The active knee extension test and Slump test in subjects with perceived hamstring tightness

Optimal cut-off values of the active knee extension test for diagnosing hamstring tightness

BACKGROUND

Active knee extension (AKE) is widely used to assess hamstring length, and an 'AKE >20°' is often used as the criterion for diagnosing tightness. However, the scientific evidence for this is unclear.

OBJECTIVE

This study measured and analysed AKE according to sex in two groups with different exercise participation levels to identify the appropriateness of current criteria.

METHODS

In the supine position, 90° flexion of the hip and knee joints was performed. The maximal knee extension was measured using a goniometer. Cut-off values for diagnosing hamstring tightness were calculated in three different ways as 'mean-1SD', 'mean-2SD', and 'mean-3SD'.

RESULTS

There were significant differences in AKE between groups and between sexes. In group A, representing normal healthy adults, cut-off values defined as mean-1SD and mean-2SD were 33.5° and 19.7° in male participants and 28.0° and 15.7° in female participants, respectively. There was a weak correlation between AKE and body mass index, but not between AKE and height and between AKE and weight.

CONCLUSION

This study found that the level of exercise participation significantly affects AKE, and female participants consistently had high flexibility regardless of exercise participation. Therefore, the current cut-off value, widely used in research and clinical settings, may not be a suitable criterion for diagnosing hamstring tightness.

The association of hamstring tightness with lumbar lordosis and trunk flexibility in healthy individuals: gender analysis

Objectives: The purpose of this study was to investigate if there is a relation between hamstring tightness and lumbar lordosis as well as trunk flexibility based on gender differences and to analyze the differences in hamstring tightness, lumber lordosis and trunk flexibility in healthy adults. Methods: One hundred young healthy adults were recruited and distributed into 2 equal groups according to gender: group A (female group) and group B (male group). Hamstring tightness (HT) was measured by Active Knee Extension (AKE) test and Straight Leg Raise (SLR) test, the angle of lumbar lordosis was measured with a flexible ruler from standing position and trunk flexion flexibility (TFF) was measured by Fingertip-to-Floor Test. Results: There was a significant correlation between TFF and both measures of HT (SLR, p = 0.001; AKE, p = 0.001) in females. While, there was a non-significant correlation in males (SLR, p = 0.900; AKE, p = 0.717). Moreover, there was a non-significant correlation between lumbar lordosis and HT measures in both groups as (p > 0.05). Furthermore, there were significant differences between males and females in hamstring flexibility, TFF and lumbar lordosis as (p < 0.05). Conclusion: Gender differences in the relationship between hamstring tightness and trunk flexion flexibility are significant. However, there was no significant difference between males and females in the relationship between hamstring tightness and lumbar lordosis.

Immediate Effects of Dry Needling as a Novel Strategy for Hamstring Flexibility: A Single-Blinded Clinical Pilot Study

CONTEXT

There are numerous studies on the benefits of dry needling (DN) for pain relief. No studies exist examining the effects of DN on hamstring flexibility.

OBJECTIVE

To determine the immediate effects of DN on hamstring flexibility in healthy subjects with shortened hamstrings.

DESIGN

A single-blinded, pretest-posttest clinical pilot study.

SETTING

A university physiotherapy clinic.

SUBJECTS

A total of 15 healthy subjects (female = 11; age = 23.26 [4.3] y) with shortened hamstrings participated in this study.

INTERVENTION

Subjects received a single session of DN. Three locations on the hamstring muscle group were needled, each for 1 minute.

MAIN OUTCOME MEASURES

The active knee extension test, muscle compliance, passive peak torque, and stretch tolerance were measured at baseline, immediately, and 15 minutes after DN.

RESULTS

There were statistically significant improvements in all outcome measures immediately after DN and at the 15-minute follow-up. The effect sizes for all outcome measures were large (Cohen's d ≥ 0.8). No serious adverse events were observed with DN.

CONCLUSIONS

This is the first study that demonstrates the beneficial effects of DN on hamstring flexibility, muscle compliance, and stretch tolerance without added stretching. The beneficial effects of DN should encourage clinicians to use DN as a novel strategy for increasing muscle flexibility.

Assessment of net knee moment-angle characteristics by instrumented hand-held dynamometry in children with spastic cerebral palsy and typically developing children

Background

The limited range of motion during walking in children with spastic cerebral palsy (SCP) may be the result of altered mechanical characteristics of muscles and connective tissues around the knee joint. Measurement of static net knee moment-angle relation will provide insights into these alterations, for which instrumented hand-held dynamometry may be applied.

The aims of this study were: (1) to test the measurement error of the estimated net knee moment-angle characteristics, (2) to determine the correlation between knee extension angle measurement at a standardized knee moment and popliteal angle from common physical examination and (3) to compare net knee moment–angle characteristics in SCP versus typically developing children.

Methods

With the child lying in sideward position, the knee was extended by moving the lower leg by a hand-held force transducer on a low friction cart. Force data were collected for a range of knee angles. Data were excluded when activity (EMG) levels of knee extensor and flexor muscles exceeded the EMG level during rest by more than two standard deviations. The net knee flexion moments were calculated from recorded force data and measured moment arm. Reliability for knee angles corresponding with 0.5, 1, 2, 3, and 4 Nm knee net flexion moments was assessed by standard error of measurements (SEM) and smallest detectable difference (SDD).

Results

For between day comparison, SEMs were about 5° and SDDs were below 14° for knee angles at 1-4 Nm net knee flexion moments. In SCP children, the knee angle measured at 4 Nm knee flexion moment was not related to the popliteal angle (r = 0.52). The slope at 4 Nm of the knee moment-angle curve in SCP children was significantly higher than that in typically developing children.

Conclusions

The presented knee hand-held dynamometry allows assessment of net knee flexion moment-knee angle characteristics in typically developing and SCP children and can be used to identify clinically relevant changes as a result of treatment. Overall stiffness of structures that contribute to the net knee flexion moment at the knee (i.e. muscles, tendons, ligaments) is elevated in SCP children.

Electronic supplementary material

The online version of this article (doi:10.1186/s12984-015-0056-y) contains supplementary material, which is available to authorized users.

Interrater and Intrarater Reliability of the Active Knee Extension (AKE) Test among Healthy Adults

[Purpose] The purpose of this study was to determine the reliability of the active knee extension (AKE) test among healthy adults. [Subjects] Fourteen healthy participants (10 men and 4 women) volunteered and gave informed consent. [Methods] Two raters conducted AKE tests independently with the aid of a simple and inexpensive stabilizing apparatus. Each knee was measured twice, and the AKE test was repeated one week later. [Results] The interrater reliability intraclass correlation coefficients (ICC_2,1) were 0.87 for the dominant knee and 0.81 for the nondominant knee. In addition, the intrarater (test-retest) reliability ICC_3,1 values range between 0.78–0.97 and 0.75–0.84 for raters 1 and 2 respectively. The percentages of agreement within 10° for AKE measurements were 93% for the dominant knee and 79% for the nondominant knee. [Conclusion] The finding suggests the current AKE test showed excellent interrater and intrarater reliability for assessing hamstring flexibility in healthy adults.

Upper Limb Neural Tension and Seated Slump Tests: The False Positive Rate among Healthy Young Adults without Cervical or Lumbar Symptoms

This study examined the false positive rate of the upper limb neural tension test (ULNTT) and seated slump test (SST) among healthy young adults with no history of cervical, lumbar, or peripheral symptoms. Eighty-four subjects (27 men and 57 women) with a mean age of 22.9 years participated in the investigation. All participants completed a screening questionnaire designed to exclude subjects with a history of cervical or lumbar spine pain or injury, or upper or lower extremity neurological symptoms. The ULNTT and the SST were performed on the left upper and lower extremity of each participant. Of the 84 participants tested, 73 (86.9%) were found to have a positive ULNTT at some point in the available range of elbow extension. Twenty-eight (33.3%) of the 84 subjects had a positive SST at some point in the available range of knee extension. The mean knee extension angle for those subjects with a positive SST was 15.1 degrees with a 95% confidence interval (CI) of 12.3 and 19.7 degrees . The mean elbow extension angle for those with a positive ULNTT was 49.4 degrees with a 95% CI of 44.8 and 54.0 degrees . The number of positive tests for both the ULNTT and the SST was found to be high in this sample of asymptomatic healthy young adults. Based on the results of this investigation, the authors suggest that the current criteria for determining a positive test for both the ULNTT and the SST should be examined using the proposed range of motion cut-off scores.

Slump test: sensory responses in asymptomatic subjects

The Slump Test is used as a fast, low-cost diagnostic tool in the evaluation of leg and back pain disorders. The purpose of this study was to identify the normative sensory responses to the Slump Test in asymptomatic subjects. Eighty-four subjects were tested using a standardized procedure by the same examiner to ensure consistency. Prevalence, intensity, location, and nature of responses at each stage of the Slump Test [Slumped Sitting (SS), Knee Extension (KE), Ankle Dorsiflexion (AD), and Cervical Extension (CE)] were recorded. Of the subjects, 97.6% reported a sensory response during the Slump Test. Prevalence of responses increased significantly from 29.8% at SS to 94% at KE and decreased significantly from 97.6% at AD to 65.5% at CE. Median intensity of responses increased significantly from 0/10 at SS, through 4/10 at KE, to 6/10 at AD, and then decreased significantly to 2/10 at CE. At SS, responses were located at the back or neck, but during the subsequent stages, responses were located most commonly in the posterior thigh, knee, and calf. In terms of nature, a number of different descriptors were used, the most common being "stretch," "tight," and "pull." Approximately 80% of subjects reporting a response had complete or partial relief of this response following cervical extension, indicating that the normal response to the Slump Test may be considered a neurogenic response. This normative data may be used as a reference point when using the Slump Test in the examination of leg and back pain disorders.