Anterior Knee Pain

Patellofemoral Pain Syndrome (PFPS) is a lower limbs condition affecting people across all life span (Crossley, 2016). PFPS causes knee pain during flexion and extension, and it is felt during running, stair ascent, descent or when squatting. This syndrome is characterized by knee pain of varying degree. The pain originates from grinding of the femur with the posterior end of the knee patella (Crossley, 2016). This condition is common among athletes especially runners, basketball players and cyclist. It limits exercise and movement, especially in areas where one has to hold their knees. If left untreated for long, PFPS may lead to muscle dysfunction especially the thigh and triceps, tight lateral restraints, poor quadriceps flexibility, patellar hypermobility, overuse and even trauma (Dixit, DiFiore, Burton and Mines, 2008).This paper looks at all possible cause of anterior knee pain with an in-depth discussion of the epidemiology of PFPS, the causes, diagnosis and treatment. Other similar conditions that cause anterior knee pain also analysis and also all the possible tests used to diagnose this conditions.

Anterior knee pain may be due to different causes. Most of the knee pains may be caused by a physical injury such as falling, kneeling on a hard or cold surface for a long time or being hit. Physical knee injury may end with time depending on the level of injury. Anterior knee pains may be caused by preexisting conditions such as arthritis, plica syndrome, and synovial impingement or Patellofemoral Pain Syndrome (Ma, Zieve and Ogilvie, 2017). Anterior knee pain can be caused by softening of the posterior surface of the patella- a condition is known as chondromalacia. It can also be caused by lateral compression syndrome where the knee cap dislocates to the outside of the knee (Ma, Zieve and Ogilvie, 2017). According to Ma, Zieve and Ogilvie (2017) quadriceps tendinitis also causes anterior knee pain due to the tenderness of the quadriceps tendon at its attachment to the patella. All these conditions have similar symptom as well as treatment to the Patellofemoral Pain syndrome since they involve damage to the knee cap surface. Chondromalacia patellae syndrome is often confused with the PFPS due to the similarity of the affected area. The two conditions are, however, different because Chondromalacia patellae syndrome involves softening of the posterior surface of patella while PFPS refers to the damage. Diagnosis of PFPS is only made clinically to ascertain that it is not Chondromalacia patellae syndromes using the patellar grind test prove (Dixit, DiFiore, Burton and Mines, 2008). Most patients with a diagnosis of Patellofemoral Pain Syndrome may or may not have a damaged knee cap.

The patellar grind is the test used to detect the patellofemoral joint disorder as well as cancel out similar conditions. This test is also referred to as Clarke’s test. The patient is instructed to lie with their face upwards or sit with their legs stretched. The physician or the examiner places their hand on top the patient's knee with the thumb and the index finger on both ends of the patellar. The examiner applies pleasure, and the patient is instructed to contract their quadriceps muscles gradually. If the patient experiences pain at their patellofemoral joint, then this is a positive test for PFPS (Barrett, 2017). According to Barrett (2017), the Clarke test can be performed by gently pushing the patellar directly, and the patient is instructed to contract the Quadriceps muscles as the examiner pressures the patellar. If this test causes the patient to complain of pain or cannot maintain the contraction due to retro patellar pain, then the patient is diagnosed positively with Patellofemoral Pain Syndrome (Barrett, 2017). The Patellar grind test is majorly based on researched structural set up of the patellofemoral joint, and it has not been tested for its efficiency. In many instances, patients will experience pain once their patellar is under pressure even if they do not exhibit patellofemoral pain. Barrett (2017) notes that there are no standardized tests for testing PFPS most of the known test are either unreliable or are untested. This leaves the patellar grind test as the only preferable test for PFPS.

Positive Patellofemoral Pain syndrome is characterized by a dull excruciating pain that is usually felt behind, below or on the side of the patella (Ma, Zieve and Ogilvie, 2017). A PFPS patient may also experience a grinding feeling as they flex their knees. An X-ray test may be done to check the condition of the patellar as a complement to the patellar grind test. Patellofemoral Pain syndrome can be corrected using a variety of methods which are proven in many PFPS case (Rodriguez-Merchan, 2014). Exercise therapy is the ultimate and most preferred remedy of PFPS. Physical exercise involves muscle activity, reaction forces and joint movement to enhance joint flexibility. Physical exercise is also encouraged to reduce body weight which might be causing this condition. Other treatment methods for PFPS include medication such as non-steroidal anti-inflammatory drugs and glycosaminoglycan polysulfate, resting, icing, braces taping, arch support and surgery (Rodriguez-Merchan, 2014).

The Patellofemoral Pain syndrome is a common condition in all demographics and professions. This condition has similar symptoms as other conditions that affect the patellar and the knee joint. To differentiate the PFPS from other conditions that cause anterior knee pain, the patellar grind test is the preferred test. This test has not been tested for its efficiency in diagnosing PFPS hence it is required to use with the support of X-ray and medical imaging to be certain if the pain is caused by patellar surface destruction.

References

Barrett, B. (2017). Patellar Grind Test - Physiopedia, universal access to physiotherapy knowledge. Physio-pedia.com. Retrieved from http://www.physio- pedia.com/Patellar_Grind_Test

Crossley, K., Stefanik, J., Selfe, J., Collins, N., Davis, I., & Powers, C. et al. (2016). 2016 Patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester. Part 1: Terminology, definitions, clinical examination, natural history, patellofemoral osteoarthritis and patient-reported outcome measures. British Journal of Sports Medicine, 50(14), 839-843. http://dx.doi.org/10.1136/bjsports-2016-096384

Dixit, S., DiFiori J.,P., Burton, M., & Mines, B. (2008). Management of patellofemoral pain syndrome.- PubMed - NCBI. Ncbi.nlm.nih.gov. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/17263214

Ma, B., Zieve, D., & Ogilvie, I. (2017). Anterior knee pain: MedlinePlus Medical Encyclopedia. Medlineplus.gov. Retrieved from https://medlineplus.gov/ency/article/000452.htm Rodriguez-Merchan, E. (2014). Evidence Based Conservative Management of Patello-femoral Syndrome. PubMed Central (PMC). Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4151435/