Condylar Resection Research Articles

Far lateral approach: Is condylar resection required?

We report our experience with the far lateral approach (FLA) and its modifications in the surgical resection of tumors of craniocervical junction (CCJ). We retrospectively reviewed data of 36 patients with CCJ lesions who underwent surgical excision. Data are presented as frequency/percentages. Tumor locations were classified by anatomical relation around the CCJ (on axial plane). For anterior and laterally placed tumors, we preferred the FLA and its modification. A postoperative complication was defined as a new neurological deficit without subsequent recovery. The perioperative mortality was defined as death within 30 days of surgery. The mean age of the study population was 48.8 years (5-64 years) with 15 women. Simpson's Scale Grade 2 resection was achieved in 18 out of 19 patients with meningiomas. Overall, transient complications were observed in eight patients (22%); none of the patients developed postoperative cerebrospinal fluid fistula. The permanent morbidity rate was 5.6%. One patient died on the 6th postoperative day. The mean follow-up period was 4.1 years (range, 3 months-12 years). Tumor recurrence was observed in two patients who were advised radiotherapy. Twenty patients (96%) were independent for activities of daily living. The FLA is a versatile approach and is useful for a variety of lesions located ventrolateral to the brainstem and upper cervical cord. It allows adequate exposure with minimal retraction. Most of the foramen magnum meningiomas can be excised either without or with only partial resection of the condyle. The transjugular process approach to the jugular foramen (JF) is effective for JF tumors without the necessity of facial nerve transposition.

The far-lateral approach: destruction of the condyle does not necessarily result in clinically evident craniovertebral junction instability.

OBJECT Far-lateral or extreme-lateral approaches to the skull base allow access to the lateral and anterior portion of the lower posterior fossa and foramen magnum. These approaches include a certain extent of resection of the condyle, which potentially results in craniocervical junction instability. However, it is debated what extent of condyle resection is safe and at what extent of condyle resection an occipitocervical fusion should be recommended. The authors reviewed cases of condyle resection/destruction with regard to necessity of occipitocervical fusion. METHODS The authors conducted a retrospective analysis of all patients in whom a far- or extreme-lateral approach including condyle resection of various extents was performed between January 2007 and December 2014. RESULTS Twenty-one consecutive patients who had undergone a unilateral far- or extreme-lateral approach including condyle resection were identified. There were 10 male and 11 female patients with a median age of 61 years (range 22-83 years). The extent of condyle resection was 25% or less in 15 cases, 50% in 1 case, and greater than 75% in 5 cases. None of the patients who underwent condyle resection of 50% or less was placed in a collar postoperatively or developed neck pain. Two of the patients with condyle resection of greater than 75% were placed in a semirigid collar for a period of 3 months postoperatively and remained free of pain after this period. At last follow-up none of the cases showed any clear sign of radiological or clinical instability. CONCLUSIONS The unilateral resection or destruction of the condyle does not necessarily result in craniocervical instability. No evident instability was encountered even in the 5 patients who underwent removal of more than 75% of the condyle. The far- or extreme-lateral approach may be safer than generally accepted with regard to craniocervical instability as generally considered and may not compel fusion in all cases with condylar resection of more than 75%.

Endoscopic Endonasal Transclival Transcondylar Approach for Foramen Magnum Meningiomas: Surgical Anatomy and Technical Note.

The endoscopic endonasal approach provides a direct route to ventral foramen magnum (FM) lesions like meningiomas, which are difficult to access. Endonasal access at the FM is limited laterally by the occipital condyles and inferiorly by the C1 anterior arch and the odontoid process, which may need partial resection. We investigated the surgical anatomy and technical nuances for endonasally increasing the surgical corridor at the FM region both laterally and inferiorly. Unique to our report, we quantified the amount of required medial condyle resection to obtain exposure of the lateral aspects of the FM. Five fresh human head silicone-injected specimens underwent endonasal inferior transclival, transcondylar approaches. The lateral limit of medial condyle resection was defined using a vertical line extending inferiorly from foramen lacerum and its intersection with the occipital condyle. The condylectomy was limited posteriorly by the cortical bone surrounding the hypoglossal canal. The volume of the resected condyle (cubic centimeters) for 10 sides was measured using the pre- and postdissection computed tomography-volumetric analysis. The mean percentage condylar volume resected during a unilateral medial condylectomy was 18% (9.7%-28.3%). The surgical corridor was extended inferiorly in all specimens without violating the transverse ligament by drilling the superior aspects of C1 anterior arch and the exposed odontoid tip. These operative nuances were successfully applied in the operating room. Anatomical landmarks can reliably guide an endonasal anteromedial condyle resection. Minimal condyle resection is required to widen lateral access at the FM, which minimizes the risk of craniocervical instability.

Cone beam computed tomography-based models versus multislice spiral computed tomography-based models for assessing condylar morphology

To quantitatively compare condylar morphology using cone beam computed tomography (CBCT) and multislice spiral computed tomography (MSCT) virtual three-dimensional surface models. The sample consisted of secondary data analyses of CBCT and MSCT scans obtained for clinical purposes from 74 patients treated with condylar resection and prosthetic joint replacement. Three-dimensional surface models of 146 condyles were constructed from each scan modality. Across-subject models were approximated and voxel-based registration was performed between homologous CBCT and MSCT images, making it possible to create average CBCT- and MSCT-based condylar models. SPHARM-PDM software provided matching points on each corresponding model. ShapeAnalysisMANCOVA software assessed statistically significant differences between observers and imaging modalities. One-sample t-tests evaluated the null hypothesis that the mean differences between each CBCT- and MSCT-based model were not clinically significant (<.5 mm). Tests were conducted at a significance level of P < .05. ShapeAnalysisMANCOVA showed no statistically significant difference between the average CBCT- and MSCT-based models (P > .68). During pairwise comparison, the mean difference observed was .406 mm (SD, .173). One sample t-test showed that mean differences between each set of paired CBCT- and MSCT-based models were not clinically significant (P = .411). Three-dimensional surface models constructed from CBCT images are comparable to those derived from MSCT scans and may be considered reliable tools for assessing condylar morphology.

Exploitation of Simple Classification and Space Created by the Tumor for the Treatment of Foramen Magnum Meningiomas

The resection of foramen magnum meningiomas (FMMs) presents neurosurgical challenges. We propose a simple classification of the tumor location and the operating space created by the tumor to help treatment planning. We retrospectively analyzed 16 FMMs and divided them into 3 groups based on the tumor location--clival, foraminal, and atlantal tumors. The distance between the condyle and the neuraxis at the level of the foramen magnum was measured and defined as the available operative space (AOS). We also reviewed intraoperative video recordings to assess the surgical exposure of the tumor by the space created by the FMM and compared it with the AOS. There were 4 clival, 8 foraminal, and 4 atlantal tumors. The AOS of the clival tumors was 10 mm ± 1.7, the AOS of the foraminal tumors was 18 mm ± 3.7, and the AOS of the atlantal tumors was 12 mm ± 2.1. All foraminal and atlantal tumors could be detached without a brain retractor. Because a major portion of the clival tumors was covered by the spinomedullary junction, a brain spatula was needed to obtain the required surgical space. The difference in AOS between clival and foraminal/atlantal tumors was statistically significant (P = 0.044). Although 4 patients experienced postoperative complications, the average postoperative Karnofsky performance scale score improved. The surgical complication rate was significantly lower in foraminal and atlantal FMMs than in clival FMMs (P = 0.027). The simple classification of the tumor location helped to assess surgical difficulties. Knowledge of the space created by the FMMs between the condyle and the neuraxis is useful for planning the approach strategy, especially for estimating the available working space without resection of the occipital condyle.

Surgical approaches to jugular foramen schwannomas: An anatomic study.

The variety of surgical approaches to jugular schwannomas makes selection of an approach difficult. The purpose of this study was to define the anatomic elements of these approaches. Ten adult cadaveric heads were examined. There are lateral, posterior, and anterior routes that access various parts of the jugular foramen. Removal of the jugular process of the occipital bone provides access to the posterior aspect of the foramen, the infralabyrinthine mastoidectomy provides access to the lateral edge and dome of the jugular bulb, and the preauricular approaches provide access to the anterior margin of the bulb and foramen. Additions to these approaches may include cervical and vertebral artery exposure, facial nerve transposition, foramen magnum exposure, and external canal and condylar resection. An understanding of the anatomy of the jugular foramen is crucial in achieving total tumor removal while minimizing risk. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1041-E1053, 2016.

Atlanto-occipital Instability Following Endoscopic Endonasal Approach for Lower Clival Lesions: Experience With 212 Cases.

The endoscopic endonasal approach (EEA) for craniocervical lesions involving the lower clivus and occipital condyles carries an unclear risk of atlanto-occipital (AO) instability requiring arthrodesis. Elucidate risk factors for AO instability following EEA for clival lesions. We reviewed patients with clival tumors who underwent EEA at our institution between 2002 and 2012. Resection of the lower clivus, foramen magnum, AO joint, and occipital condyles were evaluated on fine-cut postoperative computed tomography. Two hundred twelve patients (mean age 47.9 years, 57.1% male) underwent transclival EEA for lower clival lesions. In addition to the lower clivus, resection involved the condyle in 14.2% of patients, the foramen magnum in 16.5%, and the AO joint in 1.4%. Quantification of condyle resection revealed complete resection in 3 cases, 75% resection in 8 cases, 50% resection in 6 cases, and 25% resection in 13 cases. Seven of these patients had EEA combined with an open, far-lateral approach. In total, 7 patients required arthrodesis following EEA (3.3%), 4 of them after a combined approach. All patients who underwent arthrodesis had primary bone tumors such as chordoma, chondrosarcoma, or osteosarcoma (P = .022). Degree of condyle resection was a significant factor predisposing to occipitocervical instability (P = .001 and P < .001 for 75% and 100% condyle resection, respectively). Use of a combined approach was significantly associated with arthrodesis (P < .001). EEA resection of the occipital condyles that results in greater than 75% condyle resection or EEA in combination with an open approach significantly increases the risk of AO instability and likely necessitates AO fixation. AO, atlanto-occipitalEEA, endoscopic endonasal approachOC, occipitocervical.

Treatment of Dentofacial Deformities Secondary to Osteochondroma of the Mandibular Condyle Using Virtual Surgical Planning and 3-Dimensional Printed Surgical Templates

One-stage treatment for condylar osteochondroma and secondary facial deformities by resection and reconstruction of the mandibular condyle, orthognathic surgery, and mandibular contouring has been reported recently. This study investigated the clinical feasibility of treating osteochondroma of the mandibular condyle and secondary dento-maxillofacial deformities by virtual surgical planning and 3-dimensional (3D) printed surgical templates. A composite skull model with accurate dentition was obtained with data from spiral computed tomography (CT) and surface scanning of the dental arch. Virtual surgical simulation was performed using Dolphin Imaging 11.7 Premium and Mimics software after a comprehensive 3D diagnosis and surgery planning. Surgical templates were fabricated by 3D printing using data from virtual surgical simulation for guidance of excision of the mandibular condyle with osteochondroma, reconstruction of the mandibular condyle, mandibular contouring, and reconstruction of a normal occlusion. Le Fort I osteotomy of the upper jaw and genioplasty were performed when indicated. The linear difference between virtually simulated and postoperative skull models was evaluated. All surgeries were successfully simulated using virtual surgical planning, and the guiding templates were successfully applied for all patients. Successful reconstruction of condylar function, normal occlusion, and symmetry of the facial profile was achieved. Postoperative CT scans and quantitative analysis showed that virtual surgical plans provided acceptable accuracy in the operating room. The linear difference of the incisors and first molars was no more than 1.4 mm, and the greatest difference was found for the menton landmark, which was up to 2.4 mm. Results from this study suggested that virtual surgical planning and guiding templates facilitated accurate diagnosis, treatment planning, accurate osteotomy, repositioning of bony segments, and contouring of the mandibular border in the treatment of condylar osteochondroma and secondary facial asymmetry.

Biomechanical effects of the transcondylar approach on the craniovertebral junction.

The transcondylar variation of the far-lateral, retrosigmoid approach is intended for pathologies in the anterolateral portion of the foramen magnum. That area is more clearly visualized when a fraction of the ipsilateral occipital condyle is removed. In this study, the biomechanical effect of this approach on occiput-C2 rotation was investigated. Our hypothesis was that the biomechanical characteristics are significantly altered following the transcondylar approach. Five human cadaveric upper cervical spine specimens (occiput-C7) were used in the study. Torsional moments were applied from zero to a maximum of 1.5 N m to the left and to the right using a mechanical testing machine. The resulting rotational motions of the O-C1, C1-2, and O-C2 segments were measured in the intact specimen and after a simulated right-sided transcondylar approach with resection of 2/3 of the condyle, confirmed by CT scanning and visual inspection. After the posterior two-thirds of the occipital condyle were removed, the neutral zone (NZ) increased 1.3° to the left and 2° to the right at C0-C1, and 7.4° to the left and 6.2° to the right at C1-2. The cumulative increase in NZ between O and C2 was 8.7° to the left and 8.2° to the right. The transcondylar approach also resulted in significant increases in range of motion (ROM) in axial rotation to both sides in all segments. ROM increased 2.8° to the left and 2.4° to the right between C0 and C1, 7.3° to the left and 5.4° to the right between C1 and C2, and 10.1° to the left and 7.8° to the right between CO and C2. Upon inspection, the area of the occipital condyle where the alar ligament attaches had been completely removed in three of the five specimens. Removing the posteromedial two-thirds of one occipital condyle alters the normal axial rotational movements of the craniovertebral junction on both sides. The insertion of the alar ligament can be inadvertently removed during condylar resection, and this could contribute to atlanto-axial instability. There is a biomechanical substrate to cranio-cervical instability following a transcondylar approach; these patients may need to be followed over several years to ensure it does not progress and necessitate occipito-cervical fusion.

CORR Insights®: A new method for calculating femoral anterior cortex point location and its effect on component sizing and placement.

T he study by Mahfouz and colleagues provides a number of interesting arguments regarding distal femoral preparation in TKA. Traditional instrumentation systems provide surgeons with flexibility in component placement; however, these systems can introduce potential errors in alignment and bone resection planes. Different knee systems have variable implant thicknesses and progression between sizes, making instrumentation comparisons even more difficult. The use of computer navigation or patient-specific guides may eliminate some of these errors but can potentially create new ones. With computer navigation, inaccuracies in registration may create erroneous alignment and resection planes. Any movement of fixed referencing guides can also lead to incorrect resection planes. For patient-specific guides, incorrect templating for surgical planning, or incorrect placement of the cutting guide may lead to incorrect resection planes. Furthermore, to balance the ligaments with patientspecific guides, additional bone resection is often required. In addition, the distal femoral anatomy shows significant variation between individuals and current total knee implants can only approximate that anatomy. While alignment is important, the success of a TKA may be better defined by the kinematics of the reconstructed whole. This paper demonstrates some of the variability that can occur based on the use of specific landmarks for distal femoral bone preparation. The greatest variation detected was in the amount of posterior condylar bone resected with the various techniques. This error is inherent in systems that use anterior cortical referencing and is clearly shown by the data. The use of a PCA+3 posterior condylar resection may be correct in many knees, but when using a ligament balancing technique could be shown to be incorrect as much as 40% of the time. The distal femoral flexion discrepancy between the mechanical axe (MA)-1 and MA-2 technique raises an important point with regard to positioning of the femoral implant. Relative extension of the distal femoral cut will alter This CORR Insights is a commentary on the article ‘‘A New Method for Calculating Femoral Anterior Cortex Point Location and Its Effect on Component Sizing and Placement’’ by Mahfouz and colleagues available at: DOI: 10.1007/s11999-0143930-1. The author certifies that he, or any member of his immediate family, has no funding or commercial associations (eg, consultancies, stock ownership, equity interest, patent/ licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research editors and board members are on file with the publication and can be viewed on request. The opinions expressed are those of the writers, and do not reflect the opinion or policy of CORR or the Association of Bone and Joint Surgeons. This CORR Insights comment refers to the article available at DOI: 10.1007/s11999-0143930-1. D. A. Fisher MD (&) Center for Joint Replacement, Indiana Orthopedic Hospital, 8450 Northwest Blvd, Indianapolis, IN 46278, USA e-mail: dafisher@orthoindy.com; dafishermd@aol.com CORR Insights Published online: 7 October 2014 The Association of Bone and Joint Surgeons1 2014

Is a "sulcus cut" technique effective for determining the level of distal femoral resection in total knee arthroplasty?

Determining the level of distal femoral resection is crucial when performing total knee arthroplasty (TKA). However, variations in distal femoral resection are encountered unexpectedly. A "sulcus cut" technique is sometimes used to determine the level of distal femoral resection, but its effectiveness has not been evaluated. The aim of this study was to examine the reliability of the sulcus cut technique using computer simulation for preoperative planning. This study group comprised 40 knees in 34 patients (22 women, 12 men) scheduled for TKA. The preoperative planning software of a computed tomography (CT)-based navigation system was used. We determined the resected level of the femur so that the bone-implant interface of the femoral component was adjusted to the deepest subchondral bone of the trochlear groove in coronal CT images. We then measured each perpendicular distance from the resected surface of the proximal femur to the most distal point of the lateral and medial femoral condyles. The mean distances of the distal-lateral and distal-medial condylar resections from the femoral sulcus were 7mm (±1mm) and 8mm (±1mm), respectively. The resection level did not differ significantly between men and women or between different component sizes. There was a slightly positive correlation between the femoral mechanical and anatomical axis angle and the distance of the distal-lateral condylar resection from the femoral sulcus. The sulcus cut technique can be used to determine the desirable level of the distal femoral resection in TKA. Case series, Level IV.

Far lateral paracondylar versus transcondylar approach in the pediatric age group: CT morphometric analysis

This study aimed to determine if partial removal of the occipital condyle provides a significant increase in visibility and "angle of attack" for treating lesions with extension ventral to the brainstem in children using CT morphometric data. Morphometric analysis was performed in 199 children using CT scans. Angle of attack was measured for both the paracondylar and transcondylar far lateral approach. Statistical analysis was performed using paired or unpaired Student's t-tests (p<0.05) and linear regression analysis. For the far lateral paracondylar approach, the overall angle of attack was 85 ± 9 degrees (range, 60-119 degrees). The overall angle of attack for the far lateral transcondylar approach was 70 ± 9 degrees (range, 48-105 degrees). This difference was significant (p<0.0001). Based on our data, resection of one-third of the occipital condyle in a far lateral transcondylar approach can improve angle of attack by approximately 15 degrees, regardless of age or sex, in the pediatric age group. It is important to keep in mind that there are risks attendant to resection of the occipital condyle, thus the resection of the occipital condyle in children should not be a mandatory part of the far lateral approach; rather, the decision-making should be individualized and considered on a case-by-case basis.

Transcondylar Fossa Approach for Cerebellopontine Angle and Ventral Brainstem Lesions: Microsurgical Experiences and Avoidance of Complications

To treat the large tumors located in cerebellopontine angle (CPA) and vascular pathologies including aneurysms and dissection located around the ventral brainstem, transcondylar fossa approach (TCFA) has been regarded as less invasive one. Overall 10 patients had large tumors (D> 3 cm) including schwannomas (n = 8) and meningiomas (n = 2) located in the CPA and 17 patients had vascular pathologies including vertebra-basilar artery aneurysms (n = 14) and dissection (n = 3). Anatomical aspects of the condylar fossa, occipital condyle, and adjacent neurovascular structures were evaluated preoperatively and postoperatively using a three-dimensional computed tomography and magnetic resonance imaging. Gross-total removals in tumor patients achieved without resection of the occipital condyle. In 10 patients with saccular aneurysms, the aneurysms were clipped without resection of the occipital condyle and in 4 patients, partial resection of the condyle and jugular tubercle was necessary to obtain proximal control of the vertebral artery. We met two cases with vertebral artery injury and one case with postoperative cerebrospinal fluid. Transcondylar fossa approach was less invasive technique with minimal or no resection of the occipital condyle comparing with other approaches to ventral brainstem. To avoid complications, anatomical knowledge on the joint and the condylar veins should be reviewed.

Oral Rehabilitation Outcomes After Free Fibula Reconstruction of the Mandible Without Condylar Restoration

Resection of the posterior mandible for tumor or osteonecrosis may include the mandibular condyle, an integral part of the temporomandibular joint (TMJ). Condylar reconstruction, including use of prostheses, the native condylar head, or part of the fibula, all have associated drawbacks including skull base erosion and the potential for ankylosis and TMJ dysfunction as well as the increased difficulty associated with trying to recapitulate the TMJ with high fidelity. We report our experience leaving a single side of the reconstructed mandible unsecured to the glenoid fossa, allowing the mandible to "hang." We hypothesized that a good functional recovery may be achieved with this simple approach while avoiding the potential for ankylosis and TMJ dysfunction. A retrospective chart review of all patients undergoing free fibula reconstruction of the mandible with condylar removal was performed. Outcomes were determined by maximum interincisal opening, occlusion, and diet after full recovery. Six patients were studied. Two had condylar reconstruction with a contoured fibular head secured to the glenoid fossa. One of them had progressive postoperative trismus and ankylosis. One patient was reconstructed with the native condyle rigidly fixed to the fibula flap, complicated by avascular necrosis requiring condylar resection, with good function afterward. Three patients were left to "hang." All 3 had either normal or improved function after surgery. Two had slight ipsilateral deviation on mouth opening. Function can reliably be reestablished after segmental mandibulectomy and condylectomy with a vascularized fibula flap whose distal end is not precisely contoured or actively seated in the glenoid fossa, as a valid alternative to condylar reconstruction.

Quantitative Analysis of the Effect of Brainstem Shift on Surgical Approaches to Anterolateral Tumors at the Craniovertebral Junction

Many anterolateral craniovertebral junction (CVJ) tumors can safely be resected using a simple posterolateral approach given the surgical corridor provided by brainstem shift. We sought to study how increasing anterolateral CVJ lesion size affects exposure in the posterolateral and far lateral approaches. Six cadaveric heads were used. A posterolateral approach was performed on one side and a far lateral with one-third condyle resection on the other side. Clival and brainstem exposure and surgical freedom were measured. A balloon catheter was used to simulate 10, 15, and 20mm anterolateral mass lesions. Mean clival exposure was significantly greater with the far lateral approach (197.4 versus [vs] 135.0 mm(2), p=0.03) with no balloon, but this difference disappeared with lesion sizes of 10 mm (246.8 vs 237.9 mm(2), p=0.79), 15 mm (306.7 vs 262.4 mm(2), p=0.25), and 20 mm (360.0 vs 332.7 mm(2), p=0.64). Mean brainstem exposure was significantly greater with the far lateral approach for 0 mm (127.8 vs 65.8 mm(2), p<0.01), 10 mm (129.5 vs 87.5 mm(2), p=0.045), and 15 mm (140.1 vs 97.8 mm(2), p=0.01) lesions. There was no difference at 20 mm (146.7 vs 147.8 mm(2), p=0.97). Medial-lateral surgical freedom was greater with the far lateral approach for all sizes. The results of this study provide insight on one important variable in the decision-making process to select the optimal approach for anterolateral CVJ tumors.

Posterior inferior cerebellar artery aneurysms: operative strategies based on a surgical series of 27 patients.

Posterior inferior cerebellar artery (PICA) aneurysms are uncommon. The natural history and management of these aneurysms remains poorly understood. Surgical treatment of PICA aneurysms is challenging in view of their close neurovascular relationship. Data relating to clinical presentation, radiological findings, operative approaches and outcomes were analyzed in 27 consecutive patients surgically treated for PICA aneurysms in a single hospital between January 1991 and December 2010. Headache was the most common presentation (100%) followed by gait ataxia (14.8%) and lower cranial nerve dysfunction (7.4%). SAH was seen in 20 patients, intraventricular hemorrhage in 22 patients, and 3 had evidence of intracerebellar hematoma. Eighteen aneurysms were located proximally and 9 were located distally. The 25 saccular and 2 fusi-saccular aneurysms were secured by direct clipping (24 cases) or aneurysmorrhaphy (3 cases) using a far-lateral suboccipital (without condylar resection) or midline/ paramedian suboccipital approach. Overall outcome at the time of hospital discharge was excellent or good in 88.9% of the patients. PICA aneurysms, by virtue of their rarity and strategic location pose a unique technical challenge. Depending on the PICA segment affected, variations in the surgical corridor and clipping strategy were major contributors to good outcomes.

A two-year audit of non-vascularized iliac crest bone graft for mandibular reconstruction: technique, experience and challenges.

ObjectivesNon-vascularized iliac crest bone graft (NVIBG) is a known treatment option in mandibular reconstruction following jaw resection, but no documented review of patients treated with NVIBG exists for northern Nigeria. The experience and technique from a Nigerian tertiary hospital may serve as baseline data for comparison and improvement of practice for other institutions.Materials and MethodsA retrospective review of medical records and patient case files from January 2012 to December 2013 was undertaken. All case files and other medical records of patients who had reconstruction with NVIBG for benign or malignant lesions with immediate or delayed reconstruction were selected for review.ResultsTwenty patients had mandibular reconstruction with NVIBG during the study period. Two patients were excluded because of incomplete medical records. Eighteen patients' (male=14, female=4) records were reviewed. Their ages ranged from 13 to 62 years (mean 26.0±10.6 years). Indications for NVIBG included jaw tumors (n=16; 88.3%), jaw cyst (n=1; 5.6%) and gunshot injury (n=1; 5.6%). Jaw tumors seen were ameloblastoma (n=15; 83.3%) and osteosarcoma (n=1; 5.6%). Treatments done were mandibular resection with condylar resection (n=7; 38.9%), mandibular segmental resection (n=10; 55.6%) and subtotal mandibulectomy (n=1; 5.6%). Patients' postoperative reviews and radiographs revealed good facial profile and continued bone stability up to 1 year following NVIBG.ConclusionNVIBGs provide an acceptable alternative to vascularized bone grafts, genetically engineered bone, and distraction osteogenesis for mandibular reconstruction in resource-limited centers.

Complete Resection and Immediate Reconstruction With Costochondral Graft for Recurrent Aneurysmal Bone Cyst of the Mandibular Condyle

Aneurysmal bone cyst is a non-neoplastic expansile lesion characterized by replacement with fibro-osseous tissue and blood-filled cavernous spaces. Involvement of the condyle is rare, and only 11 cases have been reported in English-language literature to date. Its common treatment modalities are lesion excision or condylar resection, but recurrence is high in patients treated with the former. The authors reported a 19-year-old female patient with swelling of the right preauricular region, who had a surgical curettage history in another hospital. The lesion was completely resected and the jaw was immediately reconstructed with costochondral graft with the help of SurgiCase software. The patient has been symptom-free for 6 months postoperatively.

Surgical treatment of hyperplasia and osteochondroma of the mandibular condyle: a long-term follow-up study

Background and objectives: Hyperplasia and osteochondroma of the mandibular condyle are both rare conditions. In the adult, surgical treatment is the same for both conditions: resection of the mandibular condyle and mandibular osteotomy. Rarely, maxillary osteotomy is necessary. We have previously published on a surgical method that avoids autogenic grafts or joint prosthesis. The objective of this study is to present a long-term clinical follow-up of 8 patients.

Quantitative analysis of the effect of brainstem shift on surgical approaches to anterolateral tumors at the craniovertebral junction

Many anterolateral craniovertebral junction (CVJ) tumors can safely be resected using a simple posterolateral approach given the surgical corridor provided by brainstem shift. We sought to study how increasing anterolateral CVJ lesion size affects exposure in the posterolateral and far lateral approaches. Six cadaveric heads were used. A posterolateral approach was performed on one side and a far lateral with one-third condyle resection on the other side. Clival and brainstem exposure and surgical freedom were measured. A balloon catheter was used to simulate 10, 15, and 20mm anterolateral mass lesions. Mean clival exposure was significantly greater with the far lateral approach (197.4 versus [vs] 135.0 mm(2), p=0.03) with no balloon, but this difference disappeared with lesion sizes of 10 mm (246.8 vs 237.9 mm(2), p=0.79), 15 mm (306.7 vs 262.4 mm(2), p=0.25), and 20 mm (360.0 vs 332.7 mm(2), p=0.64). Mean brainstem exposure was significantly greater with the far lateral approach for 0 mm (127.8 vs 65.8 mm(2), p<0.01), 10 mm (129.5 vs 87.5 mm(2), p=0.045), and 15 mm (140.1 vs 97.8 mm(2), p=0.01) lesions. There was no difference at 20 mm (146.7 vs 147.8 mm(2), p=0.97). Medial-lateral surgical freedom was greater with the far lateral approach for all sizes. The results of this study provide insight on one important variable in the decision-making process to select the optimal approach for anterolateral CVJ tumors.