Plate Placement Research Articles

Dual plate fixation results in improved union rates in comminuted distal femur fractures compared to single plate fixation

PurposeThe treatment of distal femur fractures with extensive metaphyseal comminution is frequently complicated by high rates of nonunion and varus collapse. Dual plating with lateral and medial locking plates for these types of fractures has shown promising results in the recent literature. We hypothesize that dual plating of comminuted distal femur fractures leads to higher union rates and lower revision rates compared to an isolated lateral locking plate. MethodsA retrospective medical chart review between January 2015 and December 2017 was conducted. Inclusion criteria included patients 18 years of age and older who sustained a complex distal femur fracture (AO/OTA 33-C2/33-C3 or periprosthetic fracture with significant metaphyseal comminution) and at least 6 months of follow up. Patients with simple fracture patterns, alternative fixation methods, and inadequate follow up were excluded. All patients in the single plating group were treated with a lateral distal femoral locking plate using a lateral approach. In the patients treated with dual plating, an extensile parapatellar approach was utilized for fracture reduction and placement of an adjunctive medial plate. Demographic information, fracture types, injury severity score (ISS), medical comorbidities, type of surgical fixation, union rates, complications, knee range of motion, time to follow up, and need for revision surgery were extrapolated from the medical charts for analysis. ResultsTwenty-one patients were included in the study. Thirteen patients underwent single plate fixation and 8 underwent dual plate fixation. There were no significant differences in demographics, number of co-morbidities, fracture classification, or ISS between single and dual plate groups (p > 0.05 for all). There was a statistically significant difference in union rates between the single plate group (6 nonunions, 4 unions, and 3 delayed unions) and the dual plate group, with no nonunions or delayed unions (p = 0.0049). Although not statistically significant, 4 patients treated with single plating underwent revision ORIF, compared to none in the dual plating group (p = 0.13). There were no significant differences in time to follow up, time to full weight bearing, or infection rates (p > 0.1 for all). ConclusionBased on these results, the medial and lateral locked plating technique demonstrates a higher union rate, with possible lower rates of revision surgery, compared to a single lateral plate in highly comminuted distal femur fractures. Level of evidenceLevel 3. Retrospective Cohort Study.

Fibrosarcoma arising after femur osteosynthesis with pin and plate placement in a cat

A 6-year old spayed female Siamese cat was presented with a history of left limb acute lameness. Radiographic imaging revealed a complete comminuted diaphyseal femur fracture, which was corrected through intramedullary pin placement along with plate osteosynthesis. After two months the animal returned to the hospital presenting severe diffuse enlargement of the left hindlimb, characterized as a non-delimited, solid, and firm plaque-like mass surrounding the pin and bone, which extended from the femorotibiopatelar joint to the pelvis, and infiltrated the adjacent musculature. Incisional biopsy exam indicated a highly malignant sarcoma. The entire limb was surgically removed and sent to histopathological evaluation. Microscopically, the mass was composed of spindle shaped cells, displaying high pleomorphism and cellular atypia. Abundant collagen production was evidenced through Masson's trichrome stain and strong cytoplasmic staining for vimentin. These results were consistent with fibrosarcoma. The cat went through one session of chemotherapy; however, tumor recurrence occurred 20 days later, and the animal was submitted to euthanasia. This is the first description of fibrosarcoma arising in the vicinity of an intramedullary pin and plate in a cat.

P113. Integrated interbody fusion in multilevel cervical constructs in clinical practice

BACKGROUND CONTEXT Although extremely effective at a single level, anterior cervical discectomy and fusion (ACDF) with an anterior cervical plate (ACP) for a multilevel construct can be associated with a number of peri- and postoperative complications. Such complications include esophageal dysphagia, loss of sagittal balance secondary to plate installation, and technical difficulties with the placement of anterior cervical plate over a multiple fusion levels. As an alternative, and quite possibly superior to cervical plating, individual cervical integrated interbody fusions with subsequent compressive/lag fixation, has emerged as a promising alternative. This has the potential to allow for smaller exposure, zero anterior profile, and individual, but multilevel specific sagittal realignment. PURPOSE The purpose of the study was to retrospectively evaluate patients treated from single to multiple levels with integrated interbody fusion by a single surgeon. STUDY DESIGN/SETTING Retrospective patients' data analysis. PATIENT SAMPLE A total of 203 patients with symptomatic cervical degenerative disc disease with radiculopathy and/or myelopathy were surgically treated with a cervical integrated interbody fusion device with compressive fixation between the C3-C7 levels. OUTCOME MEASURES Patients were evaluated for patient-derived outcome measures, and radiographic parameters (effect on device-level lordosis, overall cervical sagittal alignment and fusion status), and device-related complications. METHODS A total of 203 patients with symptomatic cervical degenerative disc disease with radiculopathy and/or myelopathywere surgically treated with a cervical integrated interbody fusion device with compressive fixation between the C3-C7 levels. Patients were assessed pre- and post-operatively at 6 weeks, 3, 6 months, 1 and 2 years. RESULTS The average age at time of surgery was 53.4±10.7 years. All had failed conservative treatment. Seventy-four patients underwent the procedure at single level, 68 patients at 2-levels, 39 patients at 3-levels, and 17 patients at 4-levels, 4 patients at 5-levels and 1 patient at 6-levels. Blood loss was minimal and no intraoperative complications were recorded. Hospital stay was minimal with 92% of patients being released the following day. Radiographic results showed lordosis was maintained in the global spine and bone formation was present in the inner column of the device. Overall fusion rate was 92%. The revision surgery patients showed better alignment than preoperatively with static plates. There were no signs of heterotopic ossification of the ligaments or vertebral bodies. At 6 months, none of the patients reported chronic dysphagia. There were no device failures out to last follow-up. Eighty-six percent of patients were able to return to the same level of work as prior to surgery. CONCLUSIONS For patients undergoing single and multi-level cervical fusion, integrated interbody fusion with compressive/lag fixation appears to be a viable alternative. Previously, studies with static integrated interbody fixation devices have not reported as well as ACP with regards to fusion and clinical outcomes. The benefit of a lag design to provide better fixation and more accurate maintenance of the lordotic curve of the cervical spine was seen in our series. Patients reported they were well satisfied with their results and experienced significant pain relief. The opportunity to either revise a previous ACDF with ACP or add to a pre-existing ACDF offers greater flexibility to treat the pathology at the index level rather than approach as a global construct. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Anatomical study of Lapidus arthrodesis using two different plantar plate systems

BackgroundFirst tarsometatarsal arthrodesis (modified Lapidus procedure) constitutes a sufficient treatment for moderate to severe hallux valgus deformity and first ray instability. The plantar plate arthrodesis was shown to provide superior mechanical stability and less postoperative complications than screw fixation or dorsal plating. Nevertheless, the in-brought hardware may cause irritation of the tibialis anterior or peroneus longus tendon requiring explantation of the material in some cases.The purpose of this study was to investigate the potential of tendon irritation after plantar first tarsometatarsal joint arthrodesis in a cadaver study. MethodsPlantar plate arthrodesis was performed as in real surgery on twelve pairs of fresh frozen cadaveric feet. Two different plate systems were randomly allocated to each pair of feet. After plate fixation careful dissection of the feet followed to analyze potential tendon irritation and to determine a “safe zone” for plantar plate placement. ResultsA “safe zone” between the insertion sties of tibialis anterior and peroneus longus tendon was found and proven to be sufficiently exposed using a standard medio-plantar approach. Both plates were fixed in this zone without compromising central tendon parts. Peripheral tendon parts were irritated in 42% using Darco Plantar Lapidus Plating System® (Wright Medical, Memphis, TN) and in 8% using the Plantar Lapidus Plate® (Arthrex, Naples, FL). Bending of the anatomically preshaped plates is often necessary to ensure optimal fit on the bone surface. ConclusionsModified Lapidus procedure with plantar plating of the first tarsometatarsal joint can be performed safely without compromising central tendon parts via standard medio-plantar approach. Level of clinical evidence5, Cadaver Study.

S4A-12 SESSION 4A: GENERALITIES IN CRANIOSYNOSTOSIS – PART I THE EFFICACY OF OUR NOVEL SUTURECTOMY TECHNIQUE WITH ABSORBABLE PLATES IN EARLY SURGERY FOR CRANIOSYNOSTOSIS

Introduction: Surgical procedures for craniosynostosis patients with severe intracranial hypertension include suturectomy, cranial distraction and conventional cranial reconstruction. Suturectomy has been performed in children younger than 3 months of age with insufficient bone strength. Conventional suturectomy is generally ineffective, because bone formation occurs rapidly in the grooves, resulting in recurrent elevation of intracranial pressure and severe deformity. Therefore, the surgical effects should be extended by preventing bone formation during the early postoperative period to correct the severe deformity and subsequently achieve sufficient bone formation and strength. This study examined the efficacy of our newly developed suturectomy technique using an absorbable plate. We present our novel method and the postoperative follow-up. Methods: Our new method was indicated for craniosynostosis cases younger than 3 months of age who had severe intracranial hypertension, scaphocephaly, or plagiocephaly between 2011 and 2018. All patients underwent suturectomy. Suture lines that indicate premature fusion were incised at a width of approximately 7–10 mm to insert the absorbable plates. The bone stumps on both sides of the grooves were covered with absorbable sheet-type plates. Evaluation was conducted primarily with three-dimensional computed tomography and clinical photographs, and the preoperative and postoperative cephalic index were analyzed. Results: Twenty-three patients who underwent surgery were evaluated. The cranial shape was brachycephaly in five, scaphocephaly in four, oxycephaly in five, clover-leaf deformity in three, and plagiocephaly in four. There were eleven syndromic (1 Crouzon, 4 Apert, 3 Pfeiffer and 3 Saethre-Chotzen syndromes) and twelve non-syndromic patients. The patients’ mean age at the time of surgery was 43.5 days (12 to 76), and the mean follow-up period was 44.2 months (7 months to 7 years). The postoperative cephalic index improved in all patients. Secondary surgery was not required in five of eleven syndromic and in all non-syndromic patients. There were no major complications. Conclusion: Placement of an absorbable plate during strip craniectomy can prevent bone formation during the early postoperative period and promote bone formation after plate absorption. Even in patients who underwent distraction osteogenesis, the planning of the procedure was relatively easy because improvement in cranial shape had been achieved. In particular, some syndromic craniosynostosis patients were able to avoid additional surgery. Also, good outcomes were obtained without adjunctive therapy, such as helmet therapy. The present approach is less invasive and expected to be highly effective.

Cosmetic and Neuroprotective Placement of Custom-Made Ultra-High-Molecular-Weight Polyethylene Cranial Plate (SKULPIO) in Single-Step Surgery: Technical Note and Case Report

Cranioplasty is a common procedure in neurosurgery. However, cosmetic and neuroprotective reconstructions are necessary after cranioplasty. Treatment of patients with a meningioma with bone infiltration requires removal of the tumor-infiltrated bone and subsequent cranioplasty. We report an efficient technique for cosmetic and neuroprotective reconstructions using a custom-made ultra-high-molecular-weight polyethylene cranial plate (SKULPIO, Kyocera Medical, Kyoto, Japan) in a single-step surgery involving tumor removal and skull reconstruction. We present 2 illustrative cases of a 49-year-old female with a right frontal convexity meningioma and 69-year-old male with a bilateral parasagittal atypical meningioma, both involving extensive skull invasion. We preoperatively planned craniotomy size to facilitate the removal of the tumor-infiltrated skull bone using the patients' 3-dimensional cranial models followed by the construction of a custom-made cranial plate. After tumor removal, we drilled out the outer table and the diploe of the cranial edge until the custom-made bone plate accurately fit the bone defect. Finally, the cranial plate was fixed using titanium plates and screws. Postoperative magnetic resonance imaging for each case revealed total meningioma removal and an aesthetically reconstructed skull. Using this technique, precise adjustment of the cranial edge to the plate contributes to a gapless and aesthetic reconstruction. Furthermore, the intact inner table of the skull firmly supports the custom-made bone plate. This technique involving the placement of a custom-made cranial plate during a single-step surgery was found to be efficient for cosmetic and neuroprotective reconstructions.

Clival screw and plate fixation by the transoral approach for the craniovertebral junction: a CT-based feasibility study.

A clivus screw and plate was invented and proved to strengthen the stability of the craniovertebral junction (CVJ). However, it is unclear whether the clivus screw and plate could be placed onto the CVJ by transoral approach. Therefore, the present study aims to evaluate the feasibility of clivus screw and plate placement by transoral approach and investigate its relative anatomic parameters. A total of 80 normal adults (40 males/40 females) with an average age of 60.4 ± 11.6years old were enrolled in this study. All parameters were measured in a supposed maximums mouth-opening status on computed tomography images, where the vertex of lower incisor was defined as Point A. The vertical intersection from Point A to extracranial clivus was defined as Point B, and its distance to the bottom of clivus was measured as B length. Point B was considered as ideal screw entry point. All the cases were divided into three types based on the location of Point B: above the top portion (Type 1), between the top and bottom portion (Type 2), and below the bottom portion (Type 3) of extracranial clivus. The B Length was defined as a minus value if the case belonged to Type 3. The anterior skull base angle, the angles between tangent of extracranial clivus and the lines from Point A to different parts of clivus, and distances between Point A and clivus and C1-3 vertebra were also measured. One in eighty cases (1.2%) belonged to Type 1 with a B Length of 32.12mm. Most cases (61.3%) were Type 2 with a B Length of 8.7mm, while Type 3's was - 9.7mm occupying for 37.5%. Significant statistic differences were found in anterior skull base angle between these three types (128.9°, 122.7° and 118.5° for Type 1, 2 and 3, respectively). The distances from Point A to the top and bottom portion of the clivus and the pharyngeal tubercle were 97.5, 96.0 and 96.8mm, respectively. The angles between the tangent of the clivus and the lines from Point A to the above three structures were 75.7°, 92.3° and 84.0°, respectively. The distances from Point A to the middle point of anterior margin of C1 anterior tubercle, C2 vertebra and C3 vertebra were 79.1, 73.4 and 61.5mm, respectively. The clivus screw and plate placement could be accomplished with optimal screw angle by transoral approach in most of patients. Mandibular splitting would be needed in patients with greater anterior skull angle. These slides can be retrieved under Electronic Supplementary Material.

Cervical Template to Optimize the Plate-to-Disc Distance in Instrumented Anterior Cervical Discectomies and Fusions: Instrumentation Assessment

An increased incidence of adjacent segment degeneration in the cervical spine has been associated with a plate-to-disc distance (PDD) of <5 mm. To introduce a template to size, position, and secure a cervical plate and ensure a 5-mm minimum PDD. A prospective observational study was performed on 50 consecutive patients who had single-level anterior cervical discectomy and fusion (ACDF) using a cervical template. The cervical template was secured into the interbody spacer and assessed for length, PDD, and adequate vertebral body coverage. Holes were drilled through the template, which was then removed for cervical plate placement. Postoperative radiographs were assessed for PDD to adjacent segments, the angle from the vertical axis of the spine, and distance from midline. Neck Disability Index and visual analog scale scores for the neck and arm were obtained preoperatively and at 30-d and 90-d follow-up. Fifty patients underwent single-level ACDFs. The mean angle from the long axis of the spine was 2.4 (0.0-4.4) degrees; mean distance from midline was 1.3 (0.0-2.8) mm; and mean distance from the plate ends to the adjacent segments above was 5.4 (4.6-6.2) mm, and below, 5.1 (4.3-5.8) mm. A cervical template can reliably secure the midline and predetermine the size of the shortest cervical plate for adequately stabilizing the segment for arthrodesis. Use of a template standardizes the process of maximizing the PDD.

Management of Mandibular angle fractures using three-dimensional strut plate: A comparison between transoral and transbuccal approaches

Aim: To compare between transoral and transbuccal approaches in the management of mandibular angle fractures using 3d-strut plates.Materials and methods: Ten patients with unilateral mandibular angle fracture with an age range 18-56 years were included in our study. The patients were divided into two groups based on the approach for the 3d strut plate placement and fixation. Group A included 5 patients undergoing open reduction and internal fixation (ORIF) via transoral approach and group B included 5 patients undergoing ORIF via transbuccal approach. Patients were followed up clinically at 1 week, 1 month and 3 months postoperatively and radiographically at 1 week and 3 months postoperatively.Results: In the transbuccal group patients, extraoral scar evaluation revealed 3 patients (60%) with invisible scar, 2 patients (40%) with barely visible scar after 3 months postoperatively. The mean time of the surgical procedure starting from the first incision till the last suture was 38.4±6.5 minutes for group A and 41.1±5.2 minutes for group B patients. None of the patients in both groups was introduced with malocclusion, facial nerve affection, segmental mobility, wound dehiscence, infections or parathesia during different follow up periods. Radiographic evaluation didn’t reveal any kind of hardware failures in the terms of plate fracturing or screws loosening and there was no statistically significant difference in the mean bone density along the fracture line between both groups.Conclusion: The use of 3d strut plates in angle fractures through transoral or transbuccal approaches resulted in excellent results with no significant difference clinically or radiographically between both approaches. However, The transbuccal approach was our preferred technique due to ease of use, negligible necessity for plate bending and easy placement of the plate in the neutral mid-point region.

Automating a Magnetic 3D Spheroid Model Technology for High-Throughput Screening.

Affordable and physiologically relevant three-dimensional (3D) cell-based assays used in high-throughput screening (HTS) are on the rise in early drug discovery. These technologies have been aided by the recent adaptation of novel microplate treatments and spheroid culturing techniques. One such technology involves the use of nanoparticle (NanoShuttle-PL) labeled cells and custom magnetic drives to assist in cell aggregation to ensure rapid 3D structure formation after the cells have been dispensed into microtiter plates. Transitioning this technology from a low-throughput manual benchtop application, as previously published by our lab, into a robotically enabled format achieves orders of magnitude greater throughput but required the development of specialized support hardware. This effort included in-house development, fabrication, and testing of ancillary devices that assist robotic handing and high-precision placement of microtiter plates into an incubator embedded with magnetic drives. Utilizing a "rapid prototyping" approach facilitated by cloud-based computer-aided design software, we built the necessary components using hobby-grade 3D printers with turnaround times that rival those of traditional manufacturing/development practices at a substantially reduced cost. This approach culminated in a first-in-class HTS-compatible 3D system in which we have coupled 3D bioprinting to a fully automated HTS robotic platform utilizing our novel magnetic incubator shelf assemblies.

Anterior Guided Growth of the Distal Femur for Knee Flexion Contracture: Clinical, Radiographic, and Motion Analysis Results.

Fixed knee flexion deformity is common in children with neuromuscular disorders. Anterior guided growth (AGG) of the distal femur can achieve gradual correction in patients who are skeletally immature. Little outcome data are available on this procedure. This is a retrospective matched cohort study. Forty-two knees (26 patients) underwent AGG surgery at our institution between 2007 and 2017. All patients underwent instrumented 3-dimensional gait analysis (3DGA). A nonsurgical control group of 49 knees (43 patients) was selected that matched for age, severity of preoperative knee contracture, and 3DGA parameters. Clinical, radiographic, and 3DGA outcomes were assessed and compared. Average preoperative knee flexion deformity in AGG group was 13±8 degrees. Following AGG, deformity improved by 8±7 degrees (P<0.001) as measured radiographically and by 7±7 degrees (P<0.001) as measured on physical examination. Average rate of correction was 0.7±0.6 degrees per month or 8±8 degrees per year. The 3DGA parameters such as minimum stance phase knee flexion and knee flexion at initial contact were also significantly improved following AGG. In contrast, flexion deformity as measured radiographically worsened by 3±3 degrees (P=0.002) in the control group. Twelve knees (29%) had failure of correction. Predictors of failure included older age, lower level of function, and greater severity of preoperative deformity. The age at time of surgery and the anteroposterior position of plate fixation relative to the distal femoral physis were associated with rate of correction. In children with neuromuscular disorders, AGG of the distal femur is effective in improving degree of fixed knee flexion deformity as well as objective gait parameters. A significant portion of knees experience inadequate correction. Addressing factors associated with correction failure (ie, age and plate placement) may improve the procedure's success. Level III-case control study.

Bone Material Properties of Human Phalanges Using Vickers Indentation.

ObjectiveTo investigate the microhardness distribution throughout the human hand phalanges using the Vickers method, which can be used to directly evaluate the bone mechanical properties at tissue level and provide an alternative means to investigate bone quality.MethodsThe phalanges bones involved in this study were collected from three healthy donors; fresh‐frozen right limbs were used. The phalanges bones were dissected and cut into 3‐mm thick slices perpendicular to the long axis in the phalanges base, the phalanges shaft, and the phalanges head with a low‐speed saw and then the slices were polished with sandpaper. A microindenter fitted with a Vickers indenter point was used to measure the Vickers hardness in the plantar, dorsal, medial, and lateral sites of cortical bone in metatarsal shaft and trabecular bone in the metatarsal base and head. The indentation load and dwell time was set to 50 g and 12 s for both the cortical and cancellous tissues in this study. For each site or region, five valid values were recorded and averaged as the Vickers hardness for the site or region.ResultsIn total, 96 bone slices were harvested from the base, shaft, and head of the 15 phalanges and 1920 indentations were performed. In general, the Vickers hardness in phalanges was 34.11 ± 7.95 HV. For the 5 phalanges, the 3rd phalanx showed the highest hardness (36.74 ± 7.10 HV), closely followed by the 1st (36.46 ± 5.96 HV) and 2nd (35.28 ± 6.52 HV) phalanx. The hardness in the 4th (31.90 ± 9.15 HV) and 5th (31.19 ± 8.22 HV) phalanx were significantly lower than in the other 3 phalanges. The hardness in the phalanx shaft (38.52 ± 6.67 HV) was significantly higher than that in both the base (30.73 ± 7.46 HV) and head (30.64 ± 6.81 HV) of the phalanx (F = 300.7, P = 0.000); no statistic difference existed between the base and head of the phalanx (P = 0.996). The Vickers hardness in the proximal, middle, and distal phalanx showed statistical difference in Vickers hardness (F = 19.278, P = 0.000). The proximal phalanx showed higher Vickers hardness than the middle phalanx in the 2nd to 5th phalanges (P = 0.002).ConclusionThis study reported on the Vickers hardness distribution of the human phalanges bone and provides the theoretical basis of differences in hardness, which will benefit the placement of plates and screws in orthopaedic surgery and contribute to the research on ideal artificial bones and 3D‐printed orthopaedic implants with inner gradient distribution of hardness.

A new risk to the axillary nerve during percutaneous proximal humeral plate fixation using the Synthes PHILOS aiming system

Percutaneous aiming arms have been developed to minimize injury during placement of submuscular proximal humerus plates. The purpose of this study was to determine the risk of axillary nerve injury during percutaneous proximal humeral plate fixation using the Synthes PHILOSaiming system. By use of 10 fresh-frozen cadavers (20 shoulders), a 3.5-mm locking compression proximal humeral plate was fixated percutaneously to the humerus through a lateral deltoid-splitting approach using the PHILOSaiming guide. Dissection of the axillary nerve was then carried out, and measurementsof its relation to the screw holes in row A through row G of the plate were taken. The lateral acromion-to-axillary nerve distance was also measured. The axillary nerve traversed row D in every shoulder, whereas it crossed over row C in 11 shoulders and both holes in row E in 16 shoulders. The closest distance to the axillary nerve achieved was 4.5 mm, corresponding to the distal (left) screw in row B. A significant negative correlation was found for the distance from the nerve to the closest proximal and distal screws (row B and row G, respectively) in both right shoulders (ρ = -0.797; 95% confidence interval, -0.916 to -0.548) and left shoulders (ρ = -0.615; 95% confidence interval, -0.831 to -0.237). The axillary nerve traverses rows C, D, and E of the proximal humeral plate using the PHILOSaiming system. Importantly, our study is the first to demonstrate that the axillary nerve crosses over row C. Left-sided plate screws also came in closer proximity to the axillary nerve than right-sided plate screws.

Anatomical-positional relationship between the bone structure of the distal radius and flexor pollicis longus tendon using ultrasonography.

In this study, using an ultrasonography, we investigated the positional relationship between the volar bone cortex of distal radius and flexor pollicis longus (FPL) tendon in the distal radius of healthy subjects. The subjects were 32 healthy volunteers (56 wrists) (Age 32.9 ± 8.5, 16 males and 16 females). Their wrists were imaged by an ultrasonography. The distances between the watershed line (WS) and FPL (A), between the distal margin of pronator quadratus (DMPQ) and FPL (B), between the FPL and volar radial bone cortex at the maximum muscle belly of the PQ muscle right below the sliding region of the FPL tendon (C), and between the WS and DMPQ (D) were measured. All these parameters showed a normal distribution. When the correlation among the parameters was investigated, a correlation with an index of the physique, BMI, was noted in A (P < 0.01), B (P < 0.01), and C (P < 0.01), but no correlation was noted only in D (P = 0.59). Our results were suggested that when distal radius fracture is treated with a distal plate placement, the appropriate placement can be achieved by applying about 3mm additional dissection of soft tissue on the volar bone cortex distal to the DMPQ.

Deep peroneal nerve has a potential risk of injury during open-wedge high tibial osteotomy.

To assess the risk of injury to the neurovascular bundle on the interosseous membrane of the leg during drilling for distal screw insertion in open-wedge high tibial osteotomy (OWHTO), and to investigate the possible influence of the method of plate placement on the risk. This retrospective study involved, 55 patients (32 with a TomoFix plate, 23 with a TriS plate) who underwent postoperative CT scanning of the knee following OWHTO between 2009 and 2018. The angle and position of the locking plate, and the direction of screw insertion relative to the interosseous membrane were analysed. All distal screws had a risk of neurovascular injury. In particular, 25 screws at the #4 hole (45%) had an extended insertion trajectory that intersected with the interosseous membrane. The angle of the proximal part of the TomoFix plate was a significant risk factor. In contrast, methods of TriS plate placement showed no statistically significant differences. Extended insertion trajectories of distal screws were likely to intersect with the interosseous membrane with the neurovascular bundle potentially on its surface; thus, drilling for bicortical fixation posed a risk of neurovascular injury. The risk increased as the TomoFix plate was placed more medially, suggesting that bicortical drilling must be performed with the utmost attention when the plate is placed at the medial position. Given the particularly high risk at the #3 and #4 screw holes, monocortical fixation of a few distal screws is recommended as long as good stability is ensured.

Interosseus Wiring of Distal Radius Fractures With Volar Comminution

Interosseous wiring is a technique that has been used for decades to help achieve interfragmentary compression and subsequent osteosynthesis in a number of fracture patterns. Comminuted distal radius fractures with larger volar fragments present challenges for reconstruction and reestablishment of length, rotation, and alignment of the metadiaphyseal region. In many instances, the use of bridge plating in these fracture patterns is difficult as the fragments are prone to displacement. Utilizing interosseous wiring in distal radius fractures with larger volar fragments provides an extraordinarily useful technique, allowing for anatomic reduction and restoration of the articular block. This stabilizing aid provides an ideal reduction for proper placement of a volar locked plate. This study describes the technique of interosseous wiring in a 75-year-old female patient with distal radius and ulnar fractures with subsequent volar locked plate placement. This technique provides an efficient and cost-effective tool to improve anatomic reduction, interfragmentary compression, and proper plate placement in distal radius fractures of this morphology.

Analysis of risk factors for loss of reduction after acromioclavicular joint dislocation treated with the suture-button

BackgroundThe most commonly reported complication after acromioclavicular (AC) joint dislocation treated with the Suture-button is loss of reduction. Loss of reduction is a major factor influencing the patient's joint function and subjective satisfaction. The objective of this study is to analyze the risk factors causing loss of reduction after AC joint dislocation treated with the Suture-button. MethodsOne hundred and thirty patients with AC joint dislocation who were surgically treated the Suture-button in our hospital from February 2009 to February 2015, were recorded their age, sex, BMI, time from injury to surgery, Rockwood's classification, with or without osteoporosis, double or triple button technique, position of the clavicle tunnel, tunnel diameter, coracoid button position, alignment of the button, acromioclavicular ligament repair or not, different methods of postoperative limb immobilization, and so on. Mean comparisons or chi-square test was used for univariate analysis of the above factors, and then multivariate logistic regression analysis was performed to predict risk factors. ResultsReduction was lost in 23.1% of the patients. Univariate analysis showed that button alignment, double or triple button technique, coracoid button position, position of the clavicle tunnel, acromioclavicular ligament repair or not and osteoporosis had statistically significant association with loss of reduction for AC joint (P = 0.031, 0.034, 0.000, 0.042, 0.047 and 0.000 respectively). Multivariate logistic regression analysis demonstrated that osteoporosis (P = 0.003), position of the clavicle tunnel (P = 0.032) and coracoid button position (P < 0.001) were the risk factors that significantly associated with the loss of reduction after AC joint dislocation treated with the Suture-button. ConclusionsClavicle tunnel location using relative ratio method, accurate placement of button plate under coracoid process (inside or outside deviation <20°), various reinforcement operations for patients with osteoporosis are important factors in preventing loss of reduction.

The impact of plate length, fibula integrity and plate placement on tibial shaft fixation stability: a finite element study

BackgroundTibial shaft fractures account for approximately 15% of long bone fractures. Locked plates with minimally invasive plate osteosynthesis techniques are used widely by surgeons. The purpose of this study is to investigate the impact of factors meaning the plate length, fibula integrity, and placement of the plate on the stability of tibial shaft fracture fixation.MethodsA finite element model of the tibial shaft fracture was built. An axial force of 2500 N was applied to simulate the axial compressive load on an adult knee during single-limb stance. The equivalent von Mises stress and displacement of the fractured ends were used as the output measures.ResultsIn models with plates on the lateral side of the tibia, displacement in models fixed with a 12-hole plate showed the smallest value. In models with plates on the medial side of the tibia, displacement in models fixed with 14-hole plate showed the smallest value. The peak stress of plates implanted on the medial side of the tibia was higher than that of plates on the lateral side. The peak stress and the displacement of models involved with the fibula were lower than that of models without fibula, regardless of the length or location of plates.ConclusionsFor models with plates on the medial side of the tibia, the 14-hole plate is the best choice in terms of stability. While for models with plates on the lateral side of the tibia, the 12-hole plate demonstrated the optimal biomechanical stability. The integrity of the fibula improves the anti-vertical compression stability of the construct. The peak stress of plates implanted on the medial side of the tibia was higher than that of plates on the lateral side, which indicated that the construct with medially implanted plate has a higher risk of implant failure.

Spine Stabilization Is a Risk Factor for the Development of Pelvic Iliac Vein Lesions

Open lumbar spine stabilization surgery often requires mobilization of the left and right common iliac veins (CIVs) and the placement of plates and screws that can impinge on iliac veins. We reviewed our venography experience during the past 3 years to determine whether there is an association between spine stabilization surgery and the development of iliac vein lesions and symptomatic iliac vein outflow obstruction. A retrospective chart review was performed to identify patients who underwent venography with or without venous stenting and who had a history of previous lumbar spine stabilization. From January 2014 to April 2018, venography were performed in 1713 limbs in 1245 patients at the Center for Vascular Medicine. Of the 1245 patients, 17 patients had a history of lumbar spine stabilization procedures (4 anterior-posterior and 13 posterior). Nine had single-level and eight had two- or three-level fusions. All 17 patients demonstrated pelvic lesions, which included the following: one left CIV aneurysm, five left CIV stenoses, three bilateral CIV stenoses, two left CIV and inferior vena cava occlusions, and two external iliac vein stenoses. The aneurysm patient was treated with anticoagulation. Eight patients underwent stenting, and one patient refused stenting because of relocation to another country. One inferior vena cava-CIV occlusion could not be crossed. Fear of dislodging a thrombus and the proximity to a protruding posteriorly placed screw prevented stenting in two patients. Four patients had a venoplasty alone because of undersizing of a stenosis or missed lesions with intravascular ultrasound after review by a blinded reviewer. Lesions in anterior-posterior patients were extremely stenotic, required predilation, and resulted in a residual stenosis requiring venoplasty at a second setting in one patient. Lumbar spine stabilization surgery may be a risk factor for development of symptomatic venous outflow obstruction lesions. During venography and stenting in patients with anterior-posterior approaches, significant scarring may be encountered, resulting in a residual stenosis after stent placement. Predilation venoplasty, before stent deployment, is recommended to prevent stent migration. Furthermore, a history of spine stabilization surgery in patients presenting with pelvic or lower extremity pain or swelling should prompt consideration of a pelvic venous duplex ultrasound examination to assess for the presence of an iliac venous outflow lesion.

Parameterization of proximal humerus locking plate impingement with in vitro, in silico, and in vivo techniques

Locked plating of displaced proximal humeral fractures is common, but rates of subacromial impingement remain high. This study used a multidisciplinary approach to elucidate the relationships between common surgical parameters, anatomic variability, and the likelihood of plate impingement. The experiment was completed in 3 phases. First, a controlled in vitro experiment was conducted to simulate impingement. Second, a dynamic in silico musculoskeletal model modeled changes to implant geometry, surgical techniques, and acromial anatomy, where a collision detection algorithm was used to simulate impingement. Finally, in vivo shoulder kinematics were recorded for 9 activities of daily living. Motions that created a high likelihood of impingement were identified. Of simulated impingement events, 73.9% occurred when the plate was moved proximally, and 84% occurred when acromial tilt was 20° or 25°. Simulations of impingement occurred at cross-body adduction angles between 10° and 50°. Impingement occurred at an average of 162.0° ± 14.8° abduction with 10 mm distal plate placement, whereas the average was 72.1° ± 11.4° with 10 mm proximal placement. A patient may encounter these shoulder angles when performing activities such as combing one's hair, lifting an object overhead, and reaching behind one's head. Proximal implant placement and decreases in acromial tilt play major roles in the likelihood of impingement, whereas plate thickness and humeral head center of rotation should also be considered. Careful preoperative planning that includes these factors could help guide operative decision making and improve clinical outcomes.