted to a robotic manipulator. Combined valgus and internal rotation torques were applied in the presence and absence of a 300-N compressive load. Forces carried by the individual menisci and via cartilage-to-cartilage contact on each femoral condyle in ACL-intact and ACL-sectioned states were measured using the principle of superposition. In response to applied valgus and internal rotation torques in the absence of compression, sectioning of the ACL increased the net force carried by the lateral meniscus by at most 65.8 N (p < 0.001). Moreover, the anterior shear force carried by the lateral meniscus increased by 25.7 N (p < 0.001) and 36.5 N (p = 0.042) in the absence and presence of compression, respectively. In response to applied valgus and internal rotation torques, sectioning of the ACL increased the net force carried by cartilage-to-cartilage contact on the medial femoral condyle by at most 38.9 N (p = 0.006) and 46.7 N (p = 0.040) in the absence and presence of compression, respectively. Additionally, the lateral shear force carried by cartilage-to-cartilage contact on the medial femoral condyle increased by at most 21.0 N (p = 0.005) and by 28.0 N (p = 0.025) in the absence and presence of compression, respectively. Forces carried by the medial meniscus and by cartilage-to-cartilage contact on the lateral femoral condyle changed by <5 N as a result of ACL sectioning. ACL sectioning increased the net forces carried by the lateral meniscus and medial femoral condyle-and the anterior shear and lateral shear forces, respectively-in response to multiplanar valgus and internal rotation torque. These loading patterns provide a biomechanical rationale for clinical patterns of intra-articular derangement such as lateral meniscal injury and osseous remodeling of the medial compartment seen with ACL insufficiency.

Atypical presentation of intra-articular osteochondroma of knee in adolescent- case report

&lt;p&gt;Osteochondroma is most common benign bone tumor around knee joint. They occur during the period of growth, grows away from joint line and rarely responsible for mechanical symptoms. This paper reports a rare presentation of intra-articular osteochondroma in knee with mechanical instability symptoms, mild to moderate pain and swelling of knee joint. Patient was 20 years old male and misdiagnosed as chronic nonspecific synovitis, tubercular arthritis and anterior cruciate ligament tear of knee. We assessed him clinically and radiologically and diagnosis was established based on MRI and arthroscopy. He was treated by open excision of tumor, and patients recover uneventfully. Instability of knee joint in this case can be attributed due to rough surface of osteochondroma just beneath lower attachment of patellar tendon.&lt;/p&gt;

Medial Opening Wedge Proximal Tibial Osteotomy

Genu varus malalignment can lead to medial compartment overload and progression of ipsilateral compartment osteoarthritis. To slow this process, a medial opening wedge proximal tibial osteotomy (PTO) can be performed. This type of PTO is indicated in patients with genu varus malalignment and isolated medial compartment osteoarthritis of the knee, prior to or concurrent with medial compartment cartilage procedures or meniscal transplants, chronic posterolateral corner deficiency, or chronic anterior cruciate ligament deficiency. When treating ligamentous instability, a PTO can be performed in isolation, with simultaneous ligament reconstruction, or as a staged procedure with the osteotomy first, followed by ligament reconstruction if instability persists. Failure to address malalignment in cases of concurrent ligament reconstruction leads to increased stress on the graft and potential graft failure. One distinct advantage of this procedure is the ability to correct deformities in the sagittal and coronal planes. The purpose of this article was to describe our technique used to perform a medial opening wedge PTO.

Comparison Between Single- and Double-Bundle Anterior Cruciate Ligament Reconstruction With 6- to 8-Stranded Hamstring Autograft

Background: Whether double-bundle (DB) anterior cruciate ligament (ACL) reconstruction with 6- to 8-stranded hamstring autograft (HG) is better than single-bundle (SB) ACL reconstruction remains debatable, as long-term follow-up data are lacking. Purpose: To prospectively investigate and compare the long-term results of DB and SB ACL reconstruction with a 6- to 8-stranded HG. Study Design: Randomized controlled clinical trial; Level of evidence: 1. Methods: A total of 80 patients with chronic ACL rupture were randomized to SB or DB ACL reconstruction with a 6- to 8-stranded HG. In the SB group, both the semitendinosus tendon (ST) and the gracilis tendon (GT) were prepared in 3 or 4 strands, with a total of 6 to 8 strands. In the DB group, the ST was prepared in 3 or 4 strands used for the anteromedial bundle, and the GT was prepared in the same manner for the posterolateral bundle. Each graft was fixed with an EndoButton, a bioabsorbable interference screw, and a staple. Outcome assessment was performed by a blinded independent observer using International Knee Documentation Committee (IKDC), Tegner, and Lysholm scores, as well as range of motion (ROM), Lachman test, pivot-shift test, KT-2000 arthrometer side-to-side difference, and return-to-sport data. Results: A total of 68 patients (DB group, 34; SB group, 34) were observed for a mean of 80 months (range, 74-86 months). There were 2 traumatic instability failures and two 5° extension restrictions in the DB group, while no failures or 5° extension restrictions were observed in the SB group. The mean Lysholm, Tegner, and IKDC scores improved significantly in both groups compared with preoperation scores (P < .05). No patient had a positive Lachman test result. No significant differences were found between groups in functional scores, incidence of pivot shift, ROM, Lachman test, KT-2000 arthrometer anterior laxity, or time and level of return to sport. Conclusion: Both SB and DB ACL reconstruction with 6- to 8-stranded HG showed satisfactory results in subjective scores and anteroposterior and rotational stability over a nearly 7-year follow-up; neither technique was superior.