Orthopedic Surgery

1. Orthopedic Surgery

2. Bones • Know the bones of the skeleton!

3. 206 bones make up the skeleton • Axial • 80 bones that make up the skull, vertebrae and rib cage • Appendicular • 126 bones that make up the limbs • Each upper extremity is composed of 32 bones • Each lower extremity is made up of 31 bones

5. Cortical Bone • aka: Compact Bone • Hard bone forming the outer shell, acting as the main supporting structure

6. Cancellous Bone • aka: Spongy Bone or Spongiosa • Soft, spongy bone located at the iliac crest, tibia, sternum, and ends of long bones • Contains the red bone marrow for hematopoesis

7. Periosteum • Strong, fibrous membrane which covers bone, except at joints • Blood supply and innervation penetrates the periosteum and enters the bone through structures known as Volkmann’s canals

8. Haversian System • Circular bone tissue, consisting of concentric lamellae (thin leaf or plate) in the bone around a central blood vessel canal

9. Shape classifications • Long • humerus, radius, ulna, femur, tibia, fibula • Short • bones of the hands and feet • Flat • scapula, patella, sternum, pelvic bones, ribs • Irregular • vertebrae, skull

10. Long Bones • Ends of long bones (epiphysis) • Consists of spongy or cancellous bone • Epiphyseal plate (aka growth plate) • Separates the epiphysis from the diaphysis until skeletal maturity

12. Long Bones • Shaft of long bones (diaphysis) • Consists of compact or cortical bone • Endosteum • Tissue similar to periosteum which lines the inside of the shaft • Yellow marrow • Found in the medullary canal, it has a high adipose content

13. Bony Features • Trochanter • Bony projections which is the point of attachment for muscles • Condyle • Rounded projection at the ends of bones • Fossa • Hollow or depression in a bone

14. Articular Cartilage • Smooth, relatively firm, compressible tissue found at the ends of long bones • Cushions most articular surfaces • Does not have a direct blood supply, and is devoid of lymphatics and nerves

15. Articular Cartilage • Derives its nutrition from synovial fluid • The synovial membrane, a fine membrane lining the joint capsule, secretes synovial fluid. It is similar to egg albumin, and contains macrophages and white blood cells to keep the joint free of debris and bacteria • Bursa- (AKA- the joint capsule) is a tough, fibrous connective tissue

16. Ligaments • Bands of flexible, tough, fibrous tissue that join the articular surfaces of bones and cartilage

17. Tendons • Bands of extremely strong, flexible fibrous tissue that attach muscles to the periosteum of bones • Tendons are encased in the synovial membrane of moveable joints

18. Muscles • Know your major skeletal muscle groups !

19. Muscles • Contractile tissue, skeletal muscle tissue is striated and voluntary • Are covered by fascia • Skeletal muscles make up about 23% of the female and 40% of the male body weight

21. Muscles • Contract in response to signals from the nervous system, and neurotransmitters, such as acetylcholine • Origin • Proximal attachment • Insertion • Distal attachment

22. Bone Healing • Inflammation (hemorrhage) • Cellular proliferation (granulation) • Callus formation • Ossification (consolidation) • Remodeling

23. Hematoma Formation • A.K.A. -Inflammatory stage • Begins at the time of injury and lasts approximately 2 days • Fracture hematoma is formed at this time as a result of blood from the injury • The blood clot serves as a foundation for the next stage

25. Cellular Proliferation • Begins approximately on the 2nd day of the event • Macrophages debride the area and allow for the formation of a fibrin mesh that seals the approximated edges of the fracture site

26. Cellular Proliferation • A soft tissue periosteal callus is formed on the cortex of the fractured bone by the collagen producing fibroblasts and osteoblasts

27. Callus Formation • Lasts 3-4 weeks • Soft tissue growth continues and the bone fragments grow toward one another, bridging the gap

28. Callus Formation • Osteoblasts form a matrix of collagen that invades the periosteal callus bridging the fracture site and uniting the two ends of bone • Fibrous tissue, cartilage, and immature bone stabilize the fracture site

29. Ossification • Begins 2-3 weeks following the injury and can last 3-4 months • The matrix of osteoblasts, now called an osteoid, calcifies, firmly uniting the bone • The bone is now able to accept mineral deposits

30. Remodeling • The maintenance stage of normal bone. • Following a fracture any devitalized tissue is removed and new bone is organized to provide maximum support and function

31. Remodeling • Osteoblastic and osteoclastic activity should be equal, constantly reforming the bone • Remodeling process continues throughout the life cycle, and is affected by local stress on the individual bone, circulation, nutrition, and hormones

32. Considerations

33. Osteomyelitis • Infection in bone • Acute may cause nonunion of fractures • Chronic may remain for life, and may cause loss of the extremity

34. Osteomyelitis • Meticulous attention to aseptic technique is critical • Lock doors • Stay for the whole case • Laminar air flow

35. Precautions for the protection of the OR team • Sharp bony fragments and instrumentation can be hazardous • Transmission of blood borne pathogens is possible because of areosolization of bone and debris during sawing and drilling, powered irrigation units, and the use of heavy instrumentation

36. Precautions for the protection of the OR team • Wear protective attire • Knee high waterproof shoe covers or boots • Fluid impervious gown or a waterproof apron under the gown • Protective eyewear, including full face shield when splatter is anticipated, or a space suit type helmet

37. Precautions for the protection of the OR team • Double gloving • Clean gowning and gloving • Scrub person gowns and gloves off a separate table or mayo stand, NOT the backtable • Scrub person should change their own gloves before gowning and gloving another person during the procedure

38. Adduction Move toward the midline Varus Abnormal position in which a part of a limb is bent or turned toward the midline Abduction Move away from the midline Valgus Abnormal position in which a part of a limb is bent or turned away from the midline Directional Terms

39. Flexion Decreasing the angle of the joint Extension Increasing the angle of the joint Figure of four Bending the lower leg toward the midline so that the ankle of one leg is on the knee of the other leg (arthroscopy) Directional Terms

40. Bone Grafts • Usually obtained from the iliac crest • Save all bone during procedures until the end of the case • May use or donate bone from/to the bone bank • Autograft- self • Allograft- donor

41. Prosthetic Implants • Frequently are under consignment • Made of non-magnetic and electrolytically inert metals, such as stainless steel, cobalt and titanium alloys, or of polymers such as silicone and polyethylene • Some have a porous coating to allow ingrowth of bone over a portion of the implant

42. Prosthetic Implants • Implants should not be flash sterilized • Must be run on a standard cycle, with appropriate biological monitoring • Methyl Methacrylate (bone cement) may be used to reinforce fixation • Fumes are irritating to the mucous membranes, some contacts, and could possibly be toxic to the liver

43. Pneumatic Tourniquets • Maximum inflation times • Upper extremity- 1 hour • Lower extremity- 2 hours • Esmarch bandage • Used to exsanguinate the extremity prior to inflation

44. Traction • Used pre, intra, or postoperatively • Used to reduce a fracture, stabilize a joint, and align a body part • Skeletal traction is frequently applied in the OR

46. Fracture Table • Used for procedures requiring traction, image intensification, etc. • Allows for both AP and Lateral C-arm use

47. Considerations • Unit beds are used to transport patients, and should be decontaminated • Internal or external bone growth stimulators may be used

48. Considerations • Antibiotic irrigation is used frequently • If irrigating an extremity, place an emesis basin below area to be irrigated to catch the solution • Stainless steel suture may be used for tendon, ligament or bone repairs

50. Casts • Used to immobilize body part until healing occurs • Fiberglass Casts • Woven fiberglass tape with a water-activated polyurethane resin • Lighter and thinner, yet stronger than a plaster cast • Provides better ventilation than a plaster cast