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Kozo Sato - One of the best experts on this subject based on the ideXlab platform.
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influence of bone mineral density on pedicle Screw fixation a study of pedicle Screw fixation augmenting posterior lumbar interbody fusion in elderly patients
The Spine Journal, 2001Co-Authors: Koichiro Okuyama, Mitzuho Chiba, Yasuki Tamura, Eiji Abe, Tetsuya Suzuki, Kozo SatoAbstract:Abstract Background context: Some biomechanical studies have demonstrated that bone mineral density of the lumbar spine (BMD) affects the stability of pedicle Screws in vitro. Purpose: To investigate influence of BMD on Loosening and related failure of pedicle Screws in vivo. Study design/setting: A clinical study of 52 patients who underwent pedicle Screw fixation augmenting posterior lumbar interbody fusion (PLIF). Patient sample: There were 13 men and 39 women, with an average age of 63 years (range, 45–76 years) at the time of operation. The mean follow-up period was 2.8 years (range, 2–6 years). Outcome measures: Relationship between BMD, Screw Loosening, and its related failures were statistically analyzed. Methods: BMD was measured by the dual energy X-ray absorptiometry (DEXA) method. Radiographic assessments were done by the first author and independently by another orthopedist who was not informed of the values of BMD. Results: The mean BMD of all patients was 0.879±0.215 (mean±S.D.) g/cm 2 . The mean BMD in patients with and without Screw Loosening was 0.720±0.078 g/cm 2 (n=11) and 0.922±0.221 g/cm 2 (n=41). There was a significant difference between the mean BMD of patients with and without Screw Loosening ( P 2 (n=40), 0.674±0.104 g/cm 2 (n=4) and 0.710±0.116 g/cm 2 (n=8), respectively. The mean BMD of patients with "union" was significantly greater than those with "nonunion" and "undetermined union" ( P Conclusion: It could be concluded that BMD has a close relation with the stability of pedicle Screws in vivo, and BMD value below 0.674±0.104 g/cm 2 suggests a potential increased risk of "nonunion" when pedicle Screw fixation is performed in conjunction with PLIF.
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Can Insertional Torque Predict Screw Loosening and Related Failures? : An In Vivo Study of Pedicle Screw Fixation Augmenting Posterior Lumbar Interbody Fusion
Spine, 2000Co-Authors: Koichiro Okuyama, Mitzuho Chiba, Yasuki Tamura, Eiji Abe, Tetsuya Suzuki, Kozo SatoAbstract:Study Design. An investigation of the relation between intraoperative insertional torque of pedicle Screws, bone mineral density of the vertebra, and development of Screw Loosening in vivo. Objectives. To determine the usefulness of intraoper ative measurement of the insertional torque of pedicle Screws. Summary of Background Data. Some biomechanical studies nave demonstrated that the insertional torque is highly correlated with bone mineral density and the stability of pedicie Screws in vitro. Methods. Pedicle Screw fixation was performed with posterior lumbar interbody fusion in 62 consecutive patients. The mean age of the patients at the time of surgery was 58 years. The insertional torque of pedicle Screws was measured intraoperatively in ail patients. The mean follow-up period was 2.7 years. Results. The mean insertional torque was 1.28 ± 0.37 Nm in patients with Screw Loosening and 1.50 ± 0.40 Nm in patients without the problem. The mean insertional torque in patients with compression fractures in the upper vertebra adjacent to the fixed segment was 0.83 ± 0.23 Nm. There was no significant difference between the mean insertional torque in patients with Screw Loosening and those without the condition. The mean insertional torque in patients without Screw Loosening was significantly greater than in patients with compression fractures (P< 0.01). A high correlation was found between insertional torque and bone mineral density (P< 0.01). Conclusions. Although a high correlation was found between the insertional torque of pedicle Screws andbone mineral density in vivo, the insertional torque could not objectively predict Screw Loosening.
Koichiro Okuyama - One of the best experts on this subject based on the ideXlab platform.
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influence of bone mineral density on pedicle Screw fixation a study of pedicle Screw fixation augmenting posterior lumbar interbody fusion in elderly patients
The Spine Journal, 2001Co-Authors: Koichiro Okuyama, Mitzuho Chiba, Yasuki Tamura, Eiji Abe, Tetsuya Suzuki, Kozo SatoAbstract:Abstract Background context: Some biomechanical studies have demonstrated that bone mineral density of the lumbar spine (BMD) affects the stability of pedicle Screws in vitro. Purpose: To investigate influence of BMD on Loosening and related failure of pedicle Screws in vivo. Study design/setting: A clinical study of 52 patients who underwent pedicle Screw fixation augmenting posterior lumbar interbody fusion (PLIF). Patient sample: There were 13 men and 39 women, with an average age of 63 years (range, 45–76 years) at the time of operation. The mean follow-up period was 2.8 years (range, 2–6 years). Outcome measures: Relationship between BMD, Screw Loosening, and its related failures were statistically analyzed. Methods: BMD was measured by the dual energy X-ray absorptiometry (DEXA) method. Radiographic assessments were done by the first author and independently by another orthopedist who was not informed of the values of BMD. Results: The mean BMD of all patients was 0.879±0.215 (mean±S.D.) g/cm 2 . The mean BMD in patients with and without Screw Loosening was 0.720±0.078 g/cm 2 (n=11) and 0.922±0.221 g/cm 2 (n=41). There was a significant difference between the mean BMD of patients with and without Screw Loosening ( P 2 (n=40), 0.674±0.104 g/cm 2 (n=4) and 0.710±0.116 g/cm 2 (n=8), respectively. The mean BMD of patients with "union" was significantly greater than those with "nonunion" and "undetermined union" ( P Conclusion: It could be concluded that BMD has a close relation with the stability of pedicle Screws in vivo, and BMD value below 0.674±0.104 g/cm 2 suggests a potential increased risk of "nonunion" when pedicle Screw fixation is performed in conjunction with PLIF.
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Can Insertional Torque Predict Screw Loosening and Related Failures? : An In Vivo Study of Pedicle Screw Fixation Augmenting Posterior Lumbar Interbody Fusion
Spine, 2000Co-Authors: Koichiro Okuyama, Mitzuho Chiba, Yasuki Tamura, Eiji Abe, Tetsuya Suzuki, Kozo SatoAbstract:Study Design. An investigation of the relation between intraoperative insertional torque of pedicle Screws, bone mineral density of the vertebra, and development of Screw Loosening in vivo. Objectives. To determine the usefulness of intraoper ative measurement of the insertional torque of pedicle Screws. Summary of Background Data. Some biomechanical studies nave demonstrated that the insertional torque is highly correlated with bone mineral density and the stability of pedicie Screws in vitro. Methods. Pedicle Screw fixation was performed with posterior lumbar interbody fusion in 62 consecutive patients. The mean age of the patients at the time of surgery was 58 years. The insertional torque of pedicle Screws was measured intraoperatively in ail patients. The mean follow-up period was 2.7 years. Results. The mean insertional torque was 1.28 ± 0.37 Nm in patients with Screw Loosening and 1.50 ± 0.40 Nm in patients without the problem. The mean insertional torque in patients with compression fractures in the upper vertebra adjacent to the fixed segment was 0.83 ± 0.23 Nm. There was no significant difference between the mean insertional torque in patients with Screw Loosening and those without the condition. The mean insertional torque in patients without Screw Loosening was significantly greater than in patients with compression fractures (P< 0.01). A high correlation was found between insertional torque and bone mineral density (P< 0.01). Conclusions. Although a high correlation was found between the insertional torque of pedicle Screws andbone mineral density in vivo, the insertional torque could not objectively predict Screw Loosening.
Peter Vajkoczy - One of the best experts on this subject based on the ideXlab platform.
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high frequency of low virulent microorganisms detected by sonication of pedicle Screws a potential cause for implant failure
Journal of Neurosurgery, 2019Co-Authors: Vincent Prinz, Simon Bayerl, Marcus Czabanka, Johannes Woitzik, Peter Vajkoczy, Nora Renz, Andrej Trampuz, Tobias FingerAbstract:OBJECTIVE Loosening of pedicle Screws is a frequent complication after spinal surgery. Implant colonization with low-virulent microorganisms forming biofilms may cause implant Loosening. However, the clinical evidence of this mechanism is lacking. Here, the authors evaluated the potential role of microbial colonization using sonication in patients with clinical pedicle Screw Loosening but without signs of infection. METHODS All consecutive patients undergoing hardware removal between January 2015 and December 2017, including patients with Screw Loosening but without clinical signs of infection, were evaluated. The removed hardware was investigated using sonication. RESULTS A total of 82 patients with a mean (± SD) patient age of 65 ± 13 years were eligible for evaluation. Of the 54 patients with Screw Loosening, 22 patients (40.7%) had a positive sonication result. None of the 28 patients without Screw Loosening who served as a control cohort showed a positive sonication result (p < 0.01). In total, 24 microorganisms were detected in those 22 patients. The most common isolated microorganisms were coagulase-negative staphylococci (62.5%) and Cutibacterium acnes (formerly known as Propionibacterium acnes) (25%). When comparing only the patients with Screw Loosening, the duration of the previous spine surgery was significantly longer in patients with a positive microbiological result (288 ± 147 minutes) than in those with a negative result (201 ± 103 minutes) (p = 0.02). CONCLUSIONS The low-virulent microorganisms frequently detected on pedicle Screws by using sonication may be an important cause of implant Loosening and failure. Longer surgical duration increases the likelihood of implant colonization with subsequent Screw Loosening. Sonication is a highly sensitive approach to detect biofilm-producing bacteria, and it needs to be integrated into the clinical routine for optimized treatment strategies.
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sacropelvic fixation versus fusion to the sacrum for spondylodesis in multilevel degenerative spine disease
European Spine Journal, 2014Co-Authors: Tobias Finger, Simon Bayerl, Julia Onken, Marcus Czabanka, Johannes Woitzik, Peter VajkoczyAbstract:Retrospective study. For successful multilevel correction and stabilization of degenerative spinal deformities, a rigid basal construct to the sacrum is indispensable. The primary objective of this study was to compare the results of two different sacropelvic fixation techniques to conventional stabilization to the sacrum in patients with multilevel degenerative spine disease. A total of 69 patients with multisegmental fusion surgery (mean number of stabilized functional spinal units: 7.0 ± 3.3) with a minimum of 1-year follow-up were included. 32 patients received fixation to the sacrum (S1), 23 patients received S1 and iliac Screw fixation (iliac) and 14 patients were treated with iliosacral plate fixation (plate). Primary outcome parameters were radiographic outcome concerning fusion in the segment L5–S1, rate of Screw Loosening, back and buttock pain reduction [numeric rating scale for pain evaluation: 0 indicating no pain, 10 indicating the worst pain], overall extent of disability after surgery (Oswestry Disability Index) and the number of complications. The three groups did not differ in body mass index, ASA score, the number of stabilized functional spinal units, duration of surgery, the number of previous spine surgeries, or postoperative complication rate. The incidence of L5–S1 pseudarthrosis after 1 year in the S1, iliac, and plate groups was 19, 0, and 29 %, respectively (p < 0.05 iliac vs. plate). The incidence of Screw Loosening after 1 year in the S1, iliac, and plate groups was 22, 4, and 43 %, respectively (p < 0.05 iliac vs. plate). Average Oswestry scores after 1 year in the S1, iliac, and plate groups were 40 ± 18, 42 ± 20, and 58 ± 18, respectively (p < 0.05 both S1 and iliac vs. plate). The surgical treatment of multilevel degenerative spine disease carries a significant risk for pseudarthrosis and Screw Loosening, mandating a rigid sacropelvic fixation. The use of an iliosacral plate resulted in an inferior surgical and clinical outcome when compared to iliac Screws.
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sacropelvic fixation versus fusion to the sacrum for spondylodesis in multilevel degenerative spine disease
European Spine Journal, 2014Co-Authors: Tobias Finger, Simon Bayerl, Julia Onken, Marcus Czabanka, Johannes Woitzik, Peter VajkoczyAbstract:STUDY DESIGN: Retrospective study. OBJECTIVE: For successful multilevel correction and stabilization of degenerative spinal deformities, a rigid basal construct to the sacrum is indispensable. The primary objective of this study was to compare the results of two different sacropelvic fixation techniques to conventional stabilization to the sacrum in patients with multilevel degenerative spine disease. METHODS: A total of 69 patients with multisegmental fusion surgery (mean number of stabilized functional spinal units: 7.0 ± 3.3) with a minimum of 1-year follow-up were included. 32 patients received fixation to the sacrum (S1), 23 patients received S1 and iliac Screw fixation (iliac) and 14 patients were treated with iliosacral plate fixation (plate). Primary outcome parameters were radiographic outcome concerning fusion in the segment L5-S1, rate of Screw Loosening, back and buttock pain reduction [numeric rating scale for pain evaluation: 0 indicating no pain, 10 indicating the worst pain], overall extent of disability after surgery (Oswestry Disability Index) and the number of complications. RESULTS: The three groups did not differ in body mass index, ASA score, the number of stabilized functional spinal units, duration of surgery, the number of previous spine surgeries, or postoperative complication rate. The incidence of L5-S1 pseudarthrosis after 1 year in the S1, iliac, and plate groups was 19, 0, and 29 %, respectively (p < 0.05 iliac vs. plate). The incidence of Screw Loosening after 1 year in the S1, iliac, and plate groups was 22, 4, and 43 %, respectively (p < 0.05 iliac vs. plate). Average Oswestry scores after 1 year in the S1, iliac, and plate groups were 40 ± 18, 42 ± 20, and 58 ± 18, respectively (p < 0.05 both S1 and iliac vs. plate). CONCLUSION: The surgical treatment of multilevel degenerative spine disease carries a significant risk for pseudarthrosis and Screw Loosening, mandating a rigid sacropelvic fixation. The use of an iliosacral plate resulted in an inferior surgical and clinical outcome when compared to iliac Screws.
Tobias Finger - One of the best experts on this subject based on the ideXlab platform.
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high frequency of low virulent microorganisms detected by sonication of pedicle Screws a potential cause for implant failure
Journal of Neurosurgery, 2019Co-Authors: Vincent Prinz, Simon Bayerl, Marcus Czabanka, Johannes Woitzik, Peter Vajkoczy, Nora Renz, Andrej Trampuz, Tobias FingerAbstract:OBJECTIVE Loosening of pedicle Screws is a frequent complication after spinal surgery. Implant colonization with low-virulent microorganisms forming biofilms may cause implant Loosening. However, the clinical evidence of this mechanism is lacking. Here, the authors evaluated the potential role of microbial colonization using sonication in patients with clinical pedicle Screw Loosening but without signs of infection. METHODS All consecutive patients undergoing hardware removal between January 2015 and December 2017, including patients with Screw Loosening but without clinical signs of infection, were evaluated. The removed hardware was investigated using sonication. RESULTS A total of 82 patients with a mean (± SD) patient age of 65 ± 13 years were eligible for evaluation. Of the 54 patients with Screw Loosening, 22 patients (40.7%) had a positive sonication result. None of the 28 patients without Screw Loosening who served as a control cohort showed a positive sonication result (p < 0.01). In total, 24 microorganisms were detected in those 22 patients. The most common isolated microorganisms were coagulase-negative staphylococci (62.5%) and Cutibacterium acnes (formerly known as Propionibacterium acnes) (25%). When comparing only the patients with Screw Loosening, the duration of the previous spine surgery was significantly longer in patients with a positive microbiological result (288 ± 147 minutes) than in those with a negative result (201 ± 103 minutes) (p = 0.02). CONCLUSIONS The low-virulent microorganisms frequently detected on pedicle Screws by using sonication may be an important cause of implant Loosening and failure. Longer surgical duration increases the likelihood of implant colonization with subsequent Screw Loosening. Sonication is a highly sensitive approach to detect biofilm-producing bacteria, and it needs to be integrated into the clinical routine for optimized treatment strategies.
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sacropelvic fixation versus fusion to the sacrum for spondylodesis in multilevel degenerative spine disease
European Spine Journal, 2014Co-Authors: Tobias Finger, Simon Bayerl, Julia Onken, Marcus Czabanka, Johannes Woitzik, Peter VajkoczyAbstract:Retrospective study. For successful multilevel correction and stabilization of degenerative spinal deformities, a rigid basal construct to the sacrum is indispensable. The primary objective of this study was to compare the results of two different sacropelvic fixation techniques to conventional stabilization to the sacrum in patients with multilevel degenerative spine disease. A total of 69 patients with multisegmental fusion surgery (mean number of stabilized functional spinal units: 7.0 ± 3.3) with a minimum of 1-year follow-up were included. 32 patients received fixation to the sacrum (S1), 23 patients received S1 and iliac Screw fixation (iliac) and 14 patients were treated with iliosacral plate fixation (plate). Primary outcome parameters were radiographic outcome concerning fusion in the segment L5–S1, rate of Screw Loosening, back and buttock pain reduction [numeric rating scale for pain evaluation: 0 indicating no pain, 10 indicating the worst pain], overall extent of disability after surgery (Oswestry Disability Index) and the number of complications. The three groups did not differ in body mass index, ASA score, the number of stabilized functional spinal units, duration of surgery, the number of previous spine surgeries, or postoperative complication rate. The incidence of L5–S1 pseudarthrosis after 1 year in the S1, iliac, and plate groups was 19, 0, and 29 %, respectively (p < 0.05 iliac vs. plate). The incidence of Screw Loosening after 1 year in the S1, iliac, and plate groups was 22, 4, and 43 %, respectively (p < 0.05 iliac vs. plate). Average Oswestry scores after 1 year in the S1, iliac, and plate groups were 40 ± 18, 42 ± 20, and 58 ± 18, respectively (p < 0.05 both S1 and iliac vs. plate). The surgical treatment of multilevel degenerative spine disease carries a significant risk for pseudarthrosis and Screw Loosening, mandating a rigid sacropelvic fixation. The use of an iliosacral plate resulted in an inferior surgical and clinical outcome when compared to iliac Screws.
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sacropelvic fixation versus fusion to the sacrum for spondylodesis in multilevel degenerative spine disease
European Spine Journal, 2014Co-Authors: Tobias Finger, Simon Bayerl, Julia Onken, Marcus Czabanka, Johannes Woitzik, Peter VajkoczyAbstract:STUDY DESIGN: Retrospective study. OBJECTIVE: For successful multilevel correction and stabilization of degenerative spinal deformities, a rigid basal construct to the sacrum is indispensable. The primary objective of this study was to compare the results of two different sacropelvic fixation techniques to conventional stabilization to the sacrum in patients with multilevel degenerative spine disease. METHODS: A total of 69 patients with multisegmental fusion surgery (mean number of stabilized functional spinal units: 7.0 ± 3.3) with a minimum of 1-year follow-up were included. 32 patients received fixation to the sacrum (S1), 23 patients received S1 and iliac Screw fixation (iliac) and 14 patients were treated with iliosacral plate fixation (plate). Primary outcome parameters were radiographic outcome concerning fusion in the segment L5-S1, rate of Screw Loosening, back and buttock pain reduction [numeric rating scale for pain evaluation: 0 indicating no pain, 10 indicating the worst pain], overall extent of disability after surgery (Oswestry Disability Index) and the number of complications. RESULTS: The three groups did not differ in body mass index, ASA score, the number of stabilized functional spinal units, duration of surgery, the number of previous spine surgeries, or postoperative complication rate. The incidence of L5-S1 pseudarthrosis after 1 year in the S1, iliac, and plate groups was 19, 0, and 29 %, respectively (p < 0.05 iliac vs. plate). The incidence of Screw Loosening after 1 year in the S1, iliac, and plate groups was 22, 4, and 43 %, respectively (p < 0.05 iliac vs. plate). Average Oswestry scores after 1 year in the S1, iliac, and plate groups were 40 ± 18, 42 ± 20, and 58 ± 18, respectively (p < 0.05 both S1 and iliac vs. plate). CONCLUSION: The surgical treatment of multilevel degenerative spine disease carries a significant risk for pseudarthrosis and Screw Loosening, mandating a rigid sacropelvic fixation. The use of an iliosacral plate resulted in an inferior surgical and clinical outcome when compared to iliac Screws.
Eiji Abe - One of the best experts on this subject based on the ideXlab platform.
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influence of bone mineral density on pedicle Screw fixation a study of pedicle Screw fixation augmenting posterior lumbar interbody fusion in elderly patients
The Spine Journal, 2001Co-Authors: Koichiro Okuyama, Mitzuho Chiba, Yasuki Tamura, Eiji Abe, Tetsuya Suzuki, Kozo SatoAbstract:Abstract Background context: Some biomechanical studies have demonstrated that bone mineral density of the lumbar spine (BMD) affects the stability of pedicle Screws in vitro. Purpose: To investigate influence of BMD on Loosening and related failure of pedicle Screws in vivo. Study design/setting: A clinical study of 52 patients who underwent pedicle Screw fixation augmenting posterior lumbar interbody fusion (PLIF). Patient sample: There were 13 men and 39 women, with an average age of 63 years (range, 45–76 years) at the time of operation. The mean follow-up period was 2.8 years (range, 2–6 years). Outcome measures: Relationship between BMD, Screw Loosening, and its related failures were statistically analyzed. Methods: BMD was measured by the dual energy X-ray absorptiometry (DEXA) method. Radiographic assessments were done by the first author and independently by another orthopedist who was not informed of the values of BMD. Results: The mean BMD of all patients was 0.879±0.215 (mean±S.D.) g/cm 2 . The mean BMD in patients with and without Screw Loosening was 0.720±0.078 g/cm 2 (n=11) and 0.922±0.221 g/cm 2 (n=41). There was a significant difference between the mean BMD of patients with and without Screw Loosening ( P 2 (n=40), 0.674±0.104 g/cm 2 (n=4) and 0.710±0.116 g/cm 2 (n=8), respectively. The mean BMD of patients with "union" was significantly greater than those with "nonunion" and "undetermined union" ( P Conclusion: It could be concluded that BMD has a close relation with the stability of pedicle Screws in vivo, and BMD value below 0.674±0.104 g/cm 2 suggests a potential increased risk of "nonunion" when pedicle Screw fixation is performed in conjunction with PLIF.
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Can Insertional Torque Predict Screw Loosening and Related Failures? : An In Vivo Study of Pedicle Screw Fixation Augmenting Posterior Lumbar Interbody Fusion
Spine, 2000Co-Authors: Koichiro Okuyama, Mitzuho Chiba, Yasuki Tamura, Eiji Abe, Tetsuya Suzuki, Kozo SatoAbstract:Study Design. An investigation of the relation between intraoperative insertional torque of pedicle Screws, bone mineral density of the vertebra, and development of Screw Loosening in vivo. Objectives. To determine the usefulness of intraoper ative measurement of the insertional torque of pedicle Screws. Summary of Background Data. Some biomechanical studies nave demonstrated that the insertional torque is highly correlated with bone mineral density and the stability of pedicie Screws in vitro. Methods. Pedicle Screw fixation was performed with posterior lumbar interbody fusion in 62 consecutive patients. The mean age of the patients at the time of surgery was 58 years. The insertional torque of pedicle Screws was measured intraoperatively in ail patients. The mean follow-up period was 2.7 years. Results. The mean insertional torque was 1.28 ± 0.37 Nm in patients with Screw Loosening and 1.50 ± 0.40 Nm in patients without the problem. The mean insertional torque in patients with compression fractures in the upper vertebra adjacent to the fixed segment was 0.83 ± 0.23 Nm. There was no significant difference between the mean insertional torque in patients with Screw Loosening and those without the condition. The mean insertional torque in patients without Screw Loosening was significantly greater than in patients with compression fractures (P< 0.01). A high correlation was found between insertional torque and bone mineral density (P< 0.01). Conclusions. Although a high correlation was found between the insertional torque of pedicle Screws andbone mineral density in vivo, the insertional torque could not objectively predict Screw Loosening.
