ACL/PCL Sprain

Treatment in Salt Lake City, UT Advanced Muscle Integration Technique (A.M.I.T.)

ACL/PCL Sprain

Treatment in Salt Lake City, UT Advanced Muscle Integration Technique (A.M.I.T.)

ACL/PCL Sprain

Treatment in Salt Lake City, UT Advanced Muscle Integration Technique (A.M.I.T.)

How to Identify ACL/PCL Sprains and the AMIT Solution

The ACL and PCL are the two ligaments that cross inside the knee and keep the shinbone from sliding too far forward or backward under the thighbone. An ACL injury usually happens when pivoting, cutting, or landing from a jump, often with a popping sound and the knee giving out, followed by swelling within 24 hours. A PCL injury is less common and usually comes from a blow to the front of a bent knee.

ACL tears are among the most common knee injuries, affecting more than 200,000 people a year in the U.S., according to the American Academy of Orthopaedic Surgeons. Whether surgery is needed depends on the grade of the injury, your age, your activity level, and whether the knee feels unstable, but in every case the muscles around the knee decide how well it is protected afterward.

The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) are critical ligaments that bridge the inside of the knee joint, forming an "X" pattern that stabilizes the knee during front-to-back and back-to-front movement.

Injuries to these ligaments can cause significant instability and pain, leading to difficulty in everyday activities or athletic performance. This is one of the non-surgical hip and knee treatment AMIT addresses by restoring proper muscle activation instead of relying on surgery.

On This Page:

  • Causes of ACL/PCL Sprains

  • Symptoms of ACL/PCL Sprains

  • ACL vs. PCL Injuries

  • Sprain Grades and When Surgery Comes Up

  • AMIT Treatment for ACL/PCL Sprains

Causes of ACL/PCL Sprains

ACL and PCL injuries are often the result of:

  • Sudden Movements: A sudden stop, twist, pivot, or change in direction at the knee joint, particularly in sports, can lead to an ACL sprain or rupture.

  • Hyperextension: Overextending the knee, especially during athletic activities, can cause ligament damage.

  • Direct Impact: PCL sprains often result from a direct blow to the knee, such as landing hard on a bent knee during contact sports.

The most common cause of an ACL rupture is trauma from twisting motions or landing from a jump, while PCL sprains are often caused by direct impact to the front of the knee.

Most ACL injuries happen without any direct impact to the knee, during a sudden stop, a change of direction, or a bad landing. Female athletes have ACL injuries at rates 2 to 8 times higher than male athletes. A common PCL injury is a bent knee hitting the dashboard in a car accident or a football player falling on a bent knee.

Symptoms of ACL/PCL Sprains

Common signs of ACL and PCL injuries include:

  • Severe Knee Pain: Sharp pain at the time of injury, followed by difficulty in movement.

  • Swelling: Swelling in the knee joint, usually appearing within a few hours.

  • Instability: A feeling of the knee "giving out" during movement.

  • Limited Range of Motion: Difficulty fully extending or flexing the knee.

With an ACL injury you may hear a pop and feel the knee give out, and the knee typically swells within 24 hours. With a PCL injury, pain and swelling come on steadily after the injury, the knee may feel stiff, and walking can be difficult.

ACL vs. PCL Injuries

The two ligaments form an X inside the knee, but they are injured in different ways:

  • ACL (anterior cruciate ligament): Injured by pivoting, cutting, sudden stops, and landing from a jump, usually without contact. Common in soccer, basketball, football, and volleyball. Often happens along with damage to the MCL or a meniscus tear.

  • PCL (posterior cruciate ligament): Injured by a direct blow to the front of a bent knee, such as hitting the dashboard or falling on a bent knee. Less common than ACL injuries, and many PCL tears are partial tears with the potential to heal on their own.

Comparison of ACL and PCL injuries: how each happens, typical symptoms, and how often they occur

Sprain Grades and When Surgery Comes Up

Ligament injuries are graded by severity:

  1. Grade 1: The ligament is mildly damaged and slightly stretched, but it still helps keep the knee stable.

  2. Grade 2: The ligament is stretched to the point where it becomes loose. This is often called a partial tear.

  3. Grade 3: Most commonly called a complete tear. The ligament is split into two pieces and the knee is unstable.

An MRI shows how much ligament damage there is. Whether surgery is recommended for an ACL injury depends on the severity, your age, how much wear the joint already has, whether the knee feels unstable, and your activity level. For the PCL, surgery is most often recommended when several structures in the knee are injured together.

AMIT Treatment for ACL/PCL Sprains

What Happens During ACL/PCL Sprains?

During an ACL or PCL sprain, the quadriceps muscles become overloaded and inhibited. Other muscles, such as the gastrocnemius and popliteus, may also become inhibited, which complicates recovery and rehabilitation. This muscle inhibition leads to difficulty in engaging the quadriceps properly during recovery, making the knee more susceptible to further injury.

How Does AMIT Help?

Advanced Muscle Integration Technique (AMIT) focuses on reactivating these inhibited muscles to restore stability and proper function to the knee joint. By addressing muscle imbalances, AMIT can prevent further damage to the ligaments. Relief from knee pain and improved recovery can be achieved through treatment from a certified AMIT physician, who specializes in correcting these muscle inhibitions.

On a first visit we review any imaging, check knee stability, and test the quadriceps, gastrocnemius, popliteus, and hip muscles one at a time to find the ones that shut down. If the knee is unstable or an MRI has not been done after a significant injury, we refer you for an orthopedic evaluation first. The visit takes about 40 minutes; what to expect explains how to prepare, and post-surgical rehabilitation explains how we help after a reconstruction.

Diagram of the ACL and PCL sprain cycle: knee injury, overloaded and inhibited quadriceps, gastrocnemius, and popliteus, unstable knee, and higher risk of reinjury, with AMIT reactivating the inhibited muscles

Steps to Take If You Have ACL/PCL Sprains

  1. Consult a Certified AMIT Physician: A certified AMIT specialist can treat your knee injury using muscle activation techniques. Contact us today to schedule a consultation.

  2. Rehabilitation: Following AMIT treatment, our team will guide you through exercises to strengthen the quadriceps, gastrocnemius, and popliteus muscles, helping to restore function and prevent future injuries.

Why Choose AMIT for ACL/PCL Sprains?

  • Non-Invasive Treatment: AMIT provides a natural, non-surgical solution to ACL and PCL injuries.

  • Restore Knee Stability: By reactivating inhibited muscles, AMIT helps stabilize the knee and promote long-term recovery.

  • Prevents Re-Injury: AMIT corrects muscle imbalances that may lead to further cruciate ligament injuries.

If you're experiencing knee instability from an ACL or PCL sprain, contact Advanced Muscle Integration Clinics in the Salt lake City Area for professional, effective treatment using Advanced Muscle Integration Technique. A certified AMIT physician can help you regain stability and return to your activities. Call us today at 801.544.2355 or fill out our online form to schedule a consultation.

ACL and PCL Treatment in Draper and Kaysville

AMIT Clinics treats knee ligament injuries at both Utah locations: Draper, at 12371 S 900 E Unit 101, and Kaysville, at 447 North 300 West Ste 5. We see soccer, basketball, football, and ski injuries, and people working back after a reconstruction. Our article on knee injury treatment without surgery covers how we approach these injuries, and youth sports injury prevention is a good read for parents of athletes.

Frequently Asked Questions About ACL and PCL Sprains

How do I know if I tore my ACL?

Common signs are a popping noise at the time of injury, the knee giving out, pain, and swelling within 24 hours. An exam and an MRI confirm how much the ligament is damaged.

What is the difference between an ACL and a PCL injury?

ACL injuries usually happen from pivoting, cutting, or landing without contact. PCL injuries usually come from a blow to the front of a bent knee, such as hitting a dashboard, and are less common.

Does a torn ACL always need surgery?

Not always. The decision depends on the severity of the injury, your age, how much wear the joint has, whether the knee feels unstable, and your activity level.

Can a PCL tear heal on its own?

Many PCL tears are partial tears that have the potential to heal on their own. Surgery is usually considered when several structures in the knee are injured together.

Who is most at risk for an ACL tear?

Female athletes have ACL injuries at rates 2 to 8 times higher than male athletes. The American Academy of Orthopaedic Surgeons lists being female as a risk factor, along with looser joints, being younger, a higher body mass index, and decreased lower leg strength.

What are ACL sprain grades?

Grade 1 is a mild stretch with the knee still stable, Grade 2 stretches the ligament until it becomes loose, and Grade 3 is a complete tear.

Call 801.544.2355 to be seen.

Schedule an Appointment

Call: 801.544.2355

Or, use the link below to get started:

How to Identify ACL/PCL Sprains and the AMIT Solution

The ACL and PCL are the two ligaments that cross inside the knee and keep the shinbone from sliding too far forward or backward under the thighbone. An ACL injury usually happens when pivoting, cutting, or landing from a jump, often with a popping sound and the knee giving out, followed by swelling within 24 hours. A PCL injury is less common and usually comes from a blow to the front of a bent knee.

ACL tears are among the most common knee injuries, affecting more than 200,000 people a year in the U.S., according to the American Academy of Orthopaedic Surgeons. Whether surgery is needed depends on the grade of the injury, your age, your activity level, and whether the knee feels unstable, but in every case the muscles around the knee decide how well it is protected afterward.

The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) are critical ligaments that bridge the inside of the knee joint, forming an "X" pattern that stabilizes the knee during front-to-back and back-to-front movement.

Injuries to these ligaments can cause significant instability and pain, leading to difficulty in everyday activities or athletic performance. This is one of the non-surgical hip and knee treatment AMIT addresses by restoring proper muscle activation instead of relying on surgery.

On This Page:

  • Causes of ACL/PCL Sprains

  • Symptoms of ACL/PCL Sprains

  • ACL vs. PCL Injuries

  • Sprain Grades and When Surgery Comes Up

  • AMIT Treatment for ACL/PCL Sprains

Causes of ACL/PCL Sprains

ACL and PCL injuries are often the result of:

  • Sudden Movements: A sudden stop, twist, pivot, or change in direction at the knee joint, particularly in sports, can lead to an ACL sprain or rupture.

  • Hyperextension: Overextending the knee, especially during athletic activities, can cause ligament damage.

  • Direct Impact: PCL sprains often result from a direct blow to the knee, such as landing hard on a bent knee during contact sports.

The most common cause of an ACL rupture is trauma from twisting motions or landing from a jump, while PCL sprains are often caused by direct impact to the front of the knee.

Most ACL injuries happen without any direct impact to the knee, during a sudden stop, a change of direction, or a bad landing. Female athletes have ACL injuries at rates 2 to 8 times higher than male athletes. A common PCL injury is a bent knee hitting the dashboard in a car accident or a football player falling on a bent knee.

Symptoms of ACL/PCL Sprains

Common signs of ACL and PCL injuries include:

  • Severe Knee Pain: Sharp pain at the time of injury, followed by difficulty in movement.

  • Swelling: Swelling in the knee joint, usually appearing within a few hours.

  • Instability: A feeling of the knee "giving out" during movement.

  • Limited Range of Motion: Difficulty fully extending or flexing the knee.

With an ACL injury you may hear a pop and feel the knee give out, and the knee typically swells within 24 hours. With a PCL injury, pain and swelling come on steadily after the injury, the knee may feel stiff, and walking can be difficult.

ACL vs. PCL Injuries

The two ligaments form an X inside the knee, but they are injured in different ways:

  • ACL (anterior cruciate ligament): Injured by pivoting, cutting, sudden stops, and landing from a jump, usually without contact. Common in soccer, basketball, football, and volleyball. Often happens along with damage to the MCL or a meniscus tear.

  • PCL (posterior cruciate ligament): Injured by a direct blow to the front of a bent knee, such as hitting the dashboard or falling on a bent knee. Less common than ACL injuries, and many PCL tears are partial tears with the potential to heal on their own.

Comparison of ACL and PCL injuries: how each happens, typical symptoms, and how often they occur

Sprain Grades and When Surgery Comes Up

Ligament injuries are graded by severity:

  1. Grade 1: The ligament is mildly damaged and slightly stretched, but it still helps keep the knee stable.

  2. Grade 2: The ligament is stretched to the point where it becomes loose. This is often called a partial tear.

  3. Grade 3: Most commonly called a complete tear. The ligament is split into two pieces and the knee is unstable.

An MRI shows how much ligament damage there is. Whether surgery is recommended for an ACL injury depends on the severity, your age, how much wear the joint already has, whether the knee feels unstable, and your activity level. For the PCL, surgery is most often recommended when several structures in the knee are injured together.

AMIT Treatment for ACL/PCL Sprains

What Happens During ACL/PCL Sprains?

During an ACL or PCL sprain, the quadriceps muscles become overloaded and inhibited. Other muscles, such as the gastrocnemius and popliteus, may also become inhibited, which complicates recovery and rehabilitation. This muscle inhibition leads to difficulty in engaging the quadriceps properly during recovery, making the knee more susceptible to further injury.

How Does AMIT Help?

Advanced Muscle Integration Technique (AMIT) focuses on reactivating these inhibited muscles to restore stability and proper function to the knee joint. By addressing muscle imbalances, AMIT can prevent further damage to the ligaments. Relief from knee pain and improved recovery can be achieved through treatment from a certified AMIT physician, who specializes in correcting these muscle inhibitions.

On a first visit we review any imaging, check knee stability, and test the quadriceps, gastrocnemius, popliteus, and hip muscles one at a time to find the ones that shut down. If the knee is unstable or an MRI has not been done after a significant injury, we refer you for an orthopedic evaluation first. The visit takes about 40 minutes; what to expect explains how to prepare, and post-surgical rehabilitation explains how we help after a reconstruction.

Diagram of the ACL and PCL sprain cycle: knee injury, overloaded and inhibited quadriceps, gastrocnemius, and popliteus, unstable knee, and higher risk of reinjury, with AMIT reactivating the inhibited muscles

Steps to Take If You Have ACL/PCL Sprains

  1. Consult a Certified AMIT Physician: A certified AMIT specialist can treat your knee injury using muscle activation techniques. Contact us today to schedule a consultation.

  2. Rehabilitation: Following AMIT treatment, our team will guide you through exercises to strengthen the quadriceps, gastrocnemius, and popliteus muscles, helping to restore function and prevent future injuries.

Why Choose AMIT for ACL/PCL Sprains?

  • Non-Invasive Treatment: AMIT provides a natural, non-surgical solution to ACL and PCL injuries.

  • Restore Knee Stability: By reactivating inhibited muscles, AMIT helps stabilize the knee and promote long-term recovery.

  • Prevents Re-Injury: AMIT corrects muscle imbalances that may lead to further cruciate ligament injuries.

If you're experiencing knee instability from an ACL or PCL sprain, contact Advanced Muscle Integration Clinics in the Salt lake City Area for professional, effective treatment using Advanced Muscle Integration Technique. A certified AMIT physician can help you regain stability and return to your activities. Call us today at 801.544.2355 or fill out our online form to schedule a consultation.

ACL and PCL Treatment in Draper and Kaysville

AMIT Clinics treats knee ligament injuries at both Utah locations: Draper, at 12371 S 900 E Unit 101, and Kaysville, at 447 North 300 West Ste 5. We see soccer, basketball, football, and ski injuries, and people working back after a reconstruction. Our article on knee injury treatment without surgery covers how we approach these injuries, and youth sports injury prevention is a good read for parents of athletes.

Frequently Asked Questions About ACL and PCL Sprains

How do I know if I tore my ACL?

Common signs are a popping noise at the time of injury, the knee giving out, pain, and swelling within 24 hours. An exam and an MRI confirm how much the ligament is damaged.

What is the difference between an ACL and a PCL injury?

ACL injuries usually happen from pivoting, cutting, or landing without contact. PCL injuries usually come from a blow to the front of a bent knee, such as hitting a dashboard, and are less common.

Does a torn ACL always need surgery?

Not always. The decision depends on the severity of the injury, your age, how much wear the joint has, whether the knee feels unstable, and your activity level.

Can a PCL tear heal on its own?

Many PCL tears are partial tears that have the potential to heal on their own. Surgery is usually considered when several structures in the knee are injured together.

Who is most at risk for an ACL tear?

Female athletes have ACL injuries at rates 2 to 8 times higher than male athletes. The American Academy of Orthopaedic Surgeons lists being female as a risk factor, along with looser joints, being younger, a higher body mass index, and decreased lower leg strength.

What are ACL sprain grades?

Grade 1 is a mild stretch with the knee still stable, Grade 2 stretches the ligament until it becomes loose, and Grade 3 is a complete tear.

Call 801.544.2355 to be seen.

Schedule an Appointment

Call: 801.544.2355

Or, use the link below to get started:

How to Identify ACL/PCL Sprains and the AMIT Solution

The ACL and PCL are the two ligaments that cross inside the knee and keep the shinbone from sliding too far forward or backward under the thighbone. An ACL injury usually happens when pivoting, cutting, or landing from a jump, often with a popping sound and the knee giving out, followed by swelling within 24 hours. A PCL injury is less common and usually comes from a blow to the front of a bent knee.

ACL tears are among the most common knee injuries, affecting more than 200,000 people a year in the U.S., according to the American Academy of Orthopaedic Surgeons. Whether surgery is needed depends on the grade of the injury, your age, your activity level, and whether the knee feels unstable, but in every case the muscles around the knee decide how well it is protected afterward.

The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) are critical ligaments that bridge the inside of the knee joint, forming an "X" pattern that stabilizes the knee during front-to-back and back-to-front movement.

Injuries to these ligaments can cause significant instability and pain, leading to difficulty in everyday activities or athletic performance. This is one of the non-surgical hip and knee treatment AMIT addresses by restoring proper muscle activation instead of relying on surgery.

On This Page:

  • Causes of ACL/PCL Sprains

  • Symptoms of ACL/PCL Sprains

  • ACL vs. PCL Injuries

  • Sprain Grades and When Surgery Comes Up

  • AMIT Treatment for ACL/PCL Sprains

Causes of ACL/PCL Sprains

ACL and PCL injuries are often the result of:

  • Sudden Movements: A sudden stop, twist, pivot, or change in direction at the knee joint, particularly in sports, can lead to an ACL sprain or rupture.

  • Hyperextension: Overextending the knee, especially during athletic activities, can cause ligament damage.

  • Direct Impact: PCL sprains often result from a direct blow to the knee, such as landing hard on a bent knee during contact sports.

The most common cause of an ACL rupture is trauma from twisting motions or landing from a jump, while PCL sprains are often caused by direct impact to the front of the knee.

Most ACL injuries happen without any direct impact to the knee, during a sudden stop, a change of direction, or a bad landing. Female athletes have ACL injuries at rates 2 to 8 times higher than male athletes. A common PCL injury is a bent knee hitting the dashboard in a car accident or a football player falling on a bent knee.

Symptoms of ACL/PCL Sprains

Common signs of ACL and PCL injuries include:

  • Severe Knee Pain: Sharp pain at the time of injury, followed by difficulty in movement.

  • Swelling: Swelling in the knee joint, usually appearing within a few hours.

  • Instability: A feeling of the knee "giving out" during movement.

  • Limited Range of Motion: Difficulty fully extending or flexing the knee.

With an ACL injury you may hear a pop and feel the knee give out, and the knee typically swells within 24 hours. With a PCL injury, pain and swelling come on steadily after the injury, the knee may feel stiff, and walking can be difficult.

ACL vs. PCL Injuries

The two ligaments form an X inside the knee, but they are injured in different ways:

  • ACL (anterior cruciate ligament): Injured by pivoting, cutting, sudden stops, and landing from a jump, usually without contact. Common in soccer, basketball, football, and volleyball. Often happens along with damage to the MCL or a meniscus tear.

  • PCL (posterior cruciate ligament): Injured by a direct blow to the front of a bent knee, such as hitting the dashboard or falling on a bent knee. Less common than ACL injuries, and many PCL tears are partial tears with the potential to heal on their own.

Comparison of ACL and PCL injuries: how each happens, typical symptoms, and how often they occur

Sprain Grades and When Surgery Comes Up

Ligament injuries are graded by severity:

  1. Grade 1: The ligament is mildly damaged and slightly stretched, but it still helps keep the knee stable.

  2. Grade 2: The ligament is stretched to the point where it becomes loose. This is often called a partial tear.

  3. Grade 3: Most commonly called a complete tear. The ligament is split into two pieces and the knee is unstable.

An MRI shows how much ligament damage there is. Whether surgery is recommended for an ACL injury depends on the severity, your age, how much wear the joint already has, whether the knee feels unstable, and your activity level. For the PCL, surgery is most often recommended when several structures in the knee are injured together.

AMIT Treatment for ACL/PCL Sprains

What Happens During ACL/PCL Sprains?

During an ACL or PCL sprain, the quadriceps muscles become overloaded and inhibited. Other muscles, such as the gastrocnemius and popliteus, may also become inhibited, which complicates recovery and rehabilitation. This muscle inhibition leads to difficulty in engaging the quadriceps properly during recovery, making the knee more susceptible to further injury.

How Does AMIT Help?

Advanced Muscle Integration Technique (AMIT) focuses on reactivating these inhibited muscles to restore stability and proper function to the knee joint. By addressing muscle imbalances, AMIT can prevent further damage to the ligaments. Relief from knee pain and improved recovery can be achieved through treatment from a certified AMIT physician, who specializes in correcting these muscle inhibitions.

On a first visit we review any imaging, check knee stability, and test the quadriceps, gastrocnemius, popliteus, and hip muscles one at a time to find the ones that shut down. If the knee is unstable or an MRI has not been done after a significant injury, we refer you for an orthopedic evaluation first. The visit takes about 40 minutes; what to expect explains how to prepare, and post-surgical rehabilitation explains how we help after a reconstruction.

Diagram of the ACL and PCL sprain cycle: knee injury, overloaded and inhibited quadriceps, gastrocnemius, and popliteus, unstable knee, and higher risk of reinjury, with AMIT reactivating the inhibited muscles

Steps to Take If You Have ACL/PCL Sprains

  1. Consult a Certified AMIT Physician: A certified AMIT specialist can treat your knee injury using muscle activation techniques. Contact us today to schedule a consultation.

  2. Rehabilitation: Following AMIT treatment, our team will guide you through exercises to strengthen the quadriceps, gastrocnemius, and popliteus muscles, helping to restore function and prevent future injuries.

Why Choose AMIT for ACL/PCL Sprains?

  • Non-Invasive Treatment: AMIT provides a natural, non-surgical solution to ACL and PCL injuries.

  • Restore Knee Stability: By reactivating inhibited muscles, AMIT helps stabilize the knee and promote long-term recovery.

  • Prevents Re-Injury: AMIT corrects muscle imbalances that may lead to further cruciate ligament injuries.

If you're experiencing knee instability from an ACL or PCL sprain, contact Advanced Muscle Integration Clinics in the Salt lake City Area for professional, effective treatment using Advanced Muscle Integration Technique. A certified AMIT physician can help you regain stability and return to your activities. Call us today at 801.544.2355 or fill out our online form to schedule a consultation.

ACL and PCL Treatment in Draper and Kaysville

AMIT Clinics treats knee ligament injuries at both Utah locations: Draper, at 12371 S 900 E Unit 101, and Kaysville, at 447 North 300 West Ste 5. We see soccer, basketball, football, and ski injuries, and people working back after a reconstruction. Our article on knee injury treatment without surgery covers how we approach these injuries, and youth sports injury prevention is a good read for parents of athletes.

Frequently Asked Questions About ACL and PCL Sprains

How do I know if I tore my ACL?

Common signs are a popping noise at the time of injury, the knee giving out, pain, and swelling within 24 hours. An exam and an MRI confirm how much the ligament is damaged.

What is the difference between an ACL and a PCL injury?

ACL injuries usually happen from pivoting, cutting, or landing without contact. PCL injuries usually come from a blow to the front of a bent knee, such as hitting a dashboard, and are less common.

Does a torn ACL always need surgery?

Not always. The decision depends on the severity of the injury, your age, how much wear the joint has, whether the knee feels unstable, and your activity level.

Can a PCL tear heal on its own?

Many PCL tears are partial tears that have the potential to heal on their own. Surgery is usually considered when several structures in the knee are injured together.

Who is most at risk for an ACL tear?

Female athletes have ACL injuries at rates 2 to 8 times higher than male athletes. The American Academy of Orthopaedic Surgeons lists being female as a risk factor, along with looser joints, being younger, a higher body mass index, and decreased lower leg strength.

What are ACL sprain grades?

Grade 1 is a mild stretch with the knee still stable, Grade 2 stretches the ligament until it becomes loose, and Grade 3 is a complete tear.

Call 801.544.2355 to be seen.

Schedule an Appointment

Call: 801.544.2355

Or, use the link below to get started: