Ch. 6 & 8 Quiz Flashcards
Functions of Pelvic Girdle
- Supports body weight, improves LE ROM, attachment site for 28 trunk/thigh muscles, placement is key for efficient joint mechanics, transfer of force from LE to trunk, balance, posture, birth, equilibrium
Structure of Pelvic Girdle
- Sacrum: posterior/base of pelvic
- Ilium: superior
- Ischium: posterorinferior
- Pubis: anteroinferior
- Vary between males and females
- Fuse between 20-25yr
Major Joints of pelvic and hip complex
- Pubic symphysis
- Sacro-iliac joint (SI)
- Lumbosacral Joint
Sacroiliac Joint
- Strong, stable joint with some movement
- Men have less movement due to thicker ligament (3/10 male SI joints are fused)
- Females have more laxity in SIJ (changes during menstrual cycle, large increase during pregnancy)
- Movement (regarding apex) - sacral flexion - nutation, sacral extension - counternutation
Movement of the pelvic and hip complex
- Movements of the pelvis are described by monitoring the ilium
- kicking a soccer ball
-long ump - jumping to catch a ball
-sprint
Pelvis + Thigh
- In a closed chain weight bearing movement, the pelvis moves about a fixed femur
- In an open chain position such as hanging, the femur moves on the pelvis
- Pelvic girdle rotates to the left and right as unilateral leg movement takes place
Hip Joint
- Ball and Socket Joint - flexion is greatest ROM
-Articulation: Acetabulum - where 3 bones of the pelvis make their fibrous connections - surrounding the whole hip joint is a loose but strong capsule
- hip is one of the most stable joints in the body because of the powerful muscles, shape of the bones, the labrum and the strong capsule and ligaments
Angle of Inclination
- The angle of the femoral neck with respect to the shaft of the femur in the frontal plane, this determines the effectiveness of the hip abductors, the length of the limb, and the forces imposed on the hip joint
- angle approx 125 degrees
Angle of Anteversion
- The angle of the femoral neck in the transverse plane
- Normally, the femoral neck is rotated anteriorly 12° to 14° with respect to the femur
- Increases the mechanical advantage of the gluteus maximus
- Excessive anteversion include an increase in the Q-angle, patellar problems, long legs, more pronation at the subtalar joint, and an increase in lumbar curvature
How are lower extremities (LE) and trunk connected?
- The pelvic girdle
How does LE accept forces and what does it support?
- Accepts forces via repetitive contacts between the foot and the ground
- it is responsible for supporting the mass of the trunk and upper extremities
Pelvic Femoral Rhythm
- the coordinated movement between the pelvis and the hip joint
Hip Movements
- Flexion - limited primarily by the soft tissue
- Extension - limited by the anterior capsule, the strong hip flexors, and the iliofemoral ligament
- Abduction - limited by the adductor muscles
- Adduction - limited by the tensor fascia latae muscle
- Internal and External Rotation - limited by their antagonistic muscle group and the ligaments of the hip joint
Hip Strength
- The hip muscle generate the greatest strength output in extension - gluteus Maximus, combines with the hamstrings
- Hip flexion strength is primarily generated with the iliopsoas muscle
- The potential for the development of adduction strength is substantial because the muscles contributing to the movement are massive as a group and adductors can develop more force output than the abductors(think muscle mass balance)
- The strength of the external rotators is 60% greater than that of the internal rotators except in hip flexion, when the internal rotators are slightly stronger
Conditioning the Hip
- Walking, rising from or lowering into a chair, ADLs
- Best to design exercises using a closed kinetic chain, in this type of activity the foot or feet are in contact with a surface (ground) and forces are applied to the system at the feet
Sacroiliitis
- With excessive mobility, large forces are transferred to the sacroiliac joint, producing an inflammation of the joint
- The sacroiliac joint also becomes very mobile in pregnant women, making them more susceptible to sacroiliac sprain
Pelvic Ring Fracture
- Traumatic injury to the pelvic girdle
- Occurs in high level trauma such as motor vehicle accidents, falls from height or a crushing injury
Legg-Calve- Perthes Disease
- In children 3 to 12 years old
- the femoral head degenerates, and the proximal femoral epiphysis is damages
Slipped Capital Femoral Epiphysitis
- Caused by some traumatic event that forces the femoral neck into external rotation, or it can be caused by failure of the cartilaginous growth plates
Congenital Hip Dislocation
- A disorder that affects girls more often than boys
Osteoarthritis
- An age-related disorder of the hip joint seen commonly in elderly individuals
Muscle Strains, Tendinitis or the muscle insertion or Bursitis
- More than 60% of injuries to the hip occur in the soft tissue [101]. Of these injuries, 62% occur in running, 62% are associated with a varum alignment in the lower extremity, and 30% are associated with a leg length discrepancy
Iliotibial Band syndrome and snapping hip syndrome
- 2 remaining soft-tissue injuries seen in dancers and distance runners are lateral hip pain causes by these
Knee Joint
- supports the weight of the body
- transmits forces from the ground while
- allowing a great deal of movement between the femur and the tibia
Position of the Knee Joint
- Extended: the knee joint is stable because of its vertical alignment, the congruency of the joint surfaces, and the effect of gravity.
- Flexed: the knee joint is mobile and requires special stabilization from the powerful capsule, ligaments, and muscles surrounding the joint. The joint is vulnerable to injury because of the mechanical demands on it and the reliance on soft tissue for support.
Knee Joint Ligaments
- Support the joint passively as they are loaded in tension only
Knee Joint Muscles
- Support the joint actively and are also loaded in tension
Knee Joint Bones
Support and resistance to compressive loads
Tibiofemoral Joint (of knee)
- The actual knee joint
- Primary movement - flexion/extension, plus flexion with small, but significant flexion
- 2 fibrocartilage menisci lie btw the tibia and the femur, enhance lubrication of the joint
- Supported by 4 main ligaments, 2 collateral and 2 cruciate
Medial Collateral Ligament (MCL)
- Supports the knee against any valgus force
Lateral Collateral Ligament
- Supports the knee against any varus force
Cruciate Ligaments
- are intrinsic, lying inside the joint in the intercondylar space
ACL
- Provides the primary restraint for anterior movement of the tibia relative to the femur
PCL
- Offers the primary restraint to posterior movement of the tibia on the femur
Patellofemoral Joint
- Consisting of the articulation of the patella with the trochlear groove on the femur
- Primary role: increase the mechanical advantage of the quadriceps femoris
- The patella is connected to the tibial tuberosity via the strong patellar ligament
Q-Angle
- Line from ASIS —> mid patella
- Line from tibial tuberosity —> through mid patella
- Male - btw 10° to 14°
- Female - btw 15° to 17° due to wider pelvic basins
- 17° = genu valgum, or knock knees
- very small/negative = genu varum or bow-leggedness
Tibiofibular Joint
- Articulation between the head of the fibula and the posterolateral and inferior aspect of the tibial condyle.
- Movement: gliding joint from A-P, superiorly, and inferiorly and rotating
- Primary function: dissipate the torsional/rotational*** stresses applied by the movements of the foot and to attenuate lateral tibial bending.
Movement of the Knee
- Complex because: asymmetries and patellar involvement
- Weight bearing(closed chain) + flexion = femur rolls back onto tibia(more stable)
- Open chain + flexion = anterior tibial motion
Knee Strength
- Extensors > flexors in most ROM
Knee Injuries
- The knee joint is a frequently injured area of the body, depending on the sport, accounting for 25% to 70% of reported injuries.
- The cause of an injury to the knee can often be related to poor conditioning or training or to an alignment problem in the lower extremity
- Traumatic injuries to the knee usually involve the ligaments, typically from a twisting mechanism
Damage to the Menisci
- The menisci can be torn through compression associated with a twisting action in a weight-bearing position. They can also be torn in kicking and other violent extension actions.
Patellofemoral Pain Syndrome
- is pain around the patella and is often seen in individuals who exhibit valgum alignments or femoral anteversion in the extremity
Chondromalacia Patellae
- Some patellofemoral pain syndromes are associated with cartilage destruction, in which the cartilage underneath the patella becomes soft and fibrillated
Osgood-Schlatter Disease
- in children 8 to 15 years old, a tibial epiphysitis can develop, is an allusion fracture of the growing tibial tuberosity
Structure of Ankle and Foot
- 26 bones
- 30 synovial joints
- 100 ligaments
- 30 muscles
- Three main joints: the talocrural, the subtalar, and the midtarsal joints
- foot moves in 3 planes, with most of the motion occurring in the rear foot
- 3 regions rear/hind foot, midfoot, and forefoot
Functions of Ankle and Foot
- Supports BW in standing and locomotion
- Adapt to ground contact
- Shock absorber
- Lever in propulsion
- In stance, absorb rotation in LE
Ligaments of Ankle and Foot
- No muscles attach to the talus
- the lateral side of the ankle joint is more susceptible to injury, accounting for 85% of ankle sprains
- Ligaments damaged by an inversion ankle sprain - ligaments, bones, muscles and nerves
Talocrural
- Proximal Joint
- Uniaxial Hinge
- Tibiofibular joint + tibiotalar joint
- Stability***
- Major stabilizers are the ligament structures
Subtalar/ Talocalcaneal
- Distal from Talocrural
- The prime function of the subtalar joint is to absorb the rotation of the lower extremity during the support phase of gait.
- A second function of the subtalar joint is shock absorption.
Midtarsal Joint
- Greatest functional significance
- It actually consists of two joints - calcaneocuboid joint - lateral side, - talonavicular joint - medial side
- Motion at these two joints contributes to the inversion and eversion, abduction and adduction, and dorsiflexion and plantar flexion at the subtalar and ankle joints.
- Movement depends on the subtalar joint position.
- Subtalar Pronation = mobility
- Subtalar Supination = rigid stability
Arches of the foot
- Creates an elastic shock-absorbing system
- The tarsals and metatarsals of the foot form three arches, two running longitudinally and one running transversely across the foot
Movement of Ankle and Foot
- The range of motion at the ankle joint varies with the application of loads to the joint.
- Movements at the knee and foot need to be coordinated to maximize absorption of forces and
minimize strain in the lower extremity linkage. - Many injuries of the lower extremity are thought to
be associated with a lack of synchrony between these movements at the knee and subtalar joint. - Strongest movement - plantar flexion
Muscles of the Ankle and Foot
- 23 muscles
- 12 originating outside the foot - all of the 12 extrinsic muscles, except for the gastrocnemius, soleus, and plantaris, act across both the subtalar and midtarsal joints
- 11 inside the foot - intrinsic muscles of the foot are usually atrophied and weak because we regularly wear shoes
Injuries of Ankle and Foot
- Common place for LE injury
- most injuries benefit from therapeutic exercise programs
- One of the most common injuries to the foot is ankle sprain. Sprains most commonly occur in the lateral complex of the ankle during inversion
Posterior or medial tibial syndrome
- previously referred to as shin splints, generates pain above the medial malleolus
Plantar Fasciitis
- an inflammation of the plantar fascia on the underside of the foot, is another common soft-tissue injury to the foot
Anterior Compartment Syndrome
- is a case in which nerve and vascular compression occur as a result of hypertrophy in the anterior tibial muscles, the most affected compartment in the lower leg
Forces acting on Hip Joint
- the hip joint can withstand 12 to 15 times BW before fracture or breakdown in the osseous component occurs
Forces acting on Ankle and foot joints
- Large loads on the talus must be expected because it is the keystone of the foot
Tissue Injury
- Injury to tissue involves a transfer of energy in which the mechanical load exceeds the tolerance level of tissue such as bone, ligament, tendon, or muscle
- Injuries to tissues can be classified as - 1. Traumatic 2. Acute 3. Overuse injury
Acute Injury
- Occurs within a traumatic, SINGULAR event
- fall, impact, blunt force, twist
- signs - swelling, pain, tenderness, bruising, restricted ROM
Acute Injury - Muscle
- One of most common injuries in sport/exercise
- most common groups - hamstrings, thigh adductors, quads, calves
- typical - strain (tension) and contusions (compression)
- Strain Categories (based on damage to fibers and magnitude of the loss of function) - mild, moderate, serve
Acute Injury Healing
- First 48 hours: granulocytes —> injured area.
- First few days: Initial inflammatory phase with monocytes/marcophages to clean and remove debris, Followed by vascularization and proliferation
- Next 5 to 7 days: Anti-inflammatory macrophages take over, Angiogenesis is stimulated, and myofiber growth, Muscle regeneration via Cytokines and growth factors
- 3-4 weeks: Repair phase: a connective tissue scar is formed, and this gives the muscle some contraction strength to avoid re-injury.
- 3-6 months: Final remodeling phase: new formed myofibrils mature, and the scar tissue hopefully contracts.
Acute Injury Bone
- Typically occurs in a traumatic event where forces overcome the tolerance level of bone tissue and results in a fracture
- By falls and accidents
- When a bone is fractured, the healing process is similar to how the skeleton is formed. Bone Injury modeling: Resorption by osteoclasts —> new bone is formed by osteoblasts.
Acute Injury - Bone Healing
- The bone repair process follows a similar pattern to that of the muscle***.
- Initial: a hematoma is formed, A build up of platelets and angiogenesis, macrophage facilitation of regeneration
- Proliferative phase: at hematoma, Necrotic bone resorption, Callus formation begins
- Final remodeling phase: replacement of the callus with mineralized bone.
What’s a key factor in the difference in healing btw muscle and bone?
- Bone healing takes longer, but injury site will typically be VERY strong
- muscles have more blood flow then bones which is why muscles heal faster
Acute Injury - Tendon and Ligaments
- Common injuries
- Natural healing process is slow because - 1. Deficit of blood vessels, 2. Hypocellular nature
- similar healing process
Overuse Injury
- Caused by repetitive micro-trauma
- Intrinsic factors: joint ROM, poor alignment, joint laxity, muscle imbalances
- Extrinsic factors: training, surfaces, shoes, equipment
Aging
- overuse can occur at any age, but aging is a factor
- Primary aging - decline in physiological homeostasis
- secondary aging - structural and function deficits, changes on the body due to habits and behavior
Aging Nervous system
- reduced # if motor units
- reduced motor unit firing rates
- less white matter mass
Exercise and Aging
- It is never too late to start a exercise program
Osteoarthritis
- resistance training can reduce pain severity and use both eccentric and concentric training shows improved strength and tolerated by people with osteoarthritis
- degeneration of articular cartilage
Osteoporosis
- decreased mineral content and architectural remodeling changes
Aging - muscles
- loss od muscle mass
- physical inactivity
- changes in muscle structure
- more fatty tissue buildup in muscles
- increase in insulin resistance
Aging - Bone
- Bone mass decrease
- Increase in outer portion of bone
- decline in estrogen levels