Factors prolonging antibiotic duration and impact of early surgery in thoracolumbar pyogenic spondylitis treated with minimally invasive posterior fixation.

PURPOSE: A standard 6-12-week course of antibiotics is recommended for pyogenic spondylitis. Recent evidence supports early minimally invasive posterior fixation surgery; however, its effect on antibiotic treatment duration is unclear. This study aims to identify factors associated with prolonged antibiotic treatment in thoracolumbar pyogenic spondylitis patients resistant to conservative treatment and assess whether early surgery can reduce treatment duration. METHODS: We retrospectively reviewed 74 patients with thoracolumbar pyogenic spondylitis undergoing minimally invasive posterior fixation at nine facilities. Patients were grouped based on antibiotic duration (≥ 6 or < 6 weeks) and timing of surgery (≤ 3 weeks or > 3 weeks of starting antibiotics). Univariable and multivariable logistic regression analyses were used to identify factors associated with prolonged antibiotic treatment and study the outcomes of patients undergoing early surgery. RESULTS: Forty-nine patients (66%) required prolonged antibiotic treatment. The presence of an iliopsoas abscess (p = 0.0006) and elevated C-reactive protein (CRP) levels (≥ 10 mg/dL, p = 0.015) were independently associated with prolonged antibiotic treatment. Early surgery significantly reduced total antibiotic duration (5.3 weeks vs. 9.9 weeks, p < 0.0001) without increasing the incidence of postoperative infection recurrences and unplanned additional surgeries. Despite factors associated with prolonged antibiotic treatment, early surgery consistently shortened the treatment duration compared to late surgery. CONCLUSIONS: Early surgery (within three weeks) with minimally invasive posterior fixation for thoracolumbar pyogenic spondylitis is associated with reduced antibiotic duration and overall treatment duration regardless of the presence of prolonging factors like iliopsoas abscess and elevated CRP levels.

Unique characteristics of bone union at the infected vertebrae after minimally invasive posterior fixation without bone grafting in thoracolumbar pyogenic spondylitis: a retrospective multicenter cohort study.

BACKGROUND: The current study aimed to evaluate the bone union rate between infected vertebrae after minimally invasive posterior fixation without bone grafting in thoracolumbar pyogenic spondylitis. METHODS: This retrospective multicenter cohort study evaluated 75 patients of posterior fixation for thoracolumbar pyogenic spondylitis that have been recorded at six relevant institutions from January 2016 to December 2022. Data on age, sex, location of infected vertebrae, number of infected disks, comorbidity, Pola classification, number of vertebrae fixed according to surgery, implant failure requiring revision surgery, and distance according to the type of infected vertebrae after surgery were evaluated. Further, their association with postoperative bone union was investigated > 12 months postoperatively. RESULTS: Finally, 40 patients were included in the study. In total, 32 (80%) patients achieved bone union at the infected vertebrae after minimally invasive posterior fixation without bone grafting. The mean duration from surgery to union was 10.7 months. Twenty-six (65%) patients initially achieved bone union at the lateral and/or anterior bridging callus. Patients with multiple-level infected disks (33%, 2/6 patients) had a lower bone union rate than those with a single-level infected disk (88%, 30/34 patients) (p = 0.0095). CONCLUSIONS: In 80% of patients, bone union at the infected vertebrae was achieved after minimally invasive posterior fixation without bone grafting in thoracolumbar pyogenic spondylitis. A total of 65% of the patients achieved initial bone union at the lateral and/or anterior bridging callus. Moreover, patients with multiple-level infected disks had a low bone union rate. Hence, the treatment strategy should be cautiously considered. TRIAL REGISTRATION: This study was registered retrospectively and all procedures used in this study including the review of patient records were approved by the institutional review board.

Impact of causative organism identification on clinical outcomes after minimally invasive posterior fixation for thoracolumbar pyogenic spondylitis: multicenter retrospective cohort study.

PURPOSE: This study aimed to evaluate the difference in treatment duration and unplanned additional surgeries between patients with unidentified causative organisms on empiric antibiotics and those with identified organisms on selective antibiotics in treating thoracolumbar pyogenic spondylitis with minimally invasive posterior fixation. METHODS: This multicenter retrospective cohort study included patients with thoracolumbar pyogenic spondylitis refractory to conservative treatment who underwent minimally invasive posterior fixation. Patients were divided into the identified (known causative organism) and unidentified groups (unknown causative organism). We analyzed data on demographics, antibiotic use, surgical outcomes, and infection control indicators. RESULTS: We included 74 patients, with 52 (70%) and 22 (30%) in the identified and unidentified groups, respectively. On admission, the identified group had higher C-reactive protein (CRP) levels and more iliopsoas abscesses. The duration to postoperative CRP negative was similar in the identified and unidentified groups (7.13 vs. 6.48 weeks, p = 0.74). Only the identified group had unplanned additional surgeries due to poor infection control, affecting 6 of 52 patients (12%). Advanced age and causative organism identification increased the additional surgery odds (odds ratio [OR], 8.25; p = 0.033 and OR, 6.83; p = 0.034, respectively). CONCLUSION: The use of empiric antibiotics in minimally invasive posterior fixation was effective without identifying the causative organism and did not prolong treatment duration. In patients with identified organisms, 12% required unplanned additional surgery, indicating a more challenging infection control. Causative organism identification was associated with the need for additional surgery, suggesting a more cautious treatment strategy for these patients.

Pedicle screw insertion into infected vertebrae reduces operative time and range of fixation in minimally invasive posterior fixation for thoracolumbar pyogenic spondylitis: a multicenter retrospective cohort study.

BACKGROUND: Minimally invasive posterior fixation surgery for pyogenic spondylitis is known to reduce invasiveness and complication rates; however, the outcomes of concomitant insertion of pedicle screws (PS) into the infected vertebrae via the posterior approach are undetermined. This study aimed to assess the safety and efficacy of PS insertion into infected vertebrae in minimally invasive posterior fixation for thoracolumbar pyogenic spondylitis. METHODS: This multicenter retrospective cohort study included 70 patients undergoing minimally invasive posterior fixation for thoracolumbar pyogenic spondylitis across nine institutions. Patients were categorized into insertion and skip groups based on PS insertion into infected vertebrae, and surgical data and postoperative outcomes, particularly unplanned reoperations due to complications, were compared. RESULTS: The mean age of the 70 patients was 72.8 years. The insertion group (n = 36) had shorter operative times (146 versus 195 min, p = 0.032) and a reduced range of fixation (5.4 versus 6.9 vertebrae, p = 0.0009) compared to the skip group (n = 34). Unplanned reoperations occurred in 24% (n = 17) due to surgical site infections (SSI) or implant failure; the incidence was comparable between the groups. Poor infection control necessitating additional anterior surgery was reported in four patients in the skip group. CONCLUSIONS: PS insertion into infected vertebrae during minimally invasive posterior fixation reduces the operative time and range of fixation without increasing the occurrence of unplanned reoperations due to SSI or implant failure. Judicious PS insertion in patients with minimal bone destruction in thoracolumbar pyogenic spondylitis can minimize surgical invasiveness.

Treatment of Thoracolumbar Pyogenic Spondylitis with Minimally Invasive Posterior Fixation without Anterior Lesion Debridement or Bone Grafting: A Multicenter Case Study.

The usefulness of minimally invasive posterior fixation without debridement and autogenous bone grafting remains unknown. This multicenter case series aimed to determine the clinical outcomes and limitations of this method for thoracolumbar pyogenic spondylitis. Patients with thoracolumbar pyogenic spondylitis treated with minimally invasive posterior fixation alone were retrospectively evaluated at nine affiliated hospitals since April 2016. The study included 31 patients (23 men and 8 women; mean age, 73.3 years). The clinical course of the patients and requirement of additional anterior surgery constituted the study outcomes. The postoperative numerical rating scale score for lower back pain was significantly smaller than the preoperative score (5.8 vs. 3.6, p = 0.0055). The preoperative local kyphosis angle was 6.7°, which was corrected to 0.1° after surgery and 3.7° at the final follow-up visit. Owing to failed infection control, three patients (9.6%) required additional anterior debridement and autogenous bone grafting. Thus, in this multicenter case series, a large proportion of patients with thoracolumbar pyogenic spondylitis could be treated with minimally invasive posterior fixation alone, thereby indicating it as a treatment option for pyogenic spondylitis.

Charcot spinal arthropathy presenting as adjacent segment disease after lumbar spinal fusion surgery in Parkinson's disease: A case report.

Charcot spinal arthropathy (CSA) is a rare spinal disorder presenting neuropathic osteoarthropathy of facet joints leading to progressive destruction. After L4-5 PLIF, a 63-year-old woman with Parkinson's disease (PD) underwent L3-4 and L5-S1 PLIF for primary adjacent segment disease caused by degenerative change, which was found as facet joint osteophytes and a vacuum disc phenomenon with endplate sclerosis. However, her postural disorder from PD deteriorated, and strong opioid analgesics were administered for severe recurring low back pain. Anterior subluxation at L2-3 occurred because of destructive secondary adjacent segment disease, which was found as destruction of the endplate and the facet without degenerative change, and formation of paravertebral osteophytes and fluid collection in the intervertebral space. The appearance on imaging met that for neuroarthropathic change, which was previously reported as CSA. L2-3 PLIF following extension of posterior fusion to T10 was additionally performed, and the postoperative course was uneventful with symptomatic improvement. In this case, the important finding was in the different appearance of the disease between adjacent segments on imaging. It is possible that deterioration of PD and administration of the analgesics inhibited deep pain sensation, and concentration of mechanical stress in the proximal adjacent segment by the long lever arm because of extension of the fusion level resulted in neuroarthropathic change of the facets in the secondary adjacent segments. The pathophysiology of association of CSA and PD remains unknown. However, we recommend vigilance for destructive neuroarthropathic facet change as CSA after spinal surgery in patients with severe PD.

Analysis of muscle activity during active pelvic tilting in sagittal plane.

BACKGROUND: Pelvic tilting is performed to improve lumbopelvic flexibility or retrain the motor control of local muscles. However, few studies investigated the activity of local muscles during pelvic tilting. PURPOSE: The purpose of this study was to investigate muscle activity during anterior and posterior pelvic tilting. METHOD: Twelve healthy males (age, 22.6 ± 1.4 years) participated. Fine-wire electrodes were inserted into the bilateral lumbar multifidus (MF) and transversus abdominis (TrA). Surface electrodes were used to record activity of the bilateral rectus abdominis, external oblique, and erector spinae (ES), and the unilateral right latissimus dorsi, gluteus maximus, semitendinosus, and rectus femoris muscles. The electromyographic activities during anterior and posterior pelvic tilting in a standing position were recorded and expressed as a percentage of the maximum voluntary contraction (%MVC) for each muscle. RESULTS: The activities of the bilateral MF (right: 23.9 ± 15.9 %MVC, left: 23.9 ± 15.1 %MVC) and right ES (19.0 ± 13.3 %MVC) were significantly greater than those of the other muscles during anterior pelvic tilting. The activity of the left TrA (14.8 ± 16.4 %MVC) was significantly greater than that of the other muscles during posterior pelvic tilting. CONCLUSIONS: The results suggested that the MF and ES are related to anterior pelvic tilting. The activity of the TrA, which was classified as a local muscle, was greater during posterior pelvic tilting. This study indicated that local muscles such as the MF and TrA may be related to pelvic tilting.

Abdominal muscle activity during a standing long jump.

STUDY DESIGN: Experimental laboratory study. OBJECTIVES: To measure the activation patterns (onset and magnitude) of the abdominal muscles during a standing long jump using wire and surface electromyography. BACKGROUND: Activation patterns of the abdominal muscles, especially the deep muscles such as the transversus abdominis (TrA), have yet to be examined during full-body movements such as jumping. METHODS: Thirteen healthy men participated. Wire electrodes were inserted into the TrA with the guidance of ultrasonography, and surface electrodes were attached to the skin overlying the rectus abdominis (RA) and external oblique (EO). Electromyographic signals and video images were recorded while each subject performed a standing long jump. The jump task was divided into 3 phases: preparation, push-off, and float. For each muscle, activation onset relative to the onset of the RA and normalized muscle activation levels (percent maximum voluntary contraction) were analyzed during each phase. Comparisons between muscles and phases were assessed using 2-way analyses of variance. RESULTS: The onset times of the TrA and EO relative to the onset of the RA were -0.13 ? 0.17 seconds and -0.02 ? 0.07 seconds, respectively. Onset of TrA activation was earlier than that of the EO. The activation levels of all 3 muscles were significantly greater during the push-off phase than during the preparation and float phases. CONCLUSION: Consistent with previously published trunk-perturbation studies in healthy persons, the TrA was activated prior to the RA and EO. Additionally, the highest muscle activation levels were observed during the push-off phase.

Trunk muscle activity while lifting objects of unexpected weight.

OBJECTIVE: To determine trunk muscle activity when lifting an object of greater weight than expected, which may contribute to the development of low back pain. DESIGN: Electromyographic evaluation of trunk muscle activity. SETTING: University of Tsukuba, Spine laboratory. PARTICIPANTS: Eleven healthy men with a mean age of 24 (SD 2) years. INTERVENTIONS: Trunk muscle activity was measured when subjects lifted an object with their right arm in immediate response to a light stimulus. Surface and wire electrodes were used to measure the activity of the rectus abdominis, external oblique and erector spinae muscles, and the transversus abdominis and lumbar multifidus muscles, respectively. The lifting tests were performed in three different settings: lifting an expected 1-kg object, lifting an unexpected 4-kg object (erroneously expected to weigh 1 kg), and lifting an expected 4-kg object. MAIN OUTCOME MEASURES: The muscle activity induced when subjects lifted objects of different weights was compared by calculating the root mean square (RMS) of muscle activity at rest and % maximum voluntary contraction. RESULTS: When the subjects were aware of the weight of the object to be lifted, the activity of the external oblique, transversus abdominis, erector spinae and lumbar multifidus muscles increased immediately after lifting. When the subjects were not aware of the weight of the object to be lifted, the increase in muscle activity was delayed (P<0.05). CONCLUSIONS: Trunk muscles may not be able to function appropriately when individuals lift an object that is much heavier than expected.

Electromyographic analysis of transversus abdominis and lumbar multifidus using wire electrodes during lumbar stabilization exercises.

STUDY DESIGN: Experimental laboratory study. OBJECTIVES: To measure trunk muscle activity using wire electrodes during lumbar stabilization exercises and to examine if more effective exercises to activate the deep trunk muscles (local muscles) exist. BACKGROUND: Lumbar stabilization exercises are performed to improve motor control of trunk muscles. However, the magnitude of activation of local muscles during lumbar stabilization exercises is not clear. METHODS: Nine healthy men with no history of lumbar spine disorders participated in the study. Fine-wire electrodes were inserted into the transversus abdominis (TrA) and lumbar multifidus, bilaterally. In addition, surface electrodes were attached to the rectus abdominis, external obliques, and erector spinae, bilaterally. Electromyographic signal amplitude was measured during the following exercises: elbow-toe, hand-knee, back bridge, side bridge, and curl-up. Two-way analyses of variance were used to compare muscle activity level among exercises and between sides for each muscle. RESULTS: The exercise showing the greatest activity level for the TrA was elbow-toe exercise with contralateral arm and leg lift. In addition, for the TrA, a significant side-to-side difference in activation level was demonstrated for 7 of the 11 exercises that were performed. The activity level of the multifidus was greatest during the back bridge exercises. The curl-up exercise generated the highest activity level for the rectus abdominis and the back bridge, with single-leg lift exercises generating the highest erector spinae activity. CONCLUSIONS: The exercises investigated in this study resulted in a wide range of effort level for all 5 muscles monitored. Many of the exercises also resulted in an asymmetrical (right versus left side) activation level for a muscle, including the TrA.

Trunk muscle activity during lumbar stabilization exercises on both a stable and unstable surface.

STUDY DESIGN: Controlled laboratory study. OBJECTIVES: To clarify whether differences in surface stability influence trunk muscle activity. BACKGROUND: Lumbar stabilization exercises on unstable surfaces are performed widely. One perceived advantage in performing stabilization exercises on unstable surfaces is the potential for increased muscular demand. However, there is little evidence in the literature to help establish whether this assumption is correct. METHODS: Nine healthy male subjects performed lumbar stabilization exercises. Pairs of intramuscular fine-wire or surface electrodes were used to record the electromyographic signal amplitude of the rectus abdominis, the external obliques, the transversus abdominis, the erector spinae, and lumbar multifidus. Five exercises were performed on the floor and on an unstable surface: elbow-toe, hand-knee, curl-up, side bridge, and back bridge. The EMG data were normalized as the percentage of the maximum voluntary contraction, and data between doing each exercise on the stable versus unstable surface were compared using a Wilcoxon signed-rank test. RESULTS: With the elbow-toe exercise, the activity level for all muscles was enhanced when performed on the unstable surface. When performing the hand-knee and side bridge exercises, activity level of the more global muscles was enhanced when performed on an unstable surface. Performing the curl-up exercise on an unstable surface, increased the activity of the external obliques but reduced transversus abdominis activation. CONCLUSION: This study indicates that lumbar stabilization exercises on an unstable surface enhanced the activities of trunk muscles, except for the back bridge exercise.

Treatment for lateral flexion fracture dislocation of the cervical spine: report of two cases.

The injury mechanism of traumatic cervical spine injury varies, and Allen et al. divide cervical spine injuries into 6 types based on the direction of external force at the time of injury. In this report, we present 2 cases as Lateral Flexion Stage 2. A 51-year-old male (Case 1) was injured in a traffic accident. His conscious level was JCS III-200, and he was found to have a Frankel Grade of B. X-ray revealed a C5/6 fracture dislocation injury of Lateral Flexion Stage 2. We were unable to obtain good reduction. We planned to perform posterior fusion using a cervical spine pedicle screw but could not perform the procedure due to the patient's poor general condition. A 32-year-old male (Case 2) was injured as a result of being hit by a steel sheet. He had Frankel Grade D paralysis. X-ray revealed a C5/6 fracture dislocation injury of Lateral Flexion Stage 2. We did not perform manual reduction. We performed posterior fixation, anterior decompression and anterior fixation. Bone union was confirmed, and the patient was able to return to work. In cases of this type of fracture dislocation of the cervical spine, the supporting structures of the spinal column circumferentially rupture and induce high instability. Since closed reduction is sometimes difficult and involves risk, strong internal fixation might be recommended.

Femoral nerve palsy caused by a huge iliopectineal synovitis extending to the iliac fossa in a rheumatoid arthritis case.

We report on a 54-year-old woman with rheumatoid arthritis who had severe femoral nerve palsy affected by a distended synovium in the hip joint. Surgical exploration demonstrated a perforation of the iliopectineal bursa connecting with the hip joint. The patient fully recovered from femoral nerve palsy after surgery. It was considered that synovitis of the hip joint had developed following huge iliopectineal bursitis.