A calcaneal spur or heel spur is a bony outgrowth that mostly develops at the plantar surface of foot or at the back of heel. These spurs typically involve calaneus or os calcis, the largest and most weight bearing bone of tarsal bones of foot. These are often associated with pain due to inflammation of Ascilles tendon (Aschilles tendonitis) and plantar fascia (plantar fasciitis).
Calcaneal spurs can be a source of significant morbidity when associated with pain. Patient gradually develops pain over weeks and months. Pressure over medical aspect of heel may elicit tenderness. Spur in itself does not cause pain, but rather it is inflammation of surrounding structures that does.
Pain typically occurs at the back of heel or under the sole of foot. Heel pain is not an absolute feature. Many are asymptomatic at the time of discovery of a spur by radiographical examination. Plantar (inferior) spurs are more commonly related to heel pain, patients of plantar fasciitis either present or have a history of pain. But again, not all of the patients are symptomatic, even in this case. The chances of a person to have heel pain may be linked to following factors:
Most extend 2 to 2.5 cm beyond origin, some are large enough to be palpable and some are even visible to naked eye. Older people are more likely to develop larger spurs. Some may have both types of spurs, but majority of the patients present with only one type. Heel pain signifies plantar fasciitis or inflammation of structures surrounding the spur. Patient may complain of pain in heel after waking up in morning, with or without stiffening of foot and calf muscles. Pain may be of gradual onset in some, building up in intensity with activity or along the day; pain may be worsened by increased workload such as lifting heavy weight. Quality of pain varies; some describe it as sharp or stabbing in nature, others complain of dull and aching pain. Pain makes it difficult for patient to walk, run, or even stand in some advanced cases. The problem is aggravated by stiffness of muscles. Walking on hard surfaces also exacerbates the condition. Daily activities are impaired if condition is severe. Resting may relieve symptoms to some extent but pain recurs on getting up or resuming foot activity. Sometimes fractures occur, separating the spur from main bone. These fractures may occur spontaneously or after trauma. A wide majority of patients have no heel pain despite radiographic visualization of spurs. Occupational and environmental factors, level of physical activity and type of footwear may also modify symptoms in patients.
The mainstay for the diagnosis of calcaneal spurs is X-ray, which shows a bony spur extending infero-medially (typical of plantar spurs that are more frequently observed) from os calcis; a spur may also be seen posterior to heel bone. X-ray is taken in sagittal plain (lateral or lateral oblique view) in which spur can be easily appreciated, as an "exostoses". Most cases, however, can be clinically diagnosed before radiological examintion. A typical history of chronic foot pain worsens over time, and clinical examination of foot are helpful in reaching at a diagnosis; confirmation requires imaging techniques. Rarely MRI and ultrasound are also performed that reveal the extent of inflammation of surrounding tissues.
Regarding the causes of heel pain, other pathologies might be considered such as diabetes mellitus, trauma and degenerative diseases, autoimmune pathologies like Reiter's disease or crystal deposition disease or gout. X-ray also help rule out some of other similar pathologies such as rheumatoid arthritis.
Both medical and non-medical treatment strategies are employed in order to treat bony spurs. While medical therapy may provide an effective symptomatic treatment, non-medical therapies are even more useful as many of them involve mechanical or some other form of energy to destroy/reduce/remove calcaneal spurs.
Conventionally, both steroids and NSAIDS (Non steroidal Anti-inflammatory Drugs) are involved in treatment regimen of patients presenting with heal pain. Steroids are given in oral and injectible forms; they reduce inflammation. Non steroidal anti-inflammatory drugs are also used for the purposes of reducing pain and inflammation.
Physiotherapy is a mainstay of non-surgical treatment of spurs. Patients are advised to do both active and passive stretching of legs, and other orthopedic exercises. Life-style modifications are also required for better outcome in patients. Walking on hard surfaces, excessive pronation, lifting heavy weight (while walking) and too much walking are to be avoided. Ill-fitting and uncomfortable shoes must not be worn by patients as they can aggravate pain. Offloading is done in order to avoid too much pressure being transmitted to foot while standing or walking (os calcis serves as weight bearing structure of foot in both cases). Both partial and complete offloading is performed. Doctors also prescribe orthotic devices such as:
Contrast bath means alternative application of cold and warm water to limb with the aim to reduce inflammation. This therapy is also known as heat/cold immersion therapy. The procedure is repeated several times for the whole of limb or a part of it.
Conventional therapy may take six to twelve months, and hence, patients inevitably suffer from a chronic problem.
Ultrasound, LASER and cryotherapy treatment are also very effective. ESWT (Extra-corporeal Shockwave Therapy) is a procedure in which high energy mechanical waves are directed at calcaneal spur. These waves are thought to increase growth of blood vessels and reduce inflammation. Both conventional method and ESWT are believed to be same, but ESWT is considered less effective for plantar fasciitis  .
Surgery is necessary only in refractive cases. Posterior calcaneal spurs are removed as a part of treatment of insertional Aschilles tendinitis. Partial plantar fasciotomy procedure has been supported by evidence of good long-term prognosis in patients who have undergone it.
Calcaneal spurs and plantar fasciitis take long time to subside without appropriate treatment. Minor damage takes mere weeks or few months but larger spurs may cause chronic morbidity unless treated by aggressive measures. Early preventive measures to eliminate predisposing factors, or reducing the aggravating factors, also improves prognosis in patients.
Calcaneal spurs can cause considerable morbidity especially in athletes and sportsperson. Planter fasciitis, with or without heal spurs, may last more than 12 months or longer before it subsides. Prevention against progression and complications can significantly improve chances of good prognosis, although calcaneal spurs, once developed, are difficult to treat without surgical and other aggressive interventions.
Although etiology of calcaneal spurs has long been debated, present view supports a mechanical basis for this abnormal growth. With constant mechanical stress, calcium deposits form in heel. Excessive pronation has been proposed to be the cause of formation of plantar calcaneal spurs (in accordance with longitudinal traction hypothesis, as explained later). Similarly obesity and degenerative changes associated with aging are also shown to be related to spur formation. "Vertical compression hypothesis" explains association of obesity and senililty associated degenerative changes with spur formation stating that vertical heel pressure during gait is directly correlated with body weight. Accelerated degenerative changes occur in tendon in people with obesity and increased body weight. Stiffening of muscles tends to aid in the process. Another hypothesis states that increased weight tends to flatten the medial longitudinal arch, adding to traction on ligaments and resulting in formation of bony spurs. Osteoarthritis is also thought to contribute towards spur formation by similar mechanism. With osteoathritis, processes like subchondral sclerosis and degenerative changes of fibrocartilage accelerate processes that have been experimentally proven to be linked to calcaneal spurs. A "direct association" has been found by epidemiological studies between osteophytes (feature of osteoarthritis) and spur formation. This proves that age related degenerative changes of skeletal system (including osteoarthritis) are somehow related to these bony growths.
Apart form abnormal bio-mechanics, other associated factors include Niesseria Gonorrhoea, Tuberculosis, metabolic disorders, heredity and systemic inflammation (some of these are experimentally unproved). Women who wear high heels are more prone to develop calcaneal spurs. Moreover, athletes are also more likely to develop these spurs as compared to normal individuals.
Calcaneal spurs are most often found as incidental findings alongwith painful plantar heel , which most commonly, arises from plantar fasciitis in the medial aspect of proximal attachment of plantar aponeurosis (although any component of aponeurosis may be the source of focal tenderness). The tender area corresponds to calcaneal spur, that is very often found concurrently in radiographic studies. Hence, significant number of patients visiting OPD (Outdoor Patient Department) with heel pain are diagnosed as having traction enthesopathy (disorders involving tendon or ligament of bone and arising from traction).
Studies have shown greater prevalence in older age group. Older people also tend to have larger calcaneal spurs. Out of 38% of the whole population that presented with spurs, about 11% had both types while the rest showed unilateral problem. Women (especially those who wear high heels) have significantly higher rate of development of these spurs and a positive correlation has been found between the two types of spurs in women less than thirty years of age. This correlation was absent in men. Moreover, radiographic appearance of spurs also differs between men and women. Studies have also shown that these spurs appear more frequently in obese people (45% of participants of a study had problem as compared to 11% of people who were not obese), flat footed people and athletes. Obesity has been found to have a direct and strong association. Pressure, traction and inflammation are thought to be likely risk factors for spur development. Barrett reported that 21% of cadaveric feet possessed heal spur  and Rubin found that 10% of cases presented with symptomatic problem (out of 21% population with heel spurs) . Shama et al. reported a higher number of symptomatic patients . Out of 1000 patients, 132 were found symptomatic in this study, still these patients formed less than half of their whole study population. On the other hand, many patients with heel pain were actually patients of plantar fasciitis and lacked any significant association with heel spurs. A study conducted on patients of plantar fasciitis found that 63% patients of plantar fasciitis in their study population had no heel spurs .
Conventional therapy can resolve heel pain in 90% of patients with or without spur reduction.
Calcaneal spurs are of two types:
Dorsal or posterior spurs: these are often large and develop at the insertion of Aschilles tendon, at the posterior part of calcaneus. These are sometimes visible to naked eye and are readily palpable. They may cause pain with inflammation of Achilles tendon.
Plantar or inferior spurs:
These spurs develop on the inferior aspect of sole and may occur in response to plantar fasciitis or be related to ankylosing spondylitis (in children). Plantar calcaneal spurs are thought to result from enthesophytic changes involving the insertion of the plantar aponeurosis.
The exact pathophysiology of calcaneal spurs is yet to be understood . Numerous hypotheses have been proposed including vertical compression hypothesis, longitudinal traction hypothesis and others, but exact cause still remains unknown.
Vertical Compression Hypothesis: it states that vertical compression during gait is associated with spur formation. The greater the pressure (as in obese people), the greater will be chances of spur formation.
Longitudinal Traction Hypothesis: it states that traction along the length of plantar aponeurosis is associated with spur formation. All these views explain that either constant pressure, compression, traction or a combination of these may be the reason of spur formation. Although flat footed people have not been found to have spurs as demonstrated by various radiographical examinations performed by Menz et al , as well as by lack of sufficient biological plausibility, scientists have therefore hypothesized that spur formation may more possibly be related to compression than traction. Plantar fascia in flat footed people is more prone to traction enthesopathy. Heel pain is, therefore, commonly found in these patients that may or may not be associated with calcaneal spurs.
Although there are no specific preventive measure for this condition, incidence can be reduced by life-style modifications.
Following are some of these measures:
Calcaneal spurs/ heel spurs or enthesophytes were first documented in 1900. German physician Plettner called them kalkaneussporn. Calcaneus bone is an important component of plantar skeleton providing support, acting as a lever for calf muscles, and a weight bearing structure while standing or walking. It is the longest and strongest of all tarsal bones and forms bony prominence of heel. It has a tuberosity, a rough surface providing attachment to Aschilles tendon, and medial and lateral surfaces that extend on either side from main body of bone, separated by a notch. Enthesophytes (heel spurs) typically develop along attachment of tendon and ligaments on calcaneus, and grow along the line of pull of tendon. With constant stress, calcium deposits form in calcaneus that do not cause any problem as long as minute. However, it time these deposits pile up over each other, forming a larger, irregular shaped deformity, called a calcaneal (or heel) spur. This larger calcaneal deformity may cause pain by impinging on surrounding structures. Spurs are 2 to 2.5 cm in size, grow into plantar fascia (causing plantar fasciitis) lying anteriorly to heel bone, or in Aschilles tendon causing Aschilles tendinitis.
It is a chronic condition and lasts for many months before subsiding. Women (especially those who wear high heels regularly) and obese people frequently present with this problem.
Calcanues is the largest and strongest of tarsal bones, serving as a posterior pillar for medial and lateral longitudinal arches. Calcaneal spurs are abnormal bony outgrowths that appear on inferior or posterior part of calcaneus. The exact pathophysiology and etiology of spur formation is unknown. However, that abnormal traction, compression or pressure have been proposed to contribute to its development. Many factors can cause these aberrant bio-mechanics including obesity, osteoarthritis, ill fitting foot wear, degenerative disease of cartilage, ligaments and bones. Incidence is higher in women as compared to men of same age, older people, women who wear high heels and athletes.
The condition is chronic and mainly manifests as heel pain over the posterior or inferior aspect of heel, depending upon site of spur. Pain results from the inflammation of the surrounding soft tissue. Fractures may also occur in a spur, aggravating the pain. Treatment can consist both in a symptomatic approach and the removal of spur. Preventive measures, such as well-fitting shoes, reduction of weight, and avoidance of aggravating factors contribute to good prognosis.