In addition to evidence-based medicine at the current state of research, the patient is our focus. Our research specializes in the collection and evaluation of patient data after surgery. The patient’s perspective plays a central role in this. Certain information can only be provided by the patient and is important to us in verifying the quality of the treatment.
Our research projects are carried out in accordance with international guidelines and Swiss legislation and are partly carried out in cooperation with other clinics. You can find a selection of our current research projects here.

How are our Patients one Year after a Knee Replacement?

Since 2016 the knee team of the LEONARDO practice has been conducting a survey at several stages with all patients who have received a knee joint prosthesis. We currently have data from almost 300 patients from the first year after the operation.

The results are impressive: One year after the operation, 88% of the patients questioned were “very satisfied” or “satisfied” with their knee joint prosthesis. Almost all patients (95%) would have the operation performed again under the same circumstances. In addition, 87% of patients state that the condition of their knee joint is “very much better” or “significantly better” than before the operation.

Our patients’ functional ability also improved significantly in the first year with the “new” knee joint. The following diagram provides an overview:

The scale is from 0 to 100 points with higher values indicating better function.

The figure tells you, that knee function measured in different subscales clearly improved 4 months after the surgery and still increases over the next months. Likewise, the overall health state that not only refers to the knee could be improved.
The term “forgotten knee joint” means, that you are not aware of your artificial knee joint in everyday life. It indicates how normal your knee joint feels.

To collect so called „patient-reported outcome measures“ (PROMs) means some extra effort for us, especially as we are interested in long term results. This project is all the more important because it reflects the patient’s perspective and gives us valuable information about the success of therapy. The participation is of course voluntary. Approximately 80% of our patients agreed to complete 6 questionnaires in 5 years. The high number of participating patients gives even more importance to our very good results.

SKOOP Stable Knee withOut OPeration

A torn anterior cruciate ligament (ACL) can heal stably without surgery under certain circumstances. In this project, we are investigating the effectiveness of our treatment concept “SKOOP”. Treatment consists of conservative splint therapy and physiotherapy instead of surgery. Participating patients receive questionnaires at regular intervals by email and come for an MRI examination after 12 months. This is how we control the stable healing of the ACL. If it becomes apparent, during the course of treatment, that the ACL has not healed stably and that there is insufficient stability, surgical reconstruction of the ACL may be necessary.
We ask all appropriately qualifying patients in our practice, if they would like to participate in this project. Participation is of course voluntary. More information can be found here in the Participant information sheet (only German version available).

German Cartilage Registry

The Cartilage Register of the German Society for Orthopedics and Trauma Surgery is a web-based database which, using questionnaires, records data of patients (from Switzerland, Austria and Germany) with any cartilage damage.
Since 2013, anonymous data on cartilage surgery has been stored here and evaluated later. The goal is a scientific evaluation of the effectiveness and safety of such interventions. We have been certified as a recruitment center for the German Cartilage Registry since 2016 and ask all patients who we will treat, because of cartilage damage to the knee or ankle, if they want to participate in the registry. Participation is of course voluntary and does not affect the therapy. After you have given your consent, you will receive the questionnaires by email at regular intervals.
Further information: Link to Flyer and Homepage

Measuring the Alignment in Conformis iTotal Knee Replacements

Thanks to reconstruction in a 3D model, we can investigate exactly how the joint axis will be restored after a custom-made knee joint replacement (ConforMIS iTotal).
For this purpose, we ask all relevant patients whether they want to have an additional computed tomography (CT) performed 12 months after the operation. We require a total of 50 participants. Participation is voluntary and we will cover the additional costs. With the help of the CT images, a 3D model can be created, which helps us to determine the leg axis in detail. This project is funded by the RMS Foundation. You can find more information in our Participant information sheet (only German version available).

Poster Presentations

1 – 35. AGA Congress, September 2018
2 – 7. Annual Congress of the German Knee Society, November 2018
3 – Annual Congress Swissorthopaedics, September 2019



Vogel N, Kaelin R, Rychen T, Arnold MP. The German version of the High-Activity Arthroplasty Score is valid and reliable for patients after total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc. 2021 Mar 26. doi: 10.1007/s00167-021-06531-w. Epub ahead of print. PMID: 33770220. Link

Kaelin R, Rychen T, Vogel N, Mathis D, Arnold MP (2021) Restschmerz nach medial öffnender Tibiakopfosteotomie. Arthroskopie.

Tandogan RN, Kort NP, Ercin E, van Rooij F, Nover L, Saffarini M, Hirschmann MT, Becker R, Dejour D; European Knee Associates (EKA). Computer-assisted surgery and patient-specific instrumentation improve the accuracy of tibial baseplate rotation in total knee arthroplasty compared to conventional instrumentation: a systematic review and meta-analysis. Knee Surg Sports Traumatol Arthrosc. 2021 Mar 1. Link

Arnold MP, Calcei JG, Vogel N, Magnussen RA, Clatworthy M, Spalding T, Campbell JD, Bergfeld JA, Sherman SL; ACL Study Group. ACL Study Group survey reveals the evolution of anterior cruciate ligament reconstruction graft choice over the past three decades. Knee Surg Sports Traumatol Arthrosc. 2021 Jan 24. doi: 10.1007/s00167-021-06443-9. Epub ahead of print. PMID: 33486558. Link

Forster-Horváth C, Unterreithmeier U, Fries S, Ganal S, Gütler J, Vogel N, Herzog RF. Midterm Follow-Up and Assessment of Cartilage Thickness by Arthro-Magnetic Resonance Imaging After Arthroscopic Cam Resection, Labral Repair, and Rim Trimming Without Labral Detachment. Arthroscopy. 2021 Feb;37(2):541-551. doi: 10.1016/j.arthro.2020.10.012. Epub 2021 Jan 2. PMID: 33359757. Link


Vogel N, Rychen T, Kaelin R, Arnold MP (2020) Patient-reported outcome measures (PROMs) following knee arthroplasty: a prospective cohort study protocol. BMJ Open 10:e040811 Pdf

Corona K, Cerciello S, Vasso M, Toro G, Braile A, Arnold MP, Schiavone Panni A. Femoral component malrotation is not correlated with poor clinical outcomes after total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc. 2020 Dec;28(12):3879-3887. Link

Acevedo L, Iselin L, Berkelaar MHM, Salzmann GM, Wolf F, Feliciano S, Vogel N, Pagenstert G, Martin I, Pelttari K, Barbero A, Arnold MP. Comparison of Human Articular Cartilage Tissue and Chondrocytes Isolated from Peripheral versus Central Regions of Traumatic Lesions. Cartilage. 2020 Sep 22:1947603520958154. Link

Shamdasani S, Vogel N, Kaelin R, Kaim A, Arnold MP. Relevant changes of leg alignment after customised individually made bicompartmental knee arthroplasty due to overstuffing. Knee Surg Sports Traumatol Arthrosc. 2020 Sep 11. doi: 10.1007/s00167-020-06271-3. Epub ahead of print. Link

Skowronek P, Arnold M, Starke C, Bartyzel A, Moser LB, Hirschmann MT; European Knee Associates (EKA). Intra- and postoperative assessment of femoral component rotation in total knee arthroplasty: an EKA knee expert group clinical review. Knee Surg Sports Traumatol Arthrosc. 2020 Apr 30. Link

Schenk L, Bethge L, Hirschmann A, Berbig R, Lüthi U, Arnold MP, Hirschmann MT. Ongoing MRI remodeling 3-7 years after collagen meniscus implantation in stable knees. Knee Surg Sports Traumatol Arthrosc. 2020 Apr;28(4):1099-1104. Link


Haeni DL, Vogel N, Tamborrini G (2019) Ultraschalldiagnostik und Chirurgie der distalen Bizepssehne. Rheuma Schweiz

Haeni DL, Lafosse T, Haggerty C, Plath J, Kida Y, Sanchez-Brass M, Wolf F, Calvo E, Muller AM, Barbero A, Lafosse L (2019) Tissue on the Transferred Coracoid Graft After Latarjet Procedure: Histological and Morphological Findings. Am J Sports Med 47:704–712 Link

Foruria AM, Gutiérrez B, Cobos J, Haeni DL, Valencia M, Calvo E (2019) Most coronoid fractures and fracture-dislocations with no radial head involvement can be treated nonsurgically with elbow immobilization. J Shoulder Elbow Surg 28:1395–1405 Link


Meister M, Koch J, Amsler F, Arnold MP, Hirschmann MT (2018) ACL suturing using dynamic intraligamentary stabilisation showing good clinical outcome but a high reoperation rate: a retrospective independent study. Knee Surg Sports Traumatol Arthrosc 26:655–659 Link

Aramberri M, Tiso G, Haeni DL (2018) Arthroscopic and Endoscopic Technique for Subcoracoid Synovial Chondromatosis of the Shoulder Through a Medial Transpectoral Portal. Arthrosc Tech 7:e279–e283 Link

Opsomer GJ, Gupta A, Haeni DL, Schubert T, Lejeune E, Petkin K, Maharaj J, Lafosse L (2018) Arthroscopic Double-Layer Lasso Loop Technique to Repair Delaminated Rotator Cuff Tears. Arthrosc J Arthrosc Relat Surg Off Publ Arthrosc Assoc N Am Int Arthrosc Assoc 34:2943–2951 Link

Plath JE, Henderson DJH, Coquay J, Duck K, Haeni D, Lafosse L (2018) Does the Arthroscopic Latarjet Procedure Effectively Correct “Off-Track” Hill-Sachs Lesions? Am J Sports Med 46:72–78 Link

Niemeyer P, Becher C, Brucker PU, Buhs M, Fickert S, Gelse K, Günther D, Kaelin R, Kreuz P, Lützner J, Nehrer S, Madry H, Marlovits S, Mehl J, Ott H, Pietschmann M, Spahn G, Tischer T, Volz M, Walther M, Welsch G, Zellner J, Zinser W, Angele P (2018) [Significance of Matrix-augmented Bone Marrow Stimulation for Treatment of Cartilage Defects of the Knee: A Consensus Statement of the DGOU Working Group on Tissue Regeneration]. Z Orthopadie Unfallchirurgie 156:513–532 Link

Kaelin R, Christen B, Eggli S, Miozzari H, Arnold MP (2018) Behandlung degenerativer Meniskusläsionen. Swiss Med Forum EMH Media 18:147–153 Link

Mathis DT, Kaelin R, Rasch H, Arnold MP, Hirschmann MT (2018) Good clinical results but moderate osseointegration and defect filling of a cell-free multi-layered nano-composite scaffold for treatment of osteochondral lesions of the knee. Knee Surg Sports Traumatol Arthrosc 26:1273–1280 Link


Arnold MP, Burger LD, Wirz D, Goepfert B, Hirschmann MT (2017) The biomechanical strength of a hardware-free femoral press-fit method for ACL bone-tendon-bone graft fixation. Knee Surg Sports Traumatol Arthrosc 25:1234–1240 Link

Forster-Horvath C, Domb BG, Ashberg L, Herzog RF (2017) A Method for Capsular Management and Avoidance of Iatrogenic Instability: Minimally Invasive Capsulotomy in Hip Arthroscopy. Arthrosc Tech 6:e397–e400 Link


Arnold MP, Rychen T (2016) Knieprothetik nach Mass aus dem 3D-Drucker. Swiss Med Forum 16:702–6 Link

Forster-Horváth C, Artz N, Hassaballa MA, Robinson JR, Porteous AJ, Murray JR, Newman JH (2016) Survivorship and clinical outcome of the minimally invasive Uniglide medial fixed bearing, all-polyethylene tibia, unicompartmental knee arthroplasty at a mean follow-up of 7.3years. The Knee 23:981–986 Link

Forster-Horvath C, von Rotz N, Giordano BD, Domb BG (2016) Acetabular Labral Debridement/Segmental Resection Versus Reconstruction in the Comprehensive Treatment of Symptomatic Femoroacetabular Impingement: A Systematic Review. Arthrosc J Arthrosc Relat Surg 32:2401–2415 Link

Nourissat G, Neyton L, Metais P, Clavert P, Villain B, Haeni D, Walch G, Lafosse L (2016) Functional outcomes after open versus arthroscopic Latarjet procedure: A prospective comparative study. Orthop Traumatol Surg Res 102:S277-s279 Link

Horisberger M, Haeni D, Henninger HB, Valderrabano V, Barg A (2016) Total Arthroplasty of the Metatarsophalangeal Joint of the Hallux. Foot Ankle Int 37:755–765 Link