OBJECTIVETo analyze the causes of the complications associated with the pedicle screw fixation during and after operation, as well as the methods for prevention and treatment.

METHODSFrom January 1988 to December 1999, 475 patients who underwent pedicle screw fixation for various spinal disorders were reviewed retrospectively with statistical analysis.

RESULTSFour hundred and twenty-eight patients (90.1% of all) were followed up for (6.0 +/- 3.7) years. Complications of CD, DRFS, Dick, RF and steffee among 72 cases (80% of all) occurred during the operation of pedical screw fixation in 26 cases with the incidence of 5.5% and after the operation in 64 cases with the incidence of 15%. The incidence of operative/postoperative complications were 0-12.9% in CD, 6.8%-11.9% in DRFS, 7.3%-12.7% in Dick, 2.4%-19.5% in RF, and 10.1%-21.5% in Steffee respectively. The main complications included pseudoarthrosis, pedicle screw broken, pedicle screw malposition and so on. The complications were mainly due to unskilled technique of pedicle screw fixation, implant defect in design and so on.

CONCLUSIONSThe complications associated with the technique of pedicle screw fixation must not be neglected. The main causes are laid on unskilled technique of pedicle screw fixation and implant defect in design.

Equipment Failure ; statistics & numerical data ; Female ; Follow-Up Studies ; Humans ; Incidence ; Internal Fixators ; Male ; Postoperative Complications ; epidemiology ; etiology ; Pseudarthrosis ; epidemiology ; etiology ; Retrospective Studies ; Spinal Diseases ; surgery ; Spinal Fusion ; methods

OBJECTIVETo investigate the mid-term radiological outcome of sagittal alignment of overall cervical spine and the functional spinal unit after replacement surgery with Bryan cervical disc prosthesis.

METHODSEighteen patients with cervical disc disorder were performed cervical disc replacement with 20 Bryan discs from November 2005 to May 2010, including single-level 16 cases and bi-level 2 cases. The patient consisted of 13 males and 5 females with age ranging from 38 to 59 years (average, (47 ± 6) years). Fourteen cases with overall cervical lordotic alignment and segmental lordotic alignment per-operatively (group 1) and 4 others with segmental kyphotic alignment and overall cervical kyphotic alignment per-operatively (group 2). The overall sagittal alignment (C(2-7)) and segmental sagittal alignment were measured pre-operatively, post-operatively and at final follow-up to evaluate the outcome.

RESULTSAll cases obtained the follow-up with an average of (24 ± 5) months (range 12 to 53 months). To the mean overall cervical alignment, there were 9.9° ± 1.9° per-operatively, 12.8° ± 2.1° post-operatively and 11.6° ± 1.8° at final follow-up in group 1 and -1.8° ± 0.8° per-operatively, 7.3° ± 1.3° post-operatively and 5.0° ± 2.1° at final follow-up in group 2. There were statistical significance between per-operatively and post-operatively (t = -2.987 and -5.058, P < 0.05) and no statistical significance between post-operatively and final follow-up (P > 0.05) in both groups. To the mean segmental alignment there were 2.6° ± 0.8° per-operatively, 5.4° ± 1.0° post-operatively and 4.3° ± 0.9° at final follow-up in group 1 and -3.0° ± 0.8° per-operatively, 3.8° ± 1.3° post-operatively and 0.3° ± 2.8° at final follow-up in group 2. There were statistical significance between per-operatively and post-operatively in both groups (t = -3.829 and -4.086, P < 0.05) and between post-operatively and final follow-up in group 1 (t = 2.630, P < 0.05)but not in group 2 (P > 0.05).

CONCLUSIONSThe Bryan cervical disc prosthesis has a good mid-term outcome for maintaining sagittal alignment of overall cervical spine and the functional spinal unit. Long-term follow-up should be needed to assess the long-term functionality of the prosthesis.

Adult ; Cervical Vertebrae ; surgery ; Female ; Follow-Up Studies ; Humans ; Intervertebral Disc ; surgery ; Joint Prosthesis ; Male ; Middle Aged ; Retrospective Studies ; Spinal Fusion ; Spinal Osteophytosis ; surgery ; Treatment Outcome

OBJECTIVETo compare and evaluate instrumented posterior fusion with instrumented circumferential lumbar fusion in the treatment of lumbar stenosis with low degree lumbar spondylolisthesis.

METHODSFrom April 1998 to April 2003, 45 patients who suffered from lumbar stenosis with low degree lumbar spondylolisthesis were divided into 2 groups (A and B) at random. The patients in group A (n = 24, average age 54 years old) were performed decompressive laminectomy, intertransverse process arthrodesis with bone grafting and transpedicle instrumentation of solid connection (SOCON) system. The patients in group B (n = 21, average age 53 years old) were performed the same procedure as group A except adding posterior lumbar interbody fusion (PROSPACE). The main levels of lumbar spondylolisthesis in 2 groups was L(4 - 5) or L(5)-S(1). All cases were classified as degree 1 to degree 2. All patients in the two groups received preoperative myelography or CTM, and were diagnosed lateral recess stenosis and(or) central lumbar canal stenosis.

RESULTSAll the patients were followed up from 12 to 72 months. In group A, the results showed that the preoperative clinical symptoms disappeared completely in 12 of 24 patients, pain relief was seen in 91.7% (22/24), anatomical reduction rate was 91.7%. No infection or neurologic complication occurred in this series. In group B, the results showed that the preoperative clinical symptoms disappeared completely in 13 of 21 patients, pain relief was seen in 90.5% (19/21), anatomical reduction rate was 95.2%. Four cases of infection or neurologic complication occurred in this series. Two groups had no significant difference in follow-up clinical outcome and anatomical reduction rate. But group A had better intraoperative circumstances and postoperative outcome than group B, group B had better postoperative parameters in X-ray of angle of slipping and disc index than group A.

CONCLUSIONSThe best surgical treatment method of lumbar stenosis with low degree lumbar spondylolisthesis is complete intraoperative decompressive laminectomy, reduction with excellent transpedicle system instrumentation and solid fusion after bone grafting. The use of cage should be conformed to strict indications.

Adolescent ; Adult ; Aged ; Female ; Humans ; Laminectomy ; Lumbar Vertebrae ; surgery ; Male ; Middle Aged ; Retrospective Studies ; Spinal Fusion ; methods ; Spinal Stenosis ; complications ; surgery ; Spondylolysis ; complications ; surgery ; Treatment Outcome

Adolescent ; Female ; Hereditary Sensory and Autonomic Neuropathies ; surgery ; Humans ; Hypohidrosis ; surgery ; Pain ; Spine ; surgery

BACKGROUNDPulmonary problems often occur in patients with early-onset scoliosis (EOS). However, lung function in patients with EOS after growing rod surgery has not been documented. The aim of this study was to investigate lung function after the treatment for EOS with growing rod and its possible correlative factors.

METHODSEight patients with EOS were treated with growing rod surgery at Peking Union Medical College Hospital from September 2002 to September 2009. Four patients had finished the final fusion surgery (group 1), and the other 4 (group 2) were in the process of periodic lengthening. Preoperative forced vital capacity (FVC), ratio of FVC to predicted FVC, forced expiratory volume in 1 second (FEV1), ratio of FEV1 to predicted FEV1, and radiographic measurements of Cobb's angle and C7-S1 distance were recorded. Lung function changes and correlations between lung function changes and radiographic changes (Cobb's angle and C7-S1 distance) were analyzed.

RESULTSIn group 1, FVC and FEV1 both increased. FVC showed a significant difference (P = 0.01), but FEV1 did not (P = 0.05). In group 2, FVC and FEV1 also increased, and both showed a significant difference (P = 0.04 and P = 0.02, respectively). Ratio of FVC to predicted FVC and ratio of FEV1 to predicted FEV1 changed similarly and did not show statistical differences in the 2 groups. There were no significant correlations between lung function changes and radiographic changes (Cobb's angle and C7-S1 distance) (P = 0.10 and P = 0.41, respectively).

CONCLUSIONSLung function increases after growing rod surgery in patients with EOS. Lung function changes do not correlate with Cobb's angle changes or C7-S1 distance changes.

Child ; Female ; Forced Expiratory Volume ; physiology ; Humans ; Male ; Orthopedic Procedures ; adverse effects ; Scoliosis ; physiopathology ; surgery ; Vital Capacity ; physiology

OBJECTIVETo evaluate the biomechanical stability of Shen's instrumentation in the management of thoracolumbar fractures.

METHODSThe ranges of movement (ROM) in three dimensions of twelve T(12) - S(3) specimen of fresh adult cadavers were measured sequentially in the states of normal, injured, GSS and SOCON fixation, fatigued GSS and SOCON fixation. Data were then compared.

RESULTSFor the L(2 - 3) segment, the average normal ROM in flexion was 8.3 degrees. In the established spondylolisthesis models, the ROM was 14.7 degrees. After fixation with SOCON, the ROM was decreased to 3.0 degrees, indicating that SOCON fixation can produce good stability. The ROM after fatigue test was 3.6 degrees, significantly lower than that of the normal state, indicating that SOCON still produces good stability after fatigue. For the L(4 - 5) segment, the average normal ROM in flexion was 8.6 degrees. In the established spondylolisthesis models, the ROM was 13.7 degrees. After GSS fixation, the ROM was decreased to 3.2 degrees, significantly lower than that in the normal state, indicating that GSS fixation can produce good stability. ROM after fatigue test was 3.7 degrees, significantly lower than that of the normal state, indicating that GSS can produce good stability after fatigue. The ROM measurements in the other five directions were similar to those for flexion described above.

CONCLUSIONGSS produces good stability for spondylolisthesis, good fatigue resistance, and can be used in pedicle screw revision surgery. There were no significant differences between GSS and SOCON.

Adult ; Biomechanical Phenomena ; Cadaver ; Humans ; Internal Fixators ; Joint Dislocations ; surgery ; Lumbar Vertebrae ; injuries ; Male ; Range of Motion, Articular ; Spinal Fusion ; instrumentation ; methods ; Spinal Injuries ; physiopathology ; surgery ; Thoracic Vertebrae ; injuries ; Young Adult

OBJECTIVETo observe the characteristics of gene expression of type X collagen in the cartilage of end-plate and the fibrous annulus in the intervertebral disc of idiopathic scoliosis (IS) patients.

METHODInvestigating the expression of type X collagen in the peak disc and the lower end disc of 21 IS patients, the peak disc of 16 congenital scoliosis (CS) and the lumbar disc of 3 normal people (according with the principle of medical ethnics) by reverse transcript polymerase chain reaction.

RESULTSThe expression of type X collagen in the concave side of IS peak disc was higher than the convex side (P < 0.05). There was no significant difference of gene expression of type X collagen between the convex side and the concave side of the lower end disc (P > 0.05). The gene expression of type X collagen in the IS peak disc was higher than those of lower end disc (P < 0.05). For the CS peak discs, the expression of type X collagen of the concave side was higher than the convex side (P < 0.05).

CONCLUSIONThe expression of type X collagen of the IS peak disc increases, and the expression of type X collagen of the concave side is higher than the convex side. These changes may be secondary.

Adolescent ; Child ; Collagen Type X ; genetics ; metabolism ; Female ; Gene Expression ; Humans ; Intervertebral Disc ; metabolism ; Male ; Scoliosis ; genetics ; metabolism

OBJECTIVETo observe early clinical efficacy of general spine system (GSS) in spondylolisthesis combined with lumbar canal stenosis, lumbar decompression, reduction and bone graft.

METHODSSixteen patients with degenerative lumbar spondylolisthesis combined with lumbar canal stenosis, 10 male, 6 female, average age 58.5 years (range 42 - 72 years) underwent lumbar decompression, bone graft and internal fixation using GSS. Preoperatively 10 patients had degree I spondylolisthesis and 6 patients had degree II spondylolisthesis. Clinical efficacy, reduction effectiveness and complications were recorded.

RESULTSThe 16 patients in this group were followed up postoperatively for an average of 21.2 months (18 - 24 months). At latest follow-up after surgery, preoperative clinical symptoms had disappeared completely in 15 of 16 patients, and low back pain relief was seen in 15 patients. Average duration of surgery was 170 min (120 - 270 min), and average blood loss was 375 ml (100 - 800 ml). X-ray results showed complete reduction for all spondylolisthesis patients, and results remained good in follow-up. Dura mater tearing, pedical fracture, nerve injury and other surgical complication did not occur. Screw breakage, screw loosening and instrument loosening at the screw-rod juncture were not observed after surgery or in follow-up.

CONCLUSIONGSS provides good reduction for spondylolisthesis, and shows good early clinical efficacy.

Adult ; Aged ; Bone Transplantation ; Decompression, Surgical ; Female ; Follow-Up Studies ; Humans ; Internal Fixators ; Lumbar Vertebrae ; surgery ; Male ; Middle Aged ; Spinal Fusion ; instrumentation ; methods ; Spinal Stenosis ; etiology ; Spondylolisthesis ; surgery ; Treatment Outcome

OBJECTIVETo evaluate the outcome of two methods for stabilization and fusion: posterolateral fusion and circumferential fusion involving posterior lumbar interbody fusion for lumbar stenosis with Grades 1 and 2 lumbar spondylolisthesis.

METHODSFrom April 1998 to April 2003, 45 patients suffering from lumbar stenosis with low degree lumbar spondylolisthesis treated in our hospital were retrospectively reviewed and assigned to two groups. Among them, 24 patients (group A) were treated with instrumented posterolateral fusion and 21 patients (group B) with instrumented circumferential fusion. The two groups were compared for clinical and radiological outcomes.

RESULTSAll patients were followed up for 12 to 72 months. In group A, results showed preoperative clinical symptoms disappeared completely in 12 of 24 patients, and pain relief was seen in 91.7% (22/24). Two cases suffered from residual symptoms. Twenty-two cases obtained complete reduction of olisthy vertebral bodies, and anatomical reduction rate was 91.7%. No infection or neurological complication occurred in this group. In group B, results showed preoperative clinical symptoms disappeared completely in 13 of 21 patients, and pain relief was seen in 90.5% (19/21). One case suffered from residual symptoms. Twenty cases obtained complete reduction of the olisthy vertebral bodies, and anatomical reduction rate was 95.2%. Four cases of infection or neurological complication occurred in this group. Both groups indicated no significant difference in clinical outcomes and anatomical reduction rate during follow-up. But group A had better intraoperative circumstances and postoperative outcome than group B, while group B had better postoperative parameters in X-ray of Angle of Slipping and Disc Index than group A.

CONCLUSIONSThe first choice of surgical method for lumbar stenosis with low degree lumbar spondylolisthesis is instrumented posterolateral fusion. Only when patients suffer from severe preoperative disc degeneration and low back pain or intervertebral instability should we consider indications for additional use of CAGE.

Adult ; Aged ; Female ; Follow-Up Studies ; Humans ; Lumbar Vertebrae ; surgery ; Male ; Middle Aged ; Radiography ; Retrospective Studies ; Spinal Fusion ; methods ; Spinal Stenosis ; diagnostic imaging ; pathology ; surgery ; Spondylolisthesis ; diagnostic imaging ; pathology ; surgery ; Treatment Outcome

OBJECTIVETo compare the effect of posterior correction and fusion between segmental pedicle screw instrumentation with hybrid constructs in adolescent idiopathic scoliosis (AIS).

METHODSStudy the clinical data of 40 AIS patients retrospectively. They were underwent posterior fusion and be distributed into two group, group A was hybrid instrumentation (20 cases) and group B was pedicle screw instrumentation (20 cases). Compared therapy effect, operative time, intraoperative blood loss.

RESULTSThe average major curve correction was 82.4% in the screw group and 71.8% in the hybrid group (P = 0.004). After one to three years follow-up, major curve correction was 77.0% and 62.5% respectively (P = 0.001). Average apical vertebral derotation showed 63% correction in the screw group and 32% in the hybrid group (P = 0.001). There was no statistical significance between two group in thoracic sagittal correction, the lowest instrumented vertebra below the lower end vertebra, trunk shift, operative time, and average estimated blood loss. There were no neurologic complications related to hybrid or pedicle screw instrumentation.

CONCLUSIONPedicle screw instrumentation was significantly better than hybrid constructs.

Adolescent ; Adult ; Bone Nails ; Bone Screws ; Child ; Female ; Follow-Up Studies ; Humans ; Male ; Retrospective Studies ; Scoliosis ; surgery ; Spinal Fusion ; instrumentation ; methods ; Treatment Outcome