Assessment of the correlation between clinical and radiological outcomes in patients suffering from mild to moderate cervical spine dysfunction symptoms: a prospective study.

BACKGROUND: Neck pain and cervical disc degeneration (CDD) are common findings. Valid data on correlation between clinical scores and radiological grade of CDD in patients with mild to moderate clinical disability are not available. The study has been designed to investigate the correlation between clinical and radiological outcomes in these patients. METHODS: A cohort of 150 patients who suffered from mild to moderate cervical spine dysfunction symptoms from September 2020 to May 2021 was enrolled. We evaluated functional status using Japanese Orthopaedic Association scores (JOA), the visual analog scale, and the Neck Disability Index. We assessed the CDD with magnetic resonance imaging-based grading systems. We analyzed relationships between radiological grades of CDD and clinical symptoms along with demographic data. RESULTS: One hundred thirteen patients [mean age 44.78, 78 (69%) females] were finally included. CDD occurred most at the C5-C6 level, with 56.93% of higher grade III from Miyazaki. The grades of Miyazaki (P < 0.05) and the scores of Nakashima (P < 0.05) were positively correlated with the duration of symptoms, and the severity of the CDD increased with aging (P < 0.01). Moreover, we correlated patients' JOA scores with the current scoring and grading systems, especially the grades of Miyazaki (P < 0.01) and the scores of Nakashima (P < 0.01). CONCLUSION: Increasing grades of CDD paralleled decreasing JOA scores in the population studied.

Comprehensive analysis of pedicle screw implantation in the C7 vertebra using computed tomography-based three-dimensional models.

BACKGROUND: From a biomechanical point of view, pedicle screws (PS) are better than other kinds of screws for implantation in the seventh cervical vertebra (C7). However, the application of PS is limited because of the high risk of severe complications. It is essential to define the optimal entry point and trajectory. The aim of this study was to comprehensively analyze the starting point and trajectory for C7 PS insertion using three dimensional (3D) models. METHODS: Overall, 60 subjects aged 18 to 67 years old were included. All CT images were used to construct 3D computer models of the C7 vertebrae. A new coordinate system was established for the next evaluation. The pedicle axis was calculated with respect to the entire pedicle; then, the ideal entry point, screw diameter and length, sagittal angle and lateral angle were assessed. RESULTS: All the ideal entry points were located at the medial superior to lateral notch (LN), and the mean distance between the entry point and LN was 5.86 ± 1.67 mm in the horizontal direction and 3.47 ± 1.57 mm in the vertical direction. The mean distance between the entry point and the middle point of the inferior edge of the C6 articular process (MP) was 0.74 ± 1.83 mm in the horizontal direction. The mean sagittal angle of the pedicle axis was 90.42°, and the mean pedicle transverse angle was 30.70°. The average diameter and length of the PS were 6.51 ± 0.76 mm and 31.58 ± 4.40 mm, respectively. CONCLUSIONS: This study provided a novel method to calculate the ideal starting point and trajectory for C7 PS insertion. These measurements may be helpful for preoperative planning. It is recommended that 3D CT imaging is used preoperatively to carefully evaluate the anatomy of each individual.

Spinal cord injury in an adult patient with thoracic butterfly vertebra: a case report and review of the literature.

BACKGROUND: Butterfly vertebrae are a rare congenital vertebral anomaly. An overlap of this spinal anomaly with other diseases has been reported. However, to the authors' knowledge, the coexistence of butterfly vertebrae and spinal cord injury has not been reported in the literature. CASE PRESENTATION: A 42-year-old male was admitted to our emergency department after a motor vehicle accident. His complaint was back pain, and he was unable to move both lower limbs. Upon physical examination, the patient was not ambulatory. Sensory examination revealed the absence of sensation below the T12 level. The strength of the bilateral lower limbs was grade 0. The patient received a radiographic evaluation. The initial diagnosis was T11 fracture with complete paraplegia of the lower limbs. Magnetic resonance imaging (MRI) was then performed. Sagittal MRI demonstrated an isointense lesion on T1-weighted imaging and a high-signal spindle-like lesion on T2-weighted imaging of the spinal cord adjacent to the T11 vertebra. The fat-suppressed sequence also revealed hyperintensities of the cord. There was no evidence of acute injury of the T11 vertebral body except for cuneiform anterior wedging. The patient was ultimately diagnosed with complete paraplegia with a T11 butterfly vertebra. He underwent urgent posterior decompressive and fixation surgery from T10 to T12. His postoperative recovery was uneventful. CONCLUSIONS: The coexistence of a butterfly vertebra with spinal cord injury was reported for the first time. Although butterfly vertebrae may be incidentally detected, it is important to be familiar with their radiographic features to distinguish them from fractures.

Risk Factors for Lower Limb Deep Vein Thrombosis in Patients With Single-Level Lumbar Fusion: A Prospective Study of 710 Cases.

Lower limb deep vein thrombosis (DVT) is not an uncommon postoperative complication of spinal fusion surgery. However, the related risk factors identified in previous studies remain controversial. This study aimed to investigate risk factors for lower limb DVT in patients with single-level lumbar fusion surgery. Between January 2010 and December 2016, a total of 710 patients undergoing lumbar fusion were recruited for this study, including 172 males and 538 females (aged 18-75 years). Deep vein thrombosis was detected by ultrasonography. Accordingly, patients were divided into the DVT group and the non-DVT group and compared in terms of operative data, underlying diseases, and biochemical data. Additionally, logistic regression analysis was performed to identify risk factors for lower limb DVT. The incidence of lower limb DVT was 11.8% (84 of 710 cases). Five patients were symptomatic, with lower limb pain and swelling. Two patients developed pulmonary embolism and 1 died. Binary logistic regression indicated that advanced age (P = .001, odds ratio [OR] = 2.86, 95% CI: 1.85-5.12), hypertension (P = .006, OR = 4.10, 95% CI: 1.09-2.30), and increased d-dimer (P < .001, OR = 3.49, 95% CI: 2.05-6.36) were risk factors for postoperative DVT. In conclusion, for patients with single-level lumbar fusion, advanced age, increased d-dimer, and hypertension may contribute to DVT development after spinal fusion surgery. Therefore, patients with these risk factors should be protected during the perioperative period.

Anterior cervical discectomy and fusion versus hybrid surgery in multilevel cervical spondylotic myelopathy: A meta-analysis.

OBJECTIVE: A meta-analysis was performed to compare the radiographic and surgical outcomes between anterior cervical discectomy and fusion (ACDF) and hybrid surgery (HS, corpectomy combined with discectomy) in the treatment for multilevel cervical spondylotic myelopathy (mCSM). SUMMARY OF BACKGROUND DATA: Both ACDF and HS are used to treat mCSM, however, which one is better treatment for mCSM remains considerable controversy. METHODS: An extensive search of literature was searched in PubMed/Medline, Embase, the Cochrane library, CNKI, and WANFANG databases on ACDF versus HS treating mCSM from January 2011 to December 2017. The following variables were extracted: blood loss, operation time, fusion rate, Cobb angles of C2-C7, total complications, dysphagia, hoarseness, C5 palsy, infection, cerebral fluid leakage, epidural hematoma, and graft subsidence. Data analysis was conducted with RevMan 5.3 and STATA 12.0. RESULTS: A total of 4 studies including 669 patients were included in our study. The pooled analysis showed that there were no significant difference in the operation time, fusion rate, Cobb angles of C2-C7, dysphagia, hoarseness, C5 palsy, infection, cerebral fluid leakage, epidural hematoma, and graft subsidence. However, there were significant difference between 2 groups in blood loss [P < .00001, SMD = -30.29 (-45.06, -15.52); heterogeneity: P = .38, I = 0%= and total complications [P = .04, OR = 0.66 95%CI (0.44, 0.98); heterogeneity: P = .37, I = 4%]. CONCLUSIONS: Based on our meta-analysis, except for blood loss and total complications, both ACDF and hybrid surgery are effective options for the treatment of multilevel cervical spondylotic myelopathy.

3D-Printed Poly(ε-caprolactone) Scaffold Augmented With Mesenchymal Stem Cells for Total Meniscal Substitution: A 12- and 24-Week Animal Study in a Rabbit Model.

BACKGROUND: Total meniscectomy leads to knee osteoarthritis in the long term. The poly(ε-caprolactone) (PCL) scaffold is a promising material for meniscal tissue regeneration, but cell-free scaffolds result in relatively poor tissue regeneration and lead to joint degeneration. HYPOTHESIS: A novel, 3-dimensional (3D)-printed PCL scaffold augmented with mesenchymal stem cells (MSCs) would offer benefits in meniscal regeneration and cartilage protection. STUDY DESIGN: Controlled laboratory study. METHODS: PCL meniscal scaffolds were 3D printed and seeded with bone marrow-derived MSCs. Seventy-two New Zealand White rabbits were included and were divided into 4 groups: cell-seeded scaffold, cell-free scaffold, sham operation, and total meniscectomy alone. The regeneration of the implanted tissue and the degeneration of articular cartilage were assessed by gross and microscopic (histological and scanning electron microscope) analysis at 12 and 24 weeks postoperatively. The mechanical properties of implants were also evaluated (tensile and compressive testing). RESULTS: Compared with the cell-free group, the cell-seeded scaffold showed notably better gross appearance, with a shiny white color and a smooth surface. Fibrochondrocytes with extracellular collagen type I, II, and III and proteoglycans were found in both seeded and cell-free scaffold implants at 12 and 24 weeks, while the results were significantly better for the cell-seeded group at week 24. Furthermore, the cell-seeded group presented notably lower cartilage degeneration in both femur and tibia compared with the cell-free or meniscectomy group. Both the tensile and compressive properties of the implants in the cell-seeded group were significantly increased compared with those of the cell-free group. CONCLUSION: Seeding MSCs in the PCL scaffold increased its fibrocartilaginous tissue regeneration and mechanical strength, providing a functional replacement to protect articular cartilage from damage after total meniscectomy. CLINICAL RELEVANCE: The study suggests the potential of the novel 3D PCL scaffold augmented with MSCs as an alternative meniscal substitution, although this approach requires further improvement before being used in clinical practice.

Chondrogenic Potential of Peripheral Blood Derived Mesenchymal Stem Cells Seeded on Demineralized Cancellous Bone Scaffolds.

As a cell source with large quantity and easy access, peripheral blood mesenchymal stem cells (PBMSCs) were isolated and seeded in porcine demineralized cancellous bone (DCB) scaffolds, cultured in chondrogenic medium and evaluated for in vitro chondrogenesis. Bone marrow MSCs (BMMSCs) and articular cartilage chondrocytes (ACCs) underwent the same process as controls. The morphology, viability and proliferation of PBMSCs in DCB scaffolds were similar to those of BMMSCs and ACCs. PBMSCs and BMMSCs showed similar chondrogenesis potential with consistent production of COL 2 and SOX 9 protein and increased COL 2 and AGC mRNA expressions at week 3 but the COL 2 protein production was still less than that of ACCs. Minimal increase of hypertrophic markers was found in all groups. Relatively higher ALP and lower COL 10 mRNA expressions were found in both MSCs groups at week 3 than that in ACCs, whereas no significant difference of COL 1 and SOX 9 mRNA and MMP 13 protein was found among all groups. To conclude, PBMSCs shared similar proliferation and chondrogenic potential with BMMSCs in DCB scaffolds and could be an alternative to BMMSCs for cartilage tissue engineering. Further optimization of chondrogenesis system is needed regardless of the promising results.

17ß-Estradiol Protects Rat Annulus Fibrosus Cells Against Apoptosis via α1 Integrin-Mediated Adhesion to Type I Collagen: An In-vitro Study.

BACKGROUND 17ß-Estradiol (E2) has been reported to protect annulus fibrosus (AF) cells in vitro against interleukin-1ß (IL-1ß)-induced apoptosis in a concentration-dependent manner. However, its time-response effect remains unexplored. In addition, integrin α2/collagen II interaction has been reported to influence the apoptosis of nucleus pulposus cells in vitro. Thus, we hypothesized that integrin α1/collagen II might play a role in exerting the anti-apoptosis effect by E2. The aim of the current study was to further investigate the anti-apoptotic effect of E2 and determine the role of integrin a1/collagen II interaction. MATERIAL AND METHODS Rat AF cells were primary cultured and used for the following experiments. AF cells were identified by immunocytochemistry of type I collagen. Cell apoptosis was detected by fluorescence-activated cell sorter (FACS) analysis. The activity of active caspase-3 was determined by use of a caspase-3 detection kit. AF cell adhesion to type I collagen was determined by cell adhesion assay. Protein level of integrin subunit α1 was quantified by Western blot and mRNA expression was determined by real-time qPCR. RESULTS The immunocytochemistry of type I collagen revealed that cell purity was eligible for the following experiments with 98% of purity. FACS analysis indicated time-dependent anti-apoptosis effect of E2 at time points of 6 h, 12 h, and 24 h, which was confirmed by Caspase-3 activity. Furthermore, cell adhesion assay showed that E2 significantly increased cell binding to 95% of control, and qPCR and Western blot analysis showed that E2 effectively upregulated integrin α1. However, estrogen receptor antagonist ICI182780 prohibited the effect of E2. CONCLUSIONS This study shows that E2 protects against apoptosis in a time-dependent manner, and α1 integrin-mediated adhesion to collagen II is essential for estrogen-dependent anti-apoptosis in rat annulus fibrosus cells in vitro.

Novel customized template designing for patellar resurfacing in total knee arthroplasty.

Due to the irregular shape of patella and difficulty in identifying its bony landmarks, it can be a challenge for surgeons to accurately and symmetrically perform patellar resurfacing. Three-dimensional (3D) models of 20 patellae were generated from computed tomographic images. Using a computer-assisted preoperative planning technique, customized template designs were developed to guide patellar resurfacing. The patellar models and corresponding templates were produced through rapid prototyping. The accuracy of this technique was assessed after applying the templates on patellar models and cadaver specimens, respectively. Using preoperative planning and predesigned templates, a significant improvement in symmetric patellar resurfacing, with a mean angle of 1.21° mediolateral (ML) obliquity and 1.95° superoinferior (SI) obliquity, was observed compared with the conventional sawguide technique (mean angle of ML and SI was 4.13°, 4.95°, respectively). Additionally, the use of customized templates reproduced the desired preplanned patellar resection. Preoperative planning with 3D imaging and customized templates improved the accuracy of patellar resurfacing in terms of the obliquity and thickness. CLINICAL RELEVANCE: A novel customized template designed for patellar resectioning will benefit surgeons in performing patellar resurfacing. This technique will provide accurate patellar resurfacing in clinical practice. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1798-1803, 2016.

A systematic review of double-bundle versus single-bundle posterior cruciate ligament reconstruction.

BACKGROUND: Posterior Cruciate Ligament (PCL) ruptures are common sports injuries. One of the key controversies in PCL reconstruction is whether double-bundle reconstruction provides biomechanical and clinical outcomes superior to single-bundle reconstruction. METHODS: We performed a comprehensive search in multiple databases to evaluate the advantages of single-bundle or double bundle reconstructions in anteroposterior stability, graft tension, rotational stability, and functional outcome. RESULTS: Biomechanical comparisons evaluating anteroposterior stability described either no difference or increased stability in double-bundle reconstructions. Comparing these results is complicated by different graft choices, tensioning techniques, and tunnel positions. Biomechanical studies of graft tension demonstrated conflicting results regarding the optimal reconstruction technique. Seven retrospective clinical studies of single- and double-bundle reconstructions with methodological limitations reported no difference in clinical outcome. CONCLUSIONS: The superiority of single-bundle or double-bundle posterior cruciate ligament reconstruction remains uncertain.

Optimal patellar alignment with minimally invasive approaches in total knee arthroplasty after a minimum five year follow-up.

PURPOSE: Patellofemoral syndrome is still a common complication after total knee arthroplasty (TKA). However, the effects of specific surgical approaches on patellar tracking and alignment remain incompletely understood. In this study, we compared patellar alignment in patients who underwent TKA via three different techniques. METHODS: A total of 96 patients who completed a minimum follow-up of five years were involved in three groups: 30 patients were treated with the traditional medial parapatellar approach (MPP group), 35 patients were treated with the mini-medial parapatellar approach (MMP group) and 31 were treated with a quadriceps-sparing approach (QS group). Radiographic data for patellar alignment and clinical results were compared. RESULTS: Patellar tilt and patellar displacement at the final follow-up evaluation differed significantly among the three groups [P < 0.01, analysis of variance (ANOVA)]. The MMP and QS groups exhibited more proper patellar alignment than the MPP group. The clinical results did not differ significantly among the groups (P > 0.05, ANOVA). In addition, there were no correlations between postoperative patellar alignment and clinical scores. CONCLUSIONS: The results of this study indicate that TKA performed using minimally invasive approaches yields superior patellar alignment compared to the traditional MPP approach.

Intraoperative anthropomorphic study of anterior femoral condyles compared with sizing of femoral arthroplasty.

PURPOSE: The present study was designed to compare the dimensions of the anterior femoral condyle with those of the anterior component flange using intraoperative morphological data. METHODS: Overall, 1227 knees in 962 patients were included in this study. The height of the anterior lateral/medial condylar height (ALCH/AMCH) was measured and compared between men and women. These morphological data were compared with the dimensions of the chosen component for each patient. The lateral/medial anterior femoral offset was calculated, and the over-/understuffing rates were compared between men and women. RESULTS: The median ALCH in men was 8.5 mm (6.5, 10.0 mm) versus 7.0 mm (6.0, 9.0 mm) in women. The median AMCH in men was 4.0 mm (2.5, 6.0 mm) versus 3.5 mm (2.5, 6.0 mm) in women. There was a significant difference between the genders with respect to ALCH (p < 0.05). When the dimensions of the component were compared with those of the native knee, the anterior lateral flange height was smaller than the native knees (1.3 mm in male, 0.7 mm in female), but the anterior medial flange height was larger than the corresponding condyle (1.8 mm in male, 1.8 mm in female). A significant difference was observed between the genders with respect to the ideal fit rate of ALCH (p < 0.01). CONCLUSION: The results demonstrate that gender differences exist in the anterior lateral condyles of knees. The anterior flange of component is not designed to precisely reproduce normal trochlear anatomy. LEVEL OF EVIDENCE: II.

Are There Any Clinical and Radiographic Differences Between Quadriceps-sparing and Mini-medial Parapatellar Approaches in Total Knee Arthroplasty After a Minimum 5 Years of Follow-up?

BACKGROUND: Although the early clinical outcomes of total knee arthroplasty (TKA) using minimally invasive surgery techniques have been widely described, data on the mid- to long-term outcomes are limited. We designed a retrospective study to compare the two most common TKA techniques - The modified quadriceps-sparing (m-QS) approach and the mini-medial parapatellar (MMP) approach - In terms of the clinical and radiographic parameters, over a minimum follow-up period of 5 years. METHODS: The m-QS approach was used in 31 knees and the MMP approach, in 36 knees. Knees in both groups were compared for component position and alignment, knee alignment, length of the skin incision, range of motion, Visual Analog Scale score, muscle torques, Knee Society Score, Western Ontario and McMaster Universities Osteoarthritis Index, and number of complications. RESULTS: There were no major intergroup differences in any of the clinical and radiographic outcomes assessed at the final follow-up examination. CONCLUSIONS: On the basis of numbers studied, the m-QS group, which requires more technique, showed equivalent results with the MMP group in the postoperative 5 years. Preservation of the extensor mechanism in the m-QS approach could not ensure any improvement in the clinical outcomes during the mid-term follow-up duration.

Coexistence of multiple rare spinal abnormalities in type 1 neurofibromatosis: a case report and literature review.

Orthopaedic involvement is the most common clinical presentation of Neurofibromatosis type 1 (NF-1) patients with the spinal abnormalities more frequently affected. In the spinal deformities of NF-1 patients, despite the scoliosis is the most frequent finding, several distinctive radiographic features, such as dural ectasia, defective pedicles, and spondylolisthesis, are relatively less common. Here, we reported a 16-year-old boy diagnosed with NF-1 who presented with dural ectasia, defective pedicles, and spondylolisthesis concomitantly, described the surgical treatment and provided a literature review. The boy complained of low back and leg pain for two months. On clinical examination, the patient showed multiple café au lait spots on his back and no neurological deficit. He had a family history of neurofibromatosis as his father suffering from NF-1. Imaging results demonstrated mild scoliosis, posterior scalloping of the lumber spine, L5 spondylolisthesis on plain radiographs, and marked dural ectasia of L3-L5 on MRI. Furthermore, the CT scan showed presence of thin pedicles at L3, bilateral symmetrical pedicle clefts at L4, and pars interarticularis fractures at L5. The patient received a long level posterior fusion from L1 to S1 with pedicle screws. Iliac crest autogenous graft mixed with artificial bone were used to achieve solid arthrodesis. At nine-month follow-up, the patient was asymptomatic and able to live a normal life. Our observation demonstrated that familiarity with those distinctive features in NF-1 patients could be contributed to making an early diagnosis and optimizing treatment.

Does curve convexity affect the surgical outcomes of thoracic adolescent idiopathic scoliosis?

BACKGROUND: Major left thoracic (LT) curve is an atypical type in adolescent idiopathic scoliosis (AIS) and showed independent clinical characteristics and natural history compared to major right thoracic (RT) curve. However, it's unclear whether the convexity of major thoracic curve would affect the surgical outcomes and risk of complications. A retrospective follow-up study was conducted to investigate whether the convexity of major thoracic curve would affect the surgical outcomes of patients with main thoracic AIS. METHODS: Twelve LT-AIS patients underwent corrective spinal instrumentation and fusion were retrieved, and twelve patients with main RT-AIS matched for gender, chronological age, curve type, magnitude and surgical strategy were selected as control. All patients underwent at least 2-year follow-up. The pre- and post-operative radiographic parameters, intraoperative data and functional outcome assessed by Scoliosis Research Society questionnaire 22 (SRS-22) were analyzed and compared between two groups. RESULTS: Patients with LT- and RT-AIS presented with similar magnitudes of thoracic curves, flexibility, fusion level and correction rate. Compared with RT-AIS, patients with LT-AIS showed longer operation time (average, 364 vs. 348 min) and larger amount intraoperative estimated blood loss (2,060 vs. 1,720 ml) although the differences were not statistically significant (p > 0.05). With at least 2-year follow-up, patients in two groups showed comparable loss of correction, coronal and sagittal balance, and the sagittal profiles. With regard to functional outcome, the scores of five categories of SRS-22 questionnaire were similar between two groups. No neurological or vascular complication was observed in these patients. CONCLUSIONS: The radiographic and functional outcomes of LT-AIS patients underwent operation were comparable to those with RT-AIS. Longer operation time and more intraoperative blood loss may be expected in instrumentation and fusion for patients with LT-AIS, which might be because of the inconvenience on the surgical procedure.

[Pulmonary dysfunction patterns in patients with Marfan and Marfanoid syndrome associated with scoliosis and the influencing factors].

OBJECTIVE: To investigate the impairment pattern and the influencing factors of pulmonary function in patients with Marfan and Marfanoid syndrome associated scoliosis (MS). METHODS: In this retrospective study, totally 25 MS patients (aged 11 - 20 years, 11 boys and 14 girls) who received posterior instrumentation and fusion (Group A) and 38 adolescent idiopathic scoliosis (AIS) patients (Group B) (aged 10 - 19 years, 11 boys and 27 girls) were included from February 1998 to September 2007. The curve pattern was matched in both groups. The preoperative pulmonary function test (PFTs) were compared in two groups. And the parameters influencing the preoperative pulmonary function were analyzed in group A. RESULTS: In Group A, the Cobb angle of thoracic curve was negatively correlated with the percentage of predicted pulmonary volumes (VC%, FVC% and FEV1%) (r = -0.514, -0.503, -0.464, P < 0.05). And the reduction of lung function parameters (VC%, FVC%, FEV1% and MMEF%) was more severe in Group A than in Group B with compared magnitude of thoracic curve (P < 0.05). In Group A, the extent of impairment of pulmonary function in patients with the number of vertebrae involved ≥ 8 were more severe than those involved < 8 vertebrae (P < 0.05). However, there was no significant difference of deterioration of lung function between the higher apex (T4₋8) subgroup and lower apex (T9₋12) subgroup. And no correlation was found between thoracic kyphosis and the degrees of impairment of respiration function. CONCLUSIONS: Patients with MS have mixed ventilation dysfunction, which is more severe than AIS patients with matched age and Cobb angle. The pulmonary dysfunction in MS patients can be influenced by the severity of thoracic curve and the number of involved vertebrae.

[The pulmonary dysfunction patterns in scoliosis associated with neurofibromatosis type I].

OBJECTIVE: To investigate the pulmonary dysfunction patterns in patients of scoliosis associated with neurofibromatosis type I (NF1) and to identify factors affecting the pulmonary function in patients with scoliosis associated with NF1. METHODS: Preoperative pulmonary function tests (PFTs) were evaluated in 100 patients with scoliosis [NF1 group, 36 cases; idiopathic scoliosis (IS) group, 64 cases] from January 2003 to June 2009. According to location of apical vertebra and dystrophic change in patients with NF1, the parameters of pulmonary function [vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), maximal mid-expiratory flow (MMEF), maximal voluntary ventilation (MVV)] were compared between NF1 group and IS group, and between the subgroups of NF1. The correlation between pulmonary function parameters and radiographic parameters of scoliosis was analyzed. RESULTS: The VC, FVC, FEV1, MMEF, MVV in NF1 group and IS group were of no significant difference (P > 0.05). In NF1 patients, the pulmonary dysfunction was more severe in thoracic subgroup than non-thoracic subgroup (P < 0.05), while there was no difference between dystrophic scoliosis and non-dystrophic scoliosis (P > 0.05). The location of apical vertebra and the severity of scoliosis correlated significantly with the pulmonary dysfunction in NF1 group. CONCLUSIONS: The pattern of pulmonary dysfunction in scoliosis associated with NF1 is similar with IS. Pulmonary dysfunction is more severe in thoracic scoliosis. The location of apical vertebra and the severity of scoliosis are the risk factors influencing the pulmonary dysfunction.