Bone mineral density around the knee after open wedge high tibial osteotomy measured up to 24 months in 51 patients

PURPOSE

To evaluate bone mineral density (BMD) and radiographic and clinical outcomes of patients with varus knee osteoarthritis treated with open wedge high tibial osteotomy (OWHTO). We hypothesised that medial condyle BMD would decrease and lateral condyle BMD would increase after OWHTO.

METHODS

Overall, 51 patients (mean age: 65.3 years; female: 40, male: 11) treated with OWHTO were prospectively enrolled. Several angles using whole single-leg radiographs were measured preoperatively and up to 24 months postoperatively. Five square tibial regions of interest (ROI) located below the proximal tibia as T1-T5 from medial to lateral regions and two square femoral ROI as F1 and F2 from medial and lateral regions, respectively, were defined. M/L BMD ratio was used to define the medial-to-lateral condyle BMD ratio. Femoral condyle BMD (F1 and F2) around the knee, as well as lumbar spine, and ipsilateral and contralateral femoral neck BMD, were measured before OWHTO and 3, 6, 12 and 24 months after OWHTO using dual-energy X-ray absorptiometry. Furthermore, tibial condyle BMD (T1-T5) around the knee was measured before and 24 months after OWHTO. Clinical outcomes were evaluated using the Knee Society knee and function scores, the Knee Injury and Osteoarthritis Outcome Score, and the Lysholm score preoperatively and 24 months postoperatively. A power analysis was performed.

RESULTS

F1 BMD decreased by 19.2% from before to 3 months postoperatively. F2 BMD did not change up to 24 months after OWHTO. Femoral M/L BMD ratio decreased by 22.2% 3 months after OWHTO. T1 BMD and tibial M/L BMD ratio decreased, whilst T3, T4 and T5 BMD increased 24 months after OWHTO. Mean hip-knee-ankle angle (HKA) and weight-bearing line ratio were corrected from - 6.8° to 4.5° and 14.7 to 60.7%, respectively, postoperatively. Lumbar spine BMD did not change up to 12 months postoperatively. Ipsilateral femoral neck BMD decreased up to 6 months after OWHTO.

CONCLUSION

Medial femoral condyle BMD decreased rapidly within 3 months and continued to decrease up to 12 months, but lateral femoral condyle BMD did not change after OWHTO. BMD measurements around the knee condyle enabled the evaluation of the changes in stress distribution before and after OWHTO with accelerated rehabilitation.

LEVEL OF EVIDENCE

II.

Measurements of neutrino oscillation parameters from the T2K experiment using 3.6×1021 protons on target

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7 ( 16.3 ) × 10 20 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7 × 10 20 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin 2 θ 13 and the impact of priors on the δ CP measurement. Both analyses prefer the normal mass ordering and upper octant of sin 2 θ 23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin 2 θ 13 from reactors, sin 2 θ 23 = 0 . 561 - 0.032 + 0.021 using Feldman-Cousins corrected intervals, and Δ m 32 2 = 2 . 494 - 0.058 + 0.041 × 10 - 3 eV 2 using constant Δ χ 2 intervals. The CP-violating phase is constrained to δ CP = - 1 . 97 - 0.70 + 0.97 using Feldman-Cousins corrected intervals, and δ CP = 0 , π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2 σ credible level using a flat prior in δ CP , and just below 2 σ using a flat prior in sin δ CP . When the external constraint on sin 2 θ 13 is removed, sin 2 θ 13 = 28 . 0 - 6.5 + 2.8 × 10 - 3 , in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

Recent advances in the direct anterior approach to total hip arthroplasty: a surgeon's perspective

INTRODUCTION

The direct anterior approach (DAA) has its origins in the first and oldest approach for hip replacement in the literature, but at the same time it would not be fanciful to suggest its increasing popularity as the latest approach for hip replacement procedures, especially among younger surgeons. However, in a geographical context, the DAA is not considered the major approach in most countries. Moreover, the term DAA encompasses numerous variations in terms of technique.

AREAS COVERED

In this narrative review, we describe our recent experience of advances in the DAA in terms of improved techniques and devices, along with some of its disadvantages. Also, we express our perspective on its future application.

EXPERT OPINIONS

The DAA is established as one of exemplary approaches to THA. The use of fluoroscopy, the traction table, and appropriate soft tissue management has become essential in the DAA for a safe and trouble-free procedure with adequate patient comfort. With the combination of recent technologies such as robotics, three-dimensional preoperative planning, and artificial intelligence (AI)-based surgeon assist systems, we can look forward to the DAA being performed more efficiently in the future.

Can double-level osteotomy prevent patellofemoral osteoarthritis progression compared with open wedge high tibial osteotomy?

PURPOSE

To compare radiographic, clinical, and arthroscopic findings in patellofemoral (PF) osteoarthritis (OA) between open wedge high tibial osteotomy (OWHTO) and double-level osteotomy (DLO) with the same operative indication.

METHODS

After adjustment for patient age, and coronal alignment, 36 knees with OWHTO alone and 36 knees with DLO were compared. Radiographic, clinical, and arthroscopic findings were documented before osteotomy. Arthroscopic findings were observed 1 year after osteotomy, and clinical and radiographic findings were observed 2 years after osteotomy. Patellar height was evaluated using the Insall-Salvati (IS) ratio, Carton-Deschamps (CD) index, and Blackburne-Peel (BP) index. Lateral patellar tilt and patellar shift were measured. A power analysis was performed.

RESULTS

The postoperative CD and BP indices in the OWHTO group were lower than those in the DLO group (p < 0.001 and p = 0.001, respectively). The CD and BP indices in both groups significantly decreased postoperatively (all p < 0.001). Tilting angles in the OWHTO and DLO groups significantly decreased postoperatively (p < 0.001 and p = 0.002, respectively). There were no significant differences in American Knee Society scores, Kujala score, and the Knee Injury and Osteoarthritis Outcome Scores between both groups. The PF OA progression of the trochlear in the OWHTO group was higher than that in the DLO group (p = 0.002), and the PF OA progression of the patellar facet in the DLO group and anterior femoral condyle in both groups on the lateral side were higher than those on the medial side (p = 0.006, 0.032, and 0.041, respectively).

CONCLUSIONS

DLO decreased the rate of low patellar height compared with OWHTO. DLO decreased the rate of PF OA progression in the trochlea compared with OWHTO. There were no significant differences in clinical outcomes in both groups.

LEVEL OF EVIDENCE

Level III, case-control study.

The relationship between the ''Fujisawa point'' and anatomical femorotibial angle following simulated open wedge high tibial osteotomy

Background

We evaluated the relationship between the weight-bearing line (WBL) ratio and anatomical femorotibial angle (FTA) by simulated open wedge high tibial osteotomy (OWHTO). This study evaluated the correlation between the ‘‘Fujisawa point’’ and FTA, and identified factors which caused deviations between the two measurement methods. We hypothesized that the Fujisawa point corresponded with 170° of the FTA.

Methods

Preoperative antero-posterior full-length lower limb radiographs of 82 patients were obtained for the OWHTO to place the WBL ratio at a target of 62.5% of the width of the tibial plateau (Fujisawa point). The coronal alignment was measured pre- and post-planning. The patients were divided into two groups by the post-planning FTA: a correspondence group (168.5°≦FTA≦171.5°) and a non-correspondence group (FTA < 168.5°, 171.5° < FTA). The relationship between the Fujisawa point and the FTA was analyzed with multivariate regression analysis.

Results

The post-planning FTA was 169.8 ± 1.1° and within 170 ± 1.5° in 69 cases (84.1%) when the WBL ratio was 62.5%. The neck shaft angle was 128.1 ± 5.2° in the correspondence group, and 122.3 ± 6.3° in the non-correspondence group. The multivariate linear regression analysis revealed that the neck shaft angle was the only factor that predicted the correspondence of the Fujisawa point with the FTA at 170° (p = 0.006, odd 1.28).

Conclusions

The post-planning FTA converged at 170° when the WBL ratio passed through the Fujisawa point and the neck shaft angle was the only predictor.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05734-7.

Acetabular cartilage abnormalities in elderly patients with femoral neck fractures

INTRODUCTION

Both hemiarthroplasty (HA) and total hip arthroplasty (THA) are widely accepted surgical procedures for hip replacement following displaced femoral neck fractures. However, in cases involving an intact joint line before surgery, the choice between HA and THA remains debatable. This study investigated the prevalence of acetabular cartilage and labral abnormalities in elderly patients with femoral neck fractures.

METHODS

Thirty-seven patients underwent hip arthroplasty for femoral neck fractures between April 2020 and February 2021. After excluding 4 patients, 33 patients (6 men and 27 women; mean age = 82.2 [range = 67-98] years) with fractures in 12 left and 21 right hips were included. After femoral head removal during arthroplasty, the acetabulum was macroscopically examined for the presence of cartilage and labral lesions. Acetabular cartilage abnormalities were classified as either overall degeneration or partial damage according to the cartilage damage classification system.

RESULTS

Acetabular cartilage abnormalities, including overall degeneration or partial damage, were found in all hips (100%). Out of the 33 hips, overall degeneration, partial damage, and labral abnormalities were detected in 32 (96.9%), 16 (48.4%), and 9 (27.2%) hips, respectively.

DISCUSSION

In this study, most elderly patients with femoral neck fractures exhibited acetabular cartilage and labral abnormalities, which were already present at the time of surgery. Therefore, surgeons should carefully examine these abnormalities as they may impact postoperative outcomes such as pain and function.

AB0239 HOW SOLID MALIGNANCIES ARE DETECTED IN JAPANESE PATIENTS WITH RHEUMATOID ARTHRITIS

Background

According to a meta-analysis reported in 20151), among solid malignancies (cancers), only lung cancer was at an increased risk in patients with rheumatoid arthritis (RA) compared with the general population. A Japanese cohort study reported that the incidence of cancers in patients with RA treated with biological DMARDs was not significantly elevated compared to the Japanese general population2). However, in recent years, malignancy has been one of the major causes of death in Japanese patients with RA3). It has been reported that there was an increased incidence of malignancies in patients treated with tofacitinib compared to TNF-alpha inhibitors. Clinicians need to pay more attention to emerging malignancies.

Objectives

We explored how to detect cancer early in patients attending rheumatology outpatient clinics.

Methods

In this retrospective study, we studied 545 patients with RA who visited our rheumatology clinic between April 2011 and December 2021. Forty-five cases of cancer in 38 patients (31 women, 7 men) with RA were reviewed.

Results

Cancer types: 9 breast, 8 lung, 6 colon, 5 uterus, 4 stomach, 2 prostate, 2 pancreas and 9 others. Five female patients had metachronous or simultaneous double cancers and one male patient had metachronous triple cancers. The median age at diagnosis of 45 cancers was 72 years old (IQR 63–76.5) and the median duration of RA prior to cancer diagnosis was 10 years (IQR 5–20.5).

Lung: Seven cases were found by chest CT at the outpatient clinics; two at the start of bDMARDs and five during RA treatment.

Stomach and Colon: Two cases of four stomach cancers were discovered due to the progression of anemia. Both patients were at an advanced stage with distant metastasis and died 2 months after diagnosis. On the other hand, four of six colon cancers were detected by the fecal occult blood test, and three were in remission.

Of the 45 cases, only 8 cases were detected by cancer screening. In 15 cases, blood samples or imaging tests were the triggers cancer detection. Eight of the 15 cases were detected by routine examinations in the rheumatology outpatient clinic, but five cases were already in the advanced stage.

Table 1.

Forty-five cancers in 38 patients with rheumatoid arthritis

Site of cancer nClue to cancer diagnosis and prognosis at the final visit (death - under treatment - remission)noticing symptomsVarious tests in outpatient clinic symptoms(-)Cancer ScreeningBreast98(1-4-3)　1(0-0-1)Lung81(1-0-0)7(2-3-2)　Colon6　1(1-0-0)5(0-1-4)Stomach41(0-0-1)3(3-0-0)　Cervix uteri31(0-0-1)　2(0-0-2)Corpus uteri22(0-2-0)　　Pancreas2　2(0-2-0)　Prostate22(0-1-1)　　Skin*22(0-0-2)　　Oral/throat22(0-2-0)　　Duodenum11(0-0-1)　　Biliary tract11(0-1-0)　　Anus1　　1(0-0-1)Bladder1　1(0-0-1)　Brain1　1(0-1-0)　Total4521(2-10-9)15(6-6-3)9(0-1-8)

Conclusion

We have been performing cancer screening before RA treatment and performing routine blood, urine, and imaging tests to identify adverse effects. However, they cannot always find cancers at the early stage. Screening procedures for malignancy are strongly recommended4), but the consultation rates for breast and cervical cancer screening are lower in Japan than in European nations. We should encourage our patients to undergo usual age- and sex-appropriate cancer screening.

References

[1]Simon TA, et al. Incidence of malignancy in adult patients with rheumatoid arthritis: a meta-analysis. Arthritis Research and Therapy 2015; 17:212

[2]Harigai M, et al. Risk for malignancy in rheumatoid arthritis patients treated with biological disease-modifying antirheumatic drugs compared to the general population: A nationwide cohort study in Japan. Modern Rheumatology 2016; 26:642

[3]Nakajima A, et al. Mortality and cause of death in Japanese patients with rheumatoid arthritis based on a large observational cohort, IORRA. Scand J Rheumatol 2010; 39:360

[4]Baillet A, et al. Points to consider for reporting, screening for and preventing selected comorbidities in chronic inflammatory rheumatic disease in daily practice: a EULAR initiative. Ann Rheum Dis 2016; 75:965

Disclosure of Interests

None declared

Surgical treatment for a combined anterior cruciate ligament and posterior cruciate ligament avulsion fracture: A case report

BACKGROUND

Independent avulsion fractures with anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL) attachment are relatively common among tibial intercondylar eminence fractures, and their postoperative outcomes are generally favorable. Conversely, huge avulsion fractures of the intercondylar eminence containing the attachment site of both the ACL and the PCL are extremely rare, and the reported clinical outcomes are poor.

CASE SUMMARY

We describe a 30-year-old Japanese male's huge avulsion fracture of the intercondylar eminence of a tibia containing the attachment site of both the ACL and PCL, together with a complete tear of the medial collateral ligament and a partial tear of both the medial and lateral menisci caused by a fall from a high place. All of these injuries were treated surgically, with anatomical reduction and stable fixation. The limb function at 1 year post-surgery was excellent (Lysholm score: 100 points).

CONCLUSION

Although this patient's complete surgical repair was complex, it should be performed in similar cases for an excellent final clinical outcome.

Massive calcification around large joints in a patient subsequently diagnosed with adult-onset hypophosphatasia

We report a 64-year-old Japanese woman with a history of progressive loss of motor function and painful swelling of large joints. At the age of 54, profound calcification appeared around the shoulder and hip joints, which did not heal after repeated surgical resections. Iliac bone biopsy revealed osteomalacic changes. Laboratory data showed low serum alkaline phosphatase (ALP) activity and a high urine phosphoethanolamine (PEA) concentration with normal serum calcium, phosphate, and fibroblast growth factor 23 (FGF23) levels. Subsequent genetic analysis of the ALPL gene confirmed the diagnosis of hypophosphatasia (HPP) with the identification of a heterozygous single nucleotide deletion, c.1559delT (p.Leu520ArgfsX86). We started a mineral-targeted enzyme replacement therapy, asfotase alfa (AA), to treat the patient's musculoskeletal symptoms. A follow-up bone biopsy after 12 months of AA treatment showed improvement of osteomalacia. Calcified deposits around the large joints were unchanged radiographically. To our knowledge, this is the first report of a patient with an adult-onset HPP who presented with profound calcification around multiple joints. Nonspecific clinical signs and symptoms in patients with adult-onset HPP often result in delayed diagnosis or misdiagnosis. We propose that bone biopsy and genetic analysis should be considered along with laboratory analysis for all patients with ectopic calcification around joints of unknown etiology for accurate diagnosis and better treatment.

Adequate Protein Intake on Comprehensive Frailty in Older Adults: Kyoto-Kameoka Study

OBJECTIVES

Defining an adequate protein intake in older adults remains unresolved. We examined the association between calibrated protein intake and comprehensive frailty by sex in the Kyoto-Kameoka study.

DESIGN

Cross-sectional study of baseline data.

SETTING AND PARTICIPANTS

The study included 5679 Japanese participants aged 65 years or older.

METHODS

Calibration coefficients were estimated from food frequency questionnaires and 7-day dietary records as a reference. Comprehensive frailty was evaluated using the 25-item Kihon Checklist (KCL) and defined as a total KCL score of ≥7points. Sex-specific calibrated protein intakes were presented as % of energy, per kg of actual body weight (BW), and per kg of ideal BW.

RESULTS

Multiple logistic regression analysis showed that calibrated protein intake is inversely associated with comprehensive frailty. The association between protein intake and comprehensive frailty was also evaluated using curve fitting with non-linear regression, a weak U-shaped association was found in males and an L-shaped association in females. Men had a low prevalence of frailty at a calibrated protein intake of 15-17% energy from protein, 1.2 g/kg actual BW/day, or 1.4 g/kg ideal BW/day, and women had a low prevalence of frailty at 17-21% energy from protein or 1.6 g/kg ideal BW/day, with the prevalence of frailty remaining unchanged at higher protein intakes. Meanwhile, the inverse relationship between protein intake per ABW and frailty showed a gradual decrease at 1.4 g/kg ABW/day for protein in women.

CONCLUSIONS AND IMPLICATIONS

A non-linear relationship was found between calibrated protein intake and frailty, with a U-shaped association in men and an L-shaped association in women. Adequate protein intake in healthy Japanese older adults was higher than the current recommended daily allowance.

Medialization of the mechanical axis of the tibia is related to lateralization of the tibial tuberosity in knee osteoarthritis

PURPOSE

To determine whether medialization of the proximal tibia due to a varus deformity is related to lateralization of the tibial tuberosity in varus knee osteoarthritis (OA).

METHODS

A total of 120 knees that underwent osteotomies around the knee for varus knee OA were enrolled. Mechanical medial proximal tibial angle (mMPTA) was measured on radiographs. The angle between the mechanical and anatomical axes of the tibia (angle MA) and the distance between the centre of the tibial plateau and the anatomical axis (distance MA) were measured in the coronal plane on computed tomography images. The tibial tuberosity-posterior cruciate ligament (TT-PCL) distance, the distance between the midpoint of the tibial tuberosity and the centre of the tibial plateau (TT-centre distance), and the angle between the line through the midpoint of the tibial tuberosity and the centre of the tibial plateau and the anteroposterior axis (TT-centre angle) were measured in the axial plane. The correlations of these parameters were evaluated.

RESULTS

mMPTA correlated negatively with angle MA (r = -0.37, P < 0.01) and distance MA (r = -0.55, P < 0.01). Angle MA and distance MA correlated with TT-PCL distance (r = 0.39, P < 0.01, r = 0.42, P < 0.01), TT-centre distance (r = 0.35, P < 0.01, r = 0.38, P < 0.01) and TT-centre angle (r = 0.36, P < 0.01, r = 0.36, P < 0.01).

CONCLUSIONS

Medialization of the proximal tibia due to a varus deformity may induce lateralization of the tibial tuberosity.

Primary bone adult T cell lymphoma with multiple skeletal lesions and debilitating painful osteolysis: a case report

There have been only a limited number of reports on primary adult T cell lymphoma/leukemia (ATL) in the bone. This is a case report of a 75-year-old patient initially reporting multiple bone pains that were attributed to osteolytic ATL. The patient developed spontaneous chest/back pain and visited a local hospital. Laboratory tests showed high levels of alkaline phosphatase (ALP), and computed tomography (CT) revealed skeletal lesions with osteolysis. Although multiple myeloma was initially suspected, the results of bone marrow aspiration and bone biopsy were inconsistent. After he was referred to our hospital, mild hypercalcemia (10.4 mg/dL) with low-normal intact parathyroid hormone (PTH) (27 pg/mL), low parathyroid hormone-related protein (PTHrP), and elevated 1,25-dihydroxy vitamin D (1,25OH₂D) levels (136 pg/mL) narrowed the differential diagnosis down to lymphomatous and granulomatous diseases, and then, the high serum soluble IL-2 receptor (3,450 U/mL) and the flower cells recognized in the peripheral blood sample suggested the involvement of ATL. Finally, the reevaluation of the iliac bone biopsy sample led us to the histological diagnosis of ATL infiltration in the bone. The subsequent two courses of chemotherapy in addition to denosumab resulted in an objective partial metabolic response indicated in 18-fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). Although very rare, the bone involvement of ATL could be used for the differential diagnosis for local osteolytic bone pain in addition to multiple myeloma and metastatic bone diseases.

Efficacy and safety of abiraterone acetate plus prednisolone in patients with early metastatic castration-resistant prostate cancer who failed first-line androgen-deprivation therapy: a single-arm, phase 4 study

Aim

The aim was to evaluate the efficacy and safety of abiraterone acetate plus prednisolone in patients with chemotherapy-naïve early metastatic castration-resistant prostate cancer who failed first-line androgen deprivation therapy.

Methods

Patients with early metastatic castration-resistant prostate cancer with confirmed prostate-specific antigen progression within 1-year or prostate-specific antigen progression without having normal prostate-specific antigen level (<4.0 ng/mL) during first-line androgen deprivation therapy were enrolled and administered abiraterone acetate (1000 mg) plus prednisolone (10 mg). A minimum of 48 patients were required according to Simon’s minimax design. The primary endpoint was prostate-specific antigen response rate (≥50% prostate-specific antigen decline by 12 weeks), secondary endpoints included prostate-specific antigen progression-free survival and overall survival. Safety parameters were also assessed.

Results

For efficacy, 49/50 patients were evaluable. Median age was 73 (range: 55–86) years. The median duration of initial androgen deprivation therapy was 32.4 (range: 13.4–84.1) weeks and 48 patients experienced prostate-specific antigen progression within 1-year after initiation of androgen deprivation therapy. prostate-specific antigen response rate was 55.1% (95% confidence interval: 40.2%–69.3%), median prostate-specific antigen–progression-free survival was 24.1 weeks, and median overall survival was 102.9 weeks (95% confidence interval: 64.86 not estimable [NE]). Most common adverse event was nasopharyngitis (15/50 patients, 30.0%). The most common ≥grade 3 adverse event was alanine aminotransferase increased (6/50 patients, 12.0%).

Conclusions

Abiraterone acetate plus prednisolone demonstrated a high prostate-specific antigen response rate of 55.1%, suggesting tumor growth still depends on androgen synthesis in patients with early metastatic castration-resistant prostate cancer. However, prostate-specific antigen–progression-free survival was shorter than that reported in previous studies. Considering the benefit–risk profile, abiraterone acetate plus prednisolone would be a beneficial treatment option for patients with chemotherapy-naive metastatic prostate cancer who show early castration resistance.

Open-wedge high tibial osteotomy using intraoperative control of joint line convergence angle with reference to preoperative supine radiograph

INTRODUCTION

Preoperative supine joint line convergence angle (JLCA) correlates with postoperative standing JLCA. Here, we compared the radiographic and clinical outcomes of knees with preoperative JLCAs of ≥ 4° and < 4° in open-wedge high tibial osteotomy (OWHTO). We hypothesized that the postoperative coronal alignment in both groups would not be affected by a change in JLCA if this change could predict before surgery.

MATERIALS AND METHODS

Eighty-four patients with medial knee osteoarthritis who underwent OWHTO were enrolled retrospectively. A weight-bearing line (WBL) ratio of 62% and a JCLA equivalent to the preoperative supine JLCA were anticipated in preoperative planning. These were intraoperatively set using an alignment rod and a radiolucent protractor under fluoroscopy. Soft tissue correction was defined as correction angle minus bone correction. The participants with preoperative JLCAs of < 4° (low-JLCA group) and ≥ 4° (high-JLCA group) were compared.

RESULTS

No significant difference in the coronal alignment was found between the groups after OWHTO. No significant differences in correction angle or bone correction were found between the groups, but the soft tissue correction in the high-JLCA group was higher than that in the low-JLCA group after OWHTO (p = 0.013).

CONCLUSIONS

When we controlled intraoperative JLCA, the postoperative coronal alignment was not affected by the change in JLCA and the differences in soft tissue correction between the low-JLCA and high-JLCA groups. However, overcorrection compared with the target coronal alignment remained in both groups.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Coronal shaft bowing of the femur affects varus inclination of the surgical transepicondylar axis in varus knee osteoarthritis

PURPOSE

This study investigated the relationship between femoral shaft bowing and the orientation of the surgical transepicondylar axis (TEA) in the coronal plane in varus knee osteoarthritis (OA).

METHODS

A total of 82 knees scheduled to undergo total knee arthroplasty (TKA) for the treatment of varus knee OA were enrolled. The hip-knee-ankle angle (HKA) was measured preoperatively on anteroposterior whole-leg standing radiographs. The lateral angle between the TEA and the mechanical axis of the femur (MA-TEA) was measured in the coronal plane from preoperative computed tomography (CT) images. Femoral shaft bowing was measured on CT images. Pearson's correlation coefficient was used to examine the correlation of the MA-TEA with the HKA and femoral shaft bowing.

RESULTS

The MA-TEA correlated negatively with the HKA (r = - 0.321, P < 0.01) and positively with femoral shaft bowing (r = 0.415, P < 0.01).

CONCLUSIONS

The TEA changed to varus as femoral shaft bowing increased in patients with varus knee OA. This suggests that the TEA is not always the centre of the rotational axis of the femur after TKA. In addition, the TEA may not be useful as a consistent parameter in the coronal plane in patients with increasing femoral shaft bowing.

LEVEL OF EVIDENCE

III.

Use of traction table did not increase complications in total hip arthroplasty through direct anterior approach performed by novice surgeon

PURPOSE

The purpose of this study was to investigate the surgical outcomes of total hip arthroplasty (THA) through direct anterior approach (DAA) performed by beginners by comparing the outcomes after the introduction of DAA-THA between using a normal operating table and a traction table.

METHODS

The total subjects were 200 patients, there were 120 cases from the introduction of three surgeons using a normal table and 80 cases from two surgeons using a traction table. The surgical procedure was standardized, and a surgeon skilled in DAA entered the operating room and instructed the novice surgeons of DAA in all cases.

RESULTS

The mean operative time was no significant difference between the two groups (p = 0.093). The difference in slope of the operative time was no significant difference between the two groups (p value = 0.089). The mean fluoroscopy time and the mean blood loss were significant difference between the two groups (p < 0.05). The difference in slope of the fluoroscopy time and blood loss were significant difference between the two groups (p < 0.05). There were no intraoperative complications and no reoperations for any reason.

CONCLUSIONS

At the facility with a surgeon skilled in DAA, the use of a traction table in DAA did not increase the complication rate compared with the use of a normal operating table when the exclusion criteria for DAA were set and surgery was performed using intraoperative fluoroscopy under supervision by a skilled surgeon.

Observation of Coulomb-Assisted Nuclear Bound State of Ξ^{-}-^{14}N System

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21  MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

Rotational Changes in the Distal Tibial Fragment Relative to the Proximal Tibial Fragment at the Osteotomy Site after Open-Wedge High-Tibial Osteotomy

The present study is aimed at assessing the changes in tibial rotation at the osteotomy site after an open-wedge, high-tibial osteotomy (OWHTO) and analysing the factors that affect rotational changes in the distal tibial fragment relative to the proximal tibial fragment at the same site. This study involved 53 patients (60 knees; 16 males and 37 females) with medial osteoarthritis (OA) who underwent OWHTO and preoperative and 3-month postoperative computed tomography (CT) scans. Rotational angles of the distal tibia were measured using Stryker OrthoMap 3D by comparing preoperative and postoperative CTs. The mean rotational angle yielded an external rotation of 2.9° ± 4.8°. There were 17 knees with internal rotations, 37 knees with external rotations, and one knee with no rotation. The rotational angle significantly correlated with the resultant change in the femorotibial angle (correction angle) and the angle between the ascending and transverse osteotomy lines on the anterior osteotomised surface on which a flange was formed with the distal tibial osteotomised surface (flange angle). The flange angle affected the rotation, but it may have been affected by our surgical technique. The rotational angle did not significantly correlate with the change in the angle of the posterior tibial slope or body mass index. There were significant correlations between the rotational angle and correction angle (r = 0.42, p < 0.05). Additionally, the rotational angle correlated with the flange angle (r = -0.41, p < 0.05).

Varus inclination of the tibia is related to patellofemoral osteoarthritis in Japanese female patients with moderate knee osteoarthritis

PURPOSE

The aim of this study was to investigate whether the tibial tuberosity-trochlear groove (TT-TG) distance and lateral patellar tilt, which induce patellofemoral osteoarthritis (OA), are related to the coronal deformity of the lower limb in varus knee OA. It was hypothesized that varus inclination of the tibia was negatively correlated with the TT-TG distance and lateral patellar tilt in Japanese female patients with moderate knee OA.

METHODS

A total of 104 female patients (139 knees) scheduled to undergo knee osteotomy for varus knee OA were enrolled. The coronal lower limb alignment was measured on anteroposterior whole-leg radiographs. The TT-TG distance, patellar tilt angle, and the patellofemoral joint space were measured both medially and laterally on computed tomography images. The correlations between coronal lower limb alignment and the TT-TG distance or patellar tilt angle, and the correlations between the TT-TG distance or patellar tilt angle and patellofemoral joint space were evaluated.

RESULTS

The medial proximal tibial angle was negatively correlated with the TT-TG distance (r =  - 0.383, P < 0.01) and patellar tilt angle (r =  - 0.34, P < 0.01). Lateral patellofemoral joint space was negatively correlated with the TT-TG distance (r =  - 0.256, P = 0.002) and patellar tilt angle (r =  - 0.205, P = 0.016).

CONCLUSIONS

Varus inclination of the proximal tibia may induce lateralization of the tibial tuberosity and lateral patellar tilt. The tibial tuberosity lateralization and lateral patellar tilt may induce lateral patellofemoral OA in patients with varus knee OA.

LEVEL OF EVIDENCE

III.

Suppression of gastric acid secretion decreased cardiovascular events independent of severe bleeding events in patients after percutaneous coronary intervention – sub-analysis from multicenter registry

Background

Suppression of gastric acid secretion by proton-pump inhibitor (PPI) or potassium-competitive acid blocker (P-CAB) has recently been developed as a standard strategy for preventing gastrointestinal bleeding for patients receiving antiplatelet therapy after percutaneous coronary intervention (PCI). However, there has been limited evidences on the association between PPI/P-CAB administration and adverse cardiovascular events in patients undergoing PCI.

Purpose

We aimed to evaluate the prognostic impact of the prescription of PPI/P-CAB on clinical outcomes in patients after PCI.

Methods

This study is a subanalysis from the TWINCRE registry that is a multicentral prospective cohort including patients who underwent PCI at 12 hospitals in Japan between 2017 and 2019. Among registered patients, we ultimately evaluated 1,428 patients who were followed-up. They were divided into two groups by the prescriptions of PPI or P-CAB at discharge for the index PCI; the PPI/P-CAB group (n=1,023), and the Non-PPI/P-CAB group (n=407). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE) including death, acute coronary syndrome, stent thrombosis, hospitalization due to heart failure and ischemic stroke. Secondary endpoints was major bleeding events defined BARC3, 4 and 5.

Results

The average age of the study population was 70.3 years and 80.3% were male. Baseline clinical profiles were comparable between the groups, except that the PPI/P-CAB group included significantly higher rate of patients who had history of prior PCI (28.4% vs 18.7%, P=0.02). Additionally, there was no significant difference in the duration of dual antiplatelet therapy between the PPI/P-CAB group and Non-PPI/P-CAB group (average duration; 287±8 vs. 285±8 days, P=0.66). Overall, MACCE was developed in 132 patients (9.3%), and bleeding event was observed in 24 patients (1.7%) during 574 days of median follow-up period. Kaplan-Meier analysis showed that patients in the PPI/P-CAB group had a significantly lower rate of MACCE than those in the Non-PPI/P-CAB group (Log-rank test, p=0.0003, Figure 1A). Multivariate Cox regression analysis revealed that the prescription of PPI/P-CAB still was independently associated with the primary endpoint (hazard ratio 0.532, 95% confidence interval 0.369–0.766, p=0.0007), even after the adjustment by diverse covariates. Whereas, there was no significant difference in the bleeding event (p=0.64, Figure 1B).

Conclusion

PPI or P-CAB therapy was associated with better clinical outcomes after PCI, independent of the incidences of severe bleeding events.

Figure 1

Funding Acknowledgement

Type of funding source: None

Correction to: Pre-operative templating in THA. Part II: a CT-based strategy to correct architectural hip deformities

The original version of this article unfortunately contained a mistake. The spelling of the Geert Pagenstert name was incorrect.

Nasal absorption enhancement of protein drugs independent to their chemical properties in the presence of hyaluronic acid modified with tetraglycine-L-octaarginine

Our previous mouse studies demonstrated that mean bioavailability of exendin-4, which is an injectable glucagon-like peptide-1 (GLP-1) analogue whose molecular weight (Mw) and isoelectric point (pI) are ca. 4.2 kDa and 4.5, respectively, administered nasally with poly(N-vinylacetamide-co-acrylic acid) (PNVA-co-AA) bearing D-octaarginine, which is a typical cell-penetrating peptide, was 20% relative to subcutaneous administration even though it was less than 1% when exendin-4 alone was given nasally. The studies also revealed that the absorption-enhancing ability of D-octaarginine-linked PNVA-co-AA for exendin-4 was statistically equivalent to that of sodium salcaprozate (SNAC), which is an absorption enhancer formulated in tablets of semaglutide approved recently as an orally available GLP-1 analogue. From a perspective of clinical application of our technology, we have separately developed hyaluronic acid modified with L-octaarginine via a tetraglycine spacer which would be degraded in biological conditions. The present study revealed that tetraglycine-L-octaarginine-linked hyaluronic acid enhanced nasal absorption of exendin-4 in mice, as did D-octaarginine-linked PNVA-co-AA. There was no significant difference in absorption-enhancing abilities between the hyaluronic acid derivative and SNAC when octreotide (Mw: ca. 1.0 kDa, pI: 8.3) and lixisenatide (Mw: ca. 4.9 kDa, pI: 9.5) were used as a model protein drug. On the other hand, SNAC did not significantly enhance nasal absorption of somatropin (Mw: ca. 22.1 kDa, pI: 5.3) when compared with absorption enhancer-free conditions. Substitution of SNAC with tetraglycine-L-octaarginine-linked hyaluronic acid resulted in a 5-fold increase in absolute bioavailability of somatropin with statistical significance. It appeared that pI hardly ever influenced absorption-enhancing abilities of both enhancers. Results indicated that our polysaccharide derivative would be a promising absorption enhancer which delivers biologics applied on the nasal mucosa into systemic circulation and was of greater advantage than SNAC for enhancing nasal absorption of protein drugs with a larger Mw.

P1496Impact of electrical reverse remodeling by cardiac resynchronization therapy on adverse cardiac events in patients of heart failure with reduced ejection fraction

Background

Recently, structural reverse remodeling (SRR) and electrical reverse remodeling (ERR) after cardiac resynchronization therapy (CRT) have been reported in patients of heart failure with reduced ejection fraction (HFrEF). However the relationship between ERR and subsequent adverse cardiac events is still unknown. We aimed to elucidate the impact of ERR after CRT on the occurrence of heart failure events and ventricular arrhythmias.

Methods

A total of 36 HFrEF patients who underwent newly CRT implantation were investigated retrospectively. The intrinsic QRS duration (iQRSd) had been recorded before and more than 6 months after CRT implantation. Biventricular pacing was temporarily turned off during measurement of iQRSd. ERR was defined as positive shortening of iQRSd and SRR was defined as reduction of left ventricular end systolic volume by more than 15% after CRT implantation. The primary endpoint was a composite of all cause death, heart failure hospitalizations and ventricular tachyarrhythmia events.

Results

ERR was observed in 17 patients (47.2%) and SRR in 22 patients (61.1%). The group with ERR included more patients with lower NYHA class prior to CRT and patients with SRR. The primary endpoint was observed in 15 patients (51.4 %) for a median of 181 [63, 367] days during follow-up. Kaplan-Meier analysis revealed that the group without ERR was poor prognosis compared with the group with ERR (p = 0.022, Log-rank test).

Conclusion

Patients of HFrEF with ERR after CRT may have fewer adverse cardiac events such as worsening heart failure or ventricular arrhythmia events from this short-term study.

Abstract Figure. Adverse cardiac events and ERR

THU0293 PREDICTORS OF LONG-TERM THERAPY WITH GLUCOCORTICOID IN POLYMYALGIA RHEUMATICA

Background:

Polymyalgia rheumatica (PMR) is a common inflammatory condition of elderly persons. Clinical symptoms respond to low-dose glucocorticoids (GC), but treatment is often required for several years. 2015 EULAR/ACR recommendations1)recommend considering early introduction of methotrexate (MTX) in addition to GC, particularly in patients at a high risk for relapse and/or prolonged therapy. However, risk factors for prolonged therapy are not clear yet.

Objectives:

We investigated predictive factors which corresponded to the long-term GC therapy.

Methods:

This was a retrospective study in a single general hospital in Japan. We reviewed the medical records of the Japanese patients with PMR between April 2011 and January 2020. Diagnosis of PMR was based on Bird’s criteria or 2012 EULAR/ACR Classification Criteria2). All patients were treated with prednisolone (PSL), according to the BSR and BHPR guidelines3), for more than 6 months. Patients treated with MTX and accompanied by the giant cell arteritis were excluded from this study. Relapse was defined as the reappearance of symptoms associated with elevated C-reactive protein (CRP) levels in patients receiving GC that required an increase in GC dose. Remission was defined as the absence of clinical symptoms and normal CRP with discontinuation of GC. We compared the clinical findings, laboratory data at baseline and clinical course between those who achieved remission within 2 years (early-remission group) and those who required GC therapy for more than 2 years (long-therapy group). Comparisons between groups were made using Student’s t-test and chi-square test (IBM SSPE statistics version 26). This study was approved by the ethics committee of Tokyo Medical University (T2019-0079).

Results:

As of January 2020, 89 patients have been treated with PSL for more than 6 months. 50 patients have achieved a remission, 29 were undergoing treatment, and 10 have transferred to other hospitals or died (Table 1). The median time required for the patients to achieve remission was 16 months (Interquartile Range 12-21). After one-year GC therapy, remission was achieved in 14% (11/77), 66% (41/62) after 2-year, 84% (47/56) after 3-year, and 91.0% (49/54) after 4-years. Forty-one patients, who achieved remission within 2 years, were included in the early-remission group. Twenty-one were included in the long therapy group (Table 1). There were no differences in sex, age at onset, body mass index, clinical features, and serum albumin at diagnosis. Serum CRP of long-therapy group was significantly higher than those of the early-remission group (Table 2). Mean relapse times in the full follow-up times were 0.4 in the early-remission group and 3.1 in the long-therapy group. Multivariate logistic regression analysis showed that history of relapse till 6 months was significant predictors of the long-term GC therapy (odds ratio, 6.48; 95%CI 1.44-29.12).

Conclusion:

The remission rates of our study are lower than those of the previous reports. We have tapered GC gradually according to the BSR and BHPR guidelines3). However, some patients need the long-term therapy for more than 2 years. We might consider additional MTX therapy in patients who experience a relapse during the first six months.

References:

[1]Dejaco C, et al. 2015 recommendations for the management of polymyalgia rheumatica: a European League against Rheumatism/American College of Rheumatology collaborative initiative. Ann Rheum Dis 2015; 74:1799-1807.

[2]Dasgupta B, et al: 2012 provisional classification criteria for polymyalgia rheumatica: a European League against Rheumatism/American College of Rheumatology collaborative initiative. Ann Rheum Dis 2012;71: 484-492.

[3]Dasgupta, B, et al. BSR and BHPR guidelines for the management of polymyalgia rheumatica. Rheumatology 2010; 49:186-190.

Disclosure of Interests:

None declared

Joint line convergence angle predicts outliers of coronal alignment in navigated open-wedge high tibial osteotomy

INTRODUCTION

Using a navigation system in open-wedge high tibial osteotomy (OWHTO) has higher accuracy than using the conventional method. However, unintentional over- and under-correction still exist. This study aimed to compare various factors related to over- and under-correction and to assess their predictive factors in the preoperative radiographs.

MATERIALS AND METHODS

This study involved 96 knees. The difference in the hip-knee-ankle angle (HKA) between the intraoperative navigation system and postoperative radiograph was termed navigation correction loss (NCL). Knees with absolute values of NCL (|NCL|) ≦ 1.5° and |NCL| > 1.5° were categorised into acceptable (n = 46) and outlier (n = 50) groups, respectively. The differences in joint line convergence angle (JLCA) between varus and valgus radiographs, varus JLCA, valgus JLCA, standing JLCA and standing HKA were compared between the two groups. Clinical results were evaluated using the American Knee Society (AKS) scores.

RESULTS

The mean intraoperative HKA in the navigation system was - 3.8 ± 1.8°, and that in the postoperative standing radiograph was - 4.2 ± 2.5° (p = 0.033). Preoperative varus, valgus and standing JLCA were higher in the outlier group (p = 0.018, p = 0.020 and p = 0.001, respectively). Logistic regression analyses for preoperative factors of |NCL| ≦ 1.5° showed that standing JLCA was a determining factor, with an odds ratio of 1.334 (confidence interval was 1.087-1.637, p = 0.006). AKS score was higher in the acceptable group (p = 0.040) postoperatively.

CONCLUSIONS

Higher preoperative standing JLCA was the predictive factor of |NCL| > 1.5°. This factor reduced the rates of under- and over-correction and resulted in better AKS score in OWHTO.

P1353Echocardiographic predictor of sick sinus syndrome following catheter ablation of persistent atrial fibrillation

Funding Acknowledgements

Abbott Medical Japan, Medtronic Japan, Boston Scientific Japan, Biotronic Japan, Japan Life Line

Background / Introduction

Although sick sinus syndrome(SSS) can be associated with atrial fibrillation(AF), predictive factors of SSS following catheter ablation(CA) of persistent atrial fibrillation(perAF) are not well known.

Purpose

We investigated echocardiographic parameters to predict occurrence of SSS after restoration of sinus rhythm by CA for perAF patients.

Methods

Ninety-eight consecutive perAF patients from June 2014 to May 2018 treated with CA were retrospectively reviewed. Twelve patients(12%, SSS group) developed SSS after successful CA and 86 patients(88%, non-SSS group) did not. Baseline characteristics, blood exam, and echocardiographic findings(RA area size, LA area size, EF, etc) before AF CA were analyzed using Student’s t test, Mann-Whitney test, Chi-square test and Univariate analysis. Multivariate logistic analysis was then performed using those parameters. The atrial area size was calculated from 4 chamber view at the atrial end- systole.

Results

The multivariate analysis for predictive factors of SSS is shown in the table. Right atrium(RA) area could predict SSS(17.3 ± 4.8cm2 vs. 14.7 ± 3.6cm2, odds ratio 1.468; 95% confidence interval 1.088 to 1.981, p = 0.012). Gender (female) was also an independent predictor(4/12 (33%) vs. 8/86 (9%), odds ratio 39.832; 95% confidence interval 2.589 to 612.938, p = 0.008). The other echocardiographical findings(LA area size, EF, etc), baseline characteristics and blood exam results were not related to SSS after successful CA of perAF patients.

Conclusions

The large RA area size and gender (female) could predict SSS in perAF patients after restoration of sinus rhythm by successful CA. We may need to inform possible SSS after CA to female patients with a large RA before CA.

Multivariate Logistic analysis Total(N = 98) SSS group (N = 12) Non SSS group (N = 86) Odds ratio 95% CI P-value Age 64(58-69) 68(60-72) 63(57-69) 1.032 0.929-1.145 0.560 Gender/Female 12(12%) 4(33%) 8(9%) 39.832 2.589-612.938 0.008 CKD 27(28%) 6(50%) 21(24%) 1.264 0.179-8.945 0.814 BNP 91(53-180) 206(167-304) 82(48-169) 1.003 0.993-1.012 0.609 RDW 45.1 ± 3.9 46.4 ± 4.8 44.9 ± 3.8 1.242 0.971-1.588 0.085 RA area 15.1 ± 3.8 17.3 ± 4.8 14.7 ± 3.6 1.468 1.088-1.981 0.012 LA area 24.2(17.0-24.9) 24.4(17.7-26.3) 24.1(16.8-24.4) 0.967 0.803-1.165 0.726 Right atrium area and gender were the independent predictor of SSS in persistent atrial fibrillation patients after restoration of sinus rhythm

Relationship between lower limb torsion and coronal morphologies of the femur and tibia in patients with medial knee osteoarthritis

Background

To investigate the relationship between femoral or tibial torsion and hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), or mechanical medial proximal tibial angle (mMPTA) in patients with medial knee osteoarthritis (OA).

Methods

A total of 75 knees were enrolled. Femoral and tibial torsions were measured by superimposing the axial planes of computed tomography images. The relationship between femoral or tibial torsion and HKA, mLDFA, or mMPTA on radiographs was examined.

Results

The mean femoral torsion was 12.2 ± 8.5° internally; femoral internal and external torsions were observed in 70 and 5 knees, respectively. The mean tibial external torsion was 18.0 ± 7.4° externally; tibial external torsion was observed in all 75 knees. Femoral internal and tibial external torsions increased with lower mMPTA (r = 0.33, P = 0.003; r = − 0.32, P = 0.005, respectively) but were not related to HKA or mLDFA.

Conclusion

Femoral and tibial torsions were correlated with varus inclination of the proximal tibia in patients with medial knee OA.

Usefulness of glycated albumin as a predictor of mortality in chronic hemodialysis patients with diabetes: a multi-center, prospective cohort study

Background

The association of glycated albumin (GA) with mortality is unclear in chronic hemodialysis patients with diabetes. We investigated the usefulness of GA by comparing it with hemoglobin A1c (HbA1c) in this patient population.

Research design and methods

This was a multi-center, prospective cohort study of 841 Japanese chronic hemodialysis patients with diabetes. There were 235 women and 606 men included, with a mean age of 64 years. The primary and secondary endpoints were the incidence of all-cause and cause-specific mortality, respectively. The hazard ratios of GA and HbA1c for the endpoints were estimated using the values at baseline and during the study period.

Results

During the mean follow-up period of 3.1 years, there were 184 deceased cases, in which 30 and 154 resulted from atherosclerotic cardiovascular disease (ASCVD) and non-ASCVD, respectively. The hazard ratio for a 1% increase in GA was 1.033 (95% confidence interval 1.006–1.060, p = 0.017) for all-cause mortality with a statistical significance when GA was treated as a time dependent variable, but not when the baseline levels or the mean levels during the follow-up period were used in the analysis (p = 0.815 and 0.517, respectively). GA was a significant predictor for ASCVD-related mortality in the above 3 models, but was not for non-ASCVD mortality. Higher levels of HbA1c were only associated with ASCVD-related mortality when HbA1c was treated as a time-dependent variable.

Conclusions

GA may be useful compared to HbA1c for predicting all-cause and ASCVD-related mortality in Japanese patients with diabetes undergoing chronic hemodialysis.

Colorectal cancer treated by resection and extended lymphadenectomy: patterns of spread in left- and right-sided tumours

BACKGROUND

Whether tumour side affects the anatomical extent and distribution of lymph node metastasis in colon cancer is unknown. The impact of tumour side on the anatomical pattern of lymphatic spread in colon cancer was assessed.

METHODS

Patients with stage III colon cancer from a Japanese multi-institutional database who underwent extensive (D3) lymphadenectomy, which is similar in concept to complete mesocolic excision with central venous ligation, were divided into groups with right- and left-sided tumours. Based on location, mesenteric lymph nodes were categorized as paracolic (L1), intermediate (L2) or central (L3). The Kaplan-Meier method was used to evaluate disease-free survival (DFS) and overall survival (OS), and multivariable Cox models were used to evaluate the association between anatomical lymph node level, metastatic pattern and outcome.

RESULTS

A total of 4034 patients with stage III colon cancer (right 1618, left 2416) were included. Unadjusted OS was worse in patients with right colon cancer (hazard ratio 1·23, 95 per cent c.i. 1·08 to 1·40; P = 0·002), but DFS was similar. Right-sided tumours more frequently invaded L3 nodes than left-sided lesions (8·5 versus 3·7 per cent; P < 0·001). The proportion of patients with a skipped pattern of lymphatic spread was higher in right than in left colon cancer (13·7 versus 9·0 per cent; P < 0·001). In multivariable analysis, invasion of L3 nodes was associated with worse OS in left but not in right colon cancer. The presence of skipped metastasis was associated with worse DFS in left, but not right, colon cancer.

CONCLUSION

There are significant differences in the pattern of lymph node invasion between right- and left-sided stage III colon cancer, and in their prognostic significance, suggesting that tumour side may dictate the operative approach.

Pre-operative templating in THA. Part II: a CT-based strategy to correct architectural hip deformities

INTRODUCTION

Pre-operative templating for total hip arthroplasty (THA) remains inaccurate due to improper magnification and alignment. We aimed to describe an improved templating strategy using computed tomography (CT) to predict component sizes and offsets with greater accuracy.

MATERIALS AND METHODS

We analysed 184 CT images acquired for pre-operative templating of primary THA. We aimed to restore native (pre-arthritic) femoral offset and limb length, by raising the head center to the level of the templated cup center cranio-caudally, but maintaining the pathologic (pre-operative) head center medio-laterally (except in medialized hips). Acetabular offset (AO) and femoral offset (FO) were measured on pre-operative CT scans, during acetate templating, and on post-operative true antero-posterior radiographs.

RESULTS

The post-operative offsets were within ± 5 mm from templated estimates in 174 hips (91%) for AO, in 116 hips (61%) for FO, in 111 hips (58%) for GO, and in 134 hips (70%) for neck cut level. The post-operative hip architecture reproduced the templated hip architecture within ±5 mm in 77 hips (40%). The agreement between planned and post-operative parameters was moderate for stem size (0.57), cup size (0.62), AO (0.50), but fair for FO (0.45). The AO decreased in most arthritic types, notably in lateralized hips (6.6 mm), but remained unchanged in medialized hips. The FO increased in most arthritic types (1.8-3.1 mm) but remained unchanged in medialized and lateralized hips.

CONCLUSIONS

We described a strategy for pre-operative templating in THA. Despite the accuracy of CT, the authors found significant variations between planned and post-operative reconstructions, which suggest that pre-operative templating should only be used as an approximate guide.

Ultrasonic B-Line-Like Artifacts Generated with Simple Experimental Models Provide Clues to Solve Key Issues in B-Lines

We evaluated the influence of settings on an ultrasound machine on the configuration of a single B-line in a healthy model and analyzed the frequency spectrum. We also devised simple experimental models that generated B-line-like artifacts and evaluated the influence of the machine settings on the configuration. Visualization of B-lines was affected by the spatial compound imaging, the focal zone and the frequency. The spectra of both the B-line and non-B-line region at the same depth had the same center frequency and bandwidth. B-line-like artifact was generated by a spindle-shaped juice sac of a mandarin orange, an edible string-shaped glucomannan gel, glass beads and glass plates. Visualization of B-line-like artifacts was also affected by these machine settings. Our study indicated that the physical basis of some B-lines is multiple reverberations. B-line-like artifacts provide clues for solving key issues, such as the physical basis of B-lines, the sonographic-pathologic correlation in B-lines and the effects of machine settings.