Knee – Side View
Anterior knee pain is pain that occurs in the front and middle of the knee. The reason for this could be due to several circumstances:
- Patellofemoral pain syndrome
- Chondromalacia Patellae
- Osgood-Schlatter’s disease
- Sinding Larsen Johansson syndrome
- Plica synovialis syndrome
- Knee bursitis/Hoffa’s disease
- Articular cartilage injury
- Bone tumors: Most patients experience pain in the area of the tumor. The pain becomes worse during physical activity and often wakes the patient during the night. The bone mass around the tumor weakens, and fractures may result as a result. 
- Osteochondritis dissecans
- Patellafemoral instability/subluxation
- Patella Stress Fractures: Stress fractures in the patella result from fatigue from submaximal stress loads or bone insufficiency previously weakened by physiological stress. It reduces shock absorption so high repetitive loads can cause stress fracture. 
- Patellar tendinitis
- Patellofemoral osteoarthritis
- Goosefoot Bursitis: Goosefoot bursa is one of 13 bursae found around the knee joint, under the foot of the goosefoot. Patients with anserine foot bursitis often complain of spontaneous knee pain with tenderness in the lower medial aspect of the knee joint. 
- Quadriceps tendinopathy
- Prepatellar bursitis
- Iliotibial band syndrome 
The etiology of anterior knee pain is multifactorial and not well-defined due to the variability in symptomatic pain location and pain intensity experienced by patients. An underlying factor could be an abnormality of the patella, muscle imbalance, or weakness that leads to misalignment of the patella in flexion and flexion postpone. Possible causes include overuse injuries such as; tendinopathy, insertional tendinopathy, patellar instability, cartilage and osteochondral injury .
Anterior knee pain is not well defined  as patients may present with various symptoms. There may be functional deficits crepitus and/or instability. Pain that often occurs or worsens when going downstairs, squatting, and pressing the car clutch pedal with the activities of daily living Wearing high heels or sitting for long periods of time with bent knees is known as the “movie sign.” Patients may also experience some degree of instability, especially when going up and down stairs or ramps . People with overuse injuries may report a feeling Instability or submission, although this may not be true submission (associated with internal knee injury) but rather neuromuscular inhibition due to pain, muscle weakness, patellar or joint instability 
- Referral pain caused by femoral epiphysis and other hip joint lesions
- Referral pain from the saphenous nerve 
Assessment of anterior pain is challenging because it can be nonspecific and the differential diagnosis is broad. It requires a thorough examination of the history of symptoms, an in-depth knowledge of the structures involved and typical patterns of injury. In young people, assessing their general growth Development is also essential to confirm the diagnosis.
Hip and lumbar diseases can refer to the knee and need to be ruled out.
Some of the key factors to get an accurate diagnosis are; pain profile i.e. its site specific onset duration changes with activity or rest aggravating and mitigating factors and any nocturnal pain; trauma (short/long term acute major trauma repetitive microtrauma); mechanical symptoms (locking or expanding mass instability worse during or after activity); inflammatory symptoms such as morning stiffness swelling; effects of previous treatments and patient’s current level of function: whether there is any gout pseudogout rheumatoid arthritis or other degenerative disease history joint disease. Selective use of appropriate imaging techniques, such as ultrasound and MRI, are excellent tools for differential diagnosis and exclusion of sources of intra-articular disturbance 
Diagnosing and thus choosing an individual-specific non-surgical treatment option can be frustrating. The European Rehabilitation Group has developed a guideline that should improve treatment options and outcomes. They recommend the following evaluation parameters:
- Symptoms: Pain (location and type) or instability issues?
- Alignment of the entire lower extremity: strabismus patella? High Q angle? Knee valgus? Anti-knee? Subtalar joint pronation?
- Patella position: high patella? Lower patella? Patella slip? Patella tilt? Patella rotation?
- Muscle and Soft Tissue: Malnutrition for VMOs? Imbalance between VM and VL? Weak knee extensors, hip flexors, and/or hip abductors? How tight is the medial retinaculum? Tightness of the lateral musculature hamstring and/or rectus femoris?
- Knee function (patella pain and/or poor kinematics): during different dynamic activities such as stair ascending/descending exercises and single leg squats?
The 13-item screen of the Kujala Anterior Knee Pain Scale (AKPS)  can also be used to identify patellofemoral pain in adolescents and young adults . Ittenbach et al agree that this is highly reliable, but not without limitations, and further research is needed before it can be used outside of the clinic environment and application to the general population . AKPS has shown good test-retest reliability.
The Lower Extremity Function Scale (LEFS) is a further self-report test to assess the difficulty patients experience with activities. The questionnaire was less specific for patients with anterior knee pain than the Anterior Knee Pain Scale. LEFS also demonstrates high test-retest reliability and It is slightly more reliable and responsive than AKPS 
The Kujala Anterior Knee Pain Scale and Lower Extremity Function Scale can be used both as an initial screening tool and to detect post-treatment changes and outcome measures.
Single-leg squats are also used to assess pain in the front of the knee.
In the presence of bony abnormalities or retinaculum dysfunction, nonoperative management may be less successful, but surgical management should be reserved for patients with correctable anatomical abnormalities for whom conservative management has failed 
Physical Therapy Management
For long-term nonsurgical results, any postural misalignment or altered movement patterns should be addressed first before introducing an intensive program. When assessing functional abnormalities and compensatory patterns, the entire lower extremity should be viewed rather than limiting the assessment to the knee area. Any significant leg length differences as well as inherent imbalances in the foot that are contributing factors should be addressed. Eng et al have both shown that orthotics and exercise can lead to more effective outcomes for patients with knee anterior pain than exercise Exercise alone , but any exercise and/or stretching program needs to be individualized based on the symptoms and motor deficits present.
 Too tight a retinaculum can affect the patellofemoral joint, and manual stretching or McConnell taping may improve symptoms. However, taping alone did not significantly reduce pain. However, there is evidence that combining knee taping, including placebo taping, with exercise provides better results. Less pain than exercise alone. Therapies such as proprioceptive insoles and taping work best as a supplement to traditional exercise therapy; however, they are not effective alone.  Improving eccentricity through an exercise program Muscle control is more effective than concentric exercises, and closed-chain exercises are more practical and minimize stress on the patellofemoral joint.  Weakened knee extensor strength is common in patients with anterior knee pain and weakness of the vastus medialis oblique muscle (VMO) Although Witvrouw et al. concluded that VMO does not work in isolation , exercises designed with VMO activate both VM and VL. Neuromuscular dysfunction is thought to be the cause of VMO deficits. The muscle length of the hamstrings, gastrocnemius and rectus femoris both affect the patellofemoral joint mechanics. Quadriceps movements require more force, so tight hamstrings increase patellofemoral reaction forces, so regular stretching is recommended. But according to Mason et al., who compared the effectiveness of quadriceps stretches with Strengthening and taping in isolation and combining quadriceps stretching and quadriceps strengthening resulted in more improvement in isolation than taping. They also concluded that a combination of these treatments is recommended as an initial approach to patellofemoral pain, but further A more practical and individualized holistic treatment is essential.  Presentation Case Study: Anterior Knee Pain in Adolescents This presentation was created by Omolara Ajayi in collaboration with: EIM Clinical Excellence Network and Physiotherapy Center. View Presentation Clinical Bottom Frontal knee pain is a symptom, not a diagnosis. Any diagnosis of pain is essentially by exclusion, as there are many possible conditions in which patellar abnormalities or muscle imbalances are important factors to identify through a thorough history and patient examination. there is another high There is a correlation between AKP and defective hip mechanics, so any assessment needs to address the entire kinetic chain. Treatment is highly individualized, and the European Rehabilitation Group guidelines are useful tools for selecting non-surgical treatment options.
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