FAQS on Anterior Cruciate Ligament (ACL) injury
A few years ago, anterior cruciate ligament (ACL) injury means end of career for many NFL and NBA players. The problem is also equally threatening in gymnasts, wrestlers, skiing pros, and common people. About 200,000 people are diagnosed with ACL injuries every year. Women are at increased risk of ACL injuries than men. With the latest surgical and nonsurgical treatment options, the knee’s full functional ability can be regained.
What is ACL injury?
ACL injury refers to sprain or tearing in the anterior cruciate ligament. It may happen with or without contact. Simultaneous occurring of hyperextension and pivot exceeding biomechanical limits of the ligament hurts it.
Based on the severity, ACL injuries can be categorized into:
- Grade 1 sprains or mild damage without any major adverse effect
- Grade 2 sprains or loosening of the ligament causing partial tears
- Grade 3 sprains or serious damage leading to torn ligament or its separation into two parts
Grade 3 injuries or completely torn anterior cruciate ligament is the most common type of ACL injuries occurring in patients. It makes the knee joint unstable, weak, and functionally deficient. While rotatory instability is the immediate side effect, the problem, in the long term, leads to degenerative knee arthritis.
How does ACL injury occur?
ACL injuries primarily occur due to excessive mechanical load on the ligament and failure of the ligament to bear the stress.
The knee has four types of rope-like ligaments responsible for connecting bones with each other. Medial and lateral collateral ligaments positioned on the sides of the knee regulate the sideways motion while preventing atypical movements. Interior and posterior cruciate ligaments located in the front and back of the knee regulates the back and forth motion while protecting against any abnormal movement. The anterior cruciate ligament placed within the knee joint, it keeps “the tibia from sliding out in front of the femur,” prevents excessive twisting or straightening, and provides rotational stability.
When the anterior cruciate ligament is subject to hyperextension, associated the movement of the tibia, beyond its ability to withstand, sprain or tears appear causing ACL injuries.
What are the symptoms of ACL injury? When to see a doctor?
- A popping noise accompanies ACL injuries
- Knee giving out feeling
- Pain with swelling
- Tenderness in the knee joint
- Unstable knee
- Loss of knee movement
- Discomfort, pain while walking or weight lifting
What causes ACL injury?
- Hyperextension of the knee
- Excessive forward movement of the tibia
- Knee hit hard (example tackle during playing football)
- Sudden stoppage, turning, or change of direction while walking or running
- Twisting of the knee
- Forceful, incorrect landing on the feet
- Collision with others causing injury to the knee
- Week knee muscles
- Week knee alignment
- Missing a step while descending on the staircase
What are the risk factors?
Women and those with weak knee structure are at the risk of ACL injuries. It may also increase if you suffer from obesity, hamstring injury, or play high risk sports. About 70% of anterior cruciate ligament injuries are traced to non-contact factor, such as out of control landings, sudden deceleration, pivoting, and sidestepping maneuvers.
How is ACL injury diagnosed?
- Physical Exmination
- Pivot-shift test or ACL injury verification through knee instability.
- Anterior drawer test or ACL injury examination based on tibia displacement comparison
- Lachman test or analysis through tibia forward movement
- A thorough analysis of anterior cruciate ligament injury symptoms
- Imaging Tests
- X-rays to eliminate possible bone fractures
- MRI tests to identify the extent of the injury and impact on the knee
- Ultrasound to examine injury to ligaments and muscles around the knee joint
What are the treatment methods available for ACL injury?
- Conservative Therapy
- Rest and self-care
- Using knee brace or crutches to avoid stress on the knee
- Physical therapy and rehab
- Gradual exercises to regain knee motion, strengthen muscles, and increase knee stability
- Surgical Treatment
Surgical rebuilding of the ligament is an alternative if the injury is serious and non-surgical treatments fails to provide the desired result. It procedure involves ACL reconstruction, as stitching and restructuring are not options. The torn anterior cruciate ligament is replaced by grafting tissues obtained from patellar, hamstring, or quadriceps tendons. Cadaver ligaments are also grafted. These, tissues grow into new anterior cruciate ligament.
- Anesthetic injections for long-duration pain management and swelling control
- Prolotherapy injections that inject stem cells or platelet rich plasma to activate the regeneration and repair of the anterior cruciate ligament naturally.
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