Michael Tobias Hirschmann

Kantonsspital Baselland (Bruderholz, Liestal, Laufen), Department of Orthopaedic Surgery and Traumatology · www.kniedoktor.ch

Bei ungefähr einem Drittel aller Patienten nach Knieprothesen-Operation finden sich persistierende oder wiederkehrende Schmerzen und/oder eine Unzufriedenheit. Klinisch zeigt sich ein sehr komplexes und individuell sehr unterschiedliches Beschwerdebild. Die diagnostische Abklärung ist schwierig und sollte durch einen in der Knieprothetik spezialisi...

Since the early years of orthopaedics, it is a well-known fact that anatomy follows function. During the evolution of mankind, the knee has been optimally adapted to the forces and loads acting at and through the knee joint. However, anatomy of the knee joint is variable and the only constant is its complex function. In contrast to the time of open...

Purpose: There is a lack of knowledge about the joint line orientation of the femur and tibia in non-osteoarthritic knees. The primary purpose of the present study was to evaluate the orientation of the joint lines in native non-osteoarthritic knees using 3D-reconstructed CT scans. The secondary purpose was to identify knee phenotypes to combine th...

Purpose The currently used system to classify the lower limb alignment (neutral, varus, valgus) does not consider the orientation of the joint line or its relationship to the overall lower limb alignment. Similarly, current total knee arthroplasty (TKA) alignment concepts do not sufficiently consider the variability of the native coronal alignment....

Objectives: The Attune total knee arthroplasty (TKA) has been used in over 600 000 patients worldwide. Registry data show good clinical outcome; however, concerns over the cement-tibial interface have been reported. We used retrieval analysis to give further insight into this controversial topic. Methods: We examined 12 titanium (Ti) PFC Sigma i...

Purpose >The aim of this multicenter study was to analyze the potential impact of patient demographics and cementation technique towards the development of radiolucent lines (RLLs) in primary total knee arthroplasty (TKA). It was hypothesized that cementation techniques, including higher cement volume, double‐layer cementation technique and hardeni...

Background Contamination of sterilized surgical instruments is not a typically suspected source of increased infection rate, especially if no abnormalities in the sterilization process are detected. Purpose/Hypothesis The purpose of this study was to report increased infection rates after knee ligament reconstructions due to undetectable steriliza...

The evolution of orthopaedics has witnessed a pronounced shift from generalist practice to subspecialisation, a trend that has fundamentally reshaped the field over the past century. Originally, orthopaedic surgeons were trained to address a broad spectrum of musculoskeletal conditions. However, increasing complexity and specialization in knowledge...

Purpose This umbrella review aimed to identify, synthesise and critically appraise the findings of meta‐analyses that compare adverse events—rates of complications, reoperations and revisions—following total knee arthroplasty (TKA) using unrestricted kinematic alignment versus mechanical alignment. Methods Using the Preferred Reporting Items for S...

Purpose The purpose of this study was to predict high‐risk patients who experience significant increases in hospital charges and length of stay (LOS) following specific postoperative complications. Methods This study analyzed over two million patients from the Nationwide Inpatient Sample database undergoing elective total knee arthroplasty (TKA) f...

Background: Robotic-assisted unicompartmental arthroplasty (rUKA) is gradually gaining more popularity than its conventional counterpart (cUKA). Current studies are highly heterogenic in terms of methodology and the reported results; therefore, establishing the optimal recommendation for patients becomes less straightforward. For this reason, this...

Efforts to improve research standards in orthopaedics, sports medicine, physical therapy, and rehabilitation are ongoing. Rrehabilitation andomized Controlled Trials (RCTs) are widely regarded as the gold standard for the collection of primary data. Similarly, systematic reviews, due to their methodological rigor, have become the gold standard for...

Aims This multicentre retrospective observational study’s aims were to investigate whether there are differences in the occurrence of radiolucent lines (RLLs) following total knee arthroplasty (TKA) between the conventional Attune baseplate and its successor, the novel Attune S+, independent from other potentially influencing factors; and whether t...

Purpose To identify, synthesise and critically appraise findings of systematic reviews and meta‐analyses on pre‐ and post‐operative radiographic angles (lateral distal femoral angle [LDFA], medial proximal tibial angle [MPTA] and hip–knee–ankle [HKA] angle) of unrestricted kinematic alignment versus mechanical alignment in total knee arthroplasty (...

Purpose Posterior elongation of the physiological terminal sulcus (TS) due to lateral femoral condyle impaction fracture (LFC‐IF) after an anterior cruciate ligament (ACL) tear could potentially decrease the weight‐bearing area of the tibiofemoral joint, decrease the tension on lateral meniscus and cause flattening of the LFC which would influence...

Robotic‐assisted total knee arthroplasty (RTKA) has gained widespread acceptance due to its demonstrated ability to improve surgical accuracy compared to conventional total knee arthroplasty (CTKA). While the precise impact of RTKA on postoperative patient‐reported outcome measures (PROMs) remains inconclusive, the increased accuracy in alignment a...

Total knee arthroplasty (TKA) is on the verge of being revolutionized by artificial intelligence (AI), which will make it possible for robots to have a clinical influence in areas where navigation systems have been rendered ineffective. Navigation has been shown to increase surgical accuracy; nevertheless, it has not been shown to provide major gai...

Introduction Despite significant advancements in total knee arthroplasty (TKA), some patients require revision surgery (R‐TKA) due to complications such as infection, mechanical loosening, instability, periprosthetic fractures, and persistent pain. This study aimed to explore the specific causes leading to R‐TKA, associated complications, including...

This chapter aims to give an update and review of current evidence of manual and device-related cooling in patients undergoing total knee arthroplasty. Different cooling techniques are presented, and their pros and cons are discussed.

Patients after total knee arthroplasty (TKA) nowadays expect a pain-free, stable and well-functioning knee, including a good range of motion (ROM). However, the optimal ROM is not achieved in all patients. There is a considerable number of reasons for limited ROM after TKA. The most important one is the preoperative ROM, which is a good predictor o...

Stiffness after total knee arthroplasty (TKA) still poses a challenge to knee surgeons. Reduced range of motion (ROM) is associated with functional impairments, decreased patient satisfaction, and a lower overall quality of life [1]. It is important when discussing stiffness to correctly identify the underlying cause of it. Most often, adhesions, k...

Ecologically caring for Mother Earth is an increasingly important aspect of our everyday lives. Nowadays it should be a prerequisite and moreover a general principle for every part of our life. Like many other industrial and business sectors, hospitals generate large amount of waste and use a lot of energy, water, and other valuable resources to wo...

Diabetes mellitus (DM) represents an important risk factor after total joint arthroplasty (TJA) for both perioperative and long-term complications, in particular periprosthetic joint infection (PJI). The risk of complications appears to be correlated to uncontrolled perioperative hyperglycemia (blood glucose level >180 mg/dL). In diabetic patients...

An essential aspect of the philosophy of ‘Fast Track’ is the continuous drive for further improvement. Are we doing the best we can? Where can we improve further? Building on evidence and guidelines. We are creating a steady medical landscape that was stable for decades. Humans have been searching for permanent, long-lasting solutions for centuries...

Multiligament knee injuries (MLKIs) represent a broad spectrum of pathology with potentially devastating consequences. Currently, disagreement in the terminology, diagnosis and treatment of these injuries limits clinical care and research. This study aimed to develop consensus on the nomenclature, diagnosis, treatment and rehabilitation strategies...

Despite improvements in implant design, surgical techniques and assistive technologies for total knee arthroplasty (TKA), anterior knee pain (AKP) remains frequently reported, even by satisfied patients. This persistent problem calls for better understanding and management of the patellofemoral or anterior compartment during surgery, just as the te...

Purpose Establishing the diagnosis of loosening in total or unicondylar knee arthroplasty remains a challenge with different clinical and radiological signs evaluated in study designs with high risk of bias, where few or incomplete criteria are formulated for establishing the diagnosis of implant loosening. This study aimed at evaluating the variab...

Explorative data analysis (EDA) is a critical step in scientific projects, aiming to uncover valuable insights and patterns within data. Traditionally, EDA involves manual inspection, visualization, and various statistical methods. The advent of artificial intelligence (AI) and machine learning (ML) has the potential to improve EDA, offering more s...

Purpose The purpose of this systematic review was to compare patient satisfaction patient‐reported outcomes (PROMs) levels after mechanically aligned (MA) and kinematically aligned (KA) total knee arthroplasty (TKA). Methods A systematic literature search following PRISMA guidelines was conducted on PubMed, Embase, Medline and Scopus to identify p...

Purpose There is a lack of a clear, uniform definition for intraoperatively assessed component loosening of a knee arthroplasty component, complicating the interpretation and interchangeability of results of diagnostic studies using an intraoperative observation as the reference test. The purpose of this study was to establish a consensus among spe...

Purpose Patient dissatisfaction rates following total knee arthroplasty (TKA) reported in the literature reach 20%. The optimal coronal alignment is still under debate. The aim of this retrospective study was to compare clinical outcomes in different coronal plane alignment of the knee (CPAK) phenotypes undergoing mechanically aligned (MA) TKA. The...

Purpose For primary total knee arthroplasty (TKA), there is an increasing trend towards patient‐specific alignment strategies such as kinematic alignment (KA) and inverse kinematic alignment (iKA), which by restoring native joint mechanics may yield higher patient satisfaction rates. Second, the most recent Australian joint registry report describe...

Purpose The Knee Society Scoring System (KSS) is a frequently used outcome score which quantifies functional patients' outcomes before and after total knee arthroplasty (TKA). Several problems arise when trying to implement KSS for obtaining postoperative outcomes after more personalised aligned TKAs. Scoring for valgus femorotibial angle (FTA) int...

Artificial intelligence's (AI) accelerating progress demands rigorous evaluation standards to ensure safe, effective integration into healthcare's high‐stakes decisions. As AI increasingly enables prediction, analysis and judgement capabilities relevant to medicine, proper evaluation and interpretation are indispensable. Erroneous AI could endanger...

The collaboration of physical therapists and surgeons, including individual patients' perspectives, is key for a successful outcome—however, this is particularly underreported in many congresses, publications and clinical practice. Orthopaedic surgeons talk about surgery and physical therapists talk about physical therapy. Although enhanced teamwor...

Recent advances in artificial intelligence (AI) present a broad range of possibilities in medical research. However, orthopaedic researchers aiming to participate in research projects implementing AI‐based techniques require a sound understanding of the technical fundamentals of this rapidly developing field. Initial sections of this technical prim...

Purpose The present study focuses on testing the capability of a restricted tibia-first, gap-balanced patient-specific alignment technique (PSA) to restore bony morphology and phenotypes. Methods Three-hundred and sixty-seven patients were treated with navigated total knee arthroplasty and tibia-first gap-balanced PSA technique. Boundaries for med...

Background Alumina particles from the grit blasting of Ti-alloy stems are suspected to contribute to aseptic loosening. An alumina-reduced stem surface was hypothesized to improve osseointegration and show comparable short-term outcomes to those of a standard stem. Methods In this prospective, double-blind, randomized trial, 26 standard (STD) and...

Purpose To identify gender differences in (1) the coronal alignment of functional knee phenotypes and (2) the JLCA (joint line convergence angle) in relation to the phenotype classification. Methods This study is a retrospective data analysis, including 12,099 osteoarthritic knee computed tomography (5025 male, 7074 female) analysed by Medacta sof...

Background: A comprehensive exploration evaluating left-to-right knee symmetry across all anatomical planes utilizing three-dimensional (3D) scans stands absent from the existing body of research. Therefore, the primary objectives of this investigation involved examining potential differences and resemblances in alignment and structure between left...

Purpose One of the most pertinent questions in total knee arthroplasty (TKA) is: what could be considered normal coronal alignment? This study aims to define normal, neutral, deviant and aberrant coronal alignment using large data from a computed tomography (CT)‐scan database and previously published phenotypes. Methods Coronal alignment parameter...

Despite its potential advantages, unicondylar knee arthroplasty (UKA) is still rarely used compared to total knee arthroplasty (TKA). Higher patient satisfaction with UKA is generally offset by higher revision rates compared to TKA. The surgeon’s routine is of decisive importance for a successful outcome, particularly when performing UKA. Furthermo...

Although hip and knee joint replacements provide excellent clinical results, many patients still do not report the sensation and function of a natural joint. The perception that the joint is artificial may result from the anatomical modifications imposed by the surgical technique and the implant design. Moreover, the joint replacement material may...

Dissatisfaction following total knee arthroplasty (TKA) has been extensively documented and it was attributed to numerous factors. In recent years, significant focus has been directed towards implant alignment and stability as potential causes and solutions to this issue. Surgeons are now exploring a more personalized approach to TKA, recognizing t...

Artificial intelligence (AI) has the potential to transform medical research by improving disease diagnosis, clinical decision-making, and outcome prediction. Despite the rapid adoption of AI and machine learning (ML) in other domains and industry, deployment in medical research and clinical practice poses several challenges due to the inherent cha...

Isolated osteoarthritis (OA) of the lateral femorotibial compartment is considered to occur less often than that of the medial compartment. Analysis of knee joint replacement in Germany generally shows an increasing trend for unicompartmental knee arthroplasty (UKA). Indications for lateral unicompartmental knee arthroplasty are painful OA limited...

Effective communication within the realm of scientific publishing remains pivotal for the broad dissemination of research findings and new clinical insights to the global medical community. The integration of visual and textual elements has gained prominence as an instrumental means to facilitate comprehension and bridge cognitive divides across di...

Peer review is an essential process to ensure that scientific articles meet high standards of methodology, ethics and quality. The peer-review process is a part of the academic mission for physicians in the university setting. The work of reviewers is of great value for authors, as it gives constructive criticism and improves manuscript quality bef...

Purpose To investigate the correlation between postoperative limb/component alignments and clinical/functional outcomes following medial unicondylar knee arthroplasty (mUKA). Methods Inclusion criteria included peer‐reviewed English‐ or German‐language publications assessing postopera‐ tive limb or implant alignment and clinical outcomes of mUKA. M...

Introduction Many fixation methods are available for anterior cruciate ligament (ACL) grafts. Adjustable buttons (ABs) are characterized by their high fixation strength but have the disadvantage of potential stretching of their linking suture material. Press-fit bone plugs provide fixation at the joint line and enhance biological graft healing. Usi...

Purpose: External snapping hip syndrome (ESHS) was historically attributed to isolated iliotibial band (ITB) contracture. However, the gluteus maximus complex (GMC) may also be involved. This study aimed to intraoperatively identify the ESHS origin and assess the outcomes of endoscopic treatment based on the identified aetiological type. Methods:...

PurposeMesenchymal stem cells (MSC) are an attractive cell source for potential healing and regeneration of damaged tissue. This systematic review was initiated to detect safety and potential complications of the therapeutic use of MSCs for the treatment of osteoarthritis and cartilage defects of the knee joint.Methods The review was conducted in a...