Distal ulnar fracture

What is a Distal Ulnar Fracture?

A distal ulnar fracture is a break on the ulna side of the wrist. Anatomically, a distinction is made between fractures of the ulnar head, the ulnar neck and the ulnar tip (ulnar styloid). The latter is the most common form, often in combination with a distal radius fracture. What is clinically important is whether the stability of the distal radioulnar joint (DRUJ) and the triangular fibrocartilage complex (TFCC) is impaired - these structures control the rotational movement of the forearm and hand.

• Isolated ulnar styloid fracture (tip/apical vs. near base)
• Fracture of the ulnar neck or ulnar head (metaphyseal/intraarticular)
• Combination with distal radius fracture (most common constellation)

Anatomy: Ulna, DRUJ and TFCC

The ulna, together with the radius, forms the forearm skeleton. At the end of the wrist, the ulnar head and sigmoid notch of the radius form the distal radioulnar joint (DRUJ). This enables the rotational movements of pronation and supination. The unit is stabilized by the triangular fibrocartilage complex (TFCC) and ligamentous structures that attach to the base of the ulnar styloid.

• Ulnar styloid: bony process, attachment point of important ligaments of the TFCC
• Ulnar head/neck: involved in the articular surface of the DRUJ
• TFCC: Fibrocartilage ligament complex, central to stability and load transfer

Significance for therapy: Fractures near the ulnar styloid base or the ulnar head can jeopardize DRUJ stability and require particularly careful assessment.

Causes and risk factors

A typical trigger is a fall onto an outstretched hand. Depending on the direction of force, bone density and accompanying injuries, simple, non-displaced fractures or complex, displaced fractures occur.

• Falling from standing height (common in osteoporosis)
• Sports accidents (e.g. cycling, skiing, board sports)
• Traffic accidents or direct impact trauma
• Favorable: osteoporosis, smoking, vitamin D deficiency, repeated falls

Symptoms and warning signs

Typical complaints include ulnar-side wrist pain, swelling and tenderness over the ulnar head or ulnar styloid. Rotating movements (doorknob, opening bottle) are painful. If the DRUJ is unstable, the wrist and forearm appear “wobbly” or weak.

• Pain and swelling on the ulnar side of the wrist
• Loss of movement and strength, especially during rotational movements
• Crepitation (rubbing noise), misalignment in displaced fractures
• Numbness or tingling (rare, indicating nerve involvement)

Warning signs that require prompt medical evaluation: open wounds, circulatory or sensory disorders, severe misalignment or increasing pain despite immobilization.

First aid: what to do after a fall?

Diagnostics in practice

After the history and clinical examination, standardized x-rays of the wrist are taken in two planes. A real side view is important to assess DRUJ congruence. For complex fractures or unclear joint involvement, we add imaging.

• X-ray wrist/forearm (2 levels, additional images if necessary)
• CT for intra-articular or complex fractures for surgical planning
• MRI if TFCC lesion or ligamentous instability is suspected
• Examination of DRUJ stability (e.g. ballottement test) – if possible due to pain

The important distinction is: stable, non-displaced fracture (usually conservative) versus displaced or DRUJ-unstable fracture (possibly surgical).

Classification and special forms

The classification helps to assess the risk of instability and subsequent problems. The location of the fracture line in relation to the TFCC starting points is particularly relevant.

• Ulnar styloid fracture: apical (tip) usually stable; basal fracture may involve TFCC approach.
• Ulnar neck/ulnar head: metaphyseal or intra-articular – higher risk of DRUJ incongruence.
• Open fractures: require rapid surgical treatment.
• Children: epiphyseal injuries (growth plate) and greenstick fractures possible.

Conservative treatment: the first step

Stable, non-displaced distal ulnar fractures – particularly apical ulnar styloid fractures – can often be successfully treated without surgery. The priority is pain-free immobilization and early functional mobilization within a safe framework.

• Immobilization: Forearm cast splint or removable forearm wrist splint, usually 3-6 weeks depending on the fracture and control.
• Pain management: depending on tolerability, as short-term and targeted as possible.
• Swelling management: elevation, cucifix/sling if necessary, manual lymphatic drainage if swelling is severe.
• Movement: early finger and shoulder movements; after release, gradual DRUJ mobilization.
• Physio/occupational therapy: Instructions for safe mobilization, scar/soft tissue care, strength building.
• Everyday life: temporarily no stressful rotational movements; Household and screen activities adjusted.

Regular x-ray checks ensure that no secondary dislocation occurs. If instability persists or the misalignment increases, we re-evaluate the treatment options.

Surgical treatment – ​​why and when?

Surgery may make sense if the joint position or stability cannot be adequately secured conservatively. Open fractures, relevant steps in the joint or pronounced misalignments are also reasons for surgical stabilization.

• Indications: DRUJ instability, basal ulnar styloid fracture with TFCC involvement, displaced ulnar head/neck fracture, open fracture, combined complex radius/ulna fracture.
• Procedure: screw osteosynthesis, Kirschner wires, tension straps, angle-stable miniplates - individually depending on the fracture type.
• Accompanying measures: in the case of combined injuries, treatment of the distal radius fracture; If necessary, TFCC fixation/suture.
• Goal: anatomical alignment, stable DRUJ function, early safe mobilization.

Before each operation, careful information, benefit-risk assessment and individual planning are carried out. We also discuss alternatives and the expected course - binding promises of healing are not medically serious.

Rehabilitation and healing process

Depending on the type of fracture, bony healing usually takes 6-8 weeks, and longer for complex fractures. Functional recovery – particularly rotational movements and grip strength – can take 3-4 months.

• Return to office/desk work is often possible after 1-2 weeks (individual).
• Manual activities and sports, depending on the healing process, should take place after 8-12 weeks at the earliest.
• Stopping smoking, adequate protein and vitamin D/calcium intake support bone healing.

Possible complications and long-term consequences

Complications are rare but possible. Early detection and treatment improves the prognosis.

• Pseudarthrosis (lack of bony healing), delayed fracture healing
• Malposition/malunion with painful DRUJ incongruence
• Persistent DRUJ instability or TFCC complaints
• Irritation of tendons/soft tissues, implant irritation
• Nerve irritation, rarely CRPS (Complex Regional Pain Syndrome)
• Infection (especially in open fractures or after surgery)

If pain on the ulnar side persists after a radius fracture has healed, we specifically check the ulna, the DRUJ and the TFCC. If appropriate, imaging or corrective procedures should be considered.

Special features for children and older patients

Greenstick fractures and injuries to the growth plate are possible in children. Gentle immobilization with close control is often sufficient. Operations are exceptions and are strictly indexed. In older age, osteoporosis and fall prevention are of primary importance.

• Children: good remodeling tendency, but pay attention to the axis and DRUJ function.
• Older people: osteoporosis assessment (e.g. DXA), reduce risk of falls, check aids.
• Review medications (e.g., anticoagulation) and address wound healing risks.

Prevention and self-help

• Fall prevention: non-slip shoes, securing the living area, gait/balance training.
• Osteoporosis screening and therapy according to guidelines.
• Sport: wrist-friendly technology, protectors depending on the discipline.
• Ergonomic adjustments at the workplace, breaks and mobilization exercises.

Your treatment in Hamburg

In our orthopedic specialist practice at Dorotheenstrasse 48, 22301 Hamburg, we clarify distal ulnar fractures in a structured manner - with a focus on conservative, function-preserving therapy. If an operation is medically necessary, we will explain the procedure transparently and accompany you through the rehabilitation. You can receive appointments flexibly online via Doctolib or by email.