1. Jwalant S. Mehta MS(Orth), D (Orth), MCh (Orth), FRCS (Tr & Orth) Consultant Spine Surgeon, ABMU Health Board SPONDYLOLISTHESIS

2. OUTLINE OF THE TALK ¤Classification ¤Natural history ¤Patho-physiology ¤Treatment rationale ¤Cases

3. SPONDYL OLISTHESIS 1741 Nicholas Andry: hollow back 1782 Herbiniaux Belgian obstetrician 1854 Kilian slow displacement ‘Spondylolisthesis’ 1855 Roberts: No slip if arch intact

4. CLASSIFICATIONS

5. Newman & Stone JBJS Br 1963; 45: 39 - 59

6. Type Name Description ICongenitalDysplastic abnormalities IIIsthmic ALytic (stress fracture) BHealed fracture (elongated, intact) CAcute high energy fracture IIIDegenerativeSegmental instability IVTraumaticFracture of hook other than pars VPathologicUnderlying pathology VIIatrogenicSurgical excision of posterior elements Wiltse, Newmann, MacNab Clin Orthop 1976

7. MEYERDINGS GRADES Low Grade High Grade I II III IV V

8. SLIP ANGLE Important in grades III – V

9. SPINO-PELVIC MEASURES

10. PELVIC INCIDENCE Pelvic tiltSacral slope PI = PT + SS

11. High PTLow SS Low PTHigh SS

12. RELEVANCE OF PELVIC MEASURES ¤PI quantifies the pelvic shape ¤Pelvic morphology and spino-pelvic balance are abnormal in spondylolisthesis

13. PATHO-PHYSIOLOGY

14. HOOK AND CATCH Hook: ¤Pedicle ¤Pars inter-articularis ¤Inferior process of the cephalad level Catch: ¤Superior process of the caudal level

15. PATHOPHYSIOLOGY ¤Dysplastic pathway ¤Traumatic pathway

16. Dysplastic pathway Traumatic pathway Weakness in the hook & catch mechanism Body weight transmitted through weak zone Soft tissue restraints: plastic deformation Growth plate overloaded Repetitive cyclic loads (sports) Stress fracture of a Normal pars Hard cortical pars pre- disposes to fatigue fracture and non-union Predisposes to a vertical subluxation

17. DYSPLASTIC CHANGES ¤Proximal sacral rounding ¤Trapezoidal L5 ¤Vertical sacrum ¤Junctional kyphosis ¤Compensatory hyper-lordosis Contributes to the mechanics of progression, but not causation

18. PROXIMAL SACRAL ROUNDING Yue Spine 2005

19. PROXIMAL SACRAL ROUNDING

20. DISCAL OVER-LOADING ¤Both the pathways lead to ↑ shear loads, axial loads remaining constant ¤Premature disc degeneration Alternative loading pathway Haher Spine 1994

21. ¤Chronic muscle spasm (protective):  ‘painful’ pars  Annular tears  Root compression / traction Leg pain is the most common symptom Moller Spine 2000 The pain generators: Back pain

22. THE PAIN GENERATORS: LEG PAIN ¤L5 compression / traction ¤Abnormal motion ¤Facet joint arthrosis ¤Pars scar ¤The disc above far-lateral

23. CLINICAL EVALUATION: HISTORY ¤Symptoms:  Back pain  Leg pain  Neurology ¤Severity ¤Activities of daily living

24. CLINICAL EVALUATION: EXAMINATION ¤Range and rhythm of trunk motion ¤Neurology ¤Sagittal alignment & gait

25. SAGITTAL ALIGNMENT ¤Stance ¤Gait ¤Head over pelvis ¤Hips and knees

26. IMAGING ¤Erect radiographs:  AP  Lateral (to include the hips) ¤MRI; CT ¤Occasionally: SPECT; Dynamic radiographs; Discography

27. PURPOSE OF IMAGING ¤Disc degeneration (MRI / CT) ¤Facet joint orientation, tropism, degeneration (MRI / CT) ¤Pelvic and spinal measures (Erect xrays)

28. DISC DEGENERATION

29. DISC DEGENERATION: MRI Pfirrmann et al Spine 2001 Grade I Grade IIGrade IIIGrade IVGrade V

30. FACET JOINTS

31. FACET JOINTS: ORIENTATION & TROPISM ¤Mean facet joint angle: Sagittal: anterior forces ¤Tropism R –L: asymmetric loads  Mild < 5°  Moderate 7° – 15°  Severe > 15° Vanharanta Spine 1993 Don JSDT 2008 Wang Spine 2009 Boden JBJS Am 1996

32. FACET DEGENERATION: CARTILAGE 1.Uniformly thick layer 2.Focal erosions 3.Areas of deficiency with exposed bone 4.Cartilage absent except traces Grogan et al AJNR 1997

33. FACET DEGENERATION: SUB-CHONDRAL SCLEROSIS 1.Thin layer of cortical bone 2.Focal thickening 3.Thick < ½ of the surface 4.Dense cortical bone > ½ of the surface Grogan et al AJNR 1997

34. FACET DEGENERATION: OSTEOPHYTES 1.No osteophyte 2.Small 3.Moderate 4.Large Grogan et al AJNR 1997

35. Severe Spinal Stenosis Centre for Spinal Studies and Surgery Nottingham

36. WILTSE CLASSIFICATION: III. DEGENERATIVE  Instability phase: Kirkaldy Willis  Posterior elements are intact  L45; F >M  Disc: ¤degeneration, ¤ ↓ height  Facets: ¤Tropism ¤Abnormal sagittal orientation ¤Facetal arthritis; subluxation

37. NATURAL HISTORY

38. NATURAL HISTORY: GENETICS ¤15 – 70% 1 st degree relatives ¤Lysis commoner in boys ¤Slips commoner in girls ¤Eskimos 25% (arch defects) Albanese JPO 1982 Wynne-Davies JBJS Br 1979 Roche JBJS Am 1952 Stewart JBJS Am 1953

39. NATURAL HISTORY: ‘THE SLIP’ ¤15% of persons with a pars lesion ¤During the growth spurt ¤Minimal change after 16 y ¤No pain during progression Bentley Spine 2003

40. EXTENT OF THE PROBLEM ¤Most are asymptomatic ¤90% slips at initial presentation do not progress Seitsalo JBJS Br 1990 Danielson Spine 1991 Frennerd JPO 1991 Seitsalo Spine 1991

41. PROGRESSION

42. PROGRESSION RISK ¤> 20 y: more stable, less symptomatic, less likely to progress ¤High level of athletic activity, no effect on progression ¤Association with back pain ‘weak’ Ohmori JBJS Br 1995 Muschik JPO 1996

43. RISK OF PROGRESSION: HIGHER LEVELS

44. THE RISK OF PROGRESSION IN THE YOUNG ADULT: DISC DEGENERATION

45. RISK FACTORS FOR SLIP PROGRESSION IN SPONDYOLISTHESIS (HENSINGER 1989) Clinical ¤Growth yrs (9 – 15) ¤Girls > Boys ¤Back pain ¤Postural or gait abn Radiographic ¤Type 1 (dysplastic) ¤Vertical sacrum ¤>50 % slip ¤Increasing slip angle ¤Instability on flex/ext views

46. RISK OF PROGRESSION: PROXIMAL SACRAL ROUNDING

47. TREATMENT RATIONALE

48. NATURAL HISTORY OF PROGRESSION ¤Adolescents III+: likely to progress ¤I, II after mid-adolescence: unlikely to progress

49. NON-OPERATIVE TREATMENT ¤Always consider first……………….everytime! ¤Improvement likely if back > leg pain ¤Isthmic / degnerative with leg pain: improvement less likely ¤Investigate / treat osteopaenia

50. NON-OPERATIVE TREATMENT: PAEDIATRIC ¤Stop aggravating activities ¤Gradual mobilisation ¤Trunk strengthening ¤Period of bracing

51. NON-OPERATIVE TREATMENT: ADULTS ¤Exercises ¤Aerobics ¤NSAID’S ¤Epidural steroids

52. MANAGEMENT DECISION ¤Individualized for each patient ¤Think of the natural history ¤Severity and duration of symptoms ¤Co-morbidities

53. SURGICAL INDICATIONS ¤Severe back and leg pain ¤Failed conservative trial ¤Abnormal neurology ¤+ve diagnostic injections

54. SURGICAL GOALS ¤Address the pars defect & the rattler ¤Decompress the foraminal stenosis ¤Address the degenerate disc/s ¤Address the dynamic instability

56. SURGICAL OPTIONS 1.In-situ postero-lateral fusion 2.Decompression + In-situ postero-lateral fusion 3.Additional inter-body fusion options

57. DECOMPRESSION: ABSOLUTE INDICATIONS ¤Neurology ¤Leg pain ¤Sphincter dysfunction ¤Claudication

58. DECOMPRESSION: EXTENT ¤The Gill procedure: Removal of the loose laminar arch ¤Foraminotomy + facetectomy ¤Never in isolation ¤Associated with ↑ pseudarthrosis rate Carragee JBJS Am 1997

59. IN-SITU POSTERO-LATERAL FUSION ¤L5 S1 only adequate ¤Improvement in leg pain even when not decompressed Burkus JBJS Am 1992 Frennerd Spine 1991 Ishikawa Spine 1994 deLobrresse Clin Orthop 1996

60. POSTERIOR INSTRUMENTATION ¤Better fusion rate, better clinical outcomes ¤Un-instrumented better for osteoporortic bones Moller Spine 2000 Zdeblick Spine 1993 Yuan Spine 1994 Bjarke Spine 2002 Deguchi J Spinal Dis 1998 Ricciardi Spine 1995

61. LEVELS TO INSTRUMENT ¤Look at the changes at the levels above ¤Higher slip angle: retro- listhesis above the slip

62. INTER-BODY FUSIONS: THEORETICAL CONSIDERATIONS ¤Anterior column support ¤Bio-mecahnically superior:  Large area for fusion  Grafts under compressive loads ¤Degenerate disc removed consider disc height ¤Build in the lordosis ¤Indirect reduction

63. INTER-BODY FUSIONS ( …… IF) P LIF T LIF A LIF

64. INDICATIONS FOR SURGERY: CHILDREN ¤Low grade slip / ‘lysis…..non op measures effective ¤Progression beyond Gr II ¤At presentation, > Gr III ¤Persisting pain; neurologic deficit ¤Progressive postural deformity / gait abnoralities

65. SURGERY: PAEDIATRIC / ADOLESCENT ¤‘ Lysis  Intact disc on MR (Gr I slip)  Direct repair of defect ¤Grade I  Asymptomatic….no surgery ¤Grade II, III  1 level bilateral lateral fusion  Rarely decompression  Documented progression; back pain

66. SURGERY: PAEDIATRIC / ADOLESCENT ¤Grade III+  Asymptomatic: 2 level in situ….L4 – S1  Slip angle < 55° good fusion rate Post op: Hyper-extension cast + thigh extension  Slip angle > 55° add anterior fusion Post-op: recumbent during healing ¤Severe slips  Excise body ( Gaines procedure)  L4 – S1 fusion

67. INDICATIONS FOR SURGERY: ADULTS ¤Non responsive to conservative measures ¤Results better for leg than for back pain ¤Isthmic / degenerative………persistent neurology; radicular symptoms ¤Back pain alone…….decompress & stabilise ( ↓ symptoms)

68. DEGENERATIVE SLIP ¤Caudal + facet injections ¤Decompress stenosis ¤Non-instrumented or instrumented fusion

69. ¤Think of the natural history ¤Look at each patient and analyse the problems ¤Individualize the treatment plan ¤If surgery is the last resort …………. RECOMMENDATIONS

70. ¤Choose surgical targets carefully ¤Ensure patient expectations match with your goals ¤In-situ PL fusion + decompression ¤Add inter-body in ‘high risk’ situations

71. CASES

72. PROGRESSION ON WAITING LIST

73. FLEXION EXTENSION X RAYS

74. RL

88. POST OP

89. CASE

100. RADIOLOGICAL RESULT Centre for Spinal Studies and Surgery Nottingham

101. CLINICAL RESULT Centre for Spinal Studies and Surgery Nottingham

102. CASE

103. Centre for Spinal Studies and Surgery Nottingham RADIOLOGICAL RESULT

104. Centre for Spinal Studies and Surgery Nottingham CLINICAL RESULT