BONES AND JOINTS OF THE LOWER LIMBS

Yasser Moh. Aneis, PhD, MSc., PT. Lecturer of Physical Therapy Basic Sciences Department

BONES AND JOINTS OF THE LOWER LIMBS The Pelvis The top portion of the femur with its head in the acetabulum Bones of the right thigh, anterior and posterior view Bones of the lower leg Bones of the foot PELVIC ELEVATION (Hip Hiking) oThe Primary muscle •Quadratus Lumborum

Origin: -Iliac crest. -Iliolumber ligament. Insertion: -Inferior border of 12th rib. -Apices of transverse processes of L1- 4. - Iliolumber ligament. Nerve supply: -Anterior primary rami (T12, L1, L2, L3) Range of Motion: -In standing position pelvis may be raised on one side until foot is well clear of floor. Action: -Elevates the pelvis laterally by producing a lateral flexion of the lumber spine. -Depress the last rib and fixes the last two ribs during forced expiration. Action of Quadratus Lumborum Muscle •Factors Limiting Motion: -Tension of spinal ligaments on opposite side. -Contact of iliac crest with thorax. Testing procedure oGrades 4-5. "Good and Normal strength"

-Back lying with lumbar area of spine in moderate extension. -Patient grasps edge of table to stabilize thorax. -Therapist stands at the foot of the table, both hands grasping the lower limb above or proximal to the ankle joint. •Command: -Pull up your pelvis toward the thorax on one side ----Relax. •Resistance: -resistance is given in a form of traction on the extremity directly opposing the line of pull. oGrade 3 and Grade 2 (Fair and Poor Strength)

-Patient starting position :Same as for Grade 4&5. -Therapist stands at the foot of the table, both hands grasping the lower limb above or proximal to the ankle joint. •Resistance: -Grade 3: Slight resistance is given in a form of traction on the extremity directly opposing the line of pull. -Grade 2:No resistance but complete range of motion. oGrade 3 Fair Strength (Alternative) -Patient Starting Position is Standing. -Therapist stride standing behind the patient stabilizes the patient thorax with both hands. •Command: -pull up your pelvis toward the thorax on one side through full ROM ----Relax. oGrades 1 and 0. "Trace and Zero strength" -The patient is Back lying with leg completely extension. -The therapist stands at the side of the table and support the thigh with his arm (proximal to the knee ) as his proximal hands deeply palpates in the lumber area under lateral edge of erector spine. Muscle Testing of Hip Flexion oThe Primary muscles -Psoas major. -Iliacus. oThe Accessory muscles -Rectus Femoris. -Tensor fasciae late. -Sartorius. -Pectineus. Psoas Major Muscle Origin: -Transverse processes of all lumber vertebrae L1-5. -Bodies and intervertebral disks of the last thoracic and all lumbar vertebraeInsertion: -Middle surface of lesser trochanter of femur. Action: -Flexes and laterally rotates hip Nerve: Anterior primary rami of L1,2,3,4 Iliacus Muscle

Origin: -The inner border of the iliac crest. Insertion: -Lowermost surface of lesser trochanter of femur. Action: -Flexes and laterally rotates hip Nerve: Anterior primary rami of L1,2,3,4. Range of Motion: -The hip flexion with the knee flexed will permit a range of motion approximately 115 to 125. •Factors Limiting Motion:

-Contact of thigh on abdomen. -Tension of the hamstring muscles

Action of Iliopsoas Muscle Testing procedure oGrade 3 "fair strength" -Patient is sitting with legs over edge of table, grasping the edge of table to stabilize pelvis or arms may be folded on the chest if patient is stable enough. -The therapist stand at the foot of the table, with one hand against the anterior shoulder area gives counter pressure. -while the other hand applies pressure against the thigh, in the direction of hip extension. •Command: -Raise up your leg vertically “in the mid line” towards your chest through full range of motion then-relax. oGrades 4-5. "Good and Normal strength" -Same as for Grade 3. with one hand against the anterior shoulder area gives counter pressure, while the other hand applies pressure against the thigh, in the direction of hip extension. -Grade 4: Moderate leading resistance is given directly opposing the line of motion. -Grade 5: Maximum leading resistance is given throughout the range plus a "hold" at the end of the range. oGrade 2. "poor strength"

•Patient Starting Position is Side lying, -with the affected leg down. -Trunk, pelvis, legs are straight. -Upper leg is supported. •Therapist stands behind the patient with the proximal hand stabilizing the pelvis “the side of the affected leg and the distal hand supporting the upper leg. •Note: Patient is allowed to flex the knee to prevent tension brought by the hamstring muscles. •Command: -With flexed knee move your leg toward your chest through full range of motion.----relax. oGrades 1 and 0. "Trace and Zero strength" -The patient is Back lying, both legs are extended, with affected leg near the edge of the table. -Therapist stands beside the table, distal hand supporting the affected leg, the proximal hand palpating contraction of psoas major muscle just distal to the inguinal ligament. Substitutions -Substitution by Sartorius in hip flexion causes lateral rotation and abduction of thigh.

Hip Flexion, Abduction & External Rotation by Sartorius Muscle -Substitution by tensor fasciae latae in hip flexion causes medial rotation and abduction of thigh.

Hip Flexion, Abduction & internal Rotation by tensor fasciae latae Muscle Effects of weakness of the hip flexor muscles •Weakness of the hip flexor muscles decreases the ability to flex the hip joint and results in marked disability in: -Stair climbing. -Walking up or down the incline. -Getting up from a reclined position. -Bringing the trunk forward in the sitting position preliminary to rising from a chair. •In marked weakness, walking is difficult because the leg must be brought forward by pelvic motion (produced by anterior or lateral abdominal muscle action) rather than by hip flexion. Contracture of Hip Flexor Muscles, and Their Effect on Posture

-Bilateral hip flexion deformity will be combined with increased lumber lordosis.

Iliopsoas Muscle Bilateral Hip Flexion Compensatory Kypho-Lordosis -Unilateral hip flexion contracture will be often combined with hip abduction and external rotation.

Muscle Testing of Hip Extension oThe Primary muscles

-Gluteus Maximus -Biceps Femoris -Semimembranosus -Semitendinosus Gluteus Maximus Muscle Origin -Outer surface of ilium behind posterior gluteal line -posterior third of iliac crest -lumbar fascia -lateral mass of sacrum & coccyx Insertion -Gluteal tuberosity of femur -Iliotibial tract Nerve supply -Inferior gluteal nerve (L5, S1,2) Action -Extends and laterally rotates hip. -Maintains knee extended via iliotibial tract Biceps Femoris Origin -Long head: posterior surface of ischial tuberosity -Short head: middle third of linea aspera, lateral supracondylar ridge of femur Insertion -Head of fibula -Lateral collateral ligament -Lateral tibial condyle Nerve supply -Sciatic nerve Action -Flexes and laterally rotates knee -Long head extends hip Semimembranosus Origin -Posterior surface of ischial tuberosity Insertion -Medial condyle of tibia below articular margin Nerve supply -Sciatic nerve (L5, S1) Action -Extends hip -Flexes and medially rotates knee Semitendinosus Origin -Posterior surface of ischial tuberosity Insertion -Upper medial shaft of tibia Nerve supply -Sciatic nerve (L5, S1) Action -Extends hip -Flexes and medially rotates knee Range of Motion: -Extension: 115º – 125º to 0º. -Extension beyond midline 0º to 10º - 15º. •Factors Limiting Motion: -Tension of iliofemoral ligament. -Tension of hip flexor muscles Testing procedure oGrade 3 "fair strength" -Patient Starting Position is Prone lying with legs extended. -Therapist stands beside the table with the proximal hand stabilizing the pelvis. •Command: -Raise up your leg through full range of motion---- relax oGrades 4-5. "Good and Normal strength" -Same as for Grade 3. with one hand stabilizing the pelvis. While the distal hand is placed proximal to the knee joint to give resistance. Resistance -Resistance is given in a form of pressing down directly opposing the line of raising. oGrade 2. "poor strength"

-The patient is side lying with affected legs on the table, hip flexed, and knee extended.

-Therapist stands behind the patient with the proximal hand stabilizing the pelvis & the distal hand supporting the uppermost leg. oGrades 1 and 0. "Trace and Zero strength" -Patient Starting Position is prone lying with legs extended. -Therapist stands behind the patient with his hands palpates the upper and lower portion of the muscles. -A contraction of the gluteus maximus muscle will result in a narrowing of the gluteal crease. -Command: Squeeze or press your buttock together --- -- relax. Test for isolation of Gluteus Maximus Muscle

-Patient Starting position is prone with knee flexed. -The therapist proximal hand stabilizing the pelvis -The distal hand is placed proximal to the knee joint to give resistance. •Command: -Extends your hip, keeping knee flexed to decrease action of hamstrings. Effects of weakness of the hip extensor muscles -Bilateral marked weakness of the Gluteus maximus muscle makes walking extremely difficult, and necessitates the aid of crutches. -Raising the trunk from a forward-bent position requires action of the gluteus maximus, and in cases of weakness, patients must push themselves to an upright position using their arms. -when gluteus maximus is weak, trunk lurches backward (maximus lurch) at heel-strike on weakened side to interrupt forward motion of trunk (Lurching Gait) Muscle Testing of Hip Abduction Hip Abductors oThe Primary muscles -Gluteus Medius -Gluteus Minimus oThe Accessory muscles -Tensor Fasciae Latae -Gluteus Maximus (upper fibers) Gluteus Medius Origin -External surface of the ilium -Gluteal Aponeurosis Insertion -lateral surface of the greater trochanter of the femur Nerve supply -Superior gluteal, L4, 5, SI. Action: Abducts the hip joint. -The anterior fibers medially rotate and may assist in flexion of the hip joint. -The posterior fibers laterally rotate and may assist in extension.

Gluteus Medius Muscle Gluteus Minimus Origin -External surface of the ilium -Margin of the greater sciatic notch Insertion -Anterior border of the greater trochanter of the femur and hip joint capsule Nerve supply -Superior gluteal, L4, 5, SI. Action: Abducts, medially rotates and may assist in flexion of the hip joint. Gluteus Minimus Muscle -Along with the gluteus medius muscle, the gluteus minimus assists in abducting, or lifting, the thigh outwards. -They play an important part in keeping the torso upright when the foot of the opposite side is off the ground during walking and running.

-Both muscles work to keep the body erect when you stand with one foot raised. oRange of Motion: -From the mid line to full range of motion, the hip joint can abduct for 45º .

•Factors Limiting Motion: -Tension of hip adductor muscles -Tension of distal band of iliofemoral ligament -Tension of pubocapsular ligament Testing procedure oGrade 3 "fair strength" -Patient is Side lying affected leg is upper, slightly extended beyond mid line ,lower knee flexed for balance. -The therapist stands behind the patient, proximal hand stabilizing pelvis. •Command -Raise up your leg through full range of motion without lateral rotation of the hip ------Relax. oGrades 4-5. "Good and Normal strength" -The same as for grade 3 with the therapist’s proximal hand stabilizing pelvis plus the distal hand is placed proximal to knee joint to give resistance. Resistance -Resistance is given in a form of pressing down directly opposing the line of raising Grades 4 -Moderate leading resistance is given directly opposing the line of motion -Grade 5: Maximum leading resistance is given throughout the range plus a "hold" at the end of the range.oGrade 2. "poor strength" -Patient Starting Position is Back lying with leg extended the affected leg away from the therapist. -The therapist stands beside the table, proximal hand stabilizing pelvis, the distal hand grasps around the ankle to fix the leg on the table -Command: Move your leg outward through full range of Motion without lateral rotation of the hip ------Relax. oGrades 1 and 0. "Trace and Zero strength" -Patient Starting Position is Back lying with leg extended

-The therapist stands beside the table, the distal hand grasps around the ankle of the affected leg. -The proximal hand is placed on the on lateral aspect of Ilium above greater trochanter of femur to palpate the contraction -Command: Try to move your leg outward through full range of motion without lateral rotation of the hip Substitutions

-Patient may bring pelvis to thorax by strong contraction of lateral trunk muscles, thereby lifting leg through partial abduction

-Lateral rotation at the hip should be eliminated, or hip flexors may substitute for Gluteus medius. Paralysis or Marked Weakness of Gluteus Medius -With paralysis or marked weakness of the gluteus medius, a gluteus medius limp (waddling gait) will occur in walking. -This consists of displacement of the trunk laterally, toward the side of weakness, shifting the center of gravity in such a way that the body can be balanced over the extremity with minimal Paralysis or Marked Weakness muscular support at the hip joint. of Right Gluteus Medius Muscle Testing of Hip Adduction Hip Adductors oThe Primary muscles -Gracilis -Pectineus -Adductor Magnus -Adductor Longus -Adductor Brevis Gracilis Origin -Inferior half of the symphysis pubis -Inferior ramus of the pubic bone Insertion -Medial surface of the body of the tibia Nerve supply -Obturator nerve, L2, 3, 4 Action -Hip adduction, Knee flexion and medial rotation Pectineus

Origin -Surface of the superior pubic ramus Insertion -Pectineal line of the femur Nerve supply -Femoral and Obturator, L2, 3, 4. Action -Hip Adduction -Assist in Hip flexion Adductor Magnus

Origin -Inferior pubic ramus -Ramus of the ischium -Ischial tuberosity Insertion -Gluteal Tuberosity -Middle of the linea aspera -Medial Supracondylar Line -Adductor Tubercle Nerve supply -Obturator, L2, 3, 4, and Sciatic, L4, 5, SI. Action -Hip Adduction -Assist in Hip internal Rotation Adductor Longus Origin -Anterior surface of the pubis Insertion -Middle 1/3 of the medial lip of the linea aspera Nerve supply -Obturator Nerve, L2, 3, 4. Action: Hip Adduction Adductor Brevis

Origin -Outer surface of the inferior pubic ramus Insertion -Distal 2/3 of the pectineal line -Proximal half of the medial lip of the linea aspera Nerve supply -Obturator nerve, L2, 3, 4 Action: Hip Adduction oRange of Motion: -From the hip abduction position to the mid line the range of motion is 450 .

•Factors Limiting Motion: -Tension of hip abductor muscles -Contact with opposite leg -Tension of ischio-femoral ligament Testing procedure oGrade 3 "fair strength" -Patient is side lying with the ” affected leg down” while the upper leg supported in approximately 25º of abduction.

-The therapist stands behind the patient, supporting the patient’s upper leg. -Command: Raise up your leg up ward until it contacts upper one ------Relax oGrades 4-5. "Good and Normal strength" -The same as for grade 3 with the therapist’s distal hand supporting the upper leg, while the proximal hand is placed proximal to knee joint to give resistance. -Resistance: Resistance is given in a form of pressing down directly opposing the line of raising -Grades 4: Moderate leading resistance is given directly opposing the line of motion -Grade 5: Maximum leading resistance is given throughout the range plus a "hold" at the end of the range. oGrade 2. "poor strength" -Patient Starting Position is Back lying with leg extended the affected leg away from the therapist (abducted in 45º) . -The therapist stands beside the table, proximal hand stabilizing pelvis, the distal hand grasps around the ankle to fix the leg on the table -Command: Move your leg towards the other without rotation of hip----relax. oGrades 1 and 0. "Trace and Zero strength"

-Patient Starting Position is Back lying with leg extended the affected leg away from the therapist (abducted in 45º) . -The therapist stands beside the table, The distal hand grasps around the ankle of the affected leg, the proximal hand palpates the contraction of fibers of muscles on medial aspect of thigh. -Command:Try to move your leg towards the other without rotation of hip----relax. Substitutions

-Forward rotation of the pelvis with extension of the hip joint shows an attempt to hold with the lower fibers of the gluteus maximus.

-Anterior tilting of the pelvis, or flexion of the hip joint (with backward rotation of the pelvis on upper side), allows substitution by the hip flexors. Adductor Contracture

-Hip adduction deformity -In standing, the position is one of lateral pelvic tilt, with the pelvis so high on the side of contracture that it becomes necessary to plantar flex the foot on the same side, holding it in equinus so the toes can touch the floor. -As an alternative, if the foot is placed flat on the floor, the opposite extremity must be either flexed at the hip and knee or abducted to compensate for the apparent shortness on the adducted side. Adductor Contracture Muscle Testing of Hip External Rotation Hip External Rotators oThe Primary muscles -Obturator Internus -Obturator Externus -Gemellus Superior -Gemellus Inferior -Quadratus Femoris -Piriformis Obturator Internus Origin -Pelvic surface of the obturator membrane -Margin of the obturator foramen. -Pelvic surface of the ischium -Obturator fascia Insertion -Medial surface of the greater trochanter Nerve supply -Sacral plexus, L5, SI. 2. Action: Laterally rotate the hip joint & assist in hip abduction when it is flexed. Obturator Externus Origin -Rami of the pubis and ischium -External surface of the obturator membrane Insertion -Trochanteric fossa of the femur Nerve supply -Obturator, L3, 4. Action -Laterally rotate the hip joint & assist in its adduction. Gemellus Superior

Origin -External surface of the spine of the ischium Insertion -Medial surface of the greater trochanter with the tendon of the obturator internus Nerve supply -Sacral plexus, L5, SI, 2. Action: Laterally rotate the hip joint & assist in hip abduction when it is flexed. Gemellus Inferior

Origin -Proximal part of the tuberosity of the ischium Insertion -Medial surface of the greater trochanter with the tendon of the obturator internus Nerve supply -Sacral plexus, L4, 5, SI, 2 Action: Laterally rotate the hip joint & assist in hip abduction when it is flexed. Quadratus Femoris

Origin -Lateral border of the tuberosity of the ischium Insertion -Quadrate line, extending distally from the intertrochanteric crest. Nerve supply -Sacral plexus, L4, 5, SI, 2 Action -Laterally rotate the hip joint Piriformis

Origin -Pelvic surface of the sacrum between the first through fourth pelvic sacral foramina -Margin of the greater sciatic foramen Insertion -Superior border of the greater trochanter of the femur Nerve supply: Sacral plexus, L5, SI, 2 Action: Laterally rotate the hip joint & assist in its extension. oRange of Motion: -With the knee in flexion the hip lateral rotation is of 45° of motion. -With the knee in extension the range of motion will have tendency to be of less amplitude.

•Factors Limiting Motion: -Tension of hip medial rotator muscles. -Tension of lateral band of iliofemoral ligament Testing procedure oGrade 3 "fair strength" -Patient is sitting with legs over edge of table. Patient grasps edge of the examining table to stabilize the pelvis. -The therapist stands in front of the patient on the side of affected leg. -The proximal hand applies a counter pressure above the knee joint to prevent abduction and flexion of the Command:hip. Bring your foot over the other leg keeping your thigh in contact with the table---- Relax. oGrades 4-5. "Good and Normal strength"

-Same as for grade 3 with the therapist’s distal hand is placed on the medial surface of the leg just above the ankle joint to give resistance. -Resistance: Resistance is given in a form of pressing down & laterally directly opposing the line of raising. -Grades 4: Moderate leading resistance is given directly opposing the line of motion -Grade 5: Maximum leading resistance is given throughout the range plus a "hold" at the end of the range. oGrade 2. "poor strength" -Patient is back lying, the affected leg is in medial rotation, away from the therapist. -The therapist standing beside the table at the level of the patient thigh. The proximal hand is placed on the anterior superior iliac spine to stabilize the pelvis. -Command: Turn your leg outward through full range of motion-----Relax. oGrades 1 and 0. "Trace and Zero strength"

-Patient is back lying, the affected leg is in medial rotation, away from the therapist. -Therapist standing beside the table at the level of the patient thigh. -The proximal hand is palpating deeply for muscle contraction behind the greater trochanter. Weakness of Hip Lateral Rotators

-Usually Weakness of the lateral rotators of the hip will produce a medial rotation of the femur accompanied by pronation of the foot and a tendency toward a knock- knee (or valgus) position. Contracture of the Lateral Rotators of the Hip

-Contracture of the Lateral rotators of the hip is usually occurring in an abducted position of the hip.

-The range of medial rotation of the hip will be limited and in the standing posture, a lateral rotation of the femur and out-toeing are observed. Piriformis Syndrome

-Piriformis syndrome: is a neuromuscular disorder that occurs when the sciatic nerve is compressed or otherwise irritated by the piriformis muscle.

-causing pain, tingling and numbness in the buttocks and along the path of the sciatic nerve descending down the lower thigh and into the leg. -Pathophysiology: While the piriformis muscle shortens or spasms due to trauma or overuse, it can compress the sciatic nerve beneath the muscle. -Generally, conditions of this type are referred to as nerve entrapment or as entrapment neuropathies -Management •Rest - Avoid activities that cause the symptoms. •Stretching and Strengthening the hip Rotators. Deep Friction Massage. •Anti-Inflammatory Medication. Piriformis Muscle Stretch Muscle Testing of Hip Internal Rotation Hip Internal Rotators oThe Primary muscles -Glutaei Medius -Gluteus Minimus -Tensor Fasciae Latae oThe Accessory muscles -Superior Portion of the Adductor Magnus -Adductors Longus -Adductors Brevis -Semitendinosus -Semimembranosus Gluteus Medius Origin -External surface of the ilium -Gluteal Aponeurosis Insertion -lateral surface of the greater trochanter of the femur Nerve supply -Superior gluteal, L4, 5, SI. Action: Abducts the hip joint. -The anterior fibers medially rotate and may assist in flexion of the hip joint. -The posterior fibers laterally rotate and may assist in extension.

Gluteus Medius Muscle Gluteus Minimus Origin -External surface of the ilium -Margin of the greater sciatic notch Insertion -Anterior border of the greater trochanter of the femur and hip joint capsule Nerve supply -Superior gluteal, L4, 5, SI. Action: Abducts, medially rotates and may assist in flexion of the hip joint. Gluteus Minimus Muscle Tensor Fasciae Latae Origin -Anterior part of the external lip of the iliac crest -Outer surface of the anterosuperior iliac spine Insertion -Into a large band of tendon called the iliotibial tract or the facsiae latae. Nerve supply -Superior Gluteal, L4, 5, SI. Action: Flexes, medially rotates, and abducts the hip joint. Tenses the fascia lata. May assist in knee extension. oRange of Motion: -The medial rotation of the hip with the knee flexed is of 0-45° (less with hip extended).

•Factors Limiting Motion: -Tension of hip lateral rotator muscles -Tension of iliofemoral ligament, When hip is extended -Tension of ischiocapsular ligament, When hip is flexed Testing procedure oGrade 3 "fair strength" -Patient is sitting with legs over edge of table. Patient grasps edge of the examining table to stabilize the pelvis. -The therapist stands in front of the patient on the side of affected leg. -The proximal hand applies a counter pressure above the knee joint to prevent adduction and flexion of the Command:hip. Bring your foot away from the other leg keeping your thigh in contact with the table---- Relax. oGrades 4-5. "Good and Normal strength"

-Same as for grade 3 with the therapist’s distal hand is placed on the lateral surface of the leg just above the ankle joint to give resistance. -Resistance: Resistance is given in a form of pressing down & medially directly opposing the line of raising. -Grades 4: Moderate leading resistance is given directly opposing the line of motion -Grade 5: Maximum leading resistance is given throughout the range plus a "hold" at the end of the range. oGrade 2. "poor strength"

-Patient is back lying, the affected leg is in lateral rotation, away from the therapist. -The therapist standing beside the table at the level of the patient thigh. The proximal hand is placed on the anterior superior iliac spine to stabilize the pelvis.

-Command: Turn your leg inward through full range of motion-----Relax. oGrades 1 and 0. "Trace and Zero strength" -Patient is back lying, the affected leg is in lateral rotation, away from the therapist. -Therapist standing beside the table at the level of the patient thigh. -Therapist is Standing beside the table, the proximal hand palpates the contraction of Tensor fasciae Latae near its origin posterior and distal to anterior superior spine of ilium. -Glutens Minimus fibers lie beneath Gluteus medius and Tensor fasciae Latae stabilizing the pelvis. the distal hand grasps around the ankle. Weakness of Hip Medial Rotators

-Weakness of the hip medial rotation of the femur is accompanied by Lateral rotation of the thigh, usually in an abducted position. Contracture of the Medial Rotators of the Hip

-Accompanied by pronation of the foot and a tendency toward a knock- knee (or valgus) position. -Shortness: Inability to laterally rotate the thigh through the full range of motion, and inability to sit in a cross legged position (i.e., tailor fashion). Trendelenburg Sign and Hip Abductor Weakness

-Along with the gluteus medius muscle, the gluteus minimus assists in abducting, or lifting, the thigh -outwards.They play an important part in keeping the torso upright when the foot of the opposite side is off the ground during walking and running. -strong hip abductors can stabilize the pelvis on the femur in hip joint abduction, as shown in Figure A. -Figure B shows a position of hip joint adduction that results when hip abductors are too weak to stabilize the pelvis on the femur. The pelvis drops downward on the opposite side.

-Figure B indicates a positive Trendelenburg Sign On the right side i.e. Weak right gluteus medius muscle. -Figure A indicates a negative Trendelenburg Sign On the right side i.e. Strong right gluteus medius muscle. -With paralysis or marked weakness of the gluteus medius, a gluteus medius limp (waddling gait) will occur in walking.