What causes a knee to pop out of place. How is patellar instability diagnosed. What are the symptoms of a dislocated kneecap. How can patellar dislocation be prevented. What treatment options are available for knee instability.

Understanding Patellar Instability: When Your Knee Feels Like It Popped Out

Patellar instability is a condition that can make you feel like your knee suddenly popped out of place and then back in again. This unsettling sensation occurs when the kneecap (patella) moves out of its normal position within the trochlear groove – a specially shaped part of the thighbone designed to cradle and guide the kneecap’s movement.

Patellar instability can be classified as either acute or chronic:

• Acute instability: Usually occurs during sports activities, particularly in football, basketball, and volleyball
• Chronic instability: Refers to recurring episodes of kneecap dislocation or subluxation

Young athletes between 13 and 20 years old are at the highest risk of experiencing patellar instability, with teenage females being particularly susceptible due to anatomical factors.

Subluxation vs. Dislocation: The Spectrum of Patellar Instability

When your knee “pops” out of place, it can be due to either subluxation or dislocation of the patella:

• Subluxation: A partial dislocation where the kneecap briefly shifts out of the groove before returning to its normal position
• Dislocation: The kneecap completely moves out of the groove and remains displaced

In a healthy knee, the patella glides smoothly up and down within the trochlear groove as you bend and straighten your leg. Patellar instability disrupts this normal tracking, leading to the sensation of your knee popping out of place.

What triggers a kneecap dislocation?

The most common causes of kneecap dislocation include:

1. Non-contact twisting injuries when the knee is almost fully extended
2. Direct blows to the kneecap during sports activities
3. Falls or other accidents that impact the knee

Recognizing the Signs: Symptoms of a Dislocated Knee

If you’ve experienced a knee dislocation, you may notice several distinct symptoms:

• Intense pain in the knee area
• Noticeable swelling around the joint
• Visible deformity of the knee
• Reduced range of motion
• Tenderness when touching the affected area
• Audible “popping” sounds during knee movement or while climbing stairs

These symptoms can vary in severity depending on whether you’ve experienced a partial subluxation or a complete dislocation.

Diagnosing Patellar Instability: From Medical History to Imaging

Accurate diagnosis of patellar instability involves several steps:

1. Review of medical history: Your doctor will inquire about your symptoms and any previous knee injuries
2. Physical examination: An apprehension test may be performed to assess the stability of your kneecap
3. Imaging studies: X-rays are often ordered to rule out fractures and evaluate the position of the kneecap

It’s crucial to seek medical attention even if your kneecap seems to have returned to its normal position on its own. A thorough evaluation can help identify any damage to surrounding structures such as muscles, ligaments, nerves, or blood vessels.

Why is prompt diagnosis important for knee dislocations?

Timely diagnosis of knee dislocations is essential because:

• It allows for early intervention and appropriate treatment
• It helps prevent further damage to the knee joint
• It can identify any associated injuries that may not be immediately apparent
• It guides the development of an effective rehabilitation plan

Treatment Options: From Conservative Approaches to Surgery

The treatment for patellar instability depends on the severity of the condition and the individual patient’s circumstances. Your orthopedic surgeon will determine the most appropriate course of action, which may include:

Non-surgical treatments:

• RICE protocol (Rest, Ice, Compression, Elevation) to reduce swelling
• Knee bracing to immobilize the joint
• Crutches to assist with weight-bearing and prevent knee buckling
• Physical therapy to strengthen muscles and improve range of motion

Surgical interventions:

For cases of chronic instability or complete kneecap dislocation, arthroscopic surgery may be recommended. This minimally invasive procedure allows the surgeon to repair damaged tissues and stabilize the kneecap.

Preventing Recurrence: Strategies to Keep Your Kneecap Stable

After experiencing patellar instability, it’s natural to want to prevent future episodes. Here are some effective strategies to reduce the risk of recurrence:

• Activity modification: Avoid movements that put excessive stress on your knees
• Regular stretching: Maintain flexibility in the muscles surrounding your knee
• Quadriceps strengthening: Build up the muscles that help stabilize your kneecap
• Knee bracing: Use supportive braces during high-risk activities
• Custom orthotics: Address any underlying foot or ankle issues that may contribute to knee instability
• Weight management: Maintain a healthy weight to reduce stress on your knee joints

How effective are these preventive measures?

While no strategy can guarantee complete prevention of patellar instability, implementing these measures can significantly reduce the risk of recurrence. Studies have shown that targeted exercise programs and proper biomechanics can decrease the likelihood of future dislocations by up to 50%.

When to Seek Medical Attention: Don’t Ignore Your Knee Pain

If you’ve experienced a knee injury or suspect patellar instability, it’s crucial to seek medical attention promptly. Contact a healthcare provider if you notice:

• Severe pain or swelling in your knee
• Visible deformity of the knee joint
• Inability to bear weight on the affected leg
• Recurring sensations of your knee “giving way” or popping out of place

Remember, even if your kneecap appears to have returned to its normal position, underlying damage may still be present. A thorough evaluation by a specialist can ensure proper diagnosis and treatment, potentially preventing long-term complications.

Living with Patellar Instability: Long-Term Management and Outlook

For individuals who have experienced patellar instability, long-term management is key to maintaining knee health and function. This may involve:

• Ongoing physical therapy to maintain muscle strength and joint stability
• Regular check-ups with an orthopedic specialist
• Lifestyle modifications to protect the knee during daily activities
• Use of supportive devices or braces during high-risk activities

What is the long-term prognosis for patellar instability?

The outlook for patellar instability varies depending on several factors:

• Severity of the initial injury
• Frequency of recurrence
• Adherence to treatment and prevention strategies
• Individual patient characteristics (age, activity level, etc.)

With proper management and care, many individuals with patellar instability can maintain an active lifestyle and avoid significant long-term complications. However, some may experience recurring issues or develop osteoarthritis in the affected knee over time.

Advancements in Treatment: Emerging Therapies for Patellar Instability

As medical research progresses, new treatments for patellar instability are being developed and refined. Some promising areas of advancement include:

• Regenerative medicine techniques, such as platelet-rich plasma (PRP) injections
• Improved surgical techniques for patellar stabilization
• Advanced bracing technologies for better knee support
• Personalized rehabilitation protocols based on individual patient factors

How might these advancements improve outcomes for patients?

These emerging therapies aim to:

• Enhance the body’s natural healing processes
• Provide more durable and less invasive surgical solutions
• Offer better protection against recurrent instability
• Tailor treatment approaches to each patient’s unique needs

While many of these treatments are still in various stages of research and development, they hold promise for improving the management of patellar instability in the future.

Understanding the Biomechanics: Why Patellar Instability Occurs

To fully grasp the concept of patellar instability, it’s helpful to understand the underlying biomechanics of the knee joint. The patella serves several important functions:

• Increasing the leverage of the quadriceps muscles
• Protecting the anterior aspect of the knee joint
• Centralizing the forces of the quadriceps tendon

Patellar instability can occur due to various factors that disrupt the normal biomechanics of the knee, including:

1. Anatomical variations: Such as a shallow trochlear groove or an abnormally high-riding patella
2. Muscular imbalances: Particularly weakness in the vastus medialis obliquus muscle
3. Ligament laxity: Especially in the medial patellofemoral ligament
4. Malalignment of the lower extremity: Including excessive knee valgus (knock-knees)

How do these factors contribute to knee instability?

These biomechanical issues can lead to patellar instability by:

• Reducing the natural restraints that keep the kneecap in place
• Altering the normal tracking of the patella within the trochlear groove
• Increasing the lateral forces acting on the patella during knee movement

Understanding these biomechanical factors is crucial for developing effective treatment and prevention strategies tailored to each patient’s specific condition.

The Role of Imaging in Diagnosing Patellar Instability

While a physical examination is often sufficient to diagnose acute patellar dislocations, various imaging techniques play a crucial role in assessing the extent of the injury and planning treatment. Common imaging modalities used include:

• X-rays: To evaluate bone alignment and rule out fractures
• CT scans: For detailed assessment of bone structure and trochlear groove anatomy
• MRI: To visualize soft tissue structures, including ligaments and cartilage

What specific information can these imaging studies provide?

Each imaging technique offers unique insights:

• X-rays can reveal patellar height and tilt
• CT scans help measure the trochlear groove depth and patellar engagement
• MRI can identify damage to the medial patellofemoral ligament and assess cartilage integrity

These imaging studies not only aid in diagnosis but also help surgeons plan the most appropriate intervention if conservative treatments prove ineffective.

The Impact of Patellar Instability on Athletic Performance

For athletes, patellar instability can have significant implications on performance and career longevity. The condition can affect:

• Confidence in knee stability during sports activities
• Ability to perform quick changes in direction or pivoting movements
• Overall agility and speed on the field or court
• Long-term joint health and risk of early-onset osteoarthritis

How can athletes manage patellar instability while maintaining performance?

Athletes dealing with patellar instability may benefit from:

• Sport-specific rehabilitation programs
• Customized knee bracing for added support during competition
• Technique modifications to reduce stress on the patellofemoral joint
• Regular strength and flexibility training to maintain optimal knee function

With proper management and a comprehensive approach to treatment, many athletes can successfully return to their sport following patellar instability episodes.

Psychological Aspects of Dealing with Recurrent Knee Instability

The psychological impact of patellar instability should not be overlooked. Patients with recurrent instability may experience:

• Fear of re-injury or dislocation
• Anxiety about participating in physical activities
• Frustration with ongoing symptoms or treatment requirements
• Depression related to limitations in daily life or sports participation

How can patients cope with the psychological challenges of patellar instability?

Strategies to address the mental health aspects of this condition include:

• Working with a sports psychologist or mental health professional
• Practicing mindfulness and relaxation techniques
• Setting realistic goals for recovery and gradual return to activities
• Joining support groups or connecting with others who have experienced similar injuries

Addressing both the physical and psychological aspects of patellar instability is crucial for achieving optimal outcomes and maintaining overall well-being.

Why My Knee Popped Out Of Place, Then Right Back In Again

What Is Patellar Instability?

Patellar instability is a condition in which your kneecap slides or moves out of its normal position within your trochlear groove, which is the groove that your kneecap sits on. This groove helps to stabilize your kneecap and keep it from sliding.

However, if you have patellar instability, the movement will result in an unstable kneecap and can even lead to a dislocated kneecap. The instability of your patellar may be classified as acute or chronic, depending on how frequently it occurs.

Acute instances generally occur in sports, specifically football, basketball, and volleyball. Young athletes whose ages range from 13-20 have the highest incidence rates. Additionally, due to anatomic issues, teenage females are at the highest risk of experiencing instability.

What Happens When My Knee “Pops” Out of Place?

You may wonder what happens when your knee “pops” out of place. Two things can happen. When your knee “pops” out of place, your patella may be “subluxated” or “dislocated,” depending on the degree of your patella instability.

A subluxation is a partial knee dislocation and occurs when your kneecap slightly shifts out of the groove and then “pops” back into place. A patella dislocation occurs if your patella moves entirely out of the groove and stays in that position.

Generally, when you bend or straighten your leg, your kneecap will move up and down in your trochlea groove. When it comes to patellar instability, your kneecap does not track the groove properly.

What Causes a Kneecap Dislocation to Happen?

The most common cause of a kneecap dislocation is a non-contact twisting injury when the knee joint is almost fully extended. Additionally, a direct blow to the kneecap while playing sports, a fall, or another form of accident can cause a partial or complete dislocation.

Dislocated Knee Symptoms

If you have a dislocated knee, you may experience the following:

• Severe pain
• Swelling
• Visible deformity
• Decreased range of motion (ROM)
• Tenderness in the area
• “Popping” sounds when you bend your knee or climb stairs

How Can a Dislocated Knee Be Diagnosed?

To ensure that an accurate diagnosis is made, your specialist will first review your medical history. They will also perform an apprehension test to assess your injury. Imaging tests, such as an X-ray, may also be ordered to provide your specialist with a diagnostic view to ensure that your patella has not been fractured.

It is important to note that even if your knee cap moves back into place on its own, you should still seek the assistance of a specialist so that they can accurately provide a diagnosis and treatment if needed. They can also verify that the surrounding muscles, ligaments, nerves, and blood vessels have not been injured.

Treatment Options for a Dislocated Knee

Because each circumstance and injury will vary, your orthopedic surgeon will determine whether non-surgical or surgical intervention is the best treatment for your knee pain.

The initial management of your injury may include swelling reduction, bracing to immobilize your knee joint, and possibly using crutches to assist in weight-bearing so that your knee will not buckle.

Additionally, physical therapy can also be beneficial to your recovery because it strengthens the muscles that hold your kneecap in place. During your physical therapy sessions, a physical therapist will also assist you in improving your range of motion.

If you have chronic instability or a complete kneecap dislocation, your specialist may recommend an arthroscopic procedure.

How Can I Prevent Patellar Dislocation From Reoccurring?

Naturally, you may wonder how to prevent patellar dislocation from reoccurring. Below you will find some helpful tips to guide you in preventing this from becoming a recurring event.

Helpful Strategies to Decrease the Recurrence of Knee Dislocation:

• Modifying your activities
• Stretching
• Quad-strengthening to keep your thigh muscles strong
• Bracing
• Using custom orthotics
• Maintaining a healthy weight

A dislocated knee, whether partial or complete, can be extremely painful. Schedule an appointment with one of our board-certified specialists at OrthoNeuro today to get relief from your knee injuries!

For your convenience, we have many offices located throughout Columbus, OH. Let us provide you with the relief you deserve!

Dislocated kneecap – NHS

A dislocated kneecap is where your kneecap (patella) moves out of place. It is usually caused by an injury to the knee. Get medical advice as soon as possible if you think you have a dislocated kneecap.

Urgent advice: Get help from NHS 111 if:

You’ve injured your knee and:

• it’s very painful
• it’s swollen or bruised
• you cannot stand up or move your knee
• you think your kneecap dislocated and then moved back into place

You can call 111 or get help from 111 online.

Immediate action required: Go to A&E if:

You’ve injured your knee and:

• your knee has changed shape
• it becomes very swollen very quickly
• you felt a pop or snap in your knee
• you can see bone sticking out of your skin
• it’s bleeding heavily

Call 999 if you’re unable to get to A&E.

While you are waiting for medical help

If you think you have dislocated your kneecap, there are some things you can do while waiting for treatment:

Don’t

• do not raise the affected knee

• do not try to stand or walk on the affected leg

• do not try to put the kneecap back into place yourself

Treatment for a dislocated kneecap

A dislocated kneecap often moves back into place by itself.

Even if it does, you will still need to get it checked by a doctor. You will usually need X-rays or an MRI scan.

If your kneecap does not go back into place by itself, a doctor may have to move it back. You will be given a local anaesthetic and may be offered a sedative so you do not feel any pain.

Surgery may be needed if you have badly damaged your knee. Some people may also need surgery to stop the knee from dislocating again.

After treatment, you’ll need to go to follow-up appointments to check your knee is healing properly.

Recovering from a dislocated kneecap

It can take 6 to 8 weeks to fully recover from a dislocated kneecap, but you will usually be able to walk using the affected knee within a few days.

You may be given a knee support to wear for 2 weeks to help it heal. If walking is painful, using a crutch may help.

Your doctor or a physiotherapist will show you knee exercises that you should do regularly to help speed up your recovery.

Things you can do to help your recovery

There are some things you can do to help with the recovery of a dislocated kneecap.

Do

• take painkillers like paracetamol or ibuprofen to help with pain

• keep your knee and lower leg slightly raised and supported when resting to reduce swelling

• do knee exercises throughout the day to stop your knee getting stiff

• stay as active as you can

Page last reviewed: 25 January 2023
Next review due: 25 January 2026

Habitual dislocation of the patella treatment in Zaporozhye clinic of orthopedics

By itself, dislocation of the patella occurs rarely, but with congenital anomalies of the knee joint or as a result of other traumatic injuries of the knee patellar dislocations occupy the second most common place among injuries of the knee joint. What does the prefix “usual” mean? She talks about the periodic recurrence of such trauma.

Patella dislocation causes

In order for the patella to displace, which we often call the patella, an enormous load on the leg is necessary. Therefore, most often the cause of this injury is excessively active sports and related falls on the knees, lateral blows to the knee (medial and lateral subluxation of the patella), sharp extension of the knee joint

When such an injury occurs, they speak of an acute condition. If after a while the patella moves again, this is a habitual dislocation of the knee joint. Often it occurs after the reduction of acute displacement of the patella.

Symptoms and signs

Acute trauma to the patella develops characteristic symptoms. The patient feels a sharp severe pain, the patella is visually displaced, swelling of the joint develops. Usually the leg is very painful and difficult to move – bend or straighten, so you should immediately consult a doctor.

Habitual dislocation of the knee causes less pronounced symptoms. The most common are pain in the knee joint and a feeling of instability in the knee (the knee seems to be unstable and is not fixed when moving).

Diagnosis of a dislocated patella

If symptoms occur, you should immediately contact an orthopedic traumatologist for a diagnosis. The fact is that similar manifestations can also talk about other problems with the knee, for example, a fracture of the patella. Therefore, after a full-time examination, a specialist can prescribe:

• radiography of the knee joint in several projections
• MRI of the knee is the most informative diagnostic method that will show, among other things, the condition of the ligaments and treat at the same time.

Dislocation of the patella and its consequences

Injury to the patella is a serious injury that should not be taken lightly. Without timely access to a specialist and accurately selected treatment, it can provoke other problems with the knee joint. For example, dislocation of the patella, even over time, often significantly limits activity: there is constant discomfort and a feeling of instability in the joint. Also, dislocations can be repeated periodically – in this case, they talk about the habitual dislocation of the patella, when even with minor physical exertion, the patella is displaced. Chronic damage to the patella will eventually burn to cause arthrosis (that is, destruction of the joint).

Is surgery necessary for a dislocated kneecap?

Primary patella dislocation is usually treated conservatively. If there is a habitual dislocation of the patella, more serious treatment is needed. However, for repeated dislocations, we recommend surgical treatment – using arthroscopic techniques.

Treatment of patellar dislocation in our clinic

The recommendation of our specialists is to perform knee surgery in case of habitual patellar dislocation. In our clinic, preference is given to low-traumatic arthroscopic methods of treatment (the operation is performed through several punctures). Thus, an orthopedic traumatologist performs manipulations inside the joint as accurately and at the same time sparingly: aligns and fixes the patella, sanitizes the articular cavity, and, if necessary, removes hematomas. Such treatment makes it possible to stop recurring dislocations and to prevent arthrosis.

Rehabilitation after dislocation of the patella

Since arthroscopy is a gentle surgical technique, the rehabilitation period does not last long. An experienced rehabilitation specialist monitors the recovery after treatment in our clinic. It is worth noting that the specialist starts working with patients the very next day after the operation in order to maintain the joint in good shape. A specialist for each develops an individual rehabilitation plan, exercise therapy and physiotherapy for a speedy recovery.

Hyaluronic acid injections or PRP therapy may also be given to improve joint function. These procedures help to improve the nutrition of the joint and speed up healing.

Knee injury: consequences and rehabilitation

Knee injury is one of the most common reasons people seek medical attention. First of all, professional athletes are at risk, as well as rollerbladers and cyclists, skiers, and snowboarders. Sometimes people get a knee injury as a result of a car accident.

For minor knee injuries, it is recommended to reduce physical activity and apply ice compresses. Severe injuries will require surgery and rehabilitation with the participation of a physical therapist. The most common types of knee injuries are: bruise, dislocation, knee fracture, sprain, meniscus tear.

Let’s talk about common injuries and rehabilitation methods.

Patient in physical therapy session

Broken knee

Any bone can be fractured in and around the knee, but the most common fracture is the patella, for example as a result of a fall or car accident. People with osteoporosis are at risk of fracture due to reduced bone density.

A displaced fracture may require surgery, but if the bone is in the correct position, it is enough to wear an orthopedic immobilizer (fixator) to keep the knee in the desired position, and also not to load the leg and wait patiently for recovery.

If the injury was caused by jumping and landing on a straight knee, then it is important to do not only an x-ray of the patella, but also a CT scan to make sure that the bones are not displaced, the fracture will not cause complications to the femur and will not lead to arthritis in the future and chronic pain.

Knee dislocation

Falls, contact sports and car accidents are the most common causes of knee dislocation. With it, one or more bones can be displaced from their natural position. A dislocation can damage the blood vessels and nerves around the knee and may require surgery. Displacement of the patella can be very painful, but easily reversible injury – you need to see a doctor to set the patella in place and apply a splint. Subsequently, a set of physiotherapeutic exercises developed by a specialist in a hospital or rehabilitation center is recommended.

Tendon rupture

Tendons are soft tissues that connect muscles to bones. In the event of a knee injury, the tendon of the kneecap is damaged. This injury can be obtained during sports and as a result of accidental falls. The elderly are also at risk.

If a person cannot lift their leg due to a torn tendon, they should see a doctor as soon as possible. You may need to do an x-ray and an MRI. If they confirm the rupture, then surgery will be required, after which a plaster is installed. Recovery can be lengthy and should be supervised by an orthopedic surgeon and a physical therapist.

Injury to the meniscus

The meniscus is a small piece of cartilage that acts as a shock absorber in the joint, so if it is damaged, the knee loses stability. A meniscus injury is characterized by inability to flex and straighten the leg, difficulty going up and down stairs, and a characteristic click can be heard when the knee moves. Athletes and dancers know a lot about meniscus damage – this is one of the most common injuries.

A meniscal tear can be identified using X-ray and MRI. Damage may require arthroscopy or surgery. A torn meniscus may require surgery to remove it. When displaced, the orthopedic doctor sets the meniscus in place and puts a plaster or splint, after which physiotherapy is necessary.

There are also degenerative lesions of the meniscus caused by the aging process. Then the injury can be obtained when performing simple exercises: squats, getting up from your haunches, or even in a dream. Treatment and rehabilitation for degenerative lesions should be discussed with an orthopedic and physical therapist.

Tendonitis

This is an inflammation of the tendon that connects the lower leg and the kneecap. Athletes, especially runners, are most at risk, as the cause of tendinitis is constant overexertion and microtrauma. Tendinitis is characterized by pain when pressing on the ligaments and sharp pain during peak exercise during sports. For treatment, you will first need to give up sports, then relieve inflammation with the help of medications, take a course of therapeutic exercises. In special cases, surgery may be needed to remove diseased tissue.

General symptoms

Pain characteristics and intensity may depend on the type of knee injury. But there are symptoms that you should pay attention to in all cases of injury:

• Swelling of the knee,
• Inability to bend or straighten the knee,
• Cracking in the knee,
• Visible bone deformity,
• Increased temperature in the knee,
• Difficulty in carrying weights,
• Constant aching and non-recurring sharp pain,
• Loss of sensation in the knee area.

When to see a doctor

If your symptoms are as described above and first aid and home care do not help, you should see a doctor.
Urgent care is needed immediately after an injury to prevent complications, and in situations of severe swelling and fever in the knee area, which may be an indicator of infection. This is especially important for people with weak immune systems, children, and people who have had previous knee surgery.

An initial examination can be performed by a general practitioner. To make an accurate diagnosis, it is worth contacting a surgeon and an orthopedist. To determine the nature of the injury, the doctor examines the knee and palpates, revealing pathologies. An x-ray may be needed to assess the nature of the injury. An MRI is needed if there is a suspicion of ligament and meniscal injury. Physiotherapists will ensure an effective rehabilitation process.

Risk factors

Factors that increase the risk of knee injury:

• Overweight. Increases stress on the knee joints even during normal activities such as walking or going up and down stairs. It also increases the risk of developing osteoarthritis by destroying articular cartilage.

• Lack of muscle flexibility. Strong and toned muscles help stabilize and protect joints, while muscle flexibility increases range of motion and thus reduces the risk of meniscus injury.

• Some sports. Alpine skiing, basketball, jogging require more stress on the knees than other sports. If you play these sports, it is worth checking regularly with your doctor.

• Previous injury. Having a previous knee injury increases the chance of getting a new one.

The recovery process

The goal of knee treatment and recovery is to return the person to their level of activity and quality of life as they were before the injury. The prognosis for recovery is always individual and depends on the type of injury, as well as the amount of exercise performed.