Unusual orthopedic manifestations of neurofibromatosis.

Forty-four children with neurofibromatosis were found to have three previously underdescribed conditions: thoracic lordoscoliosis, protrusio acetabuli, and monomelia neurofibromatosis. Thirty-four patients (77%) had scoliosis; of these, nine had dystrophic scoliosis (Group I, 26%), six had dystrophic lordoscoliosis (Group II, 18%), eight had dystrophic kyphoscoliosis (Group III, 24%), and 11 had nondystrophic scoliosis (Group IV, 32%). Group III curves were severe and progressive, rendering them difficult to stabilize even with anterior and posterior spinal fusions. Group II curves were progressive but stabilized by posterior spinal fusion alone. Group I curves were less progressive than Groups II and III, but required surgery more often than those of Group IV, which were generally controlled by orthoses. Protrusio acetabuli of varying severity occurred in 13 patients (21 hips). Three patients had involvement of a single limb (monomelic neurofibromatosis).     

The relationship between tears of the peroneus brevis tendon and the distal extent of its muscle belly: an MRI study

BACKGROUND: Anomalous distal insertion of the peroneus brevis muscle belly has been implicated as a possible etiology of tears of the peroneus brevis tendon. The purpose of this study was to assess whether patients with operatively confirmed tears of the peroneus brevis tendons have a more distally located musculotendinous junction. METHODS: A retrospective review was done to identify all patients in whom direct inspection of the peroneal tendons was done between 1999 and 2004. The operative reports were evaluated, and all in whom a peroneal tendon tear was confirmed were included in the study group, Group I (29 patients). Group II represented an operative control group and consisted of all patients who had operative inspection of the peroneal tendons but did not have a tear (30 patients). Group III represented a radiographic control group and consisted of patients who had MRI of the ankle for reasons unrelated to lateral ankle symptoms (30 patients). For each patient, the vertical distance from the musculotendinous junction of the peroneus brevis tendon to the tip of the fibula was measured on sagittal MRI. The role of gender also was examined. The average distance between the musculotendinous junction of the peroneus brevis tendon to the distal fibula was calculated solely for men and women in all three groups. Statistical comparison of the groups was performed using the Mann-Whitney test. Interobserver reliability was determined by calculating Cronbach's Alpha coefficient. RESULTS: The average distance from the musculotendinous junction to the tip of the fibula was 33.1 cm, 41.2 cm, and 46.3 cm in Groups I, II, and III, respectively. The average distance in Group I was statistically significantly lower than the average distance in both Groups II and III (p < 0.05). Interestingly, the difference in the distance between Groups II and III also was statistically significant (p < 0.05). The average distances in both men and women were statistically significantly different (p < 0.05) among the three groups. CONCLUSION: It has been hypothesized that tears of the peroneus brevis tendon result from distal insertion of the peroneus brevis muscle belly. This study provides radiographic support for this hypothesis.     

Scoliosis induced by anterior and posterior rhizotomy

This paper presents the result and statistical analysis of an experiment in which selective anterior or posterior rhizotomy was carried out under microscopic surgery. The animals used for the experiment were 48 young rabbits, and they were divided into four groups. Group 1, which was used as control, was subjected to lower dorsal bilateral laminectomies with dural incision; Group II to laminectomies with three right posterior rhizotomies; Group III to laminectomies with three right anterior rhizotomies, and Group IV to laminectomies with three right anterior and posterior rhizotomies. Scoliosis was induced in Groups II, III, and IV. There was no significant statistical difference in the degree of curvatures among these three groups. The convexity of the curvature faced to the side of the divided roots. In Groups III and IV, scoliotic curvatures were obvious within 2 weeks, but there were no considerable changes thereafter. In Group II, the curves progressed slowly up to the 12th week. They were statistically significant at the fourth week and increased continuously thereafter. The histologic findings in Groups III and IV showed denervation atrophy of the paravertebral muscles at the apex of the curvature, but there was little or no muscle atrophy in Groups I and II. The experimental results indicate that scoliosis may be induced not only by anterior root paralysis but also by selective posterior root paralysis.     

Treatment of stage I posterior tibial tendon dysfunction with medial soft tissue procedures

Seven patients with Stage I posterior tibial tendon dysfunction were treated with synovectomy, with or without tendon debridement. At the 11-month followup, six patients were completely pain free. The one patient who eventually required flexor digitorum longus transfer and lateral column lengthening because of progression to Stage II disease had significant intrasubstance tendinous degeneration. Early diagnosis and aggressive treatment are imperative to prevent progression of Stage I posterior tibial tendon dysfunction. Operative treatment is indicated if a reasonable trial of casting or bracing does not relieve symptoms.     

The primary action of epidural fentanyl after cesarean delivery is via a spinal mechanism

We tested the hypotheses that the primary mechanism of action of epidural fentanyl after cesarean delivery is spinal and that very small dose epidural bupivacaine with epinephrine enhances this effect. After elective cesarean delivery, 100 parturients were randomized in a double-blinded design to four groups. Group I and II patients received a continuous 12 mL/h epidural infusion of bupivacaine 0.015% with epinephrine 1 microg/mL for 48 h and Groups III and IV received a 12 mL/h saline epidural infusion instead. Fentanyl 20 microg/mL was administered via a patient-controlled analgesia device either into the epidural infusion (Groups I and IV) or IV (Groups II and III). When compared to patients receiving epidural fentanyl, those receiving IV fentanyl required larger mean infused and total dose of fentanyl (P < 0.0001), reported more pain (P < 0.001), and had a more frequent incidence of excessive sedation (P < 0.01), nausea (P < 0.01), and vomiting (P < 0.01). Plasma concentrations of fentanyl were larger for Group II and III than for Groups I and IV (P < 0.001) at 24 and 48 h. Our results support the hypothesis that the primary mechanism of analgesia of epidural fentanyl after cesarean delivery is spinal. Our data also show that the total required dose of epidural, but not IV, fentanyl is reduced by very small dose epidural bupivacaine and epinephrine (Group I versus Group IV, P < 0.02 and Group II vs Group III, not significant). IMPLICATIONS: Fentanyl administered epidurally to parturients after cesarean delivery has a primarily spinal mechanism of action and this effect is enhanced by very small dose epidural bupivacaine and epinephrine.     

Rapid induction sequence with vecuronium: should we intubate after 60 or 90 seconds?

The purpose of the study was to determine intubating conditions after administration of either succinylcholine or vecuronium in a rapid induction sequence. Patients received either succinylcholine 1.5 mg.kg-1 (Groups I and II) after d-tubocurarine 0.05 mg.kg-1 four minutes earlier, or vecuronium (Groups III and IV) in an initial dose of 0.01 mg.kg-1 followed four minutes later by 0.1 mg.kg-1. In Groups I and III an apnoeic delay of one minute was allowed before intubation whereas in Groups II and IV the delay was 90 sec. There was no significant difference in intubating conditions between Groups I and IV. Intubating conditions in Group III (vecuronium-delay of one minute) were statistically worse than in any of the three other groups. A delay of 90 sec after succinylcholine improved intubating conditions in male patients. Considering that intubating conditions obtained after 90 sec in patients given a priming sequence with vecuronium (Group IV) were not different from those obtained 60 sec after succinylcholine (Group I), the authors conclude that vecuronium is an acceptable alternative for rapid tracheal intubation. In the doses used in this study, intubating conditions 60 sec after vecuronium were unacceptable for rapid induction of anaesthesia.     

Arthroscopic Changes of the Biceps Pulley in Rotator Cuff Tear and Its Clinical Significance in Relation to Treatment

Background

In the case of rotator cuff tears, the biceps pulley can be stressed by the unstable biceps tendon, and this can subsequently affect the stability of the subscapularis tendon. Therefore, it is important to distinguish between normal variations and lesions of the biceps pulley that affect anterosuperior lesions in cases of rotator cuff tears.

Methods

From January 2002 through November 2010, we observed biceps pulley and associated anterosuperior lesions in 589 of 634 cases (93%) of arthroscopic rotator cuff repair, including 72 cases (12.2%) of small tears, 219 cases (37.2%) of medium tears, 134 cases (22.8%) of large tears, and 164 cases (27.8%) of massive tears. We classified normal stretched biceps pulleys as type I, stretched biceps pulleys with mild changes as type II, those with a partial tear as type III, and torn pulleys as type IV.

Results

We were able to classify 589 cases of biceps pulleys as type I, II, III, or IV associated lesions in rotator cuff tears. Type I was seen in 91 cases (15.4%), type II in 216 cases (36.7%), type III in 157 cases (26.7%), and type IV in 101 cases (17.1%); unidentified cases numbered 24 (4.1%). Nearly three-quarters, 73.3%, of the cases (432/589) had associated anterosuperior lesions, and combined treatment for the associated lesions was administered in 29.2% (172/589) of cases.

Conclusions

Biceps pulley lesions with more than partial tears were identified in 48% of rotator cuff tear cases. The incidence and severity of pulley lesions were related to the rotator cuff tear size, the status of the long head of the biceps tendon and subscapularis tendon lesion, and the treatment methods.     

Effects of oral clonidine premedication on concentrations of Cortisol and monoamine neurotransmitters and their metabolites in cerebrospinal fluid and plasma

Forty-two healthy male patients (aged 19-40 years), undergoing orthopaedic surgery under spinal anaesthesia (3 ml isobaric 0.5% bupivacaine), were given clonidine 4.5 micrograms kg-1 orally either 2 (Group I, n = 10) or 4 (Group II, n = 10) hours before the operation, diazepam 0.15 mg kg-1 orally (Group III, n = 10) or a placebo tablet (Group IV, n = 12) 2 h before the operation. Plasma concentrations of cortisol, noradrenaline (NA), adrenaline (A), 3,4-dihydroxyphenylglycol (DHPG) and dihydroxyphenylacetic acid (DOPAC) were assayed from venous blood samples just before premedication and just before the spinal block. Cerebrospinal fluid (CSF) concentrations of cortisol, tryptophan, 5-hydroxyindoleacetic acid and catecholamine metabolites were assayed from a sample taken before the spinal block. The plasma NA concentrations of the patients in the groups receiving clonidine decreased clearly compared with the other groups (P less than 0.05). The NA metabolite DHPG was also lower in Groups I and II than in Group III (P less than 0.05) after premedication. Plasma A concentrations were lower in Groups I and III than in Group IV (P less than 0.05). The CSF concentrations of the different substances were similar in all groups. In Group I the sensory blockade lasted significantly longer than in Group III (P less than 0.05) and the mean duration of motor blockade was longer in Group I than in Groups III and IV (P less than 0.05). Two patients in both clonidine groups developed bradycardia (heart rate less than 45 min-1) requiring atropine treatment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Lateral Column Lengthening for Acquired Adult Flatfoot Deformity Caused by Posterior Tibial Tendon Dysfunction Stage II: A Retrospective Comparison of Calcaneus Osteotomy with Calcaneocuboid Distraction Arthrodesis

In this study, clinical and radiological results after lateral column lengthening by calcaneocuboid distraction arthrodesis and calcaneus osteotomy were compared. Thirty-three patients (35 feet) treated with lateral column lengthening by distraction arthrodesis (14 patients, 16 feet; group I) or by calcaneus osteotomy (19 patients, 19 feet; group II) for adult-acquired flatfoot deformity caused by stage II posterior tibial tendon dysfunction were compared retrospectively. Mean follow-up was 42.4 months (range, 6-78 months) for group I and 15.8 months (range, 6-32 months) for group II (P < .001). The American Orthopaedic Foot & Ankle Society ankle-hindfoot score was determined, 4 variables were measured on preoperative and postoperative weight-bearing radiographs, and a number of independent and outcome variables, including patient satisfaction, were recorded. Group 2 had a significantly higher American Orthopaedic Foot & Ankle Society score compared with group I (mean, 85 vs. 72, respectively; P < .02) at time of last follow-up, and there were no dissatisfied patients in group I, whereas 2 patients in group II were dissatisfied with the result of the operation. All radiological results were significantly better at time of follow-up in both groups (except for talocalcaneal angle in group I), although no significant differences were noted in the amount of change in radiographic measurements between the groups. No significant correlation was found between follow-up time and radiographic improvement, indicating stable radiographic measurements over time. In group II, 13 mild calcaneocuboid subluxations were observed. In both groups, 1 nonunion and 1 wound complication occurred. Based on our experience with the patients described in this report, we recommend lateral column lengthening by means of calcaneus osteotomy rather than distraction arthrodesis of the calcaneocuboid joint, for correction of stage II posterior tibial tendon dysfunction.     

Retinal artery pressure and cerebral artery perfusion pressure in cerebrovascular occlusive disease

The objectives of the investigation were to measure the retinal artery pressure (RAP) and cortical artery pressure (CAP) in patients undergoing superficial temporal artery to middle cerebral artery (STA-MCA) bypass, to study the relationship between these pressures, and to evaluate our ability to predict CAP on the basis of RAP. The 44 patients undergoing bypass surgery included 26 with ipsilateral internal carotid artery (ICA) occlusion (Group I), 5 with bilateral ICA occlusion (Group II), 4 with inaccessible ICA stenosis proximal to the ophthalmic artery (OA) (Group III), 2 with ICA stenosis distal to the OA (Group IV), 3 with ICA occlusion distal to the OA (Group V), 2 with MCA stenosis (Group VI), and 2 with MCA occlusion (Group VII). Five patients undergoing craniotomy for an asymptomatic saccular aneurysm were used as controls. Mean RAP (MRAP) was measured by ophthalmodynamometry (ODM) and was expressed as a ratio of the mean systemic arterial blood pressure (i.e., MRAP/MSAP). The mean MRAP/MSAP for combined Groups I, II, and III with ICA occlusion proximal to the OA was significantly lower than both the control group (P = 0.0001) and the combined Groups IV, V, VI, and VII with occlusive lesions distal to the OA (P = 0.0001). Six patients in Groups I and II with venous stasis retinopathy had a mean MRAP/MSAP of 0.18 +/- 0.11. Mean cortical artery pressure (MCAP) was measured by inserting a 26 gauge needle into a small cortical artery and was expressed as the MCAP/MSAP ratio. Mean MCAP/MSAP was less than 0.50 for all groups except Group III.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effect of intravenous pantoprazole and ranitidine for improving preoperative gastric fluid properties in adults undergoing elective surgery

We studied pantoprazole, a new potent and fast-acting proton pump inhibitor. Its effects on preoperative gastric fluid volume and pH have not yet been determined. In this randomized, controlled trial, we examined the effects of preoperative IV pantoprazole or ranitidine on gastric pH and volume. Ninety patients (ASA status I and II, scheduled for elective surgery) were studied. One hour before surgery, patients in Group I (n = 30) were given IV saline 5 mL, those in Group II (n = 30) were given 40 mg of pantoprazole IV, and those in Group III (n = 30) were given 50 mg of ranitidine IV. A nasogastric tube was inserted immediately after anesthesia induction. Gastric contents were aspirated, and volume and pH were recorded. The pH values determined in Group I were 3.73 +/- 0.82; in Group II, they were 5.30 +/- 1.84; and in Group III, they were 4.80 +/- 1.40. There was no statistical difference between Groups 2 and 3, but there was a significant difference between Group I and Groups 2 and 3 (P < 0.0005). The volume of the gastric contents was 28.67 +/- 10.98 mL in Group I, 15.20 +/- 15.52 mL in Group II, and 7.77 +/- 11.17 mL in Group III. There was no statistical difference between Groups 2 and 3, but there was a statistically significant difference between Group I and Groups 2 and 3 (P < 0.0005). The proportion of patients considered "at risk" of significant lung injury should aspiration occur was 20% of Group I, 10% of Group II, and 3.3% of Group III. When statistically evaluated, there was no difference among groups. We concluded that the administration of IV pantoprazole and ranitidine 1 h before surgery is effective in reducing gastric pH and volume. IMPLICATIONS: This randomized, controlled trial examined the effects of preoperative IV pantoprazole or ranitidine on gastric pH and volume. We concluded that IV pantoprazole and ranitidine, given 1 h before surgery, are effective in reducing gastric pH and volume.     

The effect of dilution and prolonged injection time on fentanyl-induced coughing

This study was designed to evaluate the effect of diluting fentanyl 50 microg x ml(-1) to 25 or 10 microg x ml(-1) with 0.9% saline and prolonged injection time on fentanyl-induced cough. Two hundred patients requiring general anaesthesia were randomly allocated into four groups: 50 microg x ml(-1) (Group I), 25 microg x ml(-1) (Group II), 10 microg x ml(-1) (Group III) or 10 microg x ml(-1) combined with prolonged injection (Group IV). Fentanyl 3 microg x kg(-1) was administered within 5 s in Groups I, II, and III, or over 30 s in Group IV. Occurrence of cough was significantly reduced in Group IV (2% vs 32%, 16% and 12% in Groups I, II and III, respectively, p < 0.05). There were no statistically significant differences in the severity of coughing between the four groups (p > 0.05). We conclude that dilution of fentanyl to 10 microg x ml(-1) with 0.9% saline combined with a prolonged injection time eliminates fentanyl-induced cough.     

Changes in collagen matrix composition in human posterior tibial tendon dysfunction

OBJECTIVE: To investigate whether tendon degeneration in posterior tibial tendon dysfunction syndrome is associated with changes in extracellular matrix collagen composition. METHODS: Specimens from grossly abnormal tendon regions from 9 patients with posterior tibial tendon dysfunction syndrome were prepared for routine histology. Collagens I, III and V were typed by immunoblotting and quantified by densitometry after SDS-PAGE. Proline and hydroxyproline residues were determined by liquid chromatography. Four other samples from grossly normal homologous tendon regions and one surgical specimen from a healthy patient undergoing arthrodesis of the ankle after an accident were included as control. RESULTS: In the grossly abnormal surgical posterior tibial tendon specimens we observed three types of histopathologic conditions present to varying degrees: increased mucin content, fibroblast hypercellularity and neovascularization. Analysis of degenerate tendons demonstrated a 79.3% increase in total proline and a 32.4% increase in 4-hydroxyproline. In addition, damaged tissue contained a higher proportion of collagen type III (mean increase: 53.6%) associated with a concomitant increase in type V collagen (mean increase: 26.4%). These alterations were accompanied by a reduction in type I collagen (mean decrease: 41.4%). CONCLUSIONS: In posterior tibial tendon dysfunction syndrome, the degenerative process results from marked changes in both structural organization and molecular composition of matrix collagens. The higher proportion of type V and type IlI collagens in degenerated tendons is likely to contribute to a decrease in the mechanical resistance of the tissue.     

Effects of combined administration of transforming growth factor-beta1 and epidermal growth factor on properties of the in situ frozen anterior cruciate ligament in rabbits.

The mechanical properties of tendon autografts used in reconstruction of the anterior cruciate ligament (ACL) are reduced after surgery. Previous studies showed that growth factors such as transforming growth factor-beta1 (TGF-beta1) and epidermal growth factor (EGF) can stimulate fibroblast proliferation and increase collagen and noncollagenous protein synthesis by these cells. These factors might be useful, therefore, in preventing graft deterioration after transplantation or accelerating mechanical restoration of the deteriorated graft. The purpose of our study, therefore, was to clarify the effects of TGF-beta1 and EGF on biomechanical properties using an in situ freeze-thaw ACL model in the rabbit. A total of 142 rabbits underwent the freeze-thaw treatment in the right ACL and were then divided into four groups. Group I served as a freeze-thaw, but otherwise untreated control. In Group II. a delivery vehicle (fibrin sealant) alone was applied. In Group III, 4-ng TGF-beta1 and 100-ng EGF mixed with the vehicle were applied. In Group IV, higher doses (2-microg TGF-beta1 and 50-microg EGF) of growth factors were mixed with the vehicle. The groups were compared at 6 and 12 weeks on the basis of mechanical properties, water content, and histological and ultrastructural observations. The cross-sectional area of Group III (average, 7.1 mm2) was significantly less than that of Groups I, II, and IV (9.0. 8.2. and 9.4 mm2. respectively) at 12 weeks. The tensile strength of Group lII (62.2 MPa) was significantly greater than that of Groups I, II, and IV (35.6, 43.7, and 36.9 MPa, respectively) at 12 weeks, while the water content of Group III (70.7%) was significantly lower than that of Group I (75.2%). No other significant differences occurred among Groups I, II, and IV. A unimodal distribution of collagen fibril diameters was noted in Groups I and II, while a bimodal pattern was found in Group III. This study demonstrated that low-dose application of TGFbeta1 and EGF significantly inhibited not only the increased water content and cross-sectional area, but also the decreased tensile strength caused by the freeze-thaw treatment, while a high dose of TGF-beta1 and EGF does not have the same beneficial effects.     

Improved flap viability with site-specific delivery of sildenafil citrate using fibrin glue

Sildenafil is a cyclic guanosine-specific phosphodiesterase type 5 (PD-5) inhibitor that is widely used for erectile dysfunction. Potent and competitive inhibition of PD-5 enhances levels of cyclic guanosine monophosphate (cGMP). Fibrin glue-apart from tissue fixation-has been used for slow release of drugs. In this study, local delivery of Sildenafil citrate with fibrin glue was accomplished to improve random flap survival. Fifty Wistar rats were randomized into 5 groups, and a standardized dorsal random-pattern skin flap was elevated in each rat. In Group I (n = 10), the base of the flap was divided, making it a "graft" control to study the graft effect. In Group II (n = 10), a thin Silastic sheet was used to separate the flap from the underlying vascular bed, and no pharmacologic treatment was given. In Group III (n = 10), only 0.5 mL of fibrin glue was applied to the flap donor site. In Group IV (n = 10), 2.5 mg of sildenafil citrate mixed in 0.5 mL of fibrin glue was applied to donor site of the flap, whereas 10 mg of sildenafil citrate mixed in 0.5 mL of fibrin glue was applied in Group V (n = 10). Area of flap survival was evaluated on postoperative seventh day. Total necrosis of all of the flaps was observed in "graft" control group (Group I). Sildenafil and fibrin glue groups (Group IV and V) resulted in a statistically significant decrease in flap necrosis compared with Groups II and III (P < 0.0001). A statistically significant difference could not be documented between Group II and Group III (P > 0.0001). The decrease in skin necrosis was statistically significant in Group V compared with Group IV (P < 0.0001). Histologic examination revealed significantly increased vascular density in Groups IV and V compared with Groups II and III (P < 0.0001), whereas a significant difference could not be documented between Groups IV and V (P > 0.0001) and between Groups II and III (P > 0.0001).In view of these results, topical sildenafil application seems to improve flap survival in random-pattern skin flaps in dose-dependent manner.     

Effect of controlled hemorrhage on tissue and serum cefazolin clearance

Effects of blood loss on tissue and serum antibiotic levels were investigated in 30 New Zealand white rabbits. Studies were conducted over a 3.5-hr period after intravenous administration of cefazolin, 30 mg/kg, in control animals (Groups I and IV, n = 5 each) and animals having 50% (Groups II and V, n = 5 each) or 100% (Groups III and VI, n = 5 each) of their blood volume removed and replaced with either Ringer's solution (Groups I, II, and III) or rabbit whole blood (Groups IV, V, and VI) sufficient to maintain central venous pressures at baseline levels. Periodic samples of retroperitoneal fat, iliac artery, and serum were assayed for cefazolin concentration by disc diffusion. Decreased tissue antibiotic levels were observed in animals undergoing 100% blood replacement (Groups III and VI) compared to controls (Groups I and IV) in both fat (P less than or equal to 0.01) and artery (P less than or equal to 0.01) at 90 min. Decreased antibiotic serum half-life accompanying hemorrhage existed when comparing Group II to I (P less than or equal to 0.05), Group III to I (P less than or equal to 0.01), and Group IV to V (P less than or equal to 0.01). The increased antibiotic clearance related to blood loss in this study justifies reassessment of intraoperative dosing intervals. More frequent dosing may be required to maintain stable tissue and serum antibiotic levels during substantial operative hemorrhage.     

Clonidine premedication effects on inhaled induction with sevoflurane in adults: a prospective, double-blind, randomized study

BACKGROUND: The purpose of this study was to evaluate whether oral clonidine premedication becomes an alternative to N2O in terms of shortening the induction time and attenuation of the adrenergic response to tracheal intubation during inhalation induction with sevoflurane, and to evaluate the quality of anesthetic induction according to the patient's satisfaction. METHODS: We studied 84 female patients who were randomly allocated into four study groups: Groups I and II received a placebo orally, and Groups III and IV received clonidine at 150 and 300 microg, respectively, 90 min before induction of anaesthesia. Patients were anesthetized using a triple-deep-breath technique with 5% sevoflurane in Groups I, III and IV, and with 60% N2O-5% sevoflurane in group II. RESULTS: Induction time was significantly longer (P < 0.05) in Group I. Increases in mean blood pressure and heart rate after tracheal intubation were significantly suppressed in Groups III and IV but not in Group II compared with Group I. Comfort and impression of anesthesia was better in Groups III and IV than in Groups I and II. CONCLUSION: In volatile anesthetic induction, pre-anesthetic clonidine may become an alternative to N2O and may provide more comfort than with N2O.     

Craniocervical junction fusions in patients with hindbrain herniation and syringohydromyelia

OBJECT: Patients with hindbrain herniation or the so-called Chiari malformation Type I (CM-I) and/or syringohydromyelia are treated with dorsal decompression alone; however, a small percentage of patients with other associated abnormalities require concomitant dorsal craniocervical junction (CCJ) fusion. The authors surveyed the indications for CCJ fusions in this population. METHODS: A retrospective review of University of Iowa medical records and radiographs obtained between 1996 and 2005 was performed. Inclusion criteria encompassed patients with diagnoses of CM-I and/or syringohydromyelia requiring dorsal CCJ fusions, and others with CCJ abnormalities who had CM-I and/or syringohydromyelia. RESULTS: Two hundred thirty-four patients were identified, all of whom were symptomatic at presentation. Their ages ranged from 2.5 to 86 years; 33% of the patients were < 16 years of age. Patients were categorized as follows, with some being assigned to > 1 category: Group I, congenital or acquired CCJ abnormalities with reducible bone compression (25% of patients); Group II, previous anterior CCJ/upper brainstem decompression (44%); Group III, occipitocervical complex instability with CM-I and/or syringohydromyelia but without CCJ bone abnormalities requiring adjunctive posterior fossa decompression (26%); and Group IV, musculoligamentous instability, either from pathological states or from muscle dehiscence from repeated posterior fossa procedures (14%). Instrumentation was used in 96% of patients, with all 96% receiving semirigid fixation with titanium loop and sublaminar cables; all fusion constructs incorporated autologous bone. At last follow-up evaluation, fusion was radiographically complete in 97%, and symptom improvement was seen in 92%. CONCLUSIONS: Dorsal CCJ fusions are required in patients with CM-I and/or syringohydromyelia who have concomitant CCJ abnormalities (Groups I and II). A definite group (CM-I and/or syringohydromyelia) without bone abnormality exists (Groups III and IV). This may be due to muscle weakness secondary to a high syrinx.     

Stage I and II posterior tibial tendon dysfunction treated by a structured nonoperative management protocol: an orthosis and exercise program

BACKGROUND: Posterior tibial tendon dysfunction (PTTD) is a relatively common problem of middle-aged adults that usually is treated operatively. The purpose of this study was to identify strength deficits with early stage PTTD and to assess the efficacy of a focused nonoperative treatment protocol. METHODS: Forty-seven consecutive patients with stage I or II posterior tibial tendon dysfunction were treated by a structured nonoperative protocol. Criteria for inclusion were the presence of a palpable and painful posterior tibial tendon, with or without swelling and 2) movement of the tendon with passive and active nonweightbearing clinical examination. The rehabilitation protocol included the use of a short, articulated ankle foot orthosis or foot orthosis, high-repetition exercises, aggressive plantarflexion activities, and an aggressive high-repetition home exercise program that included gastrocsoleus tendon stretching. Isokinetic evaluations were done before and after therapy to compare inversion, eversion, plantarflexion, and dorsiflexion strength in the involved and uninvolved extremities. Criteria for successful rehabilitation were no more than 10% strength deficit, ability to perform 50 single-support heel rises with minimal or no pain, ability to ambulate 100 feet on the toes with minimal or no pain, and ability to tolerate 200 repetitions of the home exercises for each muscle group. RESULTS: Before therapy weakness for concentric and eccentric contractures of all muscle groups of the involved ankle was significant (p<0.001). After a median of 10 physical therapy visits over a median period of 4 months, 39 (83%) of the 47 patients had successful subjective and functional outcomes, and 42 patients (89%) were satisfied. Five patients (11%) required surgery after failure of nonoperative treatment. CONCLUSION: This study suggests that many patients with stage I and II posterior tibial tendon dysfunction can be effectively treated nonoperatively with an orthosis and structured exercises.     

Microsurgical anatomy of the tentorial sinuses

Variations of the tentorial sinus of cadaver cerebellar tentoria were examined under a surgical microscope. The tentorial sinuses were classified into four groups: Group I, in which the sinus received venous blood from the cerebral hemisphere; Group II, in which the sinus drains the cerebellum; Groups III, in which the sinus originates in the tentorium itself; and Group IV, in which the sinus originates from a vein bridging to the tentorial free edge. The tentorial sinuses of Groups I and II were frequently located in the posterior portion of the tentorium. The sinuses of Group I were short and most frequently present in the lateral portion of the tentorium. The tentorial sinuses of Group II, which were usually large and drained into the dural sinuses near the torcular, were separated into five subtypes according to the draining veins and direction of termination. The tentorial sinuses of Groups III and IV were located near the tentorial free edge or the straight sinus. The draining patterns of the tentorial sinuses and their draining veins (so-called "bridging veins") were present in most cases. Knowledge of this anatomy can benefit the neurosurgeon carrying out repair near or on the cerebellar tentorium.