Summary MUSCULOSKELETAL SYSTEM

ANATOMY, PHYSIOLOGY & PATHOLOGY
NOTES OF THE



SYSTEM
THIRD EDITION
PRE-SUMMARIZED FOR THE TIME-POOR
READY-TO-STUDY MEDICAL, PRE-MED
HIGH-YIELD NOTES USMLE OR PA STUDEN

,Table Of Contents:
#60*a3 78&%.;$;= S+/%&2#-24#$%& /(/#-*&8 <0&4'-1-)& /(% </#0-1-)& (-#+4 -5 #0+ *$4,$1-4:+1+#/1 4&4#+*
<.+4+(#+% '( 4$,,'(,#8 '(#$'#'7+ /(% .',01& '11$4#./#+% %-9(1-/%/31+ TUM %-,$*+(#4C D(,+ %-9(1-/%+%8 &-$ */&
,0--4+ #- +'#0+. <.'(# /(% 3'(% #0+*8 -. */:+ /((-#/#'-(4 %')'#/11& -( &-$. '</% -. #/31+# TVC

Anatomy & Physiology Notes:
• GENERAL OVERVIEW OF THE SKELETAL SYSTEM
• GENERAL OVERVIEW OF THE MUSCULAR SYSTEM
• GENERAL MUSCLE PHYSIOLOGY
• PRINCIPLES OF BIOMECHANICS
• MUSCLE REFLEXES
• BONES OF THE SKULL
• BONES OF THE AXIAL SKELETON
• BONES OF THE UPPER LIMBS & SHOULDER GIRDLE
• BONES OF THE LOWER LIMBS & PELVIC GIRDLE
• MUSCLES OF THE AXIAL SKELETON
• MUSCLES OF THE UPPER LIMBS & PELVIC GIRDLE
• MUSCLES OF THE LOWER LIMBS & PELVIC GIRDLE
• INNERVATION OF THE UPPER LIMBS & SHOULDER GIRDLE
• INNERVATION OF THE LOWER LIMBS & PELVIC GIRDLE
• BLOOD SUPPLY OF THE UPPER LIMBS & SHOULDER GIRDLE
• BLOOD SUPPLY OF THE LOWER LIMBS & PELVIC GIRDLE

Pathology Notes:
- BONY INJURIES
- DESCRIBING AN X-RAY
- NEUROVASCULAR COMPROMISES
- MYOSITIS
- OSTEOMYELITIS
- SEPTIC ARTHRITIS
- BONY TUMOURS
- OSTEOPOROSIS & PAGETS DISEASE
- FIBROMYALGIA
- POLYMYALGIA RHEUMATICA
- CRYSTAL ARTHROPATHIES
- OSTEOARTHRITIS
- RHEUMATOID ARTHRITIS
- SERONEGATIVE (NON-RHEUMATOID) ARTHRITIS
- ARTHRITIS & RHEUMATOLOGY CASES

, GENERAL OVERVIEW OF THE SKELETAL SYSTEM

Functions:
• Support
• Protection
• Movement
• Storage
o Minerals
§ Ca+ - used in many processes in body
§ Must be maintained at certain levels in blood.
o Marrow
§ Haematopoietic stem cells
§ Fat
• Blood Production – Haematopoiesis

Metabolism of bone & its hormonal control
• Calcitonin à Ca+ salt deposit in bone
• Parathyroid hormone à Resorption of Ca+ from bone by osteoclasts à increases blood Ca+ levels.
• Estrogen à Restrains Osteoclast activity & Promotes deposition of new bone.

, Osteoporosis:
• Bone resorption outstrips deposition à bone density decreases – risk of fractures increases.
o Cancellous bone is affected first – has a quicker turnover (remodelling rate)
o Trabeculae become porous & lighter or even disappear
o Common in Postmenopausal Women: reduced levels of Estrogen à increased osteoclast activity.




Bone Composition:
• Organic
o Collagen & other proteins
o 35%
o Flexibility
o Tensile Strength
• Inorganic
o Mineral Salts
o 65%
o Compression Strength
o Reason why it preserves so well.

Bone & Associated Tissue Histology:
• Bone
o Compact
§ Thicker
§ Denser
§ Comprised of Osteons – basic units of compact bone
• Haversian Canal
o Blood Vessels
o Nerve Fibres
• Lamellae
o Rings of Collagen Fibres around Haversian Canals
o Collagen Fibres oppose each other diagonally
o Resists torsional stress
• Lacunae
o Tiny caverns between the Lamellae
o Residences of the osteocytes
• Osteocytes
o Living cells of bone tissue
o Maintains health of bone matrix
o If an osteocyte dies, the surrounding bone matrix is resorbed by osteoclasts.
• Canaliculi
o Tiny plasma membrane extensions of the osteocytes
o Allows communication between osteocytes
o Allows nutrient sharing between osteocytes