Research Review: Anterior Positional Fault of the Fibula after Sub-acute Lateral Ankle Sprains

Complete Reference: Hubbard TJ, Hertel J. Anterior Positional Fault of the Fibula after Sub-acute lateral Ankle Sprains. Manual Therapy. 2008; 13: 63-67.

Clinical Relevance:

Ankle sprains are the most common sports related injury. Unfortunately rehabilitation can be problematic and recurrent injury is possible. A significant side effect of an ankle sprain is decreased ankle dorsiflexion. Research has linked limited ankle dorsiflexion to recurrent ankle sprains, chronic knee injury, ACL tears, increased knee frontal plane movement and excessive femoral rotation. When implementing a recovery program for ankle sprains it would be conducive to perform distal fibular posterior mobilizations to regain lost ankle dorsiflexion.

Introduction:

Recent studies suggest a positional fault of the distal fibula on chronically injured ankles. Studies have not been done to evaluate fibular translation during sub-acute lateral ankle sprains. Additionally studies have not examined the relationship of ankle inflammation and fibular positional fault. Positional fault of the fibula can increase pain, and decrease talocrural dorsiflexion and sub talar range of motion. The purpose of this study is to examine fibular positional fault during sub-acute lateral ankle sprains and correlate positional fault with ankle swelling.

Methods:

Subjects:

  • 22 subjects (10 male, 12 female) recreationally active subjects.
    • 11 of 22 subjects (5 male, 6 female) with sub-acute lateral ankle sprains
    • 11 of 22 subjects (5 male, 6 female) with no history of previous ankle injury

Dependent Variables:

  • Fibula displacement measured with fluoroscope in relation to the tibia
  • Figure 8 tape measure method to evaluate swelling.

Instrumentation:

  • Mini 6600 Fluoroscope with a digital mobile C-Arm

Procedures:

  • Lateral fluoroscopic images taken with on both legs of the lateral ankle sprain (LAS) group and the control group. ┬áBolsters were added and a fluid inclinometer was utilized to ensure proper positioning.
  • Figure 8 measurement following Tatro-Adams, et al, 1995 to evaluate swelling. This was performed on both ankles of the LAS and control group.

Statistical Analysis:

  • Wilcoxon signed rank test was used to evaluate side-to-side differences within both LAS and control groups
  • Mann-Whitney tests to evaluate injured ankle of LAS group and same ankle of control group.
  • Mann-Whitney tests to evaluate uninjured ankle of LAS group and same ankle of the control group.
  • Pearson product moment calculated side-to-side difference in swelling and the corresponding fibular displacement

Results:

  • Wilcoxon signed rank test:
    • Significant differences within the ankles of the sub-acute LAS group (p=.008).
    • No significant difference within ankles of the healthy group (p=.563).
  • Mann-Whitney Test:
    • Significant difference between injured ankle and matched ankle of control group (p=.045)
    • No significant difference between uninjured ankle of LAS group and matched ankle of control group (p=.438)
  • Pearson Product moment:
    • Significant positive correlation of side to side differences in fibular position and swelling (r = 0.793, p = .004)
    • 63% of variance in the fibular position difference was explained by variance in ankle girth measurement.

Study Limitations:

  • Unknown if an altered fibular position existed prior to the injury.
  • Study does not indicate any literature review regarding possible translation of the tibia following ankle injury.
  • Study did not indicate whether subjects in the LAS group were excluded if they had previous injury on contralateral ankle.

Conclusion:

Statistically significant outcomes indicate the fibula takes on an anterior positional fault in sub-acute LAS. Effect sizes were .91 within the sub-acute LAS group and 1.15 between sub-acute involved ankle and control group. These indicate clinically meaningful effects. In addition, the greater the swelling, as indicated by ankle girth measurement, the greater the anterior positional fault of the fibula. Previous studies have been done on this topic. Recent studies indicate posterior or no translation of the fibula, however these studies measured fibular movement in relation to the talus. Mulligan, 1995 showed the talus also translates anteriorly following inversion ankle sprain, which can explain the findings of those recent studies.

One thought on “Research Review: Anterior Positional Fault of the Fibula after Sub-acute Lateral Ankle Sprains

  1. Pingback: The Ice-less Management of Acute Ankle Sprains | Stone Athletic Medicine

Leave a Reply

Your email address will not be published. Required fields are marked *