Introduction
The knee joint is present between the bones of the upper and the lower leg. The knee joint is a junction of three bones: femur or thigh bone, patella or kneecap, and tibia or shinbone. The function of the knee joint depends upon different cartilages, ligaments, and tendons. Dislocation of the knee joint occurs due to the disrupted position of the thigh bone or femur and shinbone or tibia. Knee joint dislocation is usually seen in sports. Accidents, trauma, falling, sudden twisting, or sports injuries can all cause knee dislocation. Dislocated knee and dislocated kneecap are both different conditions. The kneecap dislocation occurs due to the displacement of the kneecap from its right place. Direct blows to the kneecap or accidents can result in kneecap dislocations. Knee dislocation is not very common, but it is a serious condition, as it can cause severe damage to the attached ligaments, blood vessels, cartilage, tendons, and nerves. It causes difficulty in normal routine activities, sports, and work.
What Are the Symptoms of a Dislocated Knee?
The following symptoms occur just after a dislocated knee and worsen as time passes. In some cases, the knee gets back to its position by itself, but it is a rare condition. Symptoms of knee joint dislocation are listed below -
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Popping sound from the knee joint.
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Severe pain in the knee joint.
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The deformity can be seen in the knee joint.
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Knee joint instability or feeling of joint giving away.
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Limited range of motion of the joints.
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Swelling in the area of dislocation.
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Inability to move, walk and perform sports and daily routine.
How Is a Dislocated Knee Diagnosed?
A healthcare provider will stabilize the dislocated joint. The priority in case of dislocation is the reduction or repositioning of the dislocated knee joint. The reduction is important to release any pressure from the nerves and vessels in the area of injury. In some cases, the reduction of dislocated joints is possible without any medical professionals.
After stabilizing the joint, the doctor will go for the diagnosis of the injury. They will ask for different tests to determine the extent of the injury and involved structures like ligaments, tendons, nerves, and vessels. These tests help determine the knee's stability and range of motion. A dislocated knee can cause serious damage to the blood vessels and nerves of the knee joint, and the doctor will ask for tests to diagnose these damages.
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Checking the Pulse - The doctor will check for pulses in different places in the leg. This is known as a posterior tibial and dorsal pedal (present in the legs around the knee area) pulse checking. A low pulse indicates an injury to a blood vessel.
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Checking the Blood Pressure - The doctor will check the blood pressure in the injured leg. This procedure is known as the ankle-brachial index (ABI). Then the doctor will compare the ankle's blood pressure with the arm's blood pressure. Low ABI measurements indicate poor blood flow to the lower limb.
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Checking Sensation - The doctor will compare the feeling of the injured leg with the unaffected leg to check the sensation of touch and reflexes.
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Nerve Conduction - The doctor will ask for tests to check the nerve function. Electromyography (EMG) and nerve conduction velocity (NCV) help check nerve conduction. The doctor will also check for any color or temperature changes in the skin. Cold legs or color changes in the injured leg occur due to injury of blood vessels.
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Digital Imaging - X-rays and MRIs can help the doctor to see and diagnose any damage to the knee bones, ligaments, or tendons.
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Arteriogram - This technique is used to check blood vessel damage. In this procedure, a dye is injected into the leg vessels, and the doctor checks the vessels with the help of X-rays.
What Is Congenital Knee Dislocation (CKD)?
When the knee joint gets dislocated at birth, it is known as CKD. It is an unusual condition. It can be caused for many reasons. It can occur with other developmental problems also.
CKD is diagnosed after birth. X-ray imaging of the joint helps in diagnosis. Serial casting or surgery are treatment options.
What Is the Treatment for a Dislocated Knee?
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Treatment of knee dislocation should be started by checking the knee cap (whether it is in its right position or not). If the kneecap is not in the right position, place it back with the reduction process. The reduction process is done under medication or anesthesia so the injured person does not feel pain or discomfort. The healthcare provider will move the leg in particular ways, and the kneecap gets settled in the right position.
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After the reduction process, a brace is used to keep the injured leg in a stable position and prevent the kneecap movement to avoid further damage.
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Severe injury may require surgery to fix damaged ligaments, blood vessels, and nerves. Severely damaged blood vessels require immediate surgery.
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Conservative treatment is also used in some cases. It includes immobilization of the injured joint, rest, and medication. Conservative treatment is used in cases such as stable joints after kneecap reduction, blood vessels and nerves are not damaged, and when the ligaments are attached. Conservative treatments can stabilize the knee joint, but they can cause stiff joints in the future.
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After the treatment of knee dislocation (whether it is done by conservative treatment or surgical process), rehabilitation is important. Physical therapy helps in increasing the range of motion and faster recovery. The rehabilitation plan depends upon the severity of the injury and the treatment done. The doctor will suggest a rehabilitation program.
What Factors Are Responsible for Dislocated Knee Depend?
A knee dislocation depends on many factors, some of which are listed below -
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Cause of the injury.
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The extent of the injury.
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Injury to the blood vessels or nerves.
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The type of treatment used.
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Rehabilitation follow-ups.
Conclusion
Knee joint dislocation is a painful condition and can cause serious damage to the surrounding tissues and attachments, such as nerves, vessels, ligaments, and tendons. It is important to diagnose knee joint dislocation early and properly. Better diagnosis results in better treatment. This condition can be treated by conservative or surgical treatment followed by a rehabilitation program. If it is not treated properly, it can result in compartment syndrome and deep vein thrombosis.
