Masafumi Uesugi’s scientific contributions

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.

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.

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.

Tibial pilon fractures are difficult to treat. These fractures are associated with a high frequency of soft tissue complications. Therefore, two-stage surgery and less invasive surgical strategies using external fixation have been reported. The patient was a 79-year-old man. The right tibial pilon fracture was diagnosed as AO/OTA 43C3.1, Rüedi and Allgöwer type 2. He was treated with a low-profile mini-fragment plate and circular (Ilizarov type) external fixation. Herein, we report on a combination of these two methods: circular external fixator with low-profile mini-fragment plate fixation. At 18 months postoperatively, the American Orthopaedic Foot & Ankle Society Ankle-Hindfoot score was a perfect score of 100. Radiographs taken in the loading position showed no narrowing of the joint fissure. There were no soft tissue infections, no plate breakage, no bone fusion, no symptoms of plate irritation, and no need for nail extraction.

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.

An 11-year-old boy was admitted to our hospital due to severe pain in his right knee when he landed after jumping over a vaulting box. A plain X-ray image and computed tomography scan showed an avulsion fracture of the lower pole of the patella and patella alta. Furthermore, magnetic resonance imaging (MRI) revealed an articular cartilage lesion and rupture between the inferior pole of the patella and the patella tendon. We diagnosed a sleeve fracture of the patella and performed surgical treatment. Open reduction and internal fixation were performed by the pull-out technique using transosseous no. 2 MaxBraid™ (Zimmer Biomet, Tokyo, Japan) sutures. While postoperative weight-bearing was permitted, the knee joint was immobilized in a brace for four weeks. Three months of postoperative assessment revealed excellent functional outcomes.

Spinopelvic fixation (SPF) is an effective treatment method for vertically unstable pelvic ring fractures with spinopelvic dissociations (Patel et al., 2022). A heavy container fell on a 35-year-old man who was trapped and sustained injuries. His pelvic ring fracture dislocation was identified as AO Classification 61-C2.3 with rotational and vertical unstable pelvic ring; thus, crab-shaped fixation (SPF modification) was performed (Okuda et al., 2019). The pelvic fracture was fused, and the clinical outcome was good with modified Majeed score of 96. However, set-screw loosening was observed during the postoperative course. Reports of implant failures in SPF for unstable pelvic ring fractures commonly occur. However, only a few reports have demonstrated implant failure of crab-shaped fixation. Written informed consent was obtained from the patient for publication of this case report and accompanying images.

Isolated brachial muscle injuries are relatively rare injuries and reportedly occur during forced elbow extension. Though commonly conservative treatment approach is adopted, the treatment criteria remain unclear. Here, we report the case of a patient who experienced functional recovery after conservative treatment for an isolated brachial muscle injury. The patient was an 8-year-old boy whose chief complaint was left elbow pain. The injury occurred when the patient fell while playing on gymnastics bars and bruised the palmar side of his left elbow on the bar. Owing to the pain in the left elbow, the patient came to our institution. There were no clear signs of deformities or swelling in the left elbow and no obvious tenderness. X-ray and computed tomography (CT) imaging examinations revealed no signs of a fracture or dislocation, and the patient was diagnosed with left brachialis muscle rupture based on magnetic resonance imaging (MRI). Although the brachialis muscle was complete ruptured, a healing tendency was seen on body surface ultrasound examinations over time, and the patient was treated conservatively. After 3 weeks of cast immobilization, the patient underwent range of motion exercises. Two months after the injury, there were no issues with elbow joint function in daily life activities and no limitations in range of motion. Here, MRI was used to diagnose brachialis muscle rupture, and ultrasound examinations were utilized to make treatment decisions.