THE AMERICAN GERIATRICS SOCIETY Geriatrics Health Professionals.

1. FRACTURE FIXATION IN OSTEOPOROTIC BONEStephen Kates, MDHansjӧrg Wyss  Professor of Orthopaedic SurgeryDepartment of Orthopedics and RehabilitationAssociate Director, Center for Musculoskeletal ResearchUniversity of Rochester Medical CenterMichael BlauthNorbert SuhmJorg Goldhahn AGS THE AMERICAN GERIATRICS SOCIETY Geriatrics Health Professionals. Leading change. Improving care for older adults.

2. LEARNING OUTCOMES Understand the factors influencing fixation in cortical and trabecular bone affected with osteoporosis What implant characteristics help with fixation? What aspects of surgical fixation are important? Understand basic metabolic bone work-up

3. Definitions • Insufficiency fracture: bone fails with normal weight-bearing • Fragility fracture: result of a fall from a standing height or less

4. CONTENTS Osteoporotic cortical bone Biomechanical properties Choice of implants Surgical technique Trabecular bone Biomechanical properties Choice of implants Surgical technique

5. CONTENTS Osteoporotic cortical bone Biomechanical properties Choice of implants Surgical technique

6. BONE MASS CHANGESDURING LIFE Peak bone mass is reached at age 25 Heredity Medications Diet, tobacco, and alcohol Race / weight

7. CONTENTS Osteoporotic cortical bone Biomechanical properties Choice of implants Surgical technique

8. LOCKED-PLATE PRINCIPLE

9. PULLOUT OF REGULAR SCREWS by bending load

10. SHEARING CONVENTIONAL PLATE OR SCREW DOWN

11. RESISTANCE AGAINST BENDING LOAD

12. Resistance against bending load in locked plate Plate-screw connection is solid Screw-bone interface Fails as a unit

13. CONTENTS Osteoporotic cortical bone Biomechanical properties Choice of implants Surgical technique

14. UNI- VS. BICORTICAL SCREW FIXATION female

15. FAILURE WITH UNICORTICAL SCREWS Thin cortices: choose screw diameter as large as possible

16. 5 days later 10 months postop.

17. BIOMECHANICS: NORMAL BONE Load (N) +36% 600 +18% +6% 500 4.5 mm Cortex, bicortical 4.0 mm Locking, unicortical 4.0 mm Locking, bicortical 5.0 mm Locking, bicortical 400 300 200 100 0

18. BIOMECHANICS: OSTEOPENIC BONE Load (N) 600 +91% +82% 500 400 +17% 300 4.5 mm Cortex, bicortical 4.0 mm Locking, unicortical 4.0 mm Locking, bicortical 5.0 mm Locking, bicortical 200 100 0

19. BRIDGING WITH LOCKED IMPLANT

20. CONCEPTS OF PLATE FIXATION IN OSTEOPOROTIC BONE ? compression technique Bridge plating useful Neutralization plates useful Long plate for bone protection

21. CONTENTS Trabecular bone Biomechanical properties Choice of implants Surgical technique

22. OSTEOPOROSIS Normal bone Osteoporosis • In osteoporotic metaphyseal bone: • Fewer trabeculae for screws to engage • Loss of critical bony interconnections • Thinner internal support

23. SIGNS YOUR PATIENT HASPOOR-QUALITY BONE Poor dentition: teeth are formed similarly to bone Multiple vertebral compression fractures Previous hip, radius, or tibial plateau fracture End-stage renal disease On steroid therapy Anticonvulsant use

24. OSTEOPOROTIC TRABECULAR BONE:CLINICAL CONSEQUENCES Cut out Loss of screw fixation Spontaneous fractures

25. CONTENTS Trabecular bone Biomechanical properties Choice of implants Surgical technique

26. Flat surface, increased area Lag screw Less loss of bone with helical blade (right) Helical blade

27. CHOICE OF IMPLANT:ONE FIXED ANGLE VS. MANY Elderly woman who fell down one step One fixed angle with blade plate Multiple fixed angles, longer implant

28. VARUS COLLAPSE DUE TO LACK OF MEDIAL BUTTRESS

29. CONTENTS Trabecular bone Biomechanical properties Choice of implants Surgical technique

30. INTRA-OP IMPACTION

31. Augmentation to Improve Screw Fixation Enlarges the bone implant surface area NOT FDA APPROVED!

32. Augmentation in practice Slide 32

33. If bone is very poor, consider prosthetic replacement

34. DON’T FORGET THE SOFT TISSUES The wound must heal also Skin is also 98 years old Slide 34

35. Basic Osteoporosis Work-up: Metabolic • 25-OH vitamin D level • Intact PTH level • Calcium • Phosphate • TSH • Albumin level Slide 35

36. Radiologic Work-up OF OSTEOPOROSIS: DEXA Scan • DEXA is gold standard • T score is comparison to normal young bone • Z score is comparison to peers • Treat with fragility fracture and osteoporosis, osteopenia Slide 36

37. Vitamin D Repletion • Vitamin D2 50,000 units PO • Level 010 ng/dL: 3 times / week • Level 1120 ng/dL: 2 times/week • Level 2132 ng/dL: 1 time/week • For 612 weeks, then recheck level • Maintain with vitamin D3 1200 IU/day Slide 37

38. TreatmentsAfter Vitamin D repletion • For viable patients: • Bisphosphonates • Selective estrogen receptor modulators (SERMs) • Parathyroid hormone • Don’t forget the bone itself: treat the osteoporosis or refer Slide 38

39. TAKE-HOME MESSAGES Age & bone quality affect cortical and trabecular bone in different ways Absolute stability often not possible Principles of fixation: Angular stability Fracture reduction Long bridging plates Enlarged surface area of implant / bone Augmentation Prosthetic replacement

40. THANK YOU FOR YOUR TIME! Visit us at: www.americangeriatrics.org Facebook.com/AmericanGeriatricsSociety Twitter.com/AmerGeriatrics linkedin.com/company/american-geriatrics-society