Accuracy and Security Analysis of a Cranio-Maxillofacial Plastic Surgery Robot Equipped With Piezosurgery in Genioplasty.

ABSTRACT: This study aims to verify that the craniofacial plastic surgery robot with piezosurgery is more accurate and safer than traditional operations in genioplasty. This study chose data from the Digital Plastic Surgery of Plastic Surgery Hospital in the Chinese Academy of Medical Sciences and Peking Union Medical College. The CT data of the patient's skull were reconstructed in the software, and the authors designed the measurement index. The surgical plan was designed as an ideal scheme (control group). Patients underwent traditional surgery according to the preoperative surgery plan (clinical group). Guided by surgical navigation, the osteotomy was operated on patients' same size plaster model using the surgery robot equipped with a piezosurgery (robot group). At last, the accuracy was calculated by CT data. There was no significant difference between the robotic group and control groups in the postoperative measurement index (P < 0.05). There was no significant difference between the robotic group and the control group ( P > 0.05) in the line of osteotomy, but there was a significant difference between the clinical group and the control group in the line of the osteotomy.

Comparison of an oblique single cut rotation osteotomy with a novel 3D computer-assisted oblique double cut alignment approach.

An oblique double-cut rotation osteotomy (ODCRO) enables correcting a complex bone deformation by aligning, in 3D, the distal, middle and proximal bone segments with a target bone, without intersegmental gaps. We propose virtual preoperative planning of an ODCRO. To minimize a residual translation error, we use an optimization algorithm and optimize towards bone length, alignment in the transverse direction, or a balanced reconstruction. We compare the residual alignment error with an oblique single-cut rotation osteotomy using 15 complex bone deformations. The single-cut approach was not feasible in 5 cases, whereas the ODCRO procedure was feasible in all cases. The residual alignment error was smaller for the ODCRO than for the single-cut approach except for one case. In a subset for length reconstruction, the length error of 7.3-21.3 mm was restored to 0.0 mm in 4 of 5 cases, although at the cost of an increased transverse translation. The proposed method renders planning an ODCRO feasible and helps restoring bone alignment and lengthening better than an oblique single-cut rotation osteotomy. Awareness of the challenges and possibilities in preoperative planning of an ODCRO will be of value for future alignment surgery and for patients.

Preliminary clinical experience of robot-assisted surgery in treatment with genioplasty.

Genioplasty is the main way to treat diseases such as chin asymmetry, dysplasia and overdevelopment, which involve the three-dimensional direction abnormalities of the chin. Since this kind of surgery mainly uses intraoral incisions, the narrow surgical field of intraoral incisions and the surrounding important neurovascular tissues make it easy for complications, to occur during the osteotomy process, which results in greater surgical risks. The first craniofacial-plastic surgical robot (CPSR-I) system is developed to complete the precise positioning and improve the surgeon's force perception ability. The Kalman filtering method is adopted to reduce the interference of sensor signal noise. An adaptive fuzzy control system, which has strong robustness and adaptability to the environment, is designed to improve the stability of robot-assisted surgical operations. To solve the problem of the depth perception, we propose an automatic bone drilling control strategy that combines position and force conditions to ensure that the robot can automatically stop when the bone is penetrated. On the basis of model surgery and animal experiments, preliminary experiments were carried out clinically. Based on the early results of 6 patients, the robot-assisted approach appears to be a safe and effective strategy for genioplasty.

Powered Rhinoplasty: A Simple Step-by-Step Approach.

SUMMARY: Reduction of a nasal hump and nasal base narrowing are very common steps during a primary rhinoplasty procedure. The greatest difficulty is to obtain stable fracture lines, a natural appearance, beautiful dorsal aesthetic lines, and the absence of palpable or visible irregularities, especially in the long term. The surgeon strives for a reproducible technique, which seems to be more feasible with mechanical osteotomies (powered or piezoelectric) than with traditional manual osteotomies. The aim of this article is to describe powered osteotomy in a step-by-step fashion to provide a clear guideline for rhinoplasty surgeons.

A Comparison of Three Different Positioning Techniques on Surgical Corrections and Postoperative Alignment in Cervical Spinal Deformity (CD) Surgery.

STUDY DESIGN: Retrospective review of a prospective multicenter cervical deformity database. OBJECTIVE: To examine the differences in sagittal alignment correction between three positioning methods in cervical spinal deformity surgery (CD). SUMMARY OF BACKGROUND DATA: Surgical correction for CD is technically demanding and various techniques are utilized to achieve sagittal alignment objectives. The effect of different patient positioning techniques on sagittal alignment correction following CD remains unknown. METHODS: Patients with sagittal deformity who underwent a posterior approach (with and without anterior approach) with an upper instrumented vertebra of C6 or above. Patients with Grade 5, 6, or 7 osteotomies were excluded. Positioning groups were Mayfield skull clamp, bivector traction, and halo ring. Preoperative lower surgical sagittal curve (C2-C7), C2-C7 sagittal vertical axis (cSVA), cervical scoliosis, T1 slope minus cervical lordosis (TS-CL), T1 slope (T1S), chin-brow vertebral angle (CBVA), C2-T3 curve, and C2-T3 SVA was assessed and compared with postoperative radiographs. Segmental changes were analyzed using the Fergusson method. RESULTS: Eighty patients (58% female) with a mean age of 60.6 ±â€Š10.5 years (range, 31-83) were included. The mean postoperative C2-C7 lordosis was 7.8°â€Š±â€Š14 and C2-C7 SVA was 34.1 mm ±â€Š15. There were overall significant changes in cervical alignment across the entire cohort, with improvements in T1 slope (P < 0.001), C2-C7 (P < 0.001), TS-CL (P < 0.001), and cSVA (P = 0.006). There were no differences postoperatively of any radiographic parameter between positioning groups (P > 0.05). The majority of segmental lordotic correction was achieved at C4-5-6 (mean 6.9°â€Š±â€Š11). Additionally, patients who had bivector traction applied had had significantly more segmental correction at C7-T1-T2 compared with Mayfield and halo traction (4.2° vs. 0.3° vs. -1.7° respectively, P < 0.027). CONCLUSION: Postoperative cervical sagittal correction or alignment was not affected by patient position. The majority of segmental correction occurred at C4-5-6 across all positioning methods, while bivector traction had the largest corrective ability at the cervicothoracic junction.Level of Evidence: 4.

New perspectives on surgical accuracy analysis of image-guided bone tumour resection surgery.

PURPOSE: Image-guided bone tumour resection surgery has been proved in previous literatures to be more accurate than those conventional freehand ones (p < 0.001). However, in this kind of surgery, there are still many procedures depending on manual operations, which will inevitably introduce surgical errors into the surgery. In particular, the negative surgical errors (i.e., errors toward tumour) would increase the risk of tumor recurrence and metastasis. Thus, the first purpose of this study was to evaluate whether the negative surgical errors of image-guided bone tumour resection surgery were statistically significantly great, the second purpose is to evaluate whether the negative surgical errors of image-guided long-bone tumour resection surgery were statistically equivalent to those of pelvis surgery, and the last purpose is to recommend a solution for suppressing these errors when using a navigation system. METHODS: Negative surgical errors of 24 osteotomies in ten pelvis tumour resection operations and 16 osteotomies in ten long-bone surgeries under the image guidance of a navigation system were statistically evaluated and compared with - 2.0 mm. The equivalence of negative surgical errors of pelvis group and those of long-bone group was statistically tested. To suppress these negative surgical errors when using a navigation system, we recommend, based on the obtained statistics, to increase the margins between cut planes and tumour boundary during pre-operatively planning cut planes, by adding an extra margin with the empirical safe margin according to the absolute lower bound of 95% CI of negative surgical errors. RESULTS: Negative surgical errors of the pelvis group and the long-bone group were both significantly less than - 2.0 mm (p < 0.001), but not statistically equivalent (Rg > 1 mm). 95% CI of negative surgical errors were from - 3.95 to - 3.27 mm for the pelvis group, and from - 2.69 to - 2.34 mm for the long-bone group. So, the extra margin added for image-guided pelvis tumour resection surgery should be set as 3.95 mm, and the extra margin added for image-guided long-bone surgery should be set as 2.69 mm. CONCLUSION: The negative surgical errors of image-guided bone resection surgery were statistically significantly less than - 2.0 mm (p < 0.001), thus these errors cannot be safely ignored. Moreover, the negative surgical errors of the pelvis group were not equivalent to those of the long-bone group (Rg > 1.0 mm), thus the solution for image-guided pelvis tumour resection surgery and that for image-guided long-bone tumour resection surgery should be separately determined. In order to suppress these negative surgical errors when using a navigation system, we recommend to add extra 3.95 mm margin with the empirical safe margin for image-guided pelvis tumour resection surgery and to add extra 2.69 mm margin for image-guided long-bone tumour resection surgery during pre-operatively planning cut planes.

Comparison of 2 Surgeries in Correction of Severe Kyphotic Deformity Caused by Ankylosing Spondylitis: Vertebral Column Decancellation and Pedicle Subtraction Osteotomy.

OBJECTIVE: To compare the treatment results between 1-level vertebral column decancellation (VCD) and pedicle subtraction osteotomy (PSO) for correcting severe kyphotic deformity in ankylosing spondylitis (AS). VCD and PSO have been used to correct AS-related kyphotic deformity, but the differences on correcting results between VCD and PSO are not clear. METHODS: Between 2013 and 2015, 57 patients underwent 1-level spinal osteotomy (VCD: n = 30; PSO: n = 27) for correcting kyphotic deformity. Sagittal parameters, fusion results, surgical information, and clinical outcomes were documented and compared. All data were obtained before and 1 week after surgery, 6 months after surgery, and at final follow-up (at least 2 years). RESULTS: VCD provided significantly greater osteotomy angle (50.8° ± 9.7°) than PSO (38.5° ± 6.1°). In the VCD group, the change of the anterior column was 5.0 ± 1.3 mm, which was larger than the PSO group. The middle column was shortened by 9.9 ± 2.0 mm and 19.1 ± 3.3 mm in the VCD group and PSO group, respectively. There was no significant difference in operating time and blood loss between the 2 groups. All cases had solid fusion. Between the 2 groups, Scoliosis Research Society Outcomes Instrument-22 scores were similar at the final follow-up. No major acute complications occurred in both groups. CONCLUSIONS: VCD is a safe and effective method in treating rigid kyphotic deformity secondary to AS. VCD provides a larger correction angle in one segment and preserves more height of osteotomized vertebrae than PSO.

Rationale and Options for Choosing an Optimal Closure Technique for Primary Midsagittal Osteochondrotomy of the Sternum. Part 3: Technical Decision Making Based on the Practice of Patient- Appropriate Medicine.

The topographic anatomy of the sternum is similar in a healthy population. However, in a clinical subset of patients with comorbidities such as diabetes mellitus, chronic obstructive pulmonary disease, high body mass index, chronic renal disease, or age-related osteoporosis, there are significant changes in the normal physiology that may influence overall patient outcome following trans-sternal intrathoracic surgery. These changes can create technical difficulties in reconstructing the bisected sternum and adversely affect the biomechanics of the thoracic wall, forcing difficult surgical choices with regard to implant options and increasing the cost of an otherwise routine cardiac surgery. A thorough preoperative surgical and technical planning is essential to avert perioperative complications such as failure of wound healing, non-union of the sternum, and life-threatening mediastinitis. Patient expectations need to be explored and the patients should be well informed so that they can make knowledgeable choices regarding their illness and surgical interventions. They should also be given a probable prognosis to provide psychological support. Within the realm of clinical methodology, the concept of patient-appropriate medicine is introduced to direct attending team to become aware of overall health of its patient. The inclusion of a clinical biomechanical engineer as a surgical team member is recommended to perform patient-specific finite element analysis to select an optimal implant to fix the sternum. To help assess the overall benefit-risk profile objectively, an absolute therapeutic index has been proposed.

Standardization of torsional CT measurements of the lower limbs with threshold values for corrective osteotomy.

INTRODUCTION: Re-establishing anatomic rotational alignment of shaft fractures of the lower extremities remains challenging. Clinical evaluation in combination with radiological measurements is important in pre- and post-surgical assessment. Based on computed tomography (CT), a range of reference values for femoral torsion (FT) and tibial torsion (TT) have historically been reported, which require standardization to optimize the significant intra- and inter-observer variability. The aims of this study were (re-)evaluation of the reference FT and TT angles, determination of the normal intra-individual side-to-side torsional differences to aid the surgical decision-making process for reoperation, and development of a novel 3D measurement method for FT. MATERIALS AND METHODS: In this retrospective study, we included 55 patients, without any known torsional deformities of the lower extremities. Two radiologists, independently, measured the rotational profile of the femora using the Hernandez and Weiner CT methods for FT, and the tibiae using the bimalleolar method for TT. The intra-individual side-to-side difference in paired femora and paired tibiae was determined. A 3D technique for FT assessment using InSpace® was designed. RESULTS: FT and TT demographic values were lower than previously reported, with mean FT values of 5.1°-8.8° and mean TT values of 25.5°-27.7°. Maximal side-to-side differences were 12°-13° for FT and 12° for TT. The Weiner method for FT was less variable than the Hernandez method. The new 3D method was equivocal to the conventional CT measurements. CONCLUSION: The results from this study showed that the maximal side-to-side tolerance in asymptomatic normal adult lower extremities is 12°-13° for FT and 12° for TT, which could be a useful threshold for surgeons as indication for revision surgery (e.g., derotational osteotomy). We developed a new 3D CT method for FT measurement which is similar to 2D and could be used in the future for virtual 3D planning.

Accuracy of Freehand Pedicle Screw Placement in Surgical Correction of Thoracolumbar Kyphosis Secondary to Ankylosing Spondylitis: A Computed Tomography Investigation of 2314 Consecutive Screws.

OBJECTIVE: To evaluate the accuracy and safety of freehand pedicle screw placement in surgical correction for thoracolumbar kyphosis caused by ankylosing spondylitis (AS). METHODS: We retrospectively reviewed 266 consecutive patients with AS who underwent osteotomy for kyphosis correction with freehand screw insertion from January 1998 to April 2015 at our institution. A total of 2314 pedicle screws in 158 patients with AS with postoperative computed tomography scans were included in the study. Postoperative computed tomography was performed to classify accuracy of screws, using the established Gertbein classification (grade 0: no perforation, grade 1: perforation <2 mm, grade 2: perforation between 2 and 4 mm, and grade 3: perforation >4 mm). Patients were divided into 2 groups according to coronal Cobb angle: group A (n = 21, Cobb angle ≥10°), group B (n = 137, Cobb angle <10°). RESULTS: Among the 2314 pedicle screws, 2168 pedicle screw placements were categorized as grade 0, 71 were grade 1, 51 were grade 2, and 24 were grade 3. Breaches occurred more frequently in L1-S1 than the thoracic spine (7.1% and 5.4%, respectively). T5 (25.0%) and S1 (17.7%) experienced the greatest breach rate, whereas T8, L1, and L3 had the lowest breach rate. The breach rate of group A was greater than that of group B (7.9% vs. 6.1%). None of the breaches resulted in either neurologic deficits or vascular complications. CONCLUSIONS: Freehand pedicle screw placement can be performed safely with acceptable breach rate in patients with AS and thoracolumbar kyphosis.

Osteotomía del peroné, nueva técnica quirúrgica en el genu varo doloroso. Proceder y presentación de dos casos / Fibular osteotomy, new surgical technique in the painful genu varum: procedure and two-case presentation

La artrosis de rodilla puede llegar a ser una patología muy invalidante por los síntomas que produce, caracterizados por dolor, inseguridad y pérdida funcional. Es una patología degenerativa cuya prevalencia ha ido en aumento en las últimas décadas. Está muy ligada al aumento de las expectativas de vida de la población, fenómeno que ocurre en países del primer mundo con un alto nivel de salud y que ocurre igualmente en nuestro país dado el desarrollo de nuestro sistema de salud. Existen múltiples técnicas quirúrgicas para corregir la deformidad y aliviar el dolor; van desde osteotomías correctoras hasta las artroplastias, todas encaminadas al alivio del dolor en primer lugar y a corregir las deformidades, pero las últimas conllevan mayor tiempo de rehabilitación y son más costosas. Este trabajo va encaminado a la presentación de dos pacientes operados con la nueva técnica del Dr. Ying Ze Zhang, del Departamento de Cirugía Ortopédica del Tercer Hospital de la Universidad Médica de Hebei en Shijiazhuang, China, con la cual, a través de una osteotomía, se descomprime el compartimento interno y se quita tensión ósea en el externo por la resección peronea. Sus objetivos son actuar sobre el dolor, mejorar la función y la marcha como beneficios de este proceder de mínima acción sobre las partes articulares y lograr la rápida incorporación del paciente a su vida social; esto es tema para la obtención del doctorado por parte del autor principal del presente trabajo (AU).

Knee osteoarthritis could be a very disabling disease due to the symptoms it produces, characterized by pain, insecurity and functional loss. It is a degenerative disease which prevalence has increased in the last decades tightly related to the increment of the population's life expectancy, phenomenon occurring in the developed countries with a high life level and also occurring in our country because of the development of our health system. There are several surgical techniques to correct deformation and to relieve pain. They go through correcting osteotomies to arthroplasties, all of them aimed, firstly to pain relieving and also to correcting deformations. The last ones need more rehabilitation time and are more expensive. This work is devoted to presenting two patients operated with the new technique of Dr. Yin-Ze Zhang, from the Department of Orthopedic Surgery of the Third Hospital of the Medical University of Hebei, in Shijiazhuang, China, with which, through an osteotomy, the internal compartment is decompressed and the bone tension in the external one is finished due to the peroneal excision. Its aims are acting upon the pain, improving function and gait as a benefit of this minimal action procedure on the articular parts and achieving the faster incorporation of the patient to his social life; this is the theme the main author of this article is going to develop for obtaining the doctorate in sciences (AU).

Results of the 2015 Scoliosis Research Society Survey on Single Versus Dual Attending Surgeon Approach for Adult Spinal Deformity Surgery.

STUDY DESIGN: An electronic survey administered to Scoliosis Research Society (SRS) membership. OBJECTIVE: To characterize surgeon practices and views regarding the use of two attending surgeons for adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND DATA: The use of two experienced attending surgeons can decrease the operative time, estimated blood loss, and perioperative complication rates. However, the current practice patterns for the use of two attending surgeons remains unknown. METHODS: An electronic, 27-question survey regarding single/dual attending surgeons was administered to the SRS membership. Determinants included: surgeon/practice demographics, assistant type/level of training, and questions regarding use of two attending surgeons. Overall reporting and comparisons between groups were made: US versus international, academic versus private practice, and experience <15 years versus >15 years. RESULTS: A total of 199 surgeons responded from 27 different countries. Overall and between the groups, the respondents significantly reported believing that two attending spine surgeons improves safety, decreases complications, and improves outcomes (P < 0.01). Approximately, 67.3% reported using a second attending ≤25% of the time (33.2% do not), and 24.1% use one ≥51% of the time (similar between groups); 51.1% that have a second attending feel it's limited by reimbursement and access concerns and 71.9% have difficulty getting the second attending reimbursed. 72.3% use a second attending for ALL of the following reasons (no difference between groups): "it's safer/reduces complications," "it decreases operative time," "it decreases blood loss," "it results in improved outcomes," "it's less work and stress for me." If reimbursement was equal/assured for a second attending, 67.5% would use one "more often" or "always." CONCLUSION: The respondents feel that having a second attending surgeon improves patient care, however most do not use one often. Reasons include reimbursement/access concerns and the majority would use one if reimbursement was equal and assured. Based on the current literature and these results, there is a need for working with third party payers to improve dual surgeon reimbursement rates in complex cases. LEVEL OF EVIDENCE: 5.

Owner assessment of the outcome of tibial plateau levelling osteotomy without meniscal evaluation for treatment of naturally occurring cranial cruciate ligament rupture: 130 cases (2009 to 2013).

OBJECTIVE: To evaluate long-term surgical outcome and chronic pain in dogs suffering from naturally occurring cranial cruciate ligament rupture treated by tibial plateau levelling osteotomy without meniscal evaluation. MATERIALS AND METHODS: In this retrospective clinical study, data from surgical records of dogs with cranial cruciate ligament rupture that underwent tibial plateau levelling osteotomy without meniscal evaluation between August 2009 and November 2013 were reviewed. An owner questionnaire was used to evaluate the long-term outcome and the prevalence of chronic pain. RESULTS: 107 dogs were included in this study. The long-term follow-up ranged from 1 to 4·5 years (mean 2·5 years). Four dogs developed acute lameness 4 to 21 months after surgery after having shown improvement. Dog behavior was assessed to be normal in 93% of cases and the level of activity was estimated to be normal for 88% of cases. Persistent lameness was reported after surgery in 6% of dogs and might have resulted from undiagnosed meniscal lesions. CLINICAL SIGNIFICANCE: Considering the low incidence of persistent lameness after surgery and the limits of diagnosis and treatment, the need for routine meniscal examination during tibial plateau levelling osteotomy is questionable.

Unicompartmental knee arthroplasty, is it superior to high tibial osteotomy in treating unicompartmental osteoarthritis? A meta-analysis and systemic review.

BACKGROUND: Debate remains whether high tibial osteotomy (HTO) or unicompartmental knee arthroplasty (UKA) is more beneficial for the treatment of unicompartmental knee osteoarthritis. The purpose of this study was to compare the functional results, knee scores, activity levels, and complications between the two procedures. METHODS: We performed a systematic review of published literature from August 1982 through January 2017. Fifteen papers reporting three prospective randomized trials were subjected to a meta-analysis. RESULTS: No significant difference between the two groups was noted with respect to free walking (velocity), knee score, deterioration of the contralateral or patellofemoral knee, or revision rate and total knee arthroplasty. However, UKA produced better outcomes compared to HTO in terms of the functional results, pain assessment, and complications, although patients who underwent HTO tended to have slightly better range of motion. CONCLUSIONS: Valgus HTO provides better physical activity for younger patients whereas UKA is more suitable for older patients due to shorter rehabilitation time and faster functional recovery. Although UKA patients tended to have improved overall long-term outcomes, which may be due to accurate indications and patient selection, both treatment options yielded pleasing results. Therefore, we are unable to conclude that either method is superior.

Surgical and Radiographic Outcomes After Pedicle Subtraction Osteotomy According to Surgeon's Experience.

STUDY DESIGN: Retrospective case series. OBJECTIVE: The aim of this study was to evaluate and compare the surgical, radiographic, and clinical outcomes of pedicle subtraction osteotomy (PSO) according to surgeon's experience. SUMMARY OF BACKGROUND DATA: Although PSO has been widely used to correct spinal deformities, it still remains technically demanding procedure with high complications. METHODS: Comparative analysis of 40 consecutive patients treated with lumbar PSOs was performed. According to time period, the former and latter 20 patients were divided into group 1 and group 2, respectively. Patients' demographic data, operative, radiographic/clinical outcomes, and complications were compared between the groups. RESULTS: Baseline characteristics and preoperative radiographic parameters were not different between the groups. Significant reductions of operative time (569.6 vs. 392.0 minutes, P = 0.000), surgical bleeding (1777.5 vs. 949.5 mL, P = 0.002), and transfused volume of red blood cell (1232.6 vs. 864.1 mL, P = 0.041) in group 2 were observed. Postoperative sagittal vertical axis was significantly different between the groups (40.1 and -3.6 mm, groups 1 and 2, respectively, P = 0.008), and the difference was sustained to the ultimate follow-up (59.4 vs. 13.2 mm, P = 0.003). There was a difference regarding the amount of curve correction by PSO, which was significantly greater in group 2 (25.7° vs. 35.8°, P = 0.023). Intraoperative complications (7 vs. 1, P = 0.019) were significantly lower in group 2. Total complications (20 vs. 10, P = 0.070), postoperative transient neurologic deficit (2 vs. 1), and revision surgery (4 vs. 3) were also lower in group 2, without statistical significance. The amount of the improvement of SRS-22 score was not different between the groups (P = 0.395). CONCLUSION: PSO may be performed in patients with fixed sagittal imbalance with an acceptable rate of complications after about 20 cases. With acquisition of surgical experiences, surgeons could perform PSO more effectively and safely.

[Treatment of Osteochondral Lesions in the Ankle: A Guideline from the Group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Traumatology (DGOU)]. / Behandlung osteochondraler Läsionen des Sprunggelenks: Empfehlungen der Arbeitsgemeinschaft Klinische Geweberegeneration der DGOU.

Background: Osteochondral lesions (OCL) of the ankle are a common cause of ankle pain. Although the precise pathophysiology has not been fully elucidated, it can be assumed that a variety of factors are responsible, mainly including traumatic events such as ankle sprains. Advances in arthroscopy and imaging techniques, in particular magnetic resonance imaging (MRI), have improved the possibilities for the diagnosis of OCLs of the ankle. Moreover, these technologies aim at developing new classification systems and modern treatment strategies. Material and Methods: This article is a review of the literature. Recommendations of the group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Traumatology (DGOU) for the treatment of OCLs of the ankle are presented. The review gives a concise overview on the results of clinical studies and discusses advantages and disadvantages of different treatment strategies. Results: Non-operative treatment shows good results for selected indications in children and adolescents, especially in early stages of osteochondritis dissecans (OCD). However, surgical treatment is usually indicated in OCLs in adolescents and adults, depending on the size and location of the lesion. Various arthroscopic and open procedures are frequently employed, including reattachment of the fragment, local debridement of the lesion with fragment removal and curettage of the lesion, bone marrow-stimulation by microfracture or microdrilling (antegrade or retrograde), and autologous matrix-induced chondrogenesis (AMIC®) - with or without reconstruction of a subchondral bone defect or cyst by autologous cancellous bone grafting. Isolated subchondral cysts with an intact cartilage surface can be treated by retrograde drilling and possibly additional retrograde bone grafting. For larger defects or as salvage procedure, osteochondral cylinder transplantation (OATS® or Mosaicplasty®) or matrix-induced autologous chondrocyte transplantation (MACT) are recommended. Transplantation of so-called (osteochondral) mega grafts, such as autologous bone grafts or allografts, are used for very large osteochondral defects that cannot be reconstructed otherwise. Implantation of the so-called "small metal implants" - such as HemiCAP Talus® - is reserved for selected cases after failed primary reconstruction. Corrective osteotomies are indicated in accompanying axial malalignments. Conclusions: There are several different treatment strategies for OCLs, but clinical studies are rare and evidence is limited. Therefore, interventional studies, e.g. randomised controlled trials (RCTs), but also observational studies, e.g. based on data of the Cartilage Registry of the German Society of Orthopaedics and Traumatology (www.knorpelregister-dgou.de), are needed and are recommended by the authors.

[Intraoperative quality management modalities in head and neck surgery]. / Intraoperative Modalitäten zur Qualitätssicherung in der Kopf­Hals­Chirurgie.

Immediate intraoperative control via suitable imaging techniques is necessary to achieve the best possible surgical outcome. Intraoperative imaging increases patient safety, offers the surgeon direct support in challenging anatomic regions, and affords the possibility of direct correction with a reduced rate of corrective surgery. The procedures are based on cone beam computed tomography (CBCT), endoscopy, or navigation-assisted surgery. This article describes available intraoperative quality management modalities for fracture management and tumor treatment in the field of head and neck surgery.

Inpatient morbidity and mortality after adult spinal deformity surgery in teaching versus nonteaching hospitals.

OBJECTIVE The goal of this study was to compare inpatient morbidity and mortality after adult spinal deformity (ASD) surgery in teaching versus nonteaching hospitals in the US. METHODS The Nationwide Inpatient Sample was used to identify surgical patients with ASD between 2002 and 2011. Only patients > 21 years old and elective cases were included. Patient characteristics, inpatient morbidity, and inpatient mortality were compared between teaching and nonteaching hospitals. A multivariable logistic regression analysis was performed to examine the effect of hospital teaching status on surgical outcomes. RESULTS A total of 7603 patients were identified, with 61.2% (n = 4650) in the teaching hospital group and 38.8% (n = 2953) in the nonteaching hospital group. The proportion of patients undergoing revision procedures was significantly different between groups (5.2% in teaching hospitals vs 3.9% in nonteaching hospitals, p = 0.008). Likewise, complex procedures (defined as fusion of 8 or more segments and/or osteotomy) were more common in teaching hospitals (27.3% vs 21.7%, p < 0.001). Crude overall complication rates were similar in teaching hospitals (47.9%) compared with nonteaching hospitals (49.8%, p = 0.114). After controlling for patient characteristics, case complexity, and revision status, patients treated at teaching hospitals were significantly less likely to develop a complication when compared with patients treated at a nonteaching hospital (OR 0.89; 95% CI 0.82-0.98). The mortality rate was 0.4% in teaching hospitals and < 0.4% in nonteaching hospitals (p = 0.210). CONCLUSIONS Patients who undergo surgery for ASD at a teaching hospital may have significantly lower odds of complication development compared with patients treated at a nonteaching hospital.

Surgical accuracy in high tibial osteotomy: coronal equivalence of computer navigation and gap measurement.

PURPOSE: Medial opening wedge high tibial osteotomy (MOW HTO) is now a successful operation with a range of indications, requiring an individualised approach to the choice of intended correction. This manuscript introduces the concept of surgical accuracy as the absolute deviation of the achieved correction from the intended correction, where small values represent greater accuracy. Surgical accuracy is compared in a randomised controlled trial (RCT) between gap measurement and computer navigation groups. METHODS: This was a prospective RCT conducted over 3 years of 120 consecutive patients with varus malalignment and medial compartment osteoarthritis, who underwent MOW HTO. All procedures were planned with digital software. Patients were randomly assigned into gap measurement or computer navigation groups. Coronal plane alignment was judged using the mechanical tibiofemoral angle (mTFA), before and after surgery. Absolute (positive) values were calculated for surgical accuracy in each individual case. RESULTS: There was no significant difference in the mean intended correction between groups. The achieved mTFA revealed a small under-correction in both groups. This was attributed to a failure to account for saw blade thickness (gap measurement) and over-compensation for weight bearing (computer navigation). Surgical accuracy was 1.7° ± 1.2° (gap measurement) compared to 2.1° ± 1.4° (computer navigation) without statistical significance. The difference in tibial slope increases of 2.7° ± 3.9° (gap measurement) and 2.1° ± 3.9° (computer navigation) had statistical significance (P < 0.001) but magnitude (0.6°) without clinical relevance. CONCLUSION: Surgical accuracy as described here is a new way to judge achieved alignment following knee osteotomy for individual cases. This work is clinically relevant because coronal surgical accuracy was not superior in either group. Therefore, the increased expense and surgical time associated with navigated MOW HTO is not supported, because meticulously conducted gap measurement yields equivalent surgical accuracy. LEVEL OF EVIDENCE: I.

The influence of patient age and bone mineral density on osteotomy fixation stability after hallux valgus surgery: A biomechanical study.

BACKGROUND: Oblique osteotomies of the first metatarsal are common surgical treatments for moderate to severe hallux valgus deformity. Osteotomy fixation integrity is important to minimize interfragment motion and maintain correction during healing, and our clinical observations suggest that patient age and bone quality affect fixation stability and ultimately the clinical outcome. Accordingly, this study correlated these patient factors with key mechanical measures of osteotomy angulation resistance in a cadaver hallux valgus correction model. METHODS: Standard Ludloff osteotomies were created in 31 fresh-frozen first metatarsals and fixed with two cannulated, dual-pitch headless screws. Each specimen underwent 1000 plantar-to-dorsal bending loads while monitoring bending stiffness and distal fragment dorsal angulation. Donor age and bone mineral density were then correlated with each mechanical measure at selected cycling increments. FINDINGS: We found significant positive correlation between bone mineral density and osteotomy fixation stiffness for all evaluated load cycles. Moderate negative correlation between bone density and angulation was identified, significant for load cycle 500. There was a weak, nonsignificant negative correlation between donor age and osteotomy bending stiffness, with r ranging from -0.134 to -0.243 between the first and 1000th loads. Little correlation was demonstrable between age and angulation. INTERPRETATION: Because low bone density correlates with decreased osteotomy site stiffness and increased angulation under load, patient compliance and protected weight bearing in the early postoperative phase are particularly important if bone mineral density is exceptionally low. Correspondingly, patients with especially high bone mineral density may be considered candidates for earlier weight bearing and active physical therapy.