Anterior Plate Research Articles

A prospective cohort study: promising results with minimally invasive plate osteosynthesis of anterior bridge plating in adult humeral shaft fractures.

Adult humeral shaft fractures have traditionally been managed conservatively, but surgical intervention is considered for displaced fractures or when conservative treatment is unlikely to be successful. The optimal surgical approach remains controversial, with open reduction and internal fixation (ORIF) using plates and screws considered the gold standard. However, concerns about soft tissue damage have led to the development of less invasive techniques, such as anterior bridge plating using minimally invasive plate osteosynthesis (MIPO). This study aimed to evaluate the outcomes of MIPO for humeral shaft fractures. A prospective cohort study included 43 patients who underwent anterior bridge plating with MIPO for closed, displaced humeral shaft fractures. Forty patients had full follow-up (functional and radiological) and three patients were lost to follow-up. Fractures were classified using the AO classification system. Surgical technique involved incision, reduction, and fixation with locking compression plates. Follow-up assessments were conducted at various intervals, and functional outcomes were evaluated. Fracture union was achieved in 38 of 40 patients (95%). Two patients required secondary bone grafts for non-union. The mean time to union was between 12 and 16 weeks. Excellent shoulder function was observed in 82.5% of patients, and excellent elbow function in 77.5%. The range of motion on the operated side differed statistically significantly from the non-operated side but was not clinically significant. MIPO with anterior bridge plating is a viable option for the surgical management of humeral shaft fractures. It offers good fracture healing rates and satisfactory functional outcomes and avoids extensive soft tissue dissection associated with ORIF. Level of evidence: II.

Cervical Lordosis Correction and Segmental Height in Anterior Cervical Surgeries; The Role of Implant Choice

This study aims to compare the impact of three surgical techniques-stand-alone cage placement (SAC), anterior cervical plate (ACP) fixation, and total disc replacement (TDR)-on cervical lordosis restoration and segmental height after anterior cervical discectomy at C5-6 level. To eliminate the effect of lordosis between different levels, patients operated on at the same level were included in the study. Restoring cervical lordosis is crucial for improving patient outcomes, including pain reduction and preventing mechanical complications. A retrospective screening of 89 patients who underwent single-level C5-6 surgery between 2011 and 2021 was analyzed. Patients were categorized into three groups based on the surgical technique used: SAC, ACP, or TDR. Lordotic angles and segmental heights were measured preoperatively, first-month follow-up, and at the 24-month follow-up. Statistical analysis was conducted using the Wilcoxon Signed Rank test and ANOVA, with a significance threshold set at P<.05. All three techniques resulted in significant early and late postoperative increases in both global and segmental lordosis. The early postoperative height gain was most pronounced in the ACP group. However, no significant differences in lordosis or height preservation were observed among the groups at the 24-month follow-up. These findings align with previous studies, indicating comparable long-term outcomes across these surgical approaches. Stand-alone cage placement, anterior cervical plate fixation, and total disc replacement all effectively restore cervical lordosis and segmental height after anterior cervical discectomy at the C5-6 level. Despite early differences, the long-term results were similar, suggesting that the choice of technique should be based on individual patient needs and specific surgical considerations.

Two psammobiont species of Anomalohalacarus (Acari, Halacaridae) from South Korea.

The genus Anomalohalacarus Newell, 1949, which is known to occur exclusively inhabiting sand, has not been previously reported from Korea. During a recent survey of the meiofauna from several intertidal sandy beaches in South Korea, we found both sexes of two psammobiont halacarids, Anomalohalacarusangustus sp. nov. and A.biformis Abé, 1996. Both species are similar to each other in sharing an undivided posterior dorsal plate, three and two setae on the anterior and posterior epimeral plates, respectively, three bipectinate setae on tibia IV, and four ventral setae on tarsus I. However, A.angustus sp. nov. is distinguished from A.biformis by the absence of areolae posteriorly on the anterior dorsal plate, a much more slender posterior dorsal plate, a pair of subgenital setae on the genital foramen in females, and seven branched perigenital setae on the genitoanal plate in males. The feature of branched perigenital setae in males is reported for the first time in the genus Anomalohalacarus. The Korean specimens of A.biformis agree well with the original description from Japan, except for the number of ventral bipectinate setae on tibia II. This study presents (re)descriptions of both species with detailed illustrations and provides a dichotomous key to Anomalohalacarus species, including the new species, based on morphological characters. The genus Anomalohalacarus is reported for the first time in South Korea.

Comparative study on anterior pelvic plating and pubic ramus screw fixation for straddle fracture: a matched-pair outcome analysis.

Straddle fractures involving both the superior and inferior rami often require surgical fixation due to instability. This study compared the clinical and radiological outcomes of pubic ramus screw fixation (PRSF) and anterior pelvic plating (APP) for the treatment of these fractures to identify the superior method. A retrospective analysis was conducted on 70 patients (37 males, 33 females; average age 47.6 years) treated surgically for straddle fractures at two Level 1 trauma centres between May 2017 and August 2022. The patients were divided into two groups, where 26 underwent PRSF and 44 underwent APP. The groups were matched based on preoperative characteristics such as age, sex, body mass index, injury mechanism, and severity. The key variables analysed included operation time, blood transfusion volume, early weight-bearing capability, and complication and reoperation rates. After matching, PRSF was associated with a shorter operative time (71.0min vs. 118.3min for APP, p < 0.0009) and lower blood transfusion requirements (0 units vs. 1 unit, p < 0.0001). Postoperatively, 61.5% of PRSF patients tolerated early weight-bearing, compared to none in the APP group. However, in two cases, PRSF could not be performed due to severe comminution or anatomical limitations, necessitating conversion to APP. Complication rates were similar between the groups (30.8% for PRSF vs. 27.3% for APP, p = 0.93). PRSF demonstrated advantages, such as shorter operative time, reduced blood transfusions, and earlier weight-bearing. However, APP remains valuable for complex fracture patterns. Treatment should be individualized based on fracture complexity and patient-specific factors to optimize outcomes.

Biomechanical comparison of using traditional and 3D-printed titanium alloy anatomical assembly thin anterior plating under three patellar fracture conditions

ABSTRACT This study attempted to understand the biomechanics of using 3D-printed anatomical assembly thin bone plate (AATBP) and anterior star-shaped plating (ASP) under different patellar fractures. The transverse (C1), transverse plus second fragment (C2) and complex (C3) patella fractures were defined for performing the dynamic cyclic load test and finite element (FE) analysis. The AATBP was fixed onto the patella after adjusting the total fixation height using a ratchet mechanism and providing holding power hooks. The ASP contoured the plate/distal legs based on the patella surface curvature and generated an additional drill guide to avoid screw interference. The average ASP fixation fracture gaps were significantly larger than the AATBP fixation. FE analysis showed that the AATBP biomechanical performance was better than the ASP fixation for different patella fractures. The 3D-printed AATBP can be used effectively for different patella fractures without screw interference and demonstrated greater stability for comminuted patellar fractures.

Biodiversity study of the genus Bysmatrum from the South China Sea and France reveals a new benthic dinoflagellate, Bysmatrum ingrilense sp. nov. (Peridiniales, Dinophyceae)

ABSTRACT The dinoflagellate genus Bysmatrum is an unusual member of the Peridiniales and cannot be attributed to any known family. Bysmatrum differs from typical peridinialean genera in that the second and third anterior intercalary plates are separated and both antapical plates are asymmetrical. Currently, Bysmatrum encompasses six epibenthic or tide-pool species, but information on their genetic diversity and biogeography remains limited. In the present study, we obtained five strains of Bysmatrum from the South China Sea by isolating single cells and three strains from Ingril, a French Mediterranean lagoon by incubating sediments. Strains from Ingril Lagoon displayed the plate formula Po, cp, X, 4′, 3a, 7′′, 6C, 4S, 5′′′, 2′′′′. They also exhibited an elongated nucleus in the hypocone and a type B eyespot. Smooth and spherical cysts were produced in culture. Small and/or partially large subunit ribosomal DNA sequences were obtained for all eight strains. Molecular phylogeny was inferred using these concatenated sequences through maximum likelihood and Bayesian inference methods. Bysmatrum granulosum and B. subsalsum were identified from Thailand and China for the first time, each of them comprising of two ribotypes. Bysmatrum ingrilense sp. nov. was monophyletic and closest to B. subsalsum ribotype B. Pinnatoxin and related toxins were examined in two strains of Bysmatrum ingrilense by LC-MS/MS, but none were detected. Our results highlight that the diversity of Bysmatrum might be underestimated.

Clinical outcome of surgically treated displaced acetabular fractures with central dislocation using combined anterior and medial plating.

Acetabular fractures are complex articular fractures with a big challenge for orthopaedic surgeons. Surgically managed displaced fractures carry favourable outcomes, especially if the articular surface is reduced accurately. This study aims to assess the clinical outcomes of surgically fixed displaced acetabular fractures with central dislocation using combined anterior and medial plating. We have retrospectively evaluated sixteen patients, who had surgically managed displaced acetabular fractures with central dislocation at our institute. All patients underwent open reduction and internal fixation using combined anterior and medial plating via the Kocher-Langenbeck, the ilioinguinal, or the Stoppa approach. The functional outcome was assessed using the Harris Hip score. Our study includes sixteen patients (12 males, 4 females) with a mean age of 35 years (range: 15-53 years). The mean follow-up was 7.8 years (range: 5-13 years). Functional outcomes were good to excellent in 12 (80%) patients and fair in 3 (20%) patients. At the final follow-up, the solid union had been achieved in all fractures, the mean HHS was 88.84 ± 7.61. Early reduction and surgical fixation of displaced acetabular fractures with central dislocation using combined anterior and medial plates appear to have good clinical outcomes.

Ligation of anterior ethmoidal artery nasal branch: anatomical-based management of recalcitrant epistaxis.

Recurrent epistaxis, despite conservative therapies (i.e. nasal packing or direct vessel coagulation), is generally treated with ligation of the sphenopalatine artery (SPA). Indeed, the rationale behind SPA ligation lies in its ability to disrupt arterial blood supply to the nasal mucosa, thereby reducing the likelihood of recurrent bleeding episodes (1). Nevertheless, in some cases, nosebleeds persist despite appropriate SPA ligation, opening discussion of the anterior ethmoidal artery (AEA) contribution in recalcitrant epistaxis that, for some authors, is up to 28.8% (2). From an anatomical point of view, the AEA leaves the orbital cavity and passes the ethmoidal roof through the ethmoidal canal, before entering inside the anterior cranial fossa via the lateral lamella (3). Endocranially, the AEA gives posterior branches which vascularize the anterior cribriform plate, whereas its many trunk continues anteriorly and divides into two branches: the anterior meningeal branch, and a second vessel that enters inside the nasal fossa through the cribroethmoidal foramen located 2.86 ± 1.93 mm (range, 1-7 mm) (4) anteriorly to the first olfactory phylum, giving rise to the so-called nasal branch (NbAEA) (5).

Diagnosis and Treatment of Cervical Spine Fractures in Children

Background. Cervical spine injuries in children are relatively uncommon and account for approximately 1.5% of trauma admissions. The aim of our study was to determine the incidence and patterns of pediatric cervical spine fractures in a single Trauma Center over the last decade.Material and methods. The hospital’s medical database was queried for data from the period between January 2014 and December 2023. An initial search revealed that 511 patients had been hospitalized with neck injuries in that time frame. Among these records, we identified 24 patients with a fracture of the cervical spine. The inclusion criteria were: (1) age under 18 yo, (2) fracture of the cervical spine (3) follow-up of at least 6 months. A thorough analysis was performed, including injury mechanism, diagnosis, medical procedures and final outcome., A Neck Disability Index (NDI) was assessed for all patients at the six months’ follow-up visit to evaluate treatment outcomes.Results. The study group consisted of 14 boys and 10 girls aged 4.6 to 18 years (average age 14.2). We diagnosed one case of an isolated C1 fracture, six C2 fractures, two C4 fractures, two C5 fractures, two C7 fractures, and nine cases of multiple spinal fractures. Additionally, we diagnosed two cases of cervical spine dislocation: one of right-sided rotational dislocation of C6/C7 and one of complete dislocation of C2/C3. Eight patients were treated surgically by open reduction combined with anterior plate fixation. Four patients were treated using a halo vest. Eleven patients were treated conservatively: six using a Minerva orthosis, four with a cervical-thoracic orthosis, and one with a rigid cervical collar. The highest NDI values were encountered in the group of patients with concomitant intracerebral injury, where the mean value was 18.6/45 (12-26/45). The mean NDI score for the remaining patients was 4/45 (0 - 9/45).Conclusions. 1. The incidence of cervical spine fractures in children is low. 2. Most cervical spine injuries in children are treated conservatively with good outcomes. 3. Both conservative and surgical treatment of cervical spine fractures in children produces good results 4. Computed Tomography remains the gold standard for diagnosing cervical spine fractures in children. 5. The halo-vest in pediatric patients suffering from C2 fractures was well tolerated and provided good outcomes. 6. Surgical treatment of lower cervical fractures by open reduction with anterior fusion is efficient in terms of fusion status and patient satisfaction. 7. Prospective, randomized, multicenter studies are required to assess the epidemiology, methodology, and treatment effects of cervical spine fractures in children.

Glyptothorax pongoensis, a new species of rheophilic catfish (Sisoridae) from the Brahmaputra River drainage, Nagaland, India

ABSTRACT Glyptothorax pongoensis, sp. n. is described from the Yongmon River in Nagaland, India. The new species can be distinguished from its congeners in the Indian subcontinent by the following combination of characters: an ovate-shaped thoracic adhesive apparatus with skin ridges present over the entire apparatus, including the subulate-shaped median depression; presence of plicae on the ventral surface of the pectoral fin spine and the first ray of the pelvic fin; W-shaped anterior nuchal plate element; dorsal-fin origin nearer to the snout tip than to the origin of the adipose fin; posterior margin of dorsal spine rugose with 4–5 ridges, tuberculate skin, and nasal barbel not reaching eye when adpressed. http://www.zoobank.org/urn:lsid:zoobank.org:pub:5D71008D-5D28-4C77-9FA2-D5074DDA7BC9

Revision Surgery after Single Level Anterior Cervical Discectomy and Fusion With Plate vs Stand-Alone Cage over 2 to 5 Year Follow-Up.

retrospective study. To investigate the incidence of all-cause revision surgery between plated vs stand-alone cage constructs for single level ACDF. We retrospectively analyzed a commercial insurance claims database. Patients 18-65years-old were included if they underwent single-level inpatient ACDF (defined with CPT codes) from 2010 - 2018, with a minimum of 2-year continuous insurance enrollment. The primary independent variable was the use of anterior plating vs zero profile device or stand-alone cage. Synthetic (ie, metal, PEEK, etc.) vs allograft interbody was a secondary independent variable. The primary outcome variable was revision cervical arthrodesis after the index operation. In total, 21092 patients undergoing single-level inpatient ACDF were included. 10.0% received a stand-alone cage during the index operation. Mean follow-up duration was 4.5years. Revision arthrodesis occurred in 8.2% of patients overall, at a mean of 2.4years after the index surgery. Patients with anterior plating had a lower rate of all-cause revision surgery in unadjusted (overall rate 8.1% vs 9.6%, P = 0.0185) and adjusted analysis (OR 0.78, P = 0.0016) vs stand-alone cages. Patients with stand-alone cages had higher rates of revision with a posterior approach than did patients with plated constructs. In sub-analysis, the combination of a stand-alone interbody device with an allograft had significantly higher odds of revision than other combinations of devices. Among commercially insured patients ≤65years-old undergoing single-level ACDF, anterior plating was associated with a reduced incidence of revision surgery compared to stand-alone cages within the follow up period of our study.

The use of ultrasound to predict flexor tendinopathy after anterior locking plating of the distal radius.

This study compares ultrasound to clinical and radiographic measurements for assessing tendon pathology associated with distal radial anterior locking plates. A total of 46 patients undergoing removal of a distal radial plate had a preoperative clinical examination, radiographs and ultrasound evaluation to detect evidence of tendon irritation. Gross changes to the tendon were assessed during plate removal. In total, 32 patients demonstrated clinical abnormality. Soong 2 position was noted in 13 patients. Ultrasound revealed tenosynovitis in nine patients, tendon fibrillation or thickening in four patients and a single case of partial discontinuity. Intraoperative assessment revealed tenosynovitis in 28 patients and tendon fibre discontinuity in eight patients. Ultrasound findings were not predictive of intraoperative tenosynovitis and discontinuity. A relationship was noted between higher Soong grade, especially grade 2, and intraoperative presence of tenosynovitis, as well as Soong grade and amount of soft-tissue coverage. This study negates our hypothesis that ultrasound is useful for identifying tendinopathy after distal radial anterior plate fixation.Level of evidence: II.

Anterior Sacroiliac Fracture Dislocation: A Comparative Radiologic analysis of Crescent Fractures in Pelvic Ring Injuries: A Retrospective Study.

Background and Objectives: Anterior sacroiliac fracture dislocation (ASFD), also known as locked pelvis, is a rarely reported diagnosis. The types of ASFDs are often misdiagnosed as lateral compression fractures due to the presence of crescent fractures. In this study, we distinguished ASFD from lateral compression fractures (LC 2) and studied their characteristics. Materials and Methods: This is a retrospective study involving patients from a Level 1 trauma center. Fifty-nine patients under the age of 65 years with crescent fractures caused by a high-energy mechanism were investigated. Results: The incidence of ASFD was 25% (15 of 59) in patients with crescent fractures. Among the 15 patients, 6 had override of the ilium over the sacrum, inhibiting reduction in the sacroiliac joint. Pre-operative radiographic evaluations revealed that vertical displacement of the ASFD was larger than that of lateral compression fracture (LC 2) in the outlet view (mean 9.5 vs. 1.9 mm, p = 0.013), and the pelvic asymmetry ratio was larger in ASFD (mean 7.8 vs. 4.1, p = 0.006) in the pelvis AP view. All patients achieved union after surgery. Post-operative radiography showed no significant vertical displacement difference. There was no difference in vascular injury or hemodynamic instability requiring embolization or preperitoneal pelvic packing (PPP) between the two groups. Conclusions: Patients with ASFD have greater vertical displacement and asymmetry compared to patients with LC 2 fractures. These fractures must be distinguished for appropriate reduction and anterior plate fixation.

Hypoxia-sonic hedgehog axis as a driver of primitive hematopoiesis development and evolution in cavefish

The teleost Astyanax mexicanus consists of surface dwelling (surface fish) and cave dwelling (cavefish) forms. Cavefish have evolved in subterranean habitats characterized by reduced oxygen levels (hypoxia) and exhibit a subset of phenotypic traits controlled by increased Sonic hedgehog (Shh) signaling along the embryonic midline. The enhancement of primitive hematopoietic domains, which are formed bilaterally in the anterior and posterior lateral plate mesoderm, are responsible for the development of more larval erythrocytes in cavefish relative to surface fish. In this study, we determine the role of hypoxia and Shh signaling in the development and evolution of primitive hematopoiesis in cavefish. We show that hypoxia treatment during embryogenesis increases primitive hematopoiesis and erythrocyte development in surface fish. We also demonstrate that upregulation of Shh midline signaling by the Smoothened agonist SAG increases primitive hematopoiesis and erythrocyte development in surface fish, whereas Shh downregulation via treatment with the Smoothened inhibitor cyclopamine decreases these traits in cavefish. Together these results suggest that hematopoietic enhancement is regulated by hypoxia and Shh signaling. Lastly, we demonstrate that hypoxia enhances expression of Shh signaling along the midline of surface fish embryos. We conclude that hypoxia-mediated Shh plasticity may be a driving force for the adaptive evolution of primitive hematopoiesis and erythrocyte development in cavefish.

Risk factors for delayed bone union in opening wedge high tibial osteotomy.

The purpose of this study was to investigate the relationship between patient demographics and potential intraoperative factors and delayed bone union in opening wedge high tibial osteotomy (OWHTO). A retrospective review of 65 patients (37 females, 28 males; mean age: 60.1±10.1 years; range, 44 to 77 years) who underwent OWHTO using an angle-stable implant with beta-tricalcium phosphate gap filling between September 2016 and October 2019 was conducted. The osteotomy site was divided into five zones from the lateral hinge on anteroposterior radiographs, and we defined the zone in which bone healing was observed. The bone union area was assessed according to this definition at three, six, nine, and 12 months after surgery, and bone union was defined as union at the fourth zone or greater. A generalized estimating equations approach was employed to investigate longitudinal data pertaining to bone union area as a dependent variable. In addition, the association of bone union at six months postoperatively and predictors were evaluated using cross-sectional statistical methods. The categorical predictors included in the models were smoking, diabetes, hinge fracture, and autologous osteophyte grafting. The continuous variables included in the models were age, body mass index, opening gap width, and plate position. Smoking (odds ratio [OR]=0.478, p<0.01), large opening gap width (OR=0.941, p=0.014), and anterior plate placement (OR=0.971, p<0.01) were significantly associated with decreased bone union area. Union rate at six months in smokers was significantly lower compared to nonsmokers (16.6% and 67.8%, respectively; OR=0.10, p=0.023). Area under the curve in the receiver operating characteristic analysis for bone union at six months was 0.60 for gap width and 0.63 for plate placement. Smoking, large opening gap width, and anterior plate placement are risk factors for delayed bone union after OWHTO. Surgeons should avoid anterior placement of the plate and carefully consider other options for smokers and those who require a large correction.

A new weigeltaspid (Heterostraci) from the Early Devonian of Nunavut, Canadian Arctic, Canada, with comments on the relationships of the weigeltaspids

ABSTRACT A new weigeltaspid heterostracan, Orthogoniaspis amnicus nov. sp. represents the first weigeltaspid reported from the Early Devonian Peel Sound and Snowblind Bay formations, Nunavut, Canadian Arctic. One partially articulated specimen shows for the first time that while the main plates of the dorsal shield abutted each other the orbital, pineal and rostral plates were separated by bands of tesserae. The similarity of this arrangement to that of the corvaspids, particularly the presence of dorsal lateral plates and bands of tesserae separating the anterior plates suggests a sister-group relationship, as no other heterostracans share this arrangement. Arctic weigeltaspids range from the late Ludlow to the late Lochkovian (O. amnicus nov. sp.), which is earlier than the related European taxa suggesting an Arctic centre of development for the weigeltaspids, as has been suggested for other heterostracan taxa.

A meta-analysis comparing complications of anterior versus dorsal osteotomy and plating for distal radial malunions.

This systematic review and meta-analysis compare the incidences of complications, reoperations and hardware removal between anterior and dorsal plating after corrective osteotomy for dorsally angulated distal radial malunions. A total of 403 patients were included; 253 patients underwent anterior corrective osteotomy and 150 underwent dorsal corrective osteotomy. Mean follow-up was 30 months. Anterior plating was associated with fewer reoperations (9% vs. 28%), less hardware removal (3% vs. 18%) and comparable major complications (5% vs. 6%) compared to dorsal plating. The adjusted model showed a significant reduction (approximately 85%) in the odds of reoperation and hardware removal in the anterior group. There was no difference in major or minor complications between the groups. Surgeons should be fully aware of the increased risks when using dorsal plate fixation after corrective osteotomy for dorsally angulated distal radial malunions.

Posterior Wall Fragments in Acetabular Both-Column Fractures: Morphology, Type, and the Significance of its Projection.

Most both-column acetabular fractures are combined with posterior wall fragments. However, the morphology of this posterior wall is varied, and how to fix this posterior wall remains a controversial topic. To investigate the morphological characteristics of posterior wall fragments of both-column acetabular fractures and select corresponding fixation methods. Data from 352 patients with acetabular fractures admitted to the level one trauma centre in our hospital between January 2006 and December 2022 were collected. The morphology of posterior wall fragments was observed and analyzed in 83 cases of both-column acetabular fractures and classified according to the consistency of posterior wall morphology. A fracture map of the posterior wall was created on a normal template according to the three morphological types of posterior wall fragments. Finally, the high-incidence area of the posterior wall fracture was projected onto the iliac fossa and the medial side of the posterior column to guide the fixation of the posterior wall fragment using the anterior intrapelvic approach. Fractures were divided into four types: I, large posterior wall fragment which was high in the ilium bone (34 cases, 41.0%); II, posterior wall fragment in the acetabular parietal region (18 cases, 21.7%); III, posterior wall marginal fracture (10 cases, 12.0%); and IV, non-combined posterior wall fracture (21 cases, 25.3%). The most common morphologies of the posterior wall fragments of the first two types were mapped and projected onto the anterior iliac inner plate and medial side of the posterior column, where the corresponding area could be used to guide the insertion of the internal fixation. Both-column acetabular fractures combined with posterior wall fractures can be divided into four types according to the morphology of the posterior wall fragment. Understanding the corresponding three-dimensional morphology and projection position of different types of these fragments can help surgeons determine the position and orientation of internal fixation of posterior wall fractures.

Do we need another screw? Sacroiliac screw fixation in open-book pelvic ring injuries (APC type II).

To compare anterior plate fixation (SP fixation) both alone and in combination with an additional posterior sacroiliac screw (SP+SIS fixation) as a treatment for pelvic ring injuries with widening of the pubic symphysis and disruption to the anterior sacroiliac ligaments. To find studies with pelvic ring injuries (APC II; B2.3d) and SP or SP+SIS fixation, a systematic literature review was conducted by searching four databases. A protocol was published a priori at Open Science Framework (https://doi.org/10.17605/OSF.IO/3YHAV). Exclusion criteria included perineal injuries, chronic instability of the symphysis, complete sacroiliac separation, and pediatric patients (age <18 years). Primary outcomes of interest were defined as implant failure, health-related quality of life, and revision rate. Altogether, 1861 studies were screened, and 40 studies qualified for full-text analysis. In total, 14 studies (two surveys, six biomechanical studies, and six retrospective clinical studies) were included. The surveys revealed that surgeons who had more recently begun practicing were more likely to use posterior fixation (SP+ISS). The biomechanical studies were heterogenous and did not yield a uniform pattern. In clinical studies, 117 patients (45%) received SP fixation, and 142 patients (55%) received SP+SIS fixation. Complications occurred in 31 SP patients (30%) and in five SP+SIS patients (3.5%). A high risk of bias was uncovered, and reporting was found to be incomplete. SP+SIS may have the potential to improve outcomes, but the evidence remains too inconclusive to draw reliable recommendations.

Implantation of S1AIS has priority as a sacroiliac joint fixation technique.

The sacral alar-iliac screw (SAIS) fixation technique has evolved from spinopelvic fixation which originated from S2AIS to sacroiliac joint fixation, with more reports regarding its application of S2AIS than S1AIS. However, there is a lack of comparative evidence to determine which technique is superior for sacroiliac joint fixation. This study aimed to determine which of the screws was superior in terms of implantation safety and biomechanical stability for sacroiliac joint fixation. CT data of 80 normal pelvises were analyzed to measure the insertable range, trajectory lengths and widths of both S1AIS and S2AIS on 3D reconstruction models. Φ 6.5mm and 8.0mm screws were implanted on the left and right sides of fifty 3D printed pelvic models respectively to observe for breach of screw implantation. Ten synthetic pelvis models were used to simulate type C Tile injuries, and divided into 2 groups with an anterior plate and posterior fixation using one S1AIS or S2AIS on each side. The stiffness and maximum load of the plated and fixated models were measured under vertical loading. The trajectory lengths and widths of the S1AIS and S2AIS were similar (p > 0.05) and there was no breach for Φ 6.5mm SAIS. However, both the insertable range and trajectory length on the sacral side of S2AIS (234.56 ± 10.06mm2, 40.97 ± 2.81mm) were significantly less, and the breach rate of the posterior lateral cortex of the Φ 8.0mm S2AIS (46%) was significantly higher than the S1AIS (307.55 ± 10.42 mm2, 42.16 ± 3.06mm, and 2%, p < 0.05). The stiffness and maximum load of S2AIS were less than S1AIS but the difference was not statistically significant (p > 0.05). S1AIS and S2AIS have similar screw trajectories and stability. However, S1AIS has a larger insertable range, less breach of the posterior lateral sacral cortex and longer trajectory length on the sacral side than S2AIS, which indicates S1AIS has higher implantation safety and a trend of better mechanical performance over S2AIS for sacroiliac joint fixation. Furthermore, S2AIS with an excessively large diameter should be used with caution for sacroiliac joint fixation.