Biomechanical study of a low-cost external fixator for diaphyseal fractures of long bones.

BACKGROUND: External fixation improves open fracture management in emerging countries. However, sophisticated models are often expensive and unavailable. We assessed the biomechanical properties of a low-cost external fixation system in comparison with the Hoffmann® 3 system, as a reference. METHODS: Transversal, oblique, and comminuted fractures were created in the diaphysis of tibia sawbones. Six external fixators were tested in three modes of loading-axial compression, medio-lateral (ML) bending, and torsion-in order to determine construction stiffness. The fixator construct implies two uniplanar (UUEF1, UUEF2) depending the pin-rods fixation system and two biplanar (UBEF1, UBEF2) designs based on different bar to bar connections. The designed low-cost fixators were compared to a Hoffmann® 3 fixator single rod (H3-SR) and double rod (H3-DR). Twenty-seven constructs were stabilized with UUEF1, UUEF2, and H3-SR (nine constructs each). Nine constructs were stabilized with UBEF1, UBEF2, and H3-DR (three constructs each). RESULTS: UUEF2 was significantly stiffer than H3-SR (p < 0.001) in axial compression for oblique fractures and UUEF1 was significantly stiffer than H3-SR (p = 0.009) in ML bending for transversal fractures. Both UUEFs were significantly stiffer than H3-SR in axial compression and torsion (p < 0.05), and inferior to H3-SR in ML bending, for comminuted fractures. In the same fracture pattern, UBEFs were significantly stiffer than H3-DR (p = 0.001) in axial compression and torsion, while only UBEF1 was significantly stiffer than H3-DR in ML bending (p = 0.013). CONCLUSIONS: The results demonstrated that the stiffness of the UUEF and UBEF device compares to the reference fixator and may be helpful in maintaining fracture reduction. Fatigue testing and clinical assessment must be conducted to ensure that the objective of bone healing is achievable with such low-cost devices.

Cost Variation in Temporizing External Fixation of Tibial Plateau Fractures.

BACKGROUND: Rising health care expenditures and declining reimbursements have generated interest in providing interventions of value. The use of external fixation is a commonly used intermediate procedure for the staged treatment of unstable fractures. External fixator constructs can vary in design and costs based on selected component configuration. The objective of this study was to evaluate cost variation and relationships to injury and noninjury characteristics in temporizing external fixation of tibial plateau fractures. We hypothesize that construct costs are highly variable and present no noticeable patterns with both injury and noninjury characteristics. METHODS: A retrospective review of tibial plateau fractures treated with initial temporizing external fixation between 2010 and 2016 at 2 Level I trauma centers was conducted. Fracture and patient characteristics including age, body mass index, AO/OTA classification, and Schatzker fracture classification were observed with construct cost. In addition, injury-independent characteristics of surgeon education, site of procedure, and date of procedure were evaluated with construct cost. Factors associated with cost variation were assessed using nonparametric comparative and goodness-of-fit regression tests. RESULTS: Two hundred twenty-one patient cases were reviewed. The mean knee spanning fixator construct cost was $4947 (95% confidence interval = $4742-$5152). The overall range in construct costs was from $1848 to $11,568. The mean duration of use was 16.4 days. No strong correlations were noted between construct cost and patient demographics (r = 0.02), fracture characteristics (r = 0.02), or injury-independent characteristics (r = 0.10). Finally, there was no significant difference between constructs of traumatologists and other orthopaedic surgeon subspecialists (P = 0.12). CONCLUSIONS: Temporizing external fixation of tibial plateau is a high-cost intervention per unit of time and exhibits massive variation in the mean cost. This presents an ideal opportunity for cost savings by reducing excessive variation in implant component selection. LEVEL OF EVIDENCE: Level III. Retrospective Cohort.

A practical, quantitative, fracture healing endpoint assessment criterion for tibial fractures treated with external fixation.

There is a need for a quick, simple, repeatable, but quantifiable assessment tool to determine the fracture healing endpoint of tibial fractures that does not rely on the use of X-rays or on un-measured manipulation. This article presents an argument to support a 'maximum of 1° bending' criterion. The criterion was established from an examination of patient fracture stiffness profiles and following observations of stiffness measurements made in clinics. A proprietary mono-lateral external fixator was used to test the criterion. Sixty subjects had their fracture healing endpoint assessed using this criterion compared with the 15 N m/deg in two planes criterion, and it was deemed to be successful. The method of assessment for both mono-lateral and frame fixation (Ilizarov) is demonstrated.

A Novel Inexpensive Technique to Seal Negative Pressure Wound Therapy on External Fixation Devices.

Negative pressure wound therapy, a tool widely applied to treat lower limb traumas, is useful in reconstructive procedures. However, obtaining an airtight vacuum seal when using a negative pressure dressing around an external fixation device can be complicated and time-consuming. The plastic drape seldom adheres to screws, pins, or wires and, as such, the vacuum seal is jeopardized. In surgical departments, colostomy paste is widely used, readily available, and applied where pins and wires make contact with the plastic drape. It is a fast, practical, and inexpensive method of preventing air leakage. In conclusion, to obtain an airtight seal between the skin and an external fixation device, colostomy paste may be used to ensure an optimal tight seal, even for complex and extended wounds, for 3-5 days without complications or the requirement for additional dressing changes. Furthermore, it is inexpensive, readily available, simple to use, and quick to apply.

Fijación dinámica para la patología degenerativa de columna / Dynamic fixation for spine degenerative diseases

CONTEXTO CLÍNICO: Según el proyecto carga global de enfermedad (GBD, del inglés Global Burden of Disease),durante el 2015 el dolor lumbar y cervical fue la primera causa de discapacidad em adultos de 25 a 64 años en la mayoría de los países latinoamericanos entre los que se encuentra la Argentina. Existen diversas causas de lumbalgia.Mientras la mayoría de los pacientes padecen de dolor inespecífico, las causas identificables abarcan desde enfermedades sistémicas serias hasta causas como la hernia de disco o la estenosis espinal. Estas dos últimas,sólo están presentes en 3-4% de los pacientes. La estenosis espinal es en general multifactorial, siendo la espondilolistesis y el engrosamiento del ligamento amarillo las causas más frecuentes que em general afectan a los pacientes mayores de 60 años. Cuando el dolor causado por la estenosis espinal no revierte con tratamiento conservador (analgésicos, antiinflamatorios, inyecciones epidurales de glucocorticoides, terapia física, etc.), el tratamiento de elección es la cirugía. El objetivo del tratamiento quirúrgico es la mejoría de los síntomas, la mejora de la función y la prevención del daño neurológico. Las alternativas quirúrgicas incluyen la laminectomíadescompresiva con o sin fusión espinal (con o sin instrumentación). La cirugía de fusión espinal que suele ser elegida en los casos de espondilolistesis, presenta como efecto adverso alteraciones funcionales en los discos adyacentes (degeneración del segmento adyacente) al verse expuestos a un estrés dinâmico mayor. Se propone a la fijación dinámica posterior como una alternativa a la cirugía de fusión espinal que evitaría la degeneración del segmento adyacente al disminuir la sobrecarga mecânica sobre las porciones de la columna no fijada. TECNOLOGÍA: Los dispositivos para la fijación dinámica posterior de la columna se componen de tornillos que se colocan en el pedículo vertebral y de barras estabilizadoras. Existen dispositivos compuestos por tornillos y barras móviles y otros con tornillos fijos o rígidos. Existen a su vez dos tipos de barras móviles, unas realizadas en material metálico (similar a un resorte) y otras realizadas en policarbonato y polietileno (similar a un cordón). OBJETIVO: Evaluar la evidencia disponible acerca de la eficacia, seguridad y aspectos relacionados a las políticas de cobertura los dispositivos de fijación dinámica para la patología degenerativa de columna. MÉTODOS: Se realizó una búsqueda en las principales bases de datos bibliográficas (incluyendo Medline, Cochrane y CRD), en buscadores genéricos de Internet, agencias de evaluación de tecnologias sanitarias y financiadores de salud. Se priorizó la inclusión de revisiones sistemáticas (RS), ensayos clínicos controlados aleatorizados (ECAs), evaluaciones de tecnologías sanitarias y económicas, guías de práctica clínica (GPC) y políticas de cobertura de diversos sistemas de salud disponibles. RESULTADOS: Para el siguiente informe se incluyeron dos RS, un documento de evaluación de tecnologia sanitaria, una guía de práctica clínica y cuatro políticas de cobertura. CONCLUSIONES: Abundante evidencia de baja calidad sugiere que los sistemas de fijación dinámica son útiles para el tratamiento de la patología degenerativa de la columna que requiere tratamento quirúrgico y que los mismos no son superiores a la cirugía de fusión espinal. Los financiadores privados de Estados Unidos consideran a su uso experimental, mientras que el sistema de salud del Reino Unido contempla su cobertura.

Metaphyseal locking plate as an external fixator for open tibial fracture: Clinical outcomes and biomechanical assessment.

OBJECTIVE: This study aimed to evaluate the outcome of using a metaphyseal locking plate as a definitive external fixator for treating open tibial fractures based on biomechanical experiments and analysis of clinical results. METHODS: A metaphyseal locking plate was used as an external fixator in 54 open tibial fractures in 52 patients. The mean follow-up was 38 months (range, 20-52 months). Moreover, static axial compression and torsional tests were performed to evaluate the strength of the fixation techniques. RESULTS: The average fracture healing time was 34.5 weeks (range, 12-78 weeks). At 4 weeks postoperatively and at the final follow-up, the average Hospital for Special Surgery knee score was 85 (range, 81-100) and 94 (range, 88-100), respectively, and the American Orthopaedic Foot and Ankle Society score was 88 (range, 80-100) and 96 (range, 90-100), respectively. Based on the static test result, the axial stiffness was significantly different among groups (p=0.002), whereas the torsional stiffness showed no significant difference (p=0.068). CONCLUSIONS: Clinical outcomes show that the use of locking plate as a definitive external fixator is an alternative choice for tibial fractures after obtaining appropriate fracture reduction. However, external locked plating constructs were not as strong as standard locked plating constructs. Therefore, the use of external locked plating constructs as a definitive treatment warrants further biomechanical study for construct strength improvement.

Review of Drop Hallux: Assessment and Surgical Repair.

Peroneal nerve palsy is common. The hallmark clinical manifestation of peroneal nerve palsy is drop foot. In the drop foot condition, the ankle cannot flex, and the foot does not clear the ground during the swing phase of gait. Spontaneous nerve repair can yield complete or incomplete resolution of drop foot. Some patients with incomplete resolution are left with a drop hallux condition, in which the ankle can dorsiflex, but the hallux remains unable to dorsiflex. This has not been thoroughly discussed in the past, regarding surgical repair. In the present report, we have reviewed the drop hallux condition and an effective surgical repair option (extensor hallucis longus to tibialis anterior tendon anastomosis). Our case report presents a healthy 27-year-old male who had persistent drop hallux after drop foot resolution, 3 years after external fixation of a closed, proximal tibia-fibula fracture.

Operative Cost Comparison: Plating Versus Intramedullary Fixation for Clavicle Fractures.

Although clavicle fractures often heal well with nonoperative management, current literature has shown improved outcomes with operative intervention for specific fracture patterns in specific patient types. The 2 most common methods of midshaft clavicle fracture fixation are intramedullary and plate devices. Through retrospective analysis, this study performed a direct cost comparison of these 2 types of fixation at a single institution over a 5-year period. Outcome measures included operative costs for initial surgery and any hardware removal surgeries. This study reviewed 154 patients (157 fractures), and of these, 99 had intramedullary fixation and 58 had plate fixation. A total of 80% (79 of 99) of intramedullary devices and 3% (2 of 58) of plates were removed. Average cost for initial intramedullary placement was $2955 (US dollars) less than that for initial plate placement (P<.001); average cost for removal was $1874 less than that for plate removal surgery (P=.2). Average total cost for all intramedullary surgeries was $1392 less than the average cost for all plating surgeries (P<.001). Average cost for all intramedullary surgeries requiring plate placement and removal was $653 less than the average cost for all plating surgeries that involved only placement (P=.04). Intramedullary fixation of clavicle fractures resulted in a statistically significant cost reduction compared with plate fixation, despite the incidence of more frequent removal surgeries. [Orthopedics.2016; 39(5):e877-e882.].

Development and Assessment of a Distal Radial Fracture Model as a Clinical Teaching Tool.

BACKGROUND: Simulation-based learning is increasingly prevalent in the curricula of many surgical training programs. Newly developed simulators must undergo rigorous validity testing before they are used to assess and evaluate surgical trainees. We describe the development of a model that simulates a distal radial fracture requiring closed reduction and cast application and demonstrate its validity. METHODS: We developed a model for simulated treatment of a distal radial fracture with use of a modified Sawbones forearm. Ten junior and ten senior orthopaedic residents were videotaped performing a closed reduction and applying a cast on the model. After each procedure, standard anteroposterior and lateral radiographs of the forearm model were obtained. Two blinded orthopaedic surgeons then rated each resident using a task-specific checklist (Objective Structured Assessment of Technical Skills [OSATS]) and a global rating scale (GRS) as well as radiographic measurements of palmar tilt and three-point index. RESULTS: Compared with the junior residents, senior residents had significantly higher OSATS (p < 0.001) and GRS scores (p < 0.001). The groups did not differ significantly with respect to radiographic palmar tilt (p = 0.86) and three-point index (p = 0.43). All residents were able to restore anatomical alignment, with a mean palmar tilt of 9.1°. In addition, the mean three-point index of all residents was acceptable (0.76). There was a strong correlation between OSATS and GRS scores (r > 0.87; p < 0.01). The inter-rater reliability was high (≥ 0.79) for the OSATS, GRS, and radiographic measurements. CONCLUSIONS: We developed an educational model that simulates a distal radial fracture requiring closed reduction and cast application. We demonstrated construct validity, as the GRS and OSATS tools were able to differentiate senior from junior residents. We were unable to differentiate trainees using radiographic assessment, as all residents restored anatomical alignment and had comparable three-point index scores.

Uniplanar Versus Taylor Spatial Frame External Fixation For Pediatric Diaphyseal Tibia Fractures: A Comparison of Cost and Complications.

BACKGROUND: The purpose of this study was to compare the outcomes and cost variations between uniplanar (UNI) and Taylor Spatial Frame (TSF) external fixation for unstable pediatric tibial diaphyseal fractures. METHODS: We performed an IRB approved, retrospective review of 44 diaphyseal tibial fractures in 42 children treated with external fixation (16 TSF and 28 UNI) between 2003 and 2011, at a single level 1 pediatric trauma center. Data on demographic, clinical, radiographic, treatment cost, and complication differences were analyzed between the 2 groups. The Student t tests, Fisher's exact tests, χ trend tests, logistic regression, and a cost analysis comparison was used to assess the differences. RESULTS: The mean age in both groups was 13 years (range: 6 to 18 y TSF, 9 to 17 y UNI). The mean follow-up was 8 months (TSF) and 13 months (UNI). According to the AO classification, there were 28 type A, 13 type B, and 3 type C fractures with no significant difference between the 2 groups (P=0.69). Total time in the fixator was not different between the 2 groups (UNI 14 wk, TSF 12 wk, P=0.10), but time to union was less in the TSF group (UNI 16 wk, TSF 13 wk, P<0.01). There were no differences in the final radiographic alignment between the groups. The UNI group experienced more complications (7 pin-site infections and 9 reoperations) compared with 4 pin-site infections and 2 reoperations in the TSF group. A cost analysis revealed significant differences in equipment cost (UNI frame=$5074 vs. TSF frame=$10,675; P<0.0001); however, after corrected cost analysis with calculated return to the operating room for complications, there was no difference in cost of treatment (UNI treatment=$20,113 vs. TSF treatment=$19,138). CONCLUSIONS: Despite an initial equipment cost difference between UNI and TSF frames, corrected cost analysis reveals equivalent costs for care delivery. Therefore, TSF can be considered as a cost-conscious device for the treatment of unstable pediatric tibial diaphyseal fractures. LEVEL OF EVIDENCE: Level III-retrospective comparative cohort study.

External fixation design evolution enhances biomechanical frame performance.

BACKGROUND: External fixation has become a quick and easy application for fracture stabilisation of the extremities and/or pelvis to maintain the reduction and provide stability while sparing the soft tissues. Over the last years, enhanced construct stiffness has become an essential requirement to preserve fracture reduction, particularly in active and overweight patients. This study was performed to determine whether the advancement of design features enhances the external fixation construct stiffness. The stiffness of the recently developed Hoffmann 3 external fixation system was determined and its characteristics compared with the widely clinically accepted Hoffmann II MRI fixation system. METHODS: A synthetic fracture model was used. Two carbon tubes with a fracture gap of 20 mm were appropriate to determine the stiffness of three different configurations: the basic frame configuration (group H 3, representing Hoffmann 3 with a rod diameter of 11 mm) using a double rod construction with 6 mm Apex pins, was compared with the Hoffmann II MRI fixation system using two 8.0 mm diameter rods with 6 mm (group H II-6 mm) and 5 mm (group H II-5 mm) Apex pins. Each group was tested five times under anterior-posterior bending (N/mm), medio-lateral bending (N/mm) and axial torsion loading directions (Nm/deg). The stiffness results of each construct were compared statistically. RESULTS: The basic frame construct (group H 3) showed consistently higher stiffness properties compared with the other configurations. The anterior-posterior-bending loads resulted in a mean value of 31 N/mm, which was significantly higher compared with the other groups (p=0.008) at 16 N/mm. The medio-lateral-bending test revealed a mean stiffness of 59 N/mm in the H3 group, compared with 43 N/mm in the H II-6 group and 31 N/mm in the H II-5 group. The axial torsion measurements of the Hoffmann 3 group yielded significantly higher results (1.03 Nm/°) compared with group H II-6 (0.61 Nm/°) and group H II-5 (0.56 Nm/°). CONCLUSIONS: The Hoffmann 3 construct showed the highest stiffness properties under bending and torsion loads. The enhanced stiffness of the Hoffmann 3 device may be helpful in maintaining fracture reduction and soft tissue compromise. This investigation showed the advancement of Hoffmann design features may be effective in enhancing frame stiffness.

Comparison of Outcomes and Costs of Tension-Band and Locking-Plate Osteosynthesis in Transverse Olecranon Fractures: A Matched-Cohort Study.

To determine if there are significant differences in outcomes and costs between tension-band and locking-plate fixation of transverse olecranon fractures in adults, we retrospectively compared functional outcomes, complications, and costs in 2 cohorts of displaced transverse olecranon fractures. These cohorts (10 patients each) were matched on age and length of follow-up. There were no significant differences between the groups in range of motion, functional scores, or arthrosis. There were no infections or nonunions in either group. There was no significant difference in rate of implant removal or symptomatic implants, though a trend was found toward a higher rate of both with tension bands. Operative time was significantly (P = .025) less for tension-band than locking-plate fixation (55 vs 85 minutes). In the tension-band group, charges were significantly less for implant, index procedure, and overall operative charges including reoperations ($6598.36 vs $14,333.46; P = .001). If all tension bands and no locking plates had been removed, tension-band fixation still would have cost significantly less ($7307.31 vs $14,160.26; P = .0005).

Damage control orthopaedics: Variability of construct design for external fixation of the lower extremity and implications on cost.

INTRODUCTION: To evaluate relative cost of external fixator constructs applied for damage control purposes in a cohort of advanced orthopaedic trainees and orthopaedic staff traumatologists. We also sought to evaluate physicians' understanding of component cost. MATERIALS AND METHODS: Participants were asked to apply an external fixator for three separate fracture patterns in damage control fashion. A total of 19 physicians (nine PGY-4 residents, five PGY-5 residents, two orthopaedic trauma fellows and three orthopaedic staff traumatologists) participated. Total construct cost was calculated. Participants provided an estimate of the cost of each component in a fill-in format survey. Main outcome measures included cost of external fixator construct applied and the estimated cost of external fixator components. RESULTS: Average whole sale cost of an external fixator construct was $5252 (±$1798). Of the three fracture types examined, the tibial plafond fracture external fixator construct on average cost the most, followed by the tibial plateau fracture and the femur fracture construct. The large ex-fix combination clamp was the major contributor to cost for each construct. The combination clamp may be substituted for a multi-pin clamp, resulting in significant cost savings. The self-drilling Schanz pin and the large ex-fix combination clamp were most highly underestimated (25% and 22% of their actual cost, respectively). CONCLUSION: Innumerous construct designs exist and even small changes can significantly impact cost. Knowledge of component cost is low among staff and trainees. Education of component cost is vital to allow adequate consideration of construct design prior to fixator application.

A Pre-fabricated Bracing System for the Management of Humeral Shaft Fractures: Experience of a Centre in the United Kingdom.

BACKGROUND: The aim of our study is to evaluate the ability of a pre- fabricated humeral bracing system in providing sufficient stability to fracture union and carry out a cost analysis comparing bracing versus surgical fixation for these fractures. MATERIAL AND METHODS: A review of humeral shaft fractures treated with a pre-fabricated humeral bracing system was undertaken. RESULTS: 20 humeral fractures (20 patients) were included. Mean patient age was 56.8 years (range 16- 89). There were 14 AO type A, 3 type B and 3 type C fractures. Median time interval from fracture to brace application was 8 days (range 0-41). Clinical and radiological union was achieved in 15 humeri (75%). Median time to clinical and radiological union was 80 days (range 32-434). The cost of treating humeral shaft fractures surgically by plating and by humeral bracing was estimated at £ 2292.99 and £ 1228 per case, respectively. CONCLUSIONS: 1. A pre-fabricated bracing system is an efficacious and cost-effective modality for humeral shaft fracture treatment. 2. It may, however, lead to a high non-union rate as well as shoulder and elbow stiffness. 3. A prospective randomized trial comparing bracing with internal fixation of humeral shaft fractures is needed.

Evidence into practice: pediatric orthopaedic surgeon use of removable splints for common pediatric fractures.

OBJECTIVES: Removable splints when compared with circumferential casts in randomized trials have been shown to be a safe and cost-effective method of managing many common minor distal radius and fibular fractures. This study estimated the extent to which this evidence is being implemented in clinical practice, and determined the perceived barriers to the adoption of this evidence. METHODS: A cross-sectional survey of practicing orthopaedic surgeon members of the Pediatric Orthopedic Surgeons of North America (POSNA) was conducted, using a 22-item online questionnaire, and distributed using a modified Dillman technique. Survey questions were derived from and validated by literature review, expert opinion, and pilot-testing on the targeted sample before implementation. RESULTS: Of the 826 eligible participants, 558 (67.6%) responded to the survey. Of these, 505 (90.5%) had completed a fellowship in pediatric orthopaedics, 335 (60.0%) worked in a university-affiliated setting, and 377 (67.6%) had been in practice for <20 years. Only 158/543 [29.1%; 95% confidence interval (CI), 25.28, 32.92] reported using a removable splint to treat buckle fractures of the distal radius; 32 (5.9%; 95% CI, 3.9, 7.9) and 8 (1.5%; 95% CI, 0.5, 2.5) would use such splints for minimally displaced greenstick and transverse fractures of the distal radius, respectively. For distal fibular avulsion fractures, 122 (22.5%; 95% CI, 19.0, 26.0) would use a removable splint; 57 (10.5%; 95% CI, 7.9, 13.1) and 28 (5.6%; 95% CI, 3.7, 7.5) would do so for nondisplaced Salter-Harris I and II fractures of the distal fibula, respectively. The most commonly reported perceived barriers to application of a removable device were concerns about patient compliance, potential complications, and possible medicolegal implications. CONCLUSIONS: Only a relatively small proportion of practicing POSNA use such splints for minor distal radius and distal fibular fractures. These data support the need for implementation of knowledge translation strategies (eg, education) targeted at all the stakeholders to encourage pediatric orthopaedic surgeons to change practice in keeping with the best evidence for these common and stable injuries. LEVEL OF EVIDENCE: Level II.

The treatment of stable paediatric forearm fractures using a cast that may be removed at home: comparison with traditional management in a randomised controlled trial.

We investigated whether, in the management of stable paediatric fractures of the forearm, flexible casts that can be removed at home are as clinically effective, cost-effective and acceptable to both patient and parent as management using a cast conventionally removed in hospital. A single-centre randomised controlled trial was performed on 317 children with a mean age of 9.3 years (2 to 16). No significant differences were seen in the change in Childhood Health Assessment Questionnaire index score (p = 0.10) or EuroQol 5-Dimensions domain scores between the two groups one week after removal of the cast or the absolute scores at six months. There was a significantly lower overall median treatment cost in the group whose casts were removed at home (£150.88 (sem 1.90) vs £251.62 (sem 2.68); p < 0.001). No difference was seen in satisfaction between the two groups (p = 0.48).

Assessment of the adequacy of closed reduction in fractures of the zygomatic arch using "C"-arm image intensifier.

Major problems in closed reduction of isolated, minimally displaced, and depressed zygomatic arch fractures are blind nature of the technique, reliability on digital palpation, reduction click, and step deformity between fragments. The purpose of this study was to objectively confirm the adequacy of closed reduction intraoperatively and the usefulness of the "C"-arm image intensifier. A total of 12 patients with 1- to 8-day-old unilateral isolated and depressed zygomatic arch fracture underwent closed reduction under "C"-arm image intensifier. Of these patients, 9 were men and 3 were women, with age ranging from 18 to 32 years. Intraoperative prereduction and postreduction images were obtained using the "C"-arm image intensifier. Criteria for adequate reduction were the following: intrafragmentary gap less than 0.5 mm, no overriding of fragments, no depression of fragments, and no step deformity. After being clinically satisfied about the reduction, images on "C"-arm showed no intrafragmentary gap. In 3 patients, there were residual overriding and minimal rotation around the anteroposterior axis of the posterior fragment. In 1 patient, rotation and step deformity remained. In this patient, additional stabilization was provided. The "C"-arm image intensifier shows some poorly reduced or unstable isolated depressed zygomatic arch fractures that remain unidentified even after careful palpation. Thus, it plays a recognizable role to avoid the trouble of second intervention.

Accuracy of pedicle screw placement in the lumbosacral spine using conventional technique: computed tomography postoperative assessment in 102 consecutive patients.

OBJECT: The goal of this study was to determine the incidence of screw misplacement and complications in a group of 102 patients who underwent transpedicle screw fixation in the lumbosacral spine with conventional open technique and intraoperative fluoroscopy. The results are compared with published data. METHODS: Cases involving 102 consecutive patients (424 inserted screws) were reviewed. Surgery was performed in all cases by the same surgeon's team, using the same implant, and all results were assessed by means of a specific CT protocol. The screw position was assessed by the authors and an independent observer. Screw position was classified as correct when the screw was completely surrounded by the pedicle cortex, as "cortical encroachment" (questionable violation) if the pedicle cortex could not be visualized, and as "frank penetration" when the screw was outside the pedicular boundaries. Frank penetration was further subdivided as minor (when the edge of the screw thread was up to 2.0 mm outside the pedicle cortex), moderate (2.1-4 mm), and severe (> 4 mm). The incidence of intra- and postoperative complications not related to screw position as well as hardware failures were also registered, with a minimum follow-up duration of 8 months. RESULTS: The rate of frank pedicle screw misplacement was 5%. The rate of minimal or questionable pedicle wall violation was 2.8%. Among the frank misplacements, 6 were classified as minor, 12 as moderate, and 3 as severe penetration. Two patients (2%) had radicular pain and neurological deficits (inferomedial and inferolateral minor misplacement at L-4 and L-5, respectively), and 5 patients (4.9%) complained only of radicular pain. At the follow-up examination all patients had completely recovered their neurological function and radicular pain was resolved in all cases. The complications not related to screw malposition were 2 pedicle fractures (2% of patients), 1 nerve root injury (1%), and 1 dural laceration (1%). Five patients (4.8%) had postoperative anemia and required transfusions. Superficial or deep wound infection was noted in 3 patients (2.9%). Late hardware failure occurred in 2 patients (2%). One patient developed adjacent segmental instability and required additional surgery to extend the fusion. CONCLUSIONS: Our rates of screw misplacement and complications compare favorably with the lowest rates of the series in which conventional technique was used and are close to the rates reported for image-guided methods. The risk of malpositioning may be reduced with careful preoperative surgical planning, accurate knowledge of the spinal anatomy, surgical experience, and correct indication for conventional surgery. The conventional technique still remains a practical, safe, and effective surgical method for lumbosacral fixation.