A 2013 review found the incidence of tendon injury among those taking fluoroquinolones to be between 0.08 and 0.2%. Fluoroquinolones most frequently affect large load-bearing tendons in the lower limb, especially the Achilles tendon which ruptures in approximately 30 to 40% of cases. Types
Achilles tendinitis
Calcific tendinitis
Patellar tendinitis (jumpers knee)

Pathophysiology
As of 2016 the pathophysiology of tendinopathy is poorly understood. While inflammation appears to play a role, the relationships among changes to the structure of tissue, the function of tendons, and pain are not understood and there are several competing models, none of which have been fully validated or falsified. Molecular mechanisms involved in inflammation includes release of inflammatory cytokines like IL-1β which reduces the expression of type I collagen mRNA in human tenocytes and causes extracellular matrix degradation in the tendon.There are multifactorial theories that could include: tensile overload, tenocyte related collagen synthesis disruption, load-induced ischemia, neural sprouting, thermal damage, and adaptive compressive responses. The intratendinous sliding motion of fascicles and shear force at interfaces of fascicles could be an important mechanical factor for the development of tendinopathy and predispose tendons to rupture.The most commonly accepted cause for this condition is seen to be an overuse syndrome in combination with intrinsic and extrinsic factors leading to what may be seen as a progressive interference or the failing of the innate healing response.
Diagnosis
Symptoms can vary from aches or pains and local joint stiffness, to a burning that surrounds the whole joint around the inflamed tendon. In some cases, swelling occurs along with heat and redness, and there may be visible knots surrounding the joint. With this condition, the pain is usually worse during and after activity, and the tendon and joint area can become stiff the following day as muscles tighten from the movement of the tendon. Many patients report stressful situations in their life in correlation with the beginnings of pain which may contribute to the symptoms. Medical imaging
Ultrasound imaging can be used to evaluate tissue strain, as well as  other mechanical properties. Ultrasound-based techniques are becoming more popular because of its affordability, safety, and speed. Ultrasound can be used for imaging tissues, and the sound waves can also provide information about the mechanical state of the tissue. Treatment
Treatment of tendon injuries is largely conservative. Use of non-steroidal anti-inflammatory drugs (NSAIDs), rest, and gradual return to exercise is a common therapy. Resting assists in the prevention of further damage to the tendon. Ice, compression and elevation are also frequently recommended. Physical therapy, occupational therapy, orthotics or braces may also be useful. Initial recovery is typically within 2 to 3 days and full recovery is within 3 to 6 months. Tendinosis occurs as the acute phase of healing has ended (6–8 weeks) but has left the area insufficiently healed.