Anterior Knee Pain Causes, Symptoms, Diagnosis, Treatment, Prevention

Anterior Knee Pain Causes, Symptoms, Diagnosis, Treatment, Prevention


What Is Anterior Knee Pain?


Anterior knee pain is a characterized by a chronic pain over the front and centre of the knee joint.  It is common in athletes, active adolescents (especially girls) and overweight individuals. Anterior knee pain refers to a variety of conditions which include runner’s knee or patellar tendinitis and chondromalacia of the patella. There is an inter-individual variation in the duration and presentation of pain.

The knee joint is a large, complex joint in the body comprising of three bones, i.e. the lower end of the thigh bone or femur, upper end of the shinbone or tibia, and the kneecap or patella. The patella moves over the joint and allows bending of the knee and straightening of the leg. There are a few major ligaments situated around the knee joint which hold the joint firmly in position and contribute to the stability of the knee.

Anterior Knee Pain Causes


Patellofemoral pain syndrome


Patellofemoral pain syndrome is defined as pain behind or around the patella, caused by stress in the patellofemoral joint. Patellofemoral pain syndrome is common. Symptoms are usually provoked by climbing stairs, squatting, and sitting with flexed knees for long periods of time.

Patellofemoral pain syndrome seems to be multifactorial, resulting from a complex interaction between intrinsic anatomy and external training factors. Pain and dysfunction often result from either abnormal forces or prolonged repetitive compressive or shearing forces between the patella and the femur.

Patellofemoral pain syndrome is a common cause of knee pain in adolescents and young adults, especially among those who are physically active and regularly participate in sports. Although Patellofemoral pain syndrome most often presents in adolescents and young adults, it can occur at any age. Over half of all cases are bilateral (but one side is often more affected than the other).

The potential causes of Patellofemoral pain syndrome remain controversial but include overuse, overloading and misuse of the patellofemoral joint. Underlying causes of Patellofemoral pain syndrome include:

  • Overuse of the knee - eg, in sporting activities.
  • Minor problems in the alignment of the knee.
  • Foot problems - eg, flat feet.
  • Repeated minor injuries to the knee.
  • Joint hypermobility affecting the knee.
  • Reduced muscle strength in the leg.
Physiotherapy and foot orthoses are often used in the management of Patellofemoral pain syndrome.

Other common causes of anterior knee pain in adolescents

Osgood-Schlatter disease

Sinding-Larsen-Johansson disease - another common cause of anterior knee pain in children and adolescents. It is similar to Osgood-Schlatter disease but occurs at the inferior pole of the patella.

Osgood-Schlatter and Sinding-Larsen-Johannson diseases are common causes of anterior knee pain which are aggravated by jumping and kneeling.

Chondromalacia patella

Softening of the articular cartilage of the patella. This is therefore a pathological diagnosis and confirmation of chondromalacia patella requires MRI or arthroscopy.

There is a poor correlation between the degree of anterior knee pain and cartilage damage.
It may be associated with patellar misalignment.

Bipartite patella

This is common in adolescence and may cause pain and tenderness.

It is usually asymptomatic but variable in severity and may require surgical treatment.

Patellar misalignment

Often accompanied by damage to the chondral surface of the patellofemoral joint.

It is more common in girls and may cause recurrent dislocation or subluxation of the patella.

Hypermobility

Causes hyperextension and hyperflexion of the knee.

This most often presents around the time of the pubertal growth spurt.

Other common causes of anterior knee pain in adults


Patellar tendinopathy (jumper's knee)

Patellar tendinopathy is a common and painful overuse disorder.

Bursitis

Prepatellar bursitis (housemaid's knee).

Deep infrapatellar bursitis (parson's knee): inflammation is below the patella.

Anserine bursitis: often presents with spontaneous medial knee pain with tenderness in the inferomedial aspect of the joint.

Isolated patellofemoral arthritis

Patellofemoral osteoarthritis is a common form of knee osteoarthritis in middle and older age.


Symptoms of anterior knee pain


Pain is the predominant symptom and is usually gradual in onset. Patients may experience a dull aching pain around the sides, below or behind the knee cap. Sometimes, climbing stairs and standing up or walking after prolonged sitting may produce a popping or cracking sound in the knee. The pain may also be present at night and be exaggerated by any repetitive knee bending activity such as jumping, squatting, running or weight lifting. Any changes in the activity level, playing surface or equipment may also result in pain.

The pain is generally aggravated by activity and reduced by relaxation. The pain may worsen until it persists even when you are doing no activity.

Diagnosing Anterior Knee Pain

 
Your GP or Physiotherapist can usually diagnose an Anterior Knee Pain by simply examining your knee and hearing where the pain is and how it started.
 
X-rays and other tests are not usually necessary.

Treatment for Anterior Knee Pain


The main method of treating anterior knee pain involves initially rest, physiotherapy and occasionally medications.

Rest


Avoiding activities (such as squatting, jumping and stair climbing) where the knee is flexed into deep flexion can help settle your pain more quickly. Your surgeon will instruct you on proper techniques to reduce the pressure on the knee and alleviate symptoms whilst doing some bending activities.

Physiotherapy


As your pain improves, you will need to rehabilitate your knee to regain its motion, improve the strength of the muscles at the front of the knee and also improve your flexibility. This will not only speed up your recovery but will reduce the chances of your pain returning in the future.

The surgeons at SKS will often refer you to a physiotherapist for this rehabilitation to occur. The main focus of treatment is improving the muscle strength of the inner portion of the quadriceps muscle - the vastus medialis obliquis (VMO). This muscle is extremely important in helping maintain the patella in the trochlear groove of the femur bone. As your strength increases, this muscle helps alleviate some of the forces that the patella experiences as it moves into the trochlear groove.

It is important that this muscle is strengthened in a non-painful manner and your surgeon and physiotherapist will give you appropriate exercises for this. Additionally your physiotherapist will focus on improving your hamstring flexibility (muscles at the back of your thigh) as tight hamstrings can place significant forces on the patella. There is a tendon on the outer aspect of the thigh called the iliotibial band (ITB) which may also be tight, producing pain. Improving flexibility of this tendon can also be addressed with physiotherapy. Other issues that may be corrected may be weakness of the hip rotator muscles (core muscle strengthening), and assessing the alignment of the foot, which can place abnormal forces on the patella itself.

Medications


Anti-inflammatories (NSAIDs) like Nurofen are often used during painful periods to settle the early phases of the inflammation process. Starting on an anti-inflammatory can help make it easier for you to start your rehabilitation. These should only be taken for short courses as recommended by your surgeon.

Other Treatments for Anterior Knee Pain


Taping the patella is often used to help the patella glide with less pressure. Your physiotherapist may trial this to see if it helps in relieving your anterior knee pain. Occasionally patellar braces may be useful in supporting the knee. Orthotics are often useful for people with flat feet as arch supports may improve the overall biomechanics of the lower limb. Over the counter arch supports are often a reasonable and relatively inexpensive option to trial.

Surgery for Anterior Knee Pain


Surgery for anterior knee pain is considered a last resort after all other treatments have failed. If there is fraying (chondromalacia) or a loose flap of cartilage behind the patella or on the trochlear groove, a knee arthroscopy may help smooth out the affected area. Sometimes the ligaments on the outer aspect of the patella are tight, causing it to tilt producing excessive pressure on the outer aspect of the patellofemoral joint. Releasing the tissues (a lateral release) may help reduce the tilting of the patella and the pressure on this side, improving your pain. Very rarely a small part of the tibia bone (tibial tubercle) needs to be shifted so as to realign the way that the patella glides on the femur. This is called a tibial tubercle osteotomy. This is a larger operation and is used as a last resort in patients with severe pain not relieved by other modalities. The surgeons at SKS specialise in these procedures and we will discuss these options with you further if required.


Prevention for Anterior Knee Pain


Chronic persistent pain needs to be reported to the doctor immediately. Once the pain has been treated, a recurrence can be prevented by following a few simple measures which include:

  • Try not to suddenly change your exercise regime in a way that places unexpected strain on your knees; always introduce new elements gradually.
  • Wearing appropriate shoes for your sporting activities.
  • Performing warm up exercises before any physical activity.
  • Discontinue any activity causing pain in your knees.
  • Modulating the intensity of activity depending on your condition.
  • If you go running, attempt to stay on flatter roads and avoid an overload of running downhill.