J Huazhong Univ Sci Technol [Med Sci] 33(5):707-712,2013 10. 10.1007/s11596-013-1184-x J DOI Huazhong Univ Sci Technol [Med Sci] 33(5):2013
707
Single-level Lumbar Pyogenic Spondylodiscitis Treated with Minimally Invasive Anterior Debridement and Fusion Combined with Posterior Fixation via Wiltse Approach* Yang LIN (林 阳), Wen-jian CHEN (陈文坚), Wen-tao ZHU (祝文涛), Feng LI (李 锋), Huang FANG (方 煌), An-min CHEN (陈安民), Wei XIONG (熊 伟)# Department of Orthopedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China © Huazhong University of Science and Technology and Springer-Verlag Berlin Heidelberg 2013
Summary: The effect and safety of anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach were assessed in the single-level lumbar pyogenic spondylodiscitis. Seventeen patients from 2007 to 2009 underwent anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach. Postoperative follow-up time was 24–41 months. Data included the patients’ general information, microbiology, operative time, intraoperative blood loss, postoperative complications, intervertebral fusion rate, and preoperative and final follow-up scores for American Spinal Injury Association (ASIA) impairment, visual analogue scale (VAS), and Oswestry Disability Index (ODI). Ten patients had undergone a prior spinal invasive procedure, and 7 had hematogenous infection. The infected segments included L1-2, L2-3, L3-4, and L4-5 in 1, 2, 5, and 9 cases, respectively. Thirteen bacterial cultures were positive for Staphylococcus aureus (5 cases), Staphylococcus epidermidis (4), Streptococcus (3), and Escherichia coli (1). The operative time was 213.8±45.6 min, and the intraoperative blood loss was 180.6±88.1 mL. Postoperative complications consisted of urinary retention (2 cases), constipation (3), and deep vein thrombosis (2). On the final follow-up, VAS scores and ODIs were significantly lower than those of preoperation, while the ASIA grades improved. All the cases achieved good intervertebral bony fusion. Anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach can successfully treat single-level lumbar pyogenic spondylodiscitis, with less trauma and reliable immobilization. It is a viable option for clinical application. Key words: lumbar pyogenic spondylodiscitis; minimal invasion; Wiltse approach; curative effect
Lumbar pyogenic spondylodiscitis has a low incidence rate, but its onset is typically acute and accompanied by severe symptoms and consequences. The inflammation of the intervertebral disc space and adjacent vertebra that defines this condition can occur after lumbar intervertebral disc surgery and invasive procedures[1], or it can be hematogenous[2]. Conservative treatment is generally preferred[3–5], but surgery is recommended for patients with spinal deformity, epidural abscess, neurological deficit, or conservative treatment failure[5–7]. Surgical treatment is applied for debridement, nerve decompression, and the correction of deformity. Internal fixation is usually implemented to maintain local mechanical stability and create a suitable environment for removal of inflammation and bony fusion. Anterior debridement and fusion combined with posterior fixation[8] are most widely used and they provide thorough debridement and reliable fixation[9]. However, conventional lumbar anterior debridement[10] and the posterior midline approach have serious inadequacies, including Yang LIN, E-mail: [email protected] # Corresponding author, E-mail: [email protected] * This project was supported by Hubei Provincial Natural Science Foundation of China (No. 2012FFB02322).
great surgical trauma, bleeding, and a high rate of complications. New surgical methods are needed in order to improve patient outcome and decrease complications. From 2007 to 2009, 17 patients with single-level lumbar pyogenic spondylodiscitis were surgically treated in our hospital by using anterior debridement and fusion via a minimally invasive approach, combined with posterior fixation through the Wiltse approach[11]. The present study is a retrospective assessment of the safety of the procedure and the patient outcome. All patients were followed up for at least 24 months and the clinical outcomes were satisfactory. 1 MATERIALS AND METHODS 1.1 Clinical Data From July 2007 to December 2009, 17 patients (10 men and 7 women; aged 49.2±9.7 years, range: 30–67 years) with single-level lumbar pyogenic spondylodiscitis in our hospital were treated by anterior debridement and fusion via a minimally invasive approach, combined with posterior fixation through the Wiltse approach. There were 10 cases of postoperative infection resulting from an invasive procedure for lumbar disc herniation: ozone ablation in 2 cases, laser ablation in one case, radiofrequency ablation in 2 cases, chemonu-
708 cleolysis in one case, and cutting-aspiration of the nucleus pulposus in 4 cases. Hematogenous infection occurred in the remaining 7 cases. The preoperative examination included blood routine tests: white blood cell (WBC) counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and blood culture. Imaging studies consisted of lumbar posterior-anterior and flexion-extension X-ray, lumbar computed tomography (CT) and magnetic resonance imaging (MRI) (fig. 1). Single-level lumbar pyogenic spondylodiscitis was diagnosed for all patients: L1-2 in 1 case, L2-3 in 2, L3-4 in 5, and L4-5 in 9.
Fig. 1 Representative preoperative MRI showing lumbar pyogenic spondylodiscitis
The diagnosis of lumbar pyogenic spondylodiscitis was based on preoperative clinical presentation, laboratory examination, radiological imaging, blood culture, biopsy, and culture of the specimen obtained during surgery. Indications for surgery were neurological deficit and non-surgical treatment failure. 1.2 Surgical Procedure Under general anesthesia, posterior pedicle screw fixation was performed first through the Wiltse approach, which revealed the facet joints through multifidus muscle lateral gaps. Pedicle screws were implanted in the proximal and distal vertebrae of the affected segment. If the distal vertebra was more than 50% destroyed, then fixation extended one segment further. Two pre-bent titanium rods of suitable physiological curvature were connected to the screws, and the end caps were tightened to immobilize the affected segment. The patients were turned to the right lateral position, and the incision level and surface markers were confirmed by C-arm fluoroscopy. A minimally invasive incision (≤5 cm) was performed from the left intervertebral horizontal lines and through the external oblique, internal oblique, and transverse abdominal muscles and retroperitoneal space. By pushing the retroperitoneal fat forward the psoas muscle was directly visible. After reconfirming the position, the psoas was longitudinally separated directly to reveal the affected intervertebral space. We performed a minimally invasive distraction using a Medtronic EndoRing (fig. 2) to establish a working channel, which provided a clear visual field of the affected space for the surgeon.
J Huazhong Univ Sci Technol [Med Sci] 33(5):2013
Fig. 2 EndoRing distraction device used to establish a working channel
After cutting open the annulus, pus and tissue in the intervertebral space were collected for a bacterial culture and drug sensitivity test. All the visible necrotic tissue, nucleus pulposus, endplate cartilage, and sequestra were scraped thoroughly. The intervertebral space was profusely rinsed with 3% hydrogen peroxide and povidone iodine saline. The sterile surgical instrument was replaced, and an autologous iliac bone strut was removed and trimmed to the appropriate size. It was then implanted into the intervertebral space and was suppressed firmly. One irrigation pipe and one drainage pipe were placed in the intervertebral space, with another drainage pipe placed extraperitoneally. 1.3 Perioperative Treatment Broad-spectrum intravenous antibiotics were administered soon after diagnosis of lumbar pyogenic spondylodiscitis, till ≥4 weeks postoperatively. Antibiotics were used continuously at least two weeks after the disappearance of symptoms and signs and until the WBC count, ESR, and CRP returned to normal. Antibiotics were adjusted based on results of the drug sensitivity test. Postoperative gentamicin-saline irrigation in the lesion area continued at least 3 weeks, and was not stopped until continuous culture of drainage liquid tested negative 3 times. The patients were directed to maintain strict postoperative bed rest for no less than four weeks and were instructed to exercise lower limbs and back muscles in bed. When the symptoms and signs were relieved, ambulation was permitted under the protection of a waist belt. Lower extremity vascular ultrasound examination was performed 10 days postoperatively. 1.4 Therapeutic Evaluation Patients’ symptoms and signs were evaluated after surgery. Lumbar X-rays were examined at 3rd and 6th month to confirm intervertebral fusion. WBC count, ESR and CRP were reviewed weekly until the results returned to normal. Preoperative and postoperative (follow-up) assessments of spinal cord injury, pain, and disability were conducted using the American Spinal Injury Association (ASIA) impairment classification[12], visual analog scale (VAS) score[13], and Oswestry disability index (ODI)[14], respectively. Postoperative complications were monitored during the follow-up period. 1.5 Statistical Analysis Statistical analyses were performed using SPSS 16.0 software for Windows. The paired t-test was used for comparing VAS scores and ODIs between the preoperation and final follow-up. P
707
Single-level Lumbar Pyogenic Spondylodiscitis Treated with Minimally Invasive Anterior Debridement and Fusion Combined with Posterior Fixation via Wiltse Approach* Yang LIN (林 阳), Wen-jian CHEN (陈文坚), Wen-tao ZHU (祝文涛), Feng LI (李 锋), Huang FANG (方 煌), An-min CHEN (陈安民), Wei XIONG (熊 伟)# Department of Orthopedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China © Huazhong University of Science and Technology and Springer-Verlag Berlin Heidelberg 2013
Summary: The effect and safety of anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach were assessed in the single-level lumbar pyogenic spondylodiscitis. Seventeen patients from 2007 to 2009 underwent anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach. Postoperative follow-up time was 24–41 months. Data included the patients’ general information, microbiology, operative time, intraoperative blood loss, postoperative complications, intervertebral fusion rate, and preoperative and final follow-up scores for American Spinal Injury Association (ASIA) impairment, visual analogue scale (VAS), and Oswestry Disability Index (ODI). Ten patients had undergone a prior spinal invasive procedure, and 7 had hematogenous infection. The infected segments included L1-2, L2-3, L3-4, and L4-5 in 1, 2, 5, and 9 cases, respectively. Thirteen bacterial cultures were positive for Staphylococcus aureus (5 cases), Staphylococcus epidermidis (4), Streptococcus (3), and Escherichia coli (1). The operative time was 213.8±45.6 min, and the intraoperative blood loss was 180.6±88.1 mL. Postoperative complications consisted of urinary retention (2 cases), constipation (3), and deep vein thrombosis (2). On the final follow-up, VAS scores and ODIs were significantly lower than those of preoperation, while the ASIA grades improved. All the cases achieved good intervertebral bony fusion. Anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach can successfully treat single-level lumbar pyogenic spondylodiscitis, with less trauma and reliable immobilization. It is a viable option for clinical application. Key words: lumbar pyogenic spondylodiscitis; minimal invasion; Wiltse approach; curative effect
Lumbar pyogenic spondylodiscitis has a low incidence rate, but its onset is typically acute and accompanied by severe symptoms and consequences. The inflammation of the intervertebral disc space and adjacent vertebra that defines this condition can occur after lumbar intervertebral disc surgery and invasive procedures[1], or it can be hematogenous[2]. Conservative treatment is generally preferred[3–5], but surgery is recommended for patients with spinal deformity, epidural abscess, neurological deficit, or conservative treatment failure[5–7]. Surgical treatment is applied for debridement, nerve decompression, and the correction of deformity. Internal fixation is usually implemented to maintain local mechanical stability and create a suitable environment for removal of inflammation and bony fusion. Anterior debridement and fusion combined with posterior fixation[8] are most widely used and they provide thorough debridement and reliable fixation[9]. However, conventional lumbar anterior debridement[10] and the posterior midline approach have serious inadequacies, including Yang LIN, E-mail: [email protected] # Corresponding author, E-mail: [email protected] * This project was supported by Hubei Provincial Natural Science Foundation of China (No. 2012FFB02322).
great surgical trauma, bleeding, and a high rate of complications. New surgical methods are needed in order to improve patient outcome and decrease complications. From 2007 to 2009, 17 patients with single-level lumbar pyogenic spondylodiscitis were surgically treated in our hospital by using anterior debridement and fusion via a minimally invasive approach, combined with posterior fixation through the Wiltse approach[11]. The present study is a retrospective assessment of the safety of the procedure and the patient outcome. All patients were followed up for at least 24 months and the clinical outcomes were satisfactory. 1 MATERIALS AND METHODS 1.1 Clinical Data From July 2007 to December 2009, 17 patients (10 men and 7 women; aged 49.2±9.7 years, range: 30–67 years) with single-level lumbar pyogenic spondylodiscitis in our hospital were treated by anterior debridement and fusion via a minimally invasive approach, combined with posterior fixation through the Wiltse approach. There were 10 cases of postoperative infection resulting from an invasive procedure for lumbar disc herniation: ozone ablation in 2 cases, laser ablation in one case, radiofrequency ablation in 2 cases, chemonu-
708 cleolysis in one case, and cutting-aspiration of the nucleus pulposus in 4 cases. Hematogenous infection occurred in the remaining 7 cases. The preoperative examination included blood routine tests: white blood cell (WBC) counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and blood culture. Imaging studies consisted of lumbar posterior-anterior and flexion-extension X-ray, lumbar computed tomography (CT) and magnetic resonance imaging (MRI) (fig. 1). Single-level lumbar pyogenic spondylodiscitis was diagnosed for all patients: L1-2 in 1 case, L2-3 in 2, L3-4 in 5, and L4-5 in 9.
Fig. 1 Representative preoperative MRI showing lumbar pyogenic spondylodiscitis
The diagnosis of lumbar pyogenic spondylodiscitis was based on preoperative clinical presentation, laboratory examination, radiological imaging, blood culture, biopsy, and culture of the specimen obtained during surgery. Indications for surgery were neurological deficit and non-surgical treatment failure. 1.2 Surgical Procedure Under general anesthesia, posterior pedicle screw fixation was performed first through the Wiltse approach, which revealed the facet joints through multifidus muscle lateral gaps. Pedicle screws were implanted in the proximal and distal vertebrae of the affected segment. If the distal vertebra was more than 50% destroyed, then fixation extended one segment further. Two pre-bent titanium rods of suitable physiological curvature were connected to the screws, and the end caps were tightened to immobilize the affected segment. The patients were turned to the right lateral position, and the incision level and surface markers were confirmed by C-arm fluoroscopy. A minimally invasive incision (≤5 cm) was performed from the left intervertebral horizontal lines and through the external oblique, internal oblique, and transverse abdominal muscles and retroperitoneal space. By pushing the retroperitoneal fat forward the psoas muscle was directly visible. After reconfirming the position, the psoas was longitudinally separated directly to reveal the affected intervertebral space. We performed a minimally invasive distraction using a Medtronic EndoRing (fig. 2) to establish a working channel, which provided a clear visual field of the affected space for the surgeon.
J Huazhong Univ Sci Technol [Med Sci] 33(5):2013
Fig. 2 EndoRing distraction device used to establish a working channel
After cutting open the annulus, pus and tissue in the intervertebral space were collected for a bacterial culture and drug sensitivity test. All the visible necrotic tissue, nucleus pulposus, endplate cartilage, and sequestra were scraped thoroughly. The intervertebral space was profusely rinsed with 3% hydrogen peroxide and povidone iodine saline. The sterile surgical instrument was replaced, and an autologous iliac bone strut was removed and trimmed to the appropriate size. It was then implanted into the intervertebral space and was suppressed firmly. One irrigation pipe and one drainage pipe were placed in the intervertebral space, with another drainage pipe placed extraperitoneally. 1.3 Perioperative Treatment Broad-spectrum intravenous antibiotics were administered soon after diagnosis of lumbar pyogenic spondylodiscitis, till ≥4 weeks postoperatively. Antibiotics were used continuously at least two weeks after the disappearance of symptoms and signs and until the WBC count, ESR, and CRP returned to normal. Antibiotics were adjusted based on results of the drug sensitivity test. Postoperative gentamicin-saline irrigation in the lesion area continued at least 3 weeks, and was not stopped until continuous culture of drainage liquid tested negative 3 times. The patients were directed to maintain strict postoperative bed rest for no less than four weeks and were instructed to exercise lower limbs and back muscles in bed. When the symptoms and signs were relieved, ambulation was permitted under the protection of a waist belt. Lower extremity vascular ultrasound examination was performed 10 days postoperatively. 1.4 Therapeutic Evaluation Patients’ symptoms and signs were evaluated after surgery. Lumbar X-rays were examined at 3rd and 6th month to confirm intervertebral fusion. WBC count, ESR and CRP were reviewed weekly until the results returned to normal. Preoperative and postoperative (follow-up) assessments of spinal cord injury, pain, and disability were conducted using the American Spinal Injury Association (ASIA) impairment classification[12], visual analog scale (VAS) score[13], and Oswestry disability index (ODI)[14], respectively. Postoperative complications were monitored during the follow-up period. 1.5 Statistical Analysis Statistical analyses were performed using SPSS 16.0 software for Windows. The paired t-test was used for comparing VAS scores and ODIs between the preoperation and final follow-up. P
