Treatment of lateral ankle instability with transfer of the extensor digitorum brevis muscle

Ankle sprains are the most common injuries sustained during sports and physical exercise. Treatment is usually conservative because most of these injuries heal without consequence. However, some injuries may be followed by chronic lateral pain and instability, and surgical stabilization is sometimes necessary. In select cases, there is little or no residual ligament or scar tissue remaining for late reconstruction. Proximal transfer of the origin of the extensor digitorum brevis muscle as a substitute for deficient ligament tissue can be used in these difficult cases. During the years 1971 to 1992, 13 ankles in 10 patients underwent surgery using the proximal extensor digitorum brevis muscle transfer method. At follow-up, all the ankles manifested functional stability and were stable with no clinical drawer sign. All had a normal range of motion in the ankle joint but showed a desired decreased supination range of motion throughout the hindfoot and ankle. The functional Karlsson scores were 84.5 +/- 18.8 before injury, 26.4 +/- 18.7 before surgery, and 83.6 +/- 18.7 at follow-up. Thus, the extensor digitorum brevis muscle transfer seems to be a useful alternative method of long-term ankle stabilization in these difficult chronic case; the results correlate well with a few other studies using this method.     

The muscle activation of the erector spinae during hyperextension with and without the pelvis restrained

The purpose of this study was to determine if pelvic restraint during hyperextension on a variable angle Roman chair (VARC) changes the muscle activation of the erector spinae musculature. Seventy volunteers (18–35 years) performed hyperextension exercises on the VARC with and without the pelvis restrained. Surface electromyography (EMG) was used to measure the muscle activation of the erector spinae at the third lumbar vertebra (L3). Total root mean square (RMS) for eccentric and concentric phases were amplitude normalized to a maximal voluntary isometric contraction (MVIC). A post test questionnaire was used to determine the subjective feeling of localized fatigue.The EMG data were analyzed with a Multivariate Hotelling's T² test and univariatet -tests. The questionnaire data were analyzed using McNemar's test. Alpha was set at 0·05. A statistically significant (p < 0·01) but small (approximately 3%) increase in the RMS of the erector spinae was demonstrated in the unrestrained condition for both independent variables: concentric and eccentric motion. Conversely, a greater proportion of participants subjectively reported greater effort in the lumbar extensors with the pelvis restrained. It is unclear if these observed changes in muscle activation and subjective perceptions can direct changes in the clinical practice.