Condylar Fragment Research Articles

Two load sharing plates fixation in mandibular condylar fractures: Biomechanical basis

Mandibular condylar fractures have a high incidence but there is no consensus regarding the best choice of osteosynthesis. From a review of the literature, it is evident that the technique used most frequently for fixation is the positioning of a single plate despite complications concerning plate fracture or screw loosening have been reported by various authors. Different studies have highlighted that the stability of osteosynthesis is correlated with the mechanical strains occurring in the condylar region, generated by the muscles of mastication. The aim of our study was, through a mandibular finite element model (FEM), to confirm this correlation and to analyse the behaviour of single and double elements of union in the fixation of mandibular subcondylar fractures. We concluded that the use of two plates provides greater stability compared with the single plate, reducing the possibility of displacement of the condylar fragment. Therefore we recommend that this technique should be adopted whenever possible.

A Rare Occipital Condyle Fracture in a Patient With A Minor Head Injury

Occipital condyle fracture (OCF) is an uncommon but potentially fatal disease entity. It is most commonly identified in patients suffering from severe craniocerebral trauma. The advent of computed tomography has made early detection possible. Traditional treatment using a hard neck collar is sufficient to produce solid fusion in most OCF patients. Delayed diagnosis, however, may result in neurologic deterioration due to potential displacement of fractured condylar fragments. Here we report a case of isolated, stable OCF in a patient with a minor head injury. A high level of clinical awareness of this rare disease entity is imperative for the management of traumatized patients, especially for those who have minor head injuries but persistent neck pain.

Twenty-degree-tilt radiography for evaluation of lateral humeral condylar fracture in children

To investigate the efficacy of '20 degrees -tilt anteroposterior (A-P) radiography' in the assessment of lateral condylar fractures of the distal humerus. Eighteen children with lateral humeral condylar fractures were studied. Every child underwent conventional A-P and lateral radiography, and six children underwent multi-detector computed tomography (MDCT). For the investigation of 20 degrees -tilt radiography, ten children with lateral humeral condylar fractures had conventional and 20 degrees -tilt A-P and lateral radiography both preoperatively and postoperatively. Fragment dislocation was measured at the lateral and medial margins of the fracture on both the conventional A-P and 20 degrees -tilt A-P radiographs. The lateral condylar fragment was triangular and was most prominent posteriorly. The fracture line was typically tilted approximately 20 degrees to a reference line perpendicular to the long axis of the humerus in the lateral view. The extent of dislocation at the lateral and medial margins of the fracture site by 20 degrees -tilt A-P radiography (9.3 +/- 3.6 mm and 5.6 +/- 2.5 mm) was significantly wider than that measured by the conventional method (6.8 +/- 4.1 mm and 2.0 +/- 1.5 mm ), which may influence treatment. Twenty-degree-tilt A-P radiography may more precisely demonstrate fragment dislocation than standard radiographs and may influence patient treatment.

Transoral endoscopic-assisted management of subcondylar fractures in 17 patients: An alternative to open reduction with rigid internal fixation and closed reduction with maxillomandibular fixation

The authors evaluate the results of transoral endoscopic-assisted open reduction and miniplate fixation of subcondylar fractures. Seventeen patients were treated from August 2005 to April 2007. Inclusion criteria were: adult patients, inability to achieve adequate occlusion with closed reduction, dislocation of the condylar fragment between 10 and 45°, and 2-mm inter-fragment overlapping. Regular panoramic radiographs were taken postoperatively. Transbuccal incisions were used to place the screws for fixation in 15 patients. Pure intraoral access and angulated drills and screwdrivers were used in 2 patients. The condyle was placed into the condylar fossa in all cases. No damage to the facial nerve was observed. No visible scars were present. Mean surgical time was 80.36 minutes. Transitory hyposthesia was observed in 3 cases. Adequate reduction and consolidation of the fracture was achieved in 16 patients. No condylar reabsortion was present at the end of the follow-up period. The authors consider that transoral endoscopic-assisted open reduction constitutes a valid alternative to a transcutaneous approach for the reduction and fixation of subcondylar fractures in selected cases. It provides the benefits of open reduction and internal fixation without the potential complications. Advice is given on how to achieve adequate reduction and stability of the proximal fragment.

Reduction of diacapitular fractures of the mandibular condyle using a special repositioning pin

The reduction of diacapitular fractures1 of the mandibular condyle can be technically difficult and time-consuming but seems to have a beneficial effect on patients.2,3 The proximal condylar fragment is often considerably displaced medially and caudally by the pull of the lateral pterygoid muscle. Disruption of soft tissue should be kept to a minimum to compromise the blood supply to the proximal fragment as little as possible.4 Previously such a fractures has been reduced using small bone hooks, so a new repositioning pin to assist in reduction and fixation of the proximal condylar fragment with only minimal dissection has therefore been developed.

O.448 Interdisciplinary management of maxillo-facial haemorrhages

Temporomandibular joint (TMJ) function was evaluated following endoscope-assisted transoral open reduction and miniplate fixation of displaced bilateral condylar mandibular fractures. The transoral treatment of bilateral condylar fractures was performed in 13 patients from May 2000 to December 2004. Eleven of the 13 patients had additional mandibular fractures. Out of 26 fractures of the condylar process, 11 were located at the condylar neck and 15 were subcondylar. One, 6 and 12 months after surgery TMJ function was evaluated. Anatomic reduction was achieved using an endoscope-assisted transoral approach even when the condylar fragment was displaced medially and in fractures with comminution. Good TMJ function was noted 6 and 12 months after surgery. Mouth opening was measured to be more than 40 mm without deviation. Postoperative range of motion with a satisfying lateral excursion was found. Early rehabilitation and pre-injury TMJ function was achieved following minimally invasive anatomic fracture reduction.

Application of lateral lag screw with sagittal condylar fracture and management of articular disk

To evaluate the application of lateral lag screw and reduction of articular disk in management of intracapsular sagittle fractures of the condylar process. The study group consisted of 16 cases (19 joints), including 10 males (12 joints) and 6 females (7 joints). Condylar sagittal fracture and displaced articular disk were detected in all patients. The condylar segments were repositioned and fixed by using lateral lag screw and the displaced articular disk were repositioned at the same time. The mean postoperative follow-up was 16 months (range 6-28 months). During the follow up, facial nerve function was monitored and radiologic re-examinations were performed to evaluate reposition of condylar process fractures and articular disk, while the mouth opening and occlusion were registered. The reduction of the displaced condylar fragments and articular disks in all patients were excellent on 3D CT and MRI. No severe complications were observed (including permanent facial nerve palsies, malocclusion, ankylosis). Three months after surgery, all patients showed their better mobility with condylar and disk, and mouth opening reached 43 mm on maximum, 32 mm on minimum, with a mean of 37 mm. The results by application of lateral lag screw and reduction of articular disk are helpful in anatomical and functional recovery of temporomandibular joint for patients with displaced sagittal condylar process fractures.

Poster Session: 12th Annual Conference of Iscas

Resumen del poster presentado a la 12th Annual Conference of the International Society for Computer Aided Surgery Sessions (ISCAS) celebrada en Barcelona del 25 al 28 de junio de 2008.

Surgical Treatment of Late Presented Displaced Lateral Condylar Fracture of the Humerus in Children

Purpose: To determine whether late open reduction and internal fixation (ORIF) of a lateral condylar fracture (LCF) after 3 weeks is possible, and to determine the latest time for ORIF without a bone graft. Materials and Methods: Eight children underwent late ORIF (＞3 weeks) of a displaced LCF (＞2.5 ㎜) of the humerus between 3 weeks and 5 weeks after injury. Results: Clinically, results were excellent in 6 cases and good in 2 cases. There was no serious complication, including nonunion and avascular necrosis (AVN), though 2 cases had a slight fishtail deformity and mild carrying angle loss due to overgrowth of the lateral condyle fragment. Conclusion: We believe that 3 weeks is too short to deny open reduction and anatomic reduction for fear of AVN of a late presented lateral condyle fracture of the humerus. The latest time for ORIF in late presented LCF in children is around 5 weeks, and surgical treatment may even be possible after greater delays.

Transepiphyseal Elbow Injuries: An Approach To Diagnosis And Literature Review

An eight year old boy was admitted following direct trauma to the elbow sustained following a fall. The elbow was oedematous, deformed and tender with decreased range of movement. The initial impression, clinically and on X-rays was that of elbow dislocation. Intraoperatively, he was found to have a transepiphyseal injury which was treated with K-wiring. Radiological appearances can be deceptive in the diagnosis of transepiphyseal injuries. We looked at previous literature on similar cases and aim to define the features suggestive of a transepiphyseal injury. We further suggest pre-operative and intra-operative methods to differentiate common elbow pathologies which present similarly. INTRODUCTION Fractures around the elbow in children are often difficult to diagnose. Transepiphyseal elbow injuries are rare injuries and can be easily misinterpreted on radiographs. Various traumatic pathologies around the elbow present similarly and encompass a wide spectrum including the pulled elbow to difficult Transepiphyseal dislocations. We present the case of an eight year-old boy, who sustained an epiphyseal injury to the left elbow following a fall and look at the ways to diagnose this injury with the aid of Schematic diagrams to illustrate the anatomical relationships in a normal elbow (Fig 1). Transepiphyseal Elbow Injuries: An Approach To Diagnosis And Literature Review 2 of 6 Figure 1 Figure 1: Normal elbow CASE REPORT An eight year old boy fell onto his left elbow and presented in casualty with a painful deformed elbow without any distal neuro-vascular deficits. Radiographs on admission were interpreted and reported as a dislocation of the elbow (fig 2a & b). Figure 2 Figure 2a: Lateral pre-op Figure 3 Figure 2b: AP pre-op Intraoperative radiographic screening revealed a transepiphyseal fracture without a dislocation of the elbow, Transepiphyseal Elbow Injuries: An Approach To Diagnosis And Literature Review 3 of 6 as shown in the schematic diagram (fig 2c). Figure 4 Figure 2c: Schematic diagram The fracture was treated by open reduction and internal fixation with Kirschner wires (figs 3a & b). The fracture united and the wires were removed at six weeks. Figure 5 Figure 3a: AP after fixation Transepiphyseal Elbow Injuries: An Approach To Diagnosis And Literature Review 4 of 6 Figure 6 Figure 3b: Lat post fixation DISCUSSION In 1850 RW Smith first described this injury and differentiated it from supracondylar fracture and elbow dislocation. Clinical examination is often not possible due to the pain and the swelling associated with the injury. On a plain radiograph it is important to distinguish transepiphyseal injury from lateral condyle fracture (fig 4) and dislocation of the elbow. Figure 7 Figure 4: Lateral condyle fracture The difficulty lies in being unable to visualize the cartilaginous distal humeral epiphysis on plain radiograph. Mizuno et al2 used the relationship of the capitellum to the axis of the head of the radius and to the humerus. In transepiphyseal injury the capitellum maintains its relationship to the head of the radius but not with the humerus, whereas in the fracture of the lateral condyle the axes of the humerus to the forearm is maintained and the relationship of the condylar fragment to the radial head may be altered depending on the displacement of the fracture. In elbow dislocation the relationship of the capitellum to the radius is changed while its relationship to the humerus is maintained. Another difference seen is that the displacement in transepiphyseal injury is commonly postero-medial1 whereas it is most often postero-lateral in dislocation of the elbow. The diagnosis can further be confirmed with an Transepiphyseal Elbow Injuries: An Approach To Diagnosis And Literature Review 5 of 6 arthrogram intraoperatively2. The principle in the management of such fractures lies in early reduction (closed1 or open2) and internal fixation. CONCLUSION As in our case transepiphyseal injuries are often misinterpreted on plain radiographs. A mental impression of the distal humerus including its cartilaginous portion and knowledge of the anatomical relationship of the various ossific nuclei is helpful in the diagnosis of the injury.

Preliminary functional results of endoscope-assisted transoral treatment of displaced bilateral condylar mandible fractures

Temporomandibular joint (TMJ) function was evaluated following endoscope-assisted transoral open reduction and miniplate fixation of displaced bilateral condylar mandibular fractures. The transoral treatment of bilateral condylar fractures was performed in 13 patients from May 2000 to December 2004. Eleven of the 13 patients had additional mandibular fractures. Out of 26 fractures of the condylar process, 11 were located at the condylar neck and 15 were subcondylar. One, 6 and 12 months after surgery TMJ function was evaluated. Anatomic reduction was achieved using an endoscope-assisted transoral approach even when the condylar fragment was displaced medially and in fractures with comminution. Good TMJ function was noted 6 and 12 months after surgery. Mouth opening was measured to be more than 40 mm without deviation. Postoperative range of motion with a satisfying lateral excursion was found. Early rehabilitation and pre-injury TMJ function was achieved following minimally invasive anatomic fracture reduction.

Pathological changes after the surgical creation of a vertical intracapsular condylar fracture

The aim of this study was to create in a sheep model an intracapsular oblique vertical split fracture, and observe the histopathological changes in the temporomandibular joint (TMJ) condylar head. In 10 sheep, the right TMJ was operated through the preauricular region. The anterior and posterior attachments of the disc were cut; an oblique vertical osteotomy was made from the lateral pole of the condyle to the medial side of condylar neck. The condylar fragment was pushed anteriorly, inferiorly and medially together with the disc. The non-operated left TMJ served as control. Two sheep were killed at 1 week and four at both 4 and 12 weeks. Computed tomography scans were taken and histopathological changes of the joint observed. There was severe bone erosion and a new bony outgrowth on the lateral side of the condylar stump and temporal bone. The joint spaces were filled with fibrous tissue, cartilage tissue and bone in the 4 and 12 weeks operated groups. These results show that an oblique vertical intracapsular fracture through the lateral condylar pole, combined with an anteriorly and medially displaced condylar fragment and disc and damaged lateral capsule, are likely to result in the pathological changes of osteoarthritis, and the progressive development of ankylosis in a sheep TMJ.

A Sheep Model of Intracapsular Condylar Fracture

An animal model of a condylar head fracture similar to a type B intracapsular fracture in humans was created. The effect of this model on mandibular function and morphological changes of temporomandibular joint (TMJ) structure was evaluated. Ten sheep were divided into 3 groups, sacrificed at 1 week (2 sheep), 4 weeks (4 sheep), and 12 weeks (4 sheep) after surgery. The right side of the TMJ was considered the surgical group; the left side, the control group. The anterior and posterior attachments of the discs were cut, and an oblique vertical osteotomy was made from the lateral pole of the condyle to the medial side of the condylar neck. The condyle fragment was pushed together with the disc anteriorly, inferiorly, and medially. The lateral side of the condylar stump was sutured to the capsule to limit movement. Preoperative and postoperative body weight, maximum mouth opening, lateral excursions, and x-ray and computed tomography (CT) findings in the 3 surgical groups and the control group were recorded. The SPSS software program was used for all statistical analyses. There were no significant differences in weight loss and left lateral movement among the 3 surgical groups, but maximum mouth opening and the right lateral movement decreased significantly in the 4-week and 12-week surgical groups. X-rays demonstrated severe bone erosion and new bony outgrowth in the lateral side of the condylar stump and a narrowed, indistinct joint space in these 2 groups. Three-dimensional reconstruction of CT images showed changed contours of the condylar stump, condylar fragment and articular eminence in all 3 surgical groups. This study demonstrates progressive changes toward ankylosis and pathological changes in sheep TMJ over time consistent with what has been found in humans.

Development and biomechanical testing of a new osteosynthesis plate (TCP ®) designed to stabilize mandibular condyle fractures

In this paper, the different steps of development and experimental validation of a new type of three-dimensional (3-D) trapezoidal osteosynthesis plate (Modus TCP 2.0, Medartis, Basel, Switzerland) is described. These plates have been designed to stabilize sub-condylar and condylar neck fractures of the mandible. In order to apply the principles of functionally stable osteosynthesis to the mandibular condyle, i.e. to put the plate as close as possible to the tensile strain lines occurring during function, two new 4- and 9-hole 3-D trapezoidal plates were designed. Tests were conducted on fresh human mandibles before and after osteosynthesis of a standardised unilateral sub-condylar 'fracture', and a static biting exercise between the ipsilateral first molars was reproduced on a test bench. The resulting condylar fragment displacement in the sagittal plane was measured and the alterations of the condylar tensile strain lines induced by the osteosynthesis were investigated by using photoelastic strain tests. None of the plates broke. No macroscopic condylar displacement was noted when assessing the quality of the primary stabilization. Strain analysis showed the ability of these 3-D plates to transmit physiological strains across the fracture line and the absence of potentially damaging strains around the plate. These results were accredited to the 3-D and trapezoidal features of the plates. The Modus TCP plates experimentally fulfil the principles of functionally stable osteosynthesis in the condylar region and are able to resist physiological strains.

A knee-sparing distal femoral endoprosthesis using hydroxyapatite-coated extracortical plates

We used a knee-sparing distal femoral endoprosthesis in young patients with malignant bone tumours of the distal femur in whom it was possible to resect the tumour and to preserve the distal femoral condyles. The proximal shaft of the endoprosthesis had a coated hydroxyapatite collar, while the distal end had hydroxyapatite-coated extracortical plates to secure it to the small residual femoral condylar fragment. We reviewed the preliminary results of this endoprosthesis in eight patients with primary bone tumours of the distal femur. Their mean age at surgery was 17.years (14 to 21). The mean follow-up was 24 months (20 to 31). At final follow-up the mean flexion at the knee was 102 degrees (20 degrees to 120 degrees) and the mean Musculoskeletal Tumour Society score was 80% (57% to 96.7%). There was excellent osteointegration at the prosthesis-proximal bone interface with formation of new bone around the hydroxyapatite collar. The prosthesis allowed preservation of the knee and achieved a good functional result. Formation of new bone and remodelling at the interface make the implant more secure. Further follow-up is required to determine the long-term structural integrity of the prosthesis.

O.474 Biomechanical photoelastic study comparison of conventional and uni-lock systems for mandibular osteosynthesis

The authors evaluate the results of transoral endoscopic-assisted open reduction and miniplate fixation of subcondylar fractures. Seventeen patients were treated from August 2005 to April 2007. Inclusion criteria were: adult patients, inability to achieve adequate occlusion with closed reduction, dislocation of the condylar fragment between 10 and 45°, and 2-mm inter-fragment overlapping. Regular panoramic radiographs were taken postoperatively. Transbuccal incisions were used to place the screws for fixation in 15 patients. Pure intraoral access and angulated drills and screwdrivers were used in 2 patients. The condyle was placed into the condylar fossa in all cases. No damage to the facial nerve was observed. No visible scars were present. Mean surgical time was 80.36 minutes. Transitory hyposthesia was observed in 3 cases. Adequate reduction and consolidation of the fracture was achieved in 16 patients. No condylar reabsortion was present at the end of the follow-up period. The authors consider that transoral endoscopic-assisted open reduction constitutes a valid alternative to a transcutaneous approach for the reduction and fixation of subcondylar fractures in selected cases. It provides the benefits of open reduction and internal fixation without the potential complications. Advice is given on how to achieve adequate reduction and stability of the proximal fragment.

Plating treatment for tibial plateau fractures: a biomechanical comparison of buttress and tension band positions

The load tolerance of conventional plate treatment for bicondylar tibial plateau fractures with the buttress and the tension band positions was compared from biomechanical viewpoints. Fourteen left synthetic tibiae divided into two groups were tested. T-plates in the buttress group were placed on the medial tibial subcondyle and T-plates in the tension band group were placed on the lateral tibial subcondyle. All specimens were evaluated with a Material Testing System (MTS) machine. A linear variance displacement transducer gauge was placed on the medial tibial subcondyle. The anatomic axis of the synthetic femur and the tibia was maintained at 6 degrees varus in the frontal plane. The MTS actuator was set to increase displacement at 3 mm/min. All specimens were evaluated to failure. The relative motion and the ultimate failure load (UFL) between both groups were compared. The buttress group had significantly less displacement than the tension band group following the incrementally increased loading (p < 0.001). At failure, the buttress group also had a higher UFL (p < 0.001) and less displacement (p = 0.009) than the tension band group. All medial tibial condylar fragments achieved improved stabilization from the medial aspect of the proximal tibia by conventional plates. When conventional plates cannot be placed medially due to skin ailments, lateral placement of conventional plates may have the insufficient stability. Protected weight bearing should be followed strictly.

Biomechanical Comparison of Orthofix Pins and Cortical Bone Screws in a Canine Humeral Condylar Fracture Model

To compare shear stability of simulated humeral lateral condylar fractures reduced with either a self-compressing pin or cortical bone screw. In vitro biomechanical tests. Bilateral cadaveric canine humeri (n=18) without evidence of elbow disease. Lateral condylar fracture was simulated by standardized osteotomy. Bone fragments were stabilized with a self-compressing pin or a cortical bone screw (2.7 or 3.5 mm) inserted in lag fashion. Specimens were mounted in a materials testing system and the condylar fragment displaced in a proximal direction until failure. Mechanical testing variables derived from load-deformation curves were compared between stabilization methods using a Student's paired t-test. There were no statistically significant differences for mechanical testing variables between pin and screw stabilized specimens at expected walk and trot loads. Three yield points subjectively coincided with yield of the interfragmentary interface (Y1), bone at the implant interface (Y2), and implant deformation (Y3). Displacements at Y1 were 48-156% greater for pin than screw stabilized specimens. Y2 and Y3 loads were higher for screw than pin stabilized specimens, but likely supraphysiologic for dogs convalescing after surgical repair. A self-compressing pin or a cortical bone screw inserted in lag fashion both provided adequate strength in applied shear to sustain expected physiologic loads through the repaired canine elbow during postoperative convalescence. Because self-compressing pins were easy to implant and mechanical properties were not significantly different than cortical screws at expected physiologic loads, pins should be considered for the repair of traumatic humeral condylar fractures.

Preservation of Disc for Treatment of Traumatic Temporomandibular Joint Ankylosis

A new operating method was used to treat traumatic temporomandibular joint (TMJ) ankylosis, to restore the structure of the TMJ, to improve the secondary maxillofacial deformity, and prevent recurrence of TMJ ankylosis. Thirty-six patients (20 females, 16 males; aged 5 to 54 years old) with TMJ ankylosis type II or III of 1 to 16 years' duration, with a maximal mouth opening from 0 to 15 mm preoperatively participated. The new method was to separate bony fusion between condyle and glenoid fossa, remove the condylar fragment that displaced medially or anteroinferiorly, mobilize the remains of the disc over the condylar stump and suture it with articular capsule, and shave the surface of the condylar stump and glenoid fossa smooth. Follow-up was performed from 1 to 7 years postoperatively in 21 cases. No recurrences occurred in patients whose TMJ disc was retained during operation. Patients had an average maximal mouth opening of 33.7 mm postoperatively. An 11-year-old patient showed an improved facial symmetry after surgery. By restoring the normal structure of the TMJ and preservation of the disc, recurrence of traumatic TMJ ankylosis and facial deformity in younger patients can be prevented.

Occipital condyle fractures: report of five cases and literature review

Occipital condyle fractures (OCFs) are uncommon and potentially fatal lesions. After the advent of CT, prompt diagnosis can be readily made and consequently better prognosis of these patients is expected. Early recognition of some types of OCF is imperative to avoid fatal results. We analyzed 121 cases of OCF (116 from the literature and five of our own). Rarely patients with a deficit of the lower cranial nerves make a complete recovery. However, quoad vitam prognosis of patients with "pure OCFs" remains good. Immobilization provides good recovery of most OCFs, but delay of treatment can lead to serious morbidity. We want to emphasize that not only an OCF with instability of O-C1-C2 can be a fatal injury unless prompt surgical intervention, but a displacement and migration of the fractured condylar fragment can also result in a fatal outcome. A high level of suspicion is fundamental for the early diagnosis of these fractures, so that when a posterior basal cranial or occipital squama fracture occurs, a CT study of the occipital condyles becomes imperative.