scholarly journals Torn ACL: A New Bioengineered Substitute Brought from the Laboratory to the Knee Joint

2004 ◽  
Vol 1 (2) ◽  
pp. 115-121 ◽  
Author(s):  
Francine Goulet ◽  
Denis Rancourt ◽  
Réjean Cloutier ◽  
Pierrot Tremblay ◽  
Anne-Marie Belzil ◽  
...  

Anterior cruciate ligament (ACL) injuries occur at an annual rate of 120 000 in the USA, and many need reconstructive surgery. We report successful results at 1–13 months following implantation of bioengineered ACL (bACL) in goats. A bACL has been developed using autologous ACL cells, a collagen matrix and bone plugs. The extremities of the bACL were fully integrated into the femur and tibia of the host. Vascularisation of the grafts was extensive 1 month post-surgery and improved with time. At 6 months post-grafting, histological and ultrastructural observations demonstrated a highly organised ligamentous structure, rich in type I collagen fibres and fibroblasts. At the implants' insertion sites, characteristic fibrocartilage was observed having well aligned chondrocytes and collagen fibrils. After a year, mechanical rupture of the grafts demonstrated a major gain in strength. Eventual applications of this new technology in humans include multiple uses in orthopaedic, dental and reconstructive surgeries.

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Sean Mc Millan ◽  
Danielle Thorn ◽  
Elizabeth Ford

Background. Anterior cruciate ligament reconstruction (ACLR) is one of the most common lower extremity orthopedic surgeries performed in the United States. Annually, between 100,000 and 200,000 ACL tears affect 1 in 3,000 people. The selection of autograft versus allograft for ACLR has been widely discussed in terms of risk of graft failure. Allograft reconstructions have been shown to have higher rerupture rates. One factor contributing to this risk is delayed biologic graft incorporation. Methods. A retrospective review was performed examining 14 patients who underwent an augmented quadruple-stranded hamstring allograft ACLR with a type I resorbable collagen matrix impregnated with platelet-rich plasma (PRP). Results. Within our clinical practice, the augmentation of quadruple-stranded hamstring allograft ACLR with a type I resorbable matrix impregnated with PRP has yielded good early clinical success at 2-year outcomes ( N = 14 ). Zero ACLR failures have been reported to date in this series. Conclusion. This case series offers a novel approach for soft tissue allograft ACLR augmented with a type I collagen matrix impregnated with PRP. The authors theorize that this augmentation may improve biologic graft incorporation into the host bone tunnels.


Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 877
Author(s):  
Ingrid Zahn ◽  
Daniel David Stöbener ◽  
Marie Weinhart ◽  
Clemens Gögele ◽  
Annette Breier ◽  
...  

Anterior cruciate ligament (ACL) cell sheets combined with biomechanically competent scaffolds might facilitate ACL tissue engineering. Since thermoresponsive polymers allow a rapid enzyme-free detachment of cell sheets, we evaluated the applicability of a thermoresponsive poly(glycidyl ether) (PGE) coating for cruciate ligamentocyte sheet formation and its influence on ligamentocyte phenotype during sheet-mediated colonization of embroidered scaffolds. Ligamentocytes were seeded on surfaces either coated with PGE or without coating. Detached ligamentocyte sheets were cultured separately or wrapped around an embroidered scaffold made of polylactide acid (PLA) and poly(lactic-co-ε-caprolactone) (P(LA-CL)) threads functionalized by gas-phase fluorination and with collagen foam. Ligamentocyte viability, protein and gene expression were determined in sheets detached from surfaces with or without PGE coating, scaffolds seeded with sheets from PGE-coated plates and the respective monolayers. Stable and vital ligamentocyte sheets could be produced within 24 h with both surfaces, but more rapidly with PGE coating. PGE did not affect ligamentocyte phenotype. Scaffolds could be colonized with sheets associated with high cell survival, stable gene expression of ligament-related type I collagen, decorin, tenascin C and Mohawk after 14 d and extracellular matrix (ECM) deposition. PGE coating facilitates ligamentocyte sheet formation, and sheets colonizing the scaffolds displayed a ligament-related phenotype.


2021 ◽  
Vol 9 (10_suppl5) ◽  
pp. 2325967121S0030
Author(s):  
Joseph Tramer ◽  
Lafi Khalil ◽  
Alexander Ziedas ◽  
Muhammad Abbas ◽  
Nima Mehran ◽  
...  

Objectives: The incidence of ACL injuries in WNBA athletes has been on the rise, despite the high rates of ACL injury there is a paucity of recent research examining the effect of ACL reconstruction on RTP and performance in these athletes. This cohort study seeks to quantify the effect of ACL reconstruction on RTP and performance on WNBA athletes. Methods: All ACL tears sustained in the WNBA from 1997-2018 were identified. BMI, age and position at the time of injury were collected for each player. RTP rates were calculated and performance data was collected for each player before and after injury to determine changes in playing time and statistical performance. Players who successfully RTP after ACL reconstruction were compared to a group of healthy controls who were matched by age, years of experience, position, height, and BMI. Statistics at one year and three years’ post-injury were compared to assess acute and longitudinal changes in performance relative to pre-injury baseline. Results: A total of fifty-nine WNBA players sustained an isolated ACL tear during the study period. Forty-one (69.5%) were able to RTP. There was no difference in demographic characteristics between forty-one players and matched controls. Following RTP athletes played an average of 7.5±12.8 fewer games, 5.1±9.2 fewer minutes per game, and scored 3.7±5.0 less points per game in their first year compared to the year prior to injury. (Table1) When compared to matched controls, WNBA players returning from ACL reconstruction demonstrated a significant decline in games played, games started, minutes per game, rebounds, assists, and blocks per game in their first season after RTP. These differences resolved by year three post-surgery (Table 2). Conclusions: There is a high RTP rate following ACL reconstruction in WNBA athletes. Players may experience a decrease in playing time and performance initially when returning to play, however these variables were found to return to baseline over time.


Author(s):  
Chen-Hsiu Sung ◽  
Pen-hsiu Grace Chao

Type I collagen, the most abundant extracellular matrix component in the body, exists as fibers that are organized in wavy parallel fibers in many tissues [1, 2]. Cells embedded within this wavy pattern exhibit a 3D morphology that undulates with the fibers. The phenomenon that cell morphology follows substrate structure, such as cell elongation when attached to fibrous materials, is known as contact guidance [3]. As the cytoskeleton supports cellular structures and mediate numerous intracellular processes, changes to the cytoskeleton structures lead to modified cell behaviors and even fate [4, 5]. Studies have shown that fibroblasts express more ligament phenotypic markers when cultured on straight micropatterns or aligned fibers [6, 7]. However, few studies have investigated the influences of the wavy structures. To characterize the effects of the wavy structure, anterior cruciate ligament (ACL) fibroblasts were seeded in wavy microgrooves and their morphological responses were analyzed.


2021 ◽  
Vol 22 (15) ◽  
pp. 8204
Author(s):  
Clemens Gögele ◽  
Jens Konrad ◽  
Judith Hahn ◽  
Annette Breier ◽  
Michaela Schröpfer ◽  
...  

Anterior cruciate ligament (ACL) ruptures are usually treated with autograft implantation to prevent knee instability. Tissue engineered ACL reconstruction is becoming promising to circumvent autograft limitations. The aim was to evaluate the influence of cyclic stretch on lapine (L) ACL fibroblasts on embroidered scaffolds with respect to adhesion, DNA and sulphated glycosaminoglycan (sGAG) contents, gene expression of ligament-associated extracellular matrix genes, such as type I collagen, decorin, tenascin C, tenomodulin, gap junctional connexin 43 and the transcription factor Mohawk. Control scaffolds and those functionalized by gas phase fluorination and cross-linked collagen foam were either pre-cultured with a suspension or with spheroids of LACL cells before being subjected to cyclic stretch (4%, 0.11 Hz, 3 days). Stretch increased significantly the scaffold area colonized with cells but impaired sGAGs and decorin gene expression (functionalized scaffolds seeded with cell suspension). Stretching increased tenascin C, connexin 43 and Mohawk but decreased decorin gene expression (control scaffolds seeded with cell suspension). Pre-cultivation of functionalized scaffolds with spheroids might be the more suitable method for maintaining ligamentogenesis in 3D scaffolds compared to using a cell suspension due to a significantly higher sGAG content in response to stretching and type I collagen gene expression in functionalized scaffolds.


2020 ◽  
Vol 11 (1) ◽  
pp. 130
Author(s):  
Datao Xu ◽  
Xinyan Jiang ◽  
Xuanzhen Cen ◽  
Julien S. Baker ◽  
Yaodong Gu

Volleyball players often land on a single leg following a spike shot due to a shift in the center of gravity and loss of balance. Landing on a single leg following a spike may increase the probability of non-contact anterior cruciate ligament (ACL) injuries. The purpose of this study was to compare and analyze the kinematics and kinetics differences during the landing phase of volleyball players using a single leg (SL) and double-leg landing (DL) following a spike shot. The data for vertical ground reaction forces (VGRF) and sagittal plane were collected. SPM analysis revealed that SL depicted a smaller knee flexion angle (about 13.8°) and hip flexion angle (about 10.8°) during the whole landing phase, a greater knee and hip power during the 16.83–20.45% (p = 0.006) and 13.01–16.26% (p = 0.008) landing phase, a greater ankle plantarflexion angle and moment during the 0–41.07% (p < 0.001) and 2.76–79.45% (p < 0.001) landing phase, a greater VGRF during the 5.87–8.25% (p = 0.029), 19.75–24.14% (p = 0.003) landing phase when compared to DL. Most of these differences fall within the time range of ACL injury (30–50 milliseconds after landing). To reduce non-contact ACL injuries, a landing strategy of consciously increasing the hip and knee flexion, and plantarflexion of the ankle should be considered by volleyball players.


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