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Related Experiment Video

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Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination
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Gastrocnemius tightness: A population based observational study.

Oliver Chan1, Karan Malhotra1, Olatunbosun Buraimoh1

  • 1Foot & Ankle Unit, Royal National Orthopaedic Hospital, Stanmore HA7 4LP, United Kingdom.

Foot and Ankle Surgery : Official Journal of the European Society of Foot and Ankle Surgeons
|October 17, 2018
PubMed
Summary

This study quantifies gastrocnemius tightness in healthy adults using a weight-bearing lunge test. Most people have some tightness, with values over 13° potentially indicating an abnormality.

Keywords:
Gastrocnemius tightnessWeightbearing lunge test

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Area of Science:

  • Musculoskeletal biomechanics
  • Orthopedic research
  • Sports medicine

Background:

  • Gastrocnemius tightness is linked to various musculoskeletal issues, including back pain and plantar fasciitis.
  • Surgical interventions for gastrocnemius tightness are increasing, yet objective definitions are lacking.
  • Quantifying gastrocnemius tightness in a general population is essential for defining contractures.

Purpose of the Study:

  • To establish an objective definition for gastrocnemius tightness.
  • To quantify gastrocnemius tightness in a large, healthy adult population.
  • To identify factors influencing gastrocnemius tightness.

Main Methods:

  • A weight-bearing lunge test was employed to measure ankle-foot dorsiflexion.
  • Maximal dorsiflexion was recorded with the knee extended and flexed at 20°.
  • The ankle-foot dorsiflexion index (ADI) was calculated and analyzed for distribution and demographic correlations.

Main Results:

  • 800 limbs from 400 participants were assessed, revealing a wide range of ankle-foot dorsiflexion.
  • The ankle-foot dorsiflexion index (ADI) ranged from 0-19°, approximating a normal distribution.
  • Mean ADI was 6.04±3.49°, positively correlated with age and negatively with physical activity.

Conclusions:

  • This study provides the first quantification of gastrocnemius tightness in a large healthy adult cohort.
  • A reproducible weight-bearing lunge test was defined for clinical and research use.
  • An ADI exceeding 13° (>2 SD of the mean) may indicate abnormal gastrocnemius tightness.