Knee pain

ACL, MCL, & Meniscus - the big 3

In sports medicine these three types of knee injury are sometimes considered as ‘the big 3’. It’s particularly important to properly triage and correctly diagnose these injuries,to ensure the best chances of returning to sport and active daily life.

Patellafemoral pain syndrome (PFPS)

Patellofemoral Pain Syndrome (PFPS), commonly known as runner’s knee, is a condition that causes pain around or behind the patella (kneecap), particularly during activities like running, squatting, kneeling, or climbing stairs. It's a prevalent cause of knee pain, especially among athletes, active individuals, and those who engage in repetitive knee movements. While it affects people of all ages, it is most common in teenagers and young adults, especially females.

PFPS symptoms:

  • The pain is often located around the front of the knee or beneath the knee cap.

  • Aggravated by activities such as climbing stairs, squatting or kneeling.

  • The pain is often described as a dull ache and hard to pinpoint.

  • Small swelling or effusion of the knee.

  • Crepitus (Grinding or Popping Sensation).

  • Pain on Prolonged Sitting (Theatre Sign).

Patella tendinopathy

This condition characteristically presents as anterior knee pain with jumping, running, and other ballistic activities. Often with pain and stiffness after rest e.g. in the early morning, or walking after sitting. Patellar tendinopathy is common in jumping sports ("Jumper's knee") and jumping activities.

Common symptoms:

  • The most characteristic symptom is a dull ache or sharp pain at the front of the knee, just below the kneecap, where the patellar tendon attaches to the tibia, often worsened by activity, particularly those that involve jumping, squatting, running, or climbing stairs.

  • Pain During or After Activity:

  • Swelling and Tenderness

  • Stiffness in the knee, especially in the morning.

  • Weakness in the quadriceps muscles.

  • Decreased jumping ability and speed.

Fat pad impingement

The infrapatellar (Hoffa's) fat pad is a highly innervated and vascularised extra-articular structure located distal to the patella and directly beneath the patellar tendon. Oedema within the fat pad can trap the fat pad between the patella, tibial plateau and femoral condyles during deep knee flexion or end of range extension. This impingement causes a sudden sharp pain which lingers as a dull ache afterwards. Repetitive impingement is likely to exacerbate oedema and maintain the painful cycle.

Typical symptoms:

  • The pain is typically localised to the front of the knee, just below the patella. It may be described as a dull ache or sharp pain, and it can worsen with activities that involve knee flexion, such as squatting, jumping, running, or kneeling.

  • Pain with Prolonged Sitting (Theatre Sign).

  • Swelling or Tenderness.

  • Limited Range of Motion.

  • Pain with Kneeling.

  • Pain on Stairs or Inclines.

Pens anserine bursitis

The pes anserine region is located on the proximal anteromedial aspect of the tibia and is the common tendinous insertion of the sartorius, gracilis, and semitendinosis muscles. Anteromedial knee pain may be caused by tendinopathy of one of these three tendons. Pain from pes anserine tendinopathy and bursitis is usually of insidious onset. It is worse with exercise (especially running) or ascending stairs. Bursitis is common in older patients with osteoarthritis and less common among younger individuals.

Common symptoms:

  • The pain is typically felt just below the knee joint on the inner side of the tibia (shin). The discomfort may be sharp, aching, or burning in nature.

  • Pain Worsens with Activity involving knee flexion.

  • Tenderness to touch.

  • Stiffness and Decreased Range of Motion.

  • Worsening Pain after Prolonged Sitting (Theatre sign).

  • Pain after Physical Activity