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 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 on 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. The use of a knee brace or immobilizing device may be required to stabilize, rest and promote healing of the ligament and joint. There is significant laxity with testing of the joint.
Grade IV ligament injury is called a medial column injury because the injury affects more than just the medial collateral ligament (for example: the meniscus or ACL). These types of injuries may require surgery.
Medial Collateral Ligament
The medial collateral ligament (MCL), also known as the tibial collateral ligament, is located on the inside of the knee. The MCL connects the medial aspect of the femur to the medial aspect of the tibia. The function of the MCL is to prevent medial opening or gapping of the knee joint. The medial collateral ligament is connected to the medial meniscus therefore damage to the MCL can result in a tear of the medial meniscus.
The most common cause of this injury is a direct impact or blow to the lateral (outside) aspect of the knee causing a sudden gapping force on the inside of the knee. The medial collateral ligament can become strained, stretched or torn. A general rule of thumb is the greater the force, the more severe the ligament injury. The highest incidence of collateral ligament injuries is between 20-34 and 55-65 years of age, but they can occur at any age.
In response to this type of injury one should initiate 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 to 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 ice directly over the skin and only use ice intermittently during the day. Do not apply any form of heat during this period.
- Contact your physician or healthcare 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.
Initial treatment will focus on ligament protection, 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 and effort to restore a normal level of activity.
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 the initiation of a stretching, strengthening, and functional rehabilitation program.
Grade III injuries will require immobilization for a longer period of time and progression of weight bearing with use of a hinged brace to protect the ligament. Physical therapy will focus on restoring motion and strength. 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
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 medial 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 for more severe Grade III-IV injuries
- 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 if indicated in Grade IV or cases involving damage to other knee structures (like the meniscus or ACL.)
The prognosis for these injuries when cared for correctly is good. Time frames vary with the severity of the injury. Grade I injuries can take between 2-4 weeks to recover. Grade II injuries may take 4-6 weeks while Grade III injuries will require 3-4 months. A Grad IV injury with surgery will follow the physician protocol based on what other structures have been injured.