2. Introduction to the profession. Regeneration of bone tissue

3. Cartilage--function, types, location Cartilage--function, types, location Bone Tissue--structure, types Bone Tissue--structure, types Long Bone Structure and Development Long Bone Structure and Development Most common bone problems Most common bone problems –Fractures –Osteoporosis Cartilage and Bone

4. What is cartilage? Skeletal tissue--maintains certain shape and form Skeletal tissue--maintains certain shape and form Very resilient (bouncy or rubbery), mostly water Very resilient (bouncy or rubbery), mostly water Grows fast--forms embryonic skeleton Grows fast--forms embryonic skeleton

5. Kinds of cartilage Hyaline cartilage--most common, found in joints Hyaline cartilage--most common, found in joints Elastic cartilage--epiglottis, ear Elastic cartilage--epiglottis, ear Fibrocartilage--annular fibrosis of intervertebral disk, menisci of knee Fibrocartilage--annular fibrosis of intervertebral disk, menisci of knee

6. M & M Figure 6.1

7. Bones provide: Support and movement (limbs, axial skeleton) Support and movement (limbs, axial skeleton) Protection (skull bones) Protection (skull bones) Mineral storage Mineral storage Blood cell development (long bone marrow) Blood cell development (long bone marrow) Bone is made up of: 35% collagen, ground substance and cells 65% calcium (hydroxyapetite)

8. Bone is alive!! Bone cell types: Osteoblasts: Make and deposit components of bone extracellular matrix Osteoblasts: Make and deposit components of bone extracellular matrix Osteoclasts: Degrade and resorb bone for remodeling Osteoclasts: Degrade and resorb bone for remodeling Osteocytes: “watcher cells” Sit in bone and monitor its current status Osteocytes: “watcher cells” Sit in bone and monitor its current status

9. Types of bony tissue Compact Bone Compact Bone –Dense tissue at surface of bones –Haversian canals –Osteocytes in lacunae –Highly vascularized –Fig. 6.6, p. 138

11. Types of bony tissue Trabecular (“spongy”) bone Trabecular (“spongy”) bone –Trabeculae (oriented to give mechanical strength) –Interior of long bones, skull bones –Epiphyses of long bones –Intramembranous ossification (osteoblasts lay down bone around blood vessels in connective tissues of dermis (after 8 weeks of development)

12. Structure of a long bone Diaphysis (shaft) Diaphysis (shaft) Epiphysis Epiphysis –Proximal –Distal Compact bone Compact bone Spongy bone Spongy bone Periosteum Periosteum Medullary cavity Medullary cavity Articular/hyaline cartilage Articular/hyaline cartilage Epyphyseal (growth) plates Epyphyseal (growth) plates Fig. 6.3, p. 135

14. Bone Tissue within a Bone

15. Why do bones need to “remodel?”

16. Endochondral Ossification 1. Cartilage model 2. Bone collar forms in diaphysis (dense bone) Cartilage chondrocytes in center of diaphysis die and cartilage disintegrates 3. Periosteal bud enters diaphysis Makes spongy bone at ends of diaphysis (primary ossification center) 4. Epiphysis begins to ossify (secondary ossification center) 5. Hyaline cartilage remains only at Epiphyseal surfaces (articular surfaces of joints) Epiphyseal growth plates between diaphysis and epiphysis (primary and secondary ossification centers on either side) Fig. 6.9, p. 141

19. Endochondral ossification centers—newly formed bone within cartilage shown is stained red

20. Osteoclasts Osteoblasts “Dig holes” with hydrochloric acid “Dig holes” with hydrochloric acid Degrades calcium Degrades calcium Phagocytize collagen fibers and dead osteocytes Phagocytize collagen fibers and dead osteocytes Line tubes (Haversian canals) left by osteoclasts Line tubes (Haversian canals) left by osteoclasts Lay down new bone in circular concentric lamellae Lay down new bone in circular concentric lamellae Unique to warm- blooded animals-- dinosaurs??? Unique to warm- blooded animals-- dinosaurs???

21. Bone Fractures Treatment is reduction Treatment is reduction –Closed--set in place by physical manipulation from outside body –Open--surgical placement of pins or screws Healing Healing –Hematoma –Fibrocartilaginous callus –Bony calllus –Remodeling by osteoclasts/osteoblasts Types of Fractures Types of Fractures

25. Fracture repair

26. Calcium regulation is negative feedback mechanis m

27. Osteoporosis Affects elderly, especially women Affects elderly, especially women Bone resorption proceeds faster than deposition Bone resorption proceeds faster than deposition Low estrogen levels implicated but estrogen replacement now considered risky Low estrogen levels implicated but estrogen replacement now considered risky Importance of calcium in diet??? Importance of calcium in diet??? Leads to fractures Leads to fractures –Compression fractures of vertebrae –Neck of femur

28. Bone grafts and artificial bone Widely used cutting-edge technologies Widely used cutting-edge technologies Bone cells highly regenerative and move into any suitable matrix Bone cells highly regenerative and move into any suitable matrix –Use bone pieces from same body—fibula –Use crushed bone from cadavers –Use bone substitutes—coral, synthetics— ”nanotechnology” Applications are numerous Applications are numerous –Jaw bone filler for dental work –Birth defects –Osteoporosis –Bone repair

29. Introduction Approximately 5% of all long bone fractures will result in nonunions and even more in delayed unions Approximately 5% of all long bone fractures will result in nonunions and even more in delayed unions

30. Delayed Union The exact time when a given fracture should be united cannot be defined The exact time when a given fracture should be united cannot be defined Union is delayed when healing has not advanced at the average rate for the location and type of fracture (Btn 3-6 mths) Union is delayed when healing has not advanced at the average rate for the location and type of fracture (Btn 3-6 mths) Treatment usually is by an efficient cast that allows as much function as possible can be continued for 4 to 12 additional weeks Treatment usually is by an efficient cast that allows as much function as possible can be continued for 4 to 12 additional weeks

31. Delayed Union cont. If still nonunited a decision should be made to treat the fracture as nonunion If still nonunited a decision should be made to treat the fracture as nonunion External ultrasound or electrical stimulation may be considered External ultrasound or electrical stimulation may be considered Surgical treatment should be carried out to remove interposed soft tissues and to oppose widely separated fragments Surgical treatment should be carried out to remove interposed soft tissues and to oppose widely separated fragments Iliac grafts should be used if plates and screws are placed but grafts are not usually needed when using intramedullary nailing, unless reduction is done open Iliac grafts should be used if plates and screws are placed but grafts are not usually needed when using intramedullary nailing, unless reduction is done open

32. Nonunion FDA defined nonunion as “established when a minimum of 9 months has elapsed since fracture with no visible progressive signs of healing for 3 months” FDA defined nonunion as “established when a minimum of 9 months has elapsed since fracture with no visible progressive signs of healing for 3 months” Every fracture has its own timetable (ie long bone shaft fracture 6 months, femoral neck fracture 3 months) Every fracture has its own timetable (ie long bone shaft fracture 6 months, femoral neck fracture 3 months)

33. Delayed/Nonunion Factors contributing to development: Systemic Systemic Local Local

34. Delayed/Nonunion cont. Systemic factors: Metabolic Metabolic Nutritional status Nutritional status General health General health Activity level Activity level Tobacco and alcohol use Tobacco and alcohol use

35. Delayed/Nonunion cont. Local factors Open Open Infected Infected Segmental (impaired blood supply) Segmental (impaired blood supply) Comminuted Comminuted Insecurely fixed Insecurely fixed Immobilized for an insufficient time Immobilized for an insufficient time Treated by ill-advised open reduction Treated by ill-advised open reduction Distracted by (traction/plate and screws) Distracted by (traction/plate and screws) Irradiated bone Irradiated bone Delayed weight-bearing > 6 weeks Delayed weight-bearing > 6 weeks Soft tissue injury > method of initial treatment Soft tissue injury > method of initial treatment

36. Nonunion cont. Nonunited fractures form two types of pseudoarthrosis: Hypervascular or hypertrophic Hypervascular or hypertrophic Avascular or atrophic Avascular or atrophic

37. Nonunion cont. Hypervascular or Hypertrophic: 1. Elephant foot (hypertophic, rich in callus) 2. Horse foot (mildly hypertophic, poor in callus) 3. Oligotrophic (not hypertrophic, no callus) Hypervascular nonunions. A, "Elephant foot" nonunion. B, "Horse hoof" nonunion. C, Oligotrophic nonunion (see text). (Redrawn from Weber BG, Cech O, eds: Pseudarthrosis, Bern, Switzerland, 1976, Hans Huber.) Hypervascular nonunions. A, "Elephant foot" nonunion. B, "Horse hoof" nonunion. C, Oligotrophic nonunion (see text). (Redrawn from Weber BG, Cech O, eds: Pseudarthrosis, Bern, Switzerland, 1976, Hans Huber.)

38. Nonunion cont. Avascular or Atrophic Torsion wedge (intermediate fragment) Torsion wedge (intermediate fragment) Comminuted (necrotic intermediate fragment) Comminuted (necrotic intermediate fragment) Defect (loss of fragment of the diaphysis) Defect (loss of fragment of the diaphysis) Atrophic (scar tissue with no osteogenic potential is replacing the missing fragment) Atrophic (scar tissue with no osteogenic potential is replacing the missing fragment) Avascular nonunions. A, Torsion wedge nonunion. B, Comminuted nonunion. C, Defect nonunion. D, Atrophic nonunion (see text). (Redrawn from Weber BG, Cech O, eds: Pseudarthrosis, Bern, Switzerland, 1976, Hans Huber.) Avascular nonunions. A, Torsion wedge nonunion. B, Comminuted nonunion. C, Defect nonunion. D, Atrophic nonunion (see text). (Redrawn from Weber BG, Cech O, eds: Pseudarthrosis, Bern, Switzerland, 1976, Hans Huber.)

39. Nonunion cont. Classification (Paley et al) Type A<2cm of bone loss Type A<2cm of bone loss A1 (Mobile deformity) A1 (Mobile deformity) A2 (fixed deformity) A2 (fixed deformity) A2-1 stiff w/o deformity A2-1 stiff w/o deformity A2-2 stiff w/ fixed deformity A2-2 stiff w/ fixed deformity Type B>2cm of bone loss Type B>2cm of bone loss B1 w/ bony defect B1 w/ bony defect B2 loss of bone length B2 loss of bone length B3 both B3 both A, Type A nonunions (less than 1 cm of bone loss): A1, lax (mobile); A2, stiff (nonmobile) (not shown); A2-1, no deformity; A2-2, fixed deformity. B, Type B nonunions (more than 1 cm of bone loss): B1, bony defect, no shortening; B2, shortening, no bony defect; B3, bony defect and shortening. A, Type A nonunions (less than 1 cm of bone loss): A1, lax (mobile); A2, stiff (nonmobile) (not shown); A2-1, no deformity; A2-2, fixed deformity. B, Type B nonunions (more than 1 cm of bone loss): B1, bony defect, no shortening; B2, shortening, no bony defect; B3, bony defect and shortening.

41. Nonunion cont. Treatment: 1. Elecrical 2. Electromagnatic 3. Ulrasound 4. External fixation (ie deformity, infection, bone loss) 5. Surgical Hypertrophic: stable fixation of fragments Hypertrophic: stable fixation of fragments Atrophic: decortication and bone grafting Atrophic: decortication and bone grafting According to classification: According to classification: type A : restoration of alignment, compression type A : restoration of alignment, compression type B : cortical osteotomy, bone transport or lengthening type B : cortical osteotomy, bone transport or lengthening

42. Nonunion cont. Surgical guidelines: Good reduction Good reduction Bone grafting Bone grafting Firm stabilization Firm stabilization

43. Nonunion cont. Reduction of the fragments: Extensive dissection is undesirable, leaving periosteum, callus, and fibrous tissue to preserve vascularity and stability, resecting only the scar tissue and the rounded ends of the bones Extensive dissection is undesirable, leaving periosteum, callus, and fibrous tissue to preserve vascularity and stability, resecting only the scar tissue and the rounded ends of the bones External fixator, Intramedullary nailing, Ilizarov frame External fixator, Intramedullary nailing, Ilizarov frame

44. Nonunion cont. Bone Grafting origins: Autogenous “the golden standard” Autogenous “the golden standard” Allograft Allograft Synthetic substitute Synthetic substitute

45. Nonunion cont. Bone grafting techniques: Onlay Onlay Dual onlay Dual onlay Cancellous insert Cancellous insert Massive sliding graft Massive sliding graft Whole fibular transplant Whole fibular transplant Vascularized free fibular graft Vascularized free fibular graft Intamedullary fibular graft Intamedullary fibular graft

46. Dual onlay Nonunion of tibial shaft treated by dual onlay grafts Nonunion of tibial shaft treated by dual onlay grafts

47. Massive sliding graft Gill massive sliding graft Gill massive sliding graft

48. Whole fibular transplant Bridging of bone defect with whole fibular transplant. A, Defect in radius was caused by shotgun wound. B and C, Ten months after defect was spanned by whole fibular transplant, patient had 25% range of motion in wrist, 50% pronation and supination, and 80% use of fingers. Bridging of bone defect with whole fibular transplant. A, Defect in radius was caused by shotgun wound. B and C, Ten months after defect was spanned by whole fibular transplant, patient had 25% range of motion in wrist, 50% pronation and supination, and 80% use of fingers.

49. Vascularized free fibular graft Posteroanterior and lateral roentgenograms made 3 years after fibular transfer, showing excellent remodeling with fracture healing. (From Duffy GP, Wood MB, Rock MG, Sim FH: J Bone Joint Surg 82A:544, 2000.) Posteroanterior and lateral roentgenograms made 3 years after fibular transfer, showing excellent remodeling with fracture healing. (From Duffy GP, Wood MB, Rock MG, Sim FH: J Bone Joint Surg 82A:544, 2000.)

50. Intamedullary fibular graft Anteroposterior roentgenogram of humerus 5 months after insertion of fibular allograft and compression plating with a 4.5-mm dynamic compression plate revealing evidence of bridging callus formation and incorporation of the allograft. (From Crosby LA, Norris BL, Dao KD, McGuire MH: Am J Orthop 29:45, 2000.) Anteroposterior roentgenogram of humerus 5 months after insertion of fibular allograft and compression plating with a 4.5-mm dynamic compression plate revealing evidence of bridging callus formation and incorporation of the allograft. (From Crosby LA, Norris BL, Dao KD, McGuire MH: Am J Orthop 29:45, 2000.)

51. Nonunion cont. Stabilization of bone fragments: Internal fixation (hypertrophic #): intamedullary, or plates and screws Internal fixation (hypertrophic #): intamedullary, or plates and screws External fixation(defects associated#): External fixation(defects associated#): ie Ilizarov ie Ilizarov

52. Internal fixation Roentgenograms of patient with subtrochanteric nonunion for 22 years treated with locked second generation femoral nail. A, Preoperatively. B, Postoperatively. Roentgenograms of patient with subtrochanteric nonunion for 22 years treated with locked second generation femoral nail. A, Preoperatively. B, Postoperatively.

53. Ilizarov Bifocal osteosynthesis with Ilizarov fixator after debridement of necrotic segments, as recommended by Catagni. Bifocal osteosynthesis with Ilizarov fixator after debridement of necrotic segments, as recommended by Catagni. Monofocal osteosynthesis with Ilizarov fixator for hypertrophic nonunions with minimal infection, as recommended by Catagni Monofocal osteosynthesis with Ilizarov fixator for hypertrophic nonunions with minimal infection, as recommended by Catagni

54. Ilizarov cont. Type IIIB open tibial fracture in 30-year-old man struck by automobile. Initial treatment was with four- pin anterior half-pin external fixator that was later converted to six-pin fixator; this fixator was removed because of persistent infection. B, One year after injury, infected nonunion with deformity. C, Shape of tibial deformity is duplicated by Ilizarov frame and is gradually corrected as nonunion is compressed. D, Union obtained at 4½ months. Type IIIB open tibial fracture in 30-year-old man struck by automobile. Initial treatment was with four- pin anterior half-pin external fixator that was later converted to six-pin fixator; this fixator was removed because of persistent infection. B, One year after injury, infected nonunion with deformity. C, Shape of tibial deformity is duplicated by Ilizarov frame and is gradually corrected as nonunion is compressed. D, Union obtained at 4½ months.

55. Nonunion cont. Factors complicating nonunion Infection Infection Poor tissue quality Poor tissue quality Short periarticular fragments Short periarticular fragments Significant deformity Significant deformity

56. Infection management Treatment of nonunion of tibia in which sequestration or gross infection is present. A, Bone is approached anteriorly and is saucerized, incision is closed, and infection is treated with antibiotics by irrigation and suction. B and C, Tibia is grafted posteriorly. B, Skin incision. C, Tibia and fibula have both been approached posterolaterally. Posterior aspect of tibia (or tibia and fibula) is roughened and grafted with autogenous iliac bone Treatment of nonunion of tibia in which sequestration or gross infection is present. A, Bone is approached anteriorly and is saucerized, incision is closed, and infection is treated with antibiotics by irrigation and suction. B and C, Tibia is grafted posteriorly. B, Skin incision. C, Tibia and fibula have both been approached posterolaterally. Posterior aspect of tibia (or tibia and fibula) is roughened and grafted with autogenous iliac bone

58. Nonunion cont. Specific Bones Management: Metatarsals Metatarsals Tibia Tibia Fibula Fibula Patella Patella Femur Femur Pelvis and acetabulum Pelvis and acetabulum Clavicle Clavicle Humerus Humerus Radius Radius Ulna Ulna

59. Tibia Medial Malleolus Medial Malleolus One month after intraosseous graft for nonunion of fracture of medial malleolus. B, Failure of grafting procedure. Medial malleolus was resected. C, Seven years after resection, ankle is stable, although mild arthritic changes are becoming evident. This is maximal amount of medial malleolus that can be removed if stability of ankle is to be preserved. One month after intraosseous graft for nonunion of fracture of medial malleolus. B, Failure of grafting procedure. Medial malleolus was resected. C, Seven years after resection, ankle is stable, although mild arthritic changes are becoming evident. This is maximal amount of medial malleolus that can be removed if stability of ankle is to be preserved.

60. Tibia cont. Technique for grafting nonunion of medial malleolus

61. Tibia cont. Medial malleolus Sliding graft Medial malleolus Sliding graft

62. Tibia cont. T.Shaft A, Nonunion after osteotomy. Failure to produce union by sliding inlay graft; fibula is intact. B, Four years after application of dual onlay grafts and osteotomy of fibula. Note that fibula overlaps T.Shaft A, Nonunion after osteotomy. Failure to produce union by sliding inlay graft; fibula is intact. B, Four years after application of dual onlay grafts and osteotomy of fibula. Note that fibula overlaps

63. Tibia cont. Oblique comminuted fracture of proximal third of tibia with fracture of tibial plateau. B, Satisfactory restoration of fragments. C, Fracture of shaft failed to unite; treated by dual onlay graft. Oblique comminuted fracture of proximal third of tibia with fracture of tibial plateau. B, Satisfactory restoration of fragments. C, Fracture of shaft failed to unite; treated by dual onlay graft.

64. Tibia cont. Patient with open tibial fracture treated initially with unreamed nailing. A, Broken distal screw indicated nonunion despite dynamization. B, Union achieved after exchanging nail Patient with open tibial fracture treated initially with unreamed nailing. A, Broken distal screw indicated nonunion despite dynamization. B, Union achieved after exchanging nail

65. Femur (supracondylar) Deformity and nonunion 7 years after supracondylar femoral fracture in 35-year-old woman; knee joint is ankylosed. B and C, Application of Ilizarov external fixator for correction of length and offset deformity. D and E, Union at 10 months. Deformity and nonunion 7 years after supracondylar femoral fracture in 35-year-old woman; knee joint is ankylosed. B and C, Application of Ilizarov external fixator for correction of length and offset deformity. D and E, Union at 10 months.

66. Femoral shaft A and B, Femoral defect in 16-year-old boy; type IIIB injury was sustained in hunting accident. C and D, Six months after medullary bone graft and fixation with static-locked, unreamed, intramedullary nailing A and B, Femoral defect in 16-year-old boy; type IIIB injury was sustained in hunting accident. C and D, Six months after medullary bone graft and fixation with static-locked, unreamed, intramedullary nailing

67. Clavicle Hypervascular nonunion of clavicle. A, Appearance 1½ years after fracture. Nonunion painful after recent fall. B, Solid union 2½ months after compression plating and bone grafting Hypervascular nonunion of clavicle. A, Appearance 1½ years after fracture. Nonunion painful after recent fall. B, Solid union 2½ months after compression plating and bone grafting

68. Humerus Combination tension band and buttress plate technique for nonunion of proximal humerus, as described by Healy, Jupiter, Kristiansen, and White. Heavy nonabsorbable suture is woven through rotator cuff using Krackow stitch and is fixed to T-plate to reduce pull of rotator cuff on proximal fragment and avoid pullout of proximal metaphyseal screws Combination tension band and buttress plate technique for nonunion of proximal humerus, as described by Healy, Jupiter, Kristiansen, and White. Heavy nonabsorbable suture is woven through rotator cuff using Krackow stitch and is fixed to T-plate to reduce pull of rotator cuff on proximal fragment and avoid pullout of proximal metaphyseal screws

69. Humerus Ununited fracture-dislocation with fracture at anatomical neck of humerus. A, Appearance on admission; four-part fracture with dislocation. B, Solid union 6 months after fixation with Neer I prosthesis. Function was satisfactory. Ununited fracture-dislocation with fracture at anatomical neck of humerus. A, Appearance on admission; four-part fracture with dislocation. B, Solid union 6 months after fixation with Neer I prosthesis. Function was satisfactory.

70. Humeral shaft Nonunion of middle third of humeral shaft. A, Nonunion with angulation and osteoporosis. B, Solid union 5 months after open reduction, fixation with nine-hole compression plate, and application of iliac bone grafts. Nonunion of middle third of humeral shaft. A, Nonunion with angulation and osteoporosis. B, Solid union 5 months after open reduction, fixation with nine-hole compression plate, and application of iliac bone grafts.

71. Humeral shaft Humeral nonunion. B, After fixation with intramedullary nail. Humeral nonunion. B, After fixation with intramedullary nail.

72. Humerus cont. Large defect in distal metaphysis of humerus after open fracture with separation of large segment of bone. B, Twenty months after bridging of defect by whole fibular transplant. Cancellous bone was used to bridge expanded portion of metaphysis and shaft. Large defect in distal metaphysis of humerus after open fracture with separation of large segment of bone. B, Twenty months after bridging of defect by whole fibular transplant. Cancellous bone was used to bridge expanded portion of metaphysis and shaft.

73. Humeral condyle Old fracture of lateral condyle of humerus in childhood. Marked cubitus valgus and nonunion are present. B, Immediately after reconstruction. C, Twelve months later normal range of flexion and extension is restored, with normal carrying angle, 50% supination and pronation, and fair stability despite degenerative changes. Old fracture of lateral condyle of humerus in childhood. Marked cubitus valgus and nonunion are present. B, Immediately after reconstruction. C, Twelve months later normal range of flexion and extension is restored, with normal carrying angle, 50% supination and pronation, and fair stability despite degenerative changes.

74. Monteggia’s Nonunion of ulna after radial head excision. Proximal ulnar fracture treated with locked forearm nail and tricortical iliac crest bone graft Nonunion of ulna after radial head excision. Proximal ulnar fracture treated with locked forearm nail and tricortical iliac crest bone graft