Adam M. Wegner

Purpose: Achieving target L1-pelvic-angle (L1PA) is heavily influenced by segmental lordosis changes during adult spinal deformity (ASD) surgery. Understanding the effect of changing each lordotic segmental level on L1PA will aid in preoperative planning and intraoperative alignment assessment in ASD. In patients undergoing ASD surgery, we aimed to evaluate the impact of segmental lordosis changes on postoperative L1PA. Methods: A retrospective cohort study (2009-24) was performed for ASD surgery patients. Inclusion criteria were: ≥5-level fusion and sagittal/coronal deformity. Primary exposure variable was change in segmental lordosis at each lumbar level. Primary outcome was the change in L1PA. Multivariable regression controlling for preoperative and change in segmental lordosis at each level was performed. Results: Of 180 patients (mean age:59 ± 19 years, 32% males), mean preoperative/postoperative L1PA were 14 ± 11° and 12 ± 9°, respectively. L1/2 : Mean change in lordosis was 7 ± 6°. For a 10° increase in L1/2 lordosis, the L1PA increased by 0.33° (β = -0.03, p = 0.684). L2/3 : Mean change in lordosis was 8 ± 8°. For a 10° increase in L2/3 lordosis, the L1PA decreased by 0.01° (β = 0.00, p = 0.991). L3/4 : Mean change in lordosis was 9 ± 8°. For a 10° increase in L3/4 lordosis, the L1PA decreased by 1.05° (β = 0.10, p = 0.086). L4/5 : Mean change in lordosis was 9 ± 8°. For a 10° increase in L4/5 lordosis, the L1PA decreased by 1.78° (β = 0.18, p = 0.001). L5/S1 : Mean change in lordosis was 11 ± 12°. For a 10° increase in L5/S1 lordosis, the L1PA decreased by 1.41° (β = 0.14, p = 0.002). Conclusion: Changes in segmental lordosis at the L4/5 level were associated with greatest decrease in L1PA following ASD surgery, followed by L5/S1 and L3/4. Changes at L5/S1 influenced the L1PA slightly less than L4/5. These findings suggest that focusing on adding lordosis at the L4/5 and L5/S1 level will result in the greatest improvement in L1PA.

Study Design: A retrospective cohort study.Purpose: To evaluate whether using antibiotic-impregnated bone graft (AIBG) enhances infection control and shortens the postoperative course of pyogenic discitis and vertebral osteomyelitis (PDVO).Overview of Literature: Surgical treatment of PDVO is indicated for neurological deficit, instability, unknown pathogen, or poorly controlled infection. The posterior-only approach is effective but requires 4–6 weeks of antibiotic treatment postoperatively. We hypothesized that AIBG used in an all-posterior approach could enhance infection control and shorten the postoperative course of PDVO.Methods: Thirty patients with PDVO of the lumbar or thoracic spine treated with transforaminal interbody debridement and fusion (TIDF) with AIBG between March 2014 and May 2022 were reviewed (AIBG group). For comparative analysis, 28 PDVO patients who underwent TIDF without AIBG between January 2009 and June 2011 were enrolled (non-AIBG group). The minimum follow-up duration was 2 years. Clinical characteristics and surgical indications were comparable in the two groups. C-reactive protein (CRP) levels and the postoperative antibiotics course were compared between the two groups.Results: Surgical treatment for PDVO resulted in clinical improvement and adequate infection control. Despite the shorter postoperative intravenous antibiotic duration (mean: 19.0 days vs. 39.8 days), the AIBG group had significantly lower CRP levels at postoperative 4 and 6 weeks. The mean Visual Analog Scale pain scores improved from 7.3 preoperatively to 2.2 at 6 weeks postoperatively. The average angle correction at the last follow-up was 7.9°.Conclusions: TIDF with AIBG for PDVO can achieve local infection control with a faster reduction in CRP levels, leading to a shorter antibiotic duration.

Background: Disorders of the hip and lumbar spine can create similar patterns of pain and dysfunction. It is unknown whether all surgeons, regardless of orthopedic or neurosurgery training, investigate and diagnose concurrent hip and spine pathology at the same rate. Methods: Data were retrieved from Taiwan’s National Health Insurance Research Database (NHIRD). Enrolled patients were stratified into hip and spine surgery at the same admission (Both), hip surgery before spine surgery (HS), or spine surgery before hip surgery (SH). The SH group was further subdivided based on whether spine surgery was performed by an orthopedic surgeon (OS) or neurosurgeon (NS), and differences in preoperative radiographic examinations and diagnoses were collected and analyzed. Results: In total, 1824 patients received lumbar spine surgery within 1 year before or after hip replacement surgery. Of these, 103 patients had spine and hip surgery in the same admission (Both), 1290 patients had spine surgery before hip surgery (SH), and 431 patients had hip surgery before spine surgery (HS). In the SH group, patients were categorized into spine surgery by orthopedic surgeons (OS) (n = 679) or neurosurgeons (NS) (n = 522). In the SH group, orthopedic surgeons investigated hip pathology with X-rays more often (52.6% vs. 38.1%, p < 0.001) and diagnosed more cases of hip disease (43.6% vs. 28.9%, p < 0.001) than neurosurgeons. Conclusions: Of patients in Taiwan’s NHIRD who had concurrent surgical degenerative hip and lumbar spine disorders who had spine surgery before hip surgery, orthopedic surgeons obtained hip images and made hip-related diagnoses more frequently than did neurosurgeons.

Background. A collapsed nonhealed vertebral fracture with endplate destruction is a challenging injury to address, as there is no single definitive treatment. We present two cases using an innovative transforaminal grafting technique to treat these patients. Case Presentation. Case 1: a 72-year-old woman had nonunion of an L1 compression fracture with destruction of both endplates. T12/L1 and L1/L2 transforaminal debridement and impaction of bone graft were performed followed by posterior instrumentation. At three years follow-up, the fusion mass between T12/L1 and L1/L2 was solid and the patient had minimal pain. Case 2: a 62-year-old woman had nonunion of an L1 burst fracture with destruction of the lower endplate. Hemilaminectomy and transforaminal interbody impaction of bone graft was performed. At three years follow-up, the patient had no back pain and a solid fusion. In both cases, local kyphosis was corrected and fusion obtained. Conclusions. Collapsed nonhealed vertebral body fractures combined with endplate destruction can be successfully treated with a one-step posterior surgery consisting of transforaminal debridement and impaction of bone graft in combination with posterior pedicle instrumentation.

To evaluate the precise objective fluoroscopic abnormalities in persons with dysphagia following anterior cervical spine surgery (ACSS). 129 patients with dysphagia after ACSS were age and sex matched to 129 healthy controls. All individuals underwent videofluoroscopic swallow study (VFSS). VFSS parameters abstracted included upper esophageal sphincter (UES) opening, penetration aspiration scale (PAS), and pharyngeal constriction ratio (PCR). Other data collected included patient-reported outcome measures of voice and swallowing, number of levels fused, type of plate, vocal fold immobility, time from surgery to VFSS, and revision surgery status. The mean age of the entire cohort was 63 (SD ± 11) years. The mean number of levels fused was 2.2 (±0.9). 11.6% (15/129) were revision surgeries. The mean time from ACSS to VFSS was 58.3 months (±63.2). The majority of patients (72.9%) had anterior cervical discectomy and fusion (ACDF). For persons with dysphagia after ACSS, 7.8% (10/129) had endoscopic evidence of vocal fold immobility. The mean UES opening was 0.84 (±0.23) cm for patients after ACSS and 0.86 (±0.22) cm for controls (P > .0125). Mean PCR was 0.12 (±0.12) for persons after ACSS and 0.08 (±0.08) for controls, indicating significant post-surgical pharyngeal weakness (P < .0125). The median PAS was 1 (IQR 1) for persons after ACSS as well as for controls. For ACSS patients, PCR had a weak correlation with EAT-10 (P < .0125). Chronic swallowing dysfunction after ACSS appears to be secondary to pharyngeal weakness and not diminished UES opening, the presence of aspiration, vocal fold immobility, or ACSS instrumentation factors. Level of Evidence: 3b

Reactive oxygen species (ROS) generated by the NADPH oxidase (Nox) enzymes are important short‐range signaling molecules. They have been extensively studied in the physiology and pathophysiology of the cardiovascular system, where they have important roles in vascular inflammation, angiogenesis, hypertension, cardiac injury, stroke, and aging. Increasing evidence demonstrates that ROS and Nox enzymes also affect bone homeostasis and osteoporosis, and more recent studies implicate ROS and Nox enzymes in both inflammatory arthritis and osteoarthritis. Mechanistically, this connection may be through the effects of ROS on signal transduction. ROS affect both transforming growth factor‐β/Smad signaling, interleukin‐1β/nuclear factor‐kappa B signaling, and the resulting changes in matrix metalloproteinase expression. The purpose of this review is to describe the role of Nox enzymes in the physiology and pathobiology of bone and joints and to highlight the potential of therapeutically targeting the Nox enzymes.

Knee injuries cause structural damage and acute inflammation that initiates the development of post‐traumatic osteoarthritis (PTOA). NADPH oxidase 4 (Nox4), a member of a family of enzymes that generates reactive oxygen species (ROS), plays a pivotal role in normal development of the musculoskeletal system, but may increase ROS production to harmful levels after joint injury. The role of ROS in both normal joint homeostasis and injury is poorly understood, but inhibition of excessive ROS production by Nox4 after joint injury could be protective to the joint, decreasing oxidative stress, and initiation of PTOA. Knee injuries were simulated using inflammatory cytokines in cultured primary human chondrocytes and a non‐invasive mouse model of PTOA in C57BL/6N and Nox4 knockout mice. There is an acute decrease in Nox4 activity within 24 h after injury in both systems, followed by a subsequent sustained low‐level increase, a novel finding not seen in any other system. Inhibition of Nox4 activity by GKT137831 was protective against early structural changes after non‐invasive knee injury in a mouse model. Nox4 knockout mice had significant differences in structural and mechanical properties of bone, providing further evidence for the role of Nox4 in development of joint tissues and biochemical response after joint injury. Nox4 plays a significant role in the acute phase after joint injury, and targeted inhibition of inflammation caused by Nox4 may be protective against early joint changes in the pathogenesis of PTOA. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2429–2436, 2019

This study is the first biomechanical research of headless compression screws for fixation of vertical shear fractures of the medial malleolus, a promising alternative that potentially offers several advantages for fixation.Vertical shear fractures were simulated by osteotomies in 20 synthetic distal tibiae. Models were randomly assigned to fixation with either 2 parallel