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Comparative Study
. 2014 Jul 23:15:246.
doi: 10.1186/1471-2474-15-246.

The influence of knee position on ankle dorsiflexion - a biometric study

Sebastian F Baumbach  1 , Mareen Brumann, Jakob Binder, Wolf Mutschler, Markus Regauer, Hans Polzer
Affiliations
Comparative Study

The influence of knee position on ankle dorsiflexion - a biometric study

Sebastian F Baumbach et al. BMC Musculoskelet Disord. .

Abstract

Background: Musculus gastrocnemius tightness (MGT) can be diagnosed by comparing ankle dorsiflexion (ADF) with the knee extended and flexed. Although various measurement techniques exist, the degree of knee flexion needed to eliminate the effect of the gastrocnemius on ADF is still unknown. The aim of this study was to identify the minimal degree of knee flexion required to eliminate the restricting effect of the musculus gastrocnemius on ADF.

Methods: Bilateral ADF of 20 asymptomatic volunteers aged 18-40 years (50% female) was assessed prospectively at six different degrees of knee flexion (0°, 20°, 30°, 45°, 60°, 75°, Lunge). Tests were performed following a standardized protocol, non weightbearing and weightbearing, by two observers. Statistics comprised of descriptive statistics, t-tests, repeated measurement ANOVA and ICC.

Results: 20 individuals with a mean age of 27 ± 4 years were tested. No significant side to side differences were observed. The average ADF [95% confidence interval] for non weightbearing was 4° [1°-8°] with the knee extended and 20° [16°-24°] for the knee 75° flexed. Mean weightbearing ADF was 25° [22°-28°] for the knee extended and 39° [36°-42°] for the knee 75° flexed. The mean differences between 20° knee flexion and full extension were 15° [12°-18°] non weightbearing and 13° [11°-16°] weightbearing. Significant differences of ADF were only found between full extension and 20° of knee flexion. Further knee flexion did not increase ADF.

Conclusion: Knee flexion of 20° fully eliminates the ADF restraining effect of the gastrocnemius. This knowledge is essential to design a standardized clinical examination assessing MGT.

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Figures

Figure 1
Figure 1
Schematic illustration of the anatomical and testing principles of the relation between ankle dorsiflexion and the knee position.
Figure 2
Figure 2
Exemplary test procedure. A) Non weightbearing measurement; B) Weightbearing measurement; C) Lunge test; The image was taken by the authors and the shown persons gave informed consent for publishing their image.
Figure 3
Figure 3
Pooled data for mean ankle dorsiflexion and the mean differences between each increment of knee flexion presented as a box plot. Mean: Pooled mean values for ankle dorsiflexion; Dela: Differences between each step of knee flexion; ***: p < 0.001.
See this image and copyright information in PMC

References

    1. Patel A, DiGiovanni B. Association between plantar fasciitis and isolated contracture of the gastrocnemius. Foot Ankle Int. 2011;32:5–8. - PubMed
    1. DiGiovanni CW, Kuo R, Tejwani N, Price R, Hansen ST, Cziernecki J, Sangeorzan BJ. Isolated gastrocnemius tightness. J Bone Joint Surg Am. 2002;84-A:962–970. - PubMed
    1. Bolívar YA, Munuera PV, Padillo JP. Relationship between tightness of the posterior muscles of the lower limb and plantar fasciitis. Foot Ankle Int. 2013;34:42–48. - PubMed
    1. Irving DB, Cook JL, Menz HB. Factors associated with chronic plantar heel pain: a systematic review. J Sci Med Sport. 2006;9:11–22. discussion 23-14. - PubMed
    1. Crawford F, Thomson C. Interventions for treating plantar heel pain. Cochrane Database Syst Rev. 2003;3:CD000416. - PubMed

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