Slow Learning Curve Research Articles

Robot-assisted Microsurgery: Lessons Learned from 50 Consecutive Cases.

The potential of robot-assisted surgery in plastic and reconstructive surgery remains to be established, especially in free tissue transfer. This prospective study aimed to present our experience and findings from the first 50 consecutive cases of robot-assisted microsurgery using the Symani surgical system. A prospective database was maintained, recording patient demographics and surgical details for all cases of robot-assisted microsurgery in a large academic institution. All surgeons underwent an intensive training program with the Symani surgical system. A total of 50 patients who underwent robot-assisted microsurgical reconstruction were identified. Free microsurgical tissue transfer was performed in 45 cases, targeted muscle reinnervation in four cases, and lymphovenous anastomoses in a single case. A total of 94 robot-assisted anastomoses and coaptations were performed, (46 venous and 30 arterial anastomoses, 16 nerve coaptations, two lymphovenous anastomoses). Six cases involved perforator-to-perforator anastomoses. Ninety-eight percent of attempted anastomoses were completed using the robot. Size-mismatch anastomoses, seen in 37.8% of cases, took significantly longer. Minor complications occurred in three cases and major in six cases. There were three cases of microvascular compromise requiring revision. One partial flap loss and no complete flap loss occurred. Our study highlights the immense potential of robot-assisted microsurgery, and a feasible and effective modality for various microsurgical procedures, with outcomes comparable to those of conventional microsurgery. Despite challenges, such as increased operating times and higher costs, the technology offers significant advantages, such as enhanced precision and motion scaling. We identify a slow learning curve and a necessity for higher caseloads.

Training in retinoscopy: learning curves using a standardized method

BackgroundRetinoscopy is one of the most effective objective techniques for evaluating refractive status, especially in non-cooperative patients. However, it presents a slow learning curve that often leads to student frustration. With the current Covid-19 pandemic and the need for social isolation, clinical education based on simulation has become more relevant. Therefore, we implemented retinoscopy laboratories and learning protocols to reduce student stress and learning time.MethodsWe conducted a study to evaluate the retinoscopy learning curve using a new training protocol proposal. One hundred trainees were assessed in four stages, corresponding to 08, 12, 16, and 20 hours of training. Six different refractive defects were used trying to reproduce frequent conditions of care. The time spent on the assessment was not considered as additional training time. To analyze the data, we used non-parametric statistics and linear regression to assess the variables associated with training time and performance rate.ResultsThe mean performance score at 08 hrs was 32.49% (±16.69 SD); at 12 hrs was 59.75% (±18.80 SD); at 16 hrs was 70.83% (±18.53 SD) and at 20 hrs was 84.26% (±13.18 SD). Performance at 12 hrs was significative higher than 08 hrs of training, but did not show significant differences with the performance rate at 16 and 20 hrs. We found a strong positive correlation between performance and training time in retinoscopy (R = 0.9773, CI: 0.2678 - 0.9995 p = 0.0227).ConclusionThis study showed that an increasing number of hours of practice positively correlates with performance in retinoscopy. The elaboration of a protocol and standardization of performance per hour also allowed us to estimate that a minimum of 13.4 hrs of practice is required to achieve 60% performance. Using the resulting formula, it is possible to determine the number of hours of retinoscopy practice are necessary to reach a certain level of performance.

The Thoracodorsal Artery Perforator Flap for the Treatment of Hidradenitis Suppurativa of the Axilla: A Prospective Comparative Study.

Hidradenitis suppurativa (HS) is a common chronic condition that is often resistant to conservative treatment and requires a wide and aggressive surgical approach to prevent recurrence. A prospective study was performed comparing the outcomes of thoracodorsal artery perforator (TDAP) flap-based reconstruction and secondary intention closure (SIC) after wide local excision (WLE) of axillary HS. A prospective study was conducted on 68 patients with stage 3 axillary HS. Thirty-three patients underwent a WLE procedure and were left to heal by secondary intention (SIC group), and 35 patients underwent immediate reconstruction with a homolateral TDAP flap (TDAP group). Inpatient stay, healing time, postoperative complications rate, and pain were analyzed in both groups, comparing preoperative shoulder function (using Constant-Murley shoulder outcome score) and quality of life (using a dermatology life quality index) with postoperative shoulder function and quality of life. Patients receiving TDAP flaps had significantly faster recovery, fewer complications, and fewer overall number of procedures than those who underwent SIC. All patients reported an improved quality of life after their operation. The TDAP group showed significantly more improvement than the SIC group ( P < 0.001). Patients receiving TDAP flaps reported a significant reduction in pain and discomfort and better shoulder function compared with patients in the SIC group ( P < 0.001). WLE and TDAP flap-based reconstruction for axillary stage 3 HS provide optimal postprocedural functional results with a low complication rate. Complete remission of the disease was observed after the procedure. Despite the relatively slow learning curve of this procedure, the authors strongly recommend this technique as a very good option for the management of stage 3 axillary HS. Therapeutic, II.

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Weighting-Based Deep Ensemble Learning for Recognition of Interventionalists’ Hand Motions During Robot-Assisted Intravascular Catheterization

Robot-assisted intravascular interventions have evolved as unique treatments approach for cardiovascular diseases. However, the technology currently has low potentials for catheterization skill evaluation, slow learning curve, and inability to transfer experience gained from manual interventions. This study proposes a new weighting-based deep ensemble model for recognizing interventionalists' hand motions in manual and robotic intravascular catheterization. The model has a module of neural layers for extracting features in electromyography data, and an ensemble of machine learning methods for classifying interventionalists' hand gestures as one of the six hand motions used during catheterization. A soft-weighting technique is applied to guide the contributions of each base learners. The model is validated with electromyography data recorded during <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-vitro</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-vivo</i> trials and labeled as <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">many-to-one</i> sequences. Results obtained show the proposed model could achieve 97.52% and 47.80% recognition performances on test samples in the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-vitro</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-vivo</i> data, respectively. For the latter, transfer learning was applied to update weights from the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-vitro</i> data, and the retrained model was used for recognizing the hand motions in the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-vivo</i> data. The weighting-based ensemble was evaluated against the base learners and the results obtained shows it has a more stable performance across the six hand motion classes. Also, the proposed model was compared with four existing methods used for hand motion recognition in intravascular catheterization. The results obtained show our model has the best recognition performances for both the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-vitro</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-vivo</i> catheterization datasets. This study is developed toward increasing interventionalists' skills in robot-assisted catheterization.

Counting microalgae cultures with a stereo microscope and a cell phone using deep learning online resources

BackgroundThis work presents an experience done to evaluate the number of very small objects in the field of view of a stereo microscope, which are usually counted by direct observation, with or without the use of grids as visual aids. We intend to show that deep learning recent algorithms like YOLO v5 are adequate to use in the evaluation of the number of objects presented, which can easily reach the 1000 s. This kind of algorithm is open-source software, requiring a minimum of skills to install and run on a regular laptop. We further intend to show that the robustness of these kinds of approaches using convolutional neural networks allowed for the use of images of less quality, such as the images acquired with a cell phone.ResultsThe results of training the algorithm and counting microalgae in cell phone images were assessed through human curation in a set of test images and showed a high correlation, showing good precision and accuracy in detections.ConclusionsThis is a low-cost alternative available worldwide to many more facilities than expensive cameras and high-maintenance rigid set-ups, along with software packages with a slow learning curve, therefore enlarging the scope of this technique to areas of knowledge where the conditions of laboratory and human work are a limiting factor.

Accuracy determination using deep learning technique in cloud-based IoT sensor environment

The Internet of Things (IoT) offers users a wide variety of facilities because it interconnects billions of smart devices. However, when connected to wireless connections, unlimited access to IoT gadgets poses potential risks. As it eases cost constraints on sensor nodes, the cloud service with IoT networks has received greater attention. In addition, the high complexity of the distribution and networking of IoT makes them vulnerable to attacks. Intrusion detection systems (IDSs) are selected to ensure the security of reliable information and operations. IDS successfully detects anomalies in complex network situations and guarantees network security. Deep Convolution Network (DCN) IDS have a slow learning curve and poor categorization precision. Deep Learning (DL) methods are often used in a wide range of safety data processing, imaging, and signal processing like Poor transfer learning ability, reusability of modules, and integration. To overcome the constraints of Machine Learning (ML) IDS is intended to provide a comprehensive mechanism to learn the detection mechanism for multicloud IoT environments. The proposed IDS approach increases training efficiencies while increasing detection accuracy. Experimental investigations of the proposed system using the considered database confirms that the performance of the proposed system is capable and in the range of acceptance with relative to existing methods. Further, achieving detection capability, reliability, and accuracy of 97.51, 96.28, and 94.41% respectively are achieved.

Slow or sudden: Re-interpreting the learning curve for modern systems neuroscience.

Learning is fundamental to animal survival. Animals must learn to link sensory cues in the environment to actions that lead to reward or avoid punishment. Rapid learning can then be highly adaptive and the difference between life or death. To explore the neural dynamics and circuits that underlie learning, however, has typically required the use of laboratory paradigms with tight control of stimuli, action sets, and outcomes. Learning curves in such reward-based tasks are reported as slow and gradual, with animals often taking hundreds to thousands of trials to reach expert performance. The slow, highly variable, and incremental learning curve remains the largely unchallenged belief in modern systems neuroscience. Here, we provide historical and contemporary evidence that instrumental forms of reward-learning can be dissociated into two parallel processes: knowledge acquisition which is rapid with step-like improvements, and behavioral expression which is slower and more variable. We further propose that this conceptual distinction may allow us to isolate the associative (knowledge-related) and non-associative (performance-related) components that influence learning. We then discuss the implications that this revised understanding of the learning curve has for systems neuroscience.

Deep Reinforcement Learning Algorithms for Path Planning Domain in Grid-like Environment

Recently, more and more solutions have utilised artificial intelligence approaches in order to enhance or optimise processes to achieve greater sustainability. One of the most pressing issues is the emissions caused by cars; in this paper, the problem of optimising the route of delivery cars is tackled. In this paper, the applicability of the deep reinforcement learning algorithms with regards to the aforementioned problem is tested on a simulation game designed and implemented to pose various challenges such as constant change of delivery locations. The algorithms chosen for this task are Advantage Actor-Critic (A2C) with and without Proximal Policy Optimisation (PPO). These novel and advanced reinforcement learning algorithms have yet not been utilised in similar scenarios. The differences in performance and learning process of those are visualised and discussed. It is demonstrated that both of those algorithms present a slow but steady learning curve, which is an expected effect of reinforcement learning algorithms, leading to a conclusion that the algorithms would discover an optimal policy with an adequately long learning process. Additionally, the benefits of the Proximal Policy Optimisation algorithm are proven by the enhanced learning curve with comparison to the Advantage Actor-Critic approach, as the learning process is characterised by faster growth with a significantly smaller variation. Finally, the applicability of such algorithms in the described scenarios is discussed, alongside the possible improvements and future work.

Reducing the Soleus Stretch Reflex With Conditioning: Exploring Game- and Impedance-Based Biofeedback.

People with spasticity, i.e., stretch hyperreflexia, have a limited functional independence and mobility. While a broad range of spasticity treatments is available, many treatments are invasive, non-specific, or temporary and might have negative side effects. Operant conditioning of the stretch reflex is a promising non-invasive paradigm with potential long-term sustained effects. Within this conditioning paradigm, seated participants have to reduce the mechanically elicited reflex response using biofeedback of reflex magnitude quantified using electromyography (EMG). Before clinical application of the conditioning paradigm, improvements are needed regarding the time-intensiveness and slow learning curve. Previous studies have shown that gamification of biofeedback can improve participant motivation and long-term engagement. Moreover, quantification of reflex magnitude for biofeedback using reflexive joint impedance may obtain similar effectiveness within fewer sessions. Nine healthy volunteers participated in the study, split in three groups. First, as a reference the “Conventional” group received EMG- and bar-based biofeedback similar to previous research. Second, we explored feasibility of game-based biofeedback with the “Gaming” group receiving EMG- and game-based biofeedback. Third, we explored feasibility of game- and impedance-based biofeedback with the “Impedance” group receiving impedance and game-based biofeedback. Participants completed five baseline sessions (without reflex biofeedback) and six conditioning sessions (with reflex biofeedback). Participants were instructed to reduce reflex magnitude without modulating background activity. The Conventional and Gaming groups showed feasibility of the protocol in 2 and 3 out of 3 participants, respectively. These participants achieved a significant Soleus short-latency (M1) within-session reduction in at least –15% in the 4th–6th conditioning session. None of the Impedance group participants showed any within-session decrease in Soleus reflex magnitude. The feasibility in the EMG- and game-based biofeedback calls for further research on gamification of the conditioning paradigm to obtain improved participant motivation and engagement, while achieving long-term conditioning effects. Before clinical application, the time-intensiveness and slow learning curve of the conditioning paradigm remain an open challenge.

Robot-assisted pyeloplasty using a new robotic system, the KangDuo-Surgical Robot-01: a prospective, single-centre, single-arm clinical study.

Open Anderson-Hynes dismembered pyeloplasty was the criterion standard for ureteropelvic junction obstruction. Laparoscopic pyeloplasty was comparable to open pyeloplasty in success rates while laparoscopic pyeloplasty offered the advantages of decreased morbidity, shorter hospital stay, and quicker recovery. While laparoscopic pyeloplasty was accompanied with the slow learning curve due to technically demanding and time-consuming intracorporal suturing, which has limited its widespread use. Robotic pyeloplasty and laparoscopic pyeloplasty were comparable regarding complication rate, success rate and operative time.

The evolution of corporate reporting on GHG emissions: A Canadian portrait

This paper examines the evolution of the extent to which firms with a high greenhouse gases (GHG) emission impact complied with Chartered Professional Accountants (CPA) Canada guidelines on climate change disclosures, as well as the factors that influenced these disclosures. The sample is comprised of Canadian firms in the mining, energy, and chemical sectors. The study measures the influence of the firms’ political exposure and media visibility, their audit firm, the presence of an environment committee, their ownership structure, and their financial performance on their GHG emissions disclosures. Our findings show that these disclosures considerably evolved over the 10 year period from 2007 to 2017 and that this evolution was in the form of a leap rather than a slow and steady learning curve. We also confirmed the significant influence of the environment committee, political exposure, and media visibility on this evolution. Our empirical results corroborate the work of DiMaggio and Powell (1983), outlining the important role normative pressures play in voluntary GHG emissions disclosure firms make in order to secure the legitimacy conferred by society (Suchman, 1995)

Liver Parenchyma Transection-First Approach for Laparoscopic Left Hemihepatectomy: A Propensity Score Matching Analysis.

Laparoscopic major liver resection, such as laparoscopic left hemihepatectomy (LLH), is still perceived as a complicated procedure due to technical difficulties and slow learning curve. The study introduced an optimized procedure using the liver parenchyma transection-first approach and investigated its advantages on surgical outcomes by comparison with the conventional hilar dissection approach for LLH. Between January 2015 and May 2019, 96 patients who underwent laparoscopic left hemihepatectomy for hepatocellular carcinoma (HCC) were enrolled in the study. Among these, 41 patients underwent theliver parenchyma transection-first approach (LP-first group) and the other 55 underwent the conventional hilar dissection approach (conventional group). A 1:1 propensity score matching (PSM) was performed to compare the perioperative and long-term oncological outcomes of the two groups. After 1:1 PSM, 37 patients in each group were selected for further analysis. The LP-first group was associated with shorter median operative time (210 vs 235min, P = 0.035) and less blood loss (200 vs 300mL, P = 0.410). In addition, no statistical differences were found in overall complications between the two groups (8.1% vs 24.3%, P = 0.058). There were no significant differences between the two groups in terms of 1-year and 3-year disease-free survival (DFS, P = 0.608) and overall survival (OS, P = 0.414). The prior liver parenchyma approach for LLH is safe and reproducible in selected patients, which showed improved perioperative outcomes and comparable long-term oncological outcomes compared with the conventional approach.

Minimally-invasive parasternal aortic valve replacement-A slow learning curve towards improved outcomes.

We report our starting experience with parasternal minimally-invasive aortic valve replacement. From 7/14 to 8/18, 192 received classic aortic valve surgery using a 5 cm parasternal incision and percutaneous groin cannulation. Patients were selected based on anatomic feasibility judged by preoperative computed tomography-scan. Except for porcelain aorta, left-sided aortic location, or endocarditic abscess, there were no exclusions. Patients were divided into two groups (first and second half of experience). Demographics were equal. Patients' mean ejection fraction was 59%, with preoperative stroke (12%), severe chronic obstructive pulmonary disorder(11%), and endocarditis (2%). All cases were elective or urgent. The Euroscore II was 3.37 ± 3.31 in the first and 3.68 ± 3.97 in the second group (n.s.). Biological prostheses were implanted in 90%. Operating times in the first group were just under 3 hours, with bypass times of 129 ± 32 minutes and clamp times of 77 ± 20 minutes. In the second group, these times changed only minimally. There were three conversions to sternotomy in the first, but only one in the second group. Similarly, three patients died in the first and one in the second group. There were fewer complications in the second group regarding revision for bleeding (7 vs 1%), stroke (4 vs0%) dialysis (3 vs1%), and pericardial effusions (3 vs1%). The O/E ratio dropped from 0.93 to 0.28. Parasternal minimally-invasive aortic valve replacement is a feasible technique associated with a slow learning curve but the potential to achieve improved outcomes. Considering the transcatheter alternatives, the relative risk reduction may be worth investigating in future trials.

Endoscopic applications of magnets for the treatment of gastrointestinal diseases

Endoscopic treatment of gastrointestinal diseases has developed rapidly in recent years, due to its minimally invasive nature. One of the main contributing factors for this progress is the improvement of endoscopic instruments, which are essential for facilitating safe and effective endoscopic interventions. However, the slow learning curve required in the implementation of many advanced endoscopic procedures using standard devices is associated with a high risk of complications. Other routine procedures may also be complicated by unexpected difficulties. Based on the ferromagnetic properties of many objects, both internal and external magnetic devices have been developed and applied for multiple endoscopic interventions. The applications of magnets, mainly including compression, anchoring and traction, facilitate many difficult procedures and make it feasible to operate procedures that were previously impossible. Other novel endoscopic applications, such as magnetic nanoparticles, are also under development. In this article, we reviewed published studies of endoscopic applications of magnets for the treatment of gastrointestinal diseases such as precancerous lesions and cancer, obstruction, stricture, congenital and acquired malformations, motility disorders, and ingestion of foreign bodies. Since several endoscopic applications of magnets may also be relevant to surgery, we included them in this review.

Atrophic vulvar lichen sclerosus evolving to an epidermoid carcinoma: about an uncommon case

Malignant tumors of the vulva are usually budding, ulcerated, or infiltrating. The fear of cancer must always be in mind, in front of any vulvar lesion. Therefore, do not hesitate to make biopsies of any lesion of the vulva to confirm or deny a cancer. We hereby report the uncommon case of a postmenopausal 68-old-patient followed for an atrophic vulvar lichen sclerosus which eventually transformed into an epidermoid carcinoma of the vulva. The indication for right hemivulvectomy with sentinel lymph node procedure was retained. Vulvar cancer takes a variety of aspects. It is therefore necessary to always have it in mind and to make a biopsy before any suspicious lesion. Since the atrophic vulvar lichen sclerosus of the vulva is a pre-cancerous lesion, we believe that its follow-up must be strict and a second biopsy must be performed before any worsening of the lesions. Finally, the procedure of the sentinel lymph node is of great interest when we know the morbidity of the inguinal region dissections but also the slow learning curve of surgical techniques of vulvar cancer.

Sonography of the Outflow Tracts of the Fetal Heart Part 1 – Normal Anatomy and Common Anatomical Variants

The four-chamber view of the fetal heart is still widely used as the only sonographic view for detection of congenital heart disease (CHD). However, inherent limitations of the four-chamber view in detecting abnormalities of the major vessels necessitate expanding the routine scan to include the outflow tracts. Conotruncal abnormalities in particular are often not detected on the four-chamber view. Assessment of the heart and outflow tracts is accomplished by sequential transverse planes starting in the upper abdomen and ending in the superior mediastinum. Grey-scale 2-D images, complemented by colour and pulsed Doppler which help quantify direction and velocity flow within the insonated vessel are now considered the standard. Although there is initially a steep, slow learning curve, successful evaluation of the outflow tracts can be accomplished within 5 minutes by an experienced examiner. Grey-scale images complemented by colour, directional power Doppler and pulsed Doppler will allow identification of most major CHD cases. This paper describes the normal anatomy in each of these transverse planes, as well as common variants and pitfalls that constitute the normal two-dimensional scan, that must be mastered prior to evaluating the numerous abnormalities that may be encountered. Most infants with CHD are born to mothers without specifically defined risk factors, and it is for this reason, that the emphasis on fetal heart evaluation has evolved to routine screening of both low- and high-risk pregnancies. The four-chamber view of the fetal heart is still widely used as the only sonographic view for detection of congenital heart disease (CHD). However, because of the inherent limitations in the four-chamber view in detecting anomalies of the outflow tracts, the sensitivity for detection of CHD varies from 48 to 63% in some series.1-3 When evaluation of the outflow tracts is performed as well, the detection rate of CHD increases to over 90%.4

Analysis of the learning curve of the surgical procedure for the treatment of thoracic disc herniation using anterolateral transthoracic approach with the aid of image-guided system.

In surgery, the learning process represents one of the critical topics in the development of a young surgeon where there is often no standardized learning program. The learning curve is defined by plotting proficiency as a function of time, or the number of repetitions. In this study, we analyzed the learning process for a rare and surgically demanding pathology such as thoracic disc herniations (TDHs) treated with an antero-lateral trans-thoracic approach. We analyzed a consecutive series of patients admitted with a diagnosis of TDHs. All patients underwent surgery using a standard antero-lateral trans-thoracic approach, assisted by navigation system based on intraoperative 3D imaging performed with O-Arm™ (Medtronic; Dublin, Ireland) system. Twenty-one patients underwent surgery from January 2012 to June 2017. The time analysis shows a progressive reduction in time from the first to the last case with continued improvement in operating time but progressively less dramatic, this is explicable considering the classic learning curve model. Predictably, a slow learning curve was charted - typical for a technically demanding procedure associated with a rare incidence of pathology. A learning curve is an easy and efficient way to gauge the growth of a surgeon. After 21 cases we obtained an intermediate profile of learning curve between steep and shallow. Despite different alternatives for speeding up the learning process it is not always possible to standardize and reflect them in a learning process. Today, the use of technology is often considered in this but does not always affect the process itself.

The Röttinger approach for total hip arthroplasty: technique, comparison to the direct lateral approach and review of literature.

Multiple approaches to the hip joint have been developed utilizing various intervals and/or intermuscular planes when performing a total hip arthroplasty (THA), each proposing certain advantages. Of these, the Röttinger approach (modified anterolateral or Watson-Jones) is potentially muscle-sparing. Multiple studies have demonstrated favorable outcomes with this approach. However, others showed more complications with a slow learning curve. Due to the paucity of evidence we conducted this study to: (I) present our operative experience and technique of the Röttinger approach; (II) compare short-term complications and operative room (OR) times of this approach to the direct lateral; and (III) review the available literature. This was a review of a longitudinally maintained single-surgeon database of patients who underwent primary THA using either the Röttinger or direct lateral approach. A total of 100 consecutive patients (100 hips) who underwent primary unilateral THA using the Röttinger approach between April 1st, 2012 and April 30th, 2015 were identified. These patients were compared to another cohort of 147 consecutive patients (147 hips) who underwent the procedure using the direct lateral approach (of Hardinge). The operative technique for the Röttinger approach involves accessing the hip joint through muscle-sparing technique between the tensor fascia lata and gluteus medius muscles. We evaluated and compared the short-term complications and the mean operative times for each cohort. In addition, we performed a literature search on the clinical studies that reported on the Röttinger approach using the following databases; PubMed, EMBASE, EBSCO Host, and SCOPUS. Studies published between January 1st of 2000 and September 1st of 2017 were reviewed. We included only studies that compared this approach to other standard approaches and excluded single-cohort case series, case reports, cadaveric studies, and studies not in English language. At mean follow-up time of 12 weeks (range, 6 to 24 weeks), there were two patients in the Röttinger cohort who experienced lateral femoral cutaneous nerve palsies (2%), which were self-limited and resolved at 6 and 12 weeks. In the direct lateral cohort, there was one hip dislocation (2%) at 6 weeks post-operatively, which was successfully managed by a closed reduction. In patients who received the Röttinger approach, mean OR time was 130 minutes (range, 74 to 202 minutes), compared to the direct lateral cohort mean of 111 minutes (range, 71 to 222 minutes). Our literature analysis covered 2,252 patients who received the Röttinger approach vs. 19,941 patients who underwent variety of other standard approaches including anterior, direct lateral, and posterior. At final follow up (range, 6 to 52 months), patients who underwent the Röttinger approach demonstrated comparable clinical outcomes and complications to patients who underwent primary THA using other approaches. In this analysis of a single-surgeon experience of the Röttinger approach compared to the direct lateral, we presented our experience with the technique and demonstrated the safety and feasibility of this relatively novel approach. Our study results demonstrated that patients who underwent this approach had similar short-term complications and OR times to those who underwent the direct lateral approach. Additionally, our findings agree with previous comparative studies that demonstrated similar outcomes of this approach. Therefore, it can be used as an alternative for primary THA.

Our experience in first 100 cases of endoscopic carpal tunnel release: An Indian perspective

PurposeThis study was done to determine the role of endoscopic carpal tunnel release in the treatment of carpal tunnel syndrome and also to note the conversion rates of endoscopic to open release, causes for conversion and to analyse the learning curve of the operating surgeon for endoscopic procedure. MethodsA total of 100 consecutive idiopathic carpal tunnel cases were included who had undergone preoperative ultrasonography (USG) for assessment of carpal tunnel morphology. All patients were primarily scheduled for a standard single portal endoscopic release after excluding the contraindications for endoscopic carpal tunnel release (ECTR). The conversion rate of endoscopic to open carpal tunnel release (OCTR) was analysed and reasons for conversion were established by an independent observer. ResultsOut of 100 patients, 74 (74%) underwent endoscopic release and 26(26%) underwent mini-open release. The conversion rates from endoscopy to open was noted to be 26%. Distal edge not being visualized in 14 cases (53%) was the most common cause for conversion followed by tight canal hindering the insertion of the scope in four cases (15.3%). In the first fifty cases in our study, 20 cases were converted to open release which amounted to 40% conversion rate, but in the next 50 subset of patients the conversion rates had dropped to 13.3%. ConclusionEndoscopic carpal tunnel release can be accepted as the treatment of choice for the surgical decompression of carpal tunnel owing to decreased postoperative complications. One of the major limitations of the ECTR is the slow learning curve of a surgeon. Difficulty to visualise the distal edge of TCL was most common cause for conversion. With increasing experience of a surgeon in endoscopic release, the conversion rates would decrease.Level of study: level 4, decision analysis