Anterior Lumbar Spine Surgery Research Articles

Chyloretroperitoneum following anterior spinal deformity correction

✓ Chyloretroperitoneum is an uncommon complication following spinal surgery. The authors present the case of a patient in whom conservative treatment and initial surgical measures failed to relieve varied symptoms of postsurgical chyloretroperitoneum. Following attempts at conservative management, a peritoneal window was surgically created to divert lymphatic flow from the retroperitoneal space into the peritoneal space, where it was resorbed. This unique surgical technique provides yet another option in the treatment of refractory chyloretroperitoneum following anterior lumbar spinal surgery. The authors describe their technique and review retroperitoneal lymphatic anatomy along with similar case reports in the literature.

Spontaneous healing of retroperitoneal chylous leakage following anterior lumbar spinal surgery: a case report and literature review

Cisterna chyli is prone to injury in any retroperitoneal surgery. However, retroperitoneal chylous leakage is a rare complication after anterior spinal surgery. To the best of our knowledge, only ten cases have been reported in the English literature. We present a case of a 49-year-old man who had lumbar metastasis and associated radiculopathy. He had transient retroperitoneal chylous leakage after anterior tumor decompression, interbody bony fusion, and instrumental fixation from L2 to L4. The leakage stopped spontaneously after we temporarily clamped the drain tube. Intraperitoneal ascites accumulation developed thereafter due to nutritional loss and impaired hepatic reserves. We gathered ten reported cases of chylous leak after anterior thoracolumbar or lumbar spinal surgery, and categorized all these cases into two groups, depending on the integrity of diaphragm. Six patients received anterior spinal surgery without diaphragm splitting. Postoperative chylous leak stopped after conservative treatment. Another five cases received diaphragm splitting in the interim of anterior spinal surgery. Chylous leakage stopped spontaneously in four patients. The remaining one had a chylothorax secondary to postop chyloretroperitoneum. It was resolved only after surgical intervention. In view of these cases, all the chylous leakage could be spontaneously closed without complications, except for one who had a secondary chylothorax and required thoracic duct ligation and chemopleurodesis. We conclude that intraoperative diaphragm splitting or incision does not increase the risk of secondary chylothorax if it was closed tightly at the end of the surgery and the chest tube drainage properly done.

Use of rhBMP-2 in Combination With Structural Cortical Allografts: Clinical and Radiographic Outcomes in Anterior Lumbar Spinal Surgery

Use of rhBMP-2 in Combination With Structural Cortical Allografts: Clinical and Radiographic Outcomes in Anterior Lumbar Spinal Surgery

Use of rhBMP-2 in Combination with Structural Cortical Allografts: Clinical and Radiographic Outcomes in Anterior Lumbar Spinal Surgery

Recombinant human bone morphogenetic protein-2 soaked into an absorbable collagen sponge (rhBMP-2/ACS) has been shown in a nonhuman primate study and in a pilot study in humans to promote new bone formation and incorporation of an allograft device when implanted in patients undergoing anterior lumbar interbody arthrodesis. However, a larger series with longer follow-up is needed to demonstrate its superiority to autogenous iliac crest bone graft. Between 1998 and 2001, a two-part, prospective, randomized, multicenter study of 131 patients was conducted to determine the safety and efficacy of the use of rhBMP-2/ACS as a replacement for autogenous iliac crest bone graft in anterior lumbar spinal arthrodesis with threaded cortical allograft dowels. Patients were randomly assigned to a study group that received rhBMP-2/ACS or to a control group that received autograft. The clinical and radiographic outcomes were determined with use of well-established instruments and radiographic assessments. The patients in the study group had significantly better outcomes than the control group with regard to the average length of surgery (p < 0.001), blood loss (p < 0.001), and hospital stay (p = 0.020). Fusion rates were significantly better in the study group (p < 0.001). The average Oswestry Disability Index scores, Short-Form-36 physical component summary scores, and low-back and leg-pain scores were significantly better in the study group (p < 0.05). In patients undergoing anterior lumbar interbody arthrodesis with threaded allograft cortical bone dowels, rhBMP-2/ACS was an effective replacement for autogenous bone graft and eliminated the morbidity associated with graft harvesting.

Nerve monitoring changes related to iliac artery compression during anterior lumbar spine surgery

BACKGROUND CONTEXT: There are no studies in the literature that correlate compression of the iliac vessels resulting in obstruction of blood flow with changes in nerve monitoring parameters during anterior lumbar surgery. PURPOSE: To determine whether there is significant compression of the iliac vessels that can cause temporary nerve root ischemia or limb ischemia that could be responsible for loss of somatosensory evoked potentials (SSEP) while retractors are in place for exposure during anterior lumbar interbody fusion (ALIF). SETTING: Patients coming to the operating room for ALIF from levels L2–L3 to L5–S1 would be studied for nerve monitoring changes during the procedure with particular attention to the intervals just before placement of a retractor, while the retractor was in place and immediately after removal of the retractor. PATIENT SAMPLE: Forty-five consecutive patients were studied for changes in SSEP and oxygen saturation (SaO 2) while undergoing ALIF. OUTCOME MEASURES: Patients were considered to have lost saturation if the SaO 2 decreased to below 90%. Patients were considered to have abnormal SSEP with any increase in latency and decrease in amplitude. METHODS: SSEP and SaO 2 were monitored continuously and simultaneously before exposure of the disc spaces, during exposure with retractors in place and after removal of the retractors. RESULTS: Thirteen of 23 patients with exposure at L4–L5 had both loss of SSEP signals and loss of SaO 2 with exposure. All 13 patients had return to normal saturation and recovery of the SSEP signals within 15 minutes of removal of the retractors. Both of these are significant correlations (p<.001). CONCLUSION: This study showed that the majority (57%) of patients undergoing ALIF at the L4–L5 level are subject to compression of the left iliac vessels enough to cause desaturation distally as measured by pulse oxymetry. This vascular compromise, as well as the return to normal saturation, correlates with changes noted in SSEP soon after both deployment and removal of the retractors used for exposure. The mechanism appears to be a transient ischemic response. Failure of the SSEP signals to recover may be diagnostic of left iliac artery thrombosis.

Minimally invasive retroperitoneal approach for lumbar corpectomy and anterior reconstruction

The anterior decompressive procedure in which spinal fusion is performed is considered an effective treatment for thoracolumbar fractures and tumors. However, it is also known to be associated with considerable surgery-related trauma. The purpose of this study was to show that lumbar corpectomy and anterior reconstruction can be performed via a minimally invasive retroperitoneal approach (MIRA) and therefore the surgical approach-related trauma can be reduced. The authors studied retrospectively the hospital records and radiological studies obtained in five patients (mean age 67.4 years, range 59-76 years) who underwent lumbar corpectomy and spinal fusion via an MIRA followed by posterior fixation. Four patients presented with osteoporotic compression fractures at L-2 and L-3, and one patient presented with metastatic disease in L-4 from prostate cancer. Neurological deficits due to cauda equina compression were demonstrated in all patients. The MIRA provided excellent exposure to facilitate complete decompression and anterior reconstruction in all patients, as verified on follow-up radiographic studies. All patients improved clinically. A 1-year follow-up record is available for four patients and a 6-month follow-up record for the fifth patient; continuing clinical improvement has been observed in all. Radiography demonstrated anatomically correct reconstruction in all patients, as well as a solid fusion or a stable compound union in the four patients for whom 1-year follow-up records were available. The MIRA allows the surgeon to perform anterior lumbar spine surgery via a less invasive approach. The efficacy and safety of this technique and its potential to reduce perioperative morbidity compared with conventional retroperitoneal lumbar spine surgery should be further investigated in a larger series.

Minimally invasive retroperitoneal approach for lumbar corpectomy and reconstruction

Anterior decompressive surgery with spinal fusion is considered an effective treatment for thoracolumbar fractures and tumors. However, it is also known to be associated with considerable surgical approach–related trauma. The purpose of this study was to show that lumbar corpectomy and spinal reconstruction can be performed via a minimally invasive retroperitoneal (MIR) approach and therefore, the surgical approach–related trauma can be reduced. The hospital records and radiological studies obtained in five patients (mean age 67.4 years, range 59-76 years) who underwent lumbar corpectomy and spinal fusion via an MIR approach were studied retrospectively. Four patients presented with osteoporotic compression fractures at L-2 and L-3 and one patient with metastatic disease at L-4 from prostate cancer. In all patients neurological deficits due to cauda equina compression were demonstrated. The MIR approach provided excellent exposure to facilitate complete spinal decompression and reconstruction in all patients, as verified on follow-up x-ray studies. All patients improved clinically. A 1-year follow-up record, available for four patients, showed evidence of continuing clinical improvement and, radiographically, a solid fusion or a stable compound union and anatomically correct reconstruction. The MIR approach allows anterior lumbar spine surgery to be performed less invasively. The efficacy and safety of this technique compared with the conventional retroperitoneal approach to lumbar spine surgery should be further investigated in a larger series.