Early and Late Complications Associated With Spinal Deformity Correction In The Ageing Patient

The precise risks of spinal deformity correction in older patients are poorly defined. The aim of this study was to report the early (<6MONTHS ) and late (>6months) complication rates associated with anteroposterior spinal deformity surgery in 56 consecutive patients > 60 years of age. A retrospective review of case notes was performed. Early complications were categorized as minor or major and influencing variables such as age, ASA grade, pulmonary function, staged surgery, surgical approach, number of levels, operative time, blood loss, and transfusion requirements were analyzed. The rate and type of late complications (>6months) were also determined. Statistical analysis was performed using Pearson correlation, Mann-Whitney Rank Sum and Chi-square tests.Patients averaged 66.3 years (60 - 78) old, 50 were female. Same day surgery was performed in 38 patients, 18 were staged, and 22 were revision cases. 19 patients were ASA 1, 28 ASA 2 and 9 ASA 3. Operative time and number of levels averaged 8.2 hours (5.5- 13) and 17(5-27), respectively. EBL averaged 3.35L (0.8-10) with intraoperative transfusion averaging 3.86 units (1- 10). Patients required hospitalization for a mean of 21.2 days (7-106).46(82%) patients had 112 early complications. There were no deaths. Major complications occurred in 50% of patients while 66% had minor. All except 3 occurred within 1 month of surgery. Medical complications totaled 76. Pneumonia occurred in 15(27%) patients, respiratory failure requiring ventilation in 6(10.7%), cardiac events in 7(12.5%), pulmonary embolus in 4(7%), DVT in 2(3.6%), and miscellaneous in 20(35%). There were 36 surgical complications: deep infection in 7(12.5%), superficial infection in 6(10.7%), neurological deficit 7(12.5%): foot-drop(4, recovery in 2), monoplegia(1, partial resolution), paraparesis(1, resolved), paraplegia (1, onset 24 hrs post-op, permanent). Implant complications (loss of fixation or malposition) occurred in 11(19.6%) cases. Intraoperative complications occurred in 7(12.5%) patients. Re-operation was required in 16(28.6%) patients within 6 months related to infection or implant complications. Increasing age and number of levels influenced the minor complication rate (p=0.026,r=0.299 and p=0.03,r=0.29 respectively), but not the major. ASA grade >1 was associated with an increase in major complications (p=0.02,r=0.32). FVC and FEV1 were inversely related to the major complication rate (r=-0.349,p<0 .001 and p="0.002.r=-0.44)." All patients with % predicted FEV1 <65% had a respiratory complication. Operative time, surgical approach, revision surgery, blood loss, transfusion requirements, staged Vs same day did not affect complication rate. Occurrence of complications increased hospital stay significantly (p<0.001). Late (>6months postop) complications occurred in 14 of 31 (45%) patients that were followed to at least 2 years. These included deep infection (2), pseudoarthrosis (4), loss of fixation with junctional kyphosis (2), painful instrumentation (4), and hernia (2). Anteroposterior spinal deformity surgery in patients of this age is associated with a high complication rate and a high early re-operation rate. Pre-existing medical condition and pulmonary function had the strongest impact on major complication rate. The late complication rate was also significant.In conclusion, surgical treatment of spinal deformity in older patients carries considerable risks and should not be undertaken without due consideration by both surgeon and patient alike.