for orthopedics



now also available online!

Welcome to ONZ
your orthopedic-neurosurgical practice group

Since 1989, we have been offering our patients a wide range of conventional therapies as well as state-of-the-art surgical procedures. With our medical care centers and practices in Datteln, Recklinghausen, Kamen, Unna and Dortmund, we ensure medical care for our patients in the region. Thanks to our medical expertise and coherent care concepts, we also welcome many hundreds of patients from Australia, New Zealand, Canada or the USA every year.

Extensive patient education and the identification of suitable therapy options are very important to us and form the basis for developing your individual therapy plan together with you.

Your team at ONZ

We support you!

Hotline & Onlineservice

Location phone numbers

Our telephone center is available from 7:00 am – 4:00 pm. Please note that there may be waiting times due to increased call volumes.


Alternatively, you can simply send us your request via our contact form.

Consultations Hours

our consulting hours from monday till friday

from 8:00 am – 4:00 pm

In order to provide you with the best possible care, our consultation hours are appointment-based. If it is an emergency, please refer to the menu sub-item „Emergency consultation/without appointment“.

second medical opinon

You have been advised an orthopedic or neurosurgical operation and you would like to have this checked again by another specialist? Or you need a medical expertise?

Please indicate this when you contact us, so that we can process your request quickly and to your satisfaction.

Emergency consultation

Acute pain and emergencies cannot be planned! Therefore, the ONZ medical team offers emergency consultation hours at all locations.

The emergency consultation takes place daily in all practices from Mondays to Fridays between 11:00 and 12:00. Since our capacities are are limited, we kindly ask you to call us in advance or to book an acute of an acute appointment in our online calendar.

Emergency consultation hours will change as of 01/01/2022.

09:00 AM – 09:45 AM
01:30 PM – 02:15 PM


The Specialists.

Our strength is fast and very accurate diagnostics through the connection and exchange of the specialties of orthopedics and neurosurgery. The physicians of the ONZ have particular specializations and additional qualifications and use these in a constant dialogue.

Dr. Maximilian Timpte

In ONZ a sought-after specialist in diseases of the shoulder joint, hip and knee.
Make appointment

Dr. Guido Ostermann

Specialist in neurosurgery and expert in conservative, minimally invasive and surgical treatment of chronic pain of the cervical and lumbar spine.
Make appointment

Assoc. Prof.
Dr. Wolfram Steens

Dr. Steens is a sought-after specialist for disorders of the hip, knee and ankle. He is a certified cartilage specialist.
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Dr. Thomas Bierstedt

Dr. Thomas Bierstedt is a specialist in neurosurgery and an expert in the conservative and surgical treatment of degenerative and traumatic spinal disorders.
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Dr. Bernd Illerhaus

Specialist in neurosurgery, spine surgery, manual medicine/chirotherapy and expert in conservative and minimally invasive endoscopic and surgical treatment of degenerative and traumatic spinal diseases.
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Dr. Jan Ahrens

Dr. Ahrens specializes in the surgical treatment of all major human joints. His surgical focus is on joint-retaining operations, including cartilage surgery, endoprosthetics and revision endoprosthetics.
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Dr. Bernard Neuhaus

Dr. Neuhaus is a proven specialist in foot and ankle disorders of children and adults. His surgical focus is on foot and ankle surgery, shoulder and knee surgery including cartilage surgery.
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Dr. Michael Preuhs

Dr. med. Michael Preuhs is a specialist in orthopedics with additional qualifications in sports medicine, chiropractic and acupuncture.
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Dr. Jakob Roberg

Dr. Roberg is a specialist in spine surgery and an expert in the surgical treatment of cervical and lumbar spine disorders.
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Heiko Schmidt

Is a specialist in minimally invasive, muscle-sparing hip arthroplasty as well as knee arthroplasty. Another focus is in the field of conservative as well as surgical and joint-preserving therapy of the upper as well as lower extremities, with shoulder, hip, knee, ankle and foot pathologies as well as in the field of cartilage and tendon surgery in adults and children.
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Ivo Fusek

Specialist in neurosurgery, spine surgery and expert in conservative and minimally invasive surgical treatment of degenerative and traumatic spine diseases, as well as neuromodulatory interventions for pain and spasticity therapy.
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Faculties and treatments

The ONZ treatment spectrum results from the particular specializations as well as special qualifications of our top physicians and reaches from all conventional therapies to the most modern minimally invasive procedures. We would like to present some of these treatments to you here.
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Im centr-o-med
Heibeckstr. 30
45711 Datteln
Call 02363-36690


Im Elisabeth Krankenhaus
Röntgenstr. 10
45661 Recklinghausen
Call 02361-302380


Pariser Bogen 7
44269 Dortmund
Call 0231-438906600


Westenmauer 45
59174 Kamen
Call 02307-2102789