Definition/Description
Heel spur
Calcaneal spurs, or commonly known as calcaneal spurs, occur when bony growths form on the heel bone. Calcaneal spurs can be located on the back of the heel (heel spur) or on the bottom of the foot (plantar heel spur). Bone spurs on the dorsal side are often associated with Achilles tendinopathy, while the bone spurs are on the lower the heel is associated with Plantar fasciitis.
The apex of the spur lies within the origin of the plantar fascia (on the medial tubercle of the calcaneus) or above the origin of the plantar fascia (on the origin of the flexor digitorum brevis). The relationship between the formation of the medial tubercle of the calcaneus and the inner musculature of the heel This results in a constant stretching effect on the plantar fascia, leading to an inflammatory response. [1]
Clinically Relevant Anatomy
Intrinsic foot muscles
There are many muscles (Soleus gastrocnemius plantaris abductor digiti minimi flexor digitorum flexor extensor digitorum brevis abductor hallucis extensor hallucis brevis brevis plantae) and the plantar fascia exert traction on the tuberosity and adjacent areas Calcaneus especially when excessive or abnormal pronation occurs. The origin of the bone spur appears to be caused by repetitive trauma that creates a tiny tear in the plantar fascia near its attachment point, and attempts to repair it can lead to the inflammation that causes the spur to develop and Maintain symptoms. [2][3][4][5]
Epidemiology /Etiology
The cause of bone spurs has been debated. Inherited metabolic disorders, tuberculosis, systemic inflammatory diseases, and many others have also been implicated. Current reasoning is that abnormal biomechanics (excessive or abnormal pronation) are the primary cause of plantar pain Heel and inferior calcaneal spurs. Bone spurs are thought to be the result of a biomechanical malfunction and are an incidental finding associated with plantar heel pain. The most common cause is thought to be abnormal pronation, which results in increased tension within the structure Attaches to the area of the calcaneal tuberosity.
Asymptomatic heel spurs are relatively common in the normal adult population. An epidemiological study found that 11% of the U.S. adult population developed calcaneal spurs, which appear on incidental radiological findings. [6]
Image: Overview of the calcaneus bone[7]
Characteristics/Clinical Presentation
Heel pain is a relatively common foot problem, but heel spurs are not a major cause of heel pain. Calcaneal spurs are caused by long-term stress on the plantar fascia and muscles of the foot, and may be a reaction to plantar fasciitis. [8]
The pain is mainly concentrated in the area of the medial process of the calcaneal tubercle and is caused by pressure on the area of the plantar aponeurosis that attaches to the calcaneus. This condition may exist without producing symptoms, or it may become very painful and even disabling. [9]
Most people with heel pain are middle-aged. Obesity may be considered a risk factor. Not all heel spurs cause symptoms and are usually painless, but when they do, people usually feel more pain in the morning with weight-bearing activities or after a period of rest. pain However, this is not the result of mechanical stress on the bone spur, but rather an inflammatory response.
Type of calcaneal spur
There are 2 types of calcaneal spurs;
- Type A spurs are better than plantar fascia insertions
- Type B spurs extend anteriorly within the plantar fascia from the insertion point of the plantar fascia.
The mean spur length of type A spurs was statistically significantly longer than that of type B spurs, although patients with type B spurs reported more severe clinical pain. [10]
Spurs can be divided into three different types:
- Some were larger but asymptomatic because the growth angle allowed bone spurs and/or inflammatory changes that had been aggravated by weight bearing to have stopped. [11]
- The second type is larger but painful when bearing weight, because the inclination of the calcaneus has been changed by the depression of the longitudinal arch, and as a result the bone spur may become the weight-bearing point, sometimes causing intractable intractable pain. [11]
- This third type has only a small amount of hyperplasia with an irregular and jagged outline, often with an area of decreased density around the origin of the plantar fascia, indicative of a subacute inflammatory process. All calcaneal spurs undoubtedly begin this way, but only a few Symptoms appear at this stage because the etiology is acute. [11]
Differential Diagnosis
Because chronic heel pain is a common manifestation of many conditions, these conditions must be ruled out before planning treatment. Diagnostic imaging and medical signs are often used to differentiate some of the conditions mentioned below from a calcaneal spur.
Musculoskeletal Causes
- Peroneal tendonitis: (inflammation of one or both peroneal tendons)
- MRI scan or ultrasound investigation
- Haglund’s deformity (with or without bursitis): symptomatic bony posterosuperior protrusion of the calcaneus
- X-ray or ultrasonography of maximally dorsiflexed foot [12]
- Sever’s disease (calcaneous apophysis): inflammation of the calcaneal apophysis due to overload
- Clinical [13] Ultrasound examination [14]
Traumatic Influences
- Calcaneal fractures (and stress fractures): fractures that result from repetitive loading of the heel
- Ottawa ankle regular radiography MRI (isotopic bone scan) and ultrasound. [15]
Neurological Causes
- Baxter’s nerve entrapment: (chronic compression of the first branch of the lateral plantar nerve)
- Clinical (Tinel’s sign)
- Tarsal tunnel syndrome (sinus tarsi): posterior tibial nerve involvement
- Clinical (Tinel sign dorsiflexion-valgus test)
Other
- Heel fat pad syndrome: atrophy or inflammation of the shock-absorbing fat pad or fat body
- Clinical, ultrasound scan
- Chronic lateral ankle pain from other causes:
- MRI
Diagnostic Procedures
Diagnosis is based on the patient’s medical history and physical examination findings. Diagnosis is usually confirmed by X-rays, but other diagnostic aids are also used. [16] Radiology may show calcaneal spur formation or calcification at the Achilles tendon insertion or Origin of the plantar fascia. [17] MRI is rarely required.
Outcome Measures
- Lower Extremity Functional Scale (LEFS)
- Outcome Measures Database
Examination
There are different aspects to consider when conducting a clinical examination.
- Is the range of motion of the ankle and foot limited, especially passive dorsiflexion of the toes?
- Palpation of the proximal plantar fascia attachment on the heel. If there is a calcaneal triggering any fracture (location/severity) or any deformity (including the dorsiflexion) .
- Is the heel pad atrophied with decreased muscle strength compared to the other foot?
- Is there any swelling?
- Sensation
- Is there tibial nerve hypoesthesia/dysesthesia? Tynell’s sign
- Are there any skin tears on the foot?
- Is there any difference in the alignment of the foot compared to the other foot?
- Aggravation on weight-bearing?
- Evaluation of gait
Management
The 2010 revision of the Clinical Practice Guidelines outlines the different stages by tier. If symptoms are relieved to a certain level, treatment should be continued. If no improvement is reported, treatment will be moved to a higher level.
Recommended treatment schedule before escalation if symptoms do not improve: Tier 1: 6 weeks Tier 2: 6 months Tier 3: 6 months
Medical Management
Grade I ● Nonsteroidal anti-inflammatory drugs (NSAIDs) [18] Grade I recommendation ● Cortisone injection [19] Grade B recommendation
Tier II ● Repeat cortisone injections[20][21][22] Grade B recommendation ● Botulinum toxin[23][24][25] Grade I recommendation
Tier III ● Endoscopic plantar fasciotomy [26] ● Stepped fasciotomy [27][28] ● Minimally invasive surgical technique All grade B recommendations
Conservative Management
Layer 1 ● Foot pads and straps [29][30]
● Therapeutic orthotic insoles for short-term pain relief[31][32] ● Achilles tendon and plantar fascia stretching[33][34] ● Prefabricated and custom orthotics. Prefabricated devices have been shown to be more effective in improving symptoms compared to custom-made devices [35] Grade B recommendation Night splints [36] Grade B recommendation Physiotherapy [37] Grade I recommendation Cast or boot immobilization [38] Grade C recommendation
Tier III ● ESWT (extracorporeal shock wave therapy) [39][40][41][42] Grade B recommendation ● Bipolar radiofrequency (microtenotomy) [43] Grade C recommendation
Missing Evidence in the Guidelines
Some treatments have been shown to be effective in treating plantar fasciitis, but not in the presence of a heel spur. Therefore, these recommendations should only be used when the heel spur is associated with plantar fasciitis.
Bipolar radiofrequency (microtenotomy): In the guidelines, this treatment received a grade C recommendation. This rating may change in the future, pending new research.
- March 2015: “Bipolar radiofrequency microtenotomy appears to be a safe procedure that provides comparable results to open surgery and a lower incidence of refractory plantar fasciitis.” [44]
- December 2015: “RM is as effective as PF in treating plantar fasciitis. Patients undergoing either procedure experience no benefit and higher complication rates.” [45] For long-term efficacy, a larger research cohort.
Physical Therapy Management
Both the upper and lower calcaneal spurs were treated with conventional physical therapy.
- Low-dose radiation therapy (radiation side effects and syndromes)
Using this approach, there is evidence that restimulation of painful heel spurs is a safe and effective treatment. Significant response in pain reduction for at least 2 years, although a placebo effect may be present [47] . However, there is no definitive decision on what dosage 1.0 Gy or 0.5 Gy are most effective. - Cryosonography and cryotherapy are both effective in treating chronic plantar fasciitis with heel spurs. Cryosound therapy seems to provide better results. [48]
- Thermotherapy
Cold therapy can be used to reduce inflammation and reduce pain.
Heat therapy can relax tense muscles and boost oxygen and blood flow to affected areas. [49] Heat therapy may help reduce pain during exercise. - Low-level laser therapy has been found to be an effective treatment for heel spurs. Although more studies with larger groups are needed for more evidence. [50]
- Conventional therapy includes ultrasound laser therapy with passive and active stretching and the application of heat and cold (contrast baths) to strengthen the leg muscles. The goal is to eliminate the inflammation around the bone spur. Symptoms may take 6 to 12 months on this treatment regimen resolution.
- Conservative treatment: While conservative treatment can help reduce the symptoms of a bone spur, it doesn’t always treat the source of the pain.
- Radial Shockwave Therapy consists of extremely high-energy mechanical waves targeting plantar fasciitis to help reduce inflammation.
- Extracorporeal Shockwave Therapy (ESWT): Various studies have indeed shown that ESWT is not an effective treatment for plantar fasciitis. (Buchanan et al. 2002 Haake et al. 2003) This discrepancy between studies implies that further support for effective treatment of ESWT is needed, as there are ESWT had a significant positive effect on calcaneal spurs, but the difference between the presence and absence of calcaneal spurs was not significant enough. [51] According to De Vera Barredo et al. (2007), nighttime splints, massage, taping, acupuncture, walking plaster, laser therapy, and cryotherapy are more effective. Shafshak reported that ESWT appeared to be effective in relieving heel pain in patients with calcaneal spurs, especially when given within the first 4 months after patients developed symptoms. ECSWT is recommended as the first choice for the treatment of calcaneal spurs and is the most Effective when healing for at least 3×500 pulses. [52] However, Yalcin suggested that ESWT may not be the most effective treatment for heel spurs. After five sessions of ESWT, no patients had significant reductions in bone spurs, but 19 patients (17.6%) had reductions in bone spur angles 23 patients (21.3%) had bone spur size reduction and one patient had a bone spur fracture. However, the therapy did have a dramatic effect in reducing the patient’s symptoms. Further research into the effectiveness of the ESWT is needed. [53]
Orthotics
The role of orthotics is only relevant if the heel spur is associated with plantar fasciitis.
Night Splints
night splints
Conservative treatment combined with night splints to maintain ankle dorsiflexion at 5 degrees for 8 weeks; patients with previously untreated plantar fasciitis experienced significant short-term relief of heel pain with night splints incorporated into the soles of the feet Conservative approach; however, this application was not significantly effective in preventing relapse after two years of follow-up.
Heel Inserts
Heel Inserts Heel inserts or heel spur pads are supposed to reduce heel spur pressure and inflammation, and reduce pressure by trapping impact and distributing it evenly across the entire heel. However, Chia stated that the heel spur pads were ineffective in reducing rearfoot pressure and increasing rearfoot peak forces, while orthotics and custom orthotics reduce rearfoot peak forces on both sides. Therefore, prefabricated and custom orthotics help distribute pressure evenly in the rearfoot area. [54]
Footwear Modification
Footlogics: Relieves plantar fasciitis (heel pain and heel spurs), Achilles tendinopathy and forefoot pain. Designed to correct over-pronated arches and flat feet. Insoles: Patients with heel pain diagnosed with a Sever injury wore insoles, no other treatment added, all Patients maintained a high level of physical activity throughout the study period. The use of insoles was found to significantly reduce pain during physical activity. [55]
Clinical Bottom Line
Calcaneal spurs are bony growths on the heel (dorsum) or bottom of the foot (plantar). Back bone spurs are associated with Achilles tendinopathy and plantar spurs are associated with plantar fasciitis. Their etiology appears to be related to repetitive trauma to the associated muscles and tendons Attempts to repair micro-tears that cause inflammation and pain. Abnormal biomechanics are thought to be responsible for this response. Pain in the heel is often felt, interfering with gait and weight bearing, but the differential diagnosis must be ruled out where possible Appropriate treatment options. X-rays are an effective diagnostic tool. Management can be medical or non-medical, depending on the individual’s response.
References
- ↑ Johal KS .,‘Plantar fasciitis and the calcaneal spur: Fact or fiction?’., Foot Ankle Surg.,18 March 2012 (level of evidence 3B)
- ↑ Gill LH. Plantar fasciitis: diagnosis and conservative management. J Am Acad Orthop Surg, 1997
- ↑ McCarthy DJ, Gorecki GE: The anatomical basis of inferior calcaneal lesions. J Am Podiatry Assoc 69527-536,1979 (level of evidence: 2C)
- ↑ Young CC, Rutherford DS, Niedfeldt MW. Treatment of plantar fasciitis. AmfckLRFam Physician 2001 (level of evidence: 5)
- ↑ Heyd, Reinhard, et al. “Radiation therapy for painful heel spurs.” Strahlentherapie und Onkologie 183.1 (2007): 3-9. (level of evidence: 1B)
- ↑ McCarthy DJ, Gorecki GE: The anatomical basis of inferior calcaneal lesions. J Am Podiatry Assoc 69527-536,1979 (level of evidence: 2C)
- ↑ Overview of the calcaneus bone image – © Kenhub [https://www.kenhub.com/en/library/anatomy/calcaneus
- ↑ E.K. Agyekum., “Heel pain: A systematic review”., Chinese Journal of Traumatology., 2015 (level of evidence 1A)
- ↑ B. Jasiak-Tyrkalska., ‘Efficacy of two different physiotherapeutic preocedures in comprehensive therapy of plantar calcaneal spur’., Fizjoterapia Polska., January 2007 (level of evidence: 1B)
- ↑ Zhou, Binghua, et al. “Classification of Calcaneal Spurs and Their Relationship With Plantar Fasciitis.” The Journal of Foot and Ankle Surgery 54.4 (2015): 594-600. (level of evidence: 3A)
- ↑ Jump up to:11.0 11.1 11.2 Henri L. Duvries., “Heel Spur (Calcaneal Spur)”., AMA Arch Surg., (level of evidence: 3A)
- ↑ Chauveaux, D., et al. “A new radiologic measurement for the diagnosis of Haglund’s deformity.” Surgical and Radiologic Anatomy 13.1 (1991): 39-44. (level of evidence: I)
- ↑ Perhamre, Stefan, et al. “Sever’s injury: a clinical diagnosis.” Journal of the American Podiatric Medical Association 103.5 (2013): 361-368. (level of evidence: 3A)
- ↑ Hosgoren, B., A. Koktener, and Gülçin Dilmen. “Ultrasonography of the calcaneus in Sever’s disease.” Indian pediatrics 42.8 (2005): 801. (level of evidence: 4)
- ↑ Yu, Sarah M., and Joseph S. Yu. “Calcaneal avulsion fractures: an often forgotten diagnosis.” American Journal of Roentgenology 205.5 (2015): 1061-1067. (level of evidence: 2A)
- ↑ Rosenbaum, Andrew J., John A. DiPreta, and David Misener. “Plantar heel pain.” Medical Clinics of North America 98.2 (2014): 339-352. (level of evidence: 2A)
- ↑ Aldridge, Tracy. “Diagnosing heel pain in adults.” American family physician 70 (2004): 332-342. (Level of evidence: 2A)
- ↑ Donley BG, Moore T, Sferra J, Gozdanovic J, Smith R. The efficacy of oral nonsteroidal anti-inflammatory medication (NSAID) in the treatment of plantar fasciitis: a randomized, prospective, placebo-controlled study. Foot Ankle Int 28:20–23, 2007.(level of evidence: 1B)
- ↑ Kalaci A, Cakici H, Hapa O, Yanat AN, Dogramaci Y, Sevinç TT. Treatment of plantar fasciitis using four different local injection modalities: a randomized prospective clinical trial. J Am Podiatr Med Assoc 99:108–113, 2009.(level of evidence: 1B)
- ↑ Kiter E, Celikbas E, Akkaya S, Demirkan F, Kilic BA. Comparison of injection modalities in the treatment of plantar heel pain: a randomized controlled trial. J Am Podiatr Med Assoc 96:293–296, 2006. (level of evidence: 1B)
- ↑ Buccilli TA Jr, Hall HR, Solmen JD. Sterile abscess formation following a cortico- steroid injection for the treatment of plantar fasciitis. J Foot Ankle Surg 44:466– 468, 2005. (level of evidence: 3A)
- ↑ Porter MD, Shadbolt B. Intralesional corticosteroid injection versus extracorporeal shock wave therapy for plantar fasciopathy. Clin J Sport Med 15:119–124, 2005. (level of evidence: 1B)
- ↑ Placzek R, Holscher A, Deuretzbacher G, Meiss L, Perka C. [Treatment of chronic plantar fasciitis with botulinum toxin Adan open pilot study on 25 patients with a 14-week-follow-up.]. Z Orthop Ihre Grenzgeb 144:405–409, 2006. German. (level of evidence: 1B)
- ↑ Placzek R, Deuretzbacher G, Meiss AL. Treatment of chronic plantar fasciitis with Botulinum toxin A: preliminary clinical results. Clin J Pain 22:190–192, 2006. (level of evidence: 1B)
- ↑ Babcock MS, Foster L, Pasquina P, Jabbari B. Treatment of pain attributed to plantar fasciitis with botulinum toxin a: a short-term, randomized, placebo- controlled, double-blind study. Am J Phys Med Rehabil 84:649–654, 2005. (level of evidence: 1B)
- ↑ Urovitz EP, Birk-Urovitz A, Birk-Urovitz E. Endoscopic plantar fasciotomy in the treatment of chronic heel pain. Can J Surg 51:281–283, 2008. (level of evidence: 2A)
- ↑ Fishco WD, Goecker RM, Schwartz RI. The instep plantar fasciotomy for chronic plantar fasciitis. A retrospective review. J Am Podiatr Med Assoc 90:66–69, 2000.(level of evidence: 2B)
- ↑ Woelffer KE, Figura MA, Sandberg NS, Snyder NS. Five-year follow-up results of instep plantar fasciotomy for chronic heel pain. J Foot Ankle Surg 39:218–223, 2000. (level of evidence: 2B)
- ↑ Shikoff MD, Figura MA, Postar SE. A retrospective study of 195 patients with heel pain. J Am Podiatr Med Assoc 76:71–75, 1986. (level of evidence: 2B)
- ↑ Williams PL. The painful heel. Br J Hosp Med 38:562–563, 1987. (level of evidence: 4)
- ↑ Landorf KB, Keenan AM, Herbert RD. Effectiveness of foot orthoses to treat plantar fasciitis: a randomized trial. Arch Intern Med 166:1305–1310, 2006.(level of evidence: 1B)
- ↑ Roos E, Engstrom M, Soderberg B. Foot orthoses for the treatment of plantar fasciitis. Foot Ankle Int 27:606–611, 2006.(level of evidence: 1B)
- ↑ DiGiovanni BF, Nawoczenski DA, Lintal ME, Moore EA, Murray JC, Wilding GE, Baumhauer JF. Tissue-specific plantar fascia-stretching exercise enhances outcomes in patients with chronic heel pain. A prospective, randomized study. J Bone Joint Surg Am 85-A:1270–1277, 2003.(level of evidence: 1B)
- ↑ Digiovanni BF, Nawoczenski DA, Malay DP, Graci PA, Williams TT, Wilding GE, Baumhauer JF. Plantar fascia-specific stretching exercise improves outcomes in patients with chronic plantar fasciitis. A prospective clinical trial with two-year follow-up. J Bone Joint Surg Am 88:1775–1781, 2006.(level of evidence: 2B)
- ↑ Pfeffer, Glenn, et al. “Comparison of custom and prefabricated orthoses in the initial treatment of proximal plantar fasciitis.” Foot & Ankle International 20.4 (1999): 214-221.(level of evidence: 1B)
- ↑ Lee, Sae Yong, Patrick McKeon, and Jay Hertel. “Does the use of orthoses improve self-reported pain and function measures in patients with plantar fasciitis? A meta-analysis.” Physical Therapy in Sport 10.1 (2009): 12-18.(level of evidence: 1A)
- ↑ Cleland JA, Abbott JH, Kidd MO, Stockwell S, Cheney S, Gerrard DF, Flynn TW. Manual physical therapy and exercise versus electrophysical agents and exercise in the management of plantar heel pain: a multicenter randomized clinical trial.(level of evidence: 1B)
- ↑ Cole C, Seto C, Gazewood J. Plantar fasciitis: evidence-based review of diagnosis and therapy. Am Fam Physician 72:2237–2242, 2005. (level of evidence: 1A)
- ↑ Lee, Gregory P., John A. Ogden, and G. Lee Cross. “Effect of extracorporeal shock waves on calcaneal bone spurs.” Foot & ankle international 24.12 (2003): 927-930. (level of evidence: 1A)
- ↑ Marks W, Jackiewicz A, Witkowski Z, Kot J, Deja W, Lasek J. Extracorporeal shock- wave therapy (ESWT) with a new-generation pneumatic device in the treatment of heel pain. A double blind randomised controlled trial. Acta Orthop Belg 74:98– 101, 2008. (level of evidence: 1B)
- ↑ Chuckpaiwong B, Berkson EM, Theodore GH. Extracorporeal shock wave for chronic proximal plantar fasciitis: 225 patients with results and outcome predictors. J Foot Ankle Surg 48:148–155, 2009. (level of evidence: 2B)
- ↑ Pribut SM. Current approaches to the management of plantar heel pain syndrome, including the role of injectable corticosteroids. J Am Podiatr Med Assoc 97:68–74, 2007. (Level of Evidence: 5)
- ↑ Weil L Jr, Glover JP, Sr Weil LS. A new minimally invasive technique for treating plantar fasciosis using bipolar radiofrequency: a prospective analysis. Foot Ankle Spec 1:13–18, 2008. (Level of Evidence: 4)
- ↑ Lucas, Douglas E., Scott R. Ekroth, and Christopher F. Hyer. “Intermediate-Term Results of Partial Plantar Fascia Release With Microtenotomy Using Bipolar Radiofrequency Microtenotomy.” The Journal of Foot and Ankle Surgery54.2 (2015): 179-182.(level of evidence: 3B)
- ↑ Chou, Andrew Chia Chen, et al. “Radiofrequency microtenotomy is as effective as plantar fasciotomy in the treatment of recalcitrant plantar fasciitis.” Foot and Ankle Surgery (2015). (Level of Evidence: 4)
- ↑ Hautmann, M. G., U. Neumaier, and O. Kölbl. “Re-irradiation for painful heel spur syndrome.” Strahlentherapie und Onkologie 190.3 (2014): 298-303. (level of evidence: 2B)
- ↑ Holtmann, Henrik et al. “Randomized Multicenter Follow-up Trial on the Effect of Radiotherapy for Plantar Fasciitis (painful Heels Spur) Depending on Dose and Fractionation – a Study Protocol.” Radiation Oncology (London, England) 10 (2015): 23. PMC. Web. 8 Jan. 2016. (level of evidence: 1B)
- ↑ Costantino, C., et al. “Cryoultrasound therapy in the treatment of chronic plantar fasciitis with heel spurs. A randomized controlled clinical study.” European journal of physical and rehabilitation medicine 50.1 (2014): 39-47. (level of evidence: 1B)
- ↑ E.K. Agyekum., “Heel pain: A systematic review”., Chinese Journal of Traumatology., 2015 (level of evidence: 1A)
- ↑ Cinar, E., F. Uygur, and S. Toprak Celenay. “AB1447-HPR The efficacy of low level laser therapy in the treatment of calcaneal spur.” Annals of the Rheumatic Diseases 71.Suppl 3 (2013): 757-757. (Level of Evidence: 4)
- ↑ Lee, Gregory P, John A. Ogden, and G. Lee Cross. “Effect of extracorporeal shock waves on calcaneal bone spurs.” Foot & ankle international 24.12 (2003): 927-930.
- ↑ Krischek O., “Symptomatic low-energy shockwave therapy in heel pain and radiologically detected plantar heel spur”., Z Orthop Ihre Grenzgeb., April 1998 (level of evidence: 1B)
- ↑ Yalcin E, “Effects of extracorporal shock wave therapy on symptomatic heel spurs: a correlation between clinical outcome and radiologic changes”, Rheumatol Int.; February 2012
- ↑ Chia KK., “Comparative trial of the foot pressure patterns between corrective orthotics, formthotics, bone spur pads and flat insoles in patients with chronic plantar fasciitis”., Ann Acad Med Singapore., October 2009 (level of evidence: 3A)
- ↑ Perhamre S1., “Sever’s injury: treatment with insoles provides effective pain relief”., Scand J Med Sci Sports., December 2011 (level of evidence: 1B)