Arbeitsgemeinschaft Für Osteosynthesefragen/Association For The Study Of Internal Fixation Research Articles

Surgical Treatment of Intracapsular Condylar Head Fracture with Lag Screw Technique. A Case Report

Intracapsular condylar fractures may account for 65% of all condylar fractures. This diversity of classifications makes epidemiological data collection challenging. Historically, intracapsular condylar fractures were treated in a closed or conservative manner, without open surgery and fixation of the bone fragments. Closed treatment has been described with acceptable outcomes without the risk of complications associated with the surgical treatment, that is, infection, damage to the facial nerve, and unaesthetic extra-oral scar. Recently, studies reporting the surgical treatment of condylar head fractures have reported better results regarding mandibular functional aspects, dental, and aesthetic results. It is also suggested that the repositioning of the articular disc during the surgical procedure, could prevent the consequences of its displacement in possible temporomandibular joint dysfunctions. The objective of this study is to report a clinical case of intracapsular condylar head fracture with open treatment, using lag screw fixation according to AO/ASSIF (Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation) protocols and recommendations.

Coronal Imaging Changes Associated with Recollapse of Injured Vertebrae After Percutaneous Vertebroplasty or Percutaneous Kyphoplasty Treatment for Osteoporotic Thoracolumbar Fracture

To observe coronal imaging changes associated with recollapse of injured vertebrae after percutaneous vertebroplasty or percutaneous kyphoplasty for osteoporotic thoracolumbar fracture (OTLF). Fifty-four cases were retrospectively divided into 2 groups according to the Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF) classification of thoracolumbar fracture: group A, type A1 fracture (n= 26); group B, type A3.1 fracture (n= 28). Visual analog scale, Oswestry Disability Index, local scoliotic Cobb angle, and coronal wedge angle of the injured vertebrae were observed preoperatively, on postoperative day 3, and at final follow-up. The average follow-up time was 19.17 ± 6.30 months. At final follow-up, the visual analog scale score and the Oswestry Disability Index score were significantly greater in group B than in group A (both P < 0.05). At final follow-up, loss of correction of scoliotic Cobb angle and coronal wedge angle was significantly higher in group B than in group A (P < 0.05). Percutaneous vertebroplasty or percutaneous kyphoplasty was effective in both type A1 and type A3.1 OTLF. However, coronal imaging changes after percutaneous vertebroplasty or percutaneous kyphoplasty were more obvious in type A3.1 OTLF than in type A1. Moreover, clinical outcomes in type A3.1 OTLF were slightly inferior to those in type A1.

Classification of Orbital Fractures Using the AO/ASIF System in a Population Surveillance Cohort of Traumatic Optic Neuropathy

Purpose: In our prospective nationwide surveillance study of traumatic optic neuropathy (TON) in the United Kingdom, the prevalence of orbital fractures was found to be 39% (47/121). The prevalence of skull fractures was 7.4% (9/121). This study aims to identify the association of craniofacial-orbital fractures with the severity of visual loss.Methods: TON patients who sustained orbital fractures were identified prospectively by population-based active surveillance through the British Ophthalmic Surveillance Unit over a 2-year period. Available CT scans were classified by a head and neck radiologist according to the Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF) scheme: the face was divided into 4 units; fractures in each unit were graded according to displacement (A–C) and severity (1.1–3.3). Correlation between severity of craniofacial orbital fractures and visual acuity as well as number of fractured units and visual acuity were evaluated.Results: Twelve of the 25 patients (48%) with imaging available had adequate high resolution craniofacial CT imaging for review and classification using the AO/ASIF system (i.e. 48 classifiable units). Three of 48 (6%) units were undisplaced (grade A), 18 of 48 (29%) units were minimally displaced (grade B), and 4 of 48 (8%) units had largely displaced (grade C) fractures. Twenty-three units (47.9%) had no fractures; 5 patients had radiological evidence of optic canal fractures. Poor visual acuities positively correlated with severity of fractures graded using the AO/ASIF classification (Spearman’s rho = 0.95, p = 0.05) and number of fractured units (Spearman’s rho = 1.0, p < 0.0001).Conclusion: AO/ASIF classification system provides a uniform method in the assessment of orbital fractures which correlates with visual outcome in TON.

Comparison of lateral and posterior surgical approach in management of extra-articular distal humeral shaft fractures

ObjectiveThe objective of this study was to compare treatment results and complication rates between lateral and posterior approaches in surgical treatment of extra-articular distal humeral shaft fractures. Material and methodsBetween June 2008 and May 2012, a total of 68 patients with extra-articular distal humeral shaft fractures were treated by lateral and posterior approaches. Of the patients, 30 were operated by a lateral approach (group I) and 26 patients were operated by a posterior approach (group II). There was no statistical significance between the two groups in sex distribution, age, the mechanism of the injury, injured arms, AO/ASIF (Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation) classification, and the time from injury to surgery (P>0.05). Operation time, intraoperative bleeding volume, hospitalisation, clinical outcomes, and complications were compared between the two groups. The elbow functional results were evaluated by the Mayo Elbow Performance Score (MEPS). ResultsAll patients were followed up. The average of follow-up in group I was 15.53±2.636 months (range, 12–22 months), and was 16.12±2.889 months (range, 12–22 months) in group II. There was no significant difference in the operation time, intraoperative bleeding time, and hospitalisation between the two groups (P>0.05). In group I, the mean time of bone union was 12.87±1.852 weeks (range, 10–16 weeks), the mean degrees of elbow flexion was 139.20°±3.274° (range, 134–146°), the mean degrees of elbow extension was 4.77°±1.906° (range, 0–8°), and the mean points of MEPS was 87.00±7.724 (range, 70–100 points). In group II, the mean time of bone union was 12.96±2.218 weeks (range, 10–16 weeks), the mean degrees of elbow flexion was 137.85°±4.076° (range, 130–145°), the mean degrees of elbow extension was 5.15°±2.327° (range, 0–9°), and the mean points of MEPS was 86.15±7.656 (range, 70–100 points). There was no significant difference in the bone union, range of elbow flexion, range of elbow extension and MEPS between the two groups (P>0.05). The overall complication rate in group I was lower than that in group II (P=0.041). ConclusionsBoth lateral and posterior surgical approaches acquired satisfied treatment results in the management of extra-articular distal humeral shaft fractures, and there was a lower complication rate using the lateral approach.

Integration of fluoroscopy-based guidance in orthopaedic trauma surgery – A prospective cohort study

IntroductionComputer-assisted guidance systems are not used frequently for musculoskeletal injuries unless there are potential advantages. We investigated a novel fluoroscopy-based image guidance system in orthopaedic trauma surgery. Materials and methodsThe study was a prospective, not randomised, single-centre case series at a level I trauma centre. A total of 45 patients with 46 injuries (foot 12, shoulder 10, long bones seven, hand and wrist seven, ankle seven and spine and pelvis four) were included. Different surgical procedures were examined following the basic principles of the Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF). Main outcome measurements were the number of trials for implant placement, total surgery time, usability via user questionnaire and system failure rate. ResultsIn all cases, the trajectory function was used, inserting a total of 56 guided implants. The system failed when used in pelvic and spinal injuries, resulting in a total failure rate of 6.5% (n=3) of all included cases. The overall usability was rated as good, scoring 84.3%. ConclusionThe novel image-guidance system could be integrated into the surgical workflow and was used successfully in orthopaedic trauma surgery. Expected advantages should be explored in randomised studies.

Surgical treatment of open pilon fractures

To discuss the methods, timing and clinical outcomes of surgical treatment for open pilon fractures. From April 2003 to July 2008, 28 patients with open pilon fractures were treated. All had type C fractures according to the Arbeitsgemeinschaft für osteosynthesefragen-Association for the Study of Internal Fixation (AO/ASIF) classification. Three operative methods were applied, the methods being determined by the types of fracture, soft tissue damage and time interval after injury. Seven cases were treated by debridement and internal fixation with plate; 19 by limited internal fixation combined with external fixation; and 2 by delayed surgery. The clinical outcomes were evaluated by the Burwell-Charnley score. All cases were followed up for from 6 to 48 months (average 24 months). The Burwell-Charnley score of clinical outcomes: anatomic reduction achieved in 12 cases, functional reduction in 15, and unsatisfactory reduction in 1. The healing time was from 2.5 to 11 months (average 4.7 months). Two cases had delayed union. According to the American Orthopaedic Foot and Ankle Society (AOFAS) scale for the ankle joint, there were excellent results in 8 cases, good in 14, fair in 5 and poor in 1. Complications included four cases of skin superficial sloughing, two of superficial infection, one of deep infection, two of delayed fracture union and ten of post-traumatic arthritis. It is important to perform appropriate surgeries for open pilon fracture according to fracture classification, different damage to skin and tissue and time interval after injury. Thorough debridement, proper use of anti-infective medication, appropriate bone grafting, and postoperative ankle function exercise can reduce the occurrence of complications.

Are classifications of proximal radius fractures reproducible?

BackgroundFractures of the proximal radius need to be classified in an appropriate and reproducible manner. The aim of this study was to assess the reliability of the three most widely used classification systems.MethodsElbow radiographs images of patients with proximal radius fractures were classified according to Mason, Morrey, and Arbeitsgemeinschaft für osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF) classifications by four observers with different experience with this subject to assess their intra- and inter-observer agreement. Each observer analyzed the images on three different occasions on a computer with numerical sequence randomly altered.ResultsWe found that intra-observer agreement of Mason and Morrey classifications were satisfactory (κ = 0.582 and 0.554, respectively), while the AO/ASIF classification had poor intra-observer agreement (κ = 0.483). Inter-observer agreement was higher in the Mason (κ = 0.429-0.560) and Morrey (κ = 0.319-0.487) classifications than in the AO/ASIF classification (κ = 0.250-0.478), which showed poor reliability.ConclusionInter- and intra-observer agreement of the Mason and Morey classifications showed overall satisfactory reliability when compared to the AO/ASIF system. The Mason classification is the most reliable system.

Are distal radius fracture classifications reproducible? Intra and interobserver agreement

Various classification systems have been proposed for fractures of the distal radius, but the reliability of these classifications is seldom addressed. For a fracture classification to be useful, it must provide prognostic significance, interobserver reliability and intraobserver reproducibility. The aim here was to evaluate the intraobserver and interobserver agreement of distal radius fracture classifications. This was a validation study on interobserver and intraobserver reliability. It was developed in the Department of Orthopedics and Traumatology, Universidade Federal de São Paulo - Escola Paulista de Medicina. X-rays from 98 cases of displaced distal radius fracture were evaluated by five observers: one third-year orthopedic resident (R3), one sixth-year undergraduate medical student (UG6), one radiologist physician (XRP), one orthopedic trauma specialist (OT) and one orthopedic hand surgery specialist (OHS). The radiographs were classified on three different occasions (times T1, T2 and T3) using the Universal (Cooney), Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF), Frykman and Fernández classifications. The kappa coefficient (kappa) was applied to assess the degree of agreement. Among the three occasions, the highest mean intraobserver k was observed in the Universal classification (0.61), followed by Fernández (0.59), Frykman (0.55) and AO/ASIF (0.49). The interobserver agreement was unsatisfactory in all classifications. The Fernández classification showed the best agreement (0.44) and the worst was the Frykman classification (0.26). The low agreement levels observed in this study suggest that there is still no classification method with high reproducibility.

A comprehensive classification of craniofacial fractures: postmortem and clinical studies with two- and three-dimensional computed tomography

A comprehensive classification of midfacial/craniofacial fractures, based on two- and three-dimensional computed tomography (2D and 3D-CT) is presented. We performed a postmortem analysis of 24 patients who had died from trauma with signs of craniofacial fractures, based on 2D and 3D-CT studies with pathoanatomical findings. In addition, CT findings for 100 patients with craniofacial injuries requiring an emergency CT were correlated with surgical findings and follow-up results. On the basis of the analysis of a total of 377 fractures a classification system is proposed. The system is based on the use of the AO/ASIF (Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation) scheme, defining three types (A, B, C), three groups within each type (e.g. A1, A2, A3) and three subgroups within each group (e.g. A1.1, A1.2, A1.3) with increasing severity from A1.1 (lowest) to C3.3 (highest). The craniofacial region is divided into three units: the lower midface (I), the upper midface (II) and the craniobasal-facial unit (III). Lateral and central fractures are also distinguished. Type A fractures are non-displaced fractures, type B are displaced fractures and type C are complex/defect fractures. Groups A1, B1 and C1 comprise fractures of an isolated unit; groups A2, B2 and C2, combined fractures without involvement of the skull base; and groups A3, B3 and C3 are those combined fractures with involvement of the skull base. A correlation between the severity of the fracture and (i) the number of posttraumatic functional limitations (Spearman rank test, correlation coefficient r=0.42), (ii) the need for bone grafting or dural plastic ( r=0.39) and (iii) facial asymmetry ( r=0.37), was observed. The proposed classification system allows standardised documentation of midfacial and craniofacial fractures, including those not precisely defined by the Le Fort classification scheme.

Open reduction and internal fixation of the distal humerus: functional outcome in the elderly.

To examine the functional outcome of a cohort of elderly patients after open reduction and internal plate and screw fixation of distal humerus fractures. Retrospective review of a consecutive series of patients older than 60 years of age who underwent plate and screw fixation of a distal humerus fracture. Eighteen patients, aged 63 to 85 years (average, 71 years), underwent open reduction and internal fixation of a displaced distal humerus fracture using plates and screws. Three were Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF) type A, 2 were type B, and 13 were type C fractures. The patients were reviewed at a minimum follow-up of 1 year after surgery. All patients had a good or excellent clinical result using a standardized method of evaluation. General health status, as measured by the SF-36 Health Survey, was comparable to the published norms for U.S. male and female populations of similar age. Open reduction and internal fixation of the distal humerus in the elderly can provide good clinical results. Good clinical results, however, do not imply good general health status.

Intraarticular Fractures of the Distal Humerus

In a 12-year period, 104 patients with intraarticular fractures of the distal humerus received surgical treatment. Based on the Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF) classification, there were 40 monocondylar fractures, 46 bicondylar fractures, and 18 fractures of the ulnar epicondyle with the fragment dislocated in the elbow joint. In children almost all fixations were done with Kirschner wires. The adult fractures were stabilized according to the recommendations of the AO/ASIF, i.e., monocondylar fractures by screws and/or single-plate fixation and bicondylar fractures by screws and dual-plate fixation, preferably with reconstruction plates. Comminuted fractures required an additional osteotomy of the olecranon. Except for children, the essential feature of postoperative management was early functional treatment by continuous passive motion. Eighty-eight patients (84.6%) were followed with an average follow-up time of 4.4 years. The results were evaluated for range of motion, pain, working capacity, neural and vascular impairment, valgus/varus deformity, and subjective judgment. The long-term outcome of almost 81% good and very good results suggests that operative treatment can be valuable when indications, anatomic surgical reconstruction, and postoperative care are performed correctly.

Primary mandibular reconstruction using the AO reconstruction plate.

Primary reconstruction of segmental defects of the mandible following cancer resection remains a major problem. In 1976, a stainless steel plate was developed by AO/ASIF (Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation) for mandibular reconstruction. This plate completely stabilizes both mandibular stumps without the need for intermaxillary or external fixation. In addition, when bone grafting is performed, the design of this plate promotes revascularization by allowing maximal contact between grafted cancellous bone and surrounding soft tissue. Since April 1985, we have used this reconstruction plate in six patients undergoing composite resection. The technique did not compromise cancer resection, excessively prolong operating time, or alter postoperative management. All six patients have retained the AO reconstruction plate and have been reconstructed successfully with achievement of satisfactory function and cosmesis.

Stress analysis of a partially slotted intramedullary nail.

A finite element analysis of the Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF) intramedullary femoral nail was performed to study the failure of the nail from circumferential cracking near the slot tip. These failures are evidently the result of a stress-concentrating effect owing to the partially slotted nail design. Several finite element models were created of the proximal one-fourth of the nail. One model of the nail incorporated the cloverleaf profile as it is presently manufactured, and one had a circular cross section. An additional three models were created with alternative slot-tip geometries: a narrowed slot, a tapered slot, and a widened slot. Antero-posterior (AP) and medio-lateral (ML) bending loads and torsion loads were applied in two fundamentally different loading modes: (1) loads that were applied on both sides of the slot tip (spanned); and (2) loads that were self-equilibrating distal to the slot tip (non-spanned). For the load cases studied, for all models, the stresses predicted from the finite element models were locally highest at the junction between the open and closed cross sections. Alternative slot-tip shapes had a marked effect on the predicted stresses, in one case reducing maximum stress by 40%. However, no alternative slot tip shape was uniformly superior for all load cases. Therefore, until the in vivo loading modes are known more precisely, an alternative slot-tip shape cannot be proposed.