Background and Etiology
Ligaments are fibrous bands of connective tissue made of collagen, which join bone to bone. Ligaments provide stability and limit excessive motion of the joint. The knee has four major ligaments: the medial collateral (MCL), lateral collateral (LCL), anterior cruciate (ACL) and posterior cruciate ligaments (PCL). Each ligament performs a vital role in the stability of the knee, which is the largest joint in the body. If a ligament is injured or torn, both the function and stability of the knee can be compromised.
There are three grades of ligament damage
Grade I is considered a sprain of the ligament because there is no actual tear. Individuals with a grade I injury experience minimal symptoms, but may report pain over the ligament and tenderness to palpation, or touch. The knee may feel stiff and there is discomfort during activities that stress the ligament. With testing, there is no laxity of the joint.
Grade II injuries are partial or incomplete tears of the ligament. Individuals may experience pain, tenderness, possible swelling and have difficulty bending or straightening the knee. There may be a feeling of “giving out” and instability during twisting motions. With testing, there is some laxity or looseness of the joint.
Grade III ligament injuries are complete tears. Individuals may experience pain, swelling and loss of motion of the knee. There is a feeling of instability and “giving out” when putting weight on the knee. There is significant laxity with testing of the joint. Often other structures are involved in the injury like the anterior and posterior cruciate ligaments (ACL, PCL). Surgery may be indicated due to associated rotatory instability in the case of lateral collateral ligament injuries.
Lateral Collateral Ligament
The lateral collateral ligament (LCL), also known as the fibula collateral ligament, is located on the outside of the knee. The LCL connects the lateral aspect of the femur to the head of the fibula, which is the smaller of the two bones of the lower leg. The function of the LCL is to prevent lateral opening or gapping of the knee joint. The LCL is not connected to the lateral meniscus, which is different from the medial collateral ligament (MCL), and is connected to the medial meniscus.
The most common cause of this injury is direct impact or blow to the medial (inside) of the knee causing a sudden gapping force on the outside of the knee.
- The lateral collateral ligament (LCL) can become strained, stretched or torn
- The greater the force, the more severe the ligament injury
- The lateral collateral ligament (LCL) is not attached to the lateral meniscus so damage to it is not associated with a meniscal tear
- Significant LCL damage can be associated with injury to the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL)
In response to this type of injury one should initiate the RICE protocol of Rest, Ice, Compression, and Elevation in addition to the following:
- Rest to avoid aggravating the injured knee and ligament through excessive activity.
- Immobilization to keep the ligament from being stressed any further and promote healing in the correct position. Depending on the severity of the injury the knee may be immobilized for a period of time.
- Ice to reduce inflammation and pain for the first 48-72 hours. Do not apply directly over skin and use ice intermittently during the day. Apply the ice for 20 minutes at a time. Do not apply any form of heat during this period.
- Contact your physician medical provider for complete diagnostic evaluation of the injury and follow up care.
- Physical Therapy may be indicated to treat and rehabilitate this injury for Grade I-III injuries.
- Grade III injuries may require repair of the lateral collateral ligament.
Physical Therapy Interventions
Physical Therapists are professionals, educated and trained to administer interventions. As stated in The Guide to Physical Therapist Practice interventions are the skilled and purposeful use of physical therapy methods and techniques to produce changes consistent with the diagnosis, prognosis, and the goals of the patient or client.
Initial treatment will be focused on protecting the ligament, reducing pain and swelling, as well as restoring motion. As the physical therapy program progresses, strengthening, flexibility, and aerobic exercises, in addition to technique and proprioceptive training to protect the knee and ligament will be added in an effort to restore normal activity level.
Grade I-II injuries may start off with immobilization to protect the ligament and joint. Physical therapy will be progressed based on the individual’s symptoms, with the removal of the immobilizing device and initiation of a stretching, strength and functional rehabilitation program.
Grade III injuries may require surgery, especially if other structures (like the ACL or PCL) are involved. Repair or tightening of the ligament may be necessary. Physical therapy will focus on restoring motion, strength and function based on the physician’s post-operative protocol. Full return to activity will depend on:
- Restoration of pain free full range of motion
- Patient ambulating independently without a limp
- Objective quadriceps strength in the 90% range
Physical Therapy Interventions
Common physical therapy interventions for this condition include:
- Manual Therapeutic Technique (MTT): hands on care including soft tissue massage, deep friction massage and joint mobilization by a physical therapist to regain mobility and range of motion of the knee.
- Therapeutic Exercises (TE) including stretching and strengthening exercises to regain range of motion and strength to protect and stabilize the knee and affected ligament.
- Neuromuscular Reeducation (NMR) to restore stability, begin retraining the lower extremity chain and improve movement technique and mechanics (running, jumping and cutting) in use of the involved knee in daily activities.
- Modalities that can include use of ultrasound, electrical stimulation, ultrasound, ice, cold laser and others to decrease pain and inflammation at the knee and ligament.
- Home program includes strengthening, stretching and stabilization exercises as well as instructions to help the person perform daily tasks and advance to the next functional level.
Following an injury to the lateral collateral ligament one should seek a full evaluation from a physician or health care provider. Treatment may consist of the following:
- Clinical evaluation including a physical exam, X-rays and MRI in more severe Grade III and Grade IV injury
- Use of ice and immobilization to stabilize and rest the joint
- Anti-inflammatory medication and pain medication as needed
- Progression to a hinged brace if indicated
- Referral to physical therapy to progress rehabilitation following a period of immobilization.
- Surgery may be indicated in Grade III-Grade IV injuries or cases involving damage to other knee structures (like the ACL or PCL) secondary to rotatory instability.
The prognosis for these injuries when cared for correctly is good. Time frames vary with the severity of the injury. As a general rule, Lateral Collateral Ligament (LCL) injuries take longer to return to full activity than Medial Collateral Ligament (MCL) injuries due to the ligament density and incidence of lateral instability with an LCL injury. Grade I and II may take 4-8 weeks while Grade III injuries will require 3-4 months.