AIPGMEE 2016 Pediatrics MCQ

The ratio of upper body segment to lower body segment changes from 1.7 at birth to 1.0 by what age?

• 2 years
• 4 years
• 7 years
• 10 years
• Puberty

Body proportions follow a predictable sequence of changes with development. The head and trunk are relatively large at birth, with progressive lengthening of the limbs throughout development, particularly during puberty. The lower body segment is defined as the length from the symphysis pubis to the floor, and the upper body segment is the height minus the lower body segment. The ratio of upper body segment divided by lower body segment (U/L ratio) equals approximately 1.7 at birth, 1.3 at 3 yr of age, and 1.0 after 7 yr of age. Higher U/L ratios are characteristic of short-limb dwarfism or bone disorders, such as rickets. 

AIPGMEE 2016 Pediatrics

1. Which of the following is the largest and most complex of the synovial joints?

A.knee

B.hip

C.elbow

D.wrist

E.ankle

ANS.A

EXPLANTION:-

The knee is the largest human joint in terms of its volume and surface area of articulating cartilage. The knee joint is also the most complex articulation in the body, and has the greatest susceptibility to injury, age-related wear and tear, inflammatory arthritis, and septic arthritis

Ref:- www.uptodate.com

Sub- orthopedics,

Topic-

2. Which ligament originates from the anterior intercondylar area of the tibia and extends to the lateral condyle of the femur?

A.posterior cruciate

B.anterior cruciate

C.medial meniscus

D.lateral meniscus

E.

ANS.B

EXPLANTION:-

The anterior cruciate ligament (ACL) is an important stabilizing ligament of the knee that is frequently injured by athletes and trauma victims.The primary function of the anterior cruciate ligament (ACL) is to control anterior translation of the tibia. The ACL also is a secondary restraint to tibial rotation as well as varus or valgus stress .The ACL originates at the posteromedial aspect of the lateral femoral condyle. It courses distally in an anterior and medial fashion to the anteromedial aspect of the tibia between the condyles. The position on the tibia is approximately 15 mm behind the anterior border of the tibial articular surface, and medial to the attachment of the anterior horn of the lateral meniscus .The ACL is often said to be comprised of two bundles: an anteromedial bundle that is tight in flexion and a posterolateral bundle that is tight in extension. The blood supply to the ACL is from branches of the middle geniculate artery and its innervation comes from the posterior articular nerve, a branch of the tibial nerve.

Ref:- www.uptodate.com

Sub- orthopedics,

Topic-

3. Which bone articulates with the distal tibia and fibula?

A.Talus

B.calcaneus

C.navicular

D.cuboid

E.

ANS.A

EXPLANTION:-

The foot can be divided into three functional parts: the hindfoot, midfoot, and forefoot [ 1 ]. The hindfoot, which consists of the talus and the calcaneus, connects to the midfoot at the midtarsal (Chopart) joint. The midfoot contains the navicular, the cuboid, and the three cuneiform bones; it connects to the forefoot at the Lisfranc joint. The forefoot includes everything distal to the Lisfranc joint, including the metatarsals, sesamoids, and phalanges

The foot has 28 bones, including 14 phalanges, seven tarsal bones (talus, calcaneus, cuboid, navicular, and three cuneiforms), five metatarsals, and two sesamoids. The bones that are clinically significant can be organized according to their dynamic articulations

The foot has four joints: the ankle (mortise), subtalar (talocalcaneal), midtarsal (Chopart), and midfoot (Lisfranc).The distal tibia and fibula form the roof of the ankle joint. The dome of the talus fits snugly into the tibia and fibula. The primary plane of movement at the ankle joint is plantarflexion/dorsiflexion.

The subtalar joint is composed of the anterior, middle, and posterior articulations between the talus and the calcaneus. They are separated laterally by the sinus tarsi and medially by the tarsal canal. The subtalar joint is responsible for hindfoot inversion/eversion and abduction/adduction.

The talonavicular and calcaneocuboid articulations comprise the midtarsal joint and demarcate the hindfoot from the midfoot. They are responsible for "unlocking" the midfoot during subtalar pronation, allowing the foot to absorb more shock, and for "locking" the midfoot during subtalar supination, allowing the foot to become a rigid lever for propulsion.

The midfoot or Lisfranc joint is the articulation between the three cuneiforms and the proximal second metatarsal. It provides rigid stability to optimize efficiency through the medial column of the foot.Ligaments  — The ankle has three main groups of ligaments

Lateral ligament complex– This complex has three components:

The anterior talofibular ligament (ATFL) connects the talus and distal fibula anteriorly.

The calcaneofibular ligament (CFL) connects the calcaneus and distal fibula directly inferior to the lateral malleolus.

The posterior talofibular ligament (PTFL) connects the talus and fibula posteriorly.

Medial ligament complex – The deltoid ligament, located on the medial side of the ankle, is a broad band of connective tissue that has four separate divisions that connect the distal tibia with the talus, calcaneus, and the navicular bones.

Tibiofibular ligament complex – The tibiofibular complex consists of the anterior and posterior tibiofibular and the interosseous membrane and ligament. This complex is responsible for maintaining the relationship between the distal tibia and fibular and preventing them from splaying apart with a cephalad force from the talus

The plantar fascia is the primary aponeurosis that originates on the plantar aspect of the calcaneus and fans out to attach to the base of each of the five metatarsal heads. It acts to reinforce the medial arch during the propulsion phase of gait. Its windlass effect on the medial longitudinal arch is important to the biomechanics of the foot during the toe-off phase.

Muscles  — The muscles of the foot and ankle originate above the ankle (extrinsics) and within the foot (intrinsics).

The extrinsic muscles permit the larger force-generating muscles to be located away from the foot and to avoid interference with the intrinsic structure of the foot.

The anterior or extensor compartment of the leg includes the following muscles:

The tibialis anterior originates on the proximal anterior tibia and courses distally in its synovial sheath beneath the extensor retinaculum to insert on both the medial cuneiform and the medial base of the first metatarsal. It dorsiflexes and inverts the foot.

The extensor hallucis longus (EHL) inserts on the dorsal aspect of the base of the distal phalanx of the great toe. It extends the great toe and dorsiflexes the foot.

The extensor digitorum longus (EDL) has a distal attachment on the middle and distal phalanges of the lateral four digits and acts to extend these lateral four digits and dorsiflex the foot.

The peroneus tertius inserts on the base of the fifth metatarsal bone and acts in a minor role in dorsiflexion and eversion of the foot.

The lateral compartment of the leg contains the peroneus longus and peroneus brevis. The peroneus longus inserts on the base of the first metatarsal bone and medial cuneiform bone and acts to evert the foot and weakly plantarflex it. The peroneus brevis inserts on the base of the fifth metatarsal and has the same action as does the peroneus longus.

The superficial posterior compartment of the leg contains the triceps surae (the gastrocnemius and soleus complex), which insert via the Achilles tendon into the posterior surface of the calcaneus. They are the force generators that plantarflex the foot and weakly evert the heel.

The deep posterior compartment of the leg contains the tibialis posterior (TP), flexor digitorum longus (FDL), and flexor hallucis longus (FHL) muscles.

Ref:- www.uptodate.com

Sub- orthopedics,

Topic-

Notes in Forensic Medicine AIPGMEE 2016

Hanging
Hanging is that form of asphyxia which is caused by suspension of the body by a ligature which encircles the neck, the constricting force being the weight of the body. The
whole weight of the body is not necessary, and only a comparatively slight force is enough to produce death. In ‘partial hanging’ the bodies are partially suspended, the toes
or feet touching the ground, or are in a sitting, kneeling, lying down, prone or any other posture. The weight of the head (5 to 6 kg) acts as the constricting force. In typical
hanging, the knot is situated over the nape of the neck ligature runs form the midline above the thyroid cartilage symmetrically upward on both sides of the neck to the
occipital region other position of knot is called Atypical Hanging. When the body is completely suspended by a Ligature with full weight acting as constricting force it is
termed as Complete Hanging,when any part of the body is in contact with the ground it is termed as Partial Hanging.
Ligature: A suicide will use any article readily available for the purpose, like a rope, metallic chains and wires, leather strap, belt, bed sheet, scarf, dhoti, saree, turban,
sacred thread, etc. The doctor should note whether the mark on the neck corresponds with the material alleged to have been used in hanging and if it is strong enough to
bear the weight and the jerk of the body. He should also note its texture and length, to know whether it was sufficient to hang. Before removing the ligature from the neck, it
should be described as to the nature and composition, width, mode of application, location and type of knot. Sometimes, the rope will break or become detached and the
deceased will be found lying on the ground with a ligature around his neck.
Symptoms: The first symptoms are loss or power and subjective sensations, such as flashes of light and ringing and hissing noises in the ears. There is intense mental
confusion, all power of to logical thought is lost; the individual can do nothing to help himself even if it were possible. These are to followed by loss of consciousness, which is
so rapid, that it is regarded as a painless form of death. Then follows a stage of convulsions. The face is distorted and livid, eyes prominent, and there is violent struggling.
Respiration stops before the heart, which may continue to beat for about 10 to 15 minutes.
Causes of Death :
1. Asphyxia : The constricting force of the ligature, causes compressive narrowing of laryngeal and tracheal lumina, and forces up the root of the tongue against the
posterior wall of the pharynx, and folds the epiglottis over the entrance of the larynx to block the airway. A tension of 15 kg. on ligature blocks the trachea.
2. Venous congestion: The jugular veins are blocked by the compression of the ligature which results in stoppage of the cerebral circulation, and a rapid rise in venous
pressure in the head. This occurs if ligature is made up of broad and soft material, which cannot sink into tissue to any depth. The jugular veins are closed by a
tension in the rope of 2kg.
3. Combined asphyxia and venous congestion: This is the commonest cause.
4. Cerebral anaemia: Pressure on the large arteries on the neck produces cerebral anaemia and immediate coma. This occurs with ligature made of thin cord, which
sinks deeply into tissues. A tension of 4 to 5kg on ligature blocks carotid arteries, and 20 kg. the vertebral arteries.
5. Reflex vagal inhibition form pressure on the vagal sheath or carotid bodies.
6. Fracture or dislocation of the cervical vertebrae.
Delayed Death: Death delayed for several days is rare. Delayed deaths occur due to (1) aspiration pneumonia, (2) infections, (3) oedema of lungs, (4) oedema of larynx, (5)
hypoxic encephalopathy, (6) infarction of brain, (7) abscess of brain, (8) cerebral softening.
The secondary effects of hanging in persons who have recovered are sometimes hemiplegia, epileptiform convulsions, amnesia, dementia, cervical cellulitis, parotitis,
retropharyngeal abscess, amnesia, and dementia.
Fatal Period : Death occurs immediately if the cervical vertebrae are fractured, or if the heart is inhibited; rapidly if cause is asphyxia, and least rapidly if coma is
responsible. The usual period is 3 to 5 minutes.
Post-mortem Appearances :
External: The ligature mark in the neck is the most important and specific sign of death from hanging. Ligature mark on the neck depends on: 1) Composition of ligature:
The pattern and texture is produced upon the skin, e.g., if thick rope is used, its texture may be impressed in the form of superficial abrasion. 2) Width and multiplicity of
ligature : When ligature is narrow, a deep groove is made because much more force per sq. cm. Of ligature is directed inwards. A broad ligature will produce only a superficial
mark. If the ligature is passed twice round the neck, a double mark, one circular, and the other oblique may be seen. The ligature may have one, two or more layers. There
may be multiple congested areas where the skin has been caught between the various layers. 3) The weight of the body suspended and the degree f the suspension: Heavier
he body and greater the proportion of the body suspended, the more marked is the ligature impression. 4) The tightness of encircling ligature: The ligature impression is
deeper opposite the point of suspension, but it may tail off vary rapidly if ligature consists of loop rather than a noose. If the noose tightness completely around the neck, the
ligature mark will be seen completely encircling the neck. 5) The length of time body has been suspended: Longer the suspension, deeper is the groove. Even a soft, board
ligature can cause a clear-cut groove if suspended long. If the ligature is cut down within a short time and a soft broad ligature has been used, there may be no external mark.
6) Position of the knot: The main force applied to the neck b ligature is opposite to the point of suspension. If the point of suspension is in occipital region, front of the neck is
involved. If in front, the depth of the groove is limited posteriorly by cervical spine. 7) Slipping of ligature during suspension: Frequently, only the portion adjacent to the knot
moves. There is a tendency for the ligature to move upwards, this being limited by the jaws. The upward movement may produce double impression of ligature. The lower
mark is usually very superficial and is connected by fine abrasions, caused by the slipping ligature, to the mark made by ligature in its final position.
Knot: It is frequently in the form of a simple slip-knot to produce a running noose or fixed by granny or reef-knot; occasionally a simple loop is used. The knot is usually on
the right or left side of the neck, ligature usually rising behind the ear to the point of suspension. Sometimes, the knot is in the occipital region and rarely under the chin. After
suspension in hanging, the knot is at higher level than the remainder of ligature, the movement of knot being due to the act of suspension. The involvement of another party
may be suggested by certain types of knots and nooses. Removal of the noose from the neck is done by cutting the noose away from e knot and tying the cut ends with
string or wire.
Ligature Mark: The ligature produces a furrow or groove in the tussue which is pale in colour, but it later becomes yellowish or yellowbrown and hard like parchment, due
to the drying of the slightly abraded skin. The course of the groove depends on whether a fixed or running noose has been used, when the loop is arranged with a fixed knot,
the curse of the mark is deepest and nearly horizontal on the side opposite to knot, but as the arms of the ligature approach the knot the mark turns upwards towards it. This
produces an inverted ‘V’ at the site of the knot, the apex of the ‘V’ corresponding with the site of the knot. An impression from a knot any be found if the ligature is tight on
the skin, usually on one or other side of the back and occasionally beneath the chin. A slip-knot may cause the noose to tighten and squeeze the skin through the full
circumference of the neck. In the case of a fixed loop with a single knot in the midline at the back of the head, the mark is seen on both sides of the neck and is directed
obliquely upwards towards the position of the knot over the back of the neck. In the case of a fixed loop with a single knot in the midline under the chin, the mark is seen on
the back and both sides of the neck, and is directed obliquely forwards towards the position of the knot over the front of the neck. In the case of fixed loop with the knot in the
region of one ear, the mark differs on each side of the neck. On the side of the knot, the mark is directed obliquely upwards to the knot, and on the other side it is directed
transversely. If the ligature is in the form of a loop, the mark will be most prominent on the part of the neck to which the head has inclined and less marked over the region of
the open angle of the loop. When a running noose is applied, the weight of the body will cause the noose to tighten in a mainly horizontal position. The mark is seen on both
sides of the neck, and is usually directed transversely across the front of the neck resembling that of a ligature mark in strangulation, except that it is likely to be seen above
the level of thyroid cartilage. If a running noose fails to tighten, the mark may resemble one produced by a fixed loop. If the noose is a belt dig into the skin. In hanging from a
low point of suspension, the groove produced by the ligature is less well marked, and may be at about the level of the upper border of the larynx and more horizontal. In partial
hanging when the body leans forward, a horizontal ligature mark may be seen. The ligature mark usually encircles the entire neck except for the place where the knot was
located. The firmer muscular tissues at the back of the neck do not show clear and deep grooves, as are teen of the depression, a thin line of congestion or haemorrhage will
be seen above and below the groove at some point, usually the deepest, if not throughout its course. Ecchymoses alone have no significance as to whether hanging was
caused during life or not, but abrasions with haemorrhage are strongly suggestive of suspension taking place during life.
The mark is situated above the level of thyroid cartilage, between the larynx and the chin in 80 percent of cases. It may be at the level of the cartilage in about 15 percent,
and below the cartilage in about 5 percent cases, especially in partial suspension. The width of the groove is about, or slightly less than the width of the ligature. Any welldefined
pattern in the ligature is match of patterns. When fresh, the ligature mark is less clear, but becomes prominent after dying for several hours. A portion of skin and
deeper tissue in relation to ligature should be examined microscopically for evidence of tissue reaction, which if present indicated ante-mortem hanging. The absence of
tissue reaction does not exclude ante-mortem hanging (Gordon, et al). however, hanging may occur without visible marks on the victim’s neck. If there is a beard. Or if a
portion of clothing is caught between the ligature and the skin, no ligature mark any be found under it.
When a folded cloth has been used, there may be great difference between the appearance of the neck mar and the size of the ligature. When fabric is pulled tight, certain
parts of it become raised into ridges, which form the ligating surface, and only these may be reproduced on the skin. When nylon, silk or terylene fabrics are used, they may
leave a mark only 2 to 3 mm wide. A loop made of soft material e.g., towel, scarf, etc. may not produce a ligature mark, but the knot may produce an abrasion due o its
firmness. If there is no ligature, the mark should be taped, as it may pick up some fibers by the ligature and facilitate the identification of the material of which the ligature
was made. The ligature mark of hanging may be reproduced by dragging a body aong the ground with ligature passed round the neck soon after death. decomposition
obliterates the ligature mark. The ligature mark may disappear after several bourns following removal of the ligature.
In obese persons or infants, skin folds on the neck may resemble a ligature mark, especially after refrigeration of the body has caused coagulation of the subcutaneous fat.
When there is swelling of the neck tissues due to decomposition, marks may be produced by jewellery or clothing.
Partial Hanging: Hanging may occur simply by leaning against the noose secured to a chair or door knob, the leg of a table, a bedpost or rail, or the handrail of a
staircase, which is slightly higher than the position of the head, the deceased being in a kneeling position, or fall back or forward and lie prone with only the face and chest off
the ground. In these cases, the constricting face is less and congestive changes are more marked. Hanging may occur when pressure is applied only at the font of the neck,
e.g. by the arm of a chair, rung of a ladder, etc. in such case, the marks on the neck may be indistinct or absent.

AIPGMEE 2016 MCQ Embryology

   During spermatogenesis, histone is replaced by which of the following, to allow better packing of the condensed chromatin in the head of the spermatozoon?

o    A. Inhibin

o    B. Prostaglandin E

o    C. Testosterone

o    D. Protamine

o    E. Androgen-binding protein

The function of sperm is to safely transport the haploid paternal genome to the egg containing the maternal genome. The subsequent fertilization leads to transmission of a new unique diploid genome to the next generation. Before the sperm can set out on its adventurous journey, remarkable arrangements need to be made during the post-meiotic stages of spermatogenesis. Haploid spermatids undergo extensive morphological changes, including a striking reorganization and compaction of their chromatin. Thereby, the nucleosomal, histone-based structure is nearly completely substituted by a protamine-based structure. This replacement is likely facilitated by incorporation of histone variants, post-translational histone modifications, chromatin-remodeling complexes, as well as transient DNA strand breaks. The consequences of mutations have revealed that a protamine-based chromatin is essential for fertility in mice but not in Drosophila. Nevertheless, loss of protamines in Drosophila increases the sensitivity to X-rays and thus supports the hypothesis that protamines are necessary to protect the paternal genome. Pharmaceutical approaches have provided the first mechanistic insights and have shown that hyperacetylation of histones just before their displacement is vital for progress in chromatin reorganization but is clearly not the sole inducer. In this review, we highlight the current knowledge on post-meiotic chromatin reorganization and reveal for the first time intriguing parallels in this process in Drosophila and mammals. We conclude with a model that illustrates the possible mechanisms that lead from a histone-based chromatin to a mainly protamine-based structure during spermatid differentiation. This article is part of a Special Issue entitled: Chromatin and epigenetic regulation of animal development.

AIPGMEE 2016 Pathology MCQ

A 5-year-old child has a history of recurrent bacterial
infections, including pneumonia and otitis media. Analysis
of leukocytes collected from the peripheral blood shows a
deficiency in myeloperoxidase. A reduction in which of the
following processes is the most likely cause of this child’s increased
susceptibility to infections?
A Hydrogen peroxide (H2O2) elaboration
B Hydroxy-halide radical (HOCl–) formation
C Failure of migration resulting from complement
deficiency
D Phagocytic cell oxygen consumption
E Prostaglandin production

Answer - B Myeloperoxidase is present in the azurophilic granules
of neutrophils. It converts H2O2 into HOCl–, a powerful
oxidant and antimicrobial agent. Degranulation occurs
as phagolysosomes are formed with engulfed bacteria in
phagocytic vacuoles within the neutrophil cytoplasm. Oxygen
consumption with an oxidative or respiratory burst after
phagocytosis is aided by glucose oxidation and activation
of neutrophil NADPH oxidase, resulting in generation of
superoxide that is converted by spontaneous dismutation
to H2O2. In contrast, prostaglandin production depends on
a functioning cyclooxygenase pathway of arachidonic acid
metabolism.

AIPGMEE 2016 MCQ Pediatrics

1.orthopedics Topic-  

Which of the following is the largest and most complex of the synovial joints?

A.knee

B.hip

C.elbow

D.wrist

E.ankle

ANS.A

EXPLANTION:-

The knee is the largest human joint in terms of its volume and surface area of articulating cartilage. The knee joint is also the most complex articulation in the body, and has the greatest susceptibility to injury, age-related wear and tear, inflammatory arthritis, and septic arthritis

Ref:- www.uptodate.com

2.orthopedics Topic-  

Which ligament originates from the anterior intercondylar area of the tibia and extends to the lateral condyle of the femur?

A.posterior cruciate

B.anterior cruciate

C.medial meniscus

D.lateral meniscus

ANS.B

EXPLANTION:-

The anterior cruciate ligament (ACL) is an important stabilizing ligament of the knee that is frequently injured by athletes and trauma victims.The primary function of the anterior cruciate ligament (ACL) is to control anterior translation of the tibia. The ACL also is a secondary restraint to tibial rotation as well as varus or valgus stress .The ACL originates at the posteromedial aspect of the lateral femoral condyle. It courses distally in an anterior and medial fashion to the anteromedial aspect of the tibia between the condyles. The position on the tibia is approximately 15 mm behind the anterior border of the tibial articular surface, and medial to the attachment of the anterior horn of the lateral meniscus .The ACL is often said to be comprised of two bundles: an anteromedial bundle that is tight in flexion and a posterolateral bundle that is tight in extension. The blood supply to the ACL is from branches of the middle geniculate artery and its innervation comes from the posterior articular nerve, a branch of the tibial nerve.

Ref:- www.uptodate.com

3.orthopedics Topic-  

Which bone articulates with the distal tibia and fibula?

A.Talus

B.calcaneus

C.navicular

D.cuboid

ANS.A

EXPLANTION:-

The foot can be divided into three functional parts: the hindfoot, midfoot, and forefoot [ 1 ]. The hindfoot, which consists of the talus and the calcaneus, connects to the midfoot at the midtarsal (Chopart) joint. The midfoot contains the navicular, the cuboid, and the three cuneiform bones; it connects to the forefoot at the Lisfranc joint. The forefoot includes everything distal to the Lisfranc joint, including the metatarsals, sesamoids, and phalanges

The foot has 28 bones, including 14 phalanges, seven tarsal bones (talus, calcaneus, cuboid, navicular, and three cuneiforms), five metatarsals, and two sesamoids. The bones that are clinically significant can be organized according to their dynamic articulations

The foot has four joints: the ankle (mortise), subtalar (talocalcaneal), midtarsal (Chopart), and midfoot (Lisfranc).The distal tibia and fibula form the roof of the ankle joint. The dome of the talus fits snugly into the tibia and fibula. The primary plane of movement at the ankle joint is plantarflexion/dorsiflexion.

The subtalar joint is composed of the anterior, middle, and posterior articulations between the talus and the calcaneus. They are separated laterally by the sinus tarsi and medially by the tarsal canal. The subtalar joint is responsible for hindfoot inversion/eversion and abduction/adduction.

The talonavicular and calcaneocuboid articulations comprise the midtarsal joint and demarcate the hindfoot from the midfoot. They are responsible for "unlocking" the midfoot during subtalar pronation, allowing the foot to absorb more shock, and for "locking" the midfoot during subtalar supination, allowing the foot to become a rigid lever for propulsion.

The midfoot or Lisfranc joint is the articulation between the three cuneiforms and the proximal second metatarsal. It provides rigid stability to optimize efficiency through the medial column of the foot.Ligaments  — The ankle has three main groups of ligaments

Lateral ligament complex– This complex has three components:

The anterior talofibular ligament (ATFL) connects the talus and distal fibula anteriorly.

The calcaneofibular ligament (CFL) connects the calcaneus and distal fibula directly inferior to the lateral malleolus.

The posterior talofibular ligament (PTFL) connects the talus and fibula posteriorly.

Medial ligament complex – The deltoid ligament, located on the medial side of the ankle, is a broad band of connective tissue that has four separate divisions that connect the distal tibia with the talus, calcaneus, and the navicular bones.

Tibiofibular ligament complex – The tibiofibular complex consists of the anterior and posterior tibiofibular and the interosseous membrane and ligament. This complex is responsible for maintaining the relationship between the distal tibia and fibular and preventing them from splaying apart with a cephalad force from the talus

The plantar fascia is the primary aponeurosis that originates on the plantar aspect of the calcaneus and fans out to attach to the base of each of the five metatarsal heads. It acts to reinforce the medial arch during the propulsion phase of gait. Its windlass effect on the medial longitudinal arch is important to the biomechanics of the foot during the toe-off phase.

Muscles  — The muscles of the foot and ankle originate above the ankle (extrinsics) and within the foot (intrinsics).

The extrinsic muscles permit the larger force-generating muscles to be located away from the foot and to avoid interference with the intrinsic structure of the foot.

The anterior or extensor compartment of the leg includes the following muscles:

The tibialis anterior originates on the proximal anterior tibia and courses distally in its synovial sheath beneath the extensor retinaculum to insert on both the medial cuneiform and the medial base of the first metatarsal. It dorsiflexes and inverts the foot.

The extensor hallucis longus (EHL) inserts on the dorsal aspect of the base of the distal phalanx of the great toe. It extends the great toe and dorsiflexes the foot.

The extensor digitorum longus (EDL) has a distal attachment on the middle and distal phalanges of the lateral four digits and acts to extend these lateral four digits and dorsiflex the foot.

The peroneus tertius inserts on the base of the fifth metatarsal bone and acts in a minor role in dorsiflexion and eversion of the foot.

The lateral compartment of the leg contains the peroneus longus and peroneus brevis. The peroneus longus inserts on the base of the first metatarsal bone and medial cuneiform bone and acts to evert the foot and weakly plantarflex it. The peroneus brevis inserts on the base of the fifth metatarsal and has the same action as does the peroneus longus.

The superficial posterior compartment of the leg contains the triceps surae (the gastrocnemius and soleus complex), which insert via the Achilles tendon into the posterior surface of the calcaneus. They are the force generators that plantarflex the foot and weakly evert the heel.

The deep posterior compartment of the leg contains the tibialis posterior (TP), flexor digitorum longus (FDL), and flexor hallucis longus (FHL) muscles.

Ref:- www.uptodate.com

4.orthopedics Topic-  

Osteocytes are located in minute, bony chambers called

A.interestitium

B.matrix

C.lacuna

D.cortex

E.canaliculi

ANS.C

EXPLANTION:-

The skeleton is a highly dynamic organ that constantly undergoes changes and regeneration. It consists of specialized bone cells, mineralized and unmineralized connective tissue matrix, and spaces that include the bone marrow cavity, vascular canals, canaliculi, and lacunae containing osteocytes. Bone also contains water, which represents at least 25 percent of its wet weight and provides much of its unique strength and resilience

The skeleton has both structural and metabolic functions:

Its structural function is critical for locomotion, respiration, and protection of internal organs. The structural connection between the skeleton and the hematopoietic system is particularly intimate; these two systems share both cells and local regulatory factors.

Its metabolic function is largely as a storehouse for calcium, phosphorus, and carbonate, and it can contribute to buffering changes in hydrogen ion concentration.

Ref:- www.uptodate.com

5.orthopedics Topic-  

Bone grafts are usually taken from the

A.femur

B.fibula

C.sternum

D.iliac crest

E.radius

ANS.D

EXPLANTION:-

Transplantation of structured or morcelized autologous corticocancellous bone obtained from the iliac crest is the most frequently used technique.

Allografts and metal endoprostheses are common means of reconstructing bone defects that result from sarcoma surgery. Other methods listed below may be preferred to fill the osseous defect depending on the clinical situation and the availability of the product.

Allografts  — While autologous bone grafting is of limited use in patients undergoing resection of bone tumors because of the large size of the defect, allografts have been successfully used for many years. Allografts provide the potential for long-lasting reconstruction of large bony defects by providing a structural lattice for the ingrowth of the patient's own bone elements .The host normal tissue slowly invades the allograft by creeping substitution of normal bone and vascular elements at the osteosynthesis site and periosteum. Large segments of allografted bone probably do not completely fill with autogenous bone, and this may lead to allograft fracture over time (this occurs in about 18 percent of the cases). The articular cartilage is slowly replaced by an inflammatory pannus-like tissue, and some patients may ultimately require joint resurfacing.

Allografts are available from tissue banks and need to be matched to the size of the resected bone. Although bone is a relative nonantigenic structure, matching for the class II major histocompatibility antigens results in better clinical outcomes.

Ref:- www.uptodate.com

6.Pediatrics Topic-  GENETICS

Regarding Cat-eye syndrome

1. Mental retardation is not seen

2. Congenital heart disease is common

3. Partial deletion of short arm of 5th chromosome

4. Partial trisomy of 22nd chromosome

A.1,2 and 3 are correct

B.1 and 3 are correct

C.2 and 4 are correct

D.Only 4 is correct

ANS.C

EXPLANTION:-

Cat eye syndrome is due to duplication (partial trisomy) of

22nd chromosome. It is characterized by:

• Coloboma

• Anal atresia

• Mental retardation

• Pre-auricular tags or slits

• Congenital heart disease

Cat cry syndrome( cri-du-chat syndrome) is due to

partial deletion of the short arm of 5th chromosome.

Cat eye syndrome (CES), or Schmid–Fraccaro syndrome, is a rare condition caused by the short arm (p) and a small section of the long arm (q) of human Chromosome 22 being present three (trisomic) or four times (tetrasomic) instead of the usual two times. The term "Cat Eye" syndrome was coined because of the particular appearance of the vertical colobomas in the eyes of some patients. However, over half of the CES patients in the literature do not present with this trait. There is no significant reduction in life expectancy in patients who are not afflicted with one of CES life threatening abnormalities.

Ref:- http://en.wikipedia.org/wiki/Cat_eye_syndrome

7.Pediatrics Topic-  GENETICS

'X' chromosome belongs to which of the following groups

A.C

B.D

C.G

D.None of above

ANS.C

EXPLANTION:-

Chromosomes can be classified into 7 groups - A to G.

A-1,2, 3; B-4&5; C-6 to 12 and X; D-13,14,

15; E-16, 17,18; F - 19&20; G-21, 22 and Y.

Thus, Trisomy D is Patau syndrome (Tri-13), Trisomy E is Edwards syndrome (or Tri-18) and

TrisomyG is Down syndrome (Trisomy 21).

The rule of karyotyping is to arrange 22 autosomes following the size and sex chromosomes, X and Y, at the end. Chromosomes are classified into seven groups, A to G, by the length and centromere position.

Ref:- http://www.rerf.jp/dept/genetics/giemsa_4_e.html