Karl-Heinz Frosch

University Medical Center Hamburg - Eppendorf and BG Hospital Hamburg

Purpose There is a high risk of increasing the posterior tibial slope (PTS) during medially opening‐wedge high tibial osteotomy (mowHTO). Most recently, the idea of intentional simultaneous coronal and sagittal correction, using uniplanar cutting techniques has emerged. This study aims to examine the influences of variable hinge positioning and ost...

Compared to the anterior cruciate ligament injury, the rupture of the posterior cruciate Ligament (PCL) is the rarer condition. A high healing potential is attributed to the PCL in the literature, which is why conservative therapy is also considered important in addition to surgical treatment [1]. Posterior cruciate ligament rupture is often associ...

Introduction Distal radius fracture (DRF) is one of the three most common fractures of the human body with increasing incidences in all groups of age. Known causes of increasing incidence, such as ageing of the population or increased obesity, have been described and discussed. So far, literature reports ambivalent effects of body mass index (BMI)...

Purpose The purpose of this study was to examine the intra- and interobserver variability of an app-based analysis of the femoral tunnel position using the quadrant method in primary anterior cruciate ligament reconstruction. Materials and methods Between 12/2020 und 12/2021 50 patients who underwent primary anterior cruciate ligament reconstructi...

Purpose Arthroscopic reconstruction techniques for higher-grade posterolateral corner (PLC) injuries (Fanelli Type B, PoLIS LI-B) have not yet been validated in clinical studies. The open reconstruction technique described by Arciero is well-established and showed good restoration of joint stability in previous studies. This study aimed to compare...

Introduction Traditionally, plate osteosynthesis of the anterior column combined with an antegrade posterior column screw is used for fixation of anterior column plus posterior hemitransverse (ACPHT) acetabulum fractures. Replacing the posterior column screw with an infraacetabular screw could improve the straightforwardness of acetabulum surgery,...

Traumatic brain injury (TBI) leads to skeletal changes, including bone loss in the unfractured skeleton, and paradoxically accelerates healing of bone fractures; however, the mechanisms remain unclear. TBI is associated with a hyperadrenergic state characterized by increased norepinephrine release. Here, we identified the β 2 -adrenergic receptor (...

Background: Treatment of complex tibial plateau fractures remains a challenging task in clinical practice. Sufficient and appropriate preoperative decision making is essential for optimal treatment success and ultimately influences patient outcomes. Recently, the novel technique of 3D printing has proven to be beneficial for the preoperative manage...

The study aims to investigate the influence of patient- and fracture-specific factors on the occurrence of complications after osteosynthesis of patella fractures and to compare knee joint function, activity, and subjective pain levels after a regular postoperative course and after complications in the medium term. This retrospective, multicenter c...

Introduction Progressive collapsing foot deformity (PCFD), formally known as “adult-acquired flatfoot deformity” (AAFFD), is a complex foot deformity consisting of multiple components. If surgery is required, joint-preserving procedures, such as a medial displacement calcaneal osteotomy (MDCO), are frequently performed. The aim of this systematic r...

Post-traumatic deformities of the elbow, in particular cubitus varus and cubitus valgus, are often associated with chronic deformities, functional limitations and pain. Treatment of these deformities requires a high level of expertise and detailed preoperative planning. Today, 3D printing technology is used in addition to 3D computed tomography. Th...

The missed Monteggia injury is a rare but highly complex complication of an apparently harmless and sometimes overlooked injury in childhood. What are the options for conservative and surgical treatment? Which one is mainly used according to the current literature? What is the treatment algorithm? Evaluation of the current literature, presentation...

Osteoarthritis represents a chronic degenerative joint disease with exceptional clinical relevance. Polymorphisms of the CALCA gene, giving rise to either a procalcitonin/calcitonin (PCT/CT) or a calcitonin gene-related peptide alpha (αCGRP) transcript by alternative splicing, were reported to be associated with the development of osteoarthritis. T...

The posterolateral corner of the knee is composed of a multilayered complex of ligamentous, musculotendinous, and capsular structures, which interact in a synergistic stabilizing manner with the central structures, particularly the posterior cruciate ligament. Injuries of the posterolateral corner are generally accompanied by rupture of the posteri...

Background Investigation of the association between leg axis alignment and biochemical MRI in young professional soccer players in order to identify a potential influence of the leg axis on cartilage regions at risk. Methods Sixteen professional soccer players (21 ± 3 years) underwent static and dynamic leg axis analysis via radiation free DIERS f...

Background The relationship between remaining anterior knee laxity and poorer clinical outcomes after anterior cruciate ligament reconstruction (ACLR) may be underrated, and the criteria for failure of revision ACLR have not been defined. Purpose/Hypothesis To evaluate a possible association between remaining knee laxity and functional scores in p...

Background Posttraumatic osteoarthritis (OA) is a common disorder associated with a high socioeconomic burden, particularly in young, physically active, and working patients. Tranexamic acid (TXA) is commonly used in orthopaedic trauma surgery as an antifibrinolytic agent to control excessive bleeding. Previous studies have reported that TXA modula...

Proximal femur fractures (PFF) are a common injury in elderly patients that significantly impact mobility and daily living activities. Mortality rates in this population are also high, making effective treatment essential. Recent advances in intensive and geriatric care have enabled complex surgical interventions that were previously not feasible....

Background Minimally invasive approaches to the hip joint for total hip arthroplasty such as the DAA (“Direct Anterior Approach with bikini incision”) are increasingly utilized. According to the literature, this approach is more muscle-sparing, results in less postoperative pain, and achieves higher patient satisfaction. The existence of postoperat...

In a consecutive retrospective analysis of 190 patients treated with the Masquelet technique at the BG Klinikum Hamburg from January 2012 to January 2022, defect-specific features such as the extent and morphology of the defect were recorded, and their influence on the time to reach full weight-bearing of the affected limb was investigated. A total...

Aim Distal femur fractures (DFF) are rare, but associated with high complication rates and mortality, particularly in patients with osteoporosis. To improve preoperative assessment, we analyzed if cortical bone thickness on CT and AP radiographs is associated with clinical parameters of bone quality. Methods Retrospective single-center study of ad...

Knee dislocation (KD) is a rare but severe injury of the knee joint, with a high rate of concomitant neurovascular injuries. The severity of the ligamentous injury, which is classified according to the Schenck classification, the mechanism of injury, concomitant injuries and individual factors determine the treatment strategy in KD. Furthermore, a...

A clear recommendation regarding treatment strategy of fragility fractures of the pelvic ring is missing. The most typical fracture pattern is a lateral compression type injury with non-displaced fractures of the anterior pubic rami and a unilateral os sacrum fracture (FFP II). We hypothesized that operative treatment would be superior to conservat...

BACKGROUND: The CovidSurg-Cancer Consortium aimed to explore the impact of COVID-19 in surgical patients and services for solid cancers at the start of the pandemic. The CovidSurg-Gynecologic Oncology Cancer subgroup was particularly concerned about the magnitude of adverse outcomes caused by the disrupted surgical gynecologic cancer care during th...

Die korrekte Bohrkanalposition ist ein entscheidender Faktor für den Operationserfolg der vorderen Kreuzbandrekonstruktion. Die Smartphone App „ACL X“ (Linova Software GmbH, München, Deutschland) stellt eine Softwarelösung dar, mit der durch Abfotografieren eines intraoperativen Röntgenbildes geplante Bohrkanalpositionen nach der Quadrantenmethode...

Die femorale Bohrkanalfehllage ist einer der häufigsten Gründe für das Versagen einer vorderen Kreuzbandrekonstruktion (VKBR). In der Literatur gibt es Hinweise eines erhöhten Risikos für eine nicht anatomische Bohrkanalpositionierung durch weniger erfahrene Operateure. Die intraoperative fluoroskopische Kontrolle ist eine einfache Methode zur Verb...

Introduction Combined PCL injuries involving the posteromedial/-lateral corner (PMC/PLC) usually require surgical management. Literature shows controversy regarding the standards of treatment. Suture-augmented repair leads to excellent results in acute knee dislocations but has not been investigated clinically in combined PCL injuries. The purpose...

Zusammenfassung Tibiakopffrakturen stellen mehrheitlich komplexe und chirurgisch anspruchsvolle Gelenkfrakturen dar, die für ein zufriedenstellendes Ergebnis ein umfassendes Verständnis der Frakturmorphologie, der ligamentären und neurovaskulären Begleitverletzungen sowie der diagnostischen und therapeutischen Optionen erfordern. Hierzu ist ein sta...

Background: To evaluate the performance in activities of daily living (ADL), level of pain, mortality and rate of complications in patients with a pelvic ring fracture with sacral involvement who were treated conservatively compared to a surgically treated patient collective using percutaneous iliosacral screw fixation. Hypothesis: Conservative tr...

Aims Visualization of the subtalar joint surface in surgical management of calcaneal factures remains a big challenge and anatomic reduction of the articular surface is essential for a good clinical outcome. We hypothesize that video-assistance can provide superior fracture reduction compared to fluoroscopy and that nanoscopy (NSC) achieves more ex...

Background The combined injury of the medial collateral ligament complex and the anterior cruciate ligament (ACL) is the most common two ligament injury of the knee. Additional injuries to the medial capsuloligamentous structures are associated with rotational instability and a high failure rate of ACL reconstruction. The study aimed to analyze the...

Introduction: Apps, in general, are an integral part of our daily lives. To investigate the current usage behaviour of trauma surgeons and radiologists regarding medical apps in clinical practice and to find out if and how the current range of medical apps can be improved, we surveyed trauma surgeons and radiologists in northern Germany. Material...

Impaired fracture healing is of high clinical relevance, as up to 15% of patients with long-bone fractures display non-unions. Fracture patients also include individuals treated with selective norepinephrine reuptake inhibitors (SNRI). As SNRI were previously shown to negatively affect bone homeostasis, it remained unclear whether patients with SNR...

The posterolateral corner of the knee is composed of a multilayered complex of ligamentous, musculotendinous, and capsular structures, which interact in a synergistic stabilizing manner with the central structures, particularly the posterior cruciate ligament. Injuries of the posterolateral corner are generally accompanied by rupture of the posteri...

Traumatic brain injury (TBI) is associated with a hyperadrenergic state and paradoxically causes systemic bone loss while accelerating fracture healing. Here, we identify the beta2-adrenergic receptor (Adrb2) as a central mediator of these skeletal manifestations. While the negative effects of TBI on the unfractured skeleton can be explained by the...

Notch signaling regulates cell fate in multiple tissues including the skeleton. Hajdu-Cheney-Syndrome (HCS), caused by gain-of-function mutations in the Notch2 gene, is a rare inherited disease featuring early-onset osteoporosis and increased risk for fractures and non-union. As the impact of Notch2 overactivation on fracture healing is unknown, we...

Background: The Masquelet technique is a surgical procedure for the reconstruction of bone defects. During the first step, an osteosynthetically stabilized defect is filled with a cement spacer. The spacer induces a foreign body membrane, called a Masquelet membrane. In a follow-up procedure, the spacer is replaced by a bone graft, which ossifies...

Background: Distal femur fractures occur with an incidence of 4.5/100,000 and show a prevalence of 0.4%. Causes include low-impact trauma in older patients and high-impact trauma in younger patients without pre-existing medical conditions. The aim of this study was to perform a comprehensive evaluation of trauma mechanisms, trauma-promoting factor...

Acute knee dislocation is a rare but very complex injury. The diversity of the injury requires interdisciplinary cooperation for bony, ligamentous as well as vascular and nerve reconstruction. Since spontaneous reductions are common, there is an additional risk of overlooking or underestimating injuries. In addition to traffic accidents and sports...

Treatment of acute knee dislocations aims to repair any injured ligamentary structures according to Schenck classification including cruciate ligaments, peripheral structures, and menisci. Treatment of the cruciate ligaments is performed with an arthroscopic-assisted technique followed by medial arthrotomy. The posterior cruciate ligament is readap...

Zusammenfassung Die vasookklusiven Krisen der Sichelzellkrankheit gehen mit Knochennekrosen einher, welche eine endogene Keimbesiedlung und somit eine Osteomyelitis begünstigen. Dies bringt eine große Herausforderung für die Eradikation und Frakturversorgung mit sich. Ein 22-jähriger Patienten mit Sichelzellkrankheit erlitt eine mehrfragmentäre Hum...

Introduction Pelvic and acetabular fractures can result from work-related accidents and frequently require lengthy medical treatments. Consequently, high medical costs as well as delayed or absent return to work can be the consequence. Therefore, we aimed to study the socioeconomic consequences of work-related pelvic and acetabular fractures. Mater...

Background There is evidence on the clinical effectiveness of the Lemaire technique for lateral extra-articular tenodesis (LET) in patients undergoing revision anterior cruciate ligament reconstruction (ACLR), but the best fixation technique is unknown. Purpose To compare the clinical outcomes of 2 fixation techniques after revision ACLR: (1) onla...

Operation goal: The aims of the surgical treatment are the anatomical reduction of the articular surface and stabilization of a multifragmentary patella fracture with a distal pole fragment using plate osteosynthesis and additive suture tape cerclage to secure the distal fragment. Indication: Demonstration of the surgical procedure for a multifr...

Purpose Acute knee dislocation is a rare but devastating multi-ligamentous knee injury with only limited evidence-based surgical technique recommendations. The aim of this study was a comparison of two different anterior cruciate ligament (ACL) restoration techniques as part of an early total surgical care concept: (1) repair of ACL with additional...

Purpose In professional football (soccer), Achilles tendon ruptures are severe injuries. Video analysis promotes a better understanding of the underlying situational and biomechanical patterns, and provides a roadmap for future research to improve the management and prevention of Achilles tendon ruptures. The purpose of this study was to identify i...

Osteoid osteoma (OO) is a benign bone tumor that rarely occurs in the bones of the hand. Due to the comparatively non-specific symptoms when occurring in the hand, OO is often misdiagnosed at first presentation, posing a diagnostic challenge. In the present case study, six cases of phalangeal and carpal OO, treated surgically at our department betw...

Introduction Osteoid osteoma (OO) is a common benign bone tumor. OO is observed most frequently in the long bones, especially in the tibia and femur. When occurring in the bones of the hand, OO can be a diagnostic and therapeutic challenge. The aim of this study was to provide a systematic review of occurrence, symptoms, diagnosis and treatment opt...

The patella fracture is a rare fracture whose adequate treatment with preservation of the extensor apparatus is an important prerequisite for knee function. Demographic change and the associated increasingly complex fracture patterns, more frequent complications and greater functional demands, even in older patients, will lead to a change in existi...

A clear recommendation regarding treatment strategy of fragility fractures of the pelvic ring is missing. The most typical fracture pattern is a lateral compression type injury with non-displaced fractures of the anterior pubic rami and a unilateral os sacrum fracture (FFP II). We hypothesized that operative treatment would be superior to conservat...

In the treatment of tibial plateau fractures, anatomic reduction of the tibial joint surface is one of the key aspects for a good functional outcome. Particularly, complex fracture patterns show a high rate of postoperative malreduction with residual intra-articular step, often located in the posterior aspects of the tibial plateau. They are associ...

Background Patella fractures account for approximately 1% of all skeletal injuries. Treatment options are vast and no definitive conclusion on what option is the most beneficial could be made so far. Plate osteosynthesis appears to gain in importance. We aim to give insight into the more recent trends and developments as well as establish the epide...

Objective Bone stress injuries (BSIs) are classified in clinical practice as being at low- or high-risk for complication based on the injury location. However, this dichotomous approach has not been sufficiently validated. The purpose of this systematic review was to examine the prognostic role of injury location on return-to-sport (RTS) and treatm...

Since the introduction of widely available e-scooter rentals in Hamburg, Germany in June of 2019, our emergency department has seen a sharp increase in the amount of e-scooter related injuries. Despite a rising number of studies certain aspects of e-scooter mobility remain unclear. This study examines the various aspects of e-scooter associated inj...

Background It is known that specimen collection followed by histopathological workup is the core of evidence-based medical therapy of musculoskeletal tumors. There exist many controversies about how a biopsy should be performed. While some centers recommend minimal invasive biopsy procedures, mostly the core needle biopsy (CNB), others prefer the i...

The treatment of extra-articular proximal tibial fractures is a therapeutic challenge due to the frequently significant soft tissue injury, the effect of the deforming forces and the need for an exact restoration of the bony alignment. Various methods of osteosynthesis are available for surgical stabilization. The locking plate osteosynthesis is th...

Purpose The purpose of this study is to systematically review multiligament knee injury (MLKI) outcome studies to determine definitions of arthrofibrosis (AF) and provide information about incidence, management as well as potential risk factors. Methods A systematic literature search was performed (PubMed and Cochrane library) following the PRISMA...

Introduction The objective of this investigation was to compare different techniques to improve visualization and reduction in tibial plateau fractures involving the central lateral segments. Methods Matched pairs of pre-fractured cadaveric tibial plateau fractures that include the central lateral segments were treated by either an anterolateral a...

Introduction Complex ankle fractures frequently involve the posterior malleolus. Many classifications describing posterior malleolar fractures (PMF) exist. The aim of this study was to provide a systematic literature review to outline existing PMF classifications and estimate their accuracy. Methods The databases PubMed and Scopus were searched wi...

Intermittent injections of parathyroid hormone (iPTH) are applied clinically to stimulate bone formation by osteoblasts, although continuous elevation of parathyroid hormone (PTH) primarily results in increased bone resorption. Here, we identified Calca , encoding the sepsis biomarker procalcitonin (ProCT), as a novel target gene of PTH in murine o...

Background: Optimal treatment of proximal humeral fractures (PHF) is still controversial. Therefore, we aim to investigate the influence of fracture reduction after intramedullary nailing of a PHF on the clinical outcome. Methods: Patients treated with intramedullary nail for PHF from 2013-2018, (minimum follow-up 12 months) were retrospectively...

Persisting patellar maltracking following surgical realignment often remains unseen. The aim of this study was to analyze the effects of realignment procedures on patellofemoral kinematics in patients with patellofemoral instability (PFI) and patellofemoral maltracking (PM) by using dynamic magnetic resonance imaging (MRI). Patients planned for sur...

Introduction Complex ankle fractures frequently include the posterior malleolus (PM). Despite advances in diagnostic and treatment strategies, PM fracture involvement still predisposes to worse outcomes. While not incorporated into the most common PM fracture classifications, the presence of an intercalary fragment (ICF) complicates treatment. This...

Traumatic or iatrogenic sciatic nerve injury, but not superior gluteal nerve injury, is a well described complication after acetabular fractures. Most often, sciatic nerve injuries occur in fractures involving the posterior column/wall with a hip dislocation and posterior fracture displacement resulting in narrowing of the greater sciatic foramen a...

Purpose The outcome of a tibial plateau fracture (TPF) depends on the fracture reduction achieved and the extent of soft-tissue lesions, including lesions in the ligaments, cartilage, and menisci. Sub-optimal treatment can result in poor knee function and osteoarthritis. Preoperative planning is primarily based on conventional X-ray and computed to...

Introduction Childhood cancer is a leading cause of death. It is unclear whether the COVID-19 pandemic has impacted childhood cancer mortality. In this study, we aimed to establish all-cause mortality rates for childhood cancers during the COVID-19 pandemic and determine the factors associated with mortality. Methods Prospective cohort study in 10...

(1) Background: In treating medial unicompartmental gonarthrosis, medial open wedge high tibial osteotomy (mOWHTO) reduces pain and is intended to delay a possible indication for joint replacement by relieving the affected compartment. This study aimed to investigate the influence of the osteotomy height with different hinge points in HTO in genu v...

Introduction The aim of this study was to compare the reduction quality of the anterolateral (AL) and modified posterolateral approach (PL) in lateral tibial plateau fractures involving the posterior column and central segments. Methods Matched pairs of pre-fractured cadaveric tibial plateau fractures were treated by either AL approach (supine pos...

Zusammenfassung Glenoidfrakturen stellen im klinischen Alltag eine Rarität da. Neben hochenergetischen Traumata finden sich häufig Luxationsereignisse als Ursache. Nicht nur die Frakturmorphologie, sondern auch das zugrunde liegende Trauma haben einen Einfluss auf die richtige Entscheidung für die weitere konservative oder operative Behandlung. Ins...

It is known that specimen collection followed by histopathological workup is the core of evidence-based medical therapy of musculoskeletal tumors. There exist many controversies about how a biopsy should be performed. While some centers recommend minimal invasive biopsy procedures, mostly the core needle biopsy (CNB), others prefer the incisional b...

Despite increasing improvements in the outcome of arthroscopic reconstruction of ligamentous injuries of the knee joint, recurrent instability remains a complication that should not be underestimated, with considerable limitations of the quality of life. The influence of the frontal and sagittal joint axes on the peripheral ligament complex has not...

Zusammenfassung Bei einer Knieluxation handelt es sich um eine besonders schwere Form der Multiligamentverletzung. Aufgrund der häufig hohen Verletzungskomplexität existiert eine Vielfalt unterschiedlicher Diagnostik- und Versorgungsstrategien. Mit dem Ziel evidenzbasierter Therapieempfehlungen richtet sich die S2e-Leitlinie „Knieluxation“ an alle...