Comparison of 2-octyl cyanoacrylate with polyester mesh with standard suture and staples in total knee and hip arthroplasty

OBJECTIVE

The use of 2-octyl cyanoacrylate with polyester mesh (OCA-M) has become common in total hip and knee arthroplasty (THA, TKA). We aimed to compare the safety and cosmetic outcomes between OCA-M and standard suture techniques and staples, and determine whether OCA-M can safely be used for TKA.

METHOD

Inclusion criteria were patients who underwent THA or TKA from January 2010 to October 2011 (Suture group), November 2011 to August 2013 (Staple group), March 2017 to September 2018 (OCA-M group). Exclusion criteria was loss of imaging data. Complications during hospitalisation (early complication) and after discharge (late complication) were compared in groups. Plastic and orthopaedic surgeons performed cosmetic evaluations with the modified Vancouver Scar Scale (VSS) and Likert scale at three and six months postoperatively and compared in groups.

RESULTS

A total of 249 arthroplasties (suture group=88 patients; staple group=94 patients; OCA-M group=67 patients) were included in the study. The OCA-M group had a significantly lower early complication rate than the suture group (p=0.015). For THA, the OCA-M group had a significantly lower total complication rate than the suture group (p=0.048). For TKA, there was no significant difference among the three groups. The complication rate in the OCA-M group showed no significant difference between THA/TKA. With regards to the VSS, the OCA-M group was significantly better for cosmetic qualities than the suture group (p=<0.001, p=0.021 at three and six months, respectively). For the Likert scale, the OCA-M group was also significantly better for cosmetic qualities than the suture group and staple group (suture-OCA-M, p=0.003 (three months), p=<0.001 (six months); staple-OCA-M, p=0.027 (three months)).

CONCLUSION

In this study, the OCA-M complication rate was low compared to suturing and similar to stapling. Moreover, better cosmetic outcomes were achieved compared to suturing and stapling.

Does posterior tibial slope laterality exist? A matched cohort study between ACL-injured and non-injured knees

PURPOSE

The purpose of this study is to examine 1) the degree and frequency of laterality in posterior tibial slope (PTS) with control and anterior cruciate ligament (ACL) injury groups and 2) the laterality of PTS between sides of injury and dominant legs in patients with primary ACL injuries.

METHODS

A total of 187 consecutive patients with clinically diagnosed noncontact ACL injuries and an age- and sex-matched 1:1 control group were identified. PTS was measured using three different methods (aPTS = anterior PTS, mPTS = middle PTS, pPTS = posterior PTS) on a lateral knee radiograph. PTS of the left and right sides were compared between the patients in the control and ACL-injured groups, and between the injured and non-injured and dominant and non-dominant legs among the patients in the ACL-injured group. The patients with a difference in PTS of ≥ 3° in mPTS were selected. The percentages were compared between left and right between and among both groups, and between the injured and non-injured, and non-dominant and dominant leg, for the ACL group. Multiple regression analysis was performed to analyze the factors influencing the degree of mPTS.

RESULTS

Both control (Right vs Left: aPTS; 9.0 ± 2.5 vs 10.5 ± 3.0, mPTS; 6.6 ± 2.3 vs 8.1 ± 2.7, pPTS; 4.0 ± 2.4 vs 5.6 ± 2.8, respectively, p < 0.01) and ACL injury groups (Right vs Left: aPTS; 10.6 ± 3.0 vs 12.6 ± 2.9, mPTS; 7.6 ± 2.6 vs 9.5 ± 2.6, pPTS; 5.9 ± 3.0 vs 8.0 ± 3.0, respectively, p < 0.01) had a significantly greater PTS on the left than on the right side, and the ACL group had a significantly greater PTS than the control group on both the left and right sides. In the ACL group, PTS was greater on the injured and the non-dominant leg than on the non-injured and the dominant leg. The percentage of patients with a PTS difference of ≥ 3° was significantly greater on the left, injured, and non-dominant leg (95.3% vs 4.7%, 73.8% vs 26.2%, 86.1% vs 13.9%, respectively, p < 0.01). Only the left leg had a significant influence on PTS in the multivariate analysis.

CONCLUSION

There was laterality in PTS within control and ACL injury groups, and this information is of benefit for effective treatment of ACL injuries.

LEVEL OF EVIDENCE

Level III.

Posterior Opening-Wedge Osteotomy for Posterior Tibial Slope Correction of Failed Anterior Cruciate Ligament Reconstruction

A large posterior tibial slope (PTS) has been widely recognized as a potential risk factor in loosening and retear after anterior cruciate ligament reconstruction. Anterior closed-wedge osteotomy is an effective surgical approach to mitigate this risk factor but presents several disadvantages. We describe in this Technical Note an original PTS correction technique called the posterior open-wedge osteotomy. The posterior surface of the proximal tibia is exposed, and 2 K-wires are inserted anteroposteriorly as osteotomy guides, and one wire is inserted mediolaterally as a hinge blocker. The osteotomy is performed from the posterior side and advanced to the anterior side using a single-bladed reciprocating saw. The slope is corrected by opening the osteotomy plane posteriorly with a spreader. The correction is maintained by inserting the harvested fibula fragments into the open space, and the fixation is completed with a locking plate to ensure firm fixation and allow early rehabilitation. This procedure can be an effective solution for patients with various risk factors for retear of the anterior cruciate ligament graft, including abnormal PTS.

Anatomical Double-Bundle Anterior Cruciate Ligament Reconstruction With Suture Augmentation

Ultra-high molecular weight polyethylene sutures are used for repair and reconstruction of extra-articular ligaments in the knee, elbow, and ankle joints. In recent years, the use of these sutures has become popular in a suture augmentation technique and has been applied for use in the reconstruction of the anterior cruciate ligament, which is an intra-articular ligament. Although several surgical techniques have been described in Technical Notes, all reports have been for single-bundle reconstruction, and none have applied the technique to double-bundle reconstruction. This Technical Note provides a detailed description of an anatomical double-bundle anterior cruciate ligament reconstruction combined with the suture augmentation technique.

Macroscopic and microscopic findings of multi-folded hamstring grafts of anatomical double-bundle ACL reconstruction 13 years after surgery

A 49-year-old woman underwent anatomic double-bundle anterior cruciate ligament reconstruction using a hamstring tendon. Due to knee osteoarthritis progression, total knee arthroplasty was performed 13 years after the surgery. The anteromedial (AM) bundle was composed partly of tendon-like tissue and partly of scar-like tissue. In the tendon-like part of the AM bundle, the collagen fibers were slightly loose and showed a low-frequency crimp structure with an ovoid cell shape. In contrast, the collagen arrangement in the scar-like part was irregular, edematous, and sparsely cell-dense, with an ovoid cell shape. The posterolateral bundles were generally composed of spindle-shaped cells, and the collagen was arranged in tight cohesion and had well-demarcated bundles with normal crimping. Within the tibial tunnel, the graft was mainly connected to the surrounding lamellar bone on the posterior sides, with sparser connections on the anterior and medial/lateral side. The findings of this long-term case provide valuable information to enable understanding of multiple-folded hamstring tendons.Level of evidence V.

Effect of a new remnant-preserving technique with anatomical double-bundle anterior cruciate ligament reconstruction on MRI-based graft maturity: a comparison cohort study

PURPOSE

To investigate the effects of a new remnant-preserving double-bundle anterior cruciate ligament reconstruction (ACLR) technique, focused on avoiding remnant damage and preserving continuity of remnants, on graft maturity using magnetic resonance imaging (MRI).

METHODS

A total of 169 patients were divided into three groups: 41 in the preservation group, 70 in the resection group, and 58 in the absent group. In the preservation group, rather than passing the graft through the remnant tissue, the graft was reconstructed such that the anteromedial and posterolateral bundles sandwiched the remnant to avoid damage to the remnant and maintain its continuity. Based on 1-year postoperative MRI, the grafts were divided into three regions: distal, middle, and proximal. The signal/noise quotient (SNQ) of each region of interest was calculated to evaluate the signal intensity of the graft and was compared among the three groups. Additionally, to identify factors influencing graft maturity, a multiple regression analysis was performed with SNQ as the dependent variable and patient demographics, bone morphology, and surgical factors as independent variables.

RESULTS

In a three-group comparison of mean SNQs, the distal region was 3.3 ± 3.4, 8.9 ± 8.3, and 9.0 ± 8.6 (p < 0.001), the middle region was 5.3 ± 3.7, 10.9 ± 11.1, and 11.3 ± 10.2 (p < 0.001), and the proximal region was 6.8 ± 4.5, 11.1 ± 8.8, and 11.7 ± 10.8 (p = 0.017), in order of the preservation, resection, and absent groups, respectively. That indicated that the remnant-preserving ACLR was more hypointense than ACLR with remnant resection or absent in all three regions. Multiple regression analysis showed that remnant preservation remained the relevant factor affecting SNQ of the graft at the distal and middle levels.

CONCLUSION

The new remnant-preserving anatomic double-bundle ACLR had significantly better graft maturity, measured by SNQ on MRI, than the remnant resection and absent groups. The remnant procedure was the relevant factor affecting graft maturity.

LEVEL OF EVIDENCE

Level III.

A new remnant preservation technique reduces bone tunnel enlargement after anatomic double-bundle anterior cruciate ligament reconstruction

PURPOSE

To investigate the effect of a new remnant preservation technique with a focus on remnant continuity on postoperative femoral and tibial tunnel enlargement after anatomical double-bundle anterior cruciate ligament reconstruction (ACLR).

METHODS

A total of 150 knees were divided into three groups: Preservation Group (Group P: 49 knees), wherein the remnant continuity remained after tunnel creation; Resection Group (Group R: 47 knees), wherein the remaining remnant was resected, and Absent Group (Group A: 54 knees), wherein the remnant had no femoral attachment before tunnel creation. In Group P, the remnant maintained continuity, and the anteromedial (AM) and posterolateral (PL) bundles were positioned anterior and posterior to the remnant, respectively. Computed tomographic scans were performed at 1 week and 1 year after surgery, and the cross-sectional area of each tunnel aperture was measured. Tunnel enlargement was compared among the three groups by one-way analysis of variance (ANOVA) and the Bonferroni test. Univariate and multivariate logistic analyses were performed to identify the risk factors for tunnel enlargement in demographic and radiographic data.

RESULT

For femoral AM tunnels, the tunnel enlargement of Group P was significantly smaller than Groups R and A (p < 0.001), femoral PL (p < 0.001 vs. R and A), tibial AM (p < 0.001 vs. R, 0.002 vs. A), and tibial PL (p < 0.001 vs. R, 0.002 vs. A). There was no significant difference between Groups R and A. Multivariate logistic analysis showed that remnant preservation was a significant factor in reducing tunnel enlargement in the femoral AM, femoral PL, tibial AM, and tibial PL.

CONCLUSION

The new remnant-preserving anatomical double-bundle ACLR, which preserves the continuity of the remnant, prevented all bone tunnel enlargement at 1 year postoperatively.

LEVEL OF EVIDENCE

Level III.

Anatomical implications of the subvastus approach on major vascular injury during a distal femoral osteotomy: a computed tomographic venography study

PURPOSE

This study evaluated major vascular injury risk in distal femoral osteotomy (DFO) via the subvastus approach and examined the relationship between the posterior border of the vastus medialis (VM) and the superficial femoral artery (SFA) and vein (SFV).

METHODS

Eighty limbs from 80 patients were evaluated using lower extremity computed tomographic venography. The positional relationship between the VM, SFA, and SFV was evaluated by measuring the angle between each structure and the horizontal reference point (VMA: VM angle, FAA (femoral arterial angle), FVA (femoral venous angle) and the distance between VM and the SFA and SFV (VMAD: VM-arterial distance, VMVD: VM-venous distance) in each axial slice (0/10/20/30/40 mm) proximal to the level of the superior patellar margin. The proximity of the posterior border of the VM and the SFA/SFV as a vertical distance, measured between the slice of the superior border of the patella and the slice where the posterior border of the VM contacted the SFA was evaluated. Single and multiple regression analyses were performed using the vertical distance as the objective variable.

RESULTS

As the slice shifted proximally, the VMA significantly increased (24.9 ± 8.5, 36.3 ± 8.8, 47.4 ± 11.8, 59.9 ± 14, 70.3 ± 13.7 degrees, respectively, p < 0.001 between all slices) and moved posteromedially from a medial direction. FAA (94.2 ± 7, 86.9 ± 9.2, 78.4 ± 9.7, 71.4 ± 9.8, 66.6 ± 10.5 degree, respectively, p < 0.001 between all slices) and FVA (100.6 ± 4.9, 98.3 ± 5.9, 93.7 ± 7.5, 88 ± 9.2, 81.1 ± 10.5 degrees, respectively, p < 0.001 between all slices) decreased and moved from a posterolateral to a posteromedial direction, while VMAD (35.4 ± 7.8, 24.1 ± 7.3, 14.3 ± 6, 8.4 ± 7, 6.2 ± 6.3 mm, respectively, p < 0.001 between all slices) and VMVD significantly decreased (42.7 ± 7.3, 32 ± 7.4, 22.4 ± 6.8, 14.5 ± 10.6, 8.7 ± 7.1 mm, respectively, p < 0.001 between all slices). The average vertical distance was 36 ± 9.3 mm (range 18.6-61.5 mm). The body height and the patellar length significantly affected the vertical distance.

CONCLUSION

The posterior border of the VM shifted posteromedially from distal to proximal and contacted the SFA at an average of 36 mm from the suprapatellar border. Surgeons should be aware of the risk of major vascular injury during exposure and osteotomy.

LEVEL OF EVIDENCE

Case series, Level IV.

Simultaneous Medial Patellofemoral Ligament and Medial Quadriceps Tendon-Femoral Ligament Reconstructions Using an Artificial Ligament for Lateral Patella Instability

Recent studies on the detailed anatomy of the medial patellar stabilizer have revealed that the medial patellofemoral ligament (MPFL) not only attaches to the patella but also has fibers that attach to the quadriceps muscle, known as the medial quadriceps tendon femoral ligament (MQTFL). Reconstruction of the medial stabilizer for patellar dislocation that includes both the MPFL and MQTFL may achieve better anatomical and physiological correction. In this Technical Note, we will describe a simultaneous reconstruction technique of the MPFL and MQTFL for patellar dislocation using an artificial ligament.

Potential risk of medial cortex perforation due to peg position of morphometric tibial component in unicompartmental knee arthroplasty: a computer simulation study

PURPOSE

The purpose of this study is to evaluate the risk of medial tibial cortical perforation in unicompartmental knee arthroplasty (UKA) due to peg positions on the tibial tray of the Persona Partial Knee (PPK).

METHODS

Preoperative CT images of 60 patients and 60 osteoarthritic knees (30 male and 30 female patients) were used. A tibial multiplanar reconstruction (MPR) image was reconstructed in preoperative planning software, and the implant was placed in a virtual osteotomy plane. In addition to PPK, Zimmer Unicompartmental Knee (ZUK) and TRIBRID (TBD) were used for evaluation. The horizontal distances from the medial tibial cortex to the anterior and posterior pegs (APCD/PPCD, respectively) were measured under neutral, 3-degree varus, 3-degree valgus and 2 mm distal positions. The differences between implants under the same positions and between positions using the same implants were compared. The percentage of total cases with APCD/PPCD of less than 3 mm and the perforation risk rate were calculated.

RESULTS

The APCD of PPK was significantly shorter at all positions except for the varus position of TBD. The PPCD of PPK was significantly shorter at all positions compared to ZUK and TBD. There were no cases with an APCD of less than 3 mm. Except for varus positions, the perforation risk rate of PPCD was significantly higher for PPK than the other two implants.

CONCLUSION

The posterior pegs of the PPK are located more medially than the other two implants, which may result in perforation of the medial tibial cortex during implantation. Surgeons should consider the risk involved in the type of implant used.

The prevalence and risk factors of pubic bone marrow edema in femoroacetabular impingement and hip dysplasia

Femoroacetabular impingement syndrome (FAIS) has been associated with osteitis pubis; however, it is still unclear whether hip dysplasia is associated with osteitis pubis. This study aimed to investigate (i) the incidence of pubic bone marrow edema (BME) on magnetic resonance imaging in symptomatic patients with FAIS, borderline developmental dysplasia of the hip (BDDH) and developmental dysplasia of the hip (DDH) undergoing hip arthroscopic surgery with labral preservation and (ii) the demographic and radiographic factors associated with pubic BME. A total of 259 symptomatic patients undergoing hip arthroscopic surgery between July 2016 and April 2019 were retrospectively reviewed and divided into three groups: FAIS (180 patients), BDDH (29 patients) and DDH (50 patients). Diffuse changes in the pubic bone adjacent to the pubic symphysis were labeled pubic BME, and the prevalence of their occurrence was examined. Multivariate logistic regression analysis was performed to identify factors involved in pubic BME, and odds ratios (ORs) for relevant factors were calculated. There was no significant difference in the prevalence of pubic BME among the three groups (20 [11.1%] of 180 FAIS patients, 6 [20.6%] of 29 BDDH patients and 7 [14%] of 50 DDH patients, P = 0.325). Multivariate logistic regression analysis showed that acetabular coverage was not associated with pubic BME, whereas younger age and greater alpha angle were still independent associated factors [age ≤26 years (OR, 65.7) and alpha angle ≥73.5° (OR, 4.79)]. Determining the possible association of osteitis pubis with cam impingement in dysplastic hips may provide insights toward a more accurate understanding of its pathophysiology.

Associations of LRP5 and MTHFR Gene Variants with Osteoarthritis Prevalence in Elderly Women: A Japanese Cohort Survey Randomly Sampled from a Basic Resident Registry

Objective

Osteoarthritis (OA) is a common and degenerative joint disorder in the elderly. A greater importance of understanding the relationship between genetic factors and OA prevalence has emerged with population aging. We therefore investigated the associations of several bone disease-related genetic variants with the prevalence of OA and osteoporosis in Japanese elderly women from the Obuse study cohort, which was randomly sampled from a basic town resident registry.

Methods and Results

In total, 206 female participants (mean ± standard deviation age: 69.7 ± 11.0 years) who completed OA, bone mineral density, and genotype assessments were included. The number of patients diagnosed as having knee/hip OA and osteoporosis was 59 (28.6%) and 30 (14.6%), respectively. Fisher’s exact testing revealed significant relationships between the minor T allele of LDL receptor related protein 5 (LRP5) rs3736228 and the prevalence of knee/hip OA and osteoporosis. The respective odds ratios (ORs) of the TT genotype for knee/hip OA and osteoporosis were 7.28 (95% confidence interval [CI] 2.22–28.08) and 5.24 (95% CI 0.95–26.98). An additional subgroup analysis for knee OA revealed that the frequency of the common C allele of methylenetetrahydrofolate reductase (MTHFR) rs1801133 had a statistically significant protective association with the prevalence of knee OA (OR 0.58, 95% CI 0.35–0.97).

Conclusion

In sum, the present study demonstrated significant associations of LRP5 rs3736228 and MTHFR rs1801133 with knee/hip OA and osteoporosis prevalences and knee OA prevalence, respectively, in Japanese elderly women. These results will help further the understanding of OA pathogenesis and related genetic risk factors.

Clinical outcome of a new remnant augmentation technique with anatomical double-bundle anterior cruciate ligament reconstruction: Comparison among remnant preservation, resection, and absent groups

Purpose

The aim of this study was to verify the effects of a new remnant augmentation technique with anatomical double-bundle anterior cruciate ligament (ACL) reconstruction for postoperative clinical scores, anterior stability and frequency of complications compared to remnant removal and cases with remnant defects.

Methods

The 105 patients who underwent anatomical double-bundle ACL reconstruction were divided into three groups. If the remnant was a Crain I-III type, remnant-preserving bone tunnel creation was attempted. After the creation of the bone tunnel, good continuity was maintained in 34 patients (preserved group). Due to lost continuity, the remnant was resected in 26 patients (resected group). No identifiable remnant continuity remained (Crain IV) in 45 patients (absent group). The Lysholm knee score, Tegner activity scale, International Knee Documentation Committee (IKDC) subjective score, anterior stability measured using the KT-1000 arthrometer at 2 years postoperatively, and frequency of complications were compared among the three groups. Univariate and multiple linear regression analysis were performed to clarify the factors affecting postoperative anterior stability.

Results

The Lysholm knee score, Tegner activity scale, IKDC subjective score, and frequency of complications were not significantly different among the groups. The mean side-to-side difference of anterior stability was significantly better in the preserved group (0.3 ± 1.6 mm) compared to the resected group (1.6 ± 2.3 mm, p = 0.003) and absent group (1.6 mm ± 1.7, p = 0.009). The multiple linear regression analysis showed remnant preservation significantly related to postoperative anterior stability.

Conclusion

Although there were no differences in clinical scores, the ACL reconstruction with new preservation technique showed good anterior stability and no difference in the frequency of complications.

Aperture elongation of the femoral tunnel on the lateral cortex in anatomical double-bundle anterior cruciate ligament reconstruction using the outside-in technique

In anatomical anterior cruciate ligament reconstruction surgery using the outside-in technique, the aperture of the femoral lateral cortex may become elliptical.Retrospective cross-sectional studyTo evaluate the extent of elliptical eccentricity in lateral apertures relative to aperture positioning and clinical failure rate in anatomical anterior cruciate ligament double-bundle reconstruction using outside-in technique.In 75 patients, the aperture elongation factor was defined as the ratio of the major axis of the elliptical aperture to the drill size. Using the lateral epicondyle as a reference point, the lateral femur was divided into sections by distance and angle, and the minimum area was evaluated to assess the relationship between the elongation factor and aperture position of the lateral cortex for each bundle. The incidence and associated clinical performance regarding cortical button migration were also investigated.Aperture elongation factors were 120.2 ± 13.3% and 120.0 ± 16.3% on the anteromedial (AM) and posterolateral (PL) sides, respectively. Femoral tunnel elongation was smallest when the entry point axis were both between 30 to 60° and distance was between 10 to 20 mm and 0 to 10 mm on the AM and PL sides, respectively. During the postoperative follow-up period, intra-tunnel migration was confirmed in 4 of 75 cases (5.3%). Fixation failure neither affected clinical scores nor knee laxity.Areas of minimum elongation for each bundle on both AM and PL sides were found anteroproximally to the lateral epicondyle and positioned near each other. Elongation did not directly affect the clinical outcome.Level of evidence grade: prognostic level III.

Plica syndrome after medial patellofemoral ligament reconstruction: a case report

A 16-year-old female with a history of left recurrent patellar dislocation underwent medial patellofemoral ligament (MPFL) reconstruction surgery. Two months postoperatively, the patient presented with medial patellar pain. Left medial plica syndrome was suspected, and we performed a partial arthroscopic resection of the medial synovial plica. The symptom gradually improved after surgery. To the best of our knowledge, there are no reports that discuss the relationship between postoperative pain of MPFL reconstruction and synovial plica as found in this case report. Surgeons should be aware of the possibility that asymptomatic synovial plica could become symptomatic.

Anatomical Remnant-Preserving Double-Bundle ACL Reconstruction With a New Remnant Augmentation Technique

Anterior cruciate ligament (ACL) remnant preservation techniques have been recently introduced for covering the graft with remnant to improve the clinical results of ACL reconstruction. Several theoretical advantages exist for this technique; however, clinical results remain inconsistent and controversial. We have focused on the biomechanical function of the remnant and have been performing a new remnant-preserving reconstruction procedure that augments the graft with residual remnant. Preserving the structure and continuity of good-quality remnants may help maintain the early postoperative stress on the tendon graft, thereby providing a positive effect on remodeling. Although our concept is significantly different from previously reported remnant preservation techniques and has several pitfalls, the surgical technique that we outline in this report is simple and does not require specialized equipment. The procedure will also work more advantageously in preserving the residual mechanoreceptors in the remnant. We believe that this method can be a procedure with better results for patients with remnants that are in good condition.

The interrelationship between anterior cruciate ligament tibial footprint and anterolateral meniscal root insertions: Quantitative, morphological and positional analyses using three-dimensional computed tomography images

BACKGROUND

The purpose of this study was to evaluate quantitative, morphological and positional differences between the anterior cruciate ligament (ACL) tibial footprint and anterolateral meniscal root (ALMR) insertion and investigate an intraoperative landmark to estimate their boundaries.

METHODS

Thirty-three fixed human cadaveric knees were evaluated. After resecting the components, the anterior fiber (AF) and posterior fiber (PF) of ALMR, the tibial center of ACL bundles (anteromedial (AM) and posterolateral (PL) bundles) and ACL were marked. Insertion morphology was classified into three categories, and the distance and relative positional relationship between AF/PF insertions and the center of each attachment were measured on three-dimensional computed tomography images.

RESULTS

There was no significant difference between the AF of AM and ACL (P = 0.16), but both were significantly shorter than the AF of PL (both P < 0.001). There was no significant difference between the PF of ACL and PL (P = 0.99), which were significantly shorter than PF of AM (both P < 0.001). Morphology of the ACL tibial insertion was classified as follows: triangular, 15 knees (45.5%); oval, 18 knees (54.5%); none, C-shape. Quantitative and positional analyses showed that the AF insertion was significantly closer to AM and ACL centers in the oval type than in the triangular type. Excluding two cases, the AF/PF insertion was located laterally to the ML center of the medial and lateral intercondylar tubercles.

CONCLUSION

Proximity of ACL tibial footprint and ALMR varies by their footprint morphology. The medial and lateral intercondylar tubercles were useful landmarks for ALMR injury prevention.

S-1 and irinotecan plus bevacizumab versus mFOLFOX6 or CapeOX plus bevacizumab as first-line treatment in patients with metastatic colorectal cancer (TRICOLORE): a randomized, open-label, phase III, noninferiority trial

Background

Combination therapy with oral fluoropyrimidine and irinotecan has not yet been established as first-line treatment of metastatic colorectal cancer (mCRC). We carried out a randomized, open-label, phase III trial to determine whether S-1 and irinotecan plus bevacizumab is noninferior to mFOLFOX6 or CapeOX plus bevacizumab in terms of progression-free survival (PFS).

Patients and methods

Patients from 53 institutions who had previously untreated mCRC were randomly assigned (1 : 1) to receive either mFOLFOX6 or CapeOX plus bevacizumab (control group) or S-1 and irinotecan plus bevacizumab (experimental group; a 3-week regimen: intravenous infusions of irinotecan 150 mg/m2 and bevacizumab 7.5 mg/kg on day 1, oral S-1 80 mg/m2 twice daily for 2 weeks, followed by a 1-week rest; or a 4-week regimen: irinotecan 100 mg/m2 and bevacizumab 5 mg/kg on days 1 and 15, S-1 80 mg/m2 twice daily for 2 weeks, followed by a 2-week rest). The primary end point was PFS. The noninferiority margin was 1.25; noninferiority would be established if the upper limit of the 95% confidence interval (CI) for the hazard ratio (HR) of the control group versus the experimental group was less than this margin.

Result

Between June 2012 and September 2014, 487 patients underwent randomization. Two hundred and forty-three patients assigned to the control group and 241 assigned to the experimental group were included in the primary analysis. Median PFS was 10.8 months (95% CI 9.6-11.6) in the control group and 14.0 months (95% CI 12.4-15.5) in the experimental group (HR 0.84, 95% CI 0.70-1.02; P < 0.0001 for noninferiority, P = 0.0815 for superiority). One hundred and fifty-seven patients (64.9%) in the control group and 140 (58.6%) in the experimental group had adverse events of grade 3 or higher.

Conclusion

S-1 and irinotecan plus bevacizumab is noninferior to mFOLFOX6 or CapeOX plus bevacizumab with respect to PFS as first-line treatment of mCRC and could be a new standard treatment.

Clinical trials number

UMIN000007834.

Lateralization of the Tibial Tubercle in Recurrent Patellar Dislocation: Verification Using Multiple Methods to Evaluate the Tibial Tubercle

BACKGROUND

The tibial tubercle deviation associated with recurrent patellar dislocation (RPD) has not been studied sufficiently. New methods of evaluation were used to verify the extent of tubercle deviation in a group with patellar dislocation compared with that in a control group, the frequency of patients who demonstrated a cutoff value indicating that tubercle transfer was warranted on the basis of the control group distribution, and the validity of these methods of evaluation for diagnosing RPD.

METHODS

Sixty-six patients with a history of patellar dislocation (single in 19 [SPD group] and recurrent in 47 [RPD group]) and 66 age and sex-matched controls were analyzed with the use of computed tomography (CT). The tibial tubercle-posterior cruciate ligament (TT-PCL) distance, TT-PCL ratio, and tibial tubercle lateralization (TTL) in the SPD and RPD groups were compared with those in the control group. Cutoff values to warrant 10 mm of transfer were based on either the minimum or -2SD (2 standard deviations below the mean) value in the control group, and the prevalences of patients in the RPD group with measurements above these cutoff values were calculated. The area under the curve (AUC) in receiver operating characteristic (ROC) curve analysis was used to assess the effectiveness of the measurements as predictors of RPD.

RESULTS

The mean TT-PCL distance, TT-PCL ratio, and TTL were all significantly greater in the RPD group than in the control group. The numbers of patients in the RPD group who satisfied the cutoff criteria when they were based on the minimum TT-PCL distance, TT-PCL ratio, and TTL in the control group were 11 (23%), 7 (15%), and 6 (13%), respectively. When the cutoff values were based on the -2SD values in the control group, the numbers of patients were 8 (17%), 6 (13%), and 0, respectively. The AUC of the ROC curve for TT-PCL distance, TT-PCL ratio, and TTL was 0.66, 0.72, and 0.72, respectively.

CONCLUSIONS

The extent of TTL in the RPD group was not substantial, and the percentages of patients for whom 10 mm of medial transfer was indicated were small.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Acetabular Fossa May Not Be Located at the True Center of the Acetabulum: A Detailed Analysis Using Preoperative CT Images

BACKGROUND

The acetabular fossa is thought to be located in the center of the acetabulum, and acetabular reaming in total hip arthroplasty is conventionally performed in the center of the fossa. However, the actual location of the fossa and the influence that hypoplasia or deformity may have on the position of the fossa are unknown. We hypothesized that the fossa is located in the center of the acetabulum, regardless of hypoplasia or deformity.

METHODS

Fifty patients with normal hips (normal hip group), 50 patients with dysplasia who underwent rotational acetabular osteotomy (dysplastic hip group), and 46 patients with osteoarthritis who underwent total hip arthroplasty (osteoarthritic hip group) were evaluated by computed tomography (CT) imaging. On the horizontal plane that passes through the center of the femoral head, the center line of the acetabulum was defined as the perpendicular bisector of the anterior and posterior rims of the acetabulum. The angle and distance of the center of the acetabular fossa in relation to the center line of the acetabulum were evaluated; furthermore, the center position of the fossa from the anterior margin of the acetabulum was calculated as a ratio relative to acetabular size. A 1-way analysis of variance was performed to compare measurements among the 3 groups.

RESULTS

The center of the acetabular fossa was positioned anteriorly to the center line of the acetabulum in all 3 groups. The mean center angle of the acetabular fossa was 14.0° ± 3.8°, 15.2° ± 5.6°, and 14.9° ± 5.5° in the normal, dysplastic, and osteoarthritic hip groups, respectively (p = 0.33). The mean center distance of the acetabular fossa was 5.6 ± 1.8, 5.8 ± 2.3, and 6.1 ± 2.2 mm, respectively (p = 0.55). The mean center position of the acetabular fossa was 38.8% ± 3.3%, 38.5% ± 4.2%, and 38.3% ± 3.9%, respectively (p = 0.71).

CONCLUSIONS

The center of the acetabular fossa is positioned anteriorly to the center of the acetabulum, and the positioning is affected by neither dysplasia nor osteoarthritis. The preconception that the center of the acetabulum corresponds to the center of the acetabular fossa may risk eccentric reaming, possibly damaging the anterior wall.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Tibial Tunnel Positioning Technique Using Bony/Anatomical Landmarks in Anatomical Anterior Cruciate Ligament Reconstruction

Because various biomechanical studies and clinical results have shown the effectiveness of an anatomical approach for anterior cruciate ligament (ACL) reconstruction, this approach has become gradually commonplace to improve postoperative performance. Standard tunnel positioning methods with accuracy, reproducibility, and adaptability to varied concepts are essential for the success of anatomical ACL reconstruction. However, there were no standard tibial tunnel positioning methods to satisfy these conditions. This technical note reports our tibial tunnel positioning technique using bony and/or anatomical landmarks for anatomical ACL reconstruction.

Remnant-Preserving Tibial Tunnel Positioning Using Anatomic Landmarks in Double-Bundle Anterior Cruciate Ligament Reconstruction

PURPOSE

To assess (1) if 6 anatomic landmarks (ALs) could be arthroscopically confirmed with remnant preservation and (2) if creating tibial tunnels using these landmarks reduces individual variation and improves reproducibility in double-bundle anterior cruciate ligament (ACL) reconstruction.

METHODS

We retrospectively reviewed data of patients who chronologically underwent double-bundle ACL reconstruction by either referencing the footprint after remnant dissection (non-AL group) or subsequently with the ALs (AL group). Using operative videos, 3 independent observers judged whether they could confirm 6 ALs (medial intercondylar ridge, medial and lateral intercondylar tubercles, anterior horn of lateral meniscus, Parsons' knob, and L-shaped ridge) in 20 patients randomly selected from the AL group. We then compared tunnel positions between the 2 groups, measured from the anterior and medial borders of the proximal tibia and expressed as percentage of the total depth and width of the proximal tibia using 3-dimensional computed tomography.

RESULTS

One hundred four patients (non-AL group, n = 54; AL group, n = 50) were included. All 6 ALs were arthroscopically confirmed in most cases (89.7% to 100%). The mean percentages of the anteroposterior (AP) depth for anteromedial (AM) tunnel, mediolateral (ML) width for AM tunnel, AP depth for posterolateral (PL) tunnel, and ML width for PL tunnel, respectively, were 27.8% ± 6.6%, 46.7% ± 2.8%, 41.4% ± 7.3%, and 46.1% ± 2.6% for the non-AL group and 30.7% ± 4.5%, 45.7% ± 2.2%, 45.2% ± 4.5%, and 46.9% ± 2.1% for the AL group, revealing significantly less variation in the AL group compared with the non-AL group, excluding the ML width of the PL tunnel (P = .007, .046, .002, .209, respectively).

CONCLUSIONS

Six landmarks could be reliably confirmed in cases with remnant preservation, and creating tibial tunnels using these landmarks were reproducible and resulted in less individual variation.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

What Components Comprise the Measurement of the Tibial Tuberosity-Trochlear Groove Distance in a Patellar Dislocation Population?

BACKGROUND

The tibial tuberosity-trochlear groove distance is used as an indicator for medial tibial tubercle transfer; however, to our knowledge, no studies have verified whether this distance is strongly affected by tubercle lateralization at the proximal part of the tibia. We hypothesized that the tibial tuberosity-trochlear groove distance is mainly affected by tibial tubercle lateralization at the proximal part of the tibia.

METHODS

Forty-four patients with a history of patellar dislocation and forty-four age and sex-matched controls were analyzed with use of computed tomography. The tibial tuberosity-trochlear groove distance, tibial tubercle lateralization, trochlear groove medialization, and knee rotation were measured and were compared between the patellar dislocation group and the control group. The association between the tibial tuberosity-trochlear groove distance and three other parameters was calculated with use of the Pearson correlation coefficient and partial correlation analysis.

RESULTS

There were significant differences in the tibial tuberosity-trochlear groove distance (p < 0.001) and knee rotation (p < 0.001), but there was no difference in the tibial tubercle lateralization (p = 0.13) and trochlear groove medialization (p = 0.08) between the patellar dislocation group and the control group. The tibial tuberosity-trochlear groove distance had no linear correlation with tubercle lateralization (r = 0.21) or groove medialization (r = -0.15); however, knee rotation had a good positive correlation in the patellar dislocation group (r = 0.62). After adjusting for the remaining parameters, knee rotation strongly correlated with the tibial tuberosity-trochlear groove distance (r = 0.69, p < 0.001), whereas tubercle lateralization showed moderate significant correlations in the patellar dislocation group (r = 0.42; p = 0.005).

CONCLUSIONS

Because the tibial tuberosity-trochlear groove distance is affected more by knee rotation than by tubercle malposition, its use as an indicator for tibial tubercle transfer may not be appropriate.

CLINICAL RELEVANCE

Surgical decisions of tibial tubercle transfer should be made after the careful analysis of several underlying factors of patellar dislocation.

Intrameniscal Gouty Tophi in the Knee: A Case Report

CASE

We report a case of recurrent acute arthritis and restricted range of motion in the knee joint, with magnetic resonance imaging subsequently detecting a nodular lesion within the lateral meniscus. Knee arthroscopy and histology revealed that the lesion was intrameniscal gouty tophi. After arthroscopic synovectomy and excision of the tophi, the symptoms resolved and the patient remained symptom-free at two years of follow-up.

CONCLUSION

Surgeons should be aware of the presence of such pathology and consider arthroscopic surgery if the mechanical symptoms persist.

Early Postoperative Intratunnel Migration of an EndoButton After Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction: A Case Report

CASE

We report a rare case of early postoperative migration of an EndoButton following anatomic double-bundle anterior cruciate ligament reconstruction with use of the EndoButton for femoral fixation. Although secure fixation of the EndoButton was confirmed during the operation, one-week postoperative radiographs revealed an intratunnel displacement of the posterolateral EndoButton. We performed a reoperation and refixed the EndoButton to the surface of the femoral cortex; we also hooked and tied both ends of the sutures to make a knot in order to prevent remigration.

CONCLUSION

Orthopaedic surgeons should be aware that EndoButton displacement and migration could arise at an early postoperative stage.

Bony Landmarks of the Anterior Cruciate Ligament Tibial Footprint: A Detailed Analysis Comparing 3-Dimensional Computed Tomography Images to Visual and Histological Evaluations

BACKGROUND

Although the importance of tibial tunnel position for achieving stability after anterior cruciate ligament (ACL) reconstruction was recently recognized, there are fewer detailed reports of the anatomy of the tibial topographic footprint compared with the femoral side.

HYPOTHESIS

The ACL tibial footprint has a relationship to bony prominences and surrounding bony landmarks.

STUDY DESIGN

Descriptive laboratory study.

METHODS

This study consisted of 2 anatomic procedures for the identification of bony prominences that correspond to the ACL tibial footprint and 3 surrounding landmarks: the anterior ridge, lateral groove, and intertubercular fossa. In the first procedure, after computed tomography (CT) was performed on 12 paired, embalmed cadaveric knees, 12 knees were visually observed, while their contralateral knees were histologically observed. Comparisons were made between macroscopic and microscopic findings and 3-dimensional (3D) CT images of these bony landmarks. In the second procedure, the shape of the bony prominence and incidence of their bony landmarks were evaluated from the preoperative CT data of 60 knee joints.

RESULTS

In the first procedure, we were able to confirm a bony prominence and all 3 surrounding landmarks by CT in all cases. Visual evaluation confirmed a small bony eminence at the anterior boundary of the ACL. The lateral groove was not confirmed macroscopically. The ACL was not attached to the lateral intercondylar tubercle, ACL tibial ridge, and intertubercular space at the posterior boundary. Histological evaluation confirmed that the anterior ridge and lateral groove were positioned at the anterior and lateral boundaries, respectively. There was no ligament tissue on the intercondylar space corresponding to the intercondylar fossa. In the second investigation, the bony prominence showed 2 morphological patterns: an oval type (58.3%) and a triangular type (41.6%). The 3 bony landmarks, including the anterior ridge, lateral groove, and intertubercular fossa, existed in 96.6%, 100.0%, and 96.6% of the cases, respectively.

CONCLUSION

There is a bony prominence corresponding to the ACL footprint and bony landmarks on the anterior, posterior, and lateral boundaries.

CLINICAL RELEVANCE

The study results may help create an accurate and reproducible tunnel, which is essential for successful ACL reconstruction surgery.

Phase II trial of cetuximab plus irinotecan for FOLFOX and FOLFIRI-refractory patients with EGFR-positive advanced and/or metastatic colorectal cancer: Evaluation of the efficacy and safety based on KRAS mutation status (T- CORE0801)

573

Background: Activating mutation of the KRAS gene is a predictive biomarker for loss of efficacy to anti-EGFR antibody therapy. However, this was mainly established by the evidences of Caucasian studies. Then, this prospective study investigated the role of KRAS mutations on efficacy and safety to cetuximab plus irinotecan in Japanese patients with metastatic colorectal cancer (mCRC).

Methods: We conducted a prospective study to analyze objective response to cetuximab plus irinotecan in molecularly defined KRAS wild-type (WT) or mutant subgroups of chemotherapy-refractory mCRC. KRAS mutations were detected by direct sequence on DNA from formalin-fixed, paraffin-embedded tissue of patients treated in 11 centers in Japan. Additional EGFR related genes such as BRAF, PIK3CA etc. and antibody-dependent cellular cytotoxicity related polymorphism in FCγRIIa and RIIIa genes were also examined.

Results: Forty-three patients were enrolled. KRAS mutations were found in 31.7% of 41 eligible patients. Response rate (RR) to cetuximab plus irinotecan, the primary endpoint of the study, was 17.9% and 0% for the patients with tumor harboring WT and mutant KRAS, respectively. No significant differences in toxicity were observed between the KRAS WT and mutant groups. Detail statistical analyses are ongoing.

Conclusions: We confirmed that KRAS status is a useful predictive maker for the efficacy to cetuximab plus irinotecan therapy in Japanese mCRC patients, even though the response rate in the KRAS WT group was lower than expected.

[Table: see text]

A randomized pilot study comparing safety and efficacy of irinotecan plus S-1 (IRIS) plus bevacizumab (BV) and modified (m) FOLFIRI plus BV in patients (pts) with metastatic colorectal cancer (mCRC): First report of T-CORE0702

496

Background: Sequential combination with irinotecan (CPT-11) and S-1 (IRIS) is active and safe regimen against mCRC (ASCO2008, abstract #4107, T. Yoshioka et al. Br J Cancer 101: 1972-77, 2009). The aim of this prospective randomized pilot study was to compare safety (CTCAE v3.0, primary endpoint) and efficacy (RR and PFS, secondary endpoint) of IRIS with mFOLFIRI when these were used with BV.

Methods: Sixty pts with mCRC were randomized to compare 30 pts for IRIS+BV (CPT-11 150 mg/m2 infusion on day 1, S-1 80 mg/m2 orally on day 3-16, q3w) with 30 pts for mFOLFIRI+BV (CPT-11 150mg/m2). 57 pts (IRIS arm 29, mFOLFIRI arm 28) were evaluable. Most of them were treated as first-line therapy.

Results: Background of pts was well balanced among two arms. Although G3/4 hematological AEs profiles were similar between two arms, G2-4 neutropenia was significantly lower in IRIS arm than mFOLFIRI arm (56.6%, vs. 88.9%, p=0.01, χ2test). Among G3/4 nonhematological AEs, gastrointestinal toxicities were lower in IRIS arm than mFOLFIRI arm (anorexia: 3.5% vs. 17.9%, nausea: 0% vs. 7.1%, diarrhea: 6.9% vs. 14.3%, stomatitis: 0% vs. 3.6%). By χ2 test, nausea, vomiting and hair loss were significantly lower in IRIS arm than mFOLFIRI arm (p<0.05). GI-perforation, a BV-related severe AE, occurred in 2 pts only from mFOLFIRI arm and one of them was died as TRD. RRs (institutional evaluation) were 58.6% in IRIS (CR 2, PR 15, SD 11, and PD 1) and 55.1% in mFOLFIRI arm (CR 0, PR 16, SD 10, PD 2, and not evaluable 1). Our independent review committee will clarified definite RR and median PFS near future.

Conclusions: Our IRIS+BV regimen is well tolerated, effective and appears to be a promising choice for pts with mCRC.

[Table: see text]

Phase I/II study of sequential therapy with irinotecan and S-1 for metastatic colorectal cancer

Background:

Both irinotecan (CPT-11) and S-1 are active against colorectal cancer; however, as S-1 is a prodrug of 5-fluorouracil (5-FU), 5-FU and its metabolites might inhibit the antitumour effect of CPT-11. Therefore, we designed a sequential combination, in which CPT-11 infusion was given on day 1 and S-1 was given orally at 80 mg m⁻² per day on days 3–16 every 3 weeks.

Methods:

Twelve patients entered the phase I study, and the recommended doses were determined as a CPT-11 dose of 150 mg m⁻² and an S-1 dose of 80 mg m⁻².

Results:

In all, 36 patients entered the phase II study, of whom 4 and 16 had complete and partial responses. The overall response rate was 55.6% (95% confidence interval, 38.1–72.1%), and median progression-free survival was 7.7 months (95% confidence interval, 4.8–12.6 months). Grade 3 neutropenia was the most common haematological toxicity and occurred in 6.5% of 215 treatment courses. Grade 3 non-haematological toxicities included anorexia (1.4%) and diarrhoea (0.9%). There was no grade 4 toxicity of any kind.

Conclusion:

Our results suggest that this regimen is convenient, safe and promising, compared with conventional regimens for patients with metastatic colorectal cancer.

CONSEL: for assessing the confidence of phylogenetic tree selection

CONSEL is a program to assess the confidence of the tree selection by giving the p-values for the trees. The main thrust of the program is to calculate the p-value of the Approximately Unbiased (AU) test using the multi-scale bootstrap technique. This p-value is less biased than the other conventional p-values such as the Bootstrap Probability (BP), the Kishino-Hasegawa (KH) test, the Shimodaira-Hasegawa (SH) test, and the Weighted Shimodaira-Hasegawa (WSH) test. CONSEL calculates all these p-values from the output of the phylogeny program packages such as Molphy, PAML, and PAUP*. Furthermore, CONSEL is applicable to a wide class of problems where the BPs are available.

AVAILABILITY

The programs are written in C language. The source code for Unix and the executable binary for DOS are found at http://www.ism.ac.jp/~shimo/

CONTACT

shimo@ism.ac.jp

Evaluating hypotheses on the origin and evolution of the New Zealand alpine cicadas (Maoricicada) using multiple-comparison tests of tree topology

The statistical testing of alternative phylogenetic trees is central to evaluating competing evolutionary hypotheses. Fleming proposed that the New Zealand cicada species Maoricicada iolanthe is the sister species to the major radiation of both low-altitude and montane Maoricicada species. However, using 1,520 bp of mitochondrial DNA sequence data from the cytochrome oxidase subunit I, tRNA aspartic acid, and the ATPase subunit 6 and 8 genes, we inferred that both M. iolanthe and another low-altitude species, Maoricicada campbelli, are nested within the montane Maoricicada radiation. Therefore, we examined the stability of the inferred phylogenetic placement of these two species using the newly developed Shimodaira-Hasegawa test (SH test) implemented in a maximum-likelihood framework. The SH test has two advantages over the more commonly used Kishino-Hasegawa (KH) and Templeton tests. First, the SH test simultaneously compares multiple topologies and corrects the corresponding P: values to accommodate the multiplicity of testing. Second, the SH test is correct when applied to a posteriori hypotheses, unlike the KH test, because it readjusts the expectation of the null hypothesis (that two trees are not different) accordingly. The comparison of P: values estimated under the assumptions of both the KH test and the SH test clearly demonstrate that the KH test has the potential to be misleading when the issue of comparing of a posteriori hypotheses is ignored and when multiple comparisons are not taken into account. The SH test, in combination with a variety of character-weighting schemes applied to our data, reveals a surprising amount of ambiguity in the phylogenetic placement of M. iolanthe and M. campbelli.

Consistency of SINE insertion topology and flanking sequence tree: quantifying relationships among cetartiodactyls

Short interspersed nuclear elements (SINEs) have been used to generate unambiguous phylogenetic topologies relating eukaryotic taxa. The irreversible nature of SINE retroposition is supported by a large body of comparative genome data and is a fundamental assumption inherent in the value of this qualitative method of inference. Here, we assess the key assumption of unidirectional SINE insertion by comparing the SINE insertion-derived topology and the phylogenetic tree based on seven independent loci of five taxa in the order Cetartiodactyla (Cetacea + Artiodactyla). The data sets and analyses were largely independent, but the loci were, by definition, linked, and thus their consistency supported an irreversible pattern of SINE retroposition. Moreover, our analyses of the flanking sequences provided estimates of divergence times among cetartiodactyl lineages unavailable from SINE insertion analysis alone. Unexpected rate heterogeneity among sites of SINE-flanking sequences and other noncoding DNA sequences were observed. Sequence simulations suggest that this rate heterogeneity may be an artifact resulting from the inaccuracies of the substitution model used.

Appropriate likelihood ratio tests and marginal distributions for evolutionary tree models with constraints on parameters

We show how to make appropriate likelihood ratio tests for evolutionary tree models when parameters such as edge (internodes or branches) lengths have nonnegativity constraints. In such cases, under the null model of an edge length being zero, the marginal distribution of this parameter is proven to be a "half-normal", that is, 50% zero values and 50% the positive half of a normal distribution. Other constrained parameters, such as the proportion of invariant sites, give similar results. To make likelihood ratio tests between nested models, e.g., H(0): homogeneous site rates, and H(1): site rates follow a gamma distribution with variance 1/k, then asymptotically as sequence length increases, the distribution under H(0) becomes a mixture of chi distributions, in this case 50% chi(0), and 50% chi(1) (where the subscript denotes degrees of freedom, i.e. , not the usually assumed 100% chi(1); which leads to a conservative test). Such mixtures are sometimes called distributions. Simulations show that even with sequences as short as 125 sites, some parameters, including the proportion of invariant sites, fit asymptotic distributions closely.

Effects of phosphorus-containing calcium preparation (bone meal powder) and calcium carbonate on serum calcium and phosphorus in young and old healthy volunteers: a double-blinded crossover study

To evaluate the effects of bone meal powder (BEC) on calcium and phosphorus metabolism, a calcium absorption test was conducted using a preparation of calcium carbonate (CAC) as the control drug. A total of 12 healthy volunteers, consisting of 6 younger (aged 20-29 years, 3 men and 3 women) and 6 older (aged 60-69 years, 3 men and 3 women) persons, were subjected to a double-blinded crossover study. Serum calcium (s-Ca) level significantly increased to 105.3% +/- 1.9% (P < 0.01 vs the basal value; mean +/- SD) from the basal value in the BEC group and to 104.4% +/- 2.7% (P < 0.01) in the CAC group at 3h post load. Urinary excretions of calcium (u-Ca/glomerular filtration rate, u-Ca/GF) after BEC and CAC load rose to 226.6% +/- 154.5% (P < 0.05) and 211.1% +/- 148.0% (P < 0.05), respectively. Serum phosphorus (s-P) levels after BEC load increased to 110.0% +/- 15.1% (P < 0.05), whereas that after CAC load showed no significant change (99.3% +/- 7.9%). On the other hand, urinary excretion of phosphorus (u-P/GF) after CAC load decreased to 60.0% +/- 32.4% (P < 0.01) and that in the BEC group showed no significant change (92.5% +/- 49.5%). The increase in s-Ca led to decrease in serum intact parathyroid hormone (i-PTH) level [77.3% +/- 33.4% (P < 0.05) for BEC and 69.5% +/- 20.3% (P < 0.01) for CAC] although s-P was increased by the BEC load. The responses to BEC and CAC administration were compared in the younger and the older groups. The responses in the younger and the older group showed fundamentally the same trends and to the same extent. However, the changes in serum ionized calcium (i-Ca) and i-PTH levels at 1.5 h post load were significantly smaller in the older group than in the younger group (P < 0.01; P < 0.05). The increment in s-P level after BEC load in the older group was larger than that in the younger group. In conclusion, BEC can modulate not only calcium but also phosphorus metabolism in both younger and older subjects. Further investigations are required to evaluate the effects of BEC on bone density and safety for renal function in long-term observations.

A new combination chemotherapy with cis-diammine-glycolatoplatinum (Nedaplatin) and 5-fluorouracil for advanced esophageal cancers

OBJECTIVE

The efficacy of a new chemotherapeutic combination consisting of Cis-diammineglycolatoplatinum (Nedaplatin), a derivative of cisplatin (CDDP), and 5-fluorouracil (5FU) was evaluated in patients with advanced esophageal carcinomas.

METHODS

Nedaplatin was administered at a dose of 80 or 100 mg/m2 with 500 ml of saline by slow drip infusion for 120 minutes on day 1. 5FU at a dose of 350 or 500 mg/m2 was mixed with 1,000 ml of saline and administered by continuous infusion for 24 hours on days 1 to 5.

PATIENTS OR MATERIALS

This combination chemotherapy was tried in 17 patients with metastatic, recurrent, or bulky unresectable esophageal cancers. Of these, 15 evaluable patients received at least two courses of chemotherapy.

RESULTS

The response rates in assessable and all patients were 60% and 52.9%, respectively. Cases with lymph node and liver metastases, as well as primary lesions, showed excellent response to the therapy with positive response rates of 54.5% (6/11), 100% (5/5) and 58.4% (7/12), respectively. The median response duration was 7 (range 3 to 37+) months for patients who achieved a partial response. Adverse drug reactions were limited to three cases of grade 3 toxicity, including allergy, and decreased hemoglobin and platelets, which were well tolerated by the patients.

CONCLUSION

The present study thus indicated the combination chemotherapy of Nedaplatin and 5FU to be safe and efficacious for advanced esophageal cancer. Further investigations are clearly warranted.