Could the different surgical goals of fusion and non-fusion also be achieved in combination within the same patient? Clinical and radiological outcome of hybrid cervical spine surgery.

PURPOSE: Hybrid cervical spine surgery (HS) is a novel surgical strategy wherein an artificial disc replacement is done with a cervical fusion nearby with a stand-alone titanium cage to combine the advantages in both procedures. The aim of this study was to evaluate interactions of these devices within the same patient, and to analyze, if the different goal of each implant is accomplished. METHODS: Thirty-six patients were treated surgically within a non-randomized retrospective study framework with HS. Patients were examined preoperatively followed by clinical and radiological examination at least one year postoperative. Clinical outcome was detected with NDI, VAS arm/neck, pain self-assessment questionnaires and subjective patient satisfaction. Radiological assessments included RoM, segmental lordosis, cervical lordosis of C2-C7, subsidence, ap-migration and heterotopic ossifications (HO) at the cTDR levels. RESULTS: Statistically significant improvement of all clinical scores was observed (NDI 37.5 to 5.76; VASarm 6.41 to 0.69; VASneck 6.78 to 1.48). Adequate RoM was achieved at cTDR levels. RoM in the ACDF levels was reduced statistically significant (p < 0.001), and solid fusion (> 2°) was achieved in all evaluated fusion level. Global lordosis (C2-C7) increased statistically significant (2.4° to 8.1°). Subsidence and HO at the cTDR levels did not occur. CONCLUSIONS: HS results in preservation of the segmental motion in the cTDR and fast and solid fusion in the cage cohort simultaneously. Patient safety was proven. In carefully selected cases, HS is a safe and viable treatment option by choosing the right "philosophy" level per level.

Predictive Parameters for Chêneau Brace Efficacy in Patients with Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective consecutive cohort study. OBJECTIVE: For patients with mild to moderate adolescent idiopathic scoliosis (AIS), bracing is the standard therapy to prevent progression of deformity. Still, not all patients benefit from treatment in the same way. Therefore, predictive parameters are needed to determine if patients are likely to benefit from brace therapy. METHODS: Fourty-five AIS patients treated with a Chêneau brace were evaluated retrospectively. Inclusion criteria were based on SRS-criteria. Whole spine X-rays were performed pre-brace, in-brace, and at least 6 months after termination of brace treatment. Gender, age, Risser's sign, vertebral rotation determined by Nash and Moe grading system, in-brace correction and in-brace time per day were parameters evaluated. Treatment success and failure groups were compared to determine possible predictive parameters for successful brace treatment. RESULTS: Chêneau brace treatment was successful preventing curve progression in 69%. We found significant differences between success and failure group concerning age (14 ± .22 vs 12.4 ± .4; P < .001) and Risser's sign (1.71 ± .16 vs .5 ± .17; P < .001) at beginning of brace treatment. Most significantly, initial in-brace curve correction was correlated with successful outcome after brace treatment (r = .64 (P < .001)). CONCLUSIONS: As one of few studies adhering to the criteria defined by the Scoliosis Research Society our study shows reliable predictive parameters for Chêneau brace treatment success in patients with AIS. Data shown in this paper will help to differentiate AIS patients who are likely to benefit from adequate bracing therapy from those who could rather benefit from early surgical treatment.

[The mono- and multisegmental ventral minimally invasive approach to the lumbar spine (OLIF) in lumbar deformities]. / Mono- und mehrsegmentaler ventraler minimalinvasiver Zugang zur Lendenwirbelsäule (OLIF) zur Korrektur von Deformitäten.

OBJECTIVE: Minimally invasive anterolateral approach to the lumbar spine (oblique lateral interbody fusion, OLIF) to correct lumbar deformities. INDICATIONS: Ventral release in degenerative lumbar scoliosis or segmental kyphosis and intervertebral spondylodesis. CONTRAINDICATIONS: No absolute contraindications. Relative contraindications are previous (left-sided) retroperitoneal interventions or status after peritonitis with pronounced retroperitoneal scarring. Vascular anomalies with extremely lateral common iliac vein (especially with segmentation disorders in the penultimate mobile segment). SURGICAL TECHNIQUE: Through a small skin incision in the left abdominal wall and alternating incision technique through the abdominal wall muscles retroperitoneal approach to the lateral anterior lumbar spine monosegmental or from L1-L5 multisegmental if needed. Retraction of the psoas muscle and removal of the intervertebral disc space, if necessary with resection of the anterior longitudinal ligament. Intervertebral release and interposition of an implant for ventral spondylodesis. POSTOPERATIVE MANAGEMENT: Early mobilisation after dorsal instrumentation under thrombosis prophylaxis. Light meals until the first bowel movement. Wearing a trunk stabilizing brace for up to 12 weeks, depending on the type and extent of the procedure. No limitations regarding walking distance, standing and sitting immediately postoperatively. RESULTS: In all, 15 patients with degenerative lumbar scoliosis were treated with ventrodorsal fusion surgery. The surgical anterior treatment included 1-4 segments. The access-specific complications and pre- and postoperative radiological parameters were recorded. None of the 15 left-sided retroperitoneal ventral accesses showed intraoperative or postoperative access-specific complications. A significant reduction of the anteroposterior Cobb angle from 16°â€¯± 6° preoperatively to 3°â€¯± 2° postoperatively (p < 0.001) was achieved in the entire patient population.

Revision after failed discectomy.

PURPOSE: Recurrent lumbar disc herniation is the most common complication after discectomy. Due to the altered anatomy with the presence of scar tissue, the surgical revision of already operated patients could be a surgical challenge. METHODS: We describe the microsurgical revision technique step by step with the evaluation of our own clinical results in comparison with primary lumbar disc surgeries. The clinical data are based on a clinical register with 2576 recorded primary surgeries (PD) and 592 cases of revisions (RD) with 12- and 24-month follow-up (FU). The intraoperative dura lesion rates of the surgeries between 2016 and 2018 were recorded retrospectively. Data from 894 primary disc surgeries and 117 revisions were evaluated. RESULTS: The ODI and the VAS for leg and back pain improved in both groups significantly with slightly inferior outcome of the revision group. The ODI improved from 46.3 (PD) and 45.9 (RD), respectively, to 12.6 (PD) and 22.9 (RD) at the 24-month FU. The VAS dropped down as well in both group [VAS back: 47.8 (PD) and 43.9 (RD) to 19.9 and 32.2 at the 24-month FU; VAS leg: 62.9 (PD) and 65.5 (RD) to 15.6 and 26.8 at the 24-month FU]. During the primary interventions, we observed 1.5% (11/894) and during revisions 7.7% (9/117) of dura lesions. CONCLUSIONS: There is no clear guideline for the surgical treatment of recurrent disc herniations. In most cases, a pure re-discectomy is sufficient and can be performed safely and effectively with the help of a microscope. These slides can be retrieved under Electronic Supplementary Material.

Clinical and Radiographic Outcome of Patients With Cervical Spondylotic Myelopathy Undergoing Total Disc Replacement.

STUDY DESIGN: A nonrandomized, prospective, and single-center clinical trial. OBJECTIVE: The aim of this study was to investigate the clinical and radiographic efficacy of ProDisc Vivo cervical total disc replacement (cTDR) in patients with clinical and radiographic documented cervical spondylotic myelopathy (CSM), due to degenerative changes at the index level. SUMMARY OF BACKGROUND DATA: Decompression and fusion is still the gold standard in patients with cervical myelopathy. Very limited data are available regarding the application of cTDR in patients with clinical and radiological documented CSM in context of clinical and radiographic outcomes. METHODS: Clinical outcome scores included the Neck Disability Index (NDI), Visual Analogue Scale (VAS), arm and neck pain self-assessment questionnaires as well as the Nurick grade and the Japanese Orthopaedic Association (JOA) score. The radiological outcome included the range of motion (ROM), the segmental and global (C2-C7) lordosis, and the occurrence of heterotopic ossifications. RESULTS: Eighteen consecutive patients (10 males, 8 females) with documented clinical and radiological signs of myelopathy were included in this investigation. The study population had a mean age of 52.4 years and a follow-up period of 20.3 months in average (range 3-48 months). The mean range ROM of the index level stayed consistent with 6.8° preoperatively and 7.2° (P = 0.578) at the last follow-up; the global lordosis in neutral position changed from 3.5° to 14.2° significantly (P = 0.005) in mean. The JOA score improved from 11.3 to 16.6 (P < 0.001) as well as the NDI 36.7 to 10.3 (P < 0.001) and the VAS score from 5.7/6.1 (arm/neck) to 1.3/2.0 (P < 0.001/P < 0.001). The mean Nurick grade was 1.33 preoperatively and dropped down in all cases to Nurick grade of 0 (P < 0.001). CONCLUSION: cTDR (with ProDisc Vivio) in patients with CSM yielded good clinical and radiographic outcomes and found as a reliable, safe, and motion-preserving surgical treatment option, although its indication is very limited due to numerous exclusion criteria. LEVEL OF EVIDENCE: 4.

Beneficial Effects of CpG-Oligodeoxynucleotide Treatment on Trauma and Secondary Lung Infection.

Although Streptococcus pneumoniae is usually found as a commensal in healthy individuals, it can act as a pathogen in trauma patients, causing such complications as early-onset pneumonia and sepsis. We discovered that treating mice with an A-class CpG-oligodeoxynucleotide (ODN) at 2 h after traumatic injury significantly improved mouse survival following early-onset secondary lung infection with S. pneumoniae. This study used mass cytometry (cytometry by time-of-flight) and Luminex technologies to characterize the cellular immune response to secondary S. pneumoniae lung infection at 1 and 3 d postinfection. We found increased expression of CD14, CD64, and PD-L1 on F4-80(+) and F4-80(+)CD11c(+) macrophages, CD11c(+) dendritic cells, and CD14(+)CD172a(+) cells after burn-injury and infection, supporting previous reports of innate immune cell activation in sepsis. CpG-ODN treatment at 2 h after burn-injury reversed these effects; improved pathogen clearance; and led to an increased expression of CD25, CD27, MHCII, and IL-17 on or in TCRγδ cells at 1 d postinfection. At 3 d postinfection, CpG-ODN treatment increased the expression of PD-L1 on innate cell subsets. Furthermore, we analyzed cytokine levels in lung-washout samples of TCRγδ cell-depleted (TCRγδ(-)) mice to demonstrate that the effects of CpG-ODN on cytokine expression after burn-injury and S. pneumoniae infection rely on functional TCRγδ cells. In summary, we demonstrate that cytometry by time-of-flight provides an effective strategy to systematically identify specific cellular phenotypic responses to trauma and bacterial pneumonia and to discover changes in immune system phenotypes associated with beneficial immunotherapy.

Characterization of lung infection-induced TCRγδ T cell phenotypes by CyTOF mass cytometry.

T cell receptor γδ cells are known to be the primary effector T cells involved in the response to bacterial infections, yet their phenotypic characteristics are not as well established as other T cell subsets. In this study, we used cytometry by time-of-flight mass cytometry to better characterize the phenotypic response of T cell receptor γδ cells to Streptococcus pneumoniae lung infection. Mice were infected, and cells from lung washouts, spleen, and lymph nodes were stained to detect cell-surface, intracellular, and signaling markers. We observed that infection caused a significant increase in T cell receptor γδ cells, which expressed high interferon-γ and interleukin-17A levels. Profiling T cell receptor γδ cells by cytometry by time-of-flight revealed that activated γδ T cells uniquely coexpressed cell-surface Gr-1, cluster of differentiation 14, and cluster of differentiation 274 (programmed death-ligand 1). Further classification of Gr-1 expression patterns on T cell receptor γδ cells demonstrated that Gr-1(+) T cell receptor γδ cells were the primary source of interferon-γ, whereas Gr-1(-) cells mostly expressed interleukin-17A. Gr-1(+) T cell receptor γδ cells also showed higher ζ-chain-associated protein kinase 70, p38, and 4eBP1 signaling in response to infection as compared with Gr-1(-) T cell receptor γδ cells. Taken together, Gr-1 expression patterns on γδ T cells in the lung provide a robust marker to differentiate interferon-γ- and interleukin-17A-producing subsets involved in the early immune response to bacterial pneumonia.

Radiation exposure induces inflammasome pathway activation in immune cells.

Radiation exposure induces cell and tissue damage, causing local and systemic inflammatory responses. Because the inflammasome pathway is triggered by cell death and danger-associated molecular patterns, we hypothesized that the inflammasome may signal acute and chronic immune responses to radiation. Using a mouse radiation model, we show that radiation induces a dose-dependent increase in inflammasome activation in macrophages, dendritic cells, NK cells, T cells, and B cells as judged by cleaved caspase-1 detection in cells. Time course analysis showed the appearance of cleaved caspase-1 in cells by day 1 and sustained expression until day 7 after radiation. Also, cells showing inflammasome activation coexpressed the cell surface apoptosis marker annexin V. The role of caspase-1 as a trigger for hematopoietic cell losses after radiation was studied in caspase-1(-/-) mice. We found less radiation-induced cell apoptosis and immune cell loss in caspase-1(-/-) mice than in control mice. Next, we tested whether uric acid might mediate inflammasome activation in cells by treating mice with allopurinol and discovered that allopurinol treatment completely blocked caspase-1 activation in cells. Finally, we demonstrate that radiation-induced caspase-1 activation occurs by a Nod-like receptor family protein 3-independent mechanism because radiation-exposed Nlrp3(-/-) mice showed caspase-1 activation profiles that were indistinguishable from those of wild-type mice. In summary, our data demonstrate that inflammasome activation occurs in many immune cell types following radiation exposure and that allopurinol prevented radiation-induced inflammasome activation. These results suggest that targeting the inflammasome may help control radiation-induced inflammation.

Hip resurfacing requires larger acetabular cups than conventional hip replacement: a comparative analysis of 100 hips, based on radiographic templating.

Acetabular bone loss is a matter for concern in hip resurfacing arthroplasty (HRA), as preservation of the femoral head and neck might demand a larger acetabular cup than in total hip arthroplasty (THA). Using radiographic templating, the cup size required for either THA or HRA was calculated on 100 pelvic films. First, the cup size was determined based on the dimensions of the acetabulum. Then, the cup size for HRA was evaluated taking into account the dimensions of the femoral head/neck. The average cup size required for HRA was larger than for THA (delta + 1.1 mm). The cup size for HRA and THA was similar in 49% of hips; in 51% of the hips the cup required for HRA was larger: one size larger in 31%, two sizes larger in 18% and three sizes larger in 2% of the cases. The greatest difference and highest bone loss were observed for the large sizes (between 52 and 56 mm) and thus predominantly in men (delta + 15 mm male, delta + 0.7 mm female). This study shows that HRA requires a larger acetabular cup in more than 50% of the cases compared to THA. When planning HRA surgeons should remember that cup size is determined by the size of the matching femoral component and that size difference with THA increases with increasing hip sizes.

Revision of hip resurfacing arthroplasty with a bone-conserving short-stem implant: a case report and review of the literature.

INTRODUCTION: Suitable treatment of early failure of total hip replacement is critical in younger patients, as bone stock is lost and the functional outcome is impaired. CASE PRESENTATION: We report the case of a 56-year-old Caucasian woman with early failure of hip resurfacing arthroplasty. While revision is usually performed with a conventional hip implant, this case report describes for the first time a revision procedure with a bone-conserving short-stem hip implant. CONCLUSIONS: Our approach allows further conservation of femoral bone stock and provides a long-term solution to the patient, which maintains the possibility of using a conventional hip implant should a second revision become necessary.

The accuracy of digital templating: a comparison of short-stem total hip arthroplasty and conventional total hip arthroplasty.

PURPOSE: Selection of the correct femoral stem size is crucial in total hip arthroplasty for an uncomplicated implantation and good initial stability. Pre-operative templating has been shown to be a valuable tool in predicting the correct implant size. For short-stem total hip arthroplasty (SHA), which recently is increasingly used, it is unknown if templating can be performed as reliable as conventional total hip arthroplasty (THA). METHODS: A total of 100 hip arthroplasties, 50 with SHA and 50 with THA, were templated by four orthopaedic surgeons each. The surgeons had different levels of professional experience and performed a digital template of the acetabular and femoral component on the pre-operative radiographs. The results were compared with the truly inserted implant size. RESULTS: For the femoral stems the average percentage of agreement (± 1 size) was 89.0 % in SHA and 88.5 % in THA. There was no significant difference among surgeons in the accuracy of templating the correct stem size and no significant difference between templating SHA and THA. For the acetabular component the average percentage of agreement (± 1 size) was 75.8 %. However, the more experienced surgeons showed a significant higher accuracy for templating the correct cup size than the less experienced surgeons. CONCLUSION: Digital templating of SHA can predict the stem sizes as accurately as conventional THA. Therefore digital templating is also recommendable for SHA, as it helps to predict the implant size prior to surgery and thereby might help to avoid complications.

Biomechanical evaluation of different offset versions of a cementless hip prosthesis by 3-dimensional measurement of micromotions.

BACKGROUND: Cementless hip prostheses with different offsets are frequently used to restore the rotation center of the hip. However, a rising offset is theoretically associated with a potential risk for increased interface stresses and early loosening. METHODS: To assess this potential risk for cementless stems, the primary stability of the CLS Spotorno stem was examined with respect to three different femoral neck versions (125°, 135° and 145°) measuring 3-dimensional micromotions. For this purpose 18 stems were implanted in composite femurs and tested dynamically using physiological loading conditions considering the necessary adaptation according to the different offsets. Additionally the deformations at the surface of the composite femur were recorded to draw conclusions about the tendency for stress shielding. FINDINGS: The micromotions of the different offset versions were not significantly different. The highest values were obtained at the tip of the stems, even exceeding the critical limit for osseous integration of 150µm. Compared to untreated composite femurs the alteration of the deformations at the surface remained relatively low. A significant difference was only observed in the ventral measurement points. INTERPRETATION: According to the measured micromotions no offset version of the CLS Spotorno can be declared as superior. The assumption that the varus version is characterized by extended interface stresses could not be confirmed. Furthermore, it could be demonstrated that according to the principle of proximal load transfer of the CLS Spotorno stem an osseous integration of the distal part cannot be expected and that the risk for stress shielding appears to be relatively low.