• 1.

    Rong K , Ge W & Li X et al.: Mid-term results of intramuscular lengthening of gastrocnemius and/or soleus to correct equinus deformity in flatfoot. Foot Ankle Int 36 : 1223, 2015.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 2.

    Riddle DL , Pulisic M & Pidcoe P et al.: Risk factors for plantar fasciitis: a matched case-control study. J Bone Joint Surg Am 85 : 872, 2003.

  • 3.

    Becker J , James S & Wayner R et al.: Biomechanical factors associated with Achilles tendinopathy and medial tibial stress syndrome in runners. Am J Sports Med 45 : 2614, 2017.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 4.

    Nakale NT , Strydom A & Saragas NP et al.: Association between plantar fasciitis and isolated gastrocnemius tightness. Foot Ankle Int 39 : 271, 2018.

  • 5.

    Searle A , Spink MJ & Chuter VH: Association between ankle equinus and plantar pressures in people with diabetes: a systematic review and meta-analysis. Clin Biomech 43 : 8, 2017.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 6.

    Gatt A & Chockalingam N: Clinical assessment of ankle joint dorsiflexion: a review of measurement techniques. JAPMA 101 : 59, 2011.

  • 7.

    Lindsjo U , Danckwardt-Lilliestrom G & Sahlstedt B: Measurement of the motion range in the loaded ankle. Clin Orthop Relat Res 199 : 68, 1985.

  • 8.

    Dalmau-Pastor M , Fargues-Polo B Jr, & Casanova-Martínez D Jr, et al.: Anatomy of the triceps surae: a pictorial essay. Foot Ankle Clin 19 : 603, 2014.

  • 9.

    DiGiovanni CW , Kuo R & Tejwani N et al.: Isolated gastrocnemius tightness. J Bone Joint Surg Am 84 : 962, 2002.

  • 10.

    Lichtwark GA & Wilson AM: Is Achilles tendon compliance optimised for maximum muscle efficiency during locomotion? J Biomech 40 : 1768, 2007.

  • 11.

    Hof AL , van Zandwijk JP & Bobbert MF: Mechanics of human triceps surae muscle in walking, running and jumping. Acta Physiol Scand 174 : 17, 2002.

  • 12.

    Chen IH , Kuo KN & Andriacchi TP: The influence of walking speed on mechanical joint power during gait. Gait Posture 6 : 171, 1997.

  • 13.

    Teixeira-Salmela LF , Nadeau S & Milot MH et al.: Effects of cadence on energy generation and absorption at lower extremity joints during gait. Clin Biomech 23 : 769, 2008.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 14.

    Graf A , Judge J & Ounpuu S et al.: The effect of walking speed on lower-extremity joint powers among elderly adults who exhibit low physical performance. Arch Phys Med Rehabil 86 : 2177, 2005.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 15.

    You JY , Lee HM & Luo HJ et al.: Gastrocnemius tightness on joint angle and work of lower extremity during gait. Clin Biomech 24 : 744, 2009.

  • 16.

    Orendurff MS , Segal AD & Aiona MD et al.: Triceps surae force, length and velocity during walking. Gait Posture 21 : 157, 2005.

  • 17.

    Moseley AM , Crosbie J & Adams R: High and low ankle flexibility and motor task performance. Gait Posture 18 : 73, 2003.

  • 18.

    Baddar A , Granata K & Damiano DL et al.: Ankle and knee coupling in patients with spastic diplegia: effects of gastrocnemius-soleus lengthening. Bone Joint Surg Am 84 : 736, 2002.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 19.

    Matjacic Z , Olensek A & Bajd T: Biomechanical characterization and clinical implications of artificially induced toe-walking: differences between pure soleus, pure gastrocnemius and combination of soleus and gastrocnemius contractures. J Biomech 39 : 255, 2006.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 20.

    Root ML , Orion WP & Weed JH: Normal and Abnormal Function of the Foot, Clinical Biomechanics Corp, Los Angeles, 1977.

  • 21.

    Lavery LA , Armstrong DG & Boulton AJM; Diabetex Research Group: Ankle equinus deformity and its relationship to high plantar pressure in a large population with diabetes mellitus. JAPMA 92 : 479, 2002.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 22.

    Frykberg RG , Bowen J & Hall J et al.: Prevalence of equinus in diabetic versus nondiabetic patients. JAPMA 102 : 84, 2012.

  • 23.

    Wrobel JS , Fleischer AE & Matzkin-Bridger J et al.: Physical examination variables predict response to conservative treatment of nonchronic plantar fasciitis: secondary analysis of a randomized, placebo-controlled footwear study. PM R 8 : 436, 2016.

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 24.

    Edwards WT: Effect of joint stiffness on standing stability. Gait Posture 25 : 432, 2007.

  • 25.

    McNamee MJ: Analysis of plantar fasciitis risk factors among intercollegiate and recreational runners: a matched case-control study [thesis], Texas State University, 2016.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 26.

    Huerta JP: The effects of the gastrocnemius on the plantar fascia. Foot Ankle Clin 19 : 701, 2014.

Prevalence and Distribution of Ankle Joint Equinus in 249 Consecutive Patients Attending a Foot and Ankle Specialty Clinic

Patrick A. DeHeer
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Sarah N. Standish
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Kyle J. Kirchner
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Adam E. Fleischer
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Background

The definition of equinus varies from less than 0° to less than 25° of dorsiflexion with the foot at 90° to the leg. Despite its pervasive nature and broad association with many lower-extremity conditions, the prevalence of ankle equinus is unclear. Furthermore, there are few data to suggest whether equinus is predominantly a bilateral finding or isolated to the affected limb only.

Methods

We conducted a prospective cohort study examining consecutive patients attending a single foot and ankle specialty practice. Participation involved an assessment of ankle joint range of motion by a single rater with more than 25 years of clinical experience. We defined ankle equinus as ankle joint dorsiflexion range of motion less than or equal to 0° and severe equinus as less than or equal to –5°. Patients who had previously experienced an Achilles tendon rupture, undergone posterior group lengthening (ie, Achilles tendon or gastrocnemius muscle lengthening), or had conservative or surgical treatment of equinus previously were excluded.

Results

Of 249 included patients, 61% were female and 79% nondiabetic. The prevalence of ankle equinus was 73% [183 of 249], and nearly all of these patients had bilateral restriction of ankle joint range of motion (prevalence of bilateral ankle equinus was 98.4% [180 of 183] among those with equinus). We also found that ankle equinus was more common in patients with diabetes, higher body mass indexes (BMIs), or overuse symptoms.

Conclusions

The prevalence of ankle equinus in this sample was higher than previously reported, and nearly all of these patients had bilateral involvement. These data suggest that many people attending foot/ankle specialty clinics will have ankle equinus, and select groups (diabetes, increased BMI, overuse symptoms) are increasingly likely.

Hoosier Foot and Ankle, Franklin, IN.

Fayette Podiatry, Brownsville, PA.

Podiatry Department, St Vincent Hospital, Indianapolis, IN.

Department of Research, Weil Foot and Ankle Institute and Dr. William M. Scholl College of Podiatric Medicine, North Chicago, IL.

Corresponding author: Patrick A. DeHeer, DPM, Hoosier Foot and Ankle, 1159 W Jefferson St, Suite 204, Franklin, IN 46131. (E-mail: padeheer@sbcglobal.net)
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