Patellofemoral Pain Syndrome - Types, Causes, Diagnosis and Treatment

Introduction

Patellofemoral pain syndrome, abbreviated as PFPS, is colloquially called runner’s knee or jumper’s knee. It is a condition that causes painful symptoms in the region under and around the patella or kneecap. The condition can affect one or more knees in children and adults. The pain worsens with prolonged sitting with bent knees or intense activity without rest.

Who Are Predisposed to Develop Patellofemoral Pain Syndrome?

Aging females, athletes, children, and young adults are most prone to developing patellofemoral pain syndrome. Sports involving frequent running, jumping, or squatting, and aging people walking, sitting, kneeling, or climbing stairs for prolonged durations are also naturally predisposed to develop this condition.

What Are the Underlying Causes Behind Patellofemoral Pain Syndrome?

The precise etiology behind patellofemoral pain syndrome is currently obscure; however, several conditions have been identified that may either trigger it or aggravate pre-existing pain, enlisted as follows;

• The repetitive and vigorous strain on the knee joint.

• Malaligned or dislocated patella.

• Anatomical variations.

• Muscle weaknesses around the knee joint.

• Improper training techniques during athletics or exercise.

• Footwear-related issues.

• Playing surfaces that are hard and cause regular impacts.

What May Be the Symptoms Experienced By a Patient Suffering from Patellofemoral Pain Syndrome?

The symptoms generally appear progressively and may exacerbate as the intensity and duration of the exercise increase. Patients usually complain of a dull, aching type of pain in front of the affected knee, along with the following symptoms;

• Pain on bending the knee.

• Pain during extended periods of squatting.

• Pain on frequent climbing of stairs or walking on uneven ground.

• Crackling or popping sounds in the kneecap.

• Aggravated pain due to changes in playing surface, sports equipment, or activity intensity.

When to See the Doctor?

If the aforementioned symptoms persist and aggravate, and they are not being managed by massage, therapy, or medication, a specialist consultation to diagnose the condition is highly recommended.

What Is the Diagnosis of Patellofemoral Pain Syndrome Based Upon?

The consulting specialist carefully considers the patient’s symptoms and then performs a physical examination. Diagnostic imaging tests may also be performed to rule out alternative causes, such as patella sprains, fractures, or dislocations.

What Are the Nonsurgical Treatment Modifications for Patellofemoral Pain Syndrome?

The treatment typically does not involve surgery, and the extent and severity of the symptoms determine the therapy. The RICE protocol, which is described as the first line of treatment, is as follows;

• Rest: Applying weight to the knee joint must be avoided.

• Ice: Apply ice packs for several minutes a day. Direct skin contact should be avoided.

• Compression: An elastic bandage wrapped snugly around the affected area may be useful. However, care must be taken to prevent blood flow from obstructing the area. It must also be noted to ensure the bandage does not aggravate the pain.

• Elevation: The affected knee should be elevated and raised above the level of the patient’s heart.

In addition to home remedies, other treatment modalities may include the following;

• Physiotherapy: A physical or occupational therapist may advise certain strengthening exercises to prevent further aggravation and, if possible, heal the affected area.

• Orthotics: These orthopedic devices are designed as removable footwear to help reduce the stress on the lower limbs.

• Other: If the modalities above fail, surgical options must be considered.

What Are the Surgical Treatment Modalities Employed to Treat Patellofemoral Pain Syndrome?

Surgical techniques to treat patellofemoral pain syndrome may include the following;

• Knee replacement surgeries.

• Knee reconstruction surgeries.

What Is Knee Replacement Surgery?

Knee arthroplasty, another name for a knee replacement, is a better description because only the surface of the bone needs to be replaced.

The steps involved in knee replacement surgery are listed below:

• Positioning the Metal Implants: By replacing the bone and cartilage with metal, either cemented or uncemented, components, the joint surface is reproduced.

• Bone Preparation: The femur and tibia damaged cartilage surfaces are removed.

• Resurfacing the Patella: A plastic button resurfaces the area below the kneecap, albeit only sometimes necessary. To provide a smooth gliding surface, a medical-grade plastic spacer is put between the metal parts.

What Is Knee Reconstruction Surgery?

• Knee reconstruction surgeries are typically performed either under general or spinal anesthesia.

• First, an incision is made on the skin of the affected joint's surface. The damaged portion of the bone or cartilage is then removed, and suitable grooves are created to house the implants necessary.

• Following this, the implants are stabilized using either screw plates or cement. A plastic liner insert is placed between the two articulating bone surfaces to act as the cartilage. In the case of ligament reconstruction surgeries, the hamstring tendon is used as a graft, coupled with drilling holes in appropriate places of the knee joint surfaces, then pulled through it.

• This is followed by stabilization, using screws or plates, and suturing to allow healing of the cartilage into the bone.

How Is Rehabilitation Done Postoperatively?

A comprehensive rehabilitation program should be included in the treatment of PFPS. The first stage is control of active symptoms (activity modification, nonsteroidal anti-inflammatory drugs, application of ice, patellar taping, or bracing). Active stretching exercises, squats, ergometers, static quadriceps exercises, active leg raises, leg presses, and raising and lowering climbing exercises have all resulted in positive outcomes. Prosthetic devices such as a walker, crutches, or cane may be prescribed until the joint regains functionality. A continuous passive motion (CPM) machine may passively move the joint while the patient relaxes. An exercise program at home will also be prescribed to maintain joint functionality.

How to Prevent Patellofemoral Pain Syndrome?

Patellofemoral pain syndrome can be prevented by:

• Maintaining a healthy body weight.

• Warming up before physical activity.

• Increasing one’s activity gradually.

• Stretching before and after physical activity.

• Wearing appropriate shoes for physical activities.

• Running, leaning forward with the knees bent.

Conclusion

Patellofemoral pain syndrome is a clinical entity that causes anterior knee pain in the anterior knee without any noticeable pathological changes in the patellofemoral joint cartilage. A functional malalignment or dynamic valgus may be the underlying cause of patellar maltracking. Dynamic valgus can be caused by reduced hip abductor strength or a pes pronatus valgus. Quadriceps disbalance, hamstring tightness, or iliotibial tract tightness are all symptoms of functional malalignment of this disease. The clinical significance of these findings is that they allow a physician to tailor an individual treatment plan for each patient based on the underlying pathology. Purchasing a cold therapy machine is recommended by healthcare professionals to relieve the pain associated with patellofemoral pain syndrome.