An ACL tear is one of the most important knee ligament injuries I evaluate in orthopedic practice. In Dhaka and across Bangladesh, I see this problem in football players, cricketers, badminton players, runners, gym-goers, students, and adults who twist the knee during a simple slip or fall. The injury may happen in seconds, but the effect on stability, work, and sport can last much longer if it is not assessed properly. [1][2]
The ACL, or anterior cruciate ligament, helps stop the shin bone from sliding too far forward and helps control rotational stability of the knee. When the ligament tears, the knee may no longer feel reliable during turning, stopping, pivoting, or landing. [2]
What happens in an ACL tear
An ACL tear is not just a pain problem. It is a stability problem.
The injury may be:
- a partial tear, where some fibers remain intact
- a complete tear, where the ligament no longer works normally
Partial tears can sometimes settle with good rehabilitation if the knee remains stable. Complete tears are more likely to create ongoing instability, especially in active patients who need to twist, cut, or change direction quickly. [1][2]
Common causes
I usually see ACL tears after movements such as:
- sudden change of direction
- stopping abruptly while running
- landing awkwardly from a jump
- twisting on a planted foot
- direct contact during sport
- road traffic or fall-related trauma
In Bangladesh, football and cricket are common settings for this injury, but I also see it after everyday slips, especially when a person turns quickly on a wet or uneven surface.
Symptoms patients often notice
The pattern can be very suggestive.
A pop or sudden shift
Some patients remember hearing or feeling a pop at the time of injury.
Swelling soon after injury
Swelling often appears within hours, which suggests bleeding inside the knee joint. [2]
Pain and difficulty moving the knee
The knee may feel painful, stiff, or difficult to fully bend or straighten.
Giving way or instability
This is one of the most important symptoms. Patients may say:
- “My knee gives way.”
- “It feels loose.”
- “I do not trust it when I walk or turn.”
That sense of instability matters more than the first-day pain. A knee that keeps giving way can injure the meniscus or cartilage over time. [1][2]
When to seek urgent evaluation
Not every ACL tear is an emergency, but some situations need prompt medical assessment.
Seek urgent care if there is:
- severe swelling soon after injury
- inability to bear weight
- a visible deformity
- numbness or weakness in the foot
- severe calf pain or swelling
- fever, redness, or warmth that raises concern for infection
- repeated locking that prevents straightening the knee
If the knee is unstable after a twisting injury, I would not advise ignoring it for weeks.
How I assess a suspected ACL tear
In my practice, I start with the story of the injury. I want to know:
- how the injury happened
- whether the knee twisted
- whether swelling came quickly
- whether there was a pop
- whether the knee now gives way
- whether there is locking, catching, or loss of motion
Then I examine the knee carefully. I check swelling, tenderness, motion, and stability. Clinical examination is very important, although pain and muscle guarding can make it harder in the first few days after injury. [2]
Tests that may be needed
X-ray
An X-ray does not show the ACL itself, but it helps rule out a fracture or other bony injury.
MRI
MRI is useful when I want to confirm the ACL injury and look for associated problems such as meniscus tear, cartilage injury, bone bruising, or damage to other ligaments. About half of ACL injuries occur with injury to other structures in the knee. [1][2]
Does every ACL tear need surgery?
No. That is one of the most common questions I hear.
The right treatment depends on:
- age
- activity level
- sports demands
- work demands
- degree of instability
- associated meniscus or cartilage injury
- the patient’s future goals
An active adult who plays pivoting sports or does heavy manual work is more likely to benefit from ACL reconstruction. A lower-demand patient with a stable knee after rehabilitation may do well without surgery in selected cases. [1][2]
Non-surgical treatment
Non-surgical treatment is not the same as doing nothing. It usually includes:
- swelling control
- pain control
- physiotherapy
- regaining knee motion
- strengthening the quadriceps and hamstrings
- balance and movement training
This approach is most suitable when the knee is stable enough for daily life and the patient can avoid high-risk twisting activities. [1]
When surgery becomes more important
I more strongly consider ACL reconstruction when:
- the knee repeatedly gives way
- the patient wants to return to pivoting or cutting sports
- the patient has a meniscus tear or other associated injury
- instability is affecting work or daily movement
- the knee remains unreliable despite rehabilitation
Repeated instability is the issue that can quietly damage the knee over time. [1][2]
What ACL reconstruction means
ACL reconstruction does not usually mean stitching the torn ligament back together. In most cases, the torn ACL is replaced with a graft, commonly taken from a tendon such as the hamstring, patellar tendon, or quadriceps tendon. [1]
