scholarly journals A Novel Implant System for Unloading the Medial Compartment of the Knee by Lateral Displacement of the Iliotibial Band

2017 ◽  
Vol 5 (3) ◽  
pp. 232596711769361 ◽  
Author(s):  
Vivek N. Shenoy ◽  
Hanson S. Gifford ◽  
John T. Kao
Keyword(s):  
Mechanical Load ◽  
Early Stage ◽  
Lateral Displacement ◽  
Femoral Condyle ◽  
Lateral Compartment ◽  
Medial Compartment ◽  
Iliotibial Band ◽  
Moment Arm ◽  
Treatment Gap ◽  
Medial Knee

Background: Medial knee osteoarthritis (OA) typically occurs with excessive mechanical load within the medial compartment, resulting in degeneration of the articular cartilage. Purpose: A novel extracapsular implant (Latella Knee Implant) has been developed to unload the medial compartment of the knee. The implant displaces the iliotibial band (ITB) over the lateral femoral condyle, thereby increasing its effective moment arm, resulting in a transfer of load from the medial compartment to the lateral compartment of the knee. A cadaveric study was performed to evaluate the effect of altering the moment arm of the ITB on knee biomechanics. Study Design: Controlled laboratory study. Methods: A 6-degrees-of-freedom robotic testing system was utilized to measure medial and lateral compartment loads in 8 fresh-frozen cadaveric knees at various ITB loads and knee flexion angles. Measurements were made with and without the implant in place. The system measured the compartment forces at flexion angles between 0° and 30° under 3 simulated loading conditions (300 N quadriceps, 100 N hamstrings, and [1] 0 N ITB, [2] 50 N ITB, [3] 100 N ITB). Results: Lateral displacement of the ITB between 15 and 20 mm resulted in medial compartment unloading between 34% and 65%. Conclusion: Unloading the medial compartment with this novel implant has the potential to address the treatment gap for patients with medial knee OA. Clinical Relevance: Currently, there exists a treatment gap for patients with medial compartment OA who have exhausted conservative management but whose disease and symptoms do not warrant more invasive surgical procedures. An extracapsular implant to unload the medial compartment could fill this treatment gap by providing patients and surgeons with a less invasive option for early to mid-stage OA. Unloading the medial compartment may alleviate pain and improve function, allowing patients with early-stage medial OA to remain active longer prior to considering more invasive options such as arthroplasty.

scholarly journals Extra excitation of biceps femoris during neuromuscular electrical stimulation reduces knee medial loading

2019 ◽  
Vol 6 (3) ◽  
pp. 181545 ◽  
Author(s):  
Rui Xu ◽  
Dong Ming ◽  
Ziyun Ding ◽  
Anthony M. J. Bull
Keyword(s):  
Electrical Stimulation ◽  
Knee Joint ◽  
Neuromuscular Electrical Stimulation ◽  
Biceps Femoris ◽  
Step Length ◽  
Lateral Compartment ◽  
Medial Compartment ◽  
Medial Knee ◽  
Before And After ◽  
Reaction Forces

Medial knee joint osteoarthritis (OA) is a debilitating and prevalent condition. Surgical treatment consists of redistributing the forces from the medial to the lateral compartment through osteotomy, or replacing the joint surfaces. As the mediolateral load distribution is related to the action of the musculature around the knee, the aim of this study was to devise a technique to redistribute these forces non-surgically through changes in muscle excitation. Eight healthy subjects participated in the experiment, and neuromuscular electrical stimulation was used to change the muscle forces around the knee. A musculoskeletal model was used to quantify the loading on the medial compartment of the knee, and a novel algorithm devised and implemented to simulate neuromuscular electrical stimulation. The forces and moments at the knee, ground reaction forces, walking velocity and step length were quantified before and after stimulation. Stimulation of the biceps femoris resulted in a significant decrease in the second peak of the medial knee joint loading by up to 0.17 body weight ( p = 0.016). Kinematic parameters were not significantly affected. Neuromuscular electrical stimulation can decrease the peak loads on the medial compartment of the knee, and thus offers a promising therapy for medial knee joint OA.

Post-Run T2 Mapping Changes in Knees of Adolescent Basketball Players

Cartilage ◽  
2021 ◽  
pp. 194760352110218
Author(s):  
Yigal Chechik ◽  
Eran Beit Ner ◽  
Oleg Lysyy ◽  
Sigal Tal ◽  
Neta Stern ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
T2 Mapping ◽  
Femoral Condyle ◽  
Weight Bearing ◽  
Lateral Compartment ◽  
Medial Compartment ◽  
Cartilage Defects ◽  
Mri Scan ◽  
Basketball Players ◽  
Mean Values

Objective: While articular cartilage defects are common incidental findings among adult athletes, the effect of running on the cartilage of adolescent athletes have rarely been assessed. This study aims to assess the variations in the articular cartilage of the knees in healthy adolescent basketball players using quantitative T2 MRI (magnetic resonance imaging). Design: Fifteen adolescent basketball players were recruited (13.8 ± 0.5 years old). Girls were excluded to avoid potential gender-related confounding effects. Players underwent a pre-run MRI scan of both knees. All participants performed a 30-minute run on a treadmill. Within 15 minutes after completion of their run, players underwent a second, post-run MRI scan. Quantitative T2 maps were generated using the echo modulation curve (EMC) algorithm. Pre-run scans and post-run scans were compared using paired t test. Results: Participants finished their 30-minute run with a mean running distance of 5.77 ± 0.42 km. Pre-run scans analysis found statistically significant ( P < 0.05) changes in 3 regions of the knee lateral compartment representing the cartilaginous tissue. No differences were found in the knee medial compartment. Post-run analysis showed lower T2 values in the medial compartment compared to the pre-run scans in several weight-bearing regions: femoral condyle central (pre/post mean values of 33.9/32.2 ms, P = 0.020); femoral condyle posterior (38.1/36.8 ms, P = 0.038); and tibial plateau posterior (34.1/31.0 ms, P < 0.001). The lateral regions did not show any significant changes. Conclusions: Running leads to microstructural changes in the articular cartilage in several weight-bearing areas of the medial compartment, both in the femoral and the tibial cartilage.

scholarly journals A Simulation Case Study of Knee Joint Compressive Stress during the Stance Phase in Severe Knee Osteoarthritis Using Finite Element Method

Medicina ◽  
2021 ◽  
Vol 57 (6) ◽  
pp. 550
Author(s):  
Takashi Fukaya ◽  
Hirotaka Mutsuzaki ◽  
Toshiyuki Aoyama ◽  
Kunihiro Watanabe ◽  
Koichi Mori
Keyword(s):  
Computed Tomography ◽  
Finite Element Method ◽  
Finite Element ◽  
Knee Joint ◽  
Knee Osteoarthritis ◽  
Compressive Stress ◽  
Mechanical Load ◽  
Medial Compartment ◽  
Medial Knee ◽  
Medial Knee Osteoarthritis

Background and Objectives: Medial knee osteoarthritis is known to increase the mechanical load on the medial compartment of the knee joint during walking; however, it is not visually understood how much the mechanical load increases nor where in the medial compartment of the knee joint that load is focused. Therefore, we conducted a simulation study to determine the location and amount of the mechanical load in the medial compartment of the knee joint during the stance phase. Materials and Methods: Subject was a patient with right medial knee osteoarthritis. Computed tomography imaging and gait analysis were performed on subject. The CT image of the right knee was calculated using finite element analysis software. Since this software can set the flexion angle arbitrarily while maintaining the nonuniform material properties of the bone region, the model is constructed by matching the knee joint extension image obtained by CT to the loading response phase of gait analysis. The data of muscle exertion tension and vertical ground reaction force were inserted into the knee joint model created from the computed tomography-based finite element method, and the knee joint compressive stress was calculated. Results: With regard to compressive stress, the tibia showed high stress at 4.10 to 5.36 N/mm2. The femur showed high stress at 4.00 to 6.48 N/mm2. The joint compressive stress on the medial compartment of the knee joint was found to concentrate on the edge of the medial tibial condyle in the medial knee osteoarthritis subject. Conclusions: The measurement method of knee joint compressive stress by computed tomography-based finite element method can visually be a reliable method of measuring joint compressive stress in the medial knee osteoarthritis. This reflects the clinical findings because concentration of stress on the medial knee joint was observed at the medial osteophyte.

Regional Cartilage Thinning Occurs First in the Walking Weight Bearing Regions of the Femur in Medial Compartment Knee Osteoarthritis

2008 ◽  
Author(s):  
Jennifer C. Erhart ◽  
Anne Mündermann ◽  
Seungbum Koo ◽  
Ben Merrick ◽  
Andrew Deagon ◽  
...  
Keyword(s):  
Knee Osteoarthritis ◽  
Femoral Condyle ◽  
Weight Bearing ◽  
Lateral Compartment ◽  
Medial Compartment ◽  
Treatment Interventions ◽  
Knee Oa ◽  
Highest Weight ◽  
Kellgren And Lawrence ◽  
New Treatment

Osteoarthritis (OA) of the knee affects an estimated 20–40% of individuals over the age of 65 [1], and is nearly 10 times more common in the medial compartment than the lateral compartment [2]. Plain radiography measurements using the Kellgren and Lawrence (KL) scale have been the gold standard for diagnosis of knee osteoarthritis [3]. However, for new treatment interventions for medial compartment knee OA such as load modifying footwear, it would be important to know if the disease-related cartilage loss in the medial compartment occurs initially and predominantly in regions that are weight bearing during walking. Because walking results in highest weight bearing occurring in the anterior and middle regions of the femoral condyle and the anterior region of the tibial plateau, seeing a pattern of thinning in these areas would suggest that walking is an important activity for understanding both the cause and treatment of osteoarthritis.

Biomechanical Comparison of Kinematic and Mechanical Knee Alignment Techniques in a Computer Simulation Medial Pivot Total Knee Arthroplasty Model

2021 ◽  
Author(s):  
Young Dong Song ◽  
Shinichiro Nakamura ◽  
Shinichi Kuriyama ◽  
Kohei Nishitani ◽  
Hiromu Ito ◽  
...  
Keyword(s):  
Femoral Component ◽  
Knee Flexion ◽  
External Rotation ◽  
Knee Kinematics ◽  
Lateral Compartment ◽  
Contact Stresses ◽  
Contact Forces ◽  
Medial Compartment ◽  
Tibial Insert ◽  
Medial Pivot

AbstractSeveral concepts may be used to restore normal knee kinematics after total knee arthroplasty. One is a kinematically aligned (KA) technique, which restores the native joint line and limb alignment, and the other is the use of a medial pivot knee (MPK) design, with a ball and socket joint in the medial compartment. This study aimed to compare motions, contact forces, and contact stress between mechanically aligned (MA) and KA (medial tilt 3° [KA3] and 5° [KA5]) models in MPK. An MPK design was virtually implanted with MA, KA3, and KA5 in a validated musculoskeletal computer model of a healthy knee, and the simulation of motion and contact forces was implemented. Anteroposterior (AP) positions, mediolateral positions, external rotation angles of the femoral component relative to the tibial insert, and tibiofemoral contact forces were evaluated at different knee flexion angles. Contact stresses on the tibial insert were calculated using finite element analysis. The AP position at the medial compartment was consistent for all models. From 0° to 120°, the femoral component in KA models showed larger posterior movement at the lateral compartment (0.3, 6.8, and 17.7 mm in MA, KA3, and KA5 models, respectively) and larger external rotation (4.2°, 12.0°, and 16.8° in the MA, KA3, and KA5 models, respectively) relative to the tibial component. Concerning the mediolateral position of the femoral component, the KA5 model was positioned more medially. The contact forces at the lateral compartment of all models were larger than those at the medial compartment at >60° of knee flexion. The peak contact stresses on the tibiofemoral joint at 90° and 120° of knee flexion were higher in the KA models. However, the peak contact stresses of the KA models at every flexion angle were <20 MPa. The KA technique in MPK can successfully achieve near-normal knee kinematics; however, there may be a concern for higher contact stresses on the tibial insert.

An In Vitro Osteotomy Method to Expose the Medial Compartment of the Human Knee

1997 ◽  
Vol 119 (4) ◽  
pp. 379-385 ◽  
Author(s):  
T. A. Martens ◽  
M. L. Hull ◽  
S. M. Howell
Keyword(s):  
Contact Pressure ◽  
Pressure Measurement ◽  
Femoral Condyle ◽  
Compressive Load ◽  
Medial Femoral Condyle ◽  
Medial Compartment ◽  
New Method ◽  
Load Bearing ◽  
Coronary Ligament

This study was conducted to validate a new in vitro method to expose the medial compartment of the knee to be used in subsequent studies aimed at examining the load bearing capabilities of medial meniscal allografts. The new method involves an osteotomy and reattachment of the medial femoral condyle. The primary hypothesis was that the new method does not alter tibio-femoral contact pressure and area. To validate this method, the baseline contact pressure of the intact medial compartment was measured using a new nondestructive procedure for inserting pressure measurement film into the intact medial hemijoint. A secondary and related hypothesis was that incising the coronary ligament, a destructive method used by previous investigators to position pressure measurement film, alters the normal tibio-femoral contact pressure. To test these hypotheses, Fuji Prescale pressure-sensitive film was used to measure both tibio-femoral contact pressure and area within the medial compartment of the (1) intact knee, (2) the knee after osteotomizing and reattaching the medial femoral condyle, and (3) the osteotomized knee with an incised coronary ligament, using seven cadaver specimens. Measurements were taken at a compressive load of approximately two times body weight with the knee in 0, 15, 30, 45 deg of flexion. No significant differences between the intact and osteotomized knee were detected. Likewise, no significant differences were observed between the osteotomized knee and the osteotomized knee with an incised coronary ligament. These results confirm the utility of the new method in exposing the medial compartment for manipulation and placement of medial meniscal allografts in future studies examining the load-bearing characteristics of meniscal allografts.

scholarly journals Tissue Modification of the Lateral Compartment of the Tibio-Femoral Joint Following In Vivo Varus Loading in the Rat

2012 ◽  
Vol 134 (10) ◽  
Author(s):  
M. L. Roemhildt ◽  
B. D. Beynnon ◽  
M. Gardner-Morse ◽  
K. Anderson ◽  
G. J. Badger
Keyword(s):  
Articular Cartilage ◽  
Subchondral Bone ◽  
Compressive Loading ◽  
Compressive Load ◽  
Lateral Compartment ◽  
Peripheral Region ◽  
Degenerative Changes ◽  
Medial Compartment ◽  
Compressive Loads

This study describes the first application of a varus loading device (VLD) to the rat hind limb to study the role of sustained altered compressive loading and its relationship to the initiation of degenerative changes to the tibio-femoral joint. The VLD applies decreased compressive load to the lateral compartment and increased compressive load to the medial compartment of the tibio-femoral joint in a controlled manner. Mature rats were randomized into one of three groups: unoperated control, 0% (sham), or 80% body weight (BW). Devices were attached to an animal’s leg to deliver altered loads of 0% and 80% BW to the experimental knee for 12 weeks. Compartment-specific material properties of the tibial cartilage and subchondral bone were determined using indentation tests. Articular cartilage, calcified cartilage, and subchondral bone thicknesses, articular cartilage cellularity, and degeneration score were determined histologically. Joint tissues were sensitive to 12 weeks of decreased compressive loading in the lateral compartment with articular cartilage thickness decreased in the peripheral region, subchondral bone thickness increased, and cellularity of the midline region decreased in the 80% BW group as compared to the 0% BW group. The medial compartment revealed trends for diminished cellularity and aggregate modulus with increased loading. The rat-VLD model provides a new system to evaluate altered quantified levels of chronic in vivo loading without disruption of the joint capsule while maintaining full use of the knee. These results reveal a greater sensitivity of tissue parameters to decreased loading versus increased loading of 80% BW for 12 weeks in the rat. This model will allow future mechanistic studies that focus on the initiation and progression of degenerative changes with increased exposure in both magnitude and time to altered compressive loads.

The Lateral Side

2015 ◽  
Author(s):  
John Goodfellow ◽  
John O'Connor ◽  
Hemant Pandit ◽  
Christopher Dodd ◽  
David Murray
Keyword(s):  
Rare Disease ◽  
Surgical Techniques ◽  
Lateral Compartment ◽  
Clinical Results ◽  
Medial Compartment ◽  
Lateral Side ◽  
Normal Anatomy ◽  
Valgus Stress ◽  
Pathological Lesions ◽  
As If

Lateral unicompartmental OA is a relatively rare disease said to account for about one eighth of all unicompartmental arthritis 1 . However, the incidence may be higher because it is a disease of flexion and is commonly missed on standing AP radiographs. To identify lateral OA reliably, either a valgus stress radiograph in 45° flexion or a Rosenberg view is necessary. The clinical results of UKA in the lateral compartment have sometimes been worse than in the medial compartment 2 and sometimes better 3 . Some early papers reported results of series containing both medial and lateral operations as if they were essentially the same, but the normal anatomy and the pathological lesions of the two compartments are very different so the surgical techniques are different.

Correlations between radiological classification systems and confirmed cartilage loss in severe knee osteoarthritis

2020 ◽  
Vol 102-B (3) ◽  
pp. 301-309 ◽  
Author(s):  
Oisin J. F. Keenan ◽  
George Holland ◽  
Julian F. Maempel ◽  
John F. Keating ◽  
Chloe E. H. Scott
Keyword(s):  
Knee Osteoarthritis ◽  
Correlation Coefficient ◽  
Interobserver Reliability ◽  
Severe Disease ◽  
Intraclass Correlation ◽  
Lateral Compartment ◽  
Classification Systems ◽  
Medial Compartment ◽  
Cartilage Loss ◽  
Radiological Classification

Aims Although knee osteoarthritis (OA) is diagnosed and monitored radiologically, actual full-thickness cartilage loss (FTCL) has rarely been correlated with radiological classification. This study aims to analyze which classification system correlates best with FTCL and to assess their reliability. Methods A prospective study of 300 consecutive patients undergoing unilateral total knee arthroplasty (TKA) for OA (mean age 69 years (44 to 91; standard deviation (SD) 9.5), 178 (59%) female). Two blinded examiners independently graded preoperative radiographs using five common systems: Kellgren-Lawrence (KL); International Knee Documentation Committee (IKDC); Fairbank; Brandt; and Ahlbäck. Interobserver agreement was assessed using the intraclass correlation coefficient (ICC). Intraoperatively, anterior cruciate ligament (ACL) status and the presence of FTCL in 16 regions of interest were recorded. Radiological classification and FTCL were correlated using the Spearman correlation coefficient. Results Knees had a mean of 6.8 regions of FTCL (SD 3.1), most common medially. The commonest patterns of FTCL were medial ± patellofemoral (143/300, 48%) and tricompartmental (89/300, 30%). ACL status was associated with pattern of FTCL (p = 0.023). All radiological classification systems demonstrated moderate ICC, but this was highest for the IKDC: whole knee 0.68 (95% confidence interval (CI) 0.60 to 0.74); medial compartment 0.84 (95% CI 0.80 to 0.87); and lateral compartment 0.79 (95% CI 0.73 to 0.83). Correlation with actual FTCL was strongest for Ahlbäck (Spearman rho 0.27 to 0.39) and KL (0.30 to 0.33) systems, although all systems demonstrated medium correlation. The Ahlbäck score was the most discriminating in severe knee OA. Osteophyte presence in the medial compartment had high positive predictive value (PPV) for FTCL, but not in the lateral compartment. Conclusion The Ahlbäck and KL systems had the highest correlation with confirmed cartilage loss at TKA. However, the IKDC system displayed the best interobserver reliability, with favourable correlation with FTCL in medial and lateral compartments, although it was less discriminating in more severe disease. Cite this article: Bone Joint J 2020;102-B(3):301–309

scholarly journals Osteochondritis Dissecans of the Tibial Plateau in Children and Adolescents: A Case Series

2020 ◽  
Vol 8 (8) ◽  
pp. 232596712094138
Author(s):  
Millicent Croman ◽  
Dennis E. Kramer ◽  
Benton E. Heyworth ◽  
Mininder S. Kocher ◽  
Lyle J. Micheli ◽  
...  
Keyword(s):  
Osteochondritis Dissecans ◽  
Tibial Plateau ◽  
Femoral Condyle ◽  
Young Patients ◽  
Case Series ◽  
Lateral Compartment ◽  
Nonoperative Treatment ◽  
Lateral Side ◽  
Level Of Evidence ◽  
Presenting Symptoms

Background: Osteochondritis dissecans (OCD) of the knee is a relatively well-known condition, most commonly arising in the femoral condyle. Lesions arising in the tibial plateau are rarely described. Purpose: To present a case series of OCD lesions of the tibial plateau. Study Design: Case series; Level of evidence, 4. Methods: Medical records and diagnostic imaging of patients <20 years of age with confirmed diagnosis of OCD of the tibial plateau from a single institution were retrospectively reviewed. Characteristic and radiographic features as well as details of both nonoperative and surgical management were investigated. Lesion characteristics and treatment outcomes were also analyzed. Results: A total of 9 lesions were identified in 9 patients (5 females, 4 males) who fit the inclusion criteria. The mean age at diagnosis was 14.2 years (range, 9-17 years). Knee pain (8/9) of longer than 1 year in duration was the most common presenting symptom. All 9 lesions were located on the lateral tibial plateau, and concomitant lateral compartment pathology was present in 5 of 9 patients (4 lateral femoral condyle OCDs, 3 lateral meniscal tears [1 discoid], and 1 discoid meniscus). Only 2 lesions were visible on initial radiographs; all 9 were visible on magnetic resonance imaging. All patients underwent initial nonoperative treatment; 2 patients demonstrated resolution of symptoms. Two patients underwent surgery for concomitant pathology, and the OCD was not addressed surgically. A total of 5 patients continued to be symptomatic after nonoperative treatment, prompting surgical intervention, which consisted of microfracture and chondroplasty in all 5 cases. A total of 2 of the 5 microfracture patients had resolution of symptoms, while another 2 patients had continued symptoms ultimately responsive to steroid injection treatment. One patient had revision microfracture, followed by autologous chondrocyte implantation and an arthroscopic lysis of adhesions. At final follow-up, ranging from 7 months to 10 years, 8 patients were asymptomatic, while 1 patient had developed early osteoarthritis. Conclusion: OCD of the tibial plateau in young patients is rare, usually involves the lateral side, and may have significant long-term implications for knee function. Presenting symptoms are often vague, and lesions may not always be visible on initial radiographs, which may lead to delayed treatment and adversely affect outcomes.

Sign in / Sign up

Export Citation Format

Share Document