Implementation of Pre-operative Planning:

Transcription

1 Implementation of Pre-operative Planning: 1-Year Results Using Patient-Specific UNiD Rods in Adult Deformity C.J. Kleck, MD 06/16/2017

2 Pre-operative Planning In the fields of observation chance favors only the prepared mind -Louis Pasteur Pre-operative Planning has always been key

3 Pre-operative Planning 35 F T7 and T8 fractures with subsequent infection

4 Pre-operative Planning Ability to plan surgery PSF T2-L2 Baseline 3 11 SPOs, T7/8 43 Osteotomy Actual Rod Order Corpectomy T7 SPO T3-4, T4-5, T5-6, T9-10 Ability to order a rod representing the plan

5 Pre-operative Planning to Intra-operative Implementation Is that really going to work? What correction can you get? Would the rod contoured during surgery look the same?

6 Intra-operative Implementation

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9 Post-operative Evaluation Mapping of Parameters Baseline 3 11 SPOs, T7/8 43 Osteotomy Postop Actual Rod Order Simulation of operation Patient specific rod Compare pre to post Critically assess outcomes

10 Our First Pilot Study Patient Specific Rods vs Standard Spine rods Retrospective case review 32 total ASD patients treated with posterolateral spine fusion and osteotomy 16 consecutive patients treated with patient specific rods and 16 matched retrospective controls (standard spine rods). Controls were matched to cases based on specific criteria including gender, age group, diagnosis, and number of posterior fusion levels.

11 Data Points Intraoperative operative time estimated blood loss (EBL) postoperative spinopelvic parameters were compared among cases and controls. As this was a novel approach immediate postop outcomes assessed Patients were included with any length of follow-up as long as postoperative imaging was available.

12 Baseline Characteristics Characteristics Index Cases Controls Age Mean (St. D) 62 Y 62 Y Gender Female N (%) 9 (56.2) 9 (56.2) Male N (%) 7 (43.8) 7 (43.8) BMI Mean (St. D) ASA Mean (St. D) Primary N (%) 7 (44%) 5 (31%) Reoperation N (%) 9 (56%) 11 (69%) Number of Posterior Fusion Levels Mean (St. D) Lumbar Lordosis Mean degrees (St. D) Pelvic Tilt Mean degrees (St. D) Pelvic Incidence-Lumbar Lordosis (PI-LL) Mean degrees (St. D) Sagittal Vertical Axis (SVA) Mean mm (St. D) Thoracic Kyphosis (TK) Mean degrees (St. D)

13 Post op alignment case/control Characteristics Index Cases Controls Relative Risk P Value (X2) (95%CI;min;max) Postoperative Values Characteristics Index Cases Controls Relative Risk Operative Time (min) Mean (St. D) () () Blood Loss (ml) Mean (St. D) 2308 () 1719 () Packed Red Blood Cell Transfusion (ml) Mean (St. D) 519 () 415 () Cell Saver Transfusion (ml) Mean (St. D) 629 () 612 () Complications LL (degrees) Mean (St. D) PT (degrees) Mean (St. D) PI-LL (degrees) Mean (St. D) SVA (mm) Mean (St. D) 16.2mm 35.2 TK (degrees) Mean (St. D) Dural Tear N (%) 4 (25%) 3 (19%) Meeting Adequate Alignment Thresholds (95%CI;min;max) PI-LL <10 degrees N (%) 16 (100%) 12 (75%) 0.13 SVA <40mm N (%) 11 (69%) 7 (44%) 0.56 (0.24; 1.29) 0.17 Age adjusted targets* N (%) 13 (81%) 10 (63%) 0.50 (0.15; 1.66) 0.26 P Value (X2)

14 Patient Specific Spine Rods for Adult Spinal Deformity. Results Characteristic Preoperative Mean (SD) Planned Mean (SD) Postoperative Mean (SD) Difference Postop.-Preop. Postop.-Planned Mean P Mean P Sagittal vertical axis (SVA), mm < Thoracic kyphosis (TK), degree <0.001 Lumbar lordosis (LL), degree < Pelvic incidence (PI), degree PI-LL mismatch, degree < Sacral slope (SS), degree < Pelvic Tilt (PT), degree <

15 Conclusions The implementation of a surgical plan using patient specific spine rods appears to be an effective method for correction of severe adult spine deformity. This method allowed the planned (age-adjusted) postoperative sagittal balance to be reached in (81%) vs (63%) of the controls. PI-LL <10 degrees: 100% of cases vs. 75% of controls (p<0.13) The pelvic tilt and sacral slope were less predictive after long lumbar fusion with osteotomy. Likely, their impact on sagittal balance was indirect through PI.

16 Subsequent Analysis 55 Patients from 11/ /2016 PI-LL SVA

17 Subsequent Analysis 55 Patients from 11/ /2016 PT TK

18 Paradigm shift Previously we contoured the rod to the patient Relying on software and pre operative measurements is not unfamiliar to the orthopedic surgeon but often the correction depended on the art more than the science. Trust the planning and contour the patient to the rod

19 Case 1

20 Case 1 Correcting the Patient to the Rod

21 Case 1

22 Case 2

23 Case 2

24 Case 2

25 Case 3

26 Case 3

27 Thank You! To date we have implanted more than 70 pre contoured rods, with our first 2 year follow up results in November We have seen less rod fracture and less PJK and are anxiously following our patients.

28 References 1.Good CR, Auerbach JD, O Leary PT, Schuler TC (2011) Adult spine deformity. Curr Rev Musculoskelet Med 4: doi: /s z 2. Roussouly, Pierre (02/01/2005). "Classification of the normal variation in the sagittal alignment of the human lumbar spine and pelvis in the standing position". Spine (Philadelphia, Pa. 1976) ( ), 30 (3), p Schwab, Frank (12/01/2006). "Gravity line analysis in adult volunteers: age-related correlation with spinal parameters, pelvic parameters, and foot position". Spine (Philadelphia, Pa. 1976) ( ), 31 (25), p. E Vialle, Raphaël (02/2005). "Radiographic analysis of the sagittal alignment and balance of the spine in asymptomatic subjects". Journal of bone and joint surgery. American volume ( ), 87(2), p Lafage, Virginie (08/01/2009). "Pelvic tilt and truncal inclination: two key radiographic parameters in the setting of adults with spinal deformity". Spine (Philadelphia, Pa. 1976) ( ), 34 (17), p.e Lafage, Virginie. "Spino-pelvic parameters after surgery can be predicted: a preliminary formula and validation of standing alignment". Spine (Philadelphia, Pa. 1976) ( ), 36 (13), p Gill JB, Levin A, Burd T, Longley M. Corrective Osteotomies in Spine Surgery. J Bone Joint Surg Am. 2008;90: Bridwell KH, Lewis SJ, Lenke LG, Baldus C, Blanke K. Pedicle Subtraction Osteotomy for the Treatment of Fixed Sagittal Imbalance. J Bone Joint Surg Am. 2003