1. Patellofemoral Pain Syndrome (Runner's Knee)
The knee is the single most common site of injury in recreational runners, accounting for approximately 25–30% of all RRIs. Patellofemoral pain syndrome (PFPS) presents as diffuse pain around and behind the kneecap, typically worsening with prolonged running, descending stairs, or sitting with knees bent for extended periods. It is particularly common in runners who increase mileage rapidly, have hip abductor weakness, or exhibit high hip adduction during the stance phase of gait.
2. Iliotibial Band Syndrome (ITBS)
ITBS is characterised by sharp or burning pain on the outer aspect of the knee, typically appearing after a predictable distance into a run (the 'pain distance'). It is caused by compression and friction of the iliotibial band at the lateral femoral epicondyle. ITBS is strongly associated with hip abductor weakness and is more prevalent in runners who increase mileage abruptly or run on cambered surfaces or banked tracks.
3. Medial Tibial Stress Syndrome (Shin Splints)
Shin splints affect the distal two-thirds of the tibial shaft, presenting as diffuse aching along the inside of the shin, typically during and after running. They arise from bone stress and periosteal irritation. Key risk factors include abrupt increases in volume, hard running surfaces, and running in worn-out footwear. It is important to distinguish medial tibial stress syndrome from tibial stress fracture, which presents with focal point tenderness on direct bone palpation and should be evaluated with imaging.
4. Achilles Tendinopathy
Achilles tendinopathy is one of the most common and persistent running injuries, affecting approximately 5% of recreational runners annually and up to 7.4% of those training for marathons. Mid-portion tendinopathy (located 2–6 cm above the insertion) presents with morning stiffness, local tendon thickening, and pain that may initially reduce with warm-up. It responds well to progressive tendon loading programs but is notoriously slow to resolve if managed passively.
5. Plantar Fasciitis
Plantar fasciitis is characterised by sharp heel pain, classically worst with the first steps in the morning and after periods of rest. It involves irritation of the plantar fascia at its calcaneal insertion. Risk factors include a sudden increase in volume, tight calf muscles, and a history of ankle dorsiflexion restriction. Most cases resolve with progressive calf and intrinsic foot muscle strengthening, combined with appropriate load management.
6. Bone Stress Injuries
Bone stress injuries, ranging from bone stress reactions to complete stress fractures, represent the most serious category of running overuse injury. Common sites include the tibia, metatarsals, navicular, and femoral neck. The navicular and femoral neck are high-risk locations that may require surgical intervention if diagnosis is delayed. All suspected BSIs require imaging (MRI is gold standard) and medical clearance before returning to running.
All overuse injuries share one common thread: they develop when cumulative load exceeds the tissue's capacity to adapt. Address the load, not just the symptom.
