ACL Flashcards
What are some common concurrent injuries that often occur with ACL injuries?
Common concurrent injuries include meniscal tears (found in 57% of ACL injuries), and chondral (cartilage) injuries.
What are common symptoms that follow an ACL tear?
Common symptoms include
* swelling
* instability
* loss of range of motion
What are some important considerations when determining which prehab intervention to use?
Important considerations include:
- The individual’s demographic, as this can impact access, length of prehab, and adherence.
- The individual’s degree of desired activity level.
- The specific ACL reconstruction procedure that will be performed (graft choice, etc.).
What are the potential adverse reactions of periods of immobilization and limited mobilization after ACL surgery?
These periods can lead to adverse reactions such as anaerobic resistance and muscle atrophy.
What is the current gold standard for ACL reconstruction surgery?
The current gold standard is arthroscopic surgery using either a patellar tendon or hamstring graft, though this can vary.
Why is it clinically significant that BFR can produce similar hypertrophy as high-load training without excessively loading the knee?
This is important because excessive load on an injured knee can proliferate and prolong swelling, potentially leading to increased senescence of FAP cells that may contribute to muscle degeneration and fibrosis.
What are the potential drawbacks of prolonged Interleukin-6 (IL-6) levels?
Prolonged IL-6 levels can lead to excess oxidative stress and fibrosis, which may delay the healing process.
What are the limitations of the study on Omega-3s and IL-6?
The study was done on rats, not humans, and there wasn’t any follow-up. Other metabolites weren’t fully explained.
Why is electrical muscle stimulation (EMS) used in ACL prehab?
EMS is used to improve neuromuscular contractions and strength, particularly because ACL injuries can lead to arthrogenic muscle inhibition (AMI), which is the difficulty in fully and voluntarily contracting the muscle.
What are the limitations of current literature on EMS?
Current literature is considered low-grade evidence due to susceptibility to bias and placebo effects, and the mechanisms are non-universal to all injuries.
What is a significant risk associated with ACL injury that future research could address?
Individuals with an ACL injury are at a higher risk of developing osteoarthritis (40-80% of cases), and future research could study the efficacy of pre-operative interventions in reducing this risk.
What disparity exists in ACL research regarding female representation?
Women are 2-8 times more likely to have an ACL injury, but they make up a disproportionately small percentage of participants in ACL studies.
What are the main categories of prehab interventions that can be used before ACL surgery to improve recovery?
The main categories of prehab interventions are:
- Strength and balance training
- Blood flow restriction (BFR) therapy
- Omega-3 supplementation
- Electrical muscle stimulation (EMS)
How does pre-operative strength and balance training affect post-operative recovery after ACL reconstruction?
- particularly targeting the quadriceps and hamstrings, can help speed up recovery after ACL reconstruction.
- Greater strength before surgery leads to better recovery after surgery. It can also mitigate atrophy and stimulate ribosomal biogenesis, supporting muscle protein synthesis.
What are the benefits of blood flow restriction (BFR) therapy in ACL prehab?
BFR therapy, when used with low-load training, can produce similar increases in muscle cross-sectional area and strength as high-load training. It allows for similar hypertrophy as high-load training without excessively loading the knee.
What is a potential mechanism of action for BFR?
BFR may work by creating a hypoxic state in the muscle, and it up-regulates mRNA, ribosomal RNA transcription factors, and RNA binding proteins, which are important for ribosomal biogenesis and muscle protein synthesis.
What are the implications of using BFR as a pre-surgical intervention?
BFR can help produce similar hypertrophy as high-load training without excessively loading the knee, which is important in an injured state to prevent prolonged swelling and muscle degeneration.
What is the proposed benefit of Omega-3 supplementation in ACL prehab?
Omega-3 supplementation may help ligaments heal faster by influencing Interleukin-6 (IL-6) regulation.
How does Interleukin-6 (IL-6) relate to Omega-3 supplementation and ACL injury?
Pre-injury, IL-6 upregulation supports an effective immune response. Post-injury, IL-6 suppression may help limit excessive inflammation, potentially aiding recovery. Omega-3s may help in the short term by promoting inflammation, but suppressing IL-6 after the initial immune response may be beneficial for long-term healing.
What is arthrogenic muscle inhibition (AMI), and how does it relate to ACL injuries?
AMI is the difficulty in fully and voluntarily contracting a muscle, which can occur in the subacute phase after an ACL tear. It is caused by the injury disrupting neural input and output from the joint.
What is the proposed benefit of electrical muscle stimulation (EMS) in ACL prehab?
EMS aims to maximize the contractile ability of the joint to help strengthen it before surgery, addressing muscle atrophy that occurs from disuse and quadriceps inhibition.
What are the limitations and future directions for research in ACL prehab?
More research is needed on the efficacy of pre-operative interventions in reducing the risk of developing osteoarthritis. Increased female representation is needed in ACL studies to examine potential effects of hormones on injury and outcomes since females are 2-8x more likely to get an ACL tear. More research is needed to decide the efficacy of Electrical Muscle Stimulation intervention.
What is the key implication of blood flow restriction (BFR) therapy’s ability to produce similar muscle growth and strength gains as high-load training?
The key implication is that BFR therapy offers a way to achieve muscle strengthening and hypertrophy with less stress on the knee joint. This is particularly valuable in ACL prehab where excessive joint loading could exacerbate the injury or impede healing.
How does the impact of BFR on muscle protein synthesis and RNA synthesis influence its use in ACL prehab?
BFR’s positive influence on these factors suggests it can effectively stimulate the muscle’s growth and repair processes. This implies that BFR can be a valuable tool to counteract muscle atrophy before surgery, potentially leading to better post-operative outcomes.
