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Carrie L Docherty

Publications and source records attributed to Carrie L Docherty.

3 recordsLinked to original sources

Bracing and rehabilitation--what's new.

Based on the recent evidence, ankle bracing and taping do appear to have positive effects on ankle support. For example, both bracing and taping restrict inversion range of motion, with tape and stirrup-style braces providing the best support. Although exercise reduces this restriction, the range remains consistent with levels considered to be within the normal range. Ankle supports also appear to improve the strength of the muscular response to perturbation, potentially providing a stronger muscular contraction. In contrast, ankle supports fail to improve the neuromuscular response time to unexpected perturbations. Thus, it appears that the stronger response may occur too slowly to protect the joint. This slowness of the neuromuscular response, however, may be offset by the support's ability to slow the inversion motion. The slowing of inversion appears to allow the neuromuscular system to respond at or before the point of ligament damage. Finally, ankle supports appear to improve balance only in individuals with previously injured ankles. This suggests that supports may have a selective effect in protecting injured but not uninjured individuals. Despite these positive effects, some cautions should be emphasized. First, most of the studies cited have been performed in the laboratory setting with joint velocities and loads much below what are encountered in the athletic and daily activities. Whether tape and braces can maintain their effectiveness under the more extreme conditions of functional activities remains unclear. Additionally, some evidence suggests that ankle supports may transfer loads to other joints putting them at risk for injury. Thus, further study is needed to determine the risk-to-benefit ratio of ankle supports. Finally, much of the research presented has been done only on uninjured ankles. Based on the current evidence, it seems possible that the effectiveness of ankle supports may differ depending on the population, and it seems clinically important to know whether we can expect the same results for injured and uninjured ankles. Proper and early rehabilitation is important in preventing residual ankle symptoms. Reports indicate that up to 73% of people who sustain a lateral ankle sprain have recurrent sprains, but it is unknown how many of these participants partake in rehabilitation. Proper immobilization and acute care of the injured ankle is imperative. An immobilization boot or strapping that can be removed during early non-weight bearing exercises seems to be most effective. Strength and balance training of the uninjured contralateral limb can be used to assist reaching full recovery in a shorter period of time. Functional exercises can also be performed earlier in the rehabilitation process by reducing the gravitational forces so patients can perform in a pain-free range and still receive the benefits of early activity. Evidence shows that daily ankle disk training assists in preventing ankle sprains, and is a relatively inexpensive and easy alternative to traditional rehabilitation protocols.

Ankle Injuries↗

Relationship between two proprioceptive measures and stiffness at the ankle.

Previous research has investigated the role of proprioception and stiffness in the control of joint stability. However, to date, no research has been done on the relationship between proprioception and stiffness. Therefore, the purpose of this study was to determine the relationship between force sense, joint reposition sense, and stiffness at the ankle. A heterogeneous sample was obtained for this study; 20 of the 40 participants had a history of ankle sprains, and 13 of the 20 had been diagnosed by a physician (two mild ankle sprains, seven moderate sprains, four severe sprains). All subjects were asymptomatic and active at the time of the study. Active joint reposition sense was measured using a custom-built ankle goniometer, force sense was measured unilaterally and contralaterally with a load cell, and ankle muscle stiffness was measured via transient oscillation using a custom-built inversion-eversion cradle. We found no significant correlations between stiffness and joint reposition sense, with values of r ranging from 0.01 to 0.21. Significant correlations were found between stiffness and force sense. Specifically, contralateral force sense reproduction was significantly correlated to stiffness in the injured or "involved" ankle (r's ranging from 0.47 to 0.65; P< or =0.008). Whether the decreased ability to appropriately sense force (increased error) sends information to the central nervous system to increase muscle stiffness in response to an unexpected loss of stability, or whether these two phenomena function independently and both change concurrently as a result of injury to the system requires further investigation.

Adult↗

Chronic Ankle Instability Does Not Affect Lower Extremity Functional Performance.

OBJECTIVE: To determine if functional performance is impaired in individuals with self-reported chronic ankle instability. DESIGN AND SETTING: We used a between-groups design to assess 3 functional variables. All data were collected at a Division III college and a military academy. Before testing, all subjects performed a 5-minute warm-up, followed by a series of stretches for the lower extremity muscles. Subjects then performed cocontraction, shuttle run, and agility hop tests in a counterbalanced fashion. Three trials for each functional test were completed and averaged for analysis. SUBJECTS: Twenty men with a history of at least 1 significant ankle sprain and episodes of at least 1 repeated ankle injury or feelings of instability or "giving way" were compared with 20 men with no prior history of ankle injury. Subjects were matched by age, height, weight, and activity level. MEASUREMENTS: Time to completion was measured in seconds for the cocontraction and the shuttle run tests. The agility hop test was measured on an error point scale. RESULTS: Using 3 separate, independent, 2-tailed t tests, we found no significant difference between groups for the cocontraction (P =.452), shuttle run (P =.680), or agility hop (P =.902) tests. CONCLUSIONS: Chronic ankle instability is a subjectively reported phenomenon defined as the tendency to "give way" during normal activity. Although athletes commonly complain of subjective symptoms associated with chronic ankle instability, our findings suggest that these symptoms do not negatively influence actual functional performance. Future researchers should evaluate other, more demanding functional-performance tests to further substantiate these findings.

Journal Article↗