Can Unilateral Minimally Invasive Transforaminal Lumbar Interbody Fusion (MIS TLIF) Result in Sufficient Reduction in Spondylolisthesis?: A Comparison with Open TLIF and Bilateral MIS TLIF

STUDY DESIGN: Retrospective study. OBJECTIVES: To compare the radiologic results of unilateral or bilateral minimal invasive transforaminal lumbar interbody fusion (MIS TLIF) and conventional open lumbar interbody fusion. SUMMARY OF LITERATURE REVIEW: Only a few studies have compared the slip reduction and fusion rate between unilateral or bilateral MIS TLIF and conventional open TLIF. MATERIALS AND METHODS: Between March 2007 and May 2015, 80 patients with single-level low-grade spondylolisthesis underwent unilateral MIS TLIF (26 patients), bilateral MIS TLIF (10 patients), or open TLIF (44 patients) by a single surgeon. Radiologic studies were performed preoperatively, 2 weeks postoperatively, and 12 months postoperatively. Slip reduction, the lumbar lordortic angle, and the fusion rate were analyzed. RESULTS: The 3 groups exhibited significantly improved slip after operation. Significant differences were found among the 3 groups (p=0.015) and between the MIS TLIF group (31.76%±14.42%) and the open TLIF group (41.66%±15.98%) (p=0.01) in the slip reduction rate at 2 weeks after the operation. However, no significant difference was found between unilateral MIS TLIF and bilateral MIS TLIF (37.61%±15.0% vs. 29.5%±13.82%, p=0.148). In the lumbar lordotic angle, no significant difference was found among the 3 groups. There were no significant differences among the 3 groups in slip reduction or the fusion rate at 12 months after the operation. CONCLUSIONS: Our study suggests that unilateral MIS TLIF showed a similar slip reduction and fusion rate to bilateral MIS TLIF, but that conventional open TLIF showed better slip reduction than MIS TLIF, although it had a similar fusion rate.

Surgical Strategies for Successful Minimally Invasive Transforaminal Lumbar Interbody Fusion

STUDY DESIGN: Literature review. OBJECTIVES: The aim of this study was to demonstrate surgical strategies for successful minimally invasive transforaminal lumbar interbody fusion (TLIF). SUMMARY OF LITERATURE REVIEW: Although many studies have reported the benefits and disadvantages of minimally invasive TLIF, few have described surgical strategies to improve the success rate or to reduce complications. MATERIALS AND METHODS: We searched for studies reporting the clinical and radiological outcomes of minimally invasive TLIF, and analyzed the optimal indications, technical pitfalls, and tips for successful surgical outcomes. RESULTS: The ideal candidate for minimally invasive TLIF is a patient with single or 2-level low-grade adult degenerative or isthmic spondylolisthesis. Incomplete decompression, dura tearing, nerve root injury, and implant-related complications were found to be the most commonly reported adverse events, especially in the early periods of a surgeon's experience. Precise positioning for skin incision and tube insertion, complete neural decompression, proper interbody preparation for bone graft and cage insertion, and the correct placement of percutaneous pedicle screws are critical strategies for successful surgical outcomes. Fully understanding the surgical pitfalls and tips described in this review is also important to avoid potential complications. CONCLUSIONS: It is imperative not only to carry out a comprehensive preoperative evaluation and proper patient selection, but also to perform meticulous surgical procedures with thoughtful considerations of potential pitfalls, in order to improve the success rate and to reduce the complications of minimally invasive TLIF.

Comparison of Clinical and Physiological Efficacies of Different Intermittent Sequential Pneumatic Compression Devices in Preventing Deep Vein Thrombosis: A Prospective Randomized Study

BACKGROUND: There are few comparative studies about the optimal method of pneumatic compression to prevent deep vein thrombosis (DVT). The aim of this prospective randomized study was to compare venous hemodynamic changes and their clinical influences between two graded sequential compression groups (an alternate sequential compression device [ASCD] vs. a simultaneous sequential compression device [SSCD]). METHODS: In total, 34 patients (68 limbs) undergoing knee and spine operations were prospectively randomized into two device groups (ASCD vs. SSCD groups). Duplex ultrasonography examinations were performed on the 4th and 7th postoperative days for the detection of DVT and the evaluation of venous hemodynamics. Continuous data for the two groups were analyzed using a two-tailed, unpaired t-test. Relative frequencies of unpaired samples were compared using Fisher exact test. Mixed effects models that might be viewed as ANCOVA models were also considered. RESULTS: DVT developed in 7 patients (20.6%), all of whom were asymptomatic for isolated calf DVTs. Two of these patients were from the ASCD group (11.8%) and the other five were from the SSCD group (29.4%), but there was no significant difference (p = 0.331). Baseline peak velocity, mean velocity, peak volume flow, and total volume flow were enhanced significantly in both device groups (p < 0.001). However, the degrees of flow and velocity enhancement did not differ significantly between the groups. The accumulated expelled volumes for an hour were in favor of the ASCD group. CONCLUSIONS: Both graded sequential compression devices showed similar results both in clinical and physiological efficacies. Further studies are required to investigate the optimal intermittent pneumatic compression method for enhanced hemodynamic efficacy and better thromboprophylaxis.

Two Cases of Invasive Infections Caused by Arcanobacterium haemolyticum in Immunocompetent Adult / 감염과화학요법

Arcanobacterium haemolyticum is a gram-positive bacillus that is most commonly implicated in pharyngitis and infections of the skin and soft tissue. Systemic and deep-seated infections caused by this organism are rarely reported in the literature. Recently, we encountered two cases of invasive infections caused by A. haemolyticum. We describe two cases, one with vertebral osteomyelitis with an epidural abscess and the other with a buttock abscess with bacteremia.

The Usefulness of Bone Turnover Marker as a Predictive Factor In Osteopenic Postmenopausal Women / 대한정형외과연구학회지

PURPOSE: To assess the relationship between biochemical bone turnover marker and bone mineral density(BMD) and to evaluate the predictive role of biochemical bone marker in postmenopausal osteopenic woman. MATERIALS AND METHODS: Ninety two postmenopausal women (50-65 years old), who have the T-score from -1.0 to -2.5 by the dual-energy X-ray absorptiometry (DEXA), were examined consecutively with BMD of the lumbar spine and biochemical bone turnover marker including urine Cross-linked N-telopeptide of type I collagen (u-NTX), urine deoxy-pyridinoline (u-DPD), serum Cross-linked C-telopeptide of type I collagen (s-CTX), serum bone-specific alkaline phosphatase (s-BAP), serum osteocalcin (s-OC) for six months. We evaluated the relation between the changes in the biochemical markers and the rate of bone loss. RESULTS: Seventy four postmenopausal women completed this study. All biochemical bone turnover marker and BMD at one time point including the baseline and the end point did not show any significant correlation. Another longitudinal study found no significant correlation between the baseline biochemical bone turnover marker and the change in lumbar spine BMD. The other study showed significant correlation between the changes in s-CTX/s-OC and the change in lumbar spine BMD (p=0.04, 0.03). The changes of u-NTX and s-OC were larger in the group of aggravation in BMD (p=0.032, 0.041). CONCLUSION: The relationship between bone turnover marker and BMD at one time point was not clear. The predictive role of baseline bone turnover marker was limited to predict the magnitude of changes in lumbar BMD in untreated osteopenic individuals. The changes of s-OC showed significant predictive role in the bone loss in osteopenic postmenopausal women.

Differential Diagnosis between Tuberculous Spondylitis and Pyogenic Spondylitis / 대한척추외과학회지

STUDY DESIGN: This is a retrospective study OBJECTIVES: We wanted to make the early differential diagnosis between tuberculous spondylitis and pyogenic spondylitis according to the clinical and MRI findings. SUMMARY OF THE LITERATURE REVIEW: Making an early differential diagnosis between tuberculous spondylitis and pyogenic spondylitis is essential to start prompt and proper treatment. However, the clinical symptoms and MRI findings of both these illnesses can vary considerably. MATERIAL AND METHOD: Ninety-five patients (49 men and 46 women, mean age: 54.5) who were treated from January 2001 to February 2007 and whose diagnosis was confirmed by laboratory or pathological studies were retrospectively reviewed. 50 patients with tuberculous spondylitis and 45 patients with primary pyogenic spondylitis were included. The patients with combined infection or an uncertain diagnosis were excluded. We compared the medical records and MRI findings between the different groups of patients. RESULTS: The patients with tuberculous spondylitis were younger (48.2 years vs. 61.5 years, respectively) and they had a longer symptom duration (4.3 months vs 1.8 months, respectively). The erythrocyte sedimentation rate (ESR) and the C-reactive protein (CRP) level were significantly higher in the patients with pyogenic spondylitis (71.3/49.6 mm/hr and5.74/2.98 mg/dl, respectively). A high fever above 38 degree was more frequent in the patients with pyogenic spondylitis. Intraosseous abscess, epidural abscess, a well-definded paraspinal abscess, focal enhancement and severe destruction of the vertebral body on MRI were more frequent in the patients with tuberculous spondylitis. Four parameters such as a symptom duration longer than 3 months, no fever higher than 38 degree, a well-defined paravertebral abscess and an intraosseous abscess were selected. 42 patients in the tuberculous group had 3 or more of these four parameters. The sensitivity and specificity of these combined 4 parameters were 84% and 97.8%, respectively, for making the differential diagnosis between these 2 maladies. CONCLUSION: These diagnostic criteria might be useful to discriminate between tuberculous spondylitis and pyogenic spondylitis even without definite laboratory or pathological results.

A Comparative Experimental Study of Allograft andPorous Hydroxyapatite as Bone Substitutes / 대한정형외과학회잡지

PURPOSE: An experimental animal study was performed to compare the bone fusion capacity of an allograft and porous hydroxyapatite. MATERIALS AND METHODS: Three milliliters of allograft or porous hydroxyapatite particles were inserted between the 4th and 5th lumbar transverse processes of New Zealand white rabbits weighing 3-3.5 kg. The total number of rabbits was 30, which were divided randomly into 2 groups. The bone formation and fusion capacity were evaluated 12 weeks after surgery through the gross findings and manual palpation, as well as radiological, biomechanical, and histological studies. Six rabbits in the allograft group died during breeding but the autopsy finding did not show any evidence suggesting an infection or graft rejection. The allograft was harvested from the iliac crest of the rabbits of the same species aseptically and was preserved at ??80oC for at least 7 days before implantation. RESULTS: The fusion rates were 55.6% (5/9) and 66.7% (10/15) in the allograft and porous hydroxyapatite groups, respectively. The mean values of the tensile strengths were 140.7 N in the allograft group and 189.6 N in the porous hydroxyapatite group. Histological analysis of 2 specimens from each group revealed theporous hydroxyapatite group to show a slightly better osteoconduction capacity. CONCLUSION: The porous hydroxyapatite group showed better bony union capacity even though there was no significant difference between the 2 groups.

The Classification of Idiopathic Scoliosis / 대한척추외과학회지

There are many classifications for idiopathic scoliosis but none of these is perfect. In the treatment of idiopathic scoliosis, it is essential to understand the characteristics of each classification system and exploit their individual advantages.

The Kyphotic Deformity After Multi-level Laminectomy / 대한척추외과학회지

STUDY DESIGN: A Retrospective study OBJECTIVES: To analyze the characteristics, risk factors, and outcomes of postlaminectomy kyphosis. SUMMARY OF LITERATURE REVIEW: Postlaminectomy kyphosis is uncommon and poorly understood, with controversy over the cause, risk factors, and treatment. MATERIAL AND METHODS: We included 17 patients (8 male, 9 female) who had undergone multilevel laminectomy between 1982 to 2006. Their mean age at the time of laminectomy was 16.3 years. The locations of laminectomy were: 4 cervical/cervicothoracic, 10 thoracic/thoracolumbar, and 3 lumbar. Possible factors for developing kyphotic deformities, such as an age at the time of laminectomy, sex, location, laminectomy extent, and radiation therapy were analyzed with the deformity angle and the time interval from the operation to the occurrence of deformity. RESULTS: The mean time after surgery was 18.3 months, and the mean kyphotic angle was 58 degrees. Patients younger than 12 years or surgery involving more than 4 segments had a slightly shorter time interval, but not significantly. Location had no significant correlation with angle and time interval. Radiation therapy and sex were not significant factors. Most (15) patients received corrective surgery 49.9 months after laminectomy, which reduced deformities to an average of 34.5 degrees, whereas 2 patients had mild curvatures of 38 degrees (mean) One patient received a second operation due to pull-out of a rod, and one patient had a postoperative infection. CONCLUSION: Postlaminectomy kyphosis attends to occur earlier in younger patients and patients with a large number of laminas resected, so careful observation should be done for early detection and management.

Clinical and Radiological Results of Revision Acetabular Arthroplasty using an Acetabular Roof Reinforcement Ring / 대한정형외과학회잡지

PURPOSE: We evaluated the clinical and radiological results of acetabular reconstructions using an acetabular roof reinforcement ring (ARR). MATERIALS AND METHODS: From May 1993 to November 1999, 18 hips revised with ARR were evaluated. The mean age at operation was 53 years. The average follow-up period was 51 months (24-94 months). Acetabular defects were classified based on the AAOS classification system. There was one case of type IIA defect, six cases of type IIB defect, ten cases of type III defect and one case of type IV defect. All were treated with morselized allografts and autografts, and three were reconstructed with additional structural autografts. RESULTS: The average Harris hip score improved from 54 preoperatively to 76 postoperatively, but five patients complained of intermittent hip pain. On the last follow-up radiographs, the bone grafts were united and remodeled in all cases, but only partial resorption was observed in two hips. We found evidence of osteolysis in four hips and observed cup migration in three hips. Three hips, in which Muller rings were used, were re-revised during the follow-up period. CONCLUSION: Acetabular reconstruction using ARR led to good clinical and radiological results, but a relative high rate of rerevision was shown in the cases fitted with the Muller ring. Appropriate ARR should be used depending on the extent of the acetabular defect.