Using ultrasound to measure the fibre angle of vastus medialis oblique: a cadaveric validation study

Effect of applied cadence in repeated sprint cycling on muscle characteristics

PURPOSE

This study aimed to investigate physiological responses, muscle-tendon unit properties of the quadriceps muscle, and mechanical performance after repeated sprint cycling at optimal and 70% of optimal cadence.

METHODS

Twenty recreational cyclists performed as first sprint performance cycling test and during subsequent sessions two repeated sprint cycling protocols at optimal and 70% of optimal cadence, in random order. The muscle-tendon unit outcome measures on the dominant leg included muscle thickness, fascicle length (Lf), pennation angle (θp), and stiffness for the rectus femoris (RF), vastus lateralis (VL), and vastus medialis muscle (VM) at baseline, immediately after repeated sprint cycling, and 1-h post-exercise.

RESULTS

The results showed an increase in muscle thickness and θp in RF, VL, and VM for both cadences from baseline to immediately after exercise. The Lf decreased in RF (both cadences), while stiffness decreased in RF, VL, and VM at optimal cadence, and in VL at 70% of optimal cadence from baseline to immediately after exercise.

CONCLUSION

The present study revealed that the alterations in muscle characteristics were more marked after repeated sprint cycling at optimal cadence compared with a lower cadence most likely as a result of higher load on the muscle-tendon unit at optimal cadence.

Patellar malalignment: A common disorder associated with knee pain

Pain-associated knee joint disorders are common in daily life. Practically, knee pain should be divided into the origin from the isolated tibiofemoral (TF), isolated patellofemoral (PF) joint, or a combination thereof. The TF joint controls the actions of level walking, while the PF joint controls knee flexion-extension. Owing to its sufficient inherent stability, non-traumatic disorders of the isolated TF joint in young individuals are uncommon. In contrast, because of its insufficient inherent stability, non-traumatic disorders of the isolated PF joint are common in young individuals. Patellar malalignment (PM) associated with knee pain is common in all age groups, and the most common predisposing factor is imbalanced peripatellar soft-tissue tension. The outward forces acting on the patella are caused by pulling from the quadriceps femoris during knee flexion to extension (manifested by the quadriceps angle [Q-angle]), and sliding backward of the iliotibial band (ITB) during knee extension to flexion. Once the muscle power of the vastus medialis (especially the vastus medialis obliquus [VMO]) decreases, which lowers the counteracting effect against outward forces, the patella displaces or rotates laterally. The reduced contact surface between the patella and the femoral condyle significantly increases the compressive pressure and injures the articular cartilage. Subsequently, progressive PF degeneration occurs. Although other factors may also cause PM, they are relatively uncommon. In principle, nonsurgical treatment of PM should be considered first, while surgical treatment should follow established indications. Some nonsurgical techniques are currently widely used that feature high satisfaction rates. Surgical techniques are continuously being developed, and their success rates have gradually improved. This study aimed to review the current literature for relevant studies and report related publications of the author's institution to emphasize the universality and importance of PM management. Conceptually, simply focusing on problems of the TF joint cannot treat all knee disorders.

Ultrasound Measurement of Lateral Patellar Displacement: A Cadaveric Validation Study

Background

Patellofemoral pain syndrome (PFPS) is one of the most common musculoskeletal complaints seen in outpatient settings. It has been suggested that hip adduction creates loads on the iliotibial band and causes lateral displacement of the patella (patellar tilt), which can lead to uneven patellofemoral joint loading, and hence, cause patellofemoral pain. In previous studies in the literature, ultrasound has been used to measure lateral patellar displacement. However, the method lacks validity data.

Purpose/Hypothesis

The aim of this study was to validate the use of ultrasound to measure lateral displacement of the patella, by comparing the position of the patella as measured first by ultrasound, and then by direct measurement.

Study Design

Descriptive Laboratory Study.

Methods

Nine soft-fixed cadavers were used in this study. The cadavers had been donated for anatomical examination and research under the Human Tissue Act (2004). The distance between the lateral femoral condyle and the lateral edge of the patella were measured by B-mode real-time ultrasound, and then by direct measurement, in two positions, neutral and at 20° hip adduction.

Results

The mean difference in the patella-to-lateral femoral condyle distance in the neutral position and at 20° adduction was 0.27 cm (ultrasound), and 0.34 cm (direct measurement), respectively. There were no significant differences between the measurements obtained by US and by direct measurement (Pearson correlation= 0.97, p=0.83).

Conclusion

Ultrasound is a valid and reliable method for measuring patellar position relative to the femoral condyle, and the validity data reported here suggest that it can be used with confidence in clinic to assess lateral patellar displacement.

Level of Evidence

3.

The Effect of Self-Myofascial Release on the Pennation Angle of the Vastus Medialis Oblique and the Vastus Lateralis in Athletic Male Individuals: An Ultrasound Investigation

Background

Maintenance of patellar stability requires a balance between the vastus medialis oblique (VMO) and the vastus lateralis (VL). The imbalance between these muscles is thought to be implicated in the etiology of patellofemoral pain (PFP). Where there is hypertrophy of the VL in PFP patients, self-myofascial release (SMR) may be utilized for its management. However, there is no current evidence regarding SMR and its effects on VMO and VL architecture. The aim of this study, therefore, was to use ultrasound to gain further understanding of the effects of a program of SMR on the fiber angles of the VMO and VL.

Hypothesis

There will be a significant decrease in the pennation angles of the VMO and VL after seven weeks of SMR using a foam roller.

Study Design

Cohort Study.

Methods

Twenty-five young, athletic, male participants were recruited to use a foam roller, along the full length of both anterior thighs, three times weekly, on three separate days, for seven weeks. Ultrasound was used to determine the initial and final VMO and VL pennation angles on both limbs. One eligible participant was chosen as an intra-rater control and did not partake in the SMR regimen.

Results

There was a statistically significant (p < 0.001) decrease in the pennation angles of the VMO and VL after the SMR regime. Mean combined right and left VL angle change was -6.65° (-18% mean change) and the mean combined right and left VMO angle change was -7.65° (-11.5% mean change). A weak negative correlation was found between initial VMO fiber angle and the angle change (Rsquared = -0.21), as well as moderate negative correlation for the VL (Rsquared = -0.51).

Conclusion

A program of SMR on the anterior thighs of young, asymptomatic males resulted in changes to the fiber angles of both the VMO and VL. There was a significant decrease in pennation angle after seven weeks of SMR using a foam roller.

The effect of stretching exercises on the fibre angle of the vastus lateralis and vastus medialis oblique: an ultrasound study

[Purpose] To investigate the effects of a seven-week quadriceps stretching program on the muscle fibre orientation of the vastus medialis oblique and vastus lateralis in the lower limbs by ultrasound imaging. [Participants and Methods] Twenty-seven healthy, physically fit, asymptomatic females and males (age 21.5 ± 1.3, Tegner activity level score ≥4) were recruited. Their initial vastus medialis oblique and vastus lateralis fibre angles were determined using ultrasound. They then undertook a seven-week quadriceps stretching program, 3 sets of stretches to be performed on both lower limbs, 3 times a week on 3 separate days. One volunteer was assigned as an intra-rater control and did not take part in the stretching program. The vastus lateralis and vastus medialis oblique fibre angles were measured again on completion of the exercise regime. [Results] A statistically significant decrease in muscle fibre angle was observed in both the right and left vastus medialis oblique, and the right and left vastus lateralis. [Conclusion] A 7-week stretching program can result in a significant decrease in muscle fibre angle in both the vastus medialis oblique and the vastus lateralis. This can help in understanding the effects of prescribed stretching exercises on athletic patients with PFP.

Ultrasound investigation into the relationship between hip adduction and the patellofemoral joint

[Purpose] Patellofemoral pain (PFP) is a common musculoskeletal complaint. It has been suggested that hip adduction creates a load on the iliotibial band and causes lateral displacement of the patella (patella tilt). However, data gathered in a previous study were derived from a small sample of males, while the condition predominantly affects females. We assessed the relationship between hip adduction and patellar position with a larger sample size, including males and females. [Participants and Methods] Forty healthy, asymptomatic females and males (age 21.5 ± 1.3 years) were recruited. Their knees were passively flexed by 20°. Using ultrasound, the distance between the lateral edge of the patella and the lateral condyle of the femur was measured in the neutral position and at 20° adduction. [Results] Hip adduction produced a smaller patella-lateral femoral condyle measurement than in the neutral position. The mean difference in the patella-condyle distance between the neutral position and 20° hip adduction was 0.18 cm. No statistically significant difference was found between the right and left limbs, genders, Tegner scores, or BMI of the study participants. [Conclusion] The results of the study showed that hip adduction causes lateral displacement of the patella. Ultrasound is an effective means of assessing patella tilt.

Quadriceps architecture in individuals with patellofemoral pain: A systematic review

OBJECTIVES

To identify differences in architectural parameters (size, fiber/pennation angle, fiber length, and echogenicity) of the quadriceps muscle, as a whole or any individual part of it, using imaging techniques in individuals with patellofemoral pain (PFP) compared to contralateral, asymptomatic limb or separate control group.

BACKGROUND

Quadriceps muscles imbalance and weakness were proposed as risk factors for developing PFP. Although the muscle architecture (size, pennation/fiber angle and fiber length) is highly associated with skeletal muscle strength, it is not clear whether atrophy or any changes in architectural parameters of the quadriceps are presented in the PFP patients.

METHODS

Observational studies in which the total size of the quadriceps or individual parts of it were measured using imaging techniques in the PFP patients were included in this review. Electronic databases (PubMed, SCOPUS, PEDro, CINAHL, WOS, and EMBASE) were searched between January 1990 and December 2019 with no restriction of language. Study selection and data extraction and quality assessment were conducted by two independent reviewers.

RESULTS

Five cross-sectional studies were eligible to include in this review. Three out of five included studies that assessed the total size of the quadriceps and reported no significant differences between the PFP and healthy control group. Two out of five of the studies assessed the total size of the quadriceps between the symptomatic and asymptomatic limb of the PFP patients and reported the statistical difference between limbs. Only one study measured the fiber angle of the VMO muscle at the patella. Controversial results were found between studies that assessed the size of individual parts of the quadriceps.

CONCLUSION

Due to the controversial results of the included studies, this systematic review failed to draw a conclusion on the role of quadriceps atrophy in PFP pathology. The limitation in PFP literature considering pennation/fiber angle, echogenicity and fiber length of individual parts of the quadriceps muscle, rises the need for research that focuses on the biomechanical properties of the quadriceps in PFP patients.

Quadriceps architecture in individuals with patellofemoral pain: a systematic review protocol

OBJECTIVE

The objective of this review is to identify differences in quadriceps architectural parameters between healthy individuals and those with patellofemoral pain (PFP).

INTRODUCTION

Patellofemoral pain is one of the most common causes of knee pain among physically active populations. Muscular imbalance may play an important role in patellar malalignment or patellar maltracking. A systematic review will clarify the possible architectural changes of quadriceps muscles in persons with PFP.

INCLUSION CRITERIA

Eligible observational studies will include individuals younger than 50 years who have been diagnosed with unilateral or bilateral PFP. The comparator will be the contralateral, asymptomatic limb of the individual with PFP or a healthy matched subject. Studies that include measurement of quadriceps muscle size as the primary outcome will be considered. Studies in which participants had coexisting pathology, a history of lower limb surgery or injury, or pain originating from other joints will be excluded.

METHODS

PubMed/MEDLINE (NLM), Scopus, Embase, Physiotherapy Evidence Database, Web of Science and CINAHL databases and multiple gray literature sources will be searched. Studies published since 1 January 1990 will be considered; there will be no language restriction. Retrieval of full-text studies, assessment of methodological quality and data extraction will be performed independently by two reviewers. If possible, meta-analyses will be performed, and a Grading of Recommendations, Assessment, Development and Evaluation (GRADE) Summary of Findings presented.

Levator Ani avulsion: The histological composition of this site. A cadaveric study

INTRODUCTION

The sonographic appearance of a levator muscle "avulsion" representing the literal detachment of the pubovisceral muscle (PVM) enthesis has been contested. The nature of the levator ani "avulsion" is still not fully understood. It is known, that the tensile strength of a tendon is dependent on collagen with increased synthesis of collagen occurring in tissue with increased mechanical load levels. This study aims to perform a quantitative histological evaluation of the PVM enthesis with or without the imaging finding of levator ani "avulsion" to determine if there is a difference in the proportion of muscle and collagen.

METHOD

Three-dimensional translabial ultrasound for PVM "avulsion" was performed on cadavers using a GE Voluson I with a 5-9 MHz electronic probe. Cadavers were meticulously dissected to identify the presence or absence of an anatomical avulsion. The PVM enthesis was excised for further histopathological processing and treated with three different colorations. Quantitative analysis using ImageJ software was conducted to compare tissue composition in samples with or without sonographic "avulsion." All stages were performed by two separate investigators blinded to each other's results. The results were analyzed using SPSS v24, IBM.

RESULTS

Twenty-three PVM enthesis with histological staining were procured. Ultrasonographic "avulsions" were seen in 5/23 PVM enthesis. No anatomical avulsions were seen. There was no difference in the overall muscle or collagen content (Kruskal-Wallis, P = 0.864). The mean organized skeletal muscle content was 23% in the sonographic "avulsion" group versus 62% in the no "avulsion" group (Kruskall-Walis, P = 0.02). "Avulsions" were associated with a disorganized appearance at histology.

CONCLUSION

The tissue composition relating to the proportion of muscle and collagen was not significantly different in specimens with or without sonographic "avulsions." However, morphological differences were observed in the organization of the muscle fibres, which requires further evaluation.

Influence of knee joint position and sex on vastus medialis regional architecture

Ultrasound imaging was used to investigate vastus medialis (VM) architecture in 10 males and 10 females at different knee angles. Increase in muscle thickness occurs predominantly when the knee angle is changed from 0° (full extension) and 45° (p < 0.05); increases in VM pennation angle can be predominantly observed between 45° and 90° (p < 0.05). Sex differences in the VM architecture can be observed in the distal (p < 0.01) but not in the proximal region of the muscle (p > 0.11).

The effect of exercise on vastus medialis oblique muscle architecture: An ultrasound investigation

The vastus medialis oblique (VMO) is thought to be implicated in patellofemoral pain (PFP), and weakness in this portion of the vastus medialis muscle may lead to PFP. Management includes physiotherapy to strengthen the VMO. Although this intervention has been shown to be effective, the effects on the architecture of the muscle have not been investigated. This study aims to determine the changes in VMO architecture following a program of strengthening exercises. Twenty-one male participants underwent an initial ultrasound scan to measure the fiber angle and the insertion level of the VMO on the patella. Each subject then undertook a 6-week quadriceps femoris strengthening program; the scan and measurements were then repeated. A significant increase in VMO fiber angle and insertion length was observed. Average fiber angle increased by 5.24°; average insertion length increased by 2.7 mm. There was found to be a significant negative correlation between the initial values and the degree of change. Pearson's coefficient of correlation for measurements of patella length taken before and after exercise was 0.921, indicating a high degree of reliability. There was a significant positive correlation between fiber angle change and declared level of compliance (R(2)  = 0.796). The results reported here indicate that physiotherapy leads to a significant change in VMO morphology. Given the inverse correlation noted between initial architectural parameters and the degree of change, we suggest that patients who would benefit most from physiotherapy can be identified in clinic using a simple ultrasound technique. Clin. Anat. 29:752-758, 2016. © 2016 Wiley Periodicals, Inc.