Kilian Wegmann

• Prof. Dr.
• Medical Doctor at OCM München

Background Numerous single- and double-row repair techniques with simple and modified stitches have been described for subscapularis tendon tears. Purpose/Hypothesis This study aimed to uniformly evaluate the influence of 4 different repair techniques on the biomechanical performance of fixation for full-thickness subscapularis tendon tears. It wa...

The elbow is a complex joint that relies on an intricate system of primary and secondary as well as static and dynamic stabilizing structures. The elbow joint is a heavily loaded area of the upper extremity. Moreover, it is prone to injuries, as it is exposed during falls. Rheumatic diseases often also affect the elbow joint. Deficits in elbow stab...

The elbow is a complex joint that relies on an intricate system of primary and secondary stabilizers, which are differentiated into static and dynamic structures. Knowledge of these structures is of utmost importance for the successful treatment of the broad variability in elbow pathologies. This chapter will display elbow anatomy in detail. Theref...

If no comminution is present, displaced fractures of the capitulum, the radial head, and the coronoid process are amenable to arthroscopically assisted reduction and internal fixation. Arthroscopy facilitates not only fracture reduction but also the evaluation of associated injuries around the elbow joint. After anatomic fracture reduction, K-wires...

Purpose This biomechanical study aimed to investigate the effectiveness of a hinged elbow orthosis in reducing passive valgus forces following medial ulnar collateral ligament (UCL) injuries of the elbow joint. The hypothesis tested was that a hinged elbow orthosis reduces these passive valgus forces. Methods Eight fresh frozen cadaveric elbow spe...

Introduction Over the last decades, arthroscopic surgery has become increasingly relevant as its minimally invasive approach offers many benefits. To investigate the risks of orthoscopic surgery at the elbow, this study aimed to investigate the development of temperatures in elbow joints while performing radiofrequency ablation in arthroscopic surg...

Searching for quick determinable biomarkers with high sensitivity and specificity is necessary to improve and optimise the early diagnosis of periprosthetic elbow infection (PEI). Therefore, this study's objective was to evaluate the diagnostic value of synovial fluid interleukin-6 (IL-6) levels for diagnosing PEI in total elbow arthroplasty. Twelv...

Anatomical variations of the concave shaped retrocondylar ulnar groove (RUG) can contribute to ulnar nerve instability. However, there are currently limited available standardized data describing the anatomy of the RUG based on radiologic imaging, such as computed tomography (CT). This study aims to provide a comprehensive description and classific...

Introduction Osteochondrosis dissecans (OCD) at the capitellum is a common pathology in young patients. Although arthroscopic interventions are commonly used, there is a lack of information about the accessibility of the defects during elbow arthroscopy by using standard portals. Materials and methods An elbow arthroscopy using the standard portal...

Elbow trauma is often accompanied by a loss of independence in daily self-care activities, negatively affecting patients' quality of life. Finite element models can help gaining profound knowledge about native human joint mechanics, which is crucial to adequately restore joint functionality after severe injuries. Therefore, a finite element model o...

Purpose Postoperative soft tissue swelling is a significant factor influencing outcomes after elbow surgery. It can crucially affect important parameters such as postoperative mobilization, pain, and subsequently the range of motion (ROM) of the affected limb. Furthermore, lymphedema is considered a significant risk factor for numerous postoperativ...

A thorough understanding of the anatomical and biomechanical particularities of the elbow is required to provide an optimal management of pathologies. The forearm joint is highly effective and based on the complex anatomy of the elbow. Besides the osseous anatomy, the understanding of the capsular ligamentous complex and the muscles is essential to...

Introduction Varus posteromedial rotational injury mechanisms leads to fractures of the coronoids process` anteromedial facet. As these fractures are often unstable, rapid fracture treatment is vital to prevent progressive osteoarthritis. Materials and Methods Twelve patients with a fracture of the anteromedial facet treated surgically were enroll...

Introduction Nailing of the proximal humerus is an established method for the treatment of proximal humerus fractures. Choice of the correct length for potentially four proximal locking screws is essential for postoperative outcome. Due to positioning of the patient, intraoperative determination of the correct length of the anteroposterior (AP) scr...

Zusammenfassung Traumatische Sehnenverletzungen am Ellenbogen können komplex und mannigfaltig sein. Der Unfallhergang bestimmt wesentlich das Verletzungsausmaß. So kann ein Sturz auf den ausgestreckten Arm zu einer Ruptur der Trizepssehne mit möglichen begleitenden ligamentären Verletzungen wie beim ulnaren Kollateralband oder auch einer Ellenbogen...

Studies on graft reconstruction techniques for ruptured thumb metacarpophalangeal (MCP) ulnar collateral ligaments (UCL) do not consider the variety of MCP joint morphology. Optimal reconstruction method for flat MCP joints is therefore unclear. Twenty-four fresh-frozen, human thumbs were tested for flexion, extension and valgus stability of the MC...

Objectives: Buckle fractures of the distal forearm are a common fracture entity in children treated conservatively. Diagnostics primarily include radiographs in 2 planes. Inadequate images may occur in the mostly very young patients. Therefore, additional lateral radiographs are often obtained to assess a possible angular tilt. The aim of this stu...

The radiologic evaluation of the sagittal angulation of the distal humerus is commonly based on standard lateral radiographs. However, lateral radiographs do not allow to examine the lateral angulation of the capitulum and the trochlea, separately. Although this problem could be approached via computed tomography, there are no data available descri...

Introduction The aim of the present study was to develop a technical process to reproducibly generate terrible triad injuries (TTI) in fresh-frozen human cadaveric specimens, while leaving the skin intact. Such “pre-fractured” specimens, used for scientific analysis and for surgical education, might help to improve current treatment, which is compl...

Purpose Indirect fixation of coronoid process fractures of the ulna, especially arthroscopically, offers the possibility to avoid extensive medial surgical approaches. However, optimal placement of K-wires for cannulated screw fixation is technically challenging. The aim of the present study was to present guide values for K-wire placement for indi...

Purpose The optimal screw placement in arthroscopically assisted fixation of radial head fractures is still an issue and no guiding methods have been evaluated in the recent literature. The study hypothesis was that using a “reference k-wire” percutaneously inserted in and parallel to the radiocapitellar joint would enable to achieve a trajectory m...

With proven impact of statistical fracture analysis on fracture classifications, it is desirable to minimize the manual work and to maximize repeatability of this approach. We address this with an algorithm that reduces the manual effort to segmentation, fragment identification and reduction. The fracture edge detection and heat map generation are...

Purpose Interposition arthroplasty for the post-traumatic osteoarthritic elbow is a salvage procedure used in young and active patients and remains a rare and unexplored therapeutic option. Methods We systematically reviewed the available literature searching electronic databases, MEDLINE using the PubMed interface and EMBASE. The primary objectiv...

This article provides an overview of the role of nonsurgical treatment in common elbow injuries and presents the special features of selected conservative treatments. In the case of acute injuries (fractures, ligamentous elbow dislocations) or chronic pathologies (e.g., lateral/medial epicondylitis, elbow stiffness), a treatment algorithm should be...

Traumatic triceps tendon ruptures are rare and known to result in substantial disability unless appropriate surgical treatment is performed. A traumatic rupture can occur due to a fall onto the outstretched hand. Tearing of the triceps tendon results in a valgus load onto the elbow, which can lead to injuries to the radial head/neck and/or the ulna...

Good to very good clinical results can be achieved in older patients with the implantation of a total elbow prosthesis in cases of distal humeral fractures by taking the morphological features of the fractures, the bone quality as well as the individual patient requirements and variables into account. The most commonly used design is the cemented s...

Introduction Open reduction and internal fixation (ORIF) of comminuted coronal shear fractures of the distal humerus is challenging. When a concomitant lateral condyle fracture is present, it may be used for a trans-fracture approach to facilitate exposure and fracture reduction. This study aimed to investigate the frequency of lateral condyle frac...

Background: Fractures of the coronoid process require adequate treatment, as otherwise they often lead to chronic instability and the development of rapidly progressive cubital osteoarthritis. Commonly, such patients are treated surgically; however, a defined fraction of patients might benefit from conservative treatment. Methods: We systematicall...

Background Complex proximal humeral fracture ranks among the most common fracture types, especially in elderly patients. In locked plate fixation of proximal humerus fractures, the calcar is deciding for screws providing further medial column support. To date, the biomechanical effect of the length of these calcar screws is not well known. The purp...

Introduction In regard of surgical training, the reproducible simulation of life-like proximal humerus fractures in human cadaveric specimens is desirable. The aim of the present study was to develop a technique that allows simulation of realistic proximal humerus fractures and to analyse the influence of rotator cuff preload on the generated lesio...

Introduction Preventing nerve injury is critical in elbow surgery. Distal extension of medial approaches, required for coronoid fracture fixation and graft-replacement, may endanger the median nerve. This study aims to describe an easily identifiable and reproducible anatomical landmark to localize the median nerve distal to the joint line and to d...

Purpose E-scooters are a new type of urban transportation utilized in Germany since June 2019, primarily in larger cities in the context of sharing offers. Such electrically operated standing scooters can be driven at a maximum speed of 20 km/h. A helmet is not mandatory. The aim of this prospective study is to document the injury patterns over the...

Introduction Stiffness after elbow injuries can severely limit daily life. If adequate conservative treatment does not result in satisfactory improvement of elbow function, surgical intervention should be considered. Whether an open or arthroscopic procedure is preferable is still a topic of debate and a systematic review of functional outcomes is...

Objectives:. In view of the increased attention to reverse shoulder arthroplasty (rTSA) as a treatment for complex proximal humeral fractures in the elderly, the present study analyzes in-hospital complications and the postoperative management of rTSA versus open reduction and internal fixation (ORIF). Methods:. We retrospectively reviewed patients...

Purpose Olecranon fractures, especially with a small proximal fragment, remain a surgical challenge. Soft tissue irritation and affection of the triceps muscle bear a risk of complications. In order to find an area for a soft-tissue sparing placement of implants in the treatment of olecranon fractures, we aimed to define and measure the segments of...

Background: Purpose of this study was to investigate the primary stability and displacement tendencies of an external fixation system in 2 different configurations in comparison to locking plate fixation in a 3-part proximal humerus fracture model. Methods: 21 fresh-frozen human cadaveric proximal humerus specimens were divided into 3 groups of...

Metacarpal fractures are a type of fracture which trauma surgeons face frequently. Restoration of hand function is the primary objective. The aim of this study was to investigate whether life-like fractures of human cadaveric metacarpals with intact soft-tissue envelope could be simulated for surgical education. Six fresh-frozen human distal forear...

Background Lateral collateral ligament (LCL) tears are frequently observed in fractures and dislocations of the elbow. Recent biomechanical evidence suggests that additional ligament augmentation may improve repair stability. The aim of this biomechanical in-vitro study was to compare the resistance of a locking suture repair of the LCL with a liga...

Background Due to the complexity of distal humerusfractures and often poor bone quality in elderly patients, these entities remain a challenge. However, because of a high rate of complications related to total elbow prostheses, reconstruction of distal humerus fractures should still be considered a therapeutic option, also in the elderly patient. T...

Arthroscopically assisted reduction and internal fixation of select elbow fractures offers the benefits of a minimally invasive procedure and provides good evaluation of anatomic fracture reduction and the detailed detection of concomitant injuries.

The stability of the elbow joint depends on the bony, ligamentous, and musculoskeletal structures of the elbow. Arthroscopic instability tests are an add-on to patient’s history, clinical examination, and standard imaging studies for diagnosing both mild and complex forms of instability. Arthroscopic examination is therefore an option in clinically...

The radial head is an important secondary stabilizer of the elbow. The Mason classification is commonly used for the characterization and planning of fracture treatment. The incidence of associated ligament injuries rises with increasing severity of the fracture. With conservative therapy, good results can be achieved in up to 95% of Mason 1 fractu...

Fractures of the distal humerus are challenging, and reconstruction of those fractures should be performed in centers with upper extremity surgery. This chapter covers the treatment of AO type B3 and type C fractures.

Olecranon fractures make up a significant amount of upper extremity fractures (10%). They usually occur from a fall on the elbow with direct impaction. The majority of these are simple fractures (80%) with not more than two fragments. The most common classification is the Mayo classification, which distinguishes three types with or without comminut...

The coronoid process stabilizes the elbow against axial, varus, and valgus forces. Injuries to the coronoid process typically occur during dislocations in combination with radial head injuries, isolated injuries to the tip or the anteromedial facet or as part of more complex injuries of the proximal ulna. They are regularly accompanied by soft-tiss...

The aim of this study was to investigate whether life-like fractures of human cadaveric mandibles with a focus on the condylar process and the intact soft tissue envelope could be simulated. A total of nine fresh-frozen human head specimens were fractured in a custom-made drop-test bench. This reproducible method is based on a weight falling from a...

Der M. triceps brachii stellt den relevanten Streckapparat des Ellenbogens dar. Als zweigelenkiger Muskel spielt er ebenso eine Rolle bei der Extension im Schultergelenk. Damit ist der Trizeps essenziell für die suffiziente Funktion der oberen Extremität. Distal gehen die drei Muskelbäuche in die Trizepssehne über, welche am proximalen Olecranon kn...

Frakturen des Radiuskopfes mit zwei Fragmenten, transverse Koronoidfrakturen sowie koronare Abscherfrakturen des distalen Humerus/Capitulum humeri ohne Trümmerzone eignen sich potentiell für eine arthroskopisch-gestützte Osteosynthese. Die Vorteile des arthroskopischen Vorgehens liegen in der geringeren Zugangsmorbidität, der exakteren Beurteilbark...

Der prothetische Gelenkersatz des Ellenbogengelenks bei nichtrekonstruierbaren Frakturen des distalen Humerus stellt allen voran bei geriatrischen Patienten eine sinnvolle Therapieoption dar. Insbesondere bei mehrfragmentären koronaren Abscherverletzungen (B3-Frakturen) kann dabei statt einer Totalendoprothese die Implantation einer Hemiprothese er...

Introduction In this study we investigated if realistic fracture patterns around the hip can be produced on human cadaveric specimens with intact soft tissue envelope. Possible applications of such fractured specimens would be in surgical training. Materials and methods 7 cadaveric specimens (2 male, 5 female, 2 formalin-fixed, 5 fresh-frozen) wer...

BACKGROUND Additional stabilization of the "comma sign" in anterosuperior rotator cuff repair has been proposed to provide biomechanical benefits regarding stability of the repair. PURPOSE This in vitro investigation aimed to investigate the influence of a comma sign-directed reconstruction technique for anterosuperior rotator cuff tears on the pr...

Background Radial head arthroplasty is a common procedure in elbow surgery. It has been shown to be of benefit for the patients, but there also are relevant complications that should be prevented if possible. One significant complication is overlengthening of the radial head prosthesis. In overlengthening, the head of the prosthesis overextends the...

Introduction Radial head fractures account for the majority of bony elbow injuries. The individual treatment options have been described in detail. In some cases, however, an unusual concomitant injury occurs, which can significantly impede primary osteosynthesis and healing. This concomitant injury can be an interposing cartilaginous capitellar fr...

Background The brachialis muscle lies in close anatomic relation to the anterior capsule of the elbow joint. The contribution of the brachialis muscle to elbow stability has not yet been fully investigated. Therefore, the aim of this biomechanical in-vitro study was to analyze its influence on joint stability. Methods Nine fresh frozen cadaveric e...

Zusammenfassung Das Ellenbogengelenk wird durch die beteiligten Knochen, Bandstrukturen und Sehnen von Extensoren und Flexoren stabilisiert. Die Instabilität des Gelenks ist nicht genau definiert, daher spielt die Bildgebung für die genaue Diagnostik eine entscheidende Rolle. Dieser Beitrag stellt die beteiligten Strukturen, die Formen der Instabil...

Background: Double-row (DR) and transosseous-equivalent (TOE) techniques for rotator cuff repair offer more stability and promote better tendon healing compared with single-row (SR) repairs and are preferred by many surgeons. However, they can lead to more disastrous retear patterns with failure at the medial anchor row or the musculotendinous junc...

Background Radial head fractures represent a common pathology that can cause permanent disability, especially if not treated correctly. Plain radiographs as well as computed tomography (CT) scans represent important diagnostic measures. The specific differences between these two imaging modalities with regard to diagnosis of radial head fractures h...

Background: Operative management of pilon fractures, especially high-energy compression injuries, is a challenge. Operative education is of vital importance to handle these entities. Not rarely, it is cut by economics and staff shortage. As public awareness toward operative competence rises, surgical cadaver courses that provide pre-fractured spec...

Purpose Use of a relatively larger glenosphere with some larger overhang helps to minimize posterior impingement and some degree of glenoid lateralization is also beneficial in reverse shoulder arthroplasty (RSA). The optimal amounts of inferior overhang and lateralization are not agreed upon. The purpose of this in-vitro biomechanical study is to...

Background : Joint replacement surgery as a treatment for complex proximal humeral fractures is an established option, especially in the elderly. In light of the increased attention to reverse total shoulder arthroplasty (rTSA), this study has analyzed the outcomes of patients with primary reverse arthroplasty and after secondary reverse arthroplas...

Background The incidence of periprosthetic fractures of the proximal humerus is gradually increasing, following an increase in reverse shoulder arthroplasties (RSA) in the last years. Locking plate fixation and revision arthroplasty are both valuable treatment methods. However, the primary stability of fixation methods for peri-prosthetic fractures...

Introduction Lateralization of the metaglene reduces scapular notching or impingement. However, the effect on joint mobility remains unclear. With increased attention to reverse shoulder arthroplasty over the past years, the aim of this biomechanical study is to analyze the effect of metaglene lateralization on range of motion in reverse shoulder a...

There are many possible complications following radial head arthroplasty. The most obvious is normally stiffness. In many cases there is a combination of problems such as stiffness, instability and cartilage damage. Differentiating the main cause is often difficult.

Radial head fractures account for the majority of bony injuries to the elbow. The usual clinical signs include hemarthrosis, pain and limitations in movement. The standard diagnostic tool is radiological imaging using X‑rays and for more complex fractures, computed tomography (CT). Concomitant ligamentous injuries occur more frequently than expecte...

The elbow is an intricate joint due to its complex anatomy and the not yet completely understood biomechanics. Therefore, elbow injuries remain a difficult entity when surgical repair is necessary. A multitude of different ligamentous injuries, fractures and fracture dislocations are known. But treatment protocols are controversial and complication...

Objectives: Lumbar spinal stenosis (LSS) and lumbar disc herniation (LDH) are often accompanied by frequently occurring leg cramps severely affecting patients' life and sleep quality. Recent evidence suggests that neuromuscular electric stimulation (NMES) of cramp-prone muscles may prevent cramps in lumbar disorders. Materials and Methods: Thirty...

Zusammenfassung Hintergrund Die laterale Epikondylopathie, auch Tennisellenbogen genannt, ist ein häufiges Krankheitsbild im klinischen Alltag. Neben den degenerativen Veränderungen im Bereich des Extensorenursprungs, meist basierend auf Überbelastung oder Mikrotraumata, können noch weitere Veränderungen ursächlich für den lateralen Ellenbogenschm...

Background: Fractures of the radial head represent the most common bony injury of the elbow in adults. Radial head fractures are classified according to Mason or one of its classification modifications. Current literature does not indicate consensus on whether to treat isolated stable type II radial head fracture patterns with open reduction and in...

Introduction This study aimed to describe the involvement of the lesser sigmoid notch in fractures to the coronoid process. We hypothesized that injuries to the lateral aspect of the coronoid process regularly involve the annular ligament insertion at the anterior lesser sigmoid notch. Material and Methods Patients treated for a coronoid process fr...

Background Supracondylar fractures of the humerus are the most common type of elbow fractures in childhood. Due to the potential risk of severe complications, trauma surgeons should address them with caution. Avascular necrosis of the trochlea presents a rare but oftentimes disabling complication and should not be underestimated. The aim of the pre...

Purpose: The aim of this study was to compare several osteosynthesis techniques (intramedullary headless compression screws, T-plates, and Kirschner wires) for distal epiphyseal fractures of proximal phalanges in a human cadaveric model. Methods: A total of 90 proximal phalanges from 30 specimens (index, ring, and middle fingers) were used for thi...

Background Medial epicondylitis is a common orthopedic condition that typically results from overuse or previous microtrauma of the flexor-pronator mass. Repetitive eccentric loading of the muscles leads to subsequent degeneration of the flexor tendons. Diagnosis Patients present with a painful elbow. In the case of concomitant elbow pathologies,...

Background The coronoid process plays a vital role in preserving elbow stability. In cases of acute or chronic deficiency of the coronoid process, reconstruction is warranted in order to restore stability and to avoid early joint degeneration. The distal clavicle might be a useful osteochondral autograft for coronoid reconstruction with low donor-s...

Background: Fractures of the anteromedial facet (AMF) of the coronoid process are caused by a varus posteromedial rotational injury force, leading to instability in the ulnohumeral joint. AMF fractures are usually accompanied by avulsion of the lateral ulnar collateral ligament (LUCL). O'Driscoll's description and classification of AMF coronoid fr...

Aim of surgery: The placement of an external elbow fixator can be statically carried out as temporary stabilization or as a hinged movement fixator. As a hinged movement fixator a functional follow-up treatment is possible due to control of the joint guidance and reduction of the compromising forces on the osteoligamentous structures. Indications...

Background Radial head replacement is an established option in patients with comminuted radial head fractures and complex elbow trauma. While studies demonstrated that asymptomatic radiolucencies around the stem are common, the incidence and clinical significance of bone loss at the proximal part of the radius, just distal to the neck of the prosth...

Background Prosthetic replacement of the proximal humerus with reverse shoulder arthroplasty (RSA) is an established means of treatment. Due to its unique biomechanical characteristics, RSA can restore shoulder function to a satisfying level in the case of cuff tear arthropathy, arthritis, and fractures. However, complications are frequent in RSA,...

PURPOSE Mechanical impingement at the narrow radioulnar space of the tuberosity is believed to be an etiological factor in the injury of the distal biceps tendon. The aim of the study was to compare the pressure distribution at the proximal radioulnar space between 2 fixation techniques and the intact state. METHODS Six right arms and 6 left arms...

Background Economic burden and personnel shortages lead to a reduction in the time spent on surgical training of young resident physicians. This underlines the importance of courses for learning and optimizing surgical skills. Particularly for orthopaedic trauma surgery, training on fractured cadaveric specimens has proven highly useful. The presen...

Background Because of poor soft-tissue coverage at the proximal ulna and prominent posteriorly positioned implants, hardware removal remains the most common reason for revision surgery of olecranon fractures that were operatively treated using plate osteosynthesis. We hypothesized that low-profile double-plate osteosynthesis would reduce the number...

Background Aim of this biomechanical study was to investigate the anchorage of pedicle screws in osteoporotic vertebrae using two different preparation techniques (probe versus drill-assisted). Methods Twelve thoracic vertebrae were used for the study. The right and left pedicles of the vertebra were prepared with a thoracic probe or a 3.2 mm dril...

Background: Correct sizing is challenging in radial head replacement and no consensus exists on the implant's optimal height and width to avoid elbow stiffness and instability. Studies exists, suggesting how to appropriately choose the implant size, but the manner by which the fracture pattern influences the surgeons' operative choices was not inv...

Introduction: Surgical education consists often times of a discrepancy between necessary amount of provided operative teaching and amount of organizational and ward duties. Operative education is often cut to a minimum. As public awareness toward surgical competence raises, so must the educational system. Courses that provide pre-fractured cadaver...

Background Joint registries provide invaluable data on primary arthroplasties with revision as the endpoint; however, the revision outcomes are often excluded. Therefore, a PROSPERO registered review (CRD42015032531) of all revision studies in North America and Europe was conducted to evaluate demographics, etiologies and indications, implant manuf...

Background Screw loosening is a major complication following spondylodesis. While several modifications increase screw stability, some, such as screw augmentation, are associated with potential complications; new techniques are needed to minimize the risk of screw loosening without increasing complication rates. Methods 13 fresh-frozen human lumba...

Traumatische Ellenbogenluxationen und Luxationsfrakturen stellen schwerwiegende Verletzungen dar, welche die Stabilität des Ellenbogengelenks gefährden. Aufgrund der Komplexität dieser Verletzungen sind die Komplikationsmöglichkeiten vielgestaltig. Ein eingehendes Verständnis der anatomischen und biomechanischen Zusammenhänge ist nötig, um ein opti...