Posterior tibial tendon insufficiency
The posterior tibial tendon functions as a dynamic support for the foot arch, flexes the ankle, inverts the hindfoot and supinates and adducts the forefoot during stance. Progressive loss of the medial foot arch, medial foot and ankle pain and weakness are signs of tendon insufficiency. In the early stages ankle-foot orthoses, temporary walking boot or custom insoles are helpful. Tendon transfers, hindfoot osteotomies and tendon debridement are indicated. In the late stages arthrodesis (fusion of bones) is the only beneficial treatment. 
Achilles tendonitis
This group includes tendonitis at the insertion onto the heel bone, Achilles tendon or bursitis behind the calcaneus and Haglund deformities.
Insertional tendonitis often occurs with a tight heel cord and is usually caused by repetitive trauma and inflammation in middle aged individuals. Posterior heel pain, swelling, burning and stiffness are common symptoms. Shoe wear can cause heel pain due to direct pressure. First line treatment includes physical therapy, heel sleeves or pads, small heel lifts, shoe wear modification and activity modification. Steroid injections should be avoided at all cost as they can result in tendon tears. If conservative treatment fails surgical treatment may include debridement, prominent bone resection and excision of the bursa.
Retrocalcaneal bursitis is an inflammation of the bursa between the Achilles tendon and posterior aspect of the calcaneus. Haglund deformities are enlargements of the posterosuperior part of the calcaneus. Pain anterior to the tendon, pain with dorsiflexion and bony prominence are physical signs. Activity modification, anti-inflammatories, shoe wear modification are the first line treatments. Physical therapy is not always helpful. Again avoid steroid injections at all cost. If conservative treatment fails removal of the bursa and resection of the bone prominence are good options.
Achilles tendonopathies are generally caused by overuse of an already degenerative tendon. There is a genetic predisposition for this condition. The tendon is thickened, the tendon sheath inflamed and there is pain with activity, difficulty in running are typical presentations. Nonoperative treatment is successful in 60-90% and involves physical therapy, eccentric training, iontophoresis, heel lifts and anti-inflammatories. Controversial treatment options are aprotinine injections, TNT patches and prolotherapy. With failure of conservative treatment surgical options include percutaneous longitudinal tenotomies, excisions of the degenerative tendon tissue and tendon transfers.
Plantar fasciitis
The plantar fascia is a thin layer of tissue that supports the arch of the foot.
Inflammation causes pain at the origin on the calcaneus. Overuse and repetitive trauma leads to microtears and inflammation with heel pain. It is worse when getting out of bed and at the end of the day with prolonged standing. Treatment includes pain control measures, stretching , foot orthoses, cushioned heel inserts and night splints. Cortisone injections are helpful but can lead to fat pad atrophy. Shock wave treatment is indicated if symptoms lasts longer than 6 months but outcome varies. Surgical release have a success rate of 70-90% but recovery can be protracted.
Sesamoid injuries of the hallux
Two small sesamoid bones are located within the flexor tendon of the big toe and assist with absorbing weight, reduce friction, protect the tendon and provide a fulcrum for the flexor tendon increasing flexion power. Forced dorsiflexion of the big toe, sudden acceleration and deceleration can result in fractures, dislocations, sprains, inflammation or tendonitis.Generalized big toe pain with weight-bearing or in the terminal phase of stance with toe off are the most common symptoms. Radiographs should always be performed to exclude fractures. Stiff soled shoes, reduced weight-bearing and activity modification are the mainstay of treatment. Surgery is indicated if non-operative treatment fails.