Anna McClung

Serial casting as a delay tactic in the treatment of moderate-to-severe early-onset scoliosis.

Background: Serial casting can cure mild infantile idiopathic scoliosis. Its use in delaying surgery in older children and those with larger curves or syndromes is poorly defined. Methods: A review of a single center’s experience with casting was performed. Patients were included if they had a syndromic, neuromuscular, or congenital scoliosis or were older than 2.5 years with an idiopathic scoliosis measuring >50 degrees. Results: A retrospective review was performed on 29 patients meeting all inclusion criteria. Of these, 12 were idiopathic and 17 were nonidiopathic curves. Average age at first cast was 4.4±2.1 years, and 3.0±1.8 cast changes were performed over 1.4±1.1 years. Patients were transitioned to a brace and followed up for 5.5 years (range, 2.2 to 11.4 y). The main thoracic Cobb angle before casting was 68.8±12.3 degrees, which corrected to 39.1±16.4 degrees in a cast. Cobb angle after cast removal was 60.9±18.4 degrees, which increased to 76.3±24.0 degrees at final follow-up. T1-T12 height increased to 1.1±2.6 cm during the treatment period (P=0.05). There were 5 minor complications. Fifteen patients (51.7%) required surgical treatment for their scoliosis at most recent follow-up and an additional 7 patients (24.1%) were delayed until a definitive anterior/posterior spinal fusion could be performed. Surgery was delayed 39±25 months from the first cast. Growing rods were required in 8 patients (27.6%). The patients who ultimately underwent surgical intervention (SG) were more likely to have a larger postcasting residual main thoracic Cobb angle than those who did not require surgery [NS; 69.5±14.6 degrees (SG) vs. 51.6±17.9 degrees (NS), P=0.007] and had a greater progression of their curves after cast removal [20.9±13.5 degrees (SG) vs. 9.4±11.0 degrees (NS), P=0.02]. Conclusions: Serial casting is a viable alternative to surgical growth sparing techniques in moderate-to-severe early-onset scoliosis and may help delay eventual surgical intervention. Although a cure cannot be expected, an average of 39 months of delay was achieved in this patient cohort and 72.4% have avoided growing spine surgery. Level of Evidence: Level IV, case series.

Postoperative Ketorolac Does Not Predispose to Pseudoarthrosis Following Posterior Spinal Fusion and Instrumentation for Adolescent Idiopathic Scoliosis

Study Design. A retrospective review comparing patients who had postoperative ketorolac and those who did not following posterior spinal fusion and instrumentation (PSFI) for adolescent idiopathic scoliosis (AIS). Objective. To analyze the effect of postoperative ketorolac on the incidence of pseudoarthrosis in postoperative AIS patients. Summary of Background Data. Ketorolac (Toradol, Roche Laboratories, Nutley, NJ) is a nonsteroidal antiinflammatory drug that is an effective adjunct to manage postoperative pain. It has been previously demonstrated to inhibit spinal fusion in adult patients undergoing a L4 to sacral fusion. To our knowledge, there are no large studies analyzing this effect following PSFI for AIS. Methods. An IRB-approved retrospective medical record review was performed from 1994 to 2000 of patients undergoing a PSFI for AIS at a single institution. Segmental spinal instrumentation (Texas Scottish Rite Hospital) and iliac crest bone graft were used in both groups. Demographic and operative data were recorded. Patients were divided into those who had postoperative ketorolac (K group) and those who did not (NK group). Patients who had a surgically confirmed pseudoarthrosis were identified and the K group and NK group were statistically compared. Results. There were 161 patients in the NK group and 158 in the K group. There were no differences with respect to age (14.4 vs. 14.2 years), gender (83.9% vs. 84.8% females), levels fused (9.8 vs. 9.7), or preoperative curve magnitude (57.9° vs. 58.9°). In the K group, the number of doses of ketorolac administered was 6.7 for an average of 26.7 mg for a duration of 46 hours after surgery. Patients in the K group were more likely to have Motrin (average 5.8 doses) compared with the NK group (average 0.7 doses) (P < 0.01). No patient in the K group had a history of cigarette smoking compared with 2 patients in the NK group, both of whom went on to solid arthrodesis. The overall incidence of pseudoarthrosis was 2.5% for all patients. There was no difference in the incidence of pseudoarthrosis comparing the K (1.9%) and the NK group (3.1%)(P = 0.7). When the single rod posterior implants were excluded, there was no difference between the K (0.7%) and NK groups (1.8%) (P = 0.58). Conclusion. Ketorolac does not increase the incidence of developing a pseudoarthrosis when used as an adjunct for postoperative analgesia following a PSFI for AIS using segmental spinal instrumentation and iliac crest bone graft. The differences seen here compared with adults may be due to the greater healing potential in these young patients. We recommend utilization of ketorolac after surgery to supplement pain management when necessary.

Clinical and radiographic results after implant removal in idiopathic scoliosis.

Study Design. Prospective radiographic and clinical analysis of patients with idiopathic scoliosis who had complete implant removal following posterior spinal fusion (PSF) at least 2 years previously. Objective. To evaluate the clinical and radiographic effect of implant removal after PSF for idiopathic scoliosis. Summary of Background Data. Occasionally, implants must be removed following instrumented PSF. Indications for removal include infection and late operative site pain. Previously, it has been thought that there was little morbidity associated with implant removal in the presence of a solid fusion. However, recent studies have reported loss of coronal correction after implant removal in patients who had a PSF for adolescent idiopathic scoliosis. Few long-term studies have assessed the clinical or radiographic results of complete implant removal after PSF. Methods. We identified 56 patients who had undergone PSF for idiopathic scoliosis and subsequently had complete removal of all instrumentation. None of these patients had a pseudarthrosis at the time of implant removal. After IRB approval, 43 of 56 (77%) patients returned for new standing posteroanterior and lateral spine radiographs and completion of an SRS-22 questionnaire. Results. For the 43 patients who had new radiographs and completed an SRS-22, the time from the original PSF to complete implant removal averaged 2.9 years (range, 7 months to 7.25 years). Twenty-two patients had implants removed because of infection, and 21 patients had implants removed secondary to pain. The average time from implant removal to completion of the most recent radiographs and SRS-22 questionnaire was 9.5 years (range, 3.2–17.9 years). Patients were considered to have had progression of deformity after implant removal if their Cobb angle measurements increased by more than 10°. Two patients had 11° to 20° of coronal plane progression of their main thoracic curve. No patient had more than 10° of coronal plane progression of a lumbar curve. Sagittal curve progression was identified more frequently. Nineteen patients had between an 11° and 20° increase in thoracic kyphosis, and 5 patients had >20° of thoracic kyphosis progression. Patients with >20° of thoracic kyphosis progression after implant removal had greater thoracic kyphosis before surgery and larger main thoracic and lumbar coronal curves at the time of implant removal. Progressive kyphosis did not correlate with: reason for implant removal, length of follow-up, or time from fusion to implant removal. Although total SRS-22 scores correlated inversely with increased thoracic kyphosis, this trend did not reach statistical significance. Conclusion. Implant removal after PSF for idiopathic scoliosis may be complicated by progression of deformity. Patients requiring implant removal should be appropriately counseled and monitored.

Spinal appearance questionnaire: factor analysis, scoring, reliability, and validity testing.

Study Design. Cross sectional. Objective. This study presents the factor analysis of the Spinal Appearance Questionnaire (SAQ) and its psychometric properties. Summary of Background Data. Although the SAQ has been administered to a large sample of patients with adolescent idiopathic scoliosis (AIS) treated surgically, its psychometric properties have not been fully evaluated. This study presents the factor analysis and scoring of the SAQ and evaluates its psychometric properties. Methods. The SAQ and the Scoliosis Research Society-22 (SRS-22) were administered to AIS patients who were being observed, braced or scheduled for surgery. Standard demographic data and radiographic measures including Lenke type and curve magnitude were also collected. Results. Of the 1802 patients, 83% were female; with a mean age of 14.8 years and mean initial Cobb angle of 55.8° (range, 0°–123°). From the 32 items of the SAQ, 15 loaded on two factors with consistent and significant correlations across all Lenke types. There is an Appearance (items 1–10) and an Expectations factor (items 12–15). Responses are summed giving a range of 5 to 50 for the Appearance domain and 5 to 20 for the Expectations domain. The Cronbachs &agr; was 0.88 for both domains and Total score with a test–retest reliability of 0.81 for Appearance and 0.91 for Expectations. Correlations with major curve magnitude were higher for the SAQ Appearance and SAQ Total scores compared to correlations between the SRS Appearance and SRS Total scores. The SAQ and SRS-22 Scores were statistically significantly different in patients who were scheduled for surgery compared to those who were observed or braced. Conclusion. The SAQ is a valid measure of self-image in patients with AIS with greater correlation to curve magnitude than SRS Appearance and Total score. It also discriminates between patients who require surgery from those who do not.

Morphometric Analysis of Neurocentral Synchondrosis Using Magnetic Resonance Imaging in the Normal Skeletally Immature Spine

Study Design. Morphometric analysis of the neurocentral synchondrosis (NCS) using magnetic resonance imaging in the normal infantile and juvenile patients. Objectives. To assess the developmental stages of the neurocentral synchondrosis (NCS) by determining the age at which closure of the NCS occurs at specific levels of the spine and to evaluate whether symmetric growth of the NCS occurs during the different developmental stages in normal immature spine. Summary of Background Data. The function and developmental stage of the NCS are controversial because of a lack of agreement on the exact age of closure. To date, most authors believe that the NCS is actively open at a very early age, but the reported age of closure of the NCS varies from age 3 to 16 years. This various closure age of the NCS has resulted in some confusion about the role of the NCS in the normal spinal growth or the development of spinal deformity. Methods. A total of 34 normal pediatric patients who had axial magnetic resonance images from first thoracic vertebra to fifth lumbar vertebra were assigned into following 3 groups: infantile group (n = 11), 0 to 3 years of age; juvenile-young group (n = 16), 4 to 7 years of age; and juvenile-old group (n = 7), 8 to 10 years of age. T2-weighted axial magnetic resonance images were used to analyze the NCS developmental stages using a custom 6-point scale (0: actively open with 0% closure; 5: 100% NCS closure). For the stage 0 closure NCS, the width and thickness of the NCS were measured. Results. The NCS was actively open without closure for all less than 4-year-old patients at all levels. The NCS had approximate 75% closure in the lumbar region at 4 years of age while the thoracic NCS remained nearly open. After 5 years of age, the middle-lower thoracic NCS began to close with closure rate less than 25%. At the 10 years of age, the NCS in the lumbar region had near 100% closure, whereas the thoracic NCS demonstrated approximate 50% closure. For the NCS without closure, the average width and thickness were 7.6 × 1.3 mm on the left and 7.9 × 1.3 mm on the right, which was not significantly different. For the NCS with closure, the left and right NCS closure rates were not significantly different. Conclusion. The NCS developmental stage is age- and vertebral level-dependent. The NCS closes from the lumbar and proximal thoracic spine to the middle-distal thoracic spine and times from very early juvenile to the adolescent. The NCS symmetry bilaterally occurred not only during the active open, but also the long closure period. The NCS symmetric open and/or closure may be important to maintain the normal spine alignment.

A Comparison of Three Methods of Pain Control for Posterior Spinal Fusions in Adolescent Idiopathic Scoliosis

Study Design. Retrospective cohort study. Objective. To compare the efficacy of patient-controlled analgesia (PCA) with morphine alone, a single preoperative intrathecal morphine injection and PCA (IT/PCA), and epidural catheter infusion without PCA (EPI) for postoperative pain control after posterior spinal fusion (PSF) and segmental spinal instrumentation (SSI) in adolescent idiopathic scoliosis (AIS). Summary of Background Data. Postoperative pain control after PSF and SSI in AIS can be managed in different ways. EPI provides for a longer period of pain relief but is reliant on the correct placement and maintenance of the catheter in the epidural space. A single preoperative intrathecal morphine injection also provides for long acting analgesia. No direct comparison of these 3 methods of postoperative pain control has been reported. Methods. An IRB-approved retrospective chart review was performed at 2 institutions from 1997 to 2005. The medical record was reviewed to determine pain scores after surgery at multiple time periods. The 3 groups were compared using Student t test and &khgr;2 and significance was defined as P < 0.05. Results. There was no statistical difference in the gender, age, magnitude of curve, or number of levels fused in the IT/PCA (N = 42), PCA (N = 41), or EPI (N = 55) groups. Postoperative pain scores were lowest in the IT/PCA group in the first 8 hours (P < 0.05) but the pain scores in the EPI group were then lower through 24 hours (P < 0.05). Total morphine use (mg/kg) was lower in the IT/PCA group compared with the PCA group at 12 hours and 24 hours (P = 0.0001). Return to solid food ingestion was quickest in the EPI group (2.0 days) followed by the IT/PCA (2.6 days) and PCA alone (3.2 days) (P < 0.002). Respiratory depression and transient neurologic change occurred most frequently in the EPI group (EPI 11/55 pts vs. 1/42 IT/PCA vs. 0/41 PCA P < 0.001). Pruritis was greatest in the epidural group (11/55 P < 0.05). There were no intraoperative somatosensory-evoked potential changes or permanent neurologic injury recorded in any group. Conclusion. An EPI controls postoperative pain for the longest period of time and allows for a quicker return to consumption of solid foods. However, a single preoperative intrathecal morphine injection controls the pain equally for the first 24 hours with less pruritis and with less adverse events thus requiring less nursing and physician intervention after PSF and SSI in AIS. All methods were safe with no neurologic injury recorded.

Surgical site infections after posterior spinal fusion for neuromuscular scoliosis: a thirty-year experience at a single institution.

BACKGROUND Surgical site infection is a serious complication of posterior spinal fusion for neuromuscular scoliosis, with a reported prevalence of 6% to 24%. A single-institution experience over a thirty-year period was reviewed to determine the prevalence of surgical site infection after posterior spinal fusion for neuromuscular scoliosis, and to identify patient and treatment-related risk factors. METHODS Our retrospective review included all patients treated with posterior spinal fusion (alone or in combination with an anterior procedure) for neuromuscular scoliosis from 1980 to 2009 and followed for a minimum of two years. Univariate and multivariate statistical analysis was performed to identify significant risk factors for occurrence of deep surgical site infection (p < 0.05). RESULTS The study included 428 patients with an average duration of follow-up of 4.9 years. The mean Cobb angle was 74.3°. Most (74%) were treated with posterior spinal fusion alone. Deep infection developed in forty-four patients (10.3%); 57% of the infections occurred within three months after the surgery and 73%, within twelve months. Nearly half (45%) of the infections were polymicrobial; 59% of the organisms were gram-positive and 41% were gram-negative. Implant removal was required in 58% of the patients. Surgical site infection was more frequent from 1980 to 1989 (20.3%) than it was from 1990 to 2009 (8.4%) (odds ratio [OR] = 2.8, p = 0.01 in univariate analysis). Surgical site infection was more common in patients with spina bifida (21.5%) than in those with other diagnoses (8.3%) (OR = 3.0, p = 0.001). Other patient factors associated with surgical site infection were a body mass index (BMI) of >25 kg/m(2) (OR = 2.4, p = 0.04) and incontinence (OR = 2.4, p = 0.009). Treatment factors associated with surgical site infection were inadequate prophylactic antibiotic dosing (cefazolin ≤ 20 mg/kg) (OR = 3.3, p = 0.0002), length of fusion (p = 0.002), pelvic fixation (OR = 2.4, p = 0.04), length of hospital stay (p = 0.005), and other complications (OR = 3.2, p = 0.0003). Drain output (p = 0.04) and lower hemoglobin levels (p = 0.008) were significantly associated with surgical site infection in patients with spina bifida, and drain use (superficial to the fascia) was protective in those without spina bifida (OR = 0.5, p = 0.046). CONCLUSIONS This study identified modifiable factors, especially antibiotic dosing and drain use, associated with surgical site infection in patients with neuromuscular scoliosis.

Spinal cord monitoring in patients with spinal deformity and neural axis abnormalities: a comparison with adolescent idiopathic scoliosis patients.

Study Design. A retrospective review of spinal cord monitoring (SCM) results of patients with neural axis abnormalities (NAA) as compared with a control group of adolescent idiopathic scoliosis (AIS) patients. Objective. To analyze SCM on a group of patients who had a NAA undergoing spinal deformity surgery. Summary of Background Data. To our knowledge, only 1 report in the literature has analyzed the accuracy and reliability of SCM in patients with NAA. Methods. Over a 10-year period, 41 patients with NAA had SCM while undergoing surgery for spinal deformity. These patients were retrospectively compared with a group of 136 AIS patients. Results. The average ages were similar (14.4 vs. 14.6 years), but there were more males (48.8% vs. 19.1%) and greater preoperative curve magnitude in the NAA group (65.9° vs. 59.8°) (P < 0.05). Good baseline values were achieved less often in the NAA group for somatosensory-evoked potentials (SSEP) (85.4% vs. 98.5%) and motor-evoked potentials (MEP) (82.6% vs. 100%) (P < 0.05). Significant deviations from baseline values were seen more often in the NAA group for SSEP (8.6% vs. 1.5%) and MEP (5.3% vs. 2.5%). There were no false negatives in either group. Conclusions. SCM in patients who have NAA can be more difficult to obtain than in AIS but results in few false positives and does not miss neurologic injury.

Comparison of Growing Rod Instrumentation Versus Serial Cast Treatment for Early-Onset Scoliosis

STUDY DESIGN A comparison of 2 methods of early-onset scoliosis treatment using radiographic measures and complication rates. OBJECTIVES To determine whether a delaying tactic (serial casting) has comparable efficacy to a surgical method (insertion of growing rod instrumentation [GRI]) in the initial phase of early-onset deformity management. SUMMARY OF BACKGROUND DATA Serial casts are used in experienced centers to delay operative management of curves of surgical magnitude (greater than 50°) in children up to age 6 years. METHODS A total of 27 casted patients from 3 institutions were matched with 27 patients from a multicenter database according to age (within 6 months of each other), curve magnitude (within 10° of each other), and diagnosis. Outcomes were compared according to major curve magnitude, spine length (T1-S1), duration and number of treatment encounters, and complications. RESULTS There was no difference in age (5.5 years) or initial curve magnitude (65°) between groups, which reflects the accuracy of the matching process. Six pairs of patients had neuromuscular diagnoses, 11 had idiopathic deformities, and 10 had syndromic scoliosis. Growing rod instrumentation patients had smaller curves (45.9° vs. 64.9°; p = .002) at follow-up, but there was no difference in absolute spine length (GRI = 32.0 cm; cast = 30.6 cm; p = .26), even though GRI patients had been under treatment for a longer duration (4.5 vs. 2.4 years; p < .0001) and had undergone a mean of 5.5 lengthenings compared with 4.0 casts. Growing rod instrumentation patients had a 44% complication rate, compared with 1 cast complication. Of 27 casted patients, 15 eventually had operative treatment after a mean delay of 1.7 years after casting. CONCLUSIONS Cast treatment is a valuable delaying tactic for younger children with early-onset scoliosis. Spine deformity is adequately controlled, spine length is not compromised, and surgical complications associated with early GRI treatment are avoided.

Prone Thoracoscopic Release Does Not Adversely Affect Pulmonary Function When Added to a Posterior Spinal Fusion for Severe Spine Deformity

Study Design. Prospective clinical study. Objective. To analyze the effect of adding a thoracoscopic release and fusion performed in the prone position with double lung ventilation to a posterior spinal fusion and instrumentation (PSFI) for severe idiopathic scoliosis. Summary of Background Data. A prone thoracoscopic anterior release (TAR) offers the advantages of a minimally invasive approach, without requiring repositioning for the PSFI, and has significantly less acute pulmonary complications since single lung ventilation is avoided. It is unclear whether prone thoracoscopy adversely affects pulmonary function tests (PFT) when added to a PSFI for severe deformity. Methods. A prospective consecutive series of patients from a single institution undergoing spinal deformity surgery were reviewed. Those patients who underwent prone TAR followed by PSFI were compared to patients who had PSFI alone. In addition, those patients who had a thoracoplasty and PSF (PSFI-T) were compared to those who had a TAR and PSFI with T. (PFTs were measured before surgery and 1, 3, 6 weeks, 3 and 6 months, and 1 year after surgery. Forced vital capacity (FVC) and FE-1 parameters were compared to baseline levels for each patient. Results. There were 13 patients in the TAR + PSFI groups and 83 in the PSFI groups. The patients in the TAR + PSFI group had larger thoracic curves (83.2° vs. 59.7°), greater correction (59.4% vs. 50.1%) (P = 0.07), and greater increase in thoracic height (16.4% vs. 6.8%) following surgery. (P < 0.05) PFTs declined more rapidly for the TAR + PSFI patients in the first 3 weeks, however, improved rapidly until 1 year when they were significantly better than the PSFI group for predicted FVC % (29.7% vs. 7.5% above baseline) and forced expiratory volume (FEV) 1% (28.5% and 8.9% above baseline). (P < 0.05) When a thoracoplasty was added to the procedure, the differences in PFTs between those who had a TAR and those who did not was not significant. The TAR + PSFI-T group had FVC % predicted of 5.3% above baseline compared to 4.3% above baseline for the PSFI-T group. The percent predicted FEV 1% was 10.4% above baseline for the TAR + PSFI-T group compared to 4.5% for the PSF-T group (P > 0.05). Conclusion. When performing a prone thoracoscopic release for severe thoracic deformity, excellent coronal plane correction is achieved. There does not appear to be any detrimental effect on pulmonary function when a prone thoracoscopic release using double lung ventilation is added to a PSFI. This technique can be efficacious in achieving excellent deformity correction without adversely affecting pulmonary function and is recommended when treating severe spinal deformity. Adding a thoracoplasty provided a negative effect on pulmonary function and limited the benefits of performing a thoracoscopic release to the PSFI patients.