Cone beam computed tomography (CBCT) – 3D diagnostics in orthopedics

What is CBCT?

Cone beam computed tomography is a 3D imaging method that works with a cone-shaped X-ray volume. During a short rotation of the device around the region to be examined, many individual projections are recorded and reconstructed into a high-resolution three-dimensional data set.

In contrast to classic multi-slice CT (fan beam CT), CBCT in orthopedics is particularly optimized for small to medium-sized examination areas (e.g. foot, ankle, hand, wrist, elbow, sometimes knee). A significant advantage is the fine spatial resolution of bony structures with often a lower radiation dose - depending on the question and the device. In addition, weight-bearing images (e.g. standing foot and ankle scans) are possible, which allows assessment under real everyday conditions.

• High-detail 3D imaging of bones
• Short examination time
• Often lower radiation dose than conventional CT for suitable questions
• Weight-bearing images possible (e.g. foot/ankle)

When is a CBCT useful? Indications

CBCT complements conventional X-rays and MRI in musculoskeletal diagnostics. We recommend it selectively when a 3D assessment of the bone structures is crucial - for example for surgical planning or to clarify unclear complaints with a possible bony cause.

• Occult or complex fractures (e.g. scaphoid, calcaneus, metatarsal, distal radius fracture)
• Misalignments and deformities of the foot under stress (e.g. hallux valgus, pes planovalgus/arch arches)
• Osteoarthritis assessment of small and medium-sized joints in 3D (e.g. ankle, tarsometatarsal joints, wrist)
• Osteochondral lesions in the ankle or knee joint (bony part)
• Postoperative control: implant and screw position, consolidation, suspected nonunion
• Bony impingement syndromes (e.g. bony impingements)
• Clarification of cystic bone lesions, sclerosis, bony extensions
• Planning joint-preserving or corrective interventions (e.g. osteotomies on the forefoot and hindfoot)

Important: Soft tissue structures such as ligaments, tendons, menisci or cartilage are only shown to a limited extent in CBCT. For these questions, MRI or ultrasound are usually superior.

Advantages and limitations of CBCT

• Advantages:
• Excellent bony detail resolution in 3D
• Weight-bearing images enable functional assessment
• Short examination times, high patient comfort
• In appropriate scenarios, lower radiation exposure than conventional CT
• Precise basis for surgical planning and postoperative controls

• Limits:
• Soft tissue visualization is limited – MRI/ultrasound is often superior
• Artifacts in metal can make local assessment difficult
• Not suitable for whole body diagnostics
• Ionizing radiation: only if there is a clear indication

We carefully weigh the benefits and potential risks and choose the procedure that best answers your question - conservatively oriented and based on the principle of as much diagnostics as necessary, as little radiation as possible.

Process of the investigation

The examination is painless. If you have difficulty standing or maintaining a position, we will find suitable storage.

Radiation protection & safety

CBCT uses X-rays. In many orthopedic issues, the dose is often lower compared to multi-slice CT, but remains an exposure. We work according to the ALARA principle (As Low As Reasonably Achievable) and prefer to use radiation-free procedures (e.g. ultrasound, MRI) if they adequately answer the diagnostic question.

• Individual choice of protocol (region, question, patient body type)
• Protection of sensitive regions, where technically sensible
• Particular restraint in children and young people
• During pregnancy only if strictly indicated and after informed consent

Please inform us in advance if you are pregnant, have known allergies to plasters/metal (for fixations) or if you cannot stand/sit still for a long time.

CBCT compared to X-ray, CT, MRI and ultrasound

• X-ray: Fast, available, low dose. 2D overlays can obscure details. CBCT provides 3D when X-rays are not enough.
• Conventional CT: Very powerful, especially a. for larger regions and complex soft tissue/bone issues. CBCT can be more dose-saving for small to medium-sized areas with bony issues.
• MRI: Best choice for cartilage, ligaments, menisci, tendons, bone marrow edema - without radiation. Complements CBCT for combined questions.
• Ultrasound: Dynamic, radiation-free, ideal for superficial soft tissues (tendons, bursa). No 3D bone representation like in CBCT.

We will advise you on which method offers the greatest added value for your situation - the combination of several methods is often crucial.

Which body regions do we examine with CBCT?

• Foot and forefoot: Hallux valgus, metatarsal joints, metatarsal fractures, sesamoid bones
• Hindfoot and ankle: osteoarthritis, osteochondral lesions (bony), impingement, heel bone
• Hand and wrist: scaphoid, distal radius, carpal instabilities (bony), osteoarthritis
• Elbow: Fractures, loose joint bodies (bony), bony deformities
• Selected knee questions (e.g. bony lesions, bony patella tracking) depending on the field of examination

Dental issues (e.g. jaw) are not the subject of our orthopedic CBCT diagnostics. For spinal issues, we use other procedures depending on the indication.

Quality standards & evaluation

Our diagnosis is structured according to orthopedic criteria with standardized measurements (e.g. angle analyzes for forefoot deformities). The data sets are archived in DICOM quality; Multiplanar reconstructions and 3D renderings support precise planning of conservative and - if necessary - surgical measures.

• Standardized protocols per region
• Comparison with previous recordings if available
• Interdisciplinary consultation for complex findings
• Transparent information about significance and limits

What happens after CBCT? Focus on conservative therapy

Imaging is not an end in itself. The aim is to treat your symptoms specifically and as gently as possible. Based on the CBCT findings, we primarily plan conservative measures and check whether additional diagnostics make sense.

• Individual physiotherapy and functional training
• Insoles and shoe supplies, orthoses, taping
• Stress and activity control in everyday life and sport
• Targeted infiltrations under ultrasound control (where appropriate)
• Accompanying laboratory diagnostics if inflammatory or metabolic contributions are suspected
• Surgical options only if there is a clear indication and after conservative options have been exhausted

We discuss the results in an understandable manner and work with you to determine the next step - comprehensibly, without time pressure.

Good to know: Common reasons not to undergo CBCT

• Pure soft tissue issues (e.g. ligament/tendon injuries) – MRI/ultrasound is usually superior here
• Missing indication if findings do not influence therapy
• Early pregnancy or unclear pregnancy – strict consideration is required
• Pronounced metal artifacts in the target area, which could significantly limit the informative value

Your CBCT appointment in Hamburg-Winterhude

You can find us at Dorotheenstraße 48, 22301 Hamburg. We make appointments after checking the indications - also in combination with a clinical examination and additional, radiation-free diagnostics (e.g. ultrasound).