The efficacy of osteoporotic treatment in patients with new spinal vertebral compression fracture pain, ADL, QOL, bone metabolism and fracture-healing - In comparison with weekly teriparatide with bisphosphonate.

We conducted a randomized control study to compare the effects of pain, QOL, bone metabolism and fracture healing by administering bisphosphonate (BP) or weekly teriparatide preparation (W-TPTD) to 43 patients (5 males and 38 females) with fresh spinal vertebral compression fractures for osteoporosis. The patients were aged between 61 and 93 years old (mean 78.1 years). In principle, a MRI was used for any diagnosis of new vertebral fractures. From this study, lumbar spine bone mineral density (BMD), after 24 weeks of administration, showed a significant increase (p < 0.05) in both the BP group (mean 5.3%) and in the W-TPTD group (mean 4.9%). The W-TPTD group showed a better Roland-Morris disability Questionnaire (RDQ) improvement throughout the whole period of the study compared with the BP group, the difference was statistically significant after 24 weeks of administration (p < 0.05). The EuroQol 5 dimensions (EQ-5D) and visual analogue scale (VAS) score significantly improved over time in both groups (p < 0.05). The fracture-healing rate was observed in 45% of the BP group and 73% of the W-TPTD group at Week 12, and a statistically significant higher fracture-healing rate was obtained in the W-TPTD group compared to the BP group (p < 0.05). The mean time of fracture-healing was 3.9 months for the BP group and 2.8 months in the W-TPTD group. Statistically significant faster fracture-healing was observed in the W-TPTD group (p < 0.05). At Week 12 and Week 24, P1NP was significantly higher in the W-TPTD group compared to that of the BP group (p < 0.05). TRACP-5b showed no major fluctuations during the study period in either group. These results suggest that W-TPTD may promote better fracture healing of any new osteoporotic vertebral compression fractures compared with a BP.

Measuring the actual timing of liquid-reward delivery using a thermistor.

BACKGROUND: Determining the exact timing of reward delivery is critical in neurophysiological experiments. Despite the importance of this parameter, techniques for precisely measuring the exact delivery time of a liquid reward have been underdeveloped. Although there is always some latency between the computer command and reward delivery, the former has been used routinely to mark reward onset time. NEW METHOD: To address this issue, we developed two methods of estimating the time of liquid reward delivery. First, electrical conduction between two contacts at the outlet of a pipe was detected. This technique was impractical during normal experiments but was a direct and reliable method of measuring the precise timing of water outflow. Second, a self-heating thermistor inside the fluid delivery pipe was used. The thermistor detected a decrease in temperature upon commencement of water flow. RESULTS: The electrical contact began 50-80ms after the computer command. The thermistor-based delivery timing estimation was ∼40ms later than that measured by the electrical contact. The time lag was constant with minimal variance between trials within the same experimental setup. COMPARISON WITH EXISTING METHOD: As far as the time difference between the two methods is measured, the timing of water outflow can be estimated using the thermistor-based device. This is the first method of estimating the onset time of water flow during experiments. CONCLUSIONS: Our new system could be used to quantify setup-dependent changes in the timing of reward delivery, improving the sophistication of reward assessments in neurophysiological experiments.

Neural networks involved in artistic creativity.

Creativity has been proposed to be either the result of solely right hemisphere processes or of interhemispheric interactions. Little information is available, however, concerning the neuronal foundations of creativity. In this study, we introduced a new artistic task, designing a new tool (a pen), which let us quantitatively evaluate creativity by three indices of originality. These scores were analyzed in combination with brain activities measured by functional magnetic resonance imaging (fMRI). The results were compared between subjects who had been formally trained in design (experts) and novice subjects. In the experts, creativity was quantitatively correlated with the degree of dominance of the right prefrontal cortex over that of the left, but not with that of the right or left prefrontal cortex alone. In contrast, in novice subjects, only a negative correlation with creativity was observed in the bilateral inferior parietal cortex. We introduced structure equation modeling to analyze the interactions among these four brain areas and originality indices. The results predicted that training exerts a direct effect on the left parietal cortex. Additionally, as a result of the indirect effects, the activity of the right prefrontal cortex was facilitated, and the left prefrontal and right parietal cortices were suppressed. Our results supported the hypothesis that training increases creativity via reorganized intercortical interactions.

Effects of motor training on the recovery of manual dexterity after primary motor cortex lesion in macaque monkeys.

To investigate the effects of postlesion training on motor recovery, we compared the motor recovery of macaque monkeys that had received intensive motor training with those that received no training after a lesion of the primary motor cortex (M1). An ibotenic acid lesion in the M1 digit area resulted in impairment of hand function, with complete loss of digit movement. In the monkeys that had undergone intensive daily training (1 h/day, 5 days/wk) after the lesion, behavioral indexes used to evaluate manual dexterity recovered to the same level as in the prelesion period after 1 or 2 mo of postlesion training period. Relatively independent digit movements, including precision grip (prehension of a small object with finger-to-thumb opposition), were restored in the trained monkeys. Although the behavioral indexes of manual dexterity recovered to some extent in the monkeys without the postlesion training, they remained lower than those in the prelesion period until several months after M1 lesion. The untrained monkeys frequently used alternate grip strategies to grasp a small object with the affected hand, holding food pellets between the tip of the index finger and the dorsum of the thumb. These results suggest that the recovery after M1 lesion includes both use-dependent and use-independent processes and that the recovery of precision grip can be promoted by intensive use of the affected hand in postlesion training.

MST neurons code for visual motion in space independent of pursuit eye movements.

When a person tracks a small moving object, the visual images in the background of the visual scene move across his/her retina. It, however, is possible to estimate the actual motion of the images despite the eye-movement-induced motion. To understand the neural mechanism that reconstructs a stable visual world independent of eye movements, we explored areas MT (middle temporal) and MST (medial superior temporal) in the monkey cortex, both of which are known to be essential for visual motion analysis. We recorded the responses of neurons to a moving textured image that appeared briefly on the screen while the monkeys were performing smooth pursuit or stationary fixation tasks. Although neurons in both areas exhibited significant responses to the motion of the textured image with directional selectivity, the responses of MST neurons were mostly correlated with the motion of the image on the screen independent of pursuit eye movement, whereas the responses of MT neurons were mostly correlated with the motion of the image on the retina. Thus these MST neurons were more likely than MT neurons to distinguish between external and self-induced motion. The results are consistent with the idea that MST neurons code for visual motion in the external world while compensating for the counter-rotation of retinal images due to pursuit eye movements.

A prospective randomized study of posterolateral lumbar fusion using osteogenic protein-1 (OP-1) versus local autograft with ceramic bone substitute: emphasis of surgical exploration and histologic assessment.

STUDY DESIGN: A prospective, randomized and controlled study. OBJECTIVES: To evaluate the osteoinductive property of Osteogenic Protein-1 (OP-1 or BMP-7) and fusion rate in human instrumented posterolateral lumbar fusion through radiographic examination, surgical exploration, and histologic assessment. SUMMARY OF BACKGROUND DATA: The use of osteoinductive agents is a current topic in spinal fusion. Numerous preclinical investigations have demonstrated efficacy of osteoinductive proteins in spinal fusion, but few human clinical studies have been reported. METHODS: Nineteen patients with L3-L4 or L4-L5 degenerative spondylolisthesis underwent posterolateral lumbar fusion using pedicle screw instrumentation. The patients were randomized to receive either OP-1 Putty (3.5 mg OP-1/g of collagen matrix per side) alone (n = 9), or local autograft with HA-TCP granules (n = 10). Fusion status was evaluated using plain radiography and CT scan. Radiographic fusion criteria included less than 5 degrees of angular motion, less than 2 mm of translation, and evidence of bridging bone in the posterolateral lumbar area in which the graft materials were placed following decortication. After a minimum 1-year follow-up, the patients who showed radiographic evidence of fusion underwent instrumentation removal and surgical exploration of the fusion site. Biopsy specimens were taken from the fusion mass and evaluated histologically. RESULTS: Radiographic fusion rate was 7 of 9 OP-1 patients and 9 of 10 control patients. Based on surgical exploration of these 16 patients, new bone formation was macroscopically observed in the posterolateral lumbar region in all cases; however, solid fusion was observed in 4 of 7OP-1 and 7 of 9 HA-TCP/autograft patients. Histologic assessment demonstrated viable bone in 6 of 7 OP-1 patients. All the control (HA-TCP/autograft) specimens contained viable bone and fibrous tissue surrounding ceramic granules, suggesting slow incorporation of the graft material. CONCLUSIONS: In a human posterolateral lumbar spine trial, OP-1 reliably induced viable amounts of new bone formation, but the fusion success rate evaluated by surgical exploration was only 4 of 7.

Cortical activity in multiple motor areas during sequential finger movements: an application of independent component analysis.

Multiple cortical regions such as the supplementary motor area (SMA), premotor cortex (PM), and primary motor cortex (M1) are involved in the sequential execution of hand movements, but it is unclear how these areas collaborate in the preparation and execution of ipsilateral and contralateral hand movements. In this study, we used right-handed subjects to examine the spatial distribution and temporal profiles of motor-related activity during visually cued sequential finger movements by applying independent component analysis (ICA) to event-related functional magnetic resonance imaging (fMRI) signals. The particular merit of the ICA method is that it allows brain activity in individual subjects to be elucidated without making a priori assumptions about the anatomical areas that are activated or the temporal profile of activity. By applying ICA, we found that (1) the SMA contributed to both the preparation and execution of movements of the right and left hand; (2) the left M1 and dorsal premotor cortex (PMd) contributed to both the preparation and execution of movements of the right and left hand, whereas the right M1 and PMd contributed mainly to the execution of movements of the left hand; (3) pre-SMA areas were activated in some subjects in concert with the posterior parietal and prefrontal cortex; and (4) fMRI signals over superficial cortical draining veins could be distinguished from cortical activation. We suggest that ICA is useful for categorizing distributed task-related activities in individual subjects into several spatially independent activities that represent functional units in motor control.

New treatment of lumbar disc herniation involving 5-hydroxytryptamine2A receptor inhibitor: a randomized controlled trial.

OBJECT: Serotonin or 5-hydroxytryptamine (5-HT) is a chemical mediator associated with nucleus pulposus-induced radiculopathy. Inhibition of 5-HT receptors may potentially alleviate symptoms in patients with lumbar disc herniation. This prospective randomized controlled study was performed to evaluate the efficacy of the 5-HT2A receptor inhibitor in the treatment of symptomatic lumbar disc herniation. METHODS: Forty patients with sciatica due to L4-5 or L5-S1 disc herniation were randomly allocated to treatment with the 5-HT2A inhibitor (sarpogrelate 300 mg/day) or nonsteroidal antiinflammatory drugs (NSAIDs; diclofenac 75 mg/day). Low-back pain, leg pain, and numbness were evaluated using a visual analog scale (VAS) before and after a 2-week course of treatment. The patients received only allocated medicine during the 2-week regimen and were thereafter allowed to choose any treatment options depending on their residual symptoms. One-year clinical outcomes were assessed based on the rates of additional medical interventions. The mean VAS score improvements in the 5-HT2A and NSAID groups were 33 and 46% for low-back pain, 32 and 32% for leg pain, and 35 and 22% for leg numbness, respectively. After the 2-week regimen, no additional medical interventions were required in 50% of 5-HT2A-treated patients and 15% of those receiving NSAIDs. Epidural or nerve root block procedures were performed in 35% of the 5-HT2A group and 45% of the NSAID group. Surgery was required in 20% of the 5-HT2A group and 30% of the NSAID group patients. CONCLUSIONS: The current study provided evidence that the efficacy of the 5-HT2A inhibitor was comparable with that of NSAID therapy for lumbar disc herniation. The 5-HT2A inhibitor has the potential to alleviate symptoms in patients with lumbar disc herniation.

Neuronal mechanisms encoding global-to-fine information in inferior-temporal cortex.

Sugase et al. found that global information is represented at the initial transient firing of a single face-responsive neuron in inferior-temporal (IT) cortex, and that finer information is represented at the subsequent sustained firing. A feed-forward model and an attractor network are conceivable models to reproduce this dynamics. The attractor network, specifically an associative memory model, is employed to elucidate the neuronal mechanisms producing the dynamics. The results obtained by computer simulations show that a state of neuronal population initially approaches to a mean state of similar memory patterns, and that it finally converges to a memory pattern. This dynamics qualitatively coincides with that of face-responsive neurons. The dynamics of a single neuron in the model also coincides with that of a single face-responsive neuron. Furthermore, we propose two physiological experiments and predict the results from our model. Both predicted results are not explainable by the feed-forward model. Therefore, if the results obtained by actual physiological experiments coincide with our predicted results, the attractor network might be the neuronal mechanisms producing the dynamics of face-responsive neurons.

Non-fusion surgery for degenerative spondylolisthesis using artificial ligament stabilization: surgical indication and clinical results.

STUDY DESIGN: A retrospective study. OBJECTIVES: To report midterm clinical and radiographic results of Graf artificial ligament stabilization in the treatment of degenerative spondylolisthesis and to evaluate the role of this procedure and its surgical indications for surgical success. SUMMARY OF BACKGROUND DATA: Nonfusion surgeries including artificial disc replacement and ligamentoplasty are increasingly gaining interest to avoid adverse effects of spinal fusion. METHODS: Sixty-four consecutive patients with degenerative spondylolisthesis underwent artificial ligament stabilization. Surgical indication was symptomatic degenerative spondylolisthesis with <25% of vertebral slip, coronal facet tropism, and minimal disc space narrowing. Radiographic and clinical assessments were performed before surgery, immediately after surgery, and at the final follow-up. Mean follow-up period was 67 months (36-112 months). RESULTS: Visual analog scales of low back pain and sciatic symptoms were significantly improved. Radiographic assessments demonstrated that segmental lordosis was maintained in 12.2 degrees , and flexion-extension motion was averaged 4.7 degrees at the final follow-up. Facet arthrodesis spontaneously occurred in 12 cases (18.8%) at an average of 59.5 months after surgery. Although vertebral slip was not improved, postoperative disc space narrowing was minimal. Additional surgeries were required in 4 cases for adjacent segment pathologies (6.3%). One patient (1.6%) underwent consequent spinal arthrodesis at the ligamentoplasty level. CONCLUSIONS: Artificial ligament stabilization did not improve the vertebral slip but maintained lordosis and preserved segmental motion in 80% of patients. This procedure is an effective alternative to spinal arthrodesis in the treatment of symptomatic degenerative spondylolisthesis (Grade I) with minimal disc space narrowing and coronal facet tropism.

Population dynamics of face-responsive neurons in the inferior temporal cortex.

Neurons in the inferior temporal (IT) cortex of monkeys respond selectively to complex visual stimuli, such as faces. Single neurons in the IT cortex encode different kinds of information about visual stimuli in their temporal firing patterns. To understand the temporal aspects of the information encoded at a population level in the IT cortex, we applied principal component analysis (PCA) to the responses of a population of neurons. The responses of each neuron were recorded while visual stimuli that consisted of geometric shapes and faces of humans and monkeys were presented. We found that global categorization, i.e. human faces versus monkey faces versus shapes, occurred in the earlier part of the population response, and that fine categorization occurred within each member of the global category in the later part of the population response. A cluster analysis, a mixture of Gaussians analysis, confirmed that the clusters in the earlier part of the responses represented the global category. Moreover, the clusters in the earlier part separated into sub-clusters corresponding to either human identity or monkey expression in the later part of the responses, and the global categorization was maintained even after the appearance of the sub-clusters. The results suggest that a hierarchical relationship of the test stimuli is represented temporally by the population response of IT neurons.

Accelerated recognition of left oblique views of faces.

Because faces in portraits are depicted more frequently in a left rather than a right oblique (half-profile or 3/4) view, we addressed the question of whether people find it easier to recognize the left or right 3/4 view of a familiar person's face. We examined the ability of 13 subjects to match familiar faces that were presented in either the left or right 3/4 view, with names that were presented either before or after the faces (face-name and name-face matching tasks, respectively). In both tasks, the subjects responded more rapidly to a left than to a right 3/4 view of the same face. This suggests that during face recognition the processing of information from faces that are presented in the left 3/4 view is dominant over the processing of right 3/4 views of familiar faces.

Dominance of the left oblique view in activating the cortical network for face recognition.

Faces in portraits are often depicted from the left 3/4 view (an oblique view of the face that is intermediate between the frontal view and left profile). Here, we used functional magnetic resonance imaging (fMRI) to show that, compared with photographs of right 3/4 views of familiar faces, photographs of left 3/4 views of the same faces elicited stronger neural responses in the right middle occipital/inferior parietal cortex, and right inferior frontal gyrus; which are known to be involved in face recognition. By contrast, there was no differential activation in the temporal cortex including the superior temporal sulcus and fusiform gyrus, which are thought to process face-related visual stimuli at a stage that precedes recognition. We suggest that the preference for the left 3/4 view of faces was produced at a later stage of facial information processing that involves attention or memory retrieval.

Pitfalls of anterior cervical fusion using titanium mesh and local autograft.

Cervical fusion cages have been developed to provide an anterior structural support without harvesting tricortical iliac bone. Limited numbers of investigations have focused on pitfalls of anterior cervical fusion using cage implants. The objective of this study is to report clinical results and implant-related complications in anterior cervical fusion using titanium mesh and anterior plating. Twenty-four cases with anterior cervical fusion using a titanium mesh with local autograft and anterior plating were reviewed. One-level fusion was performed in 7 cases, and 17 patients underwent two-level fusion with corpectomy. The mean follow-up period was 27 months. Radiographic assessment included sagittal alignment, fusion status, and complications related to cage implants. Iliac bone graft harvesting was obviated in all the patients, whereas 15 patients required concomitant use of ceramic bone substitute. Sagittal alignment of the operative level was lordotic in 19 cases (79%) and neutral in 5 cases (21%) at the final follow-up. No late kyphotic collapse was observed. Twenty-three cases (96%) achieved a solid fusion, whereas the time to fusion was averaged 6.2 months. Cage subsidence frequently occurred in 42% of upper vertebrae and 50% of lower vertebrae. The use of titanium mesh and local autograft for anterior cervical fusion obviated the need for harvesting iliac bone block and provided structural anterior column support. However, it required a longer period to achieve a solid fusion when compared with tricortical iliac autograft. Cage subsidence was frequently observed in the early postoperative period.

Intraoperative biomechanical assessment of lumbar spinal instability: validation of radiographic parameters indicating anterior column support in lumbar spinal fusion.

STUDY DESIGN: Lumbar spinal instability was evaluated using radiographic parameters and intraoperative biomechanical measurement. OBJECTIVES: To validate a conventional radiographic assessment using an intraoperative biomechanical measurement and to determine the radiographic parameters indicating anterior column support in lumbar spinal fusion. BACKGROUND: Posterior lumbar interbody fusion is gaining acceptance in the treatment of degenerative spondylolisthesis, whereas posterolateral fusion alone may result in good clinical outcomes. A quantitative biomechanical assessment of spinal instability is essential to determine the optimal method of spinal arthrodesis. MATERIALS AND METHODS: Nineteen cases with symptomatic degenerative spondylolisthesis were included in this study. All were candidates for pedicle-screw instrumented lumbar arthrodesis. A total of five L3-L4 segments and seventeen L4-L5 segments were investigated. Radiographic assessment included disc angle, range of motion (ROM), percent of slip, and percent of posterior disc height. Distraction stiffness of the operative segment was measured intraoperatively using a strain-gauged spreader. RESULTS: Disc angle in flexion and ROM were highly correlated to distraction stiffness. Severity of slip, disc space narrowing, and facet tropism did not influence the distraction stiffness. The cases with segmental kyphosis in flexion had significantly lower distraction stiffness than those showing segmental lordosis in flexion. CONCLUSIONS: Disc angle in flexion and ROM were the most prognostic parameters of lumbar distraction instability. Although the option of spinal arthrodesis method should be determined based on both clinical manifestation and imaging studies, the current study demonstrated that providing of anterior column support is biomechanically reasonable for degenerative spondylolisthesis with segmental kyphosis in flexion.

Description of a new endoscopic posterior cruciate ligament reconstruction and comparison with a 2-incision technique.

PURPOSE: We introduce our technique (a new route for the graft) of endoscopic posterior cruciate ligament (PCL) reconstruction and describe the advantages in comparison with the conventional surgical technique. TYPE OF STUDY: Nonrandomized control study. METHODS: The idea of this surgical technique is to minimize graft angulation at the inner edge of the bone tunnel. The tibial entry point of the guide pin is under the tibial lateral subcondylar flare, approximately 1 to 2 cm anterior to the posterior cortex. This creates less graft angulation on the posterior aspect of the tibia. A new drill system has been devised to allow antegrade femoral drilling starting from inside the notch. This method also allows better femoral tunnel orientation. As a substitute graft material, we use autogenous hamstring tendons, and we secure them with an EndoButton (Smith & Nephew, Andover, MA) and post screw. From 1992 to 1995, 43 2-incision PCL reconstructions using autogenous hamstring tendons were performed. From 1995 to 2001, 90 endoscopic PCL reconstructions using looped autogenous hamstring tendons and an EndoButton were performed. Cases were specified according to the inclusion criteria of this study. As a result, 51 patients were included in this study. The 2-incision group comprised 22 patients, and the endoscopic group comprised 29 patients. The clinical evaluation was performed using the International Knee Documentation Committee (IKDC) form. The quadriceps strength was measured using Biodex System II (Biodex, New York, NY). The period of time to achieve 90 degrees flexion after surgery was also compared. RESULTS: No significant differences were seen between the 2 groups tested with respect to the overall IKDC rating score. Side-to-side differences of anteroposterior total laxity (KT-1000, manual maximum) was 3.95 +/- 1.96 mm in the 2-incision group and 2.38 +/- 1.42 mm in the endoscopic group (P <.05). The average time to achieving 90 degrees of flexion after surgery was 16.6 +/- 8.6 days in the 2-incision group and 12.1 +/- 3.5 days in the endoscopic group. Achievement of range of motion in the endoscopic group was significantly shorter. The peak torque of isokinetic contraction in the endoscopic group was significantly greater than in the 2-incision group 1 year after surgery. CONCLUSIONS: Better posterior stability and quicker postoperative recovery of range of motion and muscle strength were advantages of the endoscopic technique over the 2-incision technique in PCL reconstruction.

Efficacy of serotonin receptor blocker for symptomatic lumbar disc herniation.

Serotonin is one of the chemical mediators associated with nerve root inflammation and sciatic symptoms in lumbar disc herniation. The efficacy of serotonin 5-HT(2A) receptor blocker was examined in 44 patients with symptomatic lumbar disc herniation. A selective 5-HT(2A) receptor blocker (sarpogrelate hydroxychloride) was administered orally at a dose of 300 mg per day for 2 weeks. Visual analog scales of low back pain, sciatic pain, and numbness were significantly improved after the administration of the serotonin 5-HT(2A) receptor blocker. Clinical results were good (> 50% pain relief) in 23 patients, fair (25%-50% pain relief) in five patients, and poor (< 25% of pain relief) in 16 patients. Nineteen patients eventually required surgery because of muscle weakness or cauda equina symptoms. The effect of 5-HT(2A) blocker was good in 64% of patients who had uncontained disc herniation, whereas all patients with contained disc herniation had fair or poor results. Patients with uncontained disc herniation responded more favorably to the 5-HT(2A) blocker treatment than patients with contained disc herniation. A 5-HT(2A) blocker has the potential to block the cascade of acute nerve root inflammation and to alleviate symptoms in lumbar disc herniation.

Two-stage reconstruction with autografts for knee dislocations.

Traumatic knee dislocations are severe injuries that involve damage to the anterior cruciate ligament, the posterior cruciate ligament, and the lateral or medial ligamentous structures. There are no established methods of treatment. The objective of the current study was to report the clinical outcome of a two-stage autologous reconstruction on nine knees (eight patients). The mean followup was 40.1 months. The first stage of the reconstruction was done at a mean of 2 weeks after the injury, and the posterior cruciate ligament was reconstructed by an arthroscopically assisted technique using contralateral autogenous hamstring tendon as the graft material. Three months later, the second stage of the reconstruction was done for the ligaments that had not healed with conservative treatment. Arthroscopically assisted anterior cruciate ligament reconstruction was done on all of the knees using the ipsilateral autogenous hamstring tendon or bone-patellar tendon-bone as the graft material. At the same time, a medial collateral ligament reconstruction using an autogenous semitendinosus tendon was done on one knee, and reconstruction of the posterolateral ligamentous structures using a biceps tendon was done on three knees. Each of the knees that was reconstructed was capable of full extension, and the mean degree of passive flexion was 139.5 degrees +/- 5.2 degrees. The mean side-to-side difference in anteroposterior total laxity (KT-1000 arthrometer, manual maximum) was 2.3 +/- 1.9 mm. None of the knees had lateral or medial instability. All of the injured ligaments were able to be reconstructed with autografts, and severe contracture was able to be prevented. A good clinical outcome can be achieved when two-stage reconstruction is used for traumatic knee dislocations.

Clinical results of single-level posterior lumbar interbody fusion using the Brantigan I/F carbon cage filled with a mixture of local morselized bone and bioactive ceramic granules.

STUDY DESIGN: A retrospective study to evaluate the results of single-level posterior lumbar interbody fusion (PLIF) using the Brantigan I/F cage (DePuy AcroMed Corp., Raynham, MA) filled with a mixture of local morselized autologous bone and bioactive ceramic granules. OBJECTIVES: To report the clinical and radiologic results of PLIF using the Brantigan I/F cage for lumbar degenerative pathologies with instability. SUMMARY OF BACKGROUND DATA: The Brantigan I/F cage for PLIF was designed to improve the fusion success of interbody fusion by separating the mechanical and biologic functions of PLIF using an implant device and autologous bone from the iliac crest. Although high fusion rates have been reported, donor site morbidity caused by bone harvest from the iliac crest remains a concern. The possibility of accomplishing cage PLIF using a mixture of local morselized bone and a bone extender was studied. METHODS: A total of 25 patients underwent single-level PLIF using the Brantigan I/F cage filled with a mixture of local morselized bone and bioactive ceramic granules. All patients were observed for more than 2 years (average 2 years 7 months) and evaluated by clinical rating and radiograph. RESULTS: Preoperative Japanese Orthopedic Association clinical scores were significantly improved in all patients at the time of follow-up. The average improvement rate was 83.1%. There were no serious complications. Minor complications included two dural tears and two cases of thrombophlebitis. No patient required blood transfusion. All patients achieved radiographic fusion and radiographic stability, although two patients fused in a collapsed position. Regional alignment of the operated segments was restored at surgery and maintained at the time of final follow-up. There were statistical improvements in percent slip and percent posterior disc height in patients with spondylolisthesis. CONCLUSIONS: Posterior lumbar interbody fusion using the Brantigan I/F cage with a mixture of local morselized bone and bioactive ceramic granules can yield a solid union with satisfactory regional alignment and adequate disc height without harvest of iliac crest bone.

A new endoscopic posterior cruciate ligament reconstruction: Minimization of graft angulation.

PURPOSE: The purpose of this report is to present a new surgical technique for endoscopic posterior cruciate ligament (PCL) reconstruction and to elucidate the preliminary results. Surgical Technique: The concept of this surgical technique is to minimize the graft angulation at the inner edge of the bone tunnel. The tibial entry point of the guide pin is under the tibial lateral subcondylar flare approximately 1 to 2 cm anterior to the posterior cortex and 4 cm distal to the joint surface. This creates less graft angulation on the posterior aspect of the tibia. A new drill system has been devised to allow antegrade femoral drilling starting from inside the notch. This method also allows better femoral tunnel orientation. As a substitute graft material, we use autogenous hamstring tendons, and we secure them with an EndoButton (Smith & Nephew, Mansfield, MA) and post screw. METHODS: Since 1995, 40 knees have undergone endoscopic PCL reconstruction. Twenty-one patients were evaluated after a minimum follow-up of 1 year (17.9 +/- 7.7 mo). The clinical evaluation was performed using the International Knee Documentation Committee (IKDC) form. RESULTS: The range of motion was rated as A for 17 cases, B in 3 cases, and C in one case. The total anteroposterior translation (KT-1000, manual-maximum) showed a range of 1.0 to 5.5 mm (mean, 2.8 mm). The ratings of the ligament examination were A in 9 cases and B in 12 cases. The final IKDC evaluation was A (normal) in 3 cases, B (nearly normal) in 17 cases, and C (abnormal) in 1 case. CONCLUSIONS: A good clinical outcome was achieved with our endoscopic PCL reconstruction. The reduction of the graft angulation may contribute to the good results for PCL reconstruction.