Clinical results and functional outcomes of primary and revision spinal deformity surgery in adults.

BACKGROUND: Few studies have examined the postsurgical functional outcomes of adults with spinal deformities, and even fewer have focused on the functional results and complications among older adults who have undergone primary or revision surgery for spinal deformity. Our goal was to compare patient characteristics, surgical characteristics, duration of hospitalization, radiographic results, complications, and functional outcomes between adults forty years of age or older who had undergone primary surgery for spinal deformity and those who had undergone revision surgery for spinal deformity. METHODS: We retrospectively reviewed the cases of 167 consecutive patients forty years of age or older who had undergone surgery for spinal deformity performed by the senior author (K.M.K.) from January 2005 through June 2009 and who were followed for a minimum of two years. We divided the patients into two groups: primary surgery (fifty-nine patients) and revision surgery (108 patients). We compared the patient characteristics (number of levels arthrodesed, type of procedure, estimated blood loss, and total operative time), duration of hospitalization, radiographic results (preoperative, six-week postoperative, and most recent follow-up Cobb angle measurements for thoracic and lumbar curves, thoracic kyphosis, and lumbar lordosis), major and minor complications, and functional outcome scores (Scoliosis Research Society-22 Patient Questionnaire and Oswestry Disability Index). RESULTS: The groups were comparable with regard to most parameters. However, the revision group had more patients with sagittal plane imbalance and more frequently required pedicle subtraction osteotomies (p < 0.01). Patients in the primary group required more correction in the coronal plane than did patients in the revision group, whereas patients in the revision group required more correction in the sagittal plane. We found no significant difference between the two groups in the rate of major complications or in the Scoliosis Research Society-22 Patient Questionnaire functional outcome scores. There were significant improvements in many functional outcome scores in both groups between the preoperative and early (six-week) postoperative periods and between the early postoperative period and the time of final follow-up. CONCLUSIONS: Revision surgery for spinal deformity in adults, although technically challenging and considered to present a higher risk than primary surgery, was shown to have a complication rate and outcomes that were comparable with those of primary spinal deformity surgery in adults. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Prevalence of Allograft Contamination During Intraoperative Processing for Spinal Deformity Correction Surgery.

STUDY DESIGN: Prospective study. OBJECTIVES: To prospectively evaluate bone allografts during spinal fusion surgery for 1) the rate of contamination as a result of perioperative preparation, and 2) the types of bacterial organisms that may be transmitted through the contaminated bone allograft. SUMMARY OF BACKGROUND DATA: Bone allografts are routinely used to enhance spinal arthrodesis procedures. Ready availability and lack of donor site morbidity make them valuable alternatives to iliac crest bone grafts. Reports of disease transmission of such organisms as hepatitis C, the human immunodeficiency virus, and a variety of bacterial pathogens through allograft bone implants raise concerns for patient and practitioner safety. METHODS: Our study population consisted of 50 consecutive (20 male and 30 female) patients (mean age at surgery, 15 years; range, 3-51 years) undergoing spinal deformity correction from May 2010 through October 2010, by 1 surgeon at 1 institution. The mean operative time was 297 minutes (range, 81-444 minutes), and the most commonly fused spinal levels were T5 to L4. During the procedure, the researchers prospectively obtained intraoperative microbial culture swabs from a container with freeze-dried allograft and from an empty identical control container. Aerobic and anaerobic bacterial culture growth was assessed for 7 days postoperatively. Each patient was observed for 6 weeks after surgery to ascertain any evidence of surgical-site infection. RESULTS: Microbial cultures showed bacterial growth in 4 cases: 1 allograft specimen (day 4, very light Staphylococcus aureus) and 3 control specimens (day 3, very light Enterococcus; day 4, very light S aureus; and day 6, Propionibacterium acnes). No patient showed signs of infection in the perioperative or 6-week postoperative period. CONCLUSIONS: Intraoperative allograft preparation is not a major source of bone allograft contamination during spinal surgery.

Spinal deformity correction in Marfan syndrome versus adolescent idiopathic scoliosis: learning from the differences.

STUDY DESIGN: Retrospective case control study. OBJECTIVE: To compare patients with Marfan syndrome and matched patients with adolescent idiopathic scoliosis (AIS) to illustrate the differences and identify areas for potential surgical improvement. SUMMARY OF BACKGROUND DATA: Patients with Marfan syndrome commonly require spinal deformity surgery, but practice guidelines and results are not as established as those for patients with AIS. METHODS: We matched 34 adolescents with Marfan syndrome with patients with AIS (ratio, 1:2) for age, sex, and degree of major deformity. Overall mean age was 14 ± 2 years and mean curves were 51° thoracic and 46° lumbar. Mean follow-up was 5.3 and 3.6 years, respectively. RESULTS: The Marfan syndrome group had significantly more thoracolumbar kyphosis correction (9.5° vs. 0.1°, P = 0.05), significantly more levels fused (12 ± 2 vs. 9 ± 3, P ≤ 0.01), significantly more fusions to the pelvis (7 vs. 0, P = 0.01), and significantly more correction of sagittal imbalance (2.4 vs. -0.6 cm, P = 0.035). The Marfan syndrome group also had more intraoperative cerebrospinal fluid leaks (3 vs. 0, P = 0.01), significantly more instrumentation complications (3 vs. 1, P = 0.007), more reoperations for indications [such as fixation failure, distal degeneration, and spine fracture (9 vs. 0, P = 0.01)], and lower SRS-22 total (3.9 vs. 4.5, P = 0.01) and partial (P < 0.015) subscores. There were no significant differences between the groups in progression of unfused proximal thoracic curves, blood loss, neurological deficit, hospital stay, percent correction, or infection rate. CONCLUSION: Patients with Marfan syndrome differ in several ways from those with AIS: they require more levels of surgical correction, more distal fusion, greater correction of sagittal balance, and more reoperations, and they have more intraoperative cerebrospinal fluid leaks and instrumentation-related complications. Knowledge of these differences is important for planning surgery.

The role of arthrography in selecting an osteotomy for the correction of genu varum in pediatric patients with achondroplasia.

Genu varum is a common manifestation of achondroplasia. In the pediatric population, determination of the appropriate corrective osteotomy can be challenging because of a large cartilage envelope. To determine whether osteotomy based on radiographs alone corresponded to osteotomy based on arthrography and radiography, we retrospectively studied 41 patients (75 limbs) and identified the appropriate osteotomy based on (i) radiographs alone and (ii) radiographs and arthrography. We found that the osteotomy choice changed in 45 limbs (60.8%) overall and in 34 limbs (94.44%) of patients aged below 8 years.

Scoliosis in adults aged forty years and older: prevalence and relationship to age, race, and gender.

STUDY DESIGN: Retrospective study. OBJECTIVE: To identify the prevalence of lumbar scoliosis in adults ≥ 40 years old; to investigate relationships between scoliosis prevalence and 3 parameters (age, race, gender); and to determine any effect of those parameters on curve severity. SUMMARY OF BACKGROUND DATA: As the population ages, the incidence of degenerative spine conditions increases. More patients are being diagnosed with and treated for spinal deformities, including scoliosis. METHODS: We examined dual-energy x-ray absorptiometry lumbar spine images of 3185 individuals ≥ 40 years old (average, 60.8 years; range, 40-97 years), obtained July 2002 to June 2005, to determine the presence of scoliosis (i.e., a curvature of ≥ 11.0°) by digitally measuring Cobb angles. Patients with a history of previous lumbar spinal surgery were excluded, leaving 2973 individuals for final evaluation. We used SAS system software, version 9.1 (SAS Institute, Inc., Cary, NC) to investigate the relationship between the prevalence of scoliosis and the variables of age, race, and gender, we then examined for any effect that these variables had on curve severity. RESULTS: We identified scoliosis (i.e., a Cobb angle of ≥ 11°) in 263 of 2973 patients. Age was associated with an increased prevalence of scoliosis, e.g., 40 to 50 years old, 3.14%; ≥ 90 years old, 50%. Prevalence rates differed among races (e.g., 11.1% for whites and 6.5% for African Americans) but were similar for men and women. Most patients had mild curves (80.6%), there was no difference in the distribution of curve severity by gender or age, and African Americans were more likely to have mild curves (94.3%) than were other races. CONCLUSION: The prevalence of scoliosis in our patients ≥ 40 years old was 8.85% and was associated with age and race, but not with gender. Most curves in our population were mild; curve severity was associated with race but not with age or gender.