Addition of preoperative ultrasound-guided suprascapular nerve block and axillary nerve block to parecoxib is more effective in early postoperative pain control following arthroscopic rotator cuff repair: a prospective randomized controlled study

PURPOSE

The purpose of the study was to prospectively compare the pain intensity and patient-reported outcomes (PROs) following arthroscopic rotator cuff repair (ARCR) between patients who received ultrasound-guided suprascapular nerve block (SSNB) and axillary nerve block (ANB) as well as preincisional parecoxib and patients who received preincisional parecoxib only.

METHODS

Sixty-one patients receiving ARCR between March 2020 and March 2021 were prospectively enrolled. They were randomly assigned to the peripheral nerve block group (group N, n=30) or control group (group C, n=31). Two patients from group C were excluded because of miscommunication. All patients were administered parecoxib 40 mg intravenously prior to induction of anesthesia. In group N, SSNB/ANB were performed after general anesthesia while no nerve block was performed in group C. The pain intensity was compared before the surgery, as well as immediately, 24 hours and 2 weeks after the surgery. PROs, including Oxford shoulder score, University of California-Los Angeles shoulder score and Single Assessment Numeric Evaluation score, were compared before and 6 months after the surgery.

RESULTS

The resting pain numerical rating scale (NRS) was significantly lower in group N (4.9 ± 3.1 vs. 7.6 ± 2.5, p<0.001) immediately after the surgery, but no difference was noted 24 hours after the surgery. The resting pain NRS 2 weeks after the surgery was significantly lower in group N (1.4 ± 1.6 vs. 2.7 ± 2.7, p=0.03), but the movement-evoked pain and night pain were similar. All PROs significantly improved 6 months after the surgery in both groups, but there was no difference between the 2 groups.

CONCLUSION

Addition of preoperative ultrasound-guided SSNB and ANB to parecoxib offered better resting pain control immediately and 2 weeks after ARCR, but there was no benefit for PROs 6 months after the surgery.

LEVEL OF EVIDENCE

Level 2 prospective randomized controlled trial.

Relationship between shoulder and elbow range of motion and ultrasonographic structural abnormalities in the elbow of Taiwanese high school baseball players

BACKGROUND

Ultrasonographic structural abnormalities are regarded as one of the risk factors of elbow injuries. Elbow injuries are commonly associated with decreased shoulder/elbow range of motion (ROM). The purpose of this study is to determine the relationship between shoulder/elbow ROM and elbow ultrasonographic structural abnormalities in Taiwan high school baseball players.

METHODS

A total of 533 Taiwan high school baseball players were enrolled. Physical examinations including measurements on shoulder/elbow ROM and elbow sonographic examinations were performed and recorded by professional physicians. The analyses were conducted in three subgroups according to their defensive position because the training programs were different. All players pooled, pitchers-only, and fielders-only, due to several demographic differences among these subgroups. In all the subgroups, univariate analyses were conducted separately for participants with and those without elbow ultrasonographic structural abnormalities, and then multivariate analyses were conducted to identify factors significantly related. The odds ratios (ORs) were used to estimate the risk of elbow ultrasonographic structural abnormalities.

RESULTS

Demographic data showed that pitchers had taller body height (P < 0.001) and greater elbow flexion/extension ROM (P < 0.001). When all players were pooled, significant risk factors included started playing baseball at an younger age (OR = 1.202; 95% CI = 1.064-1.357; P = 0.003), longer experience of official baseball (OR = 1.154; 95% CI = 1.038-1.283; P = 0.008), lower total shoulder rotation angle (OR = 1.007; 95% CI = 1.000-1.014; P = 0.050), and less total elbow arm angle (OR = 1.052; 95% CI = 1.017-1.088; P = 0.003) For pitchers, significant risk factors included longer experience of official baseball (OR = 1.342; 95% CI = 1.098-1.640; P = 0.004), lower total shoulder rotation angle (OR = 1.016; 95% CI = 1.004-1.027; P = 0.006), and lower total elbow arm angle (OR = 1.075; 95% CI = 1.024-1.129; P = 0.004) (Table 5). There were no significant risk factors for elbow structural abnormalities in fielders.

CONCLUSION

For Taiwan high school pitchers, longer official baseball experience, decreased shoulder total rotational angle, and decreased elbow total flexion/extension angle, were related to ultrasonographic structural abnormalities in elbows.

Early versus delayed mobilization for arthroscopic rotator cuff repair (small to large sized tear): a meta-analysis of randomized controlled trials

BACKGROUND

The timing to start passive or active range of motion (ROM) after arthroscopic rotator cuff repair remains unclear. This systematic review and meta-analysis evaluated early versus delayed passive and active ROM protocols following arthroscopic rotator cuff repair. The aim of this study is to systematically review the literature on the outcomes of early active/passive versus delayed active/passive postoperative arthroscopic rotator cuff repair rehabilitation protocols.

METHODS

A systematic review and meta-analysis of randomized controlled trials (RCTs) published up to April 2022 comparing early motion (EM) versus delayed motion (DM) rehabilitation protocols after arthroscopic rotator cuff repair for partial and full-thickness tear was conducted. The primary outcome was range of motion (anterior flexion, external rotation, internal rotation, abduction) and the secondary outcomes were Constant-Murley score (CMS), Simple Shoulder Test Score (SST score) and Visual Analogue Scale (VAS).

RESULTS

Thirteen RCTs with 1,082 patients were included in this study (7 RCTs for early passive motion (EPM) vs. delayed passive motion (DPM) and 7 RCTs for early active motion (EAM) vs. delayed active motion (DAM). Anterior flexion (1.40, 95% confidence interval (CI), 0.55-2.25) and abduction (2.73, 95%CI, 0.74-4.71) were higher in the EPM group compared to DPM. Similarly, EAM showed superiority in anterior flexion (1.57, 95%CI, 0.62-2.52) and external rotation (1.59, 95%CI, 0.36-2.82), compared to DAM. There was no difference between EPM and DPM for external rotation, retear rate, CMS and SST scores. There was no difference between EAM and DAM for retear rate, abduction, CMS and VAS.

CONCLUSION

EAM and EPM were both associated with superior ROM compared to the DAM and DPM protocols. EAM and EPM were both safe and beneficial to improve ROM after arthroscopic surgery for the patients with small to large sized tears.

Arthroscopic Lower Trapezius Tendon Transfer for a Patient with Axillary Nerve Injury and Concomitant Rotator Cuff Tear: A Case Report and Technical Notes

Introduction: Concomitant nerve injuries with musculoskeletal injuries present a challenging problem. The goals of nerve reconstruction for the shoulder include shoulder abduction and external rotation. When patients fail to achieve acceptable shoulder external rotation and shoulder abduction, tendon transfers such as trapezius transfer offer a reliable option in the subsequent stage. Case Presentation: A 32-year-old male presented with weak external rotation in his left shoulder, after previous axillary nerve reconstruction. He received the ipsilateral lower trapezius transfer with the aim of improving the external rotation. Discussion: The lower trapezius restores a better joint reaction force in both the compressive-distractive and anterior-posterior balancing and provides a centering force through the restoration of the anterior-posterior force couple. Conclusion: We believe that the ipsilateral lower trapezius transfer to the infraspinatus is a good outcome and is effective in improving overall shoulder stability and the shoulder external rotation moment arm or at least maintaining in neutral position with the arm fully adducted in patients with post axillary nerve injuries post unsatisfactory nerve reconstruction to increase the quality of life and activities of daily living.

Total intravenous anesthesia for geriatric hip fracture with severe systemic disease

PURPOSE

Our study aimed to determine the impact of a novel technique of anesthesia administration on the clinical outcomes and complications in geriatric patients with severe systemic disease undergoing hip surgery.

METHODS

We retrospectively identified patients aged > 65 years with severe systemic disease that was a constant of life [American Society of Anesthesiologists (ASA) IV] who underwent surgery for hip fracture between January 2018 and January 2020. The patients were divided into two groups: Group I [fascia iliaca compartment block plus propofol-based total intravenous anesthesia (FICB + TIVA)] and Group II [general anesthesia (GA)]. The primary outcomes were 30-day and 1-year mortality. The secondary outcomes included length of hospital stay, length of intensive care unit (ICU) stay, postoperative morbidity, Visual Analog Scale score, and consumption of analgesics.

RESULTS

There was no significant difference in the 30-day mortality (5 vs. 3.8%, p = 0.85) and 1-year mortality (15 vs. 12%, p = 0.73) between the groups. Group I had significantly lower ICU requirements (p = 0.01) and shorter lengths of ICU stay (p < 0.001) and hospital stay (p < 0.001). Moreover, a smaller proportion of patients in Group I required postoperative morphine or oral opiates.

CONCLUSION

Geriatric patients who underwent hip surgery under FICB + TIVA required fewer ICU admissions, shorter lengths of ICU and hospital stay, and had lesser postoperative opioid consumption than those who were under GA. Hence, we recommend the novel FICB + TIVA technique for hip fracture surgery in geriatric patients with poor general health status and high surgical risks (ASA IV).

Comparative Analysis of Posterior Approach Versus Anterior Approach for Posterior Tibial Plateau Fractures: A Systematic Review and Meta-analysis

BACKGROUND

Posterior tibial plateau fractures can lead to significant posttraumatic instability if not treated properly. It remains unclear which surgical approach achieves better patient outcomes. The objective of this systematic review and meta-analysis was to assess postoperative outcomes in patients undergoing anterior, posterior, or combined approach for posterior tibial plateau fractures.

METHODS

The PubMed, Embase, Web of Science, The Cochrane Library, and Scopus were searched for studies published before October 26, 2022, comparing anterior, posterior, or combined approaches for posterior tibial plateau fractures. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Outcomes included complications, infections, range of motion (ROM), operation time, union rates, and functional scores. Significance was set at p < 0.05. Meta-analysis was conducted with STATA software.

RESULTS

In total, 29 studies with a total of 747 patients were included for quantitative and qualitative analysis. Compared with other approaches, the posterior approach for posterior tibial plateau fractures was associated with a better ROM and shorter operative time. The complication rates, infection rates, union time, and hospital for special surgery (HSS) scores were not significantly different between surgical approaches.

CONCLUSIONS

The posterior approach for posterior tibial plateau fractures offers advantages such as improved ROM and shorter operative time. However, there are concerns regarding prone positioning in patients with medical or pulmonary comorbidities and indications in polytrauma cases. Further prospective studies are needed to determine the optimal approach for these fractures.

LEVEL OF EVIDENCE

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

Distraction Gap Needed for Safe Central Compartment Access in Hip Arthroscopy

BACKGROUND

Sufficient distraction of the hip is the key to a safe central compartment (CC) approach in hip arthroscopy. However, an adequate distraction gap has not been scientifically identified.

PURPOSE

To determine the sufficient amount of distraction that could predict a successful CC access as well as to identify the risk factors for a failed or difficult CC access.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

All patients who underwent hip arthroscopy by a single surgeon between January 2018 and April 2019 were prospectively enrolled. We analyzed gaps of the hip on 4 C-arm fluoroscopic images: nondistraction, preoperative manual traction, preoperative maximal traction (without distension), and intraoperative maximal traction (at the end of CC procedures in a successful CC approach or after peripheral compartment procedures in a failed or difficult CC approach). A failed CC approach was defined as failure in introducing the anterolateral portal to the CC under arthroscopic control; a difficult CC approach was defined as the presence of an incomplete diagnostic round in the CC because of a small distraction. The amount of distraction was evaluated by the ratio of the distracted gap to the undistracted gap. Patients were classified into the successful CC access group (group 1) and the failed/difficult CC access group (group 2). The amount of distraction, demographic characteristics, and preoperative radiographic parameters were compared between the groups.

RESULTS

A total of 240 patients were included in this study. Group 1 consisted of 205 patients (113 males and 92 females; mean ± SD age, 34.5 ± 11.4 years), and group 2 consisted of 35 patients (27 males and 8 females; age, 32.5 ± 11.2 years). The preoperative joint space width was not significantly different between group 1 (mean ± SD, 3.89 ± 0.83 mm) and group 2 (3.68 ± 0.68 mm). The ratio of the amount of distraction at lateral gaps under all traction conditions was significantly greater in group 1 compared with group 2 (1.50 ± 0.54 vs 1.26 ± 0.35, respectively, under preoperative manual traction; 2.84 ± 0.76 vs 2.03 ± 0.63 under preoperative maximal traction; 3.36 ± 0.96 vs 2.50 ± 0.79 under intraoperative maximal traction). An increase of the lateral gap by >2.2 times (P < .001) under preoperative maximal traction and by >2.7 times (P < .001) under intraoperative maximal traction could predict successful CC access. Male sex (odds ratio [OR], 2.94; P = .017) and increased lateral center-edge angle (OR, 1.08 for every 1° increase; P = .004) were significant risk factors for failed/difficult CC access.

CONCLUSIONS

An increase of the lateral gap by >2.2 times during an unsterile traction test without joint distension could predict successful CC access. Male sex and increased lateral center-edge angle were risk factors for a failed or difficult CC access.

Combined 3-Dimensional CT and Multidirectional CT Arthrography for Femoroacetabular Impingement and Hip Lesions: A Cross-sectional Study Comparing Imaging and Hip Arthroscopic Surgery Findings

Background

There is limited research investigating the diagnostic strength of 3-dimensional computed tomography (3D-CT) and multidirectional CT arthrography (CTA) for femoroacetabular impingement (FAI) and related hip lesions.

Purpose

To evaluate the diagnostic strength of combined 3D-CT and CTA in patients with FAI and related hip lesions by comparing it with hip arthroscopic surgery findings.

Study Design

Cohort study (diagnosis); Level of evidence, 2.

Methods

This study included patients who were suspected of having FAI and related hip lesions and who underwent a combination of 3D-CT and CTA and subsequent hip arthroscopic surgery between December 2013 and December 2017. The CT and intraoperative arthroscopic findings were recorded and compared. The sensitivity, specificity, and accuracy of 3D-CT for FAI and those of CTA for related hip lesions were calculated.

Results

A total of 114 patients with 114 hips were included in our study. There were 101 patients with positive findings and 13 patients with negative findings for FAI (including cam, pincer, and combined morphology) according to 3D-CT. The sensitivity, specificity, and accuracy of 3D-CT for FAI were 91.58%, 57.14%, and 89.47%, respectively. The sensitivity, specificity, and accuracy of CTA for labral tears were 94.64%, 100.00%, and 94.73%, respectively. For acetabular cartilage defects, the sensitivity, specificity, and accuracy of CTA were 60.71%, 91.37%, and 76.31%, respectively. For femoral cartilage defects, the sensitivity, specificity, and accuracy of CTA were 82.22%, 76.81%, and 78.94%, respectively.

Conclusion

The study results indicated that 3D-CT was able to provide excellent accuracy for FAI compared with hip arthroscopic surgery findings. In addition, multidirectional CTA demonstrated promising diagnostic strength for hip lesions such as labral tears and chondral defects.

The posterior capsule is distended in dysplastic hips, but the anterior capsule is not

PURPOSE

In the setting of acetabular dysplasia, the increased translational motion of the femur may damage the labrum and cartilage, as well as stretch the capsule. The purpose of the study was to investigate the relationship between the acetabular coverage and the capsular stiffness by assessing the distension of anterior and posterior joint recesses on the hip computed tomography arthrography.

METHODS

One hundred thirty-three patients (138 hips) with a median age of 36 years (range 18-50 years) who received the computed tomography arthrography for evaluation of nonarthritic hip pain in our institute between 2015 and 2017 were retrospectively reviewed. The maximal distance between the anterior/posterior capsule and the anterior femoral head-neck junction/posterior femoral head on the axial imaging of computed tomography arthrography was defined as the width of anterior/posterior joint recess. The width of anterior/posterior joint recess was adjusted with the diameter of the femoral head and was then compared between acetabular dysplasia (lateral center-edge angle < 25°), normal acetabulum (lateral center-edge angle between 25 and 39°), and deep acetabulum (lateral center-edge angle > 39°). In addition, the standard univariate linear regression analysis was used to investigate the relationship between the adjusted width of anterior/posterior joint recess and anterior/posterior coverage of the hip, determined by the anterior/posterior wall index.

RESULTS

The adjusted width of posterior joint recess was significantly greater in the acetabular dysplasia group than the normal acetabulum and deep acetabulum groups (p < 0.01 and p = 0.02, respectively). There was no significant difference of the adjusted width of anterior joint recess between the groups (n.s.). The adjusted width of posterior joint recess had a significant but weak negative correlation with the anterior wall index (r =  - 0.25, p < 0.001), and no correlation with the posterior wall index (r =  - 0.0004, n.s.). There was no significant correlation between the adjusted width of anterior joint recess and the anterior/posterior wall index (r = 0.05, n.s./r = 0.07, n.s.).

CONCLUSIONS

The distension of posterior capsule on the computed tomography arthrography was significantly greater in acetabular dysplasia. In addition, there was a significant but weak negative correlation between the distension of posterior capsule and the anterior coverage of the hip. It indicated a looser posterior capsule was observed in a dysplastic hip. The relevance of posterior capsular laxity to clinical outcomes warrants further investigation. Given the fact that the distension of anterior capsule was not significantly higher in acetabular dysplasia, the need of anterior capsular plication in a dysplastic hip should be carefully evaluated.

LEVEL OF EVIDENCE

Level III.

Comparison of Hook Plate Alone, Hook Plate Augmented with Suture Anchor, and Arthroscopically-assisted TightRope Fixation in the Treatment of Patients with Acute Type V Acromioclavicular Joint Dislocations

INTRODUCTION

The best treatment for Rockwood type V acromioclavicular (AC) joint dislocation is unknown.

HYPOTHESIS

Hook plate augmented with suture anchor (HA) may have different clinical and radiological results than hook plate alone (H), and arthroscopically assisted TightRope (TR) techniques in treating acute type V AC joint dislocations.

MATERIAL AND METHODS

This retrospective study included 71 patients with acute type V AC joint dislocations between December 2010 and August 2018. Patients were categorized into three groups: H group (n =22), HA group (n =23) and TR group (n =26). We measured the coracoclavicular distance (CCD) differences and CCD ratio compared to uninjured side pre-operatively, immediately post-operatively, at 3-month and 2-year after operation. Clinical outcomes were assessed as well at the same time points. Loss of correction was determined by the CCD difference and ratio between surgical and uninjured sides.

RESULTS

The mean age and follow-up period were 41.8±24.7 years and 30.2±4.3 months, respectively. No significant differences were found in the demographic data between the three groups. The HA group presented a trend of less overcorrection but without significance compared with the H group at immediately post-operation, 3-month, and 2-year follow-up. (CCD difference: -2.4mm vs. -3.7mm, -1.6mm vs. -1.8, and 0.2mm vs -1.9mm, CCD ratio: 67.7% vs. 40.9%, 79.3% vs. 70.1%, and 100.6% vs. 86.5%, respectively). The HA group also had significantly less loss of correction compared with the TR group at 3-month and 2-year after the operation (CCD difference: -1.6mm vs. 1.6mm, 0.2mm vs. 2.4mm; CCD ratio: 79.3% vs. 122.2%, 100.6% vs. 136.1%, all p<0.05). All three methods achieved significant improvement in function and pain without inter-group differences. No coracoid-related or tunnel complications occurred.

DISCUSSION

The hook plate alone, and hook plate with suture anchor augmentation techniques provided less residual vertical instability compared to TightRope fixation at 2-year follow-up. The patient-reported functional outcomes were promising and comparable among the three groups.

LEVEL OF EVIDENCE

III, Retrospective comparative therapeutic trial.

Outcomes of arthroscopic management for pigmented villonodular synovitis of the hip

INTRODUCTION

Early synovectomy is considered as the main treatment of pigmented villonodular synovitis (PVNS) of the hip in young patients with preserved cartilage. The purpose of the study is to evaluate outcomes of arthroscopic management for PVNS of the hip.

METHODS

Patients who underwent primary hip arthroscopy for the treatment of histology-confirmed PVNS by the senior author between January 2012 and December 2016 were retrospectively reviewed. We excluded patients who had less than 1-year follow-up or had undergone primary surgeries with other surgeons and then received revision hip arthroscopic procedures by the senior author. The recurrence of PVNS and postoperative condition of affected hip were assessed by follow-up magnetic resonance imaging (MRI). Patient-reported outcomes of modified Harris hip score (mHHS) and 12-item International Hip Outcome Tool (iHOT-12) were collected at latest follow-up.

RESULTS

Nine patients (2 males, 7 females) with a mean age of 24.3 ± 11.2 years (range 14-44 years) were included in this study. Localized PVNS was observed in four patients, and diffuse PVNS was observed in five patients. No patient presented with advanced osteochondral destruction. Five patients received single adjuvant radiosynoviorthesis. No patient had evidence of recurrence based on follow-up MRI. Patient-reported outcomes were obtained in eight patients at mean 55.8 ± 26.1 months (range 24-84 months) after the index surgery. The mean mHHS was 94.6 ± 4.9 (range 84.7-100) and the mean iHOT-12 was 93.3 ± 20.2 (range 50-120). No patient needed secondary surgery during the follow-up period.

CONCLUSION

Arthroscopic subtotal synovectomy can offer favorable short to mid-term outcomes in the treatment of hip PVNS in case of no advanced osteochondral damage at presentation.

Arthroscopic-Assisted Lower Trapezius Tendon Transfer With Autologous Semitendinosus Tendon and Long Head of Biceps Superior Capsule Reconstruction for Massive Irreparable Posterosuperior Rotator Cuff Tears

We present a surgical technique combining arthroscopic-assisted lower trapezius tendon (LTT) transfer with autologous semitendinosus tendon and long head of biceps tendon (LHBT) superior capsule reconstruction (SCR) for massive irreparable posterosuperior rotator cuff tears. The patients are placed in the beach-chair position with the ipsilateral lower leg prepared simultaneously. After both tendons are harvested, 1 limb of a semitendinosus graft is fixed with the LTT via a Krakow suture. The LHBT is then fixed by an anchor 5 to 8 mm posterior to the bicipital groove and tenotomized distally. The transverse humeral ligament is released afterward to provide better visualization. A Beath pin is introduced from anterolateral portal, aiming at the bicipital groove, and drilled posteriorly until it exits at the infraspinatus footprint. Next, 4.5- and 8-mm cannulated drills are used sequentially to create a humeral tunnel. A shuttle suture passed through infraspinatus fascia in the back brings the EndoButton and looped semitendinosus graft from posterior to anterior of the humerus, until the EndoButton flips and is fixed inside the bicipital groove. The shoulder is placed in 45° abduction and 30° external rotation. The free limb of semitendinosus tendon is then sutured with LTT with the desired tension.

Preoperative Alpha Angles Can Predict Severity of Acetabular Rim Chondral Damage in Symptomatic Cam-Type Femoroacetabular Impingement: A Prospective Observatory Study

PURPOSE

To identify the relationship between the alpha angle and the severity of chondrolabral separation as well as acetabular rim chondral damage in symptomatic cam-type femoroacetabular impingement (FAI) with or without focal pincer-type FAI.

METHODS

Patients who received hip arthroscopy under the diagnosis of symptomatic cam-type FAI between January 2018 and August 2018 were identified in a prospectively collected database. Patients were excluded if preoperative lateral center-edge angle <25°, lateral center-edge angle ≥40°, Tönnis grade >1, with previous surgery on the affected hip, or with concomitant synovial disease. The chondrolabral junction was classified into intact chondrolabral junction, stable chondrolabral separation and unstable chondrolabral separation. The classification of acetabular rim chondral damage was modified from the MAHORN (Multicenter Arthroscopy of the Hip Outcomes Research Network) classification: normal/softening, bubble, pocket, flap, and exposed bone. The relationship between the hip morphology and severity of chondrolabral junction and acetabular rim chondral damage was assessed.

RESULTS

A total of 71 patients with the mean age of 33.2 ± 11.0 years were included. Preoperative alpha angles on anteroposterior (AP) or Lauenstein view positively correlated with the severity of acetabular rim chondral damage (P = .028 and P = .016, respectively). A significant increment of the alpha angle between 2 consecutive grades of acetabular rim chondral damage was 7.1° (P = .001) on AP view and 5.2° on Lauenstein view (P = .001). The cut-off values for predicting advanced acetabular rim chondral damage (pocket, flap or bony exposure) were an AP alpha angle of 70° (P = .025) and a Lauenstein alpha angle of 57° (P = .003). There was no significant association between the alpha angle and the severity of chondrolabral separation.

CONCLUSIONS

In patients with symptomatic cam-type FAI with or without focal pincer-type FAI, greater preoperative alpha angles on AP and Lauenstein views can predict more severe acetabular chondral damage.

LEVEL OF EVIDENCE

Level III.

The clinical outcomes of arthroscopic hip labral repair: a comparison between athletes and non-athletes

The objective of this study is to compare the clinical outcomes after arthroscopic hip labral repair in athletes and non-athletes. The design of this study is a retrospective comparative study. The setting of this study is an institutional study. One hundred and sixteen patients of hip labral tears who underwent arthroscopic labral repair were included. Eighty-five of these patients met the inclusion/exclusion criteria (25 athletes and 60 non-athletes). Hip labral tears underwent arthroscopic labral repair. The main outcome measures are as follows: visual analog scale (VAS) and modified Harris Hip Score (mHHS) 2 years postoperatively and the rate of return to sports at previous level. There was no significant difference in the gender, alpha angle, lateral center-edge angle between the two groups, except for the mean age (19.3 versus 42.2, P &lt; 0.001), Marx activity rating scale (MARS) (14.6 versus 6.8, P &lt; 0.001) and University of California, Los Angeles (UCLA) activity rating scale (9.6 versus 5.0, P &lt; 0.001). The intraoperative findings were similar in the two groups. The VAS scores and mHHS both showed a significant improvement after surgery in both groups (VAS improvement 3.6 and mHHS improvement 22.4 in the athlete group; VAS improvement 3.9 and mHHS improvement 25.0 in the non-athlete group, all P &lt; 0.001). There was no difference in VAS improvement or mHHS improvement between the athlete and non-athlete groups. All the patients in the athlete group return to sports at previous level 6 months after the operation. The mean time of return to sports at previous level was 5.4 months. Both athletes and non-athletes demonstrate significant VAS and mHHS improvement following arthroscopic labral repair. The VAS scores improvement and mHHS improvement were similar in the athlete and non-athlete groups after arthroscopic labral repair.

A COVID-19 screening method based on eyes photographs and artificial intelligence

Background

SARS-CoV-2 can spread both from symptomatic and asymptomatic individuals. Ocular manifestations due to SARS-CoV-2 have been described, being conjunctival inflammation the most common affectation. Evidence shows that conjunctivitis could be the first and/or only manifestation of COVID-19. This study aimed to develop and validate a COVID-19 screening method based on eyes photographs and artificial intelligence.

Methods

In this multicentre study, 1,200 participants were enrolled from Shanghai Public Health Clinical Center (SPHCC) Fudan University, AIMOMICS LAB and La Fe University and Polytechnic Hospital (LFUPH) of Valencia (Spain). Pictures of participants' ocular surface were taken in four different positions with mobile phone cameras, and a Deep Learning System (DLS) was developed through machine learning to identify characteristic conjunctival inflammation patterns. The study was conducted in accordance with the Declaration of Helsinki and was approved by the Ethics Committees of SPHCC and LFUPH.

Results

The area under the receiver-operating-characteristic curve (AUC), sensitivity, specificity, and accuracy were calculated according to the results of our binary classification network. Bootstrapping with 1,000 replicates was used to estimate 95% confidence intervals of the performance metrics, with photography as the resampling unit. On the subject-level classification, the network achieved the AUC of 0.976 (95% CI 0.965-0.988) among Asian population and 0.892 (95% CI 0-763-1.000) among Caucasian population.

Conclusions

Preliminary results show that this DLS performed well in identifying probable asymptomatic COVID-19 cases through the analysis of participants' eyes pictures. This method could be an innocuous, accessible, low cost and quick COVID-19 screening method. Eventually, it could potentially contribute to pandemic control.

Key messages

In the context of the COVID-19 pandemic it would be useful to have a screening method to easily and quickly detect asymptomatic individuals, in addition to using temperature control. Preliminary results show that this Deep Learning System (DLS) based on eyes pictures taken with mobile phone cameras could be an innocuous, accessible, low cost and quick COVID-19 screening method.

Anatomical Dermal Allograft and Autologous Biceps Long Head Superior Capsule Reconstruction for Irreparable Posterosuperior Rotator Cuff Tears

Superior capsule reconstruction (SCR) can be performed using fascia lata, dermal allograft, and long head of the biceps tendon (LHBT). We present a Technical Note combining dermal allograft and autologous LHBT, reconstructing the superior capsule's actual anatomical thickness and augmenting with single-stranded LHBT. The glenoid side consists of intact LHBT insertion and is covered with dermal allograft. The lateral side comprises posteriorly transpositioned LHBT, dermal allograft, and repairable remnant cuff. First, 1 suture-based anchor is used to fix the biceps 5 to 8 mm posterior to the bicipital groove, and tenotomy is done distal to it, while the glenoid side of the biceps is preserved. Second, 2 suture-based anchors are used to fix the dermal allograft at the glenoid side by 1 double-pulley and 2 mattress sutures. Third, 2 SwiveLock anchors are used to fix allograft's lateral side by 2 reverse mattress sutures. The tension and coverage of the graft can be determined by the position of the SwiveLock anchors. In this way, fewer anchors are needed than the conventional dermal allograft SCR and larger footprint coverage can be achieved than LHBT SCR. A better spacer effect may be achieved by combining both biological grafts' thickness, mimicking the intact shoulder's true anatomy.

Mid- to long-term clinical outcomes of arthroscopic surgery for external snapping hip syndrome

This study evaluated the outcomes of arthroscopic surgery for the treatment of external snapping hip at 2- to 10-year follow-ups. Eighteen patients with refractory external snapping hip treated by arthroscopic surgery were enrolled in this prospective study. All patients underwent unsuccessful conservative treatment for more than 3 months before surgery. We made diamond-shaped defects on the iliotibial band and resected peripheral fibrosis tissues for iliotibial band release with an arthroscopic approach. The visual analog scale (VAS), modified Harris hip score and return to previous level of activity were evaluated as functional outcomes. In addition, residual discomfort or the presentation of complications was also investigated. The average follow up period was 7 years. The modified Harris hip score increased from 70.08 preoperatively to 93.14 postoperatively, and the VAS score decreased from 3.67 preoperatively to 1.17 2 weeks after the operation and declined to 0.33 at the last follow-up. Neither recurrence of snaps nor complications were recorded. Two patients complained of a tight sensation with tenderness after exertion. Our clinical outcomes were compatible with those of previous studies, and no long-term complications were noted, even with a relatively longer follow-up period than what was reported in previous studies. Arthroscopic surgery is a safe and effective treatment that can provide promising long-term clinical outcomes for patients with refractory external snapping hip.

Hip arthroscopy via a peripheral compartment first capsular-preserving technique: a step-by-step description

Hip arthroscopy is a well-recognized procedure for the treatment of several hip pathologies. Different methods of arthroscopic access to the hip have been published. The most popular approach is the central compartment first technique, where the first portal to the central compartment is placed under traction and fluoroscopic control. This technique, however, carries the risk of iatrogenic damage to the cartilage and labrum, especially when adequate distraction cannot be obtained. In addition, secondary exposure of the peripheral compartment frequently requires larger capsulotomies. The current article is to describe an alternative arthroscopic approach to the hip with the peripheral compartment being first accessed. The peripheral compartment first technique offers the advantages of a limited capsular release for peripheral compartment exposure and a reduced risk of iatrogenic cartilage and labrum damage during subsequent central compartment portal placement.

Prognostic factors and outcomes of secondary surgery after plate fixation for midshaft clavicle fracture: Comparison of traditional DCP and pre-contoured locking plate

OBJECTIVES

This study aimed to evaluate the prognostic factors of reoperation after plate fixation for midshaft clavicle fracture and compare outcomes of dynamic compression plates (DCP) and pre-contoured locking plates.

DESIGN

Retrospective comparative study.

SETTING

Level I trauma center.

PATIENTS/PARTICIPANTS

We recruited 274 consecutive patients who underwent plate fixation for midshaft clavicle fracture from 2007 to 2017 and completed at least 1 year of follow-up.

INTERVENTION

235 patients underwent surgery with DCP, while 39 patients were treated with locking plate.

MAIN OUTCOME MEASUREMENTS

We reviewed the possible variables of secondary surgeries, and documented complications from the medical records. Patients with a DCP or locking plate were further divided for outcome comparisons.

RESULTS

150 (54.7%) patients underwent reoperation after the initial surgery, and plate removal represented the major etiology. On multivariate analysis, superficial wound infection and prominent implant were identified as significant risk factors for reoperation, while aging, locking plate usage, and higher body mass index (BMI) were protective factors (all P < 0.05). The locking plate featured a significantly decreased implant removal rate (7.7% vs. 60.9%, P < 0.05).

CONCLUSIONS

Patients with risk factors for superficial wound infection or a prominent implant tended to require a secondary operation after surgery for midshaft clavicle fracture, while aging, pre-contoured locking plate usage, and higher BMI decreased the risk. Compared with DCP, patients with locking plates tended to have better prognosis and significantly lower implant removal rates.

LEVEL OF EVIDENCE

Prognostic III.

[Key points and skills of assistant in robotic radical gastrectomy for gastric cancer]

An excellent assistant for robotic radical gastrectomy can play an important role in the operation, especially in a initial team. In robotic gastric cancer surgery, an excellent assistant should actively participate in the operation process, choose the appropriate trocar position according to patient's body habitus. Moreover, he should master various surgical instruments skillfully and switch instruments fluently to assist the surgeon to expose key parts during operation, and provide effective help in the operative details, so that the whole operation process can run more smoothly and the operation efficiency and quality will be greatly improved. The growth of the assistants needs constant practice and summary of experience. Meanwhile, the encouragement of the chief surgeon also plays a positive role in promoting the development of the assistants.

Surgical Outcomes in the Treatment of Concomitant Mild Acetabular Dysplasia and Femoroacetabular Impingement: A Systematic Review

PURPOSE

To analyze the current approaches and clinical outcomes in the surgical management of concomitant mild acetabular dysplasia and femoroacetabular impingement (FAI).

METHODS

Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) method, the PubMed and Medline databases were searched in March 2019 for studies that reported on surgical outcomes in hips with concomitant mid acetabular dysplasia and FAI. Studies published in English that focused on the surgical outcomes after hip arthroscopy, open surgery, or periacetabular osteotomy of concomitant acetabular dysplasia and FAI, in which the lateral center-edge angle of all subjects was between 15° and 25°, were included. Articles that included subjects with lateral center-edge angle <15°, with a minimum follow-up duration <1 year, had <5 subjects, or were not original articles were excluded.

RESULTS

The initial search yielded 748 studies, and 5 studies met the inclusion criteria. All these 5 studies focused on hip arthroscopic treatment for patients with concomitant mild acetabular dysplasia and FAI. Three studies had level III evidence, whereas 2 studies had level IV evidence. The mean patient age range across the studies was 29.8 to 49.6 years, and the female-to-male ratio was 1.14. Improved patient-reported outcomes (Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sport, modified Harris Hip Score, Short Form-12 Physical Component Summary, Western Ontario and McMaster Universities Osteoarthritis Index) at a minimum 2-year follow-up were obtained in 4 of the 5 studies. Two of these 4 studies had a comparative cohort of patients with FAI with normal acetabular coverage, and there was no significant difference in the postoperative outcomes and secondary procedure rate between patients with mild acetabular dysplasia and those with normal acetabular coverage.

CONCLUSIONS

This systematic review indicates that improved patient-reported outcomes can be obtained with hip arthroscopy in the treatment of concomitant mild acetabular dysplasia and FAI at a minimum 2-year follow-up.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III and Level IV studies.

P1499 A case of missing left ventricular apex

Introduction

Isolated left ventricle (LV) apical hypoplasia is a rare congenital anomaly. Echocardiographic diagnosis is challenging if one is not aware of this condition. It can masquerade as LV non-compaction or apical aneurysm. Multimodality imaging with cardiac magnetic resonance (CMR) can be useful to secure the diagnosis.

Case description

An asymptomatic 18-year-old man, with no significant personal or family medical history, was referred to cardiology clinic due to abnormal electrocardiogram (ECG) during routine cardiac screening. ECG showed right axis deviation and delayed precordial QRS-transition. He had excellent effort tolerance during treadmill exercise test (standard Bruce Protocol stage 6). Ambulatory ECG monitoring was within normal limits.

Transthoracic echocardiogram showed a truncated appearance of LV apex with increased apical trabeculation, and bulging right ventricle apex (see image A and B). LV ejection fraction was preserved. The LV appearance was initially thought to be due to foreshortened apical view. A diagnosis of LV non-compaction cardiomyopathy was also inaccurately considered.

He was further evaluated with CMR imaging. The study showed a truncated LV apex and apical insertion of the papillary muscles. RV apex was seen wrapping around the LV (see image C and D). Both the LV and RV function were normal. There was no late gadolinium enhancement (LGE). The morphological abnormalities were consistent with the diagnosis of isolated LV apical hypoplasia.

Patient continued to be physically active and asymptomatic. Follow up CMR five years later showed similar findings of preserved biventricular functions and no fibrosis on LGE imaging.

Discussion

We described a rare case of isolated LV apical hypoplasia with longitudinal clinical and cardiac imaging follow up. Initial diagnosis from transthoracic echocardiogram was elusive, and supportive findings from CMR helped to secure the diagnosis.

In the literature, the clinical presentation ranges from chest pain syndrome, arrhythmias, heart failure or as incidental finding during cardiac imaging, as in our case. It is commonly diagnosed as nonspecific cardiomyopathy when the clinician is not aware of this condition.

Being a rare congenital anomaly, the prognosis is not well established. Our patient remained asymptomatic clinically with preserved biventricular function in his 5 years follow-up.

Abstract P1499 Figure. Echo and CMR imaging

Long-term antibacterial performances of biodegradable polylactic acid materials with direct absorption of antibiotic agents

In this study, polylactic acid (PLA) disks with antibacterial performances were prepared using 3D printing technology combined with direct adsorption of the antibiotic agents in solution baths. The effects of the layer thicknesses for the building of the 3D printing PLA disks and the amounts of antibiotic agents absorbed onto the sample surfaces on their antibacterial activities were investigated. The antibiotic agent release profiles from the samples surface into the buffer solution show that the antibacterial performances of these samples can reach up to 28 days. With a decrease in the concentration of antibiotic agent in the solution bath, the amount of antibiotic agent adsorbed on the sample surfaces also decreases, but their antibacterial performances can still maintain at least 7 days. In the bioactivity tests of the various organisms, the release amount of antibiotic agent from the sample can inhibit E. coli and S. aureus for over 80% up to 28 days. In the antibacterial activity tests, a PLA disk with suitable antibiotic agents covering its surface has a good inhibitory effect on the growth ability of S. aureus of less than 50% in six hours.

In this study, we developed a surface modification of 3D printing PLA disks. The relative optical density of the S. aureus in the solution can reduce to 40% using the PLA disk directly absorbed with suitable antibiotic agents.

Correlation of parameters on preoperative CT images with intra-articular soft-tissue injuries in acute tibial plateau fractures: A review of 132 patients receiving ARIF

INTRODUCTION

Tibial plateau fractures often occur in conjunction with soft-tissue injuries of knees. The hypothesis of this study is that parameters of CT imaging can predict intra-articular soft-tissue injuries.

PATIENTS AND METHODS

Patients who underwent arthroscopically assisted reduction and internal fixation (ARIF) for acute tibial plateau fractures performed by a single orthopedic surgeon between 2005 and 2015 were included in this retrospective study. Patients with concomitant ipsilateral femoral fractures, who had received revision surgery or who had undergone index surgery more than 30days from the event were excluded. We measured lateral plateau depression and widening, medial plateau depression and displacement, and column involvement observed on preoperative CT scans. Intra-articular soft-tissue injuries were diagnosed based on findings from knee arthroscopy. The correlation of imaging parameters with soft-tissue injuries was analyzed by the area under a receiver operating characteristic (AUROC) curve and multivariate logistic regression.

RESULTS

One-hundred and thirty-two patients were enrolled in the study. The average age was 45.7±13.1 years (range: 18-75 years). Lateral tibial plateau depressions >11mm were significantly associated with increased risk of lateral meniscus tears (p=0.001). However, there was no significant threshold of lateral tibial plateau widening that could be used to predict lateral meniscus tear. Greater risk of anterior cruciate ligament (ACL) avulsion fracture was observed in younger patients, patients with high-energy-pattern tibial plateau fractures, patients with fractures involving anteromedial or posterolateral columns, and patients with medial tibial plateau displacement >3mm (p<0.05).

CONCLUSION

Measuring lateral tibial plateau depression and column involvement on preoperative CT scans can help predict a higher risk of lateral meniscus tear and ACL avulsion fracture respectively in patients with acute tibial plateau fractures.

A Review of Three Commonly Used Herbs Which Enhance Memory and New Evidences Which Show Their Combination Could Improve Memory in Young Animals

BACKGROUND

This review looks into the herbs Gingko biloba, Polygala tenuifolia, and Lycii fructus for their widely studied neuroprotective properties. In particular, we investigated memory enhancing effect of these herbs, and their potential synergetic effect on memory with new data. Sixmonth treated mice demonstrated shorter escape latency in water maze and shorter arrival time in a consolidated memory task. Immunochemistry showed evident increase in superoxide dismutase activities in the prefrontal cortex, implying protection against free radicals during aging. Discrete increase of catecholaminergic neurons was found in the prefrontal cortex, hippocampus, corpus striatum, and midbrain, suggesting better memory and better control on mood and behavior. Necrotic cells in the brain decreased as indicated by immunocytochemistry of lactic dehydrogenase. Terminal deoxynucleotidyl transferase dUTP nick end labeling showed no apoptotic cells in most brain areas in high dose group. Biochemistry revealed increase of dopaminergic cells in treatment groups at prefrontal cortex, and in the hippocampus and cerebellum of the high dose group. Most 6-month groups showed increase of serotonin in all three areas. For the high dose group, GABA increased in the hippocampus but not prefrontal cortex, which would help induce sleep at night. Protein kinase C increased in most groups at prefrontal cortex, hippocampus and cerebellum, signifying increase of possible signal transduction pathways for memory or other nervous activations.

CONCLUSION

Our results intimate that the interaction of the three herbs exerts beneficial effects on memory, associated cognitive function, and necrosis. Future investigations based on the present data shall aid development of clinically relevant medication.

Three months of methoxetamine administration is associated with significant bladder and renal toxicity in mice

CONTEXT.: Methoxetamine is a ketamine analogue that has recently emerged as a novel psychoactive substance. Chronic ketamine use is associated with significant bladder and renal toxicity. Methoxetamine has been marketed as "bladder friendly", but there is no data to be able to substantiate this claim.

OBJECTIVE

To characterise the patterns of bladder and renal toxicity associated with 3 months of methoxetamine administration in an animal model.

MATERIALS AND METHODS

Two-month-old Institute of Cancer Research mice were administered 30 mg/kg methoxetamine intraperitoneally (n = 5) or saline (n = 3 control) for 3 months. The animals were then sacrificed and histological examination, immuno-cytochemistry using polyclonal anti-CD4 antibodies and sirius-red staining for collagen were performed.

RESULTS

The kidneys of methoxetamine-treated animals showed inflammatory cell infiltration, tubular cell necrosis and glomerular damage (1.9 ± 0.3% shrunken glomeruli in control, 9.8 ± 0.8% in methoxetamine-treated mice (p < 0.0001); 2.9 ± 0.3% tubular cell degeneration in control, 20.4 ± 1.1% in methoxetamine-treated mice (p < 0.0001)). There was a greater density of mononuclear cells in the bladder lamina propria and submucosa in methoxetamine-treated mice (43.0 ± 2.1 per 250 × 250 μm) than controls (7.1 ± 1.2 per 250 × 250 μm), p < 0.001. CD4-positive staining was seen in the bladder submucosa and lamina propria of all methoxetamine-treated mice and muscle-layer of two methoxetamine-treated mice; these changes were not seen in the control mice. There was an increase in sirius-red collagen in the bladder sub-mucosa and muscle-layer in the methoxetamine-treated mice compared with control mice.

DISCUSSION

This study has shown that 3 months of daily 30 mg/kg intra-peritoneal methoxetamine results in significant bladder and renal toxicity in mice. Changes in the bladder included inflammatory changes with subsequent fibrosis and changes in the kidney were seen at both a tubular and glomerular level. These changes are similar to those seen in comparable animal models of chronic ketamine administration. Further work is required to determine the time course of the onset of these effects and whether the effects are reversible with methoxetamine cessation.

Long term ketamine and ketamine plus alcohol toxicity - what can we learn from animal models?

This review addressed the adverse effects of the frequently-used recreational drug, ketamine through using mice and monkey models. Our laboratory has documented initially that ketamine can induce the formation of hyperphosphorlated tau (hypertau), which is a hallmark of Alzheimer's disease (AD), in the cerebral cortex of both mice and monkeys as well as apoptosis in neurons in these species. Besides the cerebral cortex, other centers in the central nervous system (CNS) and peripheral nervous system (PNS) are also influenced by ketamine. Cerebellum was found to be down-regulated in both mice and humans after long-term of ketamine administration and it was caused by the apoptosis of Purkinje cells. Deleterious effects in other organs reported in long-term ketamine users include of kidney dysfunction leading to proteinuria, fibrosis of the urinary bladder and reduction in size of the urinary bladder leading to frequent urination, increase of liver fibrosis and cardiac problems such as premature ventricular beats. Moreover, ketamine is usually co-administrated with other chemicals such as caffeine or alcohol. It has been reported increased harmful effects when ketamine was used in combination with the above substances. Mechanisms of damages of ketamine might be due to 1) up-regulation of NMDA receptors leading to overestimation of glutamatergic system or 2) the metabolite of ketamine which was a hydroquinone exerted toxicity.

Intestinal and liver changes after chronic ketamine and ketamine plus alcohol treatment

The effects of long-term chronic ketamine treatment on the intestine and the liver were studied in the ICR mice which had daily intraperitoneal injection of ketamine at 30 mg/kg per day for 7 months. The intestine showed no significant pathology after treatment but had a decrease of the positive sites of proliferative cell nuclear antigen in the mucosae of the intestines after ketamine and ketamine plus alcohol (added in the last month) treatment. No significant apoptosis (via TUNEL) nor necrosis (via lactic acid dehydrogenase) was detected in the intestines of all control and ketamine-treated groups, with the exception of an increase of lactic acid dehydrogenase in the mucosae of the intestines of the ketamine plus alcohol group. In the liver, loss of glycogen was observed in animals after ketamine and ketamine plus alcohol treatment, in addition to the pathology reported in a previous work. The decrease in quantity of glycogen in the liver reflected either a failure of glycogen synthesis from glucose or an increase of glycogenolysis in the liver.

Permanent deficits in brain functions caused by long-term ketamine treatment in mice

Ketamine, an injectable anesthetic, is also a popular recreational drug used by young adults worldwide. Ketamine is a non-competitive antagonist of N-methyl-d-aspartate receptor, which plays important roles in synaptic plasticity and neuronal learning. Most previous studies have examined the immediate and short-term effects of ketamine, which include learning and cognitive deficits plus impairment of working memory, whereas little is known about the long-term effects of repeated ketamine injections of common or usual recreational doses. Therefore, we aimed to evaluate the deficits in brain functions with behavioral tests, including wire hang, hot plate and water maze tests, plus examine prefrontal cortex apoptotic markers, including Bax, Bcl-2 and caspase-3, in mice treated with 6 months of daily ketamine administration. In our study, following 6 months of ketamine injection, mice showed significant deterioration in neuromuscular strength and nociception 4 hours post-dose, but learning and working memory were not affected nor was there significant apoptosis in the prefrontal cortex. Our research revealed the important clinical finding that long-term ketamine abuse with usual recreational doses can detrimentally affect neuromuscular strength and nociception as part of measurable, stable and persistent deficits in brain function.

Clinical features and outcome of emergency percutaneous intervention of left main coronary artery occlusion in acute myocardial infarction

INTRODUCTION

Acute myocardial infarction (AMI) due to left main coronary artery (LMCA) occlusion carries a grave prognosis. Large series reporting on the outcome of emergency revascularisation (percutaneous or surgical) of acute LMCA occlusion have been scarce. We seek to identify, in our local population, the clinical presentation and outcome of this group of patients.

METHODS

From January 2000 to December 2005, a total of 1,539 patients underwent primary percutaneous coronary angioplasty for AMI in our institution. 11 patients (0.8 percent) underwent percutaneous intervention to the LMCA. These patients became the subjects of our study. Data on demography, clinical features and outcome was collected from all in-hospital and clinical notes. One sub-investigator, who was blinded to the study outcome, assessed the angiographical features.

RESULTS

The overall inpatient mortality was 82 percent (9 out of 11). Nine out of 11 patients presented with cardiogenic shock. All patients presented with shock died during the hospital stay. All patients required intra-aortic balloon counter pulsation insertion. Of the two patients who survived till discharge, one had angioplasty followed by bypass surgery. The remaining one had angioplasty and stenting to the left main artery. Both survivors have been doing well without further major adverse cardiac event after an average of 64 months of follow-up.

CONCLUSION

Percutaneous revascularisation of acute LMCA occlusion is feasible and the best outcome is seen in stable patients. Prognosis is still poor in patients with unfavourable clinical features.

Electrocardiographical case. Beware of this ECG in patients presenting with cardiogenic shock

A 64-year-old Chinese man presented to the Accident and Emergency Department with chest pain and was found to be in cardiogenic shock. The electrocardiogram (ECG) showed features of acute myocardial infarction due to left main coronary artery occlusion,which had no ST elevation in precordial leads. Emergency coronary angiogram revealed left main coronary artery complete occlusion. Percutaneous intervention of the left main coronary artery was carried out. The epidemiology and clinical features of a left main occlusion were briefly described, and ECG features of a left main occlusion were discussed.

Organization of human cardiovascular-expressed genes on chromosomes 21 and 22

The recent availability of the sequenced and annotated DNA sequences of chromosomes 21 and 22 has initiated the next phase in the human genome project: the application of this resource. One facet of these data is that they provide a list of ordered genes along the chromosome that can be capitalized upon to determine gene position effects. Specifically, the physical position and distribution of genes along the chromosomes may be related to gene expression in specific organs or organ systems. In this report we index the subset of genes constituting the human "cardiovascular genome" on chromosomes 21q and 22q as well as report the identification of several "cardiovascular gene" clusters. These gene clusters are suggestive of a higher order of tissue-specific gene regulation at the chromosomal level.

Identification, characterization, and mapping of expressed sequence tags from an embryonic zebrafish heart cDNA library

The generation of expressed sequence tags (ESTs) has proven to be a rapid and economical approach by which to identify and characterize expressed genes. We generated 5102 ESTs from a 3-d-old embryonic zebrafish heart cDNA library. Of these, 57.6% matched to known genes, 14.2% matched only to other ESTs, and 27.8% showed no match to any ESTs or known genes. Clustering of all ESTs identified 359 unique clusters comprising 1771 ESTs, whereas the remaining 3331 ESTs did not cluster. This estimates the number of unique genes identified in the data set to be approximately 3690. A total of 1242 unique known genes were used to analyze the gene expression patterns in the zebrafish embryonic heart. These were categorized into seven categories on the basis of gene function. The largest class of genes represented those involved in gene/protein expression (25.9% of known transcripts). This class was followed by genes involved in metabolism (18.7%), cell structure/motility (16.4%), cell signaling and communication (9.6%), cell/organism defense (7.1%), and cell division (4.4%). Unclassified genes constituted the remaining 17.91%. Radiation hybrid mapping was performed for 102 ESTs and comparison of map positions between zebrafish and human identified new synteny groups. Continued comparative analysis will be useful in defining the boundaries of conserved chromosome segments between zebrafish and humans, which will facilitate the transfer of genetic information between the two organisms and improve our understanding of vertebrate evolution.

Optimal low dosage of acetylsalicylic acid (ASA) for the prevention and treatment of ischemic cerebrovascular disease in geriatric patients

A series of 108 geriatric patients with ischemic cerebrovascular disease were treated with low dose aspirin (acetylsalicylic acid, ASA). Daily doses of 100 mg, 50 mg and 25 mg were administered to three groups of 36 patients. Changes in platelet aggregation responses were dynamically observed in 64 (22 normal subjects, 42 patients). Monitoring of 22 normal subjects revealed inhibition of platelet aggregation at a dose of 300 mg or 100 mg which could last as long as 7 days. This suggests that 100 mg or less could be clinically effective. Satisfactory inhibitory effects on platelet aggregation were observed in all three groups, with 14 patients in each group given daily doses of 100 mg, 50 mg and 25 mg during four weeks' observation. The most effective inhibition was obtained in the 50 mg group. Therefore, the authors recommend 50 mg/d as the optimal dosage for low dose aspirin therapy in geriatric patients.

[Analysis of 59 cases of non-traumatic sudden death in various neurological diseases]

Sudden death is a common complication of myocardial infarction, necrotic pancreatitis and other diseases. Physicians usually neglect the possibility of neurological disorders. 59 cases of sudden death among 314 autopsied cases with neurological diseases were analyzed. The most frequent cause of neurological sudden death was cerebrovascular disease (CVD). It was present in 53 (89.9%) cases. 48 of them had hemorrhagic CVD. 37 of these 48 cases were due to hypothalamic lesions. In 37 cases general autopsy was performed; pathological abnormalities of heart, lungs, stomach etc, were found in 28 of them. In conclusion, the size and location of the lesion correlated with the prognosis of the disease. Concomitant multiple organ damage may deteriorate the lesion. Awareness of sudden death resulting from CVD may elevate the rate of correct diagnosis.