Pyogenic infections of the lumbar spine are a rare but critical pathology, yet with considerably high mortality rates. In cases indicating surgical therapy, the implantation of titanium cages or autologous bone grafts represent today's gold standard. Although non-metallic implants such as poly-ether-ether-ketone (PEEK) have proven to be advantageous in diverse degenerative conditions, their saftey and practicability in lumbar spine infection remains questionable. Moreover, the efficacy of a single-step radical debridement of the infected disc space with subsequent fusion from a strictly posterior approach continues to be an issue of debate. We therefore sought to evaluate the feasibility, clinical and radiological outcome of a single-step TLIF procedure using oblique PEEK cages in the surgical management of patients with lumbar pyogenic spondylodiscitis.
Methods
From January 2009 through December 2013, all patients meeting the indication for surgical treatment of lumbar pyogenic spondylodiscitis were included. Patients demonstrating intact cortical bone on preoperative CT received a single-step radical debridement of the infected intervertebral disc space, posterior screw-and-rod instrumentation and implantation of an oblique PEEK cage using the TLIF technique. Oral antibiotics were continued for 12 weeks postoperatively and clinical and radiological results recorded throughout a minimum 1-year clinical follow-up.
Results
A total of 104 patients were admitted to receive surgical therapy for lumbar pyogenic spondylodiscitis. Within this patient population, 18 patients met the diagnostic criteria to receive the implantation of an oblique PEEK cage. Pathogens were detected in 13 cases with Staph. aureus being the predominant causative organism. All patients were discharged to recover in their domestic environment. Throughout the first year of clinical and radiological follow-up and beyond, none of the 18 patients demonstrated any signs of residual neurologic deficits or recurrent infection. Furthermore, two-plane conventional X-rays showed no significant implant subsidence or failure at any of the given time-points in up to 5 years postoperatively.
Conclusions
In patients meeting the criteria for surgical treatment of lumbar pyogenic spondylodiscitis, the implantation of PEEK cages using a single-step TLIF approach is a safe and feasible procedure. Based on our experience, the concern of a recurrent infection when implanting non-metallic cages may be refuted in carefully selected patients.
Expandable cages are a more recent option for maintaining or restoring disc height and segmental lordosis with transforaminal lumbar interbody fusion (TLIF). Complications associated with expandable cages have not yet been widely reported. We report a case of postoperative failure of a polyether-ether-ketone (PEEK) expandable interbody device used during TLIF.
Methods
A 50-year-old man presented with severe back and right leg pain after undergoing L4-5 and L5-S1 TLIFs with expandable cages and L3-S1 posterior instrumented fusion. Imaging showed retropulsion of a portion of the interbody cage into the spinal canal causing nerve compression. Displacement occurred in a delayed manner. In addition, pseudoarthrosis was present.
Results
The patient underwent re-exploration with removal of the retropulsed wafer and redo fusion.
Conclusions
Expandable cages are a recent innovation; as such, efficacy and complication data are limited. As with any new device, there exists potential for mechanical failure, as occurred in the case presented.
Aim of the study was to evaluate the biomechanical stability and the clinical efficacy of a lumbar interbody fusion obtained by single oblique cage implanted by a posterior approach.
Method
Through the realization of three finite element models (FEMs), the biomechanics of POLIF was compared to PLIF and TLIF. Ninety-four patients underwent interbody fusion by POLIF with instrumented posterolateral fusion. Clinical and radiographic outcomes were evaluated at regular intervals for at least 6 months.
Results
The FEMs showed no statistically significant differences in stability in compression and flexion–extension. Mean preoperative VAS score was 7.1, decreased to 2.1 at follow-up. Mean preoperative SF-12 value was 34.5 %, increased to 75.4 % at follow-up. All patients showed a good fusion rate and no hardware failure.
Discussion
POLIF associated to instrumented posterolateral fusion is a viable and safe surgical technique, which ensures a biomechanical stability similar to other surgical techniques.
Hidden haemorrhage has been proved to be significant in joint surgery. However, when referring to lumbar interbody fusion, it is often ignored because of its invisibility. This randomized controlled study aimed to calculate and compare hidden haemorrhage following minimally invasive and open transforaminal lumbar interbody fusion (MIS-TLIF and open TLIF). Meanwhile, its clinical significance was also analyzed.
Materials and methods
A total of 41 patients were included in this study, then they were randomized to receive MIS-TLIF or open TLIF, 21 and 20, respectively. For each case, total volume loss of red blood cell (RBC) was calculated by Gross' formula based on perioperative haematocrit change, then perioperative visible volume loss of RBC was calculated through haemorrhage volume and weight. After deducting it from total volume loss of RBC, hidden volume loss of RBC was obtained. Absolute amount of hidden haemorrhage and its ratio upon total haemorrhage, as well as indicators assessing clinical outcomes, including visual analogue scale (VAS) for back and leg, Oswestry disability index (ODI), interbody fusion rate and complication incidence were compared and analyzed.
Results
Mean hidden volume loss of RBC in MIS-TLIF was significantly reduced compared with open TLIF (166.7 versus 245.6 ml). Besides, both mean total and visible volume loss of RBC in MIS-TLIF were also statistically less than those in open TLIF (355.3 versus 538.6 ml; 188.6 versus 293.0 ml). While mean ratio of hidden haemorrhage upon total haemorrhage was 46.7% for MIS-TLIF and 44.5% for open TLIF, respectively, showing no statistical significance. At one week postoperatively, more significant improvements of VAS for back and leg, as well as ODI were seen in MIS-TLIF compared with open TLIF. While at final follow-up of at least 2 years, all parameters continued to improve and revealed no statistical difference between both surgeries. Similar interbody fusion rate and complication incidence were observed in both series.
Conclusions
Besides reduced visible haemorrhage and improved clinical outcomes, MIS-TLIF also owns the superiority of less hidden haemorrhage, offering another advantage over open TLIF.
The aim of the study is to assess and quantify the effectiveness of interbody lordotic cages applied by trans-psoas approach to improve radiographic parameters, showing the differences between completely mini-invasive and hybrid approach.
Methods
We collected data of 65 patients affected by degenerative lumbar deformity/diseases and underwent mini-invasive lateral interbody fusion followed by percutaneous (group A, completely mini-invasive) or open (group B, hybrid) posterior instrumentation. A subgroup underwent anterior column realignment (ACR). We assessed statistical differences in preoperative and postoperative (at least 6-month) coronal and sagittal parameters, and disc angle (DA) at each level of cage application.
Results
107 lordotic cages were implanted. Group B had the most significant mean changes, especially in coronal Cobb angle, sagittal vertical axis, lumbar lordosis (LL), pelvic incidence-LL mismatch and DA. Concerning DA, at each level of lordotic cage application, in group A changed from ?2.9° preop to ?6.5° postop (p = 0.01); in group B, DA changed from ?2.6° to ?9.5° (p = 0.002) and from +1° to ?13.2° in patients underwent ACR.
Conclusions
Minimally invasive lateral lumbar interbody fusion is an effective technique in improving sagittal parameters. When combined with posterior open approach and/or application of ACR procedure greater corrections are possible.
Aged patients represent a high risk group for acquiring spinal tuberculosis, and it still remains a leading cause of kyphosis and paraplegia in developing nations. Aged patients often combined with cardiovascular and respiratory disease and single lung ventilation via anterior approach surgery could result in more post-operative complications. We aimed to analyze the efficacy and feasibility of surgical management of aged patients with lumbo-sacral spine tuberculosis using one-stage posterior focus debridement, interbody graft using titanium mesh cages, posterior instrumentation, and fusion.
Methods
From March 2009 and July 2012, 17 aged patients with lumbo-sacral spinal tuberculosis were treated with one-stage posterior focus debridement, interbody graft using titanium mesh cages, posterior instrumentation, and fusion. There were eight male and nine female with a mean age of 63.3 years (range: 60–71 years). The mean follow-up was 46.5 months (range 38–70 months). Patients were evaluated before and after surgery in terms of ESR, neurological status, visual analog scale (VAS), and lumbosacral angle.
Results
Spinal tuberculosis was completely cured and the grafted bones were fused in all 17 patients. There were no recurrent tuberculous infections. ESR became normal within three months in all patients. The ASIA neurological classification and VAS scores improved in all cases. The average preoperative lumbosacral angle was 20.6° (range 18.1°–22.5°) and became 29.4° (range 27.1°–32.5°) at final follow-up.
Conclusions
Our results showed that one-stage posterior focus debridement, interbody graft using titanium mesh cages, posterior instrumentation, and fusion was an effective treatment for aged patients with lumbo-sacral spinal tuberculosis. It is characterized with minimum surgical trauma, good pain relief, good neurological recovery, and good reconstruction of the spinal stability.
Discectomy and endplate preparation are important steps in interbody fusion for ensuring sufficient arthrodesis. While modern less-invasive approaches for lumbar interbody fusion have gained in popularity, concerns exist regarding their ability to allow for adequate disc space and endplate preparation. Thus, the purpose of this study was to quantitatively and qualitatively evaluate and compare disc space and endplate preparation achieved with four less-invasive approaches for lumbar interbody fusion in cadaveric spines.
Methods
A total of 24 disc spaces (48 endplates) from L2 to L5 were prepared in eight cadaveric torsos using mini-open anterior lumbar interbody fusion (mini-ALIF), minimally invasive posterior lumbar interbody fusion (MAS PLIF), minimally invasive transforaminal lumbar interbody fusion (MAS TLIF) or minimally invasive lateral, transpsoas interbody fusion (XLIF) on two specimens each, for a total of six levels and 12 endplates prepared per procedure type. Following complete discectomy and endplate preparation, spines were excised and split axially at the interbody disc spaces. Endplates were digitally photographed and evaluated using image analysis software. Area of endplate preparation was measured and qualitative evaluation was also performed to grade the quality of preparation.
Results
The XLIF approach resulted in the greatest relative area of endplate preparation (58.3 %) while mini-ALIF resulted in the lowest at 35.0 %. Overall, there were no differences in percentage of preparation between cranial and caudal endplates, though this was significantly different in the XLIF group (65 vs 52 %, respectively). ALL damage was observed in 3 MAS TLIF levels. Percentage of endplate that was deemed to have complete disc removal was highest in XLIF group with 90 % compared to 65 % in MAS TLIF group, 43 % in MAS PLIF, and 40 % in mini-ALIF group. Endplate damage area was highest in the MAS TLIF group at 48 % and lowest in XLIF group at 4 %.
Conclusions
These results demonstrate that adequate endplate preparation for interbody fusion can be achieved utilizing various minimally invasive approach techniques (mini-ALIF, MAS TLIF, MAS PLIF, XLIF), however, XLIF appears to provide a greater area of and more complete endplate preparation.
There are two modified TLIF, including MIS-TLIF and TLIF through Wiltse approach (W-TLIF). Although both of the two minimally invasive surgical procedures can be effective in the treatment for lumbar degenerative diseases, no comparative analysis has been made so far regarding their clinical outcomes.
Objective
To compare the clinical outcomes of MIS-TLIF and W-TLIF for the treatment for single-segment degenerative lumbar diseases.
Methods
Ninety-seven patients with single-segment degenerative lumbar disorders were included in this study. Forty-seven underwent MIS-TLIF surgery (group A). For group B, fifty patients underwent W-TLIF. The Japanese Orthopedic Association (JOA) score, the visual analog scale (VAS) of low back pain (LBP) and leg pain, MRI score and atrophy rate of CSA, interbody fusion rate were assessed during the postoperative follow-up.
Results
Incision length, blood loss, operative time, CPK, and postoperative incision pain VAS were better in group A (P < 0.05). The seconds of intraoperative fluoroscopy in groups A and B were 76 ± 9 and 7 ± 2, respectively (P < 0.05). In group B, The blood loss and CPK at L5-S1 were significantly higher than those at L4-5. Postoperative JOA scores, VAS of leg pain, and fusion rate were statistically the same between the two groups. VAS of LBP, MRI score, and atrophy rate of CSA was better in group A than in group B (P < 0.05).
Conclusion
Both methods are effective in the treatment for lumbar degenerative disease. MIS-TLIF has less blood loss, shorter surgical incision, and less lower postoperative back pain, while W-TLIF is less expensive for hospital stay with lower exposure to X-rays.
The most effective interbody fusion technique for degenerative disk disease (DDD) is still controversial. The purpose of our study is to compare pure lateral (LLIF) and oblique lateral (OLIF) approaches for the treatment of lumbar DDD from L1–L2 to L4–L5, in terms of clinical and radiological outcomes.
Materials and methods
45 patients underwent lumbar interbody fusion for pure lumbar DDD from L1–L2 to L4–L5 through LLIF (n?=?31, mean age 62.1 years, range 45–78 years) or OLIF (n?=?14, mean age 57.4 years, range 47–77 years). Clinical evaluations were performed with ODI and SF-36 tests. Radiological assessment was based on the modification of coronal segmental Cobb angles and segmental lumbar lordosis (L1–S1).
Results
On ODI and SF-36, all patients presented good results at follow-up, with 26% the difference between the LIF and OLIF groups on ODI scale in the post-operative period, and 3.9 and 8.8 points difference on physical and mental SF-36 in favor of OLIF. Radiological parameters improved significantly in both groups. The mean correction was 6.25° for cCobb (11.3° in LIF and 1.9° in OLIF), 2.5° for sLL (2° in LLIF and 4° in OLIF).
Conclusions
LLIF and OLIF represent safe and effective MIS procedures for the treatment of lumbar DDD. LLIF had some risks of motor deficit and monitoring is mandatory, though it addressed more the coronal deformities. OLIF did not imply risks for motor deficits, but attention should be paid to vascular anatomy. It was more effective in kyphotic segmental deformities.
Graphical abstract
These slides can be retrieved under Electronic Supplementary material.
Spondylodiscitis is a spinal infection affecting primarily the intervertebral disk and the adjacent vertebral bodies. Currently many aspects of the treatment of pyogenic spondylodiscitis are still a matter of debate.
Purpose
The aim of this study was to review the currently available literature systematically to determine the outcome of patients with pyogenic spondylodiscitis for conservative and surgical treatment strategies.
Methods
A systematic electronic search of MEDLINE, EMBASE, Cochrane Collaboration, and Web of Science regarding the treatment of pyogenic spondylodiscitis was performed. Included articles were assessed on risk of bias according the Cochrane Handbook for Systematic Reviews of Interventions, and the quality of evidence and strength of recommendation was evaluated according the GRADE approach.
Results
25 studies were included. Five studies had a high or moderate quality of evidence. One RCT suggest that 6 weeks of antibiotic treatment of pyogenic spondylodiscitis results in a similar outcome when compared to longer treatment duration. However, microorganism-specific studies suggest that at least 8 weeks of treatment is required for S. aureus and 8 weeks of Daptomycin for MRSA. The articles that described the outcome of surgical treatment strategies show that a large variety of surgical techniques can successfully treat spondylodiscitis. No additional long-term beneficial effect of surgical treatment could be shown in the studies comparing surgical versus antibiotic only treatment.
Conclusion
There is a strong level of recommendation for 6 weeks of antibiotic treatment in pyogenic spondylodiscitis although this has only been shown by one recent RCT. If surgical treatment is indicated, it has been suggested by two prospective studies with strong level of recommendation that an isolated anterior approach could result in a better clinical outcome.
The primary management of pyogenic spondylodiscitis is conservative. Once the causative organism has been identified, by blood culture or biopsy, administration of appropriate intravenous antibiotics is started. Occasionally patients do not respond to antibiotics and surgical irrigation and debridement is needed. The treatment of these cases is challenging and controversial. Furthermore, many affected patients have significant comorbidities often precluding more extensive surgical intervention. The aim of this study is to describe early results of a novel, minimally invasive percutaneous technique for disc irrigation and debridement in pyogenic spondylodiscitis.
Materials and methods
A series of 10 consecutive patients diagnosed with pyogenic spondylodiscitis received percutaneous disc irrigation and debridement. The procedure was performed by inserting two Jamshidi needles percutaneously into the disc space. Indications for surgery were poor response to antibiotic therapy (8 patients) and the need for more extensive biopsy (2 patients). Pre- and postoperative white blood cell count (WBC), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), Oswestry disability index (ODI), and visual analogue score (VAS) for back pain were collected. Minimum follow-up was 18 months, with regular interval assessments.
Results
There were 7 males and 3 females with a mean age of 67 years. The mean WBC before surgery was 14.63?×?109/L (10.9–26.4) and dropped to 7.48?×?109/L (5.6–9.8) after surgery. The mean preoperative CRP was 188 mg/L (111–250) and decreased to 13.83 mg/L (5–21) after surgery. Similar improvements were seen with ESR. All patients reported significant improvements in ODI and VAS scores after surgery. The average hospital stay after surgery was 8.17 days. All patients had resolution of the infection, and there were no complications associated with the procedure.
Conclusions
Our study confirms the feasibility and safety of our percutaneous technique for irrigation and debridement of pyogenic spondylodiscitis. Percutaneous irrigation and suction offers a truly minimally invasive option for managing recalcitrant spondylodiscitis or for diagnostic purposes. The approach used is very similar to discography and can be easily adapted to different hospital settings.
Minimally invasive surgical techniques have been developed to minimize tissue damage, reduce narcotic requirements, decrease blood loss, and, therefore, potentially avoid prolonged immobilization. Thus, the purpose of the present retrospective study was to assess the safety and efficacy of a minimally invasive posterior approach with transforaminal lumbar interbody debridement and fusion plus pedicle screw fixation in lumbar spondylodiscitis in comparison to an open surgical approach. Furthermore, treatment decisions based on the patient´s preoperative condition were analyzed.
Methods
67 patients with lumbar spondylodiscitis treated at our department were included in this retrospective analysis. The patients were categorized into two groups based on the surgical procedure: group (MIS) minimally invasive lumbar spinal fusion (n = 19); group (OPEN) open lumbar spinal fusion (n = 48). Evaluation included radiological parameters on magnetic resonance imaging (MRI), laboratory values, and clinical outcome.
Results
Preoperative MRI showed higher rates of paraspinal abscess (35.5 vs. 5.6%; p = 0.016) and multilocular location in the OPEN group (20 vs. 0%, p = 0.014). Overall pain at discharge was less in the MIS group: NRS 2.4 ± 1 vs. NRS 1.6 ± 1 (p = 0.036). The duration of hospital stay was longer in the OPEN than the MIS group (19.1 ± 12 days vs. 13.7 ± 5 days, p = 0.018).
Conclusion
The open technique is effective in all varieties of spondylodiscitis inclusive in epidural abscess formation. MIS can be applied safely and effectively as well in selected cases, even with epidural abscess.
The goal of this paper was to describe how endoscope-assisted oblique lumbar interbody fusion (OLIF) could remove huge lumbar disc herniation (HLDH) manifested with cauda equina syndrome (CES).
Methods
In this study, the authors made an attempt to treat CES with a direct endoscopic decompression through the OLIF corridor and performed OLIF in two patients with HLDH.
Results
Two patients with HLDH were successfully treated using OLIF with spinal endoscopic discectomy. We achieved direct ventral decompression by removal of herniated disc fragments located beyond the posterior longitudinal ligament (PLL). All preoperative symptoms in two patients improved postoperatively.
Conclusions
Endoscope-assisted oblique lumbar interbody fusion (OLIF) could successfully achieve neural decompression without additional posterior decompression in CES and could be used as an alternative treatment in well selected cases.
The aim of this study is to compare the clinical, radiological and functional outcome of anterior versus posterior surgical debridement and fixation in patients with thoracic and lumbar tuberculous spondylodiscitis.
Patients and methods
A total number of 42 patients with tuberculous spondylodiscitis of the thoracic and lumbar spine treated surgically were included in this study. Twenty patients (group A) underwent anterior debridement, decompression and instrumentation by anterior approach. Twenty-two patients (group B) were operated by posterolateral (extracavitary) decompression and posterior instrumentation. Operative parameters, clinical, radiographic and functional results for the two groups were analyzed and compared.
Results
The average follow-up period was 15 months (range 12–24) in both groups. The average operative time, blood loss and blood transfusion of anterior group were significantly less than the posterior one. There was significant better back pain relief, kyphotic angle correction and less angle loss in the posterior group than anterior. There was no significant difference between the two groups regarding neurological recovery, functional outcome and fusion rate.
Conclusion
Both anterolateral and posterolateral approaches are sufficient for achieving the goals of surgical treatment of thoracic and lumbar Pott’s disease but posterolateral approach allows significant better kyphotic angle correction, less angle loss, better improvement in back pain but unfortunately more operative time and blood loss.
Extreme lateral interbody fusion provides minimally invasive treatment of spinal deformity, but complications including nerve and psoas muscle injury have been noted. To avoid nerve injury, mini-open anterior retroperitoneal lumbar interbody fusion methods using an approach between the aorta and psoas, such as oblique lumbar interbody fusion (OLIF) have been applied. OLIF with percutaneous pedicle screws without posterior decompression can indirectly decompress the spinal canal in lumbar degenerated spondylolisthesis. In the current study, we examined the radiographic and clinical efficacy of OLIF for lumbar degenerated spondylolisthesis.
Methods
We assessed 20 patients with lumbar degenerated spondylolisthesis who underwent OLIF and percutaneous pedicle screw fixation without posterior laminectomy. MR and CT images and clinical symptoms were evaluated before and 6 months after surgery. Cross sections of the spinal canal were evaluated with MRI, and disk height, cross-sectional areas of intervertebral foramina, and degree of upper vertebral slip were evaluated with CT. Clinical symptoms including low back pain, leg pain, and lower extremity numbness were evaluated using a visual analog scale and the Oswestry Disability Index before and 6 months after surgery.
Results
After surgery, significant increases in axial and sagittal spinal canal diameter (12 and 32 %), spinal canal area (19 %), disk height (61 %), and intervertebral foramen areas (21 % on the right side, 39 % on the left), and significant decrease of upper vertebral slip (?9 %) were found (P < 0.05). Low back pain, leg pain, and lower extremity numbness were significantly reduced compared with before surgery (P < 0.05).
Conclusions
Significant improvements in disk height and spinal canal area were found after surgery. Bulging of disks was reduced through correction, and stretching the yellow ligament may have decompressed the spinal canal. Lumbar anterolateral fusion without laminectomy may be useful for lumbar spondylolisthesis with back and leg symptoms.
A prospective study to evaluate the results of monosegmental fixation; fixation of the fractured level with the adjacent vertebra sharing the same disc, in selected types of lumbar and thoracic fractures. This technique aims at saving motion levels by fusion of the only affected motion segment without sacrificing other levels.
Methods
Forty patients enrolled in this study between August 2011 and October 2013. The inclusion criteria were recent thoracic or lumbar vertebral fractures (less than 2 weeks). The fracture involves only one of the end plates of the vertebrae (either the superior or the inferior). The other end plate and both pedicles should be intact. The exclusion criteria were cervical fractures, fractures that include both end plates or pedicles of the vertebra, fracture dislocation, and load sharing classification score more than seven. All patients underwent monosegmental fixation with pedicle screw fixation. Eight patients were supplemented with interbody grafts. Radiological evaluation was done to assess local kyphosis angle, degree of compression of the anterior column, the degree of comminution, retropulsed fragment, neural canal compromise, integrity of the affected end plate, exclusion of pedicle fracture, and most important to assure that only one end plate is affected. All patients were assessed neurologically according to Frankel grading system. Patient were assessed by Denis pain scale and Denis work scale.
Results
The age of the patients was of a mean of 34.5 years old. All patients were Frankle E at time of presentation and remained the same post-operative. The mean operative time from incision time to end of skin closure was 74.2 min. The mean blood loss was 230 ml. The pre-operative degree of local kyphosis; was of a mean 8.22°. This was improved to 2.25° at the immediate postoperative x-rays. At two years follow up, the loss of correction was of a mean 0.85° which was insignificant. The pre-operative percentage of height lost improved from a mean of 56.05 % to post-operative mean of 90.125 %. At the end of follow up, no pseudoarthrosis cases or metal failure were noticed.
Discussion
Thoracic and lumbar fractures are common in young adults. Surgical treatment offers early rehabilitation and preserves spine alignment. Monosegmental fixation technique in selected types of dorsal and lumbar fractures offers spine stability and preserves motion segments. It fuses only one motion segment that is prone for later instability or deformity. Reconstrcution of the anterior column can be achieved through TLIF approach in combination of monosegmental fixation to achieve 360° fusion.
Conclusion
Monosegmental fixation is an effective technique. It can save motion segments in young patients with adequate spine stability and good functional outcomes.
Restoring sagittal alignment is an important factor in the treatment of spinal deformities. Recent investigations have determined that releasing the anterior longitudinal ligament (ALL) and placing hyperlordotic cages can increase lordosis, while minimizing need for 3 column osteotomies. The influences of parameters such as cage height and angle have not been determined. Finite element analysis was employed to assess the extent of lordosis achievable after placement of different sized lordotic cages.
Methods
A 3-dimensional model of a L3–4 segment was used. Disc distraction was simulated by inserting interbody cages mid-body in the disc space. Analyses were performed in the following conditions: (1) intact, (2) ALL release, (3) ALL release + facetectomy, and (4) ALL release + posterior column osteotomy. Changes in segmental lordosis, disc height, foraminal height, and foraminal area were measured.
Results
After ALL resection and insertion of hyperlordotic cages, lordosis was increased in all cases. The lordosis achieved by the shorter cages was less due to posterior disc height maintained by the facet joints. A facetectomy increased segmental lordosis, but led to contact between the spinous processes. For some configurations, a posterior column osteotomy was required if the end goal was to match cage angle to intradiscal angle.
Conclusion
Increased segmental lumbar lordosis is achievable with hyperlordotic cages after ALL resection. Increased cage height tended to increase the amount of lordosis achieved, although in some cases additional posterior bone resection was required to maximize lordosis. Further studies are needed to evaluate the impact on regional lumbar lordosis.
Sagittal imbalance is a spine deformity with multifactorial etiology, associated with severe low back pain and gait disturbance that worsen deeply patients’ quality of life. The amount of correction achievable through PSO is limited by the height of the resection of the posterior wall, causing a ceiling of segmental correction of 30–35°. The aim of this study is to describe and preliminarily evaluate the results of an alternative technique, corner osteotomy (CO), that can increase the amount of correction.
Materials and methods
From March 2012, every patient examined in our Division, diagnosed with sagittal imbalance to be treated with PSO, underwent CO and fusion. This technique consists in removing the posterior vertebral arch, the pedicle and the posterior–superior corner of the vertebral body; the inferior endplate of the vertebra above is prepared and the superior adjacent disc removed to obtain, when closing the osteotomy, a direct interbody fusion. Ten patients undergoing CO were compared with 20 patients undergoing PSO regarding spinopelvic parameters, operative variables, complications and degree of correction.
Results
Patients undergoing CO obtained higher lordotic angle at the osteotomy than patients undergoing PSO (36.6° ± 8.2° vs 16.5° ± 9.5°, p < 0.001) and had lower postoperative PT and SVA and higher average increase in lordosis. Complications were similar between groups. A trend toward longer surgical time, greater bleeding and higher transfusion rate was observed in the CO group, though this finding could be related to higher complexity of cases or incidence of associated anterior approach.
Discussion and conclusions
Corner osteotomy technique was more effective than the PSO in increasing segmental and lumbar lordosis with modest increase in blood loss and similar complication rate. The CO technique, in addition, proved a good reproducibility. Further studies with larger populations should confirm these preliminary results.
This study aimed to evaluate if closed suction wound drainage is necessary in minimally invasive surgery of transforaminal lumbar interbody fusion (MIS TLIF).
Methods
This is a prospective randomized clinical study. Fifty-six patients who underwent MIS TLIF were randomly divided into groups A (with a closed suction wound drainage) and B (without tube drainage). Surgical duration, intraoperative blood loss, timing of ambulation, length of hospital stay and complications were recorded. Patients were followed up for an average of 25.3 months. Clinical outcome was assessed using the Oswestry disability index and visual analogue scale (VAS). Fusion rate was classified with the Bridwell grading system, based on plain radiograph.
Results
Both groups had similar patient demographics. The use of drains had no significant influence on perioperative parameters including operative time, estimated blood loss, length of stay and complications. Patients in group B started ambulation 1 day earlier than patients in group A (p < 0.001). Clinical outcomes were comparable between group A and group B.
Conclusion
A drain tube can lead to pain, anxiety and discomfort during the postoperative period. We conclude that drain tubes are not necessary for MIS TLIF. Patients without drains had the benefit of earlier ambulation than those with drains.
