IDC-P in RP specimens was an independent risk factor for PFS and CSS and could predict clinical outcomes.

BACKGROUNDThe authors sought to identify treatment‐related factors that influenced survival after surgical treatment for metastatic spinal tumors and to evaluate the relationship between survival and postoperative ambulation time as a factor related to quality of life.METHODSThe medical records of 81 patients with metastatic spinal tumors who underwent palliative surgery at the study institution were assessed. Univariate analysis for factors influencing survival used the Kaplan–Meier log rank statistic and multivariate analysis used the Cox proportional hazards model. The Spearman correlation test was used to analyze the relationship between postoperative ambulation and survival time.RESULTSThe patients had a median age of 59.9 years and a median survival of 10.6 months after surgery. For patients, postoperative ambulatory median survival was 16.5 months and median ambulation time was 13.8 months. By univariate analysis, anatomic site of the primary tumor, postoperative ambulation, and combined adjuvant therapy (chemotherapy plus radiotherapy) were associated with prolonged survival (P < 0.05). Multivariate analysis identified primary site and postoperative ambulatory function as independent predictors of prolonged survival (P < 0.0001). Significant correlations were found between ambulation time and survival time of patients who were able to walk after surgery (P < 0.0001), even in patients with liver (P < 0.05) or lung carcinoma (P < 0.05).CONCLUSIONSThe anatomic site of primary carcinoma and postoperative ambulation were associated with longer survival after palliative surgery for metastatic spinal tumor. When ambulation is attained after surgery, it can be preserved until late in remaining life even when the primary tumor is unfavorable. Palliative surgery for spinal metastasis can improve the quality and quantity of life. Cancer 2003;97:476–84. © 2003 American Cancer Society.DOI 10.1002/cncr.11039

Lymphopenia represents immunodepression status, thus indicating the increased susceptibility to infection, which may lead to the development of postoperative infection. If lymphopenia is diagnosed as early as possible, surgical wound infection can be treated promptly without removing the instruments.

To reconstruct highly destructed unstable rheumatoid arthritis (RA) cervical lesions, the authors have been using C1/2 transarticular and cervical pedicle screw fixations. Pedicle screw fixation and C1/2 transarticular screw fixation are biomechanically superior to other fixation techniques for RA patients. However, due to severe spinal deformity and small anatomical size of the vertebra, including the lateral mass and pedicle, in the most RA cervical lesions, these screw fixation procedures are technically demanding and pose the potential risk of neurovascular injuries. The purpose of this study was to evaluate the accuracy and safety of cervical pedicle screw insertion to the deformed, fragile, and small RA spine lesions using computer-assisted image-guidance systems. A frameless, stereotactic image-guidance system that is CT-based, and optoelectronic was used for correct screw placement. A total of 21 patients (16 females, 5 males) with cervical disorders due to RA were surgically treated using the image-guidance system. Postoperative computerized tomography and plane X-ray was used to determine the accuracy of the screw placement. Neural and vascular complications associated with screw insertion and postoperative neural recovery were evaluated. Postoperative radiological evaluations revealed that only 1 (2.1%; C4) of 48 screws inserted into the cervical pedicle had perforated the vertebral artery canal more than 25% (critical breach). However, no neurovascular complications were observed. According to Ranawat's classification, 9 patients remained the same, and 12 patients showed improvement. Instrumentation failure, loss of reduction, or nonunion was not observed at the final followup (average 49.5 months; range 24-96 months). In this study, the authors demonstrated that image-guidance systems could be applied safely to the cervical lesions caused by RA. Image-guidance systems are useful tools in preoperative planning and in transarticular or transpedicular screw placement in the cervical spine of RA patients.

Running Head: Accuracy of Multilevel RegistrationAccuracy of Single-time, Multilevel Registration MINI ABSTRACTAccuracy of multilevel registration for skip pedicle screw placement during image-guided, computer-assisted spine surgery, in adolescent idiopathic scoliosis was assessed. Mean surgical time: 310 min. Pedicle violation observed in only 4/265 screws (1.5%). Mean registration error after point merge: 1.69±0.52: after surface merge 0.51±0.16. Multilevel registration may decrease operative time without compromising accuracy of pedicle screw placement. Accuracy of Multilevel Registration KEY POINTS Multilevel registration employs more than 6 registration points for two, three or four consecutive vertebra to shorten the surgical time.  Pedicle violation was observed in 1.5% of inserted screws.  Multilevel registration may decrease operative time without compromising accuracy of pedicle screw placement afforded by this technique in the setting of adolescent idiopathic scoliosis.  Mean correction rate of skip pedicle screw instrumentation was 66.2%. Accuracy of Multilevel Registration STRUCTURED ABSTRACTStudy Design: Retrospective clinical study. Objective: To assess the accuracy of multilevel registration for skip pedicle screw placement during image-guided, computer-assisted spine surgery, in the setting of adolescent idiopathic scoliosis (AIS). Summary of background data: Computerized frameless stereotactic image-guidance has been used recently to improve pedicle screw placement accurately and safety during spine surgery. Because of possible intervertebral motion and usual difference in patients' position between preoperative imaging and surgery, the imaging model and the surgically exposed spine may be significantly discordant. Consequently, current protocols suggested separate registration of each spinal level (single-level registration) before respective pedicle screw placement, a timeconsuming process. Moreover, although multilevel registration for lumbar spine has been reported, that for thoracic spine has not. Methods: Nineteen patients (1 male, and 18 females; mean age, 13.9 years) with AIS who underwent multilevel registration for skip pedicle screw placement were included. Variables including surgical time, blood loss, preoperative and 2-year post-operative Cobb angle, correction rate, and post-operative screw position by CT image were evaluated. Mean registration error (MRE) after point merge and again after surface merge were recorded for each consecutive vertebra of each case. Results: Mean surgical time was 310 min. (range, 168-420 min.). Mean blood loss 1138 g (range, 300-2300 g). Cobb angle before operation and at 2 years post-operation was 62.4 (43-100) degrees and 21.6 (9-42) degrees, respectively. Mean correction rate 66.2% (39.7-84.5%). Total 265 screws were inserted with CT-based navigation system. Pedicle violation was observed in only 4 screws (1.5%). No neurovascular complication occurred. After point merge, average MRE of all cases was 1.69±0.52mm, and after surface merge was 0.51...

Careful insertion of pedicle screws is necessary, especially at C3 to C5, even when using a CT-based navigation system. Pedicle screws tend to be laterally perforated.

Study DesignMulticenter analysis of two groups of patients surgically treated for degenerative L4 unstable spondylolisthesis.PurposeTo compare the clinical and radiographic outcomes of posterolateral fusion (PLF) and posterior lumbar interbody fusion (PLIF) for degenerative L4 unstable spondylolisthesis.Overview of LiteratureSurgery for lumbar degenerative spondylolisthesis is widely performed. However, few reports have compared the outcome of PLF to that of PLIF for degenerative L4 unstable spondylolisthesis.MethodsPatients with L4 unstable spondylolisthesis with Meyerding grade II or more, slip of >10° or >4 mm upon maximum flexion and extension bending, and posterior opening of >5 degree upon flexion bending were studied. Patients were treated from January 2008 to January 2010. Patients who underwent PLF (n=12) and PLIF (n=19) were followed-up for >2 years. Radiographic findings and clinical outcomes evaluated by the Japanese Orthopaedic Association (JOA) score were compared between the two groups. Radiographic evaluation included slip angle, translation, slip angle and translation during maximum flexion and extension bending, intervertebral disc height, lumbar lordotic angle, and fusion rate.ResultsJOA scores of the PLF group before surgery and at final follow-up were 12.3±4.8 and 24.1±3.7, respectively; those of the PLIF group were 14.7±4.8 and 24.2±7.8, respectively, with no significant difference between the two groups. Correction of slip estimated from postoperative slip angle, translation, and maintenance of intervertebral disc height in the PLIF group was significantly (p<0.05) better than those in the PLF group. However, there was no significant difference in lumbar lordotic angle, slip angle and translation angle upon maximum flexion, or extension bending. Fusion rates of the PLIF and PLF groups had no significant difference.ConclusionsThe L4–L5 level posterior instrumented fusion for unstable spondylolisthesis using both PLF and PLIF could ameliorate clinical symptoms when local stability is achieved.

Background:Different perforation rates for cervical pedicle screws by disease are expected in relation to bone quality and pedicle morphology; however, no report comparing pedicle screw perforation rate by disease had previously been published. This study investigated the perforation rates of pedicle screws inserted to cervical pedicle by disease and vertebral level using a CT-based navigation system.Materials/Methods:Fifty-three patients who underwent cervical pedicle screw insertion using CT based navigation system were studied. Diseases included rheumatoid arthritis (RA) (24 cases), destructive spondyloarthropathy (DSA) (10), cervical spondylotic myelopathy (CSM) (9), spine tumor (6), and cervical spondylotic myelopathy associated with athetoid cerebral palsy (CP) (4). Screw perforation rates for cervical pedicle screws were studied. Major perforation was defined as perforation 50% of screw diameter or more.Results:Major perforation rate by disease from C3 to C7 was as follows: spine tumor (0/24, 0%), RA (2/59, 3.4%), DSA (3/65, 4.6%), CP (2/20, 10.0%), and CSM (6/40, 15.0%). There were no clinically important complications such as vertebra arterial injury, spinal cord injury, or nerve root injury caused by any screw perforation. Major perforation rate by vertebral level was: C2(2/30, 6.7%), C3(4/49, 8.2%), C4(6/43, 14.0%), C5(1/32, 3.1%), C6(1/41, 2.4%), and C7(1/45, 2.2%), showing highest rate for C4, followed by C3.Conclusions:Cervical pedicle screw perforation rate by disease was higher in CSM compared to RA and DSA. The perforation rate by vertebral level was higher for C4 and C3, in this order.