Metacarpal fractures (fractures of the metacarpal bones)

Quick overview

• Typical: Fall on the hand, hit against a hard surface (boxer fracture on metacarpal V), crush or torsion injury.
• Symptoms: Pain, swelling, tenderness over the affected bone, limited strength in the fist; sometimes misalignment.
• Diagnostics: Clinical examination including blood flow/nerve status, X-ray in two to three levels; for complex fractures close to the joint, CT if necessary.
• Therapy: Preferably conservative for stable, well-aligned fractures; Surgery for rotational errors, significant shortening/angulation, joint involvement, instability or open fractures.
• Healing: Bone healing usually takes 4-6 weeks; Full resilience and strength development take longer. Early function is key to avoid stiffness.

Anatomy and function of the metacarpal

The metacarpal consists of five tubular bones (metacarpals I–V). They connect the carpus with the metatarsophalangeal joints of the fingers. Each bone has a base (side near the carpus), shaft, neck and head (fingerward).

• Metacarpal I (thumb): special joint geometry for opposition; special fracture types at the base (e.g. Bennett, Rolando fracture).
• Metacarpals II–V: carry power when gripping and making fists; The axis of rotation must be precisely correct, otherwise fingers will cross when making a fist.

Tendons, ligaments and small hand muscles stabilize and move the metacarpals. Even minor axial or rotational errors can noticeably affect hand function.

Causes and risk factors

• Direct violence: hitting a hard object (often metacarpal V – “Boxer’s fracture”).
• Indirect violence: Fall on the hand or torsion when caught.
• Crush trauma: e.g. E.g. work accident, sports or traffic accident.
• Bone quality: Osteopenia/osteoporosis or vitamin D deficiency increase the risk of fractures.
• Smoking and poorly controlled diabetes: increased risk of delayed healing.

Symptoms

• Acute pain and swelling over the affected metacarpal bone.
• Pressure and tapping pain, limited fist closure, grip weakness.
• Malposition, step formation or shortening of the frog, hematoma.
• Rotation error: When making a fist, fingers cross or point past each other.
• Warning signs: Numbness, tingling, pale/cold fingers, open wound - seek medical advice immediately.

First aid

Diagnostics in practice

In our Hamburg practice, we take a structured anamnesis and examination with documentation of blood circulation, motor skills and sensitivity. Movement and pain tests help to assess accompanying injuries to ligaments or tendons.

• X-ray in two planes, oblique or strictly lateral if necessary, to assess the axis and joint involvement.
• CT for complex, intra-articular or multi-fragmentary fractures.
• For soft tissue problems, suspected tendon injuries or CRPS differential diagnosis: additional sonography/MRI in individual cases.

Wounds are checked for an open fracture. Open fractures require prompt surgical treatment with wound cleaning and stabilization.

Fracture types and assessment

When planning therapy, we consider localization, displacement and stability. Decisive parameters are angular position, rotation error, shortening and joint involvement.

• Location: base, shaft, neck (subcapital) and head fractures.
• Affected ray: thumb (I) vs. index to little finger (II-V).
• Fracture morphology: transverse, oblique, spiral, comminuted fracture (multi-fragmentary).
• Joint involvement: intra-articular with possible step formation.
• Soft tissue damage: closed vs. open, accompanying tendon/nerve injuries.

Rotational errors are hardly functionally tolerable and lead to crossing of the fingers. Certain angular deviations may be functionally acceptable, depending on the beam. If there is significant shortening or axial deviation, the risk of grip weakness and malunion increases.

Conservative treatment – ​​when it makes sense

Many metacarpal fractures can be safely treated without surgery if they are stable, sufficiently aligned and without rotational errors. The goal is pain-adapted, early functional therapy with reliable bone healing.

• Immobilization: functional thermoplastic splint or forearm plaster splint (e.g. ulnar splint for metacarpals IV/V).
• Duration: often 3–4 weeks until basic bony healing occurs; regular x-ray checks to check position.
• Pain therapy: gradual analgesia, cooling, elevation.
• Early function: early, guided movement exercises of the unaffected joints, later mobilization under guidance.
• Occupational therapy/physiotherapy: for edema control, mobilization, strength and coordination training.

Lifestyle factors influence healing: nicotine reduction, sufficient protein and vitamin D intake in the event of deficiencies, and good blood sugar control can support bone healing. Adjuvant stimulation procedures are discussed individually but are not standard.

Surgical procedures – indications and options

Surgery is considered if the fracture is unstable, there is a relevant misalignment, or the joint is affected. Open fractures and soft tissue damage also usually require surgical treatment.

• Indications: rotation error, significant shortening/angulation, intra-articular step formation, multi-fragment fracture, secondary dislocation under conservative therapy, open fracture.
• Procedure: closed reduction and Kirschner wire fixation (K-wires), intramedullary wire bundling (“bouquet”), screw osteosynthesis, miniplate osteosynthesis; rarely external fixator.
• Anesthesia: mostly regional anesthesia; Short procedures are often possible on an outpatient basis.
• Aftercare: depending on stability, early functional, temporary protection with a splint; Stitching and x-ray checks as per progress.

Specific fractures at the base of the thumb metacarpal (e.g. Bennett, Rolando fracture) require particularly precise reconstruction because the grip and opposition of the thumb are greatly affected.

We discuss benefits and risks transparently. There can be no guarantee of a specific result in medicine; We are guided by guidelines and current evidence.

Special case: “Boxer fracture” on the little finger

The subcapital fracture of the metacarpal V often occurs when the fist hits hard objects. It can be associated with a kink-shaped deformity.

• Conservative: often possible with an acceptable axis and no rotation errors; ulnar splint, early functional mobilization.
• Surgical: in cases of significant angulation, rotational error, shortening or instability; often K-wire or screw/plate fixation.
• Prognosis: mostly good; The decisive factors are correct axis, freedom of rotation and consistent aftercare.

Follow-up treatment and rehabilitation

Follow-up treatment depends on stability and pain. The goal is early, guided movement to avoid stiffness without endangering the fracture.

• Splint management: gradual wearing, pain-adapted reduction, early mobilization of free joints.
• Edema control: elevation, lymphatic drainage if necessary, active pumping exercises.
• Occupational/physical therapy: joint mobilization, tendon gliding, grip strength building, scar care after surgery.
• Stress build-up: progression adapted to everyday life, individually tailored to your job and sport.
• Ability to work: office work often possible earlier; Manual work requires longer protection times.

Possible complications

• Malunion (axis deviation, rotation error, shortening) with loss of strength or function.
• Restriction of movement/stiffness, tendon adhesions.
• Pain syndrome (CRPS) – rare; Recognize early and treat in an interdisciplinary manner.
• Pseudarthrosis (failure of bone healing), especially in cases of instability or risk factors.
• Infection after surgery, in rare cases osteomyelitis.
• nerve irritation or injury; very rarely compartment syndrome.

Close follow-up and early functional therapy help to minimize risks. If warning signs such as increasing pain, fever, redness or numbness occur, you should be checked by a doctor promptly.

Healing process, everyday life, sport

• Bone healing: often within 4-6 weeks.
• Building strength: several weeks to a few months, depending on the type of fracture and therapy.
• Sports: low-contact sports are often possible after medical clearance and a protective splint; Contact sports and martial arts later.
• Occupation: Writing/office work, some early on with a splint; heavy manual work later, gradually.
• Goal: pain-free, stable hand with good mobility and grip strength - but a guarantee is not possible.

Prevention and personal measures

• Protective gloves and safe technology for work and sport.
• Optimize bone metabolism: Check vitamin D status for risk profile, balanced diet.
• Quitting smoking supports bone healing.
• Consistent follow-up treatment and home exercises according to instructions to prevent stiffness.

When should you see a doctor?

• After a fall, blow or crush trauma with persistent pain/swelling.
• If there is a visible misalignment or restricted fist closure.
• For numbness, paleness/coldness of the fingers or open wounds (urgent).
• If pain increases or mobility becomes worse despite the splint.

Your treatment in Hamburg-Winterhude

In our orthopedic practice at Dorotheenstrasse 48, 22301 Hamburg, we accompany you from the diagnosis through the individually tailored therapy to the return to everyday life and work. We follow current guidelines and value conservative, function-oriented treatment - and discuss surgical options transparently if they are medically necessary and sensible.