We would like to thank Jakob Binder for his help in subject acquisition and organization of the examinations, Mrs. Hella Thun for designing Figure 1 and 2 and finally Mr. Dipl.-Ing. (FH), M.Sc. M. Saller for his statistical support.

Ethics statement: The study was approval by the local ethics committee of the University of Munich (# 007-14).
Note: An examination couch freely accessible on both sides and the foot end is required for non-weightbearing testing. A line (tape, approximately 2 meters) on the ground perpendicular the wall is needed for weightbearing testing. A standard goniometer with 2&#176; increments and 20 cm length is used. We recommend documenting the results using a standardized fourfold table containing ADF measurement for the knee extended and flexed for each leg separately.
1. Participant Preparation
<ol>
	<li>Have the subject take off their pants and remove their footwear.</li>
	<li>Mark the axis of the fibula by drawing a line connecting the center of the distal fibula 5 cm and 15 cm above the tip of the fibula.</li>
</ol>
2. Non-weightbearing Measurement (Figure 2A)&#160;
<ol>
	<li>Have two investigators perform the measurement, one conducting the test, the other measuring the degree of ankle dorsiflexion.</li>
	<li>Place the subject in supine position on the examination couch. The examination couch must be freely accessible on both sides and the foot end.</li>
	<li>Have the first investigator place one hand at the level of the subtalar joint to ensure a neutral pronation-supination position of the rear foot and place the other hand around the midfoot. Thereby one hand stabilizes the talonavicular joint, while the other hand applies force on the plantar aspect of the forefoot to achieve maximum ankle dorsiflexion.</li>
	<li>Have the first investigator ensure that the knee is fully extended.</li>
	<li>Have the second investigator perform the measurement of the ankle dorsiflexion using a goniometer. Place one arm of the goniometer connecting the start and end point of the previously marked axis of the fibula. Align the other arm with the plantar aspect of the foot.</li>
	<li>Note the result on the documentation sheet.</li>
	<li>Have the first investigator ensure 90&#176; of knee flexion by placing one hand on the distal dorsal aspect of the thigh while the other hand applies force on the plantar aspect of the forefoot to achieve maximum ankle dorsiflexion.</li>
	<li>Have the first investigator place one hand at the level of the subtalar joint to ensure a neutral pronation-supination position of the rear foot and place the other hand around the midfoot. Thereby one hand stabilizes the talonavicular joint and the other hand applies force on the plantar aspect of the forefoot to achieve maximum ankle dorsiflexion.</li>
	<li>Have the second investigator perform the measurement of the ankle dorsiflexion using a goniometer. Place one arm of the goniometer connecting the start and end point of the previously marked axis of the fibula. Align the other arm with the plantar aspect of the foot.</li>
	<li>Note the result on the documentation sheet.</li>
	<li>Repeat steps 2.1 through 2.10 for the contralateral side.</li>
</ol>
3. Weightbearing Measurement (Figure 2B)
<ol>
	<li>Have one investigator perform the test.</li>
	<li>Place the subject standing opposite a wall.</li>
	<li>Have the subject get into the lunge position with the leg to be measured being the rear leg.</li>
	<li>Have the investigator help the subject to place his/her rear foot centered on the previously marked line. Ensure that the heel and the second toe of the rear leg are centered on the line.</li>
	<li>Have the subject hold onto the wall in order to stabilize their stance.</li>
	<li>Have the subject fully extend their rear leg. Have the investigator ensure that the knee is fully extended. Be aware that even slight knee flexion significantly influences ankle dorsiflexion.</li>
	<li>Have the subject move their hip towards the wall until just before heel lift off of the rear leg. The front leg can be flexed as needed / as comfortable.</li>
	<li>Have the investigator place one hand on the dorsal aspect of the subtalar joint to ensure a neutral pronation-supination position of the rear foot.</li>
	<li>Have the investigator perform the measurement of ankle dorsiflexion with the other hand. Align one arm of the goniometer connecting the start and end point of the previously marked axis of the fibula. Place the other arm on the floor.</li>
	<li>Note the result on the documentation sheet.</li>
	<li>Have the subject get into the lunge position with the leg to be measured being the rear leg. Therefore have the patient move towards the wall until a comfortable position has been reached.</li>
	<li>Have the investigator help the subject to place his/her rear foot centered on the previously marked line. Ensure that the heel and the second toe of the rear leg are centered on the line.</li>
	<li>Have the subject hold onto the wall in order to stabilize their stance.</li>
	<li>Have the subject flex the rear leg as comfortable and move their hip towards the wall until just before heel lift off of the rear leg. The front leg can be flexed as needed / as comfortable.</li>
	<li>Have the investigator ensure that the rear knee is flexed at least 20 degrees. In case of doubt use the goniometer to ensure knee flexion greater than 19 degrees.</li>
	<li>Have the investigator place one hand on the dorsal aspect of the subtalar joint to ensure a neutral pronation-supination position of the rear foot.</li>
	<li>Perform the measurement of ankle dorsiflexion with the other hand. Align one arm of the goniometer connecting the start and end point of the previously marked axis of the fibula. Place the other arm on the floor.</li>
	<li>Note the result on the documentation sheet.</li>
	<li>Repeat steps 3.1 through 3.18 for the contralateral side.</li>
</ol>
4. Data Analysis and Interpretation
<ol>
	<li>Ask the subject to identify the symptomatic side.</li>
	<li>Review the ADF data on the documentation sheet.
	<ol>
		<li>First identify whether ADF with the knee extended is less than 10&#176; on the symptomatic side. If so, consider MGT to be a possible cause. Then, compare ADF with the knee extended and flexed. If knee flexion results in a significant increase of ADF, MGT is present.</li>
		<li>In case ADF is greater than 10&#176;, compare ADF with the knee extended between both legs. If ADF is reduced on the symptomatic compared to the non-symptomatic side consider MGT to be a possible cause. If knee flexion on the symptomatic side results in a significant increase of ADF, MGT is present.</li>
	</ol>
	</li>
</ol>

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The authors have nothing to disclose. 
A biometric version of this study has been published 17. The herein presented paper focuses on the actual conduct of the clinical examinations for isolated MGT. The findings of the biometric paper 17 on the influence of the degree of knee flexion are implanted in this paper.

Examinations on 20 healthy individuals revealed, that 20 degrees of knee flexion already eliminates the influence of the M. gastrocnemius on ADF. Further knee flexion resulted in no significant ADF increase. The herein presented video description of a standardized non-weightbearing and weightbearing examination for MGT builds the prerequisite for future studies establishing physiological norm values.
The study has limitations. First, no custom-made measurement device was used to asses...

Limited ankle dorsiflexion (ADF) alters the gait kinematics and is held responsible for common foot pathologies including Achilles tendinopathy, stress fractures, metatarsalgia and plantar heel pain 1-5. The most common cause for limited ADF is isolated Musculus gastrocnemius tightness (MGT) 3,6.
The joint kinematics of the ankle are influenced by knee flexion as the M. gastrocnemius bridges both joints. The muscle is under tension when the knee is fully extended, as the origin of the muscle is then furthest proximal. The M. gastrocnemius then restrains ADF. Knee flexion approximates the muscle&#39;s origin, thereby reducing the tension of the M. gastrocnemius, and consequently increases ADF. Ankle dorsiflexion is then limited by other anatomical structures of the ankle joint. Figure 1 illustrates this principle. In the case of MGT, ADF is limited with the knee fully extended but substantially increases by flexion of the knee 4.
Clinical examination for MGT takes advantage of the above outlined principled and was first published in 1923 by Silfverski&#246;ld, a Swedish orthopedic surgeon 7. Since then, numerous examination techniques have been described, all of which compare the ADF with the knee extended and flexed. Published clinical tests can be categorized into non-weightbearing 5,8, weightbearing 9,10, and instrumented 11,12. Today, non-weightbearing examination is most commonly conducted 13. The patient is placed supine on the examination couch and ADF is assessed with the knee fully extended and typically 90&#176; flexed (Figure 2A). On the contrary, weightbearing ADF measurements are conducted with the subject upright in lunge stance. The rear knee is extended or bent and the subject is asked to lean forward just before heel liftoff (Figure 2B). For both tests MGT is diagnosed, if the ADF with the knee extended is impaired and knee flexion results in a significant increase of ADF.
Although non-weightbearing tests are frequently performed, weightbearing testing has several advantages. First, only one investigator is needed for weightbearing examination, whereas two examiners are required to achieve reliable non-weightbearing measurements. Second, the weightbearing examination more closely reflects the load during gait. Third, the force applied to the ankle is independent of the examiner. Fourth, weightbearing examination features a higher intra- and inter- rater reliability 9,10,13-15.
The major limitation of all tests for MGT is that&#160;the minimal degree of knee flexion needed to eliminate the restraining effect of the M. gastrocnemius on ADF is unknown 8,15. Whereas 90&#176; of knee flexion are typically applied in non-weightbearing testing 5,8,16, this is not feasible for the weightbearing examination. The broad population is unable to perform a Lunge with 90&#176; of knee flexion without lifting the heel off the ground. Consequently, most studies conducting weightbearing examinations did not control for knee flexion 8,15. In order to perform reliable weightbearing examinations it is essential to identify the minimal degree of knee flexion needed to eliminate the restraining effect of the M. gastrocnemius on ADF.
Overall, literature argues for weightbearing testing for the diagnosis of MGT. In order to provide a valid weightbearing examination procedure, the minimal degree of knee flexion required to eliminate the ADF restraining effect of the M. gastrocnemius must be known. The aim of this study was to investigate the influence of knee flexion on ADF in non-weightbearing and weightbearing testing and to provide a step-by-step guide to conduct non-weightbearing and weightbearing examination for MGT.

<table><tbody><tr><td>Examination couch</td><td></td><td></td><td></td></tr><tr><td>Standard goniometer&amp;nbsp;</td><td>MDF Instruments USA, Inc. Malibu, CA, USA</td><td></td><td>2&amp;deg; increments</td></tr></tbody></table>

diagnosis of musculus gastrocnemius tightness - key factors for the clinical examination

Common foot and ankle pathologies have been linked to isolated Musculus gastrocnemius tightness (MGT). Various examination techniques have been described to assess MGT. Still, a standardized examination procedure is missing. Literature argues for weightbearing examination but the degree of knee flexion needed to eliminate the restraining effect of the M. gastrocnemius on ankle dorsiflexion (ADF) is unknown. This manuscript investigates the effect of knee flexion on ankle dorsiflexion and provides a detailed description of a standardized examination protocol. Examination on 20 healthy individuals revealed, that 20&#176; of knee flexion is sufficient to fully eliminate the influence of the M. gastrocnemius on ADF. This builds the prerequisite for a standardized examination for MGT. Non-weightbearing and weightbearing examination of ADF has to be conducted with the knee fully extended and at least 20&#176; flexed. Two investigators should conduct non-weightbearing testing with the subject in supine position. In order to obtain reliable results, the axis of the fibula should be marked. One examiner can conduct weightbearing examination with the subject in lunge stance. Isolated MGT is present if ADF is impaired with the knee fully extended and knee flexion results in a significant ADF increase. The herein presented standardized examination is the prerequisite for future studies aiming at establishing norm values.

Both ankles of 20 healthy individuals (mean age of 27.1 ± 3.9 years), 50% female, were examined. Non-weightbearing and weightbearing tests at six different degrees of knee flexion (full extension, 20°, 30°, 45°, 60°, 75°) and the Lunge Test (uncontrolled knee flexion) were conducted. A functional brace was used to control knee flexion. Measurements were performed by two investigators blinded to each other's results. Between each individual, the order of the investigators and the ord...

Watch this Scientific Journal Video about Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination at JoVE.com

Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination

Isolated Musculus gastrocnemius tightness is a common cause for foot and ankle pathologies. Currently no standardized examination procedure exists. This manuscript demonstrates that 20 degree of knee flexion eliminates the restraining effect of the M. gastrocnemius on ankle dorsiflexion and presents a video description of a standardized examination protocol.

Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination

Common foot and ankle pathologies have been linked to isolated Musculus gastrocnemius tightness (MGT). Various examination techniques have been described ...

diagnosis-musculus-gastrocnemius-tightness-key-factors-for-clinical

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Medicine

14.1K Views.  Munich University Hospital. Isolated Musculus gastrocnemius tightness is a common cause for foot and ankle pathologies. Currently no standardized examination procedure exists. This manuscript demonstrates that 20 degree of knee flexion eliminates the restraining effect of the M. gastrocnemius on ankle dorsiflexion and presents a video description of a standardized examination protocol.

Video: Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination

Manual Muscle Testing:  A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients 

Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, and persistent nerve and muscle impairments after hospital discharge.1-6 Using an explicit protocol with a structured approach to training and quality assurance of research staff, manual muscle testing (MMT) is a highly reliable method for assessing strength, using a standardized clinical examination, for patients following ARDS, and can be completed with mechanically ventilated patients who can tolerate sitting upright in bed and are able to follow two-step commands. 7, 8 
This video demonstrates a protocol for MMT, which has been taught to &ge;43 research staff who have performed &gt;800 assessments on &gt;280 ARDS survivors. Modifications for the bedridden patient are included. Each muscle is tested with specific techniques for positioning, stabilization, resistance, and palpation for each score of the 6-point ordinal Medical Research Council scale.7,9-11 Three upper and three lower extremity muscles are graded in this protocol: shoulder abduction, elbow flexion, wrist extension, hip flexion, knee extension, and ankle dorsiflexion. These muscles were chosen based on the standard approach for evaluating patients for ICU-acquired weakness used in prior publications. 1,2.

Manual Muscle Testing:  A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients

Survivors of acute respiratory distress syndrome (ARDS) and critical illness frequently develop long-lasting muscle weakness. Manual muscle testing (MMT) is a standardized clinical examination commonly used to measure strength of peripheral skeletal muscle groups. This video demonstrates MMT using the 6-point Medical Research Council scale.

Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, ...

Assessment of Neuromuscular Function Using Percutaneous Electrical Nerve Stimulation

Percutaneous electrical nerve stimulation is a non-invasive method commonly used to evaluate neuromuscular function from brain to muscle (supra-spinal, spinal and peripheral levels). The present protocol describes how this method can be used to stimulate the posterior tibial nerve that activates plantar flexor muscles. Percutaneous electrical nerve stimulation consists of inducing an electrical stimulus to a motor nerve to evoke a muscular response. Direct (M-wave) and/or indirect (H-reflex) electrophysiological responses can be recorded at rest using surface electromyography. Mechanical (twitch torque) responses can be quantified with a force/torque ergometer. M-wave and twitch torque reflect neuromuscular transmission and excitation-contraction coupling, whereas H-reflex provides an index of spinal excitability. EMG activity and mechanical (superimposed twitch) responses can also be recorded during maximal voluntary contractions to evaluate voluntary activation level. Percutaneous nerve stimulation provides an assessment of neuromuscular function in humans, and is highly beneficial especially for studies evaluating neuromuscular plasticity following acute (fatigue) or chronic (training/detraining) exercise.

We present a protocol to assess changes in neuromuscular function. Percutaneous electrical nerve stimulation is a non-invasive method that evokes muscular responses. Electrophysiological and mechanical properties of these responses permit the evaluation of neuromuscular function from brain to muscle (supra-spinal, spinal and peripheral levels).

Percutaneous electrical nerve stimulation is a non-invasive method commonly used to evaluate neuromuscular function from brain to muscle (supra-spinal, ...

Neuroscience

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations

Many hamstring injuries that occur during physical activity occur while the muscles are lengthening, during eccentric hamstring muscle actions. Opposite of these eccentric hamstring actions are concentric quadriceps actions, where the larger and likely stronger quadriceps straighten the knee. Therefore, to stabilize the lower limbs during movement, the hamstrings must eccentrically combat against the strong knee-straightening torque of the quadriceps. As such, eccentric hamstring strength expressed relative to concentric quadricep strength is commonly referred to as the &#34;functional ratio&#34; as most movements in sports require simultaneous concentric knee extension and eccentric knee flexion. To increase the strength, resiliency, and functional performance of the hamstrings, it is necessary to test and train the hamstrings at different eccentric speeds. The main purpose of this work is to provide instructions for measuring and interpreting eccentric hamstring strength. Techniques for measuring the functional ratio using isokinetic dynamometry are provided and sample data will be compared. Additionally, we briefly describe how to address hamstring strength deficiencies or unilateral strength differences using exercises that specifically focus on increasing eccentric hamstring strength.

The hamstrings are a group of muscles that are sometimes problematic for athletes, resulting in soft tissue injury in the lower limbs. To prevent such injuries, functional training of the hamstrings requires intensive eccentric contractions. Additionally, hamstring function should be tested in relation to quadricep function at different contraction speeds.

Many hamstring injuries that occur during physical activity occur while the muscles are lengthening, during eccentric hamstring muscle actions. Opposite ...

Evaluation of Muscle Function of the Extensor Digitorum Longus Muscle Ex vivo and Tibialis Anterior Muscle In situ in Mice

Body movements are mainly provided by mechanical function of skeletal muscle. Skeletal muscle is composed of numerous bundles of myofibers that are sheathed by intramuscular connective tissues. Each myofiber contains many myofibrils that run longitudinally along the length of the myofiber. Myofibrils are the contractile apparatus of muscle and they are composed of repeated contractile units known as sarcomeres. A sarcomere unit contains actin and myosin filaments that are spaced by the Z discs and titin protein. Mechanical function of skeletal muscle is defined by the contractile and passive properties of muscle. The contractile properties are used to characterize the amount of force generated during muscle contraction, time of force generation and time of muscle relaxation. Any factor that affects muscle contraction (such as interaction between actin and myosin filaments, homeostasis of calcium, ATP/ADP ratio, etc.) influences the contractile properties. The passive properties refer to the elastic and viscous properties (stiffness and viscosity) of the muscle in the absence of contraction. These properties are determined by the extracellular and the intracellular structural components (such as titin) and connective tissues (mainly collagen) 1-2. The contractile and passive properties are two inseparable aspects of muscle function. For example, elbow flexion is accomplished by contraction of muscles in the anterior compartment of the upper arm and passive stretch of muscles in the posterior compartment of the upper arm. To truly understand muscle function, both contractile and passive properties should be studied.
The contractile and/or passive mechanical properties of muscle are often compromised in muscle diseases. A good example is Duchenne muscular dystrophy (DMD), a severe muscle wasting disease caused by dystrophin deficiency 3. Dystrophin is a cytoskeletal protein that stabilizes the muscle cell membrane (sarcolemma) during muscle contraction 4. In the absence of dystrophin, the sarcolemma is damaged by the shearing force generated during force transmission. This membrane tearing initiates a chain reaction which leads to muscle cell death and loss of contractile machinery. As a consequence, muscle force is reduced and dead myofibers are replaced by fibrotic tissues 5. This later change increases muscle stiffness 6. Accurate measurement of these changes provides important guide to evaluate disease progression and to determine therapeutic efficacy of novel gene/cell/pharmacological interventions. Here, we present two methods to evaluate both contractile and passive mechanical properties of the extensor digitorum longus (EDL) muscle and the contractile properties of the tibialis anterior (TA) muscle.

Evaluation of Muscle Function of the Extensor Digitorum Longus Muscle Ex vivo and Tibialis Anterior Muscle In situ in Mice

Changes in limb muscle contractile and passive mechanical properties are important biomarkers for muscle diseases. This manuscript describes physiological assays to measure these properties in the murine extensor digitorum longus and tibialis anterior muscles.

Body  movements are mainly provided by mechanical function of skeletal muscle. Skeletal  muscle is composed of numerous bundles of myofibers that are ...

Biology

Ultrasound Evaluation of Achilles Tendon Morphology

Measurement of Healthy and Injured Triceps Surae Morphology

Achilles tendon injuries occur throughout the lifespan and can negatively affect quality of life and overall health. Achilles tendinopathy is generally classified as an overuse injury associated with fusiform tendon thickening, neovascularization, and interstitial tendon degeneration. Current literature suggests these structural changes are associated with&#160;symptoms and lower physical activity levels, as well as&#160;symptoms and lower extremity function in the long term. Surgically and non-surgically managed Achilles tendon ruptures result in increased tendon cross-sectional area (CSA) and a lengthened Achilles tendon. Both structural outcomes have clinical implications, as larger CSA positively predicts function, whereas increased tendon lengthening predicts reduced function after Achilles tendon rupture. Given the relationship between structural changes associated with Achilles tendon injuries for both injury severity and injury recovery, it is critical to be able to quantify Achilles tendon structure reliably and accurately. Silbernagel&#39;s group has established a valid and reliable method for efficiently evaluating triceps surae muscle and tendon structure. In this protocol, B-mode musculoskeletal ultrasound imaging is used to measure triceps surae structure, including Achilles tendon thickness and CSA, soleus thickness, and the presence of additional findings (calcifications and bursitis). B-mode extended field-of-view is used to measure Achilles tendon length and gastrocnemius anatomical CSA. Finally, power Doppler is used to identify intratendinous neovascularization. Quantification of triceps surae structure allows for comparison between limbs as well as longitudinal changes in response to exercise and treatment for healthy individuals and those with Achilles tendon injuries. This protocol has been used in many research studies to date and proves valuable in understanding the relationship between tendon structure and injury development, severity, and recovery. As ultrasound devices are becoming more affordable and portable, this protocol proves promising as a clinical tool, given its quick and efficient methods.

Author Spotlight: Exploring the Complexities of Achilles Tendon Injuries &#8212; Research and Future Directions

Ultrasound imaging is becoming more accessible in clinical and research settings, and a consistent protocol will be beneficial for comparison between studies and for clinical interpretations. This protocol for ultrasound evaluation is a valid and reliable method to evaluate Achilles tendon morphology in healthy, tendinopathic, and ruptured tendons.

Achilles tendon injuries occur throughout the lifespan and can negatively affect quality of life and overall health. Achilles tendinopathy is generally ...

Collection of Skeletal Muscle Biopsies from the Superior Compartment of Human Musculus Tibialis Anterior for Mechanical Evaluation

The mechanical properties of contracting skeletal fibers are crucial indicators of overall muscle health, function, and performance. Human skeletal muscle biopsies are often collected for these endeavors. However, relatively few technical descriptions of biopsy procedures, outside of the commonly used musculus vastus lateralis, are available. Although the biopsy techniques are often adjusted to accommodate the characteristics of each muscle under study, few technical reports share these changes to the greater community. Thus, muscle tissue from human participants is often wasted as the operator reinvents the wheel. Expanding the available material on biopsies from a variety of muscles can reduce the incident of failed biopsies. This technical report describes a variation of the modified Bergstr&#246;m technique on the musculus tibialis anterior that limits fiber damage and provides fiber lengths adequate for mechanical evaluation. The surgery is an outpatient procedure that can be completed in an hour. The recovery period for this procedure is immediate for light activity (i.e., walking), up to three days for the resumption of normal physical activity, and about one week for wound care. The extracted tissue can be used for mechanical force experiments and here we present representative activation data. This protocol is appropriate for most collection purposes, potentially adaptable to other skeletal muscles, and may be improved by modifications to the collection needle.

This technical report describes a variation of the modified Bergstr&#246;m technique for the biopsy of the musculus tibialis anterior that limits fiber damage.

The mechanical properties of contracting skeletal fibers are crucial indicators of overall muscle health, function, and performance. Human skeletal muscle ...

Motor Exam I

Source:Tracey A. Milligan, MD; Tamara B. Kaplan, MD; Neurology, Brigham and Women&#39;s/Massachusetts General Hospital, Boston, Massachusetts, USA
Abnormalities in the motor function are associated with a wide range of diseases, from movement disorders and myopathies to strokes. The motor assessment starts with observation of the patient. When the patient enters the examination area, the clinician observes the patient&#39;s ability to walk unassisted and the speed and coordination while moving. Taking the patient&#39;s history provides an additional opportunity to observe for evidence of tremors or other abnormal movements, such as chorea or tardive dyskinesia. Such simple but important observations can yield valuable clues to the diagnosis and help to focus the rest of the examination. The motor assessment continues in a systematic fashion, including inspection for muscle atrophy and abnormal movements, assessment of muscle tone, muscle strength testing, and finally the examination of the muscle reflexes and coordination. The careful systematic testing of the motor system and the integration of all the findings provide insight to the level at which the motor pathway is affected, and also help the clinician to formulate the differential diagnosis and determine the course of the subsequent evaluation and treatment.

Motor Exam I: Evaluation of Muscle Tone and Strength

Source:Tracey A. Milligan, MD; Tamara B. Kaplan, MD; Neurology, Brigham and Women&#39;s/Massachusetts General Hospital, Boston, Massachusetts, USA
...

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Physical Examinations III

Hip Exam

Source: <a href="https://www.jove.com/author/Robert+E._Sallis">Robert E. Sallis</a>, MD. Kaiser Permanente, Fontana, California, USA
The hip is a ball-and-socket joint that consists of the femoral head articulating with the acetabulum. When combined with the hip ligaments, the hip makes for a very strong and stable joint. But, despite this stability, the hip has considerable motion and is prone to degeneration with wear and tear over time and after injury. Hip pain can affect patients of all ages and can be associated with various intra- and extra-articular pathologies. Anatomic location of pain in the hip region can often provide initial diagnostic clues. Essential aspects of the hip exam include an inspection for asymmetry, swelling, and gait abnormalities; palpation for areas of tenderness; range of motion and strength testing; a neurological (sensory) exam; and additional special diagnostic maneuvers to narrow down the differential diagnosis.

Hip Exam: Trendelenburg, Hop, Leg Roll, Ober and FABER Tests

Source: Robert E. Sallis, MD. Kaiser Permanente, Fontana, California, USA
The hip is a ball-and-socket joint that consists of the femoral head ...

Knee Exam

Source: <a href="https://www.jove.com/author/Robert+E._Sallis">Robert E. Sallis</a>, MD. Kaiser Permanente, Fontana, California, USA
The knee is a hinged joint that connects the femur with the tibia. It is the largest joint in the body, and due to its location in the middle of the lower leg, it is subjected to a variety of traumatic and degenerative forces. Examination of the knee can be quite complex, owing to the fact it is an inherently unstable joint held together by various ligaments and supported by menisci, which act as shock absorbers and increase the contact area of the joint. In addition, the patella lies in front of the knee, acting as a fulcrum to allow the forceful extension of the knee needed for running and kicking. As the largest sesamoid bone in the body, the knee is a common source of pain related to trauma or overuse.
When examining the knee, it is important to remove enough clothing so that the entire thigh, knee, and lower leg are exposed. The exam begins with inspection and palpation of key anatomic landmarks, followed by an assessment of the patient's range of motion (ROM). The knee exam continues with tests for ligament or meniscus injury and special testing for patellofemoral dysfunction and dislocation of the patella. The opposite knee should be used as the standard to evaluate the injured knee, provided it has not been previously injured.

Knee Exam: Ligament, Meniscal and Patella Tests

Source: Robert E. Sallis, MD. Kaiser Permanente, Fontana, California, USA
The knee is a hinged joint that connects the femur with the tibia. It is the ...

Ankle Exam

Source: <a href="https://www.jove.com/author/Robert+E._Sallis">Robert E. Sallis</a>, MD. Kaiser Permanente, Fontana, California, USA
The ankle and foot provide the foundation for the body and the stability needed for upright posture and ambulation. Because of its weight-bearing function, the ankle joint is a common site of injury among athletes and in the general population. Ankle injuries occur as a result of both acute trauma and repetitive overuse (such as running). The ankle is a fairly simple joint, consisting of the articulation between the distal tibia and talus of the foot, along with the fibula on the lateral side. The ankle is supported by numerous ligaments, most notably the deltoid ligament on the medial side, and laterally by three lateral ligaments: the anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL). 
Physical examination of the ankle and the patient history (including the mechanism of the injury and the location of pain) provide diagnostic information that helps the physician to pinpoint specific structures involved in an injury, and are essential for determining the severity of the injury and the subsequent diagnostic steps. When examining the ankle, it is important to closely compare the injured ankle to the uninvolved side. Essential components of the ankle exam include inspection, palpation, range of motion (ROM), and strength. In addition, special tests can assess the integrity of ligaments.

Ankle Exam: Talar tilt, Anterior drawer, Squeeze, Thompson Tests

Source: Robert E. Sallis, MD. Kaiser Permanente, Fontana, California, USA
The ankle and foot provide the foundation for the body and the stability needed ...

Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination

Summary

Explore More Videos

Manual Muscle Testing: A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients

Assessment of Neuromuscular Function Using Percutaneous Electrical Nerve Stimulation

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations

Evaluation of Muscle Function of the Extensor Digitorum Longus Muscle Ex vivo and Tibialis Anterior Muscle In situ in Mice

Measurement of Healthy and Injured Triceps Surae Morphology

Collection of Skeletal Muscle Biopsies from the Superior Compartment of Human Musculus Tibialis Anterior for Mechanical Evaluation

Motor Exam I

Hip Exam

Knee Exam

Ankle Exam