A novel animal model of underactive bladder: analysis of lower urinary tract function in a rat lumbar canal stenosis model.

AIMS: An animal model of neurogenic underactive bladder (UAB) has not been established. It was reported that a rat lumbar spinal canal stenosis (LCS) model created by cauda equina compression manifested intermittent claudication and allodynia. In this study, we examined the lower urinary tract function of the rat LCS model. METHODS: One small hole was drilled at the fifth lumbar vertebral arch (sham), and a rectangular piece of silicone rubber was inserted into the L5-L6 epidural space (LCS). Before and after surgery, a metabolic cage study was performed. After surgery, awake cystometry (CMG) and an in vitro muscle strip study were performed. Bladder morphology was evaluated by hematoxylin and eosin staining. RESULTS: The LCS rats showed a significant decrease in voided volume and a significant increase in postvoid residual volume and residual urine rate compared with Sham rats. CMG showed that the postvoid residual urine volume and numbers of non-voiding contractions significantly increased, while the voided volume, threshold pressure, and maximum intravesical pressure during voiding significantly decreased. There were no significant differences between sham and LCS rats in response to carbachol. In contrast, there was a significant increase in response to field stimulation, especially at lower frequencies, in LCS rats. LCS rats showed no obvious difference in detrusor morphology. CONCLUSIONS: This rat model requires a relatively simple surgical procedure and has characteristics of neurogenic UAB. It seems to be useful in the pathophysiological elucidation of UAB and might have potential for assessment of pharmacotherapy of UAB.

The presence of mandibular third molars during sagittal split osteotomies does not increase the risk of complications.

PURPOSE: The purpose of this study was to investigate prospectively the effects of the presence or absence of third molars during sagittal split osteotomies (SSOs) on the frequency of unfavorable fractures, degree of entrapment and manipulation of the inferior alveolar nerve (IAN), and procedural time. MATERIALS AND METHODS: The investigators designed and implemented a prospective cohort study and enrolled a sample composed of patients who underwent SSOs to correct mandibular deformities. The primary predictor variable was the status of the mandibular third molar at the time of SSO, and it was divided into 2 levels, present at the time of SSO (group I) or absent at the time of SSO (group II). The primary outcome variable was unfavorable splits. The secondary outcome variables were the degree of entrapment/manipulation of the IAN and the procedural time. Appropriate bivariate and multivariate statistics were computed, and the level of statistical significance was set at P < .05. RESULTS: Six hundred seventy-seven SSOs were performed in 339 patients: group I consisted of 331 SSOs (mean age ± SD: 19.6 ± 7.4 yrs), and group II consisted of 346 SSOs (30.4 ± 12.1 yrs). The overall rate of unfavorable fractures was 3.1% (21 of 677), with frequencies of 2.4% (8 of 331) in group I, compared with 3.8% (13 of 346) in group II (P = .3). The rate of IAN entrapment in the proximal segment was significantly lower in group I (37.2%) than in group II (46.5%; P = .01). The degree of entrapment was also significantly more severe for group II (P < .001). Third molars increased procedural time by 1.7 minutes (P < .001). CONCLUSIONS: The presence of third molars during SSOs is not associated with an increased frequency of unfavorable fractures. Concomitant third molar removal in SSOs also decreases proximal segment IAN entrapment but only slightly increases operating time.

Concomitant removal of mandibular third molars during sagittal split osteotomy minimizes neurosensory dysfunction.

PURPOSE: Inferior alveolar nerve (IAN) injury is 1 of the most important postoperative complications after sagittal split osteotomy (SSO). The purpose of our study was to investigate the effects of the presence or absence of a mandibular third molar on the neurosensory recovery of the IAN after SSO. MATERIALS AND METHODS: A prospective cohort study enrolled a sample composed of patients who underwent SSO to correct mandibular deformities. The primary predictor variable was the status of the mandibular third molar at the time of SSO and it was divided into two levels, present at the time of SSO (Group I) or absent at the time of SSO (Group II). The primary outcome variable was neurosensory recovery of the IAN, assessed using the Medical Research Council scale, functional sensory recovery, and subjective evaluation. Neurosensory status was measured 3 times (preoperatively and 3 and 6 months postoperatively). Appropriate bivariate and multivariate statistics were computed, and the level of statistical significance was set at P < .05. RESULTS: A total of 120 SSOs were performed in 60 patients. Group I included 64 SSOs (mean patient age ± SD 19.3 ± 8.0 years) and group II, 56 SSOs (mean patient age 24.9 ± 10.0 years). The Medical Research Council scale scores showed that the presence of third molars during SSO was associated with a statistically significant decreased incidence of neurosensory disturbance of the IAN at 3 and 6 months postoperatively (all P < .01). Functional sensory recovery was achieved more frequently in group I, but this difference remained significant only at 3 months after adjusting (P = .01). A "normal sensation" was subjectively reported more frequently in group I at 3 and 6 months postoperatively (P ≤ .05). CONCLUSIONS: The presence of third molars during SSO minimizes postoperative neurosensory disturbance of the IAN.

[State of lower alveolar and mental nerves by mandible fractures healing under transbone osteosynthesis].

Fracture of mandibular body at the level of P3-P4 with symphysis rupture was modeled, reposition and transosseous osteosynthesis with a specially developed device were performed under anesthesia in the operating room in 17 adult mongrel dogs in order to specify the pathogenesis and the dynamics of injury and jaw nerve regeneration. It has been established, that the arrangement of the neurovascular bundle in medullary canal predetermines the development of acute and chronic compression-and-ischemic neuropathy even if accurate reposition of bone fragments takes place. The histological signs of nerve fiber regeneration, the loss of the quantity of myelin-free nerve conductors and the retrograde spreading of degenerative changes in myelinized nerve conductors, including regenerating ones, have been found beginning from 4 weeks after injury. It has been concluded, that spontaneous nerve regeneration in case of mandibular fractures should be actively supported by neuroprotective, anti-edematous and anti-inflammatory therapy.

Differential diagnosis of endodontic-related inferior alveolar nerve paraesthesia with cone beam computed tomography: a case report.

AIM: To discuss the use of cone-beam computed tomography (CBCT) in the differential diagnosis of a case of labiomandibular paraesthesia caused by extrusion of endodontic sealer into the mandibular canal. SUMMARY: A 59-year-old woman suffering from a paraesthesia on the left posterior mandible and numbness on the left side of the lower lip was referred to an endodontic specialist 1 month after multiple root canal treatments. A panoramic radiograph revealed the presence of extruded root filling material beyond the apex of the mesial root of the mandibular left second molar and also beyond the apex of the first premolar. A cone beam computed tomography examination was undertaken, which confirmed the presence of radiopaque root canal filling material in the periapical area of the second molar, and revealed that the material was inside the mandibular canal. No extruded filling material was found inside the mental foramen beyond the apex of the first premolar tooth. KEY LEARNING POINTS: Small field of view CBCT (where possible) can be considered an effective radiographic diagnostic device when endodontic-related inferior alveolar nerve or mental foramen paraesthesia are suspected. CBCT is able to provide detailed three-dimensional images of the tooth, the root canal system and the surrounding tissue.

Femoral nerve compression after migration of bone cement to the groin after hip arthroplasty.

Although often a benign complication of total hip arthroplasty, cement extrusion can cause nerve, vessel, and organ compression. We report the case of a 70-year-old male patient in whom an extruded cement mass migrated anteriorly and compressed the femoral nerve and impinged on the femoral artery producing acute, severe groin pain with neuralgia 9 years postoperatively. Paresthesia of the anterior and medial thigh was found on examination. Radiographic, ultrasound, and computed tomographic studies confirmed a 6 × 1.5-cm mass of bone cement in the right groin compressing the femoral nerve that was removed successfully at surgery. Six months postoperatively, the patient's pain had resolved, but hyperesthesia of the medial thigh remained.

Decompression of inferior alveolar nerve: case report.

Paresthesia as a result of mechanical trauma is one of the most frequent sensory disturbances of the inferior alveolar nerve. This case report describes surgical treatment for paresthesia caused by a compressive phenomenon within the mandibular canal. The cause of the compression, a broken instrument left in the patient's mouth during previous endodontic therapy, was identified during routine radiography and computed tomography. Once the foreign object was removed by surgery, the paresthesia resolved quickly. This case highlights the potential for an iatrogenic mechanical cause of paresthesia.

Facial nerve palsy after sagittal split ramus osteotomy of the mandible: mechanism and outcomes.

PURPOSE: Facial nerve palsy after sagittal split ramus osteotomy of the mandible (SSRO) is a rare, but serious, complication. The aim of the present study was to evaluate the incidence of this complication, the possible causative mechanisms, its subsequent management, and eventual outcomes. PATIENTS AND METHODS: All patients who underwent SSRO of the mandible at the Craniofacial Center, Chang Gung Memorial Hospital, Taiwan, from 1981 to 2008 were included in the present study. The patients reported as having postoperative facial nerve paralysis were identified and reviewed. RESULTS: A total of 3,105 patients had undergone bilateral SSRO (6,210 sagittal splits). Of these 3,105 patients, 6 were reported as having unilateral facial nerve palsy postoperatively, for an incidence of 0.1%. One case was diagnosed as Bell's palsy. None of the patients with postoperative facial nerve palsy required surgical intervention, but all received physical therapy and medications. Complete recovery was obtained without sequela in all but 1 patient, who had incomplete frontal branch recovery. CONCLUSIONS: Most facial nerve palsies that occur after SSRO of the mandible result from neurapraxia or axonotmesis, possibly from nerve compression or traction. Complete recovery can be expected in most cases, and conservative management without surgical exploration is recommended.

Tibial nerve impingement secondary to posterior cement extrusion after unicompartmental knee arthroplasty.

Unicompartmental knee replacements have become increasingly popular with improved survivorship and clinical results. This has been combined with minimally invasive surgery to further improve patient recovery and rehabilitation. Despite improved instrumentation, it remains a technically demanding procedure. We present a previously unreported case of tibial nerve impingement as a consequence of posterior cement extrusion after a unicompartmental knee replacement.

Trigeminal impingement syndrome: the relationship between atypical trigeminal symptoms and anteromedial disk displacement.

The purpose of this study was to determine if compression of the mandibular nerve and its branches could be caused by antero-medial disk displacement, resulting in atypical facial pain. Sixteen temporomandibular joints (TMJ) were dissected and injected with an autopolymerizing solution into the superior compartment, which produced an artificial capsular swelling that caused disk displacement. In all specimens, the TMJ capsule was close to the mandibular branch of the trigeminal nerve after the intracapsular injection. Thus, capsular distension or antero-medial disk displacement, as seen in various temporomandibular disorders (TMD), could result in nerve compression and facial pain symptoms.

Hypoglossal Nerve: Anatomy, Anatomical Variations Comorbidities and Clinical Significance.

We review the anatomical variations of the hypoglossal nerve and their surgical and clinical significance, and we report multiple diseases that affect function of the nerve leading to paresis, either unilateral or bilateral. The hypoglossal nerve is the 12th cranial nerve, and knowledge of the detailed anatomy and relationship with critical structures is of paramount importance in neurosurgery, head and neck surgery, and vascular surgery. Numerous studies have depicted conventional landmarks in the cervical part of the hypoglossal nerve, but their findings have not been consistent reliable. We analyze and review these critical landmarks used to identify and preserve the hypoglossal nerve during surgery and to minimize iatrogenic complications in head and neck, neurosurgical, and vascular procedures. We performed an online database search during January and February 2019 to pinpoint the diseases that affect function of the nerve. According to this literature review, apart from iatrogenic injury during surgery, the most frequently observed cause of paresis is pressure due to the presence of tumours and head injury. Furthermore, motor neuron degenerative conditions, such as amyotrophic lateral sclerosis, multiple sclerosis or tooth infection and presence of an aberrant vessel in the hypoglossal canal can affect the function of the nerve.

Trigeminal Neuralgia Due to Petrosal Bone Deformity.

BACKGROUND: There have been a few previous reports of trigeminal neuralgia caused by bony structures. We report a rare case of trigeminal neuralgia caused by petrous bone deformity. CASE DESCRIPTION: A-43-year-old man with facial pain in the left maxillary and mandibular divisions of the trigeminal nerve was referred to our hospital. Computed tomography showed bone hyperplasia protruding into the left cerebellopontine cistern, compressing the left trigeminal nerve. Administration of carbamazepine ameliorated facial pain, but the effect was unsatisfactory, and microvascular decompression was performed through the anterior transpetrosal approach. The protruding petrous bone was drilled out to release compression of the trigeminal nerve, thus straightening the deviated trajectory of the nerve. The superior cerebellar artery adjacent to the thickened petrosal bone seemed to have compressed the trigeminal nerve and was also transposed. The facial pain disappeared completely after microvascular decompression surgery. CONCLUSIONS: The anterior transpetrosal approach is an appropriate and essential strategy for trigeminal neuralgia caused by petrous bone deformity of the petrous apex.

Case report : recurrent piriformis syndrome after surgical release.

Piriformis syndrome is an uncommon condition characterized by sciatic nerve entrapment at the greater sciatic notch. Nonoperative treatment such as physical therapy, nonsteroidal antiinflammatory drugs, and local injections often results in relief of symptoms. For patients who do not benefit from nonoperative therapy, surgical exploration and decompression of the sciatic nerve has been effective. However, the success of surgery may be diminished by scar formation or hematoma in the anatomically restricted sciatic notch. We report two patients with piriformis syndrome who responded primarily to surgical decompression and had recurrent symptoms resulting from scar tissue formation in the sciatic notch. On revision surgery, polytetrafluoroethylene pledgets were placed around the sciatic nerve to avoid compression and entrapment by scar tissue. Both patients had satisfactory outcomes at 3 years followup.

Asymptomatic hypoesthesia of the maxillary alveolar ridge in complete denture wearers.

This study was carried out to investigate the effect of compression induced by complete dentures on the function of the nerves underlying the dentures. The influence of compression induced by complete dentures on nerve function was analysed using current perception threshold (CPT) in 33 complete denture wearers aged 50-80 at Nihon University School of Dentistry (Matsudo, Japan). Based on the age range of the complete denture group, dentate subjects were selected as a control. Because the group characteristics (such as subject age, gender, body mass index) and oral mucosal thickness were not matched, a multiple regression analysis was used to adjust for the influence of heterogeneous characteristics on the CPT. Statistically significant differences were found between subject groups for the nasopalatine and the greater palatine nerve. The results of the study were that complete denture wearers experience asymptomatic hypoesthesia mainly affecting the nasopalatine and greater palatine nerves, but not the infraorbital nerve.

Femoral nerve palsy after mandibular reconstruction with microvascular iliac flap: a complication under anticoagulation therapy.

Pharmacological prophylaxis and intervention are used extensively in head and neck reconstructions with microvascular flaps. There is no universally accepted protocol, but the microvascular surgery literature recommends intraoperative anticoagulation with heparin. Here is reported a case of iliacus haematoma with subsequent femoral nerve palsy after the harvest of a microvascular iliac flap for mandibular reconstruction in a patient who had been treated with heparin. The association between femoral nerve palsy and anticoagulant therapy has been well described. It remains unclear as to why the iliacus muscle is particularly vulnerable to intramuscular haemorrhage. Femoral nerve neuropathy is also an uncommon but recognized complication after abdominopelvic surgery. Iliacus haematoma secondary to microvascular surgery has not been previously reported. This case illustrates the need to be aware of this type of complication and its clinical manifestations for patients under anticoagulant therapy in the perioperative period during microvascular reconstructions.

Ossified pterygospinous ligament and its clinical implications.

OBJECTIVE: To study the anatomico-radiological aspects of ossified pterygospinous ligament in human skulls. BACKGROUND: The pterygospinous ligament is usually attached to spine of the sphenoid and the posterior border of the lateral pterygoid plate. It may sometimes be ossified. MATERIALS AND METHODS: The lateral pterygoid plate of the sphenoid bone and the presence of ossified pterygospinous ligament was studied in 50 dried bone specimens and photographed. A skiagram of the ossified pterygosphenoid ligament was also obtained. RESULTS: Out of 50 specimens studied, we observed the presence of flattened and broad lateral pterygoid plate and incomplete, ossified, pterygospinous ligament on the right side, in only one bone specimen. The lateral pterygoid was as usual thin, broad and everted in the other 49 specimens. CONCLUSION: The study describes anatomical and radiological aspects of an incomplete ossified pterygospinous ligament. The presence of ossified pterygospinous ligament may result in the formation of a foramen, through which the branches of mandibular nerve may pass. Presence of such anomalies may compress upon the branches of the mandibular nerve and chorda tympani nerves. Increase in the width and flattening of the lateral pterygoid plate may leave little space, causing difficulty while performing surgical operations on the pterygoid region. Anomalies involving the pterygospinous ligament may not only be of academic interest but also be beneficial for maxillofacial and dental surgeons and anaesthetists (Fig. 3, Ref. 11).

[Long Term Complications Due to Polyethylene Wear in Total Knee Arthroplasty: a Case Report]. / Langzeitkomplikationen durch Polyethylenabrieb bei Knietotalendoprothese: ein Fallbericht.

This is the case of an 84-year-old patient 18 years after total knee replacement. Regular follow-up examinations did not take place beyond 10 years of implantation, so that subsequent wear of the polyethylene insert was not detected. The patient presented because of knee pain, swelling of the calf, and a drop foot. Examination showed a large ganglion with pressure on the peroneal nerve, and a loose knee replacement with severe inlay wear and extensive osteolysis around the tibial and femoral implants. This rare case demonstrates the importance of regular clinical and radiological follow-up examinations after total joint replacements, particularly in the long term.