Kristian Kniha

• DDS; Priv. Doz.
• RWTH Aachen University

Introduction The aim of this study was to evaluate perfusion parameters and clinical features of healthy implants and implants affected by peri‐implant disease in patients who had undergone microvascular jaw reconstruction. Methods A total of 25 patients with 92 implants placed in microvascular transplants were included. Of these, 68 implants show...

Objectives Follow-up results of modern zirconia implants inserted in fibula free and deep circumflex iliac artery (DCIA) flaps with fixed dentures are scarce. This study aimed to evaluate crestal bone changes and the survival rate of zirconia implants for up to 1.5 years of prospective follow-up. Materials and methods Ten patients with six fibula...

Objectives: The topical application of hyaluronic acid after injury may accelerate the wound healing process. We aimed to retrospectively investigate whether the topical application of hyaluronic acid on standardized wounds after split-thickness skin graft removal on the thigh would accelerate wound healing and improve scarring outcomes. Additional...

Background: Tumorous diseases of the jaw demand effective treatments, often involving continuity resection of the jaw. Reconstruction via microvascular bone flaps, like deep circumflex iliac artery flaps (DCIA), is standard. Computer aided planning (CAD) enhances accuracy in reconstruction using patient-specific CT images to create three-dimensiona...

Objectives The aim of this study was to evaluate the peri-implant perfusion, such as oxygen saturation, the relative amount of hemoglobin, and blood flow, in implants placed in pristine bone and avascular and microvascular grafts using a non-invasive measurement method. Materials and methods A total of 58 patients with 241 implants were included....

Objectives The aim of this study was to evaluate whether thermal implant removal of osseointegrated implants is possible using a diode laser with an specific temperature–time interval. Materials and methods First, tooth extraction of the first three premolars was performed in the maxilla and mandible on both sides of 10 pig. After 3 months, implan...

Introduction: Amelogenesis imperfecta (AI) is a genetically determined, non-syndromic enamel dysplasia that may manifest as hypoplasia, hypomaturation, or hypocalcification and can commonly be classified into four primary groups. In this retrospective analysis, specific orofacial characteristics are described and associated with each of the AI type...

Purpose The deep circumflex iliac crest flap (DCIA) is used for the reconstruction of the jaw. For fitting of the transplant by computer-aided planning (CAD), a computerized tomography (CT) of the jaw and the pelvis is necessary. Ready-made cutting guides save a pelvic CT and healthcare resources while maintaining the advantages of the CAD planning...

Objectives: This prospective follow-up study aimed to evaluate the stability values of tapered titanium implants inserted into maxilla following ridge augmentation with free iliac bone graft and crestal bone changes up to three years of follow-up. Material and Methods: A total of seven patients with 34 tapered titanium implants in the maxilla with...

Abstract Background: The high volume of the fasciomyocutaneous anterolateral thigh flaps (ALT) is suitable for the reconstruction of pronounced soft tissue defects. At the same time, harvesting ALT results in a drastic change in thigh shape. Here, we present an optical three-dimensional imaging method for thigh comparison, which can be an objectiv...

Objectives: The present study aims to assess the impact of bilateral and high oblique sagittal split osteotomy (BSSO/HSSO), as well as displacement distances and directions on the expected and achievable bone contact area (BCA) and changes in the intercondylar distance (ICD). The primary question addressed is whether mandibular splitting through BS...

Background The aim of this study was to determine the values of different perfusion parameters- such as oxygen saturation, the relative amount of hemoglobin, and blood flow- in healthy subjects compared to patients with gingivitis as a non-invasive measurement method. Methods A total of 114 subjects were enrolled in this study and separated into s...

An increase in rivaroxaban therapies is associated with increased numbers of postoperative bleeding despite the use of hemostatic sponges, which are currently the gold standard treatment. VIVO has shown promising hemostatic results, favorable tissue properties, and ease of application, although it has not yet been used in the oral cavity. The aim o...

Objectives Long-term studies of modern zirconia implants are still insufficient. This prospective 8-year follow-up study investigated one-piece zirconia implants. Materials and methods Patients who had received a one-piece zirconia dental implant (PURE ceramic implant, Institut Straumann GmbH, Basel, Switzerland) were included in this study. Next...

Introduction: The most common chromosomal anomaly is Down syndrome/Trisomy 21, which can be associated with varying degrees of intellectual disability and physical malformation. Specific orofacial characteristics regarding orthodontic treatment options and features are described on the basis of a patient collective from the Witten/Herdecke Universi...

The stability of a microvascular anastomosis is an important prerequisite for successful tissue transfer. Advances in tissue adhesives are potentially opening new avenues for their use in sutureless microsurgical anastomosis, however they have not yet gained clinical acceptance. In this ex vivo study, a novel polyurethane-based adhesive (PA) was us...

Background: This rat study aimed to evaluate the feasibility of temperature thresholds that affect peri‐implant bone cells and morphology and the potential usefulness of thermal necrosis for inducing implant removal for a subsequent in vivo pig study. Methods: On one side, rat tibiae were thermally treated before implant insertion. The contralatera...

Background: The purpose of this study was to evaluate the osseointegration of zirconia and titanium implants in the rat maxilla in specimens under systemic antiresorptive therapy. Materials and methods: After 4 weeks of systematic medication administration (either zoledronic acid or alendronic acid), 54 rats received one zirconia and one titanium i...

The purpose of this rat study was to explore the feasibility of in vivo temperature thresholds affecting bone contact at the implant surface. Based on these data, thermal necrosis should be used for implant removal in the subsequent in vivo study. Rat tibiae of 48 animals at one site were randomly treated with heat or cold before implant insertion....

Background: The evaluation of bone remodelling and dental root resorption can be performed by histological techniques or micro-computed tomography (micro-CT). The present study aimed to evaluate the relationship between these two procedures in the context of cleft repair in a rat model. Methods: The reconstructed maxillae and the orthodontically-m...

Purpose: Based on the excellent long-term data, dental implants made of titanium are considered the international implantological standard for replacing missing teeth. However, ceramic implants made of zirconia (ZrO2) have experi- enced a renaissance in the last 15 years due to constant innovations in materials and products, with material proper- t...

Background The aim of this rat study was to evaluate the feasibility of temperature thresholds that affect peri-implant bone cells and morphology and the potential usefulness of thermal necrosis for inducing implant removal for a subsequent in vivo pig study. Methods On one side, rat tibiae were thermally treated before implant insertion. The cont...

Objective The aim of the present study was to investigate the influence of three grafting materials for cleft repair on ortho- dontic tooth movement in rats. Materials and methods Artificial alveolar clefts were created in 21 Wistar rats and were repaired 4 weeks later using auto- grafts, human xenografts and synthetic bone substitute (beta-tricalc...

Abstract The aim of this study was to compare the soft tissue predicative abilities of two established programs depending on the surgical technique and amount of displacement. On the basis of 50 computed tomography images, 11 orthognathic operations with differences in displacement distances and technique (maxillary advancement, MxA; maxillary impa...

Primary stability in low-density bone is crucial for the long-term success of implants. Tapered implants have shown particularly favourable properties under such conditions. The aim of this study was to compare the primary stability of tapered titanium and novel cylindrical zirconia dental implant systems in low-density bone. Fifty implants (25 tap...

Aim This study evaluated artificial bone models against a human bone substitute to assess the primary stability of orthodontic mini-implants (OMIs) at varying implant sites with different morphologies and qualities. Materials and methods A total of 1200 OMI placements of four types were inserted into four artificial bone models of different densit...

Implant outcomes in comparison to a natural tooth in a rat model using systemic alendronate and zoledronate acid drug administrations were assessed. Fifty-four Sprague–Dawley rats were randomly allocated into two experimental groups (drug application of zoledronic acid; 0.04 mg/kg intravenously once a week and alendronic acid; 0.2 mg/kg subcutaneou...

In microsurgical anastomosis, non-synthetic fibrin-based adhesives have predominantly shown superior properties to synthetic cyanoacrylates, but they have hardly any clinical application. This study aimed to investigate the local and systemic effects of synthetically produced biodegradable adhesive VIVO when used in microsurgical anastomosis. VIVO...

Background: The purpose of this follow-up study was to assess the effects of discovery learning and subsequent standardized teaching on students' advanced dental surgical skills. A total of 29 dental students who had no theoretical education on the Rehrmann flap were included in the skills training program. Without prior teaching, the students wer...

Background The aim of the present study was to assess the development of bacterial deposits and morphological parameters around dental zirconia and titanium implants compared with natural teeth during systemic bisphosphonate medication. Materials and methods Fifty-four rats were randomly allocated into one control group and two experimental groups...

Osseointegration is the basis of successful dental implantology and the foundation of cementless arthroplasty and the osseointegrated percutaneous prosthetic system. Osseointegration has been considered irreversible thus far. However, controlled heating or cooling of dental implants could selectively damage the bone at the bone–implant interface, c...

Background The pandemic has challenged educational institutions to catalyze digitalization and rapidly develop online teaching formats. The aim of the study was to evaluate the teaching offered for oral and maxillofacial surgery at our university during the pandemic and to investigate the students’ perceptions of the current situation. Methods A 3...

Background: The pandemic has challenged educational institutions to catalyze digitalization and rapidly develop online teaching formats. The aim of the study was to evaluate the teaching offer for oral and maxillofacial surgery at our university during the pandemic and to investigate the students’ perceptions of the current situation. Methods: A 38...

Background In dentistry, the reporting of panoramic radiographs is particularly challenging, as many structures are depicted in one image and pathologies need to be identified completely. To enhance the learning process for these interpretations, the advantages of the increasingly popular education method of mobile learning could be used. Therefore...

Background: Harvesting vascularized bone grafts with computer-assisted surgery represents the gold standard for mandibular reconstruction. However, current augmented reality (AR) approaches are limited to invasive marker fixation. This trial compared a markerless AR-guided real-time navigation with virtually planned and 3D printed cutting guides f...

Background and objectives: In oral and maxillofacial operations, the iliac crest is a commonly used donor site from which to harvest bone for augmentation prior to dental implantation or for reconstruction of jaw defects caused by trauma or pathological lesions. In an aging society, the proportion of elderly patients undergoing iliac crest bone gra...

In addition to full-guided planning before surgery, digital processes can also be used directly after implant placement. In this approach, the implant position is recorded directly after the insertion of the implant body via scan bodies. Afterward, the digital data can be sent to the referring colleagues for immediate restoration, for example, to o...

Loading protocols can be combined with simultaneous extraction and immediate implant placement. Some examples are immediate loading (with occlusion) or immediate restoration (without occlusion) using a temporary denture. However, in cases with poor primary implant stability, substantial bone augmentation, implants of reduced dimensions, parafunctio...

Preoperative planning for guided surgery includes software that shows a three-dimensional representation of the clinical and the radiographic matched data. The exact implant position and template design will be coded in the surgical guide. The template can be produced in specialized dental laboratories or one of the milling centers of the program m...

Full-guided surgery includes different steps that might lead to complications. The measurement inaccuracy within CBCT scans was evaluated to be up to 0.26 mm. The resolution of the extraoral scanner used to scan the cast models is specified by the manufacturer as less than 20 μm. Deviations in intraoral scans depend on the extension of the optical...

In the next chapters, we would like to discuss various initial situations and treatment options on the subject of guided surgery. For this purpose, we will present a number of clinical cases.

An initial treatment plan is key. There are three main existing workflows. In principle, a cast model or intraoral scans with a wax-up/mock-up and CBCT or CT scans of the patient are necessary. Subsequently, before planning implant positioning, these files containing the clinical and radiological information are matched together. Optical impression...

Every guided surgery kit is specific to the individual implant system. The surgical protocol, which includes implant size and drilling sequence, is followed. On the one hand, the pilot drilling or the complete implant bed preparation can be performed as part of half-guided surgery. With full-guided surgery, on the other hand, the implant is also in...

Full-guided surgery may be of enormous help, especially in full-arch edentulous cases. Due to the esthetic and hygienic challenges in full-arch crown and bridge prostheses, the use of a removable denture, such as an overdenture supported by a bar, telescope, or individual attachments, may be recommended in individual cases. A temporary tooth setup...

The pros of guided surgery are precise surgery planning, minimal invasiveness, exact implant positioning, shorter surgical time, and possibilities of a flapless approach. The cons of guided surgery include higher costs for the surgeon and patient, longer preoperative planning time, and difficult radiological estimation of bone quality and quantity...

From the very beginning, the most important advantages of guided surgery are a comprehensive diagnosis and treatment planning and the 3D examination of the anatomical condition in every case. Anatomical structures and bone quality may vary not only between female and male patients but also between both jaws and within adjacent implant sites. For th...

To minimize the postoperative risks posed by grafting autologous transplants for cleft repair, efforts are being made to improve grafting materials for use as potential alternatives. The aim of this study was to compare the bone graft quality of different bone substitutes including the gold standard autografts during the healing processes after cle...

Conventional anastomoses with interrupted sutures are challenging and inevitably associated with trauma to the vessel walls. The goal of this study was to evaluate a novel alternative adhesive-based suture-free anastomosis technique that uses an intraluminal stent. Overall, 120 porcine coronary vessels were analyzed in an ex vivo model and were exa...

Background Sutured anastomosis remains the gold standard in microvascular surgery. The procedure is not free of complications and is a time-consuming operation requiring a high level of experience. The aim of this study was to develop new methods for a stable, faster, and safer anastomosis using a novel biodegradable adhesive, VIVO, and a custom-ma...

A split thickness skin graft (STSG) or a full thickness skin graft (FTSG) are commonly used for donor site closure after raising a radial forearm flap. The aesthetic outcome of the donor site is frequently not satisfying for the patient. This study evaluated the aesthetic outcome of the donor site of a radial forearm flap covered with an STSG or FT...

After craniofacial trauma, symptoms like swelling and pain occur. Cooling reduces these symptoms but the optimal cooling temperature for a maximum benefit without adverse effects is unclear. 30 participants were cooled at 10 °C, 15 °C, 20 °C, 25 °C and 30 °C for 30 min. Before cooling and at 15, 30, 45 and 60 min after cooling, the skin blood flow,...

Facial fractures comprise a substantial part of traumatology. Due to aging of the population, over the last 20 years, there has been a pattern of redistribution of these fractures with a higher incidence at an older age. The aim of this study was to retrospectively analyze the epidemiology, pattern, and surgical management of facial fractures in ge...

Background: Orthognathic surgery can be carried out using isolated mandibular or maxillary movement and bimaxillary procedures. In cases of moderate skeletal malocclusion, camouflage treatment by premolar extraction is another treatment option. All these surgical procedures can have a different impact on the soft tissue profile. Methods: The cha...

Background Certification of multidisciplinary tumor centers is nowadays seen as the gold standard in modern oncological therapy for optimization and realization of guideline-based therapy and better outcomes. Single cases are reimbursed based on diagnosis-related groups (DRG). We aimed to review efficiency, cost analysis, and profitability followin...

Objectives The aim of this study was to evaluate the accuracy of fully guided orthodontic mini-implant (OMI) placements supported by tooth- (TBGs) or gingiva-borne silicone guides (GBGs) based on virtually superimposed lateral cephalograms on virtual plaster models.Materials and methodsLateral cephalograms and corresponding plaster models were virt...

Background Local anaesthesia plays a key role in many aspects of a dentist’s work. The required skills to perform anaesthesia successfully are acquired at university. To take advantage of the possibilities for new teaching formats, a blended learning concept for the local anaesthesia course was developed. The aim of the study was to compare the eff...

The aim of this study was to analyse the effect of zirconia and titanium surfaces on biofilm formation and host-derived parameters. Studies comparing zirconia and titanium surfaces were selected up to September 1, 2019. The outcome measures were surface roughness, contact angle, bacterial count, bacterial adherence, biofilm thickness, bacterial dis...

Objectives The purpose of this pilot porcine cadaver study was to evaluate the feasible temperature thresholds, which affect osteocyte viability and bone matrix in a preclinical setup, assessing the potential of thermal necrosis for implant removal for further in vivo investigations.Materials and methodsAfter implant bed preparation in the upper an...

Objectives The aim of this randomized observer-blinded split-mouth-study is to objectively assess the influence of a rubber drain on postoperative swelling using 3D face scans as measurement method and additionally evaluate pain, trismus and complications after the osteotomy of lower third molars.Material and methodsSeventy-two patients with symmet...

This book is an accurate introduction to guided implantology. As practitioners with many years of experience, the authors present an important basis for scientific findings and a valid decision-making aid for digital oral surgery. Readers are invited to learn step by step about full guided surgery. Numerous full color images demonstrate the anatomi...

Thermal treatment may reverse the osseointegration of implants and could become an atraumatic controlled method for implant removal in the future. The aim of this non-random in vitro study was to empirically identify suitable sources for a controlled heating process, in order to generate a homogenous temperature distribution at a threshold level of...

Background: Because of bisphosphonate medication, dental implantation with a subsequent infection poses a relevant risk factor to suffer from medication-related osteonecrosis of the jaw. This rat study evaluated different implant materials under systemic bisphosphonate delivery using micro-computed tomography (μCT) images. Methods: Fifty-four ra...

In the context of cleft repair in animal research in rat models, different areas can be used for bone grafting. The aim of the present study was to present the tuberosity of the ischium as a new donor site and to evaluate its quality in relation to an artificial alveolar cleft. Four weeks after creating experimental alveolar clefts in seven Wistar...

The incidence of skin cancer, which often affects the facial skin, has risen worldwide. After resecting such facial lesions, plastic reconstruction is necessary in most cases. The paramedian forehead flap (PFF) and the bilobed flap (BF) are commonly used for nasal reconstruction, but whether patients and physicians are satisfied with the esthetics...

The outcome of surgically assisted rapid palatal expansion (SARPE) can be affected by pterygomaxillary disjunction (PMD) and the distractor position. In this study, SARPE was performed, with or without PMD, in 20 fresh cadaver heads. Transverse expansion was conducted twice using a bone-borne distractor in the anterior and posterior positions, resu...

Objective The objective of this study was to assess the effect of an e-learning program including automatic speech recognition on outcomes assessment in interpreting panoramic radiographs at a dental school. Study Design For instruction in reporting findings on panoramic radiographs, 36 participants were divided randomly into 3 seminar groups. Gro...

Aim: This in vitro study aimed to evaluate the effects of implant designs on primary stability in different bone densities and bony defects. Methods: Five implant types (tapered-tissue-level, tissue-level, zirconia-tissue-level, bone-level, and BLX implants) were used in this assessment. The implants were inserted into four different artificial...

Magnesium alloys have exhibited a rapid rate of corrosion and thus early implant failure, so this study was designed to investigate the longer-term effects and in particular on wound closure. The aim of the study is to evaluate Mg-Ca-Zn Alloys as promising biodegradable implants in the field of maxillofacial surgery, which have so far never been ev...

Background: A teaching concept, that takes individual learning and personal belongings into account, is called the “sandwich principle.” This didactic method is an educational concept that alternates consecutively between individual and collective learning phases during a course. This study aimed to prove whether the application of the sandwich pri...

Purpose: Very high or low temperatures will lead to bone damage. The objective of this review was to analyze threshold values for thermal bone necrosis. Methods: Histological animal studies evaluating thermal effects on bone necrosis were selected via electronic and hand searches in English and German language journals until 1 November 2019. The...

Background: This study aimed at comparing bracket placement and excess bonding adhesive depending on different indirect bonding (IDB) techniques and bracket geometries. Methods: Four hundred eighty brackets without hook (WOH) and 360 with hook (WH) were placed on 60 plaster models. Three IDB techniques were tested: polyvinyl-siloxane vacuum-form (...

Objective: This retrospective study analyzed the dentoalveolar effects of pterygomaxillary disjunction (PMD) in surgically assisted rapid palatal expansion (SARPE) after orthodontic treatment. Study Design: Virtual study casts before and after orthodontic treatment involving SARPE were analyzed in 12 patients without (−) PMD and 15 patients with (...

Purpose: The purpose of this study was twofold: first, to evaluate the precision of guided orthodontic mini-implant (OMI) placement planned on virtual superimposition of plaster models and lateral cephalograms with regard to the bone support and, second, to investigate the effects of silicone guide extension. Methods: A total of 40 OMIs were pla...

The aim of this in vitro study was to determine the influence of bone density, orthodontic mini-implant (OMI) size, and the surgical procedure on temperature increase during implant site osteotomy and placement. OMIs of different sizes (2.0 × 7, 2.3 × 7, 2.0 × 11, and 2.3 × 11 mm) were placed in artificial bone blocks of different densities (D1–D4)...

Continuity defects of the jaw can be reconstructed with titanium plates or microvascular bone flaps; osteosynthesis plates are necessary for both. In this study we performed a retrospective review of patients treated with Medartis MODUS® Mandible Trauma/Reco 2.0-2.5, TriLock bridging plates, mandibulectomy and soft tissue free flap or reconstructio...

Objective Lateral cephalograms (LC) should be usable to evaluate the vertical bone height of the anterior maxilla for planning the placement of orthodontic mini‐implants (OMI). The purpose of this study is to determine the usability of LC for examining the real vertical dimension of the anterior palate. Setting and Sample Population LCs and corres...

Introduction Workplace‐based assessments are methods that can be applied for assessing competence and performance. One of these methods is the mini‐clinical evaluation exercise (mini‐CEX). This study was conducted to determine the role of mini‐CEX in students’ performance assessment on panoramic x‐ray reporting at dental radiology course. Material...

The purpose of this retrospective survey was to assess the esthetic aspects of adjacent zirconia and titanium implants in the anterior maxillary area. A total of 40 patients and 109 adjacent implants (17 patients with 47 titanium implants and 23 patients with 62 zirconia implants) was included. The primary aim of this survey was to assess the papil...

The concept of the clerkship at the Department of Oral and Maxillofacial Surgery was modified into a modern and sustainable teaching model with a flipped classroom approach. The aim was to prove whether these changes increased the students’ learning success. For the preparation of the clerkship, an e-learning module with 10 chapters was established...

The use of cold atmospheric pressure plasma (CAPP) as a bacterial decontaminant for chronic wounds has shown good results. The purpose of this in vitro study was to evaluate the bactericidal effects of CAPP on the cancellous area of the bone. Sterile glass slides and processed sterile human bone allografts 1, 2, 3, and 4mm thick were used for initi...

Objective The aim of this cadaveric study was to measure the transfer accuracy of orthodontic mini-implant placement at the anterior palate depending on tooth-borne or gingiva-borne guide support. Materials and methods Forty orthodontic mini-implants were placed paramedian in the anterior palate of 20 cadaver heads using tooth-borne (TBG) or gingi...

Auch wenn Langzeituntersuchungen nötig sind, um gesicherte Aussagen über die klinische Bewährung von Zirkonoxidimplantaten nach längerer Liegedauer treffen zu können, lässt sich auf der Grundlage des heutigen Erkenntnisstandes feststellen, dass diese Implantate eine Alternative zu herkömmlichen Titanimplantaten sein können. Ihre keramische Oberfläc...

Background: One surgical objective is creating an aesthetically satisfying outcome. The morbidity increases with age. Standard values for areas of the face, which are frequently surgically treated, are needed for the surgeon. Methods: 240 Caucasians aged 21-65 were divided into six subgroups by gender and age. They were scanned by a three-dimens...

This study aimed to evaluate the effect of implant size and bone condition on primary stability of orthodontic mini-implants with a view to predict the primary stability before insertion. Four-hundred and forty mini-implants of two different diameters (2.0 and 2.3 mm) and lengths (7 and 12 mm) were inserted at 11 different positions in human cadave...

Purpose: This study aimed to compare the effects of different orthognathic and camouflage treatments for correcting moderate skeletal class II and III malocclusions on the pharyngeal airway space (PAS). Materials and methods: Lateral cephalograms of 89 patients with moderate skeletal class II and III malocclusion (WITS up to 7 mm, -7 mm respecti...

Virtual surgical planning plays an increasingly important role in jaw reconstruction. The aim of the present study was the evaluation of the clinical applicability of a novel algorithm for automating virtual mandibular reconstruction using fibula flaps. The software uses Computed-Tomography of the facial skeleton and the lower leg of 63 subjects, i...

Purpose Harvesting bone from the ascending ramus of the mandible is a common procedure. However, mandibular fracture may occur after grafting bone blocks. This study aimed to investigate the resulting force distribution of stress and strain in the mandibular donor site after harvesting bone grafts of different sizes and various loadings. Methods F...

Purpose Facial proportions in younger people have been evaluated in several studies. However, the number of older people who need orthognathic surgery is growing steadily. The aim of this study was to evaluate facial morphology in Caucasians accounting for age and gender. Methods Three-dimensional facial scans of 240 healthy volunteers were taken....

After continuity resection of the mandible, reconstruction of continuity with a reconstruction plate and soft tissue can be an alternative to immediate osseous reconstruction in patients with advanced oral cancer. We evaluated exposure of the plate in such reconstructions by comparing the results of a radial forearm flap (RFF) with a vastus lateral...