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1、SURGICAL TREATMENT OF SPINE OSTEOPOROSIS,,Concept of Osteoporosis,A systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragili

2、ty and a susceptibility to fracture." the above definition developedin Hong Kong in 1993,Pathophysiology of OP,Bone RemodelingImbalance of bone remodeling, In pathologic situations, bone mass may be sacrificed

3、to satisfy the body's intra- and extracellular calcium needs.,,A specific quantity of bone is resorbed from the remodeling site and then a reversal occurs and the cavity is occupied by osteoblasts which refill that c

4、avity with bone,The Progression of Bone Remodeling,Mechanisms of Bone Loss,An increased number of bone remodeling units can be activated which, when combined with either of the above two processes, may result in increase

5、d bone loss.,bone loss is equal to bone formation and the amount of bone tissue present represents normal bone mass,increased number of remodeling sites increased porosity of the bone, ie the remodeling space, and this g

6、ives decreased bone mas,Bone Loss: Cancellous vs. Cortical Bone,Although cancellous bone may account for less than 25% of the total bone mass in healthy adults, its surface area far exceeds that of cortical bone.,Bone L

7、oss: Cancellous vs. Cortical Bone,Cancellous bone is more metabolically active than cortical bone. If bone remodeling becomes uncoupled, with osteoclastic activity exceeding osteoblastic activity, the mass and structura

8、l integrity of cancellous bone is more severely affected than cortical bone.,Bone Loss: Cancellous vs. Cortical Bone,During the accelerated period of bone loss occurring immediately post-menopause, cancellous bone loss i

9、s increased 3-fold, while rates of cortical bone loss are slower. Therefore, fractures related to osteoporosis most commonly occur in areas rich in cancellous bone (ie, the vertebrae and wrist), and BMD measurements hav

10、e focused on these critical anatomic sites,high turnover with either increased formation or increased resorption or both,,Patterns of Age-Related Bone Loss,Gradual bone loss begins in both men and women between the age 3

11、0 and 40, paralleling an age-related decline in muscle mass. menopause women begin a period of accelerated bone loss, averaging from 2%-5% per year over the next ten years.,Estrogen-Related Bone Loss,although high affin

12、ity estrogen receptors have been identified on both osteoclasts and osteoblasts.,Additionally, it is thought that estrogen deficiency is more directly associated with accelerated bone loss, but not age-related bone loss.

13、,,Accelerated Bone Loss,Accelerated bone loss is greatest in the first 3-6 yrs after menopause, levels off, and then gradually assumes the level of premenopausal bone loss.This period of accelerated bone loss, coupled w

14、ith the lower average BMD in women compared to men, explains the higher incidence of osteoporosis and osteoporotic fractures in women,Vertebrae and Cancellous Bone,The vertebrae have a high percentage of cancellous bone.

15、 Therefore, vertebral fractures are the most common fracture site in the early menopausal years;Hip fractures tend to occur in later life. The degree of bone loss may vary from site to site in the same individual.,Menop

16、ausal Bone Loss,Menopausal bone loss can vary among women from 2%-5% per year. Higher rates of bone loss have been classified as "fast" losers. It is thought that this category of women (about 5%-10% of all me

17、nopausal women) may be at higher risk for fractures;,NFO Recommendations for BMD Testing,All postmenopausal women under age 65 who have one or more additional risk factors for osteoporosis(besides menopause);All women a

18、ged 65 and older, regardless of additional risk factors;Postmenopausal women who present with fractures(to confirm diagnosis and determine disease severity);,NFO Recommendations for BMD Testing,Women who are considering

19、 therapy for osteoporosis, if the BMD testing facilitate the decision;Women on hormone replacement therapy for prolonged periods.,Issues in Bone Mineral Testing Considerations,A woman's willingness to be treated;C

20、ommitment to HRT therapy;Patient who is uncertain about HRT;Technology and anatomic site considerations;,Bone Mineral Density -- Defining Diagnostic Categories,Normal. BMD within 1 SD of the "young normal&quo

21、t; adult (T-score above -1).Low bone mass (osteopenia). BMD is between 1 and 2.5 SD below that of a "young normal" adult (T-score between -1 and -2.5).,Bone Mineral Density -- Defining Diagnostic Categor

22、ies,Osteoporosis. BMD is 2.5 SD or more below that of a "young normal" adult (T-score at or below -2.5). Women in this group who have already experienced one or more fractures are deemed to have severe or

23、 "established" osteoporosis.,Limitations of Diagnostic Criteria Based on T-Scores,The use of different young normal reference databases, different densitometric devices, that may result in different T-scores ot

24、her risk factors for fracture besides BMD and the intermediary nature of BMD.These vary depending on the instrument used to obtain the data,Other Risk Factors for Fracture,Nonmodifiable:Personal history of fracture as

25、an adult History of fracture in first-degree relative Race Advanced age Female sex Dementia Poor health/frailty,Other Risk Factors for Fracture,Potentially modifiable:Current cigarette smoking Low body weight/thi

26、nness (1 year),Other Risk Factors for Fracture,Potentially modifiable:Low calcium intake (lifelong) Alcoholism Impaired eyesight despite adequate correction Recurrent falls Inadequate physical activity Poor health/

27、frailty,WHO Definition Estimates,30% of all postmenopausal white women will be diagnosed with osteoporosis;54% will have low bone mass at the hip, spine or wrist. More than half the women with osteoporosis will have a

28、history of prior fracture of the proximal femur, spine, distal forearm, proximal humerus or pelvis.,Fractures Associated with OP,Vertebral FractureHip FractureDistal Forearm FractureOther Fractures Fracture of the

29、proximal humerus, pelvis, proximal tibia and distal femur.,Impact of Vertebral and Hip Fractures,Both fractures may be associated with significant morbidities and increased mortality as follows:About 1/2 the women with

30、hip fractures will spend some time in a nursing home.Only 1/3 of hip fracture patients regain their prefracture level of function, with many unable to walk independently or perform basic activities of daily living.,Impa

31、ct of Vertebral and Hip Fractures,20% of women who suffer a hip fracture will die in the following year as an indirect consequence of the fracture. A history of vertebral fracture is associated with an increased risk of

32、 a subsequent fragility fracture,Impact of Vertebral and Hip Fractures,Vertebral fracture may be associated with back pain, disability or physical deformity (eg, kyphosis, height loss, abdominal protrusion). In fact, th

33、e threat of physical deformity may be a powerful influence on a woman's commitment to therapy. Additionally, there is an increase in mortality related to frailty, comorbidities and an increased risk of pneumonia.,Ve

34、rtebroplastyand Kyphoplasty,A new technique of Minimal Invasive Spinal SurgeryCarry out in China from 2001,Vertebroplasty- Minimal Invasive Treatment of Compression Frx,,Vertebroplasty literally means fixi

35、ng the vertebral body. A metal needle is passed into the vertebral body and a cement mixture containing polymethylmethacrylate (PMMA), barium powder, tobramycin, and a solvent are injected under imaging guidance by the p

36、hysician.,Vertebroplasty- Minimal Invasive Treatment of Compression Fractures,,The cement hardens rapidly and buttresses the weakened bone. The barium makes the cement visible on x-ray and the tobramycin is an antibiotic

37、.,,,,,,,,,Risks of Procedure,1). Leakage of cement into veins and or lungs2). Infection 3). Bleeding4). Rib or Pedicle fracture 5). Pneumothorax 6). Worsened pain 7). Paralysis secondary to leakage of cement,What a

38、re indications for Vertebroplasty?,1). Painful compression fracture secondary to osteoporosis 2). Painful compression fracture secondary to tumor which does not respond to conventional therapy 3). Prevent further compr

39、ession fractures 4). Buttress weakened bone for spine fusions,Relative Contraindications,Young patient - the long term effects of the cement mixture are unknownVertebral bodies above the T5 level - the procedure is ris

40、kier and more difficultPatients with prior unsuccessful spine surgery,Patient Evaluation,1) History and Physical Examination 2) Current x-rays3) MRI +/- bone scan,Surgical Procedure of Vertebroplasty,be carried out i

41、n an operating room or in a special X-ray suite. A needle is placed in a vein so that the patient can get medication for sedation and pain. The patient lies prone with padding under the body and with the hips sli

42、ghtly bent. The arms are positioned above the shoulder.,Surgical Procedure of Vertebroplasty,2,A radiopaque (visible on X-ray) marker is placed on the patient over the vertebra to be injected. Positioning of the mar

43、ker is guided by fluoroscope (video-like X-ray machine). Clearly seeing the correct vertebra is more difficult in the severely osteoporotic patient,Surgical Procedure of Vertebroplasty,3,Local anesthetic; injected in

44、to the skin and along the path toward the pedicle of the vertebra to be injected. The needle is left in against the pedicle to mark the path of the special needle used for injecting the cement. The special needle i

45、s an 11-gauge bone biopsy needle. A small skin incision is made and bone biopsy needle inserted,Surgical Procedure of Vertebroplasty,4,The tip of the bone biopsy needle is stuck for about 1-2 mm into the pedicle. Po

46、sitioning of the this needle is continuously guided with the fluoroscope in both the anterior-posterior (AP, front to back) and lateral (side to side) views,Surgical Procedure of Vertebroplasty,5, Advance the bone biops

47、y needle to the front one-third of the vertebra. On the AP view the needle lies near the midline of the body of the vertebra. The needle is filled with saline to prevent air injection. A contrast solution that can be

48、 seen on X-ray is injected. Takes X-ray pictures during the injection to see how the contrast flows from the center of the vertebra into the local veins.,Surgical Procedure of Vertebroplasty,6, Prepare the plastic mat

49、erial to be injected. Mix the PMMA powder with tungsten powder or barium sulfate to make it visible on X-ray. Add the liquid to the powder and mixed to a thick yet pourable consistency similar to honey,Surgical Pr

50、ocedure of Vertebroplasty,7, Load the PMMA into several small syringes. The syringe is connected to the bone biopsy needle and injected under fluoroscopic guidance to be sure that the material does not run off into the

51、 veins. The PMMA hardens after injected to support the vertebra (Axial and sagittal animations),Complications,Complications occur inapproximately 3% of osteoporotic patientsapproximately 5% of patients with hemagioma

52、sapproximately 10% of patients with cancer to the vertebra,Complications,The most common complications are Rib fracture due to the downward on the back needed to insert the needle in the bony vertebraIrritation of an

53、 adjacent nerve rootThese complications usually resolve on their own in a few monthsPneumothorax (punctured lung),Complications,Pneumothorax (punctured lung) Fracture of the pediclePMMA pulmonary embolus - the PMMA e

54、nters the veins through the bone and is taken to the lungCompression of the spinal cord with paralysis or loss of feeling,Complications,Increased back painPMMA may go outside the bone into the soft tissuesWound Infec

55、tionPneumonia,Follow Up Care,Pain medications - usually tapered over several days after procedureMuscle relaxants Adjust medications to prevent further mineral loss,Vertebroplasty Statistics,>80% moderate to marke

56、d pain relief<5% induced fractures from procedure<1% symptomatic embolism or infection,,Experiences of Our Hospital,04. 2001 —08. 200358 patients,65 vertebra L1 16,L2 12 ,L3 7 , L4 5 T4 1, T8 2,T

57、9 4 ,T10 4 T11 6,T12 8.,Case 1 Female68yrs L1fracture before operationBack pain after falling on the ground,,Case 1 female 68yrs L1fracture postoperationTo walk at the first day after operation,,,,,Case 1

58、 female 68yrs L1fracture postoperation CT,Case 2,,Case3 T12CompressionVertebra FractureDuring operation,Case3 T12 CompressionVertebra FracturePost-operation,Case 4 Postoperation,,CASE 5.

59、 Female, 84 Y L2 Compression Vertebra FractureDuring operation,CASE 5. Female, 84 Y L2 CompressionVertebra FracturePostoperation,,CASE5. Female, 84 Y L2 CompressionVertebra FracturePostoperation,Case 6 72 yrs,

60、 Female.Compressive Frx,Cervical Spine Fractures and Osteoporosis,Fractures of the cervical spine usually result from major trauma (traffic accidents, falls from great heights or dives into shallow water). In elderly p

61、atients severe cervical spine injuries may already result from simple falls.little information available on treatment and outcome of cervical spine injuries in the elderly, especially regarding the subaxial spine,Cervic

62、al Spine Fractures and Osteoporosis,In the general population, about 50% of fractures involve the C5-6 and C6-7 level, with dens fractures being the second most frequent localization.The incidence of lower cervical spin

63、e injuries continuously declines with age.In contrast, the incidence of upper cervical spine injuries rises in the elderly.Fractures of the dens are the most common location in patients above theage of 70 years,Cervica

64、l Spine Fractures and Osteoporosis,,A 68-year-old patient, presenting with incomplete tetraplegia after falling from a tree.The lateral radiograph shows no apparent fracture, but there is advanced multilevel degeneratio

65、n,MRI confirms severe spinal canal stenosis, mainly at levels C4-5 to C6-7. The patient died a few days later due to pulmonary complications.,Cervical Spine Fractures and Osteoporosis,,A 62-year-old patient presenting w

66、ith cervical myelopathy 2 years after an initially missed dens fracture. MRI shows the pseudarthrosis and a bulging tissue mass posterior to the dens.,Cervical Spine Fractures and Osteoporosis,,Fractures of the Dens Axis

67、Own Material of Anterior Screw Fixation of Dens Fractures,Thoracic and Lumbar Spine Fractures,,,Indications for surgery: devastating neurological compromise orincreasingly unstable kyphosis at the fracture site.,Thora

68、cic and Lumbar Spine Fractures,,,Late Neurological Compromise after OsteoporoticFractures,Thoracic and Lumbar Spine Fractures,,,Posture and Approach,Thoracic and Lumbar Spine Fractures,,,Reconstructive Surgery ofOsteop

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