Mechanical Complications in Adult Spine Deformity Surgery: Retrospective Evaluation of Incidence, Clinical Impact and Risk Factors in a Single-Center Large Series

The advancement of deformity-specific implants and surgical techniques has improved the surgical treatment of Adult Spine Deformity (ASD), allowing surgeons to treat more complex deformities. Simultaneously, high rates of medical and surgical complications have been reported. The aim of this study is to describe the risk factors, the rate and the clinical impact of mechanical complications in ASD surgery. A retrospective review of a large, single-center database of consecutive ASD patients was conducted. Inclusion criteria were as follows: Cobb coronal curve > 20° or alteration of at least one of sagittal vertical axis (SVA > 40 mm), thoracic kyphosis (TK > 60°), pelvic tilt (PT > 20°) and pelvic incidence minus lumbar lordosis mismatch (PI-LL > 10°), at least four levels of posterior instrumented fusion and 2-year follow-up. At the baseline and at each follow-up end point, the authors collected clinical and radiographic outcomes and recorded any mechanical complications that occurred. One hundred and two patients were enrolled. Clinical outcomes significantly were improved at the last follow-up (mean 40.9 months). Postoperative mechanical complications occurred in 15 patients (14.7%); proximal junctional disease was the most common complication (60%) and the revision rate was 53.3%. Patients who experienced mechanical complications were older (61.2 vs. 54.8 years, p = 0.04); they had also a higher rate of pelvic fusion and posterior-only approach, a lower LL (−37.9 vs. −46.2, p = 0.02) and a higher PT (26.3 vs. 19.8, p = 0.009), TK (41.8 vs. 35.7, p = 0.05), PI–LL (12.9 vs. 5.4, p = 0.03) and Global Alignment and Proportion score (6.9 vs. 4.3, p = 0.01). This study showed a significant improvement in pain and disability after ASD surgery. Regarding the risk of developing a mechanical complication, not only postoperative radiographic parameters affected the risk but also patient age and surgical features

Effect of Body Mass Index Percentile on Clinical and Radiographic Outcome and Risk of Complications after Posterior Instrumented Fusion for Adolescent Idiopathic Scoliosis: A Retrospective Cohort Study

Background: The aim of this study is to evaluate the effect of body mass index percentile (BMI%) at postoperative and medium follow-up in AIS patients undergoing posterior instrumented fusion (PSF). Methods: We analyzed 87 clinical records of patients (19 male, 68 female) who underwent PSF. The patients were divided into four groups considering BMI%: underweight (UW), normal weight (NW), overweight (OW), and obesity (OB). Demographic, clinical (SRS-22), and radiographic data were collected. The primary outcome was to assess both the surgical and clinical outcomes, whilst the secondary outcome was to compare the radiological findings among the studied groups. Follow-ups were set preoperatively, at 6 months and 5 years. Results: Our results did not show significant differences of clinical outcomes among the studied groups, except for a longer surgical time and a higher hemoglobin decrease in UW and OB patients (p = 0.007). All BMI categories showed similar radiographic outcomes, with no statistical significance at final follow-up. OB patients showed a worse percentage of major curve correction compared to baseline and to UW and OW patients. Conclusions: The present study does not underline substantial differences in clinical and radiographic results among any of the studied groups. However, UW and OB patients showed a worse postoperative progress. Counseling should be provided for patients and families and the achievement of a normal BMI% should be recommended

Long-term results of pediculo-body fixation and posterolateral fusion for lumbar spondylolisthesis

Grob et al. (Eur Spine J 5:281–285, 1996) illustrated a new fixation technique in inveterate cases of grade 2–3 spondylolisthesis (degenerative or spondylolytic): a fusion without reduction of the spondylolisthesis. Fixation of the segment was achieved by two cancellous bone screws inserted bilaterally through the pedicles of the lower vertebra into the body of the upper slipped vertebra. Since 1998 we have been using this technique according to the authors’ indications: symptomatic spondylolisthesis with at least 25% anterior slippage and advanced disc degeneration. Afterwards this technique was used also in spondylolisthesis with low reduction of the disc height and slippage less than 25%. In every case we performed postero-lateral fusion and fixation with two AO 6.5 Ø thread 16 mm cancellous screws. From 1998 to 2002 we performed 62 fusions for spondylolisthesis with this technique: 28 males (45.16%) and 34 females (54.84%), mean age 45 years (14–72 years). The slipped vertebra was L5 in 57 cases (92%), L4 in 2 cases (3.2%), L3 in 1 case (1.6%), combined L4 and L5 in 2 cases (3.2%). In all cases there was an ontogenetic spondylolisthesis with lysis. Lumbar pain was present in 22 patients and lumbar-radicular pain was present in 40 patients. The mean preoperative VAS was 6.2 (range 5–8) for lumbar pain, and 5.5 (range 4–7) for leg pain. The fusion area was L5–S1 in 53 cases (85.5%), L3–L4 in 1 case (1.6%), L4–S1 in 8 cases (12.9%). A decompression of the spinal canal by laminectomy was performed in 33 procedures (53%). When possible a bone graft was done from the removed neural arc, and from the posterior iliac crest in the other cases. The mean blood loss was about 254 ml (100–1,000). The mean operative time was 75 min (range 60–90). The results obtained by computerized analysis at follow-up at least 5 years after surgery showed a significant improvement in preoperative symptoms. The patients were asymptomatic in 52 cases (83.9%); strained-back pain was present in 8 cases (12.9%), and there was persistent lumbar-radicular pain in 2 cases (3.2%). The mean ODI score was 2.6%, the mean VAS back pain was 1.3, the mean VAS leg pain 0.7. Some complications were observed: a nerve root compression by a screw invasion of intervertebral foramen, resolved by screw removal; an iliac artery compression by a lateral exit screw from pediculo, resolved by screw removal; a deep iliac vein phlebitis with thrombosis caused by external compression due to a wrong intraoperative position, treated by medicine. Two cases of synthesis mobilization and two cases of broken screws was detected. No cases of pseudoarthrosis and immediate or late superficial or deep infection were observed. The analysis of the long-term results of the spondylolisthesis surgical treatment with direct pediculo-body screw fixation and postero-lateral fusion gave a very satisfactory response. The technique is reliable in allowing an optimal primary stability, creating the best biomechanical conditions to obtain a solid fusion

Higher risk of dural tears and recurrent herniation with lumbar micro-endoscopic discectomy

Existing studies on micro-endoscopic lumbar discectomy report similar outcomes to those of open and microdiscectomy and conflicting results on complications. We designed a randomised controlled trial to investigate the hypothesis of different outcomes and complications obtainable with the three techniques. 240 patients aged 18–65 years affected by posterior lumbar disc herniation and symptoms lasting over 6 weeks of conservative management were randomised to micro-endoscopic (group 1), micro (group 2) or open (group 3) discectomy. Exclusion criteria were less than 6 weeks of pain duration, cauda equina compromise, foraminal or extra-foraminal herniations, spinal stenosis, malignancy, previous spinal surgery, spinal deformity, concurrent infection and rheumatic disease. Surgery and follow-up were made at a single Institution. A biomedical researcher independently collected and reviewed the data. ODI, back and leg VAS and SF-36 were the outcome measures used preoperatively, postoperatively and at 6-, 12- and 24-month follow-up. 212/240 (91%) patients completed the 24-month follow-up period. VAS back and leg, ODI and SF36 scores showed clinically and statistically significant improvements within groups without significant difference among groups throughout follow-up. Dural tears, root injuries and recurrent herniations were significantly more common in group 1. Wound infections were similar in group 2 and 3, but did not affect patients in group 1. Overall costs were significantly higher in group 1 and lower in group 3. In conclusion, outcome measures are equivalent 2 years following lumbar discectomy with micro-endoscopy, microscopy or open technique, but severe complications are more likely and costs higher with micro-endoscopy