Patellar Chondropathy: Symptoms, Exercises, and Treatment

Patellar chondropathy

Patellar chondropathy (or chondromalacia patellae) is a condition characterized by the deterioration of the cartilage lining the posterior surface of the patella, the bone structure that glides in the femoral trochlea during knee flexion and extension movements. It is one of the most common causes of anterior knee pain, especially in young adults and athletes.

Typical pain from patellar chondropathy occurs when climbing or descending stairs, getting up from a prolonged seated position, squatting, or running downhill. It is closely related to patellofemoral pain syndrome (PFPS), with which it shares causes, symptoms, and treatment.

Physiotherapy and specific exercises are the first-line treatment, with excellent results in the majority of cases.

Table of Contents

• Anatomy: The Patellofemoral Joint
• Stages of Patellar Chondropathy
• Causes
• Symptoms
• Diagnosis
• Treatment
• Exercises for Patellar Chondropathy
• Recovery Times
• When Is Surgery Necessary?
• Prevention
• Frequently Asked Questions (FAQ)
• Frequently Asked Questions
• Sources and Scientific References

Anatomy: The Patellofemoral Joint

The patella is a sesamoid bone (the largest in the body) located within the quadriceps tendon. Its function is to increase the lever arm of the quadriceps, improving the efficiency of knee extension by 30-50%.

The posterior surface of the patella is covered by very thick cartilage (up to 7 mm — the thickest in the human body), necessary to withstand the enormous pressures that develop between the patella and the femur:

• On flat ground: the patella experiences a force equal to 0.5 times body weight
• Climbing stairs: approximately 3-4 times body weight
• Deep squat: up to 7-8 times body weight

The patella glides in the femoral trochlea — a groove on the anterior surface of the femur — guided by the quadriceps, patellar tendon, and medial and lateral capsuloligamentous structures. Patellar maltracking (abnormal gliding) in the trochlea is one of the main causes of chondropathy.

Stages of Patellar Chondropathy

Outerbridge’s arthroscopic classification distinguishes four grades:

Grades I and II are the most common in young people and are generally reversible with conservative treatment. Grades III and IV represent more advanced degeneration.

Causes

Patellar Maltracking

The most frequent cause is the alteration of patellar tracking in the femoral trochlea. Instead of gliding in the center of the trochlea, the patella tends to lateralize (shift outwards), increasing pressure on the lateral facet of the patella and causing cartilage deterioration.

Causes of maltracking include:

• Weakness of the vastus medialis obliquus (VMO): the muscle that “pulls” the patella inwards, counteracting the lateral pull of the vastus lateralis
• Excessive tension of the lateral retinaculum: the lateral structures “pull” the patella outwards
• Stiffness of the iliotibial band: pulls the patella laterally
• Increased Q angle: a larger angle between the quadriceps and patellar tendon (more frequent in women due to pelvic conformation) predisposes to lateralization

Mechanical Overload

• Sports with repetitive loads on the knee: running, cycling with a saddle too low, jumping, heavy squats
• Sudden increase in training volume: programming errors
• Activities with prolonged flexion: kneeling, squatting

Predisposing Factors

• Female sex: 2:1 ratio, due to pelvic conformation and increased Q angle
• Pronated foot: alters lower limb biomechanics and increases internal tibial rotation, favoring maltracking
• Gluteal weakness: insufficiency of the gluteus medius causes dynamic knee valgus (knee “collapsing” inwards) during running and stairs
• Stiffness of the quadriceps and hamstrings: limit mobility and alter pressures on the patella
• Trochlear dysplasia: a shallow femoral trochlea predisposes to patellar subluxation

Symptoms

Anterior Knee Pain

• Location: pain in the anterior part of the knee, around and behind the patella
• Worsening: with stairs (especially downhill), squatting, crouching, running downhill, cycling with a low saddle
• “Cinema sign”: pain that appears after maintaining the knee bent for a prolonged period (at the cinema, in the car, at a desk), which improves by extending the leg
• Pain upon standing: pain when getting up from a chair after a prolonged seated position

Crepitus

Crepitus and cracking sounds felt under the patella during knee flexion and extension, especially during squatting and stairs. Crepitus is very common and often causes unnecessary alarm: it is not indicative of severity.

Swelling

Mild anterior knee swelling may be present after strenuous activities.

Sensation of Giving Way

In some cases, the knee may give a sensation of “giving way” or instability, due to quadriceps weakness or an episode of patellar subluxation.

Diagnosis

Clinical Examination

• Patellar palpation: pain on pressure over the patellar facets (medial and lateral)
• Patellar compression test (Clarke test): the doctor compresses the patella against the femur while the patient contracts the quadriceps — positive if it reproduces the pain
• Grind test: lateral movement of the patella — reproduces crepitus and pain
• Apprehension test: lateral displacement of the patella — positive if the patient feels discomfort or fear of subluxation
• Assessment of patellar tracking: observation of patellar glide during flexion-extension
• Assessment of lower limb alignment: valgus, pronated foot, Q angle

Imaging Diagnostics

• X-ray: axial patellar view (sunrise view) to assess lateralization, tilt, and trochlear dysplasia
• MRI: visualizes the condition of the patellar and trochlear cartilage, the degree of chondromalacia
• Ultrasound: can show effusion and retinacular alterations

Treatment

Fundamental Principles

Treatment is always conservative as a first approach, with success rates of 80-90%. The pillars are:

• Strengthening of the vastus medialis obliquus (VMO): to restore correct patellar tracking
• Gluteal strengthening: to control dynamic knee valgus
• Stretching: of the quadriceps, hamstrings, and iliotibial band
• Patellar taping: to reposition the patella and reduce pain during exercises

Physiotherapy

• Therapeutic exercises: the core of the treatment
• McConnell taping: the physical therapist applies a rigid tape that repositions the patella medially during activities — reduces pain and allows exercise performance
• Manual therapy: patellar mobilization, lateral retinacular release
• Orthotics: if a pronated foot is present, to correct lower limb alignment
• Patellar brace: with a central hole that centers the patella

Medications

• Topical NSAIDs (gel) applied to the patella
• Oral NSAIDs for short periods during flare-ups
• Ice after activity

Exercises for Patellar Chondropathy

The exercise program focuses on strengthening the VMO and glutes, stretching lateral structures, and controlling dynamic valgus. Your physical therapist will guide the progression.

Fundamental principle: closed kinetic chain exercises (foot on the ground) are preferable to open kinetic chain exercises (foot in the air) for the patella, because they better distribute forces on the patellofemoral joint.

VMO Strengthening

Mini squat (0-30°)

[IMAGE: Person standing with feet shoulder-width apart. Knees slowly flex only 20-30 degrees (mini squat), keeping weight on heels and knees aligned with toes. Torso remains upright. Side view with detail of the limited knee flexion angle. An arrow indicates the small range of flexion.]

Selective VMO contraction

[IMAGE: Person sitting on a chair with the knee slightly bent (about 20 degrees). A rolled towel is placed under the knee. The patella is observed as the patient contracts the quadriceps, pressing the knee downwards. The hand is placed on the vastus medialis (inner part of the knee, just above the patella) to feel the contraction. Front view with detail of hand position on the VMO.]

Controlled eccentric step-down

[IMAGE: Person standing on a step (15-20 cm) with the foot of the involved side on the step. The other leg hangs freely to the side of the step. The knee of the leg on the step slowly flexes (eccentric) until the heel of the other leg almost touches the floor, then returns up. The knee remains aligned with the second toe of the foot. Front view with detail of knee alignment.]

Gluteal Strengthening

Clamshell with resistance band

[IMAGE: Person lying on their side with knees bent at 45 degrees, a resistance band placed just above the knees. The upper knee lifts against the resistance of the band while keeping the feet in contact. The upper hand is on the hip to ensure the pelvis does not rotate. Front view with detail of the band and knee opening.]

Lateral lunge with valgus control

[IMAGE: Person standing, performing a lateral step to the right, bending the right knee. The right knee remains aligned with the second toe of the foot (does NOT collapse inwards). The left leg is extended. Front view with a vertical line highlighting knee-foot alignment.]

Stretching

Quadriceps stretch

[IMAGE: Person standing, grasping their ankle behind them, bringing the heel towards the glute. The knee is kept close to the other knee. The hand rests on a support. Side view with detail of the flexion angle.]

Iliotibial band stretch

[IMAGE: Person standing with legs crossed (the leg of the side to be stretched is behind). The torso leans laterally in the opposite direction to the side being stretched. The stretch is felt along the outer side of the thigh. Front view with detail of the lateral lean.]

Hamstring stretch

[IMAGE: Person standing with one foot on a low step, leg extended and toes pointing upwards. The torso leans forward with a straight back. The stretch is felt in the back of the thigh. Side view.]

Recovery Times

When Is Surgery Necessary?

Surgery is indicated only in cases that do not respond to 6-12 months of adequate physiotherapy. Options include:

• Lateral retinacular release: arthroscopic section of the retinaculum to reduce lateral traction
• Patellar realignment: procedures that modify the insertion of the patellar tendon to center the patella
• Chondroplasty: smoothing of damaged cartilage (limited results)

Prevention

• Quadriceps and gluteal strengthening: regular program 3 times a week
• Stretching: quadriceps, hamstrings, iliotibial band
• Gradual load progression: avoid sudden increases in running volume or squats
• Appropriate footwear: shoes with good cushioning, orthotics if pronated foot
• Correct technique: in squatting, running, cycling (correct saddle height)
• Avoid prolonged sitting: if at the computer, periodically extend the knees

For further information, consult the Complete Guide to Knee Pain and the article on runner’s patellofemoral pain syndrome.

Frequently Asked Questions (FAQ)

Does patellar chondropathy heal?

Grades I and II are generally reversible with conservative treatment. Softened cartilage can recover its properties with the restoration of correct patellar mechanics through muscle strengthening. Grades III and IV represent more significant structural damage, which can be managed but not completely reversible.

Can I run with patellar chondropathy?

Running can be gradually resumed once pain is under control and the quadriceps is sufficiently strengthened. Resumption must be progressive: start with short runs on flat ground, avoid downhills and uneven terrain. Your physical therapist will guide your return to running.

Is knee crepitus serious?

Crepitus behind the patella is very common and not necessarily indicative of severity. Many people with “noisy” knees have no pain or functional problems. If crepitus is accompanied by pain, swelling, or functional limitation, an evaluation is advisable.

Is patellar chondropathy the same as knee osteoarthritis?

Not exactly. Patellar chondropathy affects the cartilage of the patella (patellofemoral joint), while knee osteoarthritis more commonly affects the femorotibial compartment (between the femur and tibia). Patellar chondropathy is more frequent in young people, knee osteoarthritis in those over 50. However, advanced patellar chondropathy (grade IV) is, in fact, osteoarthritis of the patellofemoral compartment.

Does patellar taping work?

Yes, McConnell taping (rigid tape that medializes the patella) is supported by scientific evidence. It reduces pain during activities and allows strengthening exercises to be performed with less pain. It is not a definitive treatment but an aid during rehabilitation. Your physical therapist will teach you the correct application.

Is cycling good or bad for patellar chondropathy?

Cycling can be an excellent activity for patellar chondropathy if the saddle is at the correct height. A saddle that is too low increases patellofemoral pressure and worsens symptoms. The general rule: with the foot on the pedal at its lowest point, the knee should be slightly bent (about 25-30 degrees of flexion). Cycling strengthens the quadriceps with low joint impact.

Frequently Asked Questions

What is patellar chondropathy?

Patellar chondropathy is a condition characterized by the deterioration of the cartilage lining the posterior surface of the patella, or kneecap. This deterioration can lead to anterior knee pain, particularly during movements that involve knee flexion and extension.

What are the primary causes of patellar chondropathy?

This condition frequently arises from the kneecap not tracking correctly within the femoral groove, often due to muscle imbalances or tightness. Mechanical overload and certain predisposing factors can also contribute to the development of cartilage deterioration.

How is patellar chondropathy typically diagnosed?

Diagnosis usually involves a comprehensive clinical examination by a healthcare professional, assessing symptoms and knee mechanics. Imaging diagnostics, such as X-rays or MRI, may be utilized to confirm the extent of cartilage changes and rule out other conditions.

What is the role of physical therapy in managing patellar chondropathy?

Physical therapy is a cornerstone of treatment, focusing on improving patellar tracking and reducing pain through specific exercises. A physical therapist designs individualized programs to strengthen supporting muscles, improve flexibility, and modify activities.

For a broader overview of related conditions, see our our comprehensive knee pain guide.

Sources and Scientific References

1. Kamat Y et al. (2022). Patellofemoral joint degeneration: A review of current management. J Clin Orthop Trauma. 24:101690. DOI | PubMed
2. da Costa SR et al. (2021). The role of viscosupplementation in patellar chondropathy. Ther Adv Musculoskelet Dis. 13:1759720X211015005. DOI | PubMed
3. Bakhtiary AH et al. (2008). Open versus closed kinetic chain exercises for patellar chondromalacia. Br J Sports Med. 42:99-102; discussion 102. DOI | PubMed
4. Arnoldi CC (1991). Patellar pain. Acta Orthop Scand Suppl. 244:1-29. DOI | PubMed
5. Mau H (1980). [Chondropathia patellae]. Z Orthop Ihre Grenzgeb. 118:208-18. DOI | PubMed