Surgical Precision Research Articles

Robot-Assisted Epiretinal Membrane Peeling: A Prospective Assessment of Pre- and Intra-Operative Times and of Surgeons' Subjective Perceptions.

The Preceyes Surgical System (PSS) is a robotic assistive device that may enhance surgical precision. This study assessed pre- and intra-operative times and surgeons' perceptions of robot-assisted epiretinal membrane peeling (RA-MP). We analyzed the time requirement of three main tasks: the preparation of the PSS (I), patient preparation (II), and surgery (III). Following surgery, the surgeons were asked questions about their experience. RA-MP was performed in nine eyes of nine patients. Task I required an average time of 12.3 min, initially taking 15 min but decreasing to 6 min in the last surgery. Task II showed a mean time of 47.2 (range of 36-65) min. Task III had a mean time of 72.4 (range of 57-100) min. A mean time of 27.9 (range of 9-46) min was necessary for RA-MP. The responses to the questionnaire revealed a trend towards increasing ease and reduced stress as familiarity with the PSS increased. A substantial reduction in pre- and intra-operative times, decreasing to a total of 115 min, was demonstrated. RA-MP was positively anticipated by the surgeons and led to no hand or arm strain while being more complex than manual MP.

Skull-Base Surgery-A Narrative Review on Current Approaches and Future Developments in Surgical Navigation.

Surgical navigation technology combines patient imaging studies with intraoperative real-time data to improve surgical precision and patient outcomes. The navigation workflow can also include preoperative planning, which can reliably simulate the intended resection and reconstruction. The advantage of this approach in skull-base surgery is that it guides access into a complex three-dimensional area and orients tumors intraoperatively with regard to critical structures, such as the orbit, carotid artery and brain. This enhances a surgeon's capabilities to preserve normal anatomy while resecting tumors with adequate margins. The aim of this narrative review is to outline the state of the art and the future directions of surgical navigation in the skull base, focusing on the advantages and pitfalls of this technique. We will also present our group experience in this field, within the frame of the current research trends.

New technologies in the surgical management of endometriosis

Introduction: Endometriosis is a very common disease that affects up to 10% of the female population. Although medical therapy represents the first-line treatment for endometriosis, it does not always manage to control symptoms. Laparoscopy represents the standard surgical treatment in endometriosis. Robotic-assisted laparoscopy is an innovative mini-invasive surgical technique. Its application in gynecological surgery and in endometriosis has increased in the last decade. Our purpose is to offer an overview of the role of robotic-assisted laparoscopy in the surgical treatment of endometriosis. Methods: We evaluated studies dealing with the new technique in surgery for endometriosis with a focus on robotic surgery. We performed a compressive literature research on PubMed and the Cochrane Library in December 2022. Expert opinion: Robotic-assisted surgery is a feasible and safe approach to endometriosis surgery and is superimposable to laparoscopy in terms of complication rate, blood loss, hospitalization, and long-term improvement of symptoms. The effect of robotic-assisted surgery on operative time is still contradictory and needs to be further investigated. Robotic-assisted laparoscopic surgery can provide particular benefit in the management of women with severe endometriosis secondary to its advantage in surgical precision and ergonomics. Indocyanine green fluorescence angiography could be useful to assist in the vascularization of ureters and bowel anastomosis, to prevent postoperative complication and leakage.

Cavernous Malformations: What They Have Taught Us.

Cavernous Malformations: What They Have Taught Us.

Application of Virtual Reality Systems in Bone Trauma Procedures.

Background and Objectives: Bone fractures contribute significantly to the global disease and disability burden and are associated with a high and escalating incidence and tremendous economic consequences. The increasingly challenging climate of orthopaedic training and practice re-echoes the established potential of leveraging computer-based reality technologies to support patient-specific simulations for procedural teaching and surgical precision. Unfortunately, despite the recognised potential of virtual reality technologies in orthopaedic surgery, its adoption and integration, particularly in fracture procedures, have lagged behind other surgical specialities. We aimed to review the available virtual reality systems adapted for orthopaedic trauma procedures. Materials and Methods: We performed an extensive literature search in Medline (PubMed), Science Direct, SpringerLink, and Google Scholar and presented a narrative synthesis of the state of the art on virtual reality systems for bone trauma procedures. Results: We categorised existing simulation modalities into those for fracture fixation techniques, drilling procedures, and prosthetic design and implantation and described the important technical features, as well as their clinical validity and applications. Conclusions: Over the past decade, an increasing number of high- and low-fidelity virtual reality systems for bone trauma procedures have been introduced, demonstrating important benefits with regard to improving procedural teaching and learning, preoperative planning and rehearsal, intraoperative precision and efficiency, and postoperative outcomes. However, further technical developments in line with industry benchmarks and metrics are needed in addition to more standardised and rigorous clinical validation.

Cutting-edge patient-specific surgical plates for computer-assisted mandibular reconstruction: The art of matching structures and holes in precise surgery.

Cutting-edge patient-specific surgical plates (PSSPs) are supposed to improve the efficiency, precision, and functional outcomes of mandibular reconstruction. This study characterized the premium role of PSSPs in precise surgery and explored their working principles in computer-assisted mandibular reconstruction (CAMR). The PSSPs-enhanced surgical precision was investigated through the model surgery and representative cases. Spatial deviations of reconstruction were characterized by comparing the reconstructed mandible with the virtually designed mandible. Working principles of PSSPs were distinguished by a review of evolving surgical techniques in CAMR. In the model surgery, spatial deviations between the virtually planned mandible and the reconstructed mandible were 1.03 ± 0.43 mm in absolute distance deviation, 1.70 ± 1.26 mm in intercondylar length, and 1.86 ± 0.91 mm in intergonial length in the study group of PSSPs, significantly smaller than in the control group of conventional prebent surgical plates. Meanwhile, in the study group, distance deviations were 0.51 ± 0.19 mm in bone-plate distance and 0.56 ± 0.28 mm in drilled screw holes, indicating the art of matching structures and holes. The PSSPs-enhanced CAMR was further demonstrated in three representative cases of mandibular reconstruction. Finally, four primary techniques of CAMR were summarized based on a review of 8,672 articles. The premium role of PSSPs was distinguished by the benefits of matching structures and holes. The PSSPs-enhanced surgical precision was verified through the model surgery and demonstrated in human surgery. Compared to other surgical techniques of CAMR, PSSPs contributed to the precise surgery by the art of matching structures and holes.

Mechanisms and Treatments of Peripheral Nerve Injury.

Peripheral nerve injury is a common injury disease. Understanding of the mechanisms of periphery nerve repair and regeneration after injury is an essential prerequisite for treating related diseases. Although the biological mechanisms of peripheral nerve injury and regeneration have been studied comprehensively, the clinical treatment methods are still limited. The bottlenecks of the treatments are the shortage of donor nerves and the limited surgical precision. Apart from the knowledge regarding the fundamental characteristics and physical processes of peripheral nerve injury, numerous studies have found that Schwann cells, growth factors, and extracellular matrix are main factors affecting the repair and regeneration process of injured nerves. At present, the therapeutical methods of the disease include microsurgery, autologous nerve transplantation, allograft nerve transplantation and tissue engineering technology. Tissue engineering technology, which combines seed cells, neurotrophic factors, and scaffold materials together, is promising for treating the patients with long-gapped and large nerve damage. With the development of neuron science and technology, the treatment of peripheral nerve injury diseases will continue being improved.

In Vitro Testing and Clinical Handling of a Novel Implant Positioning Technology for Proximal Humeral Plating.

Fractures of the proximal humerus are common, particularly in elderly populations. Anatomical locking plates target stabilization with a multitude of screws spanning into the humeral head. Sound implant placement and screw length determination are key for a successful clinical outcome but are difficult to obtain from planar X-rays. A novel implant positioning technology for proximal humerus plating (Xin1) outputs screw lengths suggestions and plate position based on hole projections in conventional X-ray images. This study investigated the performance of a prototype Xin1 system in a postmortem (in vitro) experiment as well as in a clinical handling test. For in vitro testing, twelve shoulders from six anatomical specimens were randomized into two groups to compare the Xin1 technique to the conventional operation in terms of surgical precision, procedure time and X-ray exposure. For the clinical trial, 11 patients undergoing plating of the proximal humerus were included. The aim was to investigate clinical handling of the Xin1 marker clip and to retrospectively evaluate the system performance in a real-life fracture situation. Image pairs before and after insertion of the proximal screws were retrospectively processed to investigate the influence of potential bone fragment shifts on the system output. In the postmortem experiment, the use of the system significantly improved the surgical precision (52% error reduction), procedure time (38% shorter) and radiation exposure (64% less X-rays). Clinical handling demonstrated seamless embedding of the marker clip into existing clinical workflows without adverse events reported. Retrospective X-ray analysis on six eligible patients revealed differences in the calculated screw lengths of ≤2 mm before and after screw insertion for five patients. In one patient, the screw lengths differed up to 8 mm, which might indicate displacement of the head fragment. Results suggest a strong potential of the Xin1 assistance technology to enhance the surgical procedure and patient outcomes in the rising incidence of osteoporotic humeral fractures. Robust performance in a real-life fracture situation was observed. In-depth validation of the system is, however, needed before placing it into clinical practice.

The Role of Advanced Imaging in Neurosurgical Diagnosis.

Neurosurgery as a specialty has developed at a rapid pace as a result of the continual advancements in neuroimaging modalities. With more sophisticated imaging options available to the modern neurosurgeon, diagnoses become more accurate and at a faster rate, allowing for greater surgical planning and precision. Herein, the authors review the current heavily used imaging modalities within neurosurgery, weighing their strengths and weaknesses, and provide a look into new advances and imaging options within the field. Of the many imaging modalities currently available to the practicing neurosurgeon, magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography (PET), and ultrasonography (US) are used most heavily within the field for appropriate diagnosis of neuropathologies in question. For each, their strengths are weighed regarding appropriate capabilities in accurate diagnosis of cranial or spinal lesions. Reasoning for choosing one over the other for various pathologies is also reviewed. Current limitations of each is also assessed, providing insight for possible improvement for each. New advancements in imaging options are subsequently reviewed for best uses within neurosurgery, including the new utilization of FIESTA sequencing, glymphatic mapping, black-blood MRI, and functional MRI. The specialty of neurosurgery will continue to heavily rely on improvements within imaging options available for improved diagnosis and greater surgical outcomes for the patients treated. The synthesis of techniques provided herein may provide meaningful guidance for neurosurgeons in effectively diagnosing neurological pathologies while also helping guide future efforts in neuroimaging developments.

Surgical Precision Analysis of Orthognathic Surgery Combined With Invisible Orthodontic.

This study aimed to explore the changes in hard tissue after applying invisible orthodontic-orthognathic treatment and the digital design, and to explore the accuracy of the treatment effect of maxillofacial tissue after invisible orthodontic treatment and orthognathic treatment. From September 2020 to January 2022, 25 patients with class III skeletal malocclusion and 7 patients with class II skeletal malocclusion, were treated with invisible orthodontic treatment and orthognathic combined treatment. Orthodontic treatment with preoperative invisible orthodontic treatment followed by orthodontic surgery. All patients had cephalometric lateral films after surgery to analyze orthognathic surgery's goals and surgical effects of orthognathic surgery and the digital design. Measure the angle of the sella-nasion-A point angle, angle of sella-nasion-B point, ANB angle, maxillary convex angle, mandibular plane (MP) angle, 1-SN angle, 1-MP angle, etc, and compare surgery outcome with digital design. All patients were satisfied with the effect and no complications occurred. Angle of sella-nasion-A point, angle of sella-nasion-B point, ANB angle, maxillary convex angle, MP angle, 1-SN angle, and 1-MP angle had no significant difference between the postoperative effect and the purpose of digital design ( P >0.05), there was no apparent deviation between the upper and lower jaw and the chin ( P >0.05). The combined invisible orthodontic treatment and orthognathic treatment are accurate and effective, and are worthy of promotion. It supplements traditional orthognathic therapy and is suitable for corresponding patients.

The risk factors of biliary fistula after radical resection of perihilar cholangiocarcinoma in elderly patients and its influence on prognosis: a retrospective cohort study.

Nowadays, the incidence of perihilar cholangiocarcinoma (PHCC) is increasing yearly, and biliary fistula is a common complication. However, there are few reports on the factors affecting the occurrence of biliary fistula. This study aimed to analyze the risk factors for the occurrence of biliary fistula after radical surgery for PHCC in elderly patients to provide a reference basis for improving the prognosis. From April 2016 to April 2021, we randomly included 250 elderly patients with pathologically diagnosed PHCC. Based on our established inclusion and exclusion criteria, we included 211 patients finally Bile drainage for 3 consecutive days after abdominal drainage or single bile drainage ≥100 mL/d was used as the diagnostic criteria for biliary fistula. Multiple logistic regression was used to analyze the independent risk factors for biliary fistula after radical surgery for PHCC. Besides, the Prognostic Score (PS), the Karnofsky performance score (KPS), and the quality of life (QOL) score were used to assess the patients' postoperative recovery, and survival curves were drawn to reflect their 1-year survival rate, using overall survival. The statistical results showed a 36.5% incidence of biliary fistula. Our study showed that preoperative cholangitis, number of biliary anastomoses, etc. were independent risk factors for grade B and grade C biliary fistula. Besides, the presence of intraoperative hemorrhage (OR =0.223, P=0.006) and γ-glutamyl transpeptidase (γ-GT) on the first postoperative day (OR =1.011, P=0.013) were still independent risk factors for grade B biliary fistula, while C-reactive protein (CRP) (OR =1.026, P=0.011) and total bilirubin (TBil) (OR =0.003, P=1.066) on the first postoperative day and bile duct diameter (OR =0.299, P=0.020) were independent risk factors for grade C biliary fistula. Analysis of variance (ANOVA) showed statistically significant differences (P<0.05) between the three groups in terms of PS (P=0.000), KPS (P=0.001), and QOL scores (P=0.000). The incidence of postoperative biliary fistula remains high in elderly patients treated with radical surgery for PHCC and seriously affects their prognosis. Therefore, focusing on the clinical characteristics and risk factors of patients, improving surgical precision and enhancing postoperative patient care to reduce the likelihood of postoperative biliary fistula, thereby prolonging patient life.

Lower Eyelid Blepharoplasty: Minimizing Complications and Correction of Lower Eyelid Malposition.

Lid retraction is a feared complication of lower blepharoplasty. Anatomical variations like negative orbital vector, horizontal lid laxity, and preexisting lid retraction are more prone to lid malpositions. Meticulous and precise execution of a series of surgical steps is key to preventing complications. This includes minimizing surgical trauma, meticulous hemostasis, preserving innervation to the medial lid and pretarsal orbicularis, safe method of fat excision, septal tightening while maintaining lid traction, and conservative and titrated skin excision. Canthal fixation addresses lid laxity and maintains the lid stretched vertically while postoperative healing and fibrosis are taking place. Post-blepharoplasty lid retraction may occur due to failure to address lid laxity and the occurrence of middle lamellar fibrosis. Excessive skin excision may also result in anterior lamellar deficiency. The "sag and drag" concept is useful to evaluate the post-blepharoplasty retracted lid. The treatment of the retracted lid includes lid massage, replacing the anterior lamella, or releasing the middle lamellar fibrosis or a combination of techniques. In conclusion, understanding the mechanisms of lid retraction, careful preoperative assessment, and surgical precision will help surgeons to prevent and manage this complication.

Spatial normalization discrepancies between native and MNI152 brain template scans in gamma ventral capsulotomy patients

In neurosurgery, spatial normalization emerged as a tool to minimize inter-subject variability and study target point locations based on standard coordinates. The Montreal Neurological Institute's 152 brain template (MNI152) has become the most widely utilized in neuroimaging studies, but has been noted to introduce partial volume effects, distortions, and increase structure size in all directions (x/y/z axes). These discrepancies question the accuracy of the MNI template, as well as its utility for studies that examine and form conclusions from group-level data. Given that surgical precision in obsessive-compulsive disorder is essential to patient outcomes, we retrospectively investigated lesion size and location in patients (n = 21) who underwent capsulotomy for intractable OCD, comparing deviations in the native scans to those in standard space. MNI measurements were significantly larger than native measurements across several structures in both coronal and axial slices, and we found that MNI transformation increases the size of many subcortical structures in a significant and proportional way for both females and males. These findings urge caution when using MNI as a reference space, as well as a stronger consideration of population-specific brain templates when examining connectivity-based networks.

Study on geometry and morphology of proximal humerus in Northern Chinese population based on 3-D CT

BackgroundThis study investigated the characteristics of humeral geometric and morphological parameters in northern Chinese population by three-dimensional measurements, and compared whether there were differences in humeral morphology among populations from different geographical regions.MethodsComputed tomography scans of 80 humerus were obtained, reconstructed and measured. Differences in humeral morphological parameters between genders and sides were compared. Correlation analysis was used to explore possible correlations among the parameters. The differences in humeral geometric morphometric parameters between Western and East Asian populations were compared according to pool results of present and previous studies.ResultsThe average (and standard deviation) of humeral head radius curvature, arc angle, diameter, and thickness was 151.79 ± 6.69°, 23.36 ± 2.08 mm, 44.83 ± 3.92 mm and 17.55 ± 1.84 mm in coronal humeral head plane, and 152.05 ± 8.82°, 21.81 ± 1.88 mm, 41.77 ± 3.44 mm and 16.52 ± 1.92 mm in transversal humeral head plane. The average of the humeral head medial offset and posterior offset was 7.34 ± 2.47 mm and 0.08 ± 1.72 mm. Humeral head inclination angle, arc angle and radius curvature of humeral neck-shaft averaged 137.69 ± 4.92°, 34.7 ± 5.29° and 55.76 ± 13.43 mm. Superior, inferior, anterior, posterior concave angle of humeral anatomical neck averaged 150.41 ± 10.91°, 146.55 ± 10.12°, 146.43 ± 13.53° and 149.33 ± 14.07°. The average of height of the greater tuberosity, height of the lesser tuberosity, depth, concave angle and volume of the intertubercular groove was 14.19 ± 1.7 mm, 8.9 ± 1.54 mm, 0.92 ± 0.31 mm3, 31.28 ± 9.61 mm, 4.98 ± 1.19 mm and 89.35 ± 17.62°. The upper angle of the greater tuberosity averaged 161.04 ± 7.84°, the upper angle of the greater tuberosity was 165.94 ± 3.6°. Differences in parameters of proximal humerus between genders and sides were found. There was no correlation between parameters of proximal humerus and age. Correlations were found among humeral morphological parameters. East Asian populations differed in proximal humeral morphology from Western populations.ConclusionsThis study will provide references for diagnosing and classifying shoulder disease, designing prosthesis and instrument, enhancing surgical precision and guiding patient recovery.

Medical errors and patient safety: Strategies for reducing errors using artificial intelligence

Background: Medical errors remain a significant challenge in healthcare, contributing to adverse patient outcomes, increased costs, and extended hospitalizations. These errors encompass diagnostic inaccuracies, medication mistakes, surgical errors, and communication breakdowns. The global prevalence of medical errors underscores the urgent need for effective strategies to enhance patient safety. Aim: This article explores the role of Artificial Intelligence (AI) in reducing medical errors and improving patient safety. It aims to evaluate how AI technologies can mitigate various types of medical errors, and the challenges associated with their implementation. Methods: The study reviews current literature on AI applications in healthcare, focusing on diagnostic support, medication safety, surgical precision, and patient monitoring. It analyzes the effectiveness of AI-driven systems in reducing errors across different medical disciplines and examines the integration challenges, including ethical and regulatory concerns. Results: AI technologies, including machine learning algorithms and decision support systems, have demonstrated significant potential in enhancing diagnostic accuracy, preventing medication errors, and improving surgical outcomes. AI-driven systems have shown promising results in real-time patient monitoring, early detection of adverse events, and optimizing healthcare management. However, challenges related to data privacy, algorithm transparency, and integration into clinical workflows persist.

Exploring the future of surgical practices

Background: Robotic-Assisted Minimally Invasive Surgery (RAMIS) represents a significant advancement in surgical techniques, leveraging robotic systems to enhance precision, reduce invasiveness, and improve patient outcomes. The da Vinci surgical system has been a leading example, demonstrating the potential of robotic assistance in minimally invasive procedures. Aim: This paper explores the evolution of RAMIS, focusing on technological advancements, integration with Artificial Intelligence (AI), and future directions in surgical robotics. Methods: The study reviews the development and current state of RAMIS technologies, including the historical background, state-of-the-art systems, and emerging innovations. It analyzes data from a range of sources including literature reviews, market reports, and recent research developments. Results: RAMIS systems, particularly the da Vinci surgical system, have achieved widespread adoption due to their advanced features, such as enhanced vision, improved ergonomics, and training programs. Recent advancements include AI integration, new sensor technologies, and enhanced imaging modalities. Despite these improvements, challenges remain in achieving higher levels of autonomy and addressing cost and regulatory issues. Conclusion: RAMIS continues to evolve with significant advancements in AI, haptic feedback, and simulation technologies. Future developments are expected to further enhance surgical precision and outcomes.

Robotics in plastic surgery

In recent years surgical robotic systems which were specifically developed for microsurgery have expanded the application of robotic-assisted surgery to plastic reconstructive surgery. Currently, there are two microsurgical robotic systems available for reconstructive plastic surgery. Both systems feature tremor reduction and motion scaling technologies, which are intended to optimize the surgeon's precision and dexterity. In the Department of Plastic Surgery and Hand Surgery at the University Hospital Zurich, the Symani Surgical System® has already been used for many microsurgical and supermicrosurgical operations, including autologous breast reconstruction, nerve transfer and, in particular, reconstructive lymphatic surgery. Despite special technical challenges, such as alack of haptic feedback, the advantages outweigh the disadvantages for an appropriately trained and skilled microsurgeon, including smaller surgical access incisions for anatomically deep structures and an improvement in surgical precision.

THR Using a 3D Printed Custom Made Acetabulum Component: A Case Report

Introduction: THR is one of the commonly performed adult arthroplasties in the world. Over the past 6 decades, Charnley low friction arthroplasty has evolved in design and concept. One among those recent advances is the use of 3D printing technology in arthroplasties. Purpose of this article is to discuss and share the details of a hip arthroplasty case where a customized 3D printed acetabulum component was used. Case: A 3 year postop case of acetabulum fracture fixation presented with arthritis of hip. CT revealed a periacetabular massive bone loss. After considering all options, decision was made to use a 3D printed acetabulum shell. Discussion: Complex THRs with special instrumentation and augmented implants are frequently seen in revision surgeries and post acetabulum fracture cases. Based on the size and pattern of the defect, IlioIschial cages, Triflange cups, Trabecular metal augments, CupCage constructs, Jumbo cups are some common options at a surgeons disposal while tackling an acetabulum bone loss challenge. A 3D manufactured component can be of aid when the defect is too large. It gives the advantage of being anatomically contoured. It also allows a porous structure for bone ingrowth. Conclusion: Life size models of the pelvis and the component gives an explicit simulation of the surgery, including the component placement and trajectory of the screws. This effective preoperative planning can improve the surgical precision and reduce the complications. Literature on the survival rates and long term complications of such 3d printed acetabulum shells is limited. Studies on the long term outcomes with usage of these implants would be insightful Keywords: 3D Printing, Complex THR, Customised acetabular shell

Surgical anatomy

Abstract Preoperative vascular mapping has been demonstrated to be an excellent adjunct to perforator flap surgery by reducing operative times and enhancing surgical precision. The purpose of this study was to evaluate the benefit of preoperative vascular mapping using magnetic resonance imaging and Doppler ultrasonography to identify the different perforators to the breast and compare it postoperative mapping. Specifically, the intent was to determine whether preoperative knowledge of the various vascular sources to the nipple areolar complex affected the outcome and vitality of the NAC.

The Superficial Fascia System: Anatomical Guideline for Zoning in Liposuction-Assisted Back Contouring.

Dorsal contour deformity presents with different manifestations in each part of the back, such as back rolls, iliac crest deposit, and buffalo hump. However, scant current literature exists on the anatomical basis of dorsal contour deformity. The aim of this study was to better understand the anatomical characteristics of the back, and to propose evidence-based zoning principles for liposuction-assisted back contouring. A total of 12 fresh cadavers were dissected for observation of each hierarchy in the vertical order (skin to deep fascia) and transverse comparison of the superficial fascial system (SFS) in the scapular-infrascapular-lumbar triangle region. Full-dorsum vectorial sections were used for the study of suprascapular fat deposits. The SFS acts as a bridge connecting all levels of the dorsal subcutaneous tissue. Macroscopically, it is denser in the scapular and lumbar triangle regions and looser in the infrascapular region; microscopically, the ultrastructure of the retinaculum cutis consists of loose interlobular fascia and stiff functional fascia. The regional variation pattern of the SFS in the back was consistent with observed back contour deformities in Asian female patients. A better understanding of the topographic anatomy of the back applied to evidenced zoning is the basis for improving surgical precision and avoiding dorsal contour deformity.