SUMMARY

• Radius and ulnar shaft fractures, also known as adult both bone forearm fractures, are common fractures of the forearm caused by either direct trauma or indirect trauma (fall).

• Diagnosis is made by physical exam and plain orthogonal radiographs.

• Treatment is generally surgical open reduction and internal fixation with compression plating of both the ulna and radius fractures.

EPIDEMIOLOGY

• Demographics

  • highest incidence in

    • men between 10 and 20 years old

    • women over 60 years old

ETIOLOGY

• Pathophysiology

  • mechanism of injury

    • direct trauma

      • direct blow to forearm

    • indirect trauma

      • motor vehicle accidents

      • falls from height

        • axial load applied to the forearm through the hand

      • sports injuries

• Associated conditions

  • elbow and DRUJ injuries

    • Galeazzi fractures 

    • Monteggia fractures 

    • Essex-Lopresti injuries

  • compartment syndrome

    • evaluate compartment pressures if concern for compartment syndrome

ANATOMY

• Osteology

  • axis of rotation of forearm runs through radial head (proximal) and ulna fovea (distal)

    • distal radius effectively rotates around the distal ulna in pronosupination

  • radial bow accommodates rotation

    • radial bow is complex and not just in coronal or sagittal plane

    • maximal radial bow in the coronal plane is about 15mm at 60% distally along the radius

  • the ulna has a slight bow along the distal 75% of the shaft

• Ligaments

  • Interosseous membrane (IOM)

    • occupies the space between the radius and ulna

      • permits rotation of the radius around the ulna

      • connects the radius and ulna obliquely

      • axial load through the forearm begins in the distal radius and then transferred to the proximal ulna

      • distal fibers have the most tension in supination

      • the central fibers are under the most tension in a neutral position

    • comprised of 5 ligaments 

        

      • central band is key portion of IOM to be reconstructed

      • accessory band

      • distal oblique bundle

      • proximal oblique cord

      • dorsal oblique accessory cord

• Nerves

  • median nerve 

    • runs with the brachial artery and then courses between the heads of the pronator teres

    • then courses between the FDS and FDP until the carpal tunnel

  • ulnar nerve

    • in the forearm, begins between the heads of the FCU

    • then innervates the FDP to the ring and small fingers

    • divides into the motor and sensory branches in the hand 

  • radial nerve

    • splits into the superficial branch and the PIN

    • the superficial branch runs along the deep fascia to the brachioradialis

    • PIN

      • runs around the radial neck and through the supinator

      • then runs along the posterior interosseous membrane terminating in the wrist capsule beneath the 4th extensor compartment

• Vasculature

  • the brachial artery branches into the radial and ulnar arteries 1cm past the elbow joint

  • the radial artery is adherent to the FCRL

CLASSIFICATION

• Anatomic / Descriptive

  • closed versus open

  • location

  • comminuted, segmental, multi-fragmented

  • displacement

  • angulation

  • rotational alignment

• OTA classification

  • radial and ulna diaphyseal fractures

    • Type A (simple) 

      • simple fracture that is spiral (A1), oblique (A2), or transverse (A3)

    • Type B (wedge) 

      • wedge fracture that is intact (B2) or fragmentary (B3)

    • Type C (multifragmentary) 

      • multifragmentary fracture that is intact segmental (C2) or fragmentary segmental (C3)

PRESENTATION

• Symptoms

  • pain and swelling

  • loss of forearm and hand function

• Physical exam

  • inspection

    • gross deformity

    • open injuries

    • check for tense forearm compartments

  • vascular

    • assess radial and ulnar pulses

  • neuro

    • document median, radial, and ulnar nerve function

  • provocative tests

    • pain with passive stretch of fingers

      • alert to impending or present compartment syndrome

IMAGING

• Radiographs

  • recommended views

    • AP and lateral views of the forearm 

  • additional views

    • oblique forearm views for further fracture definition

    • ipsilateral AP and lateral of the wrist and elbow

      • to evaluate for associated fractures or dislocation

      • radial head must be aligned with the capitulum on all views

• CT

  • indications

    • rarely needed

    • may be helpful for possible occult fractures, evaluating intraarticular extension, or complex fracture characteristics

TREATMENT

• Nonoperative

  • closed reduction and immobilization

    • indications

      • rare

        • completely nondisplaced fractures in patients who are not surgical candidates

    • techniques

      • bracing

        • functional fracture brace

      • casting

        • Muenster cast with good interosseous mold 

    • outcomes

      • loss of >50 degrees of rotation in 30% of patients

      • high rates of non-union associated with non-operative management

• Operative

  • closed reduction and external fixation (ExFix)

    • indications

      • severe soft tissue injury (Gustilo IIIB)

  • open reduction internal fixation (ORIF) 

    • indications

      • nearly all both bone fractures in surgical candidates 

         

      • Gustilo I, II, and IIIa open fractures may be treated with primary ORIF 

         

    • outcomes

      • goal is for cortical opposition, compression, and restoration of forearm anatomy

      • most important variable in functional outcome is to restore the radial bow 

          

      • > 95% union rates of simple both bone fractures with compression plating

      • up to 88% union in comminuted fractures treated with bridge plating

  • open reduction internal fixation (ORIF) + bone grafting

    • indications

      • open fractures with significant bone loss

      • bone loss that is segmental or associated with open injury (primary or delayed grafting in open injuries) 

         

      • nonunions of the forearm

    • outcomes

      • use of autograft may be critical to achieving fracture union

  • closed reduction and intramedullary fixation (IMN)

    • indications

      • very poor soft-tissue integrity

    • outcomes

      • not preferred due to lack of rotational and axial stability and difficulty maintaining radial bow 

      • high nonunion rate

        • IMN does not provide compression across fracture site

TECHNIQUES

• Closed reduction and immobilization

  • technique

    • functional brace or Muenster cast

    • cast/brace should extend just above elbow to control forearm rotation

      • monitor very closely (~1 week) for displacement

      • should be worn for at least 6 weeks

• External fixation (ExFix) 

  • technique

    • 2nd and 3rd metacarpal shafts can both be utilized for distal pin placement

    • pin diameter should not exceed 4 mm

• Open reduction internal fixation (ORIF) 

  • approach

    • fixation of the fracture with less comminution restores length and may facilitate reduction of other bone

      • typically the radius is fixed first

    • usually performed through separate approaches due to risk of synostosis 

       

      • radius

        • volar (Henry) approach to radius 

          • best for distal 1/3 and middle 1/3 radial fractures 

             

        • dorsal (Thompson) approach to radius 

          • can be utilized for proximal 1/3 radial fractures

      • ulna

        • subcutaneous approach to ulna shaft 

  • technique

    • 3.5 mm DCP plate (AO technique) is standard 

        

      • 4.5 plates no longer used due to increased rate of refracture following removal

      • stiff 2.7mm locking plates may be used, but smaller recon plates should not be used

    • stainless steel plates provide greater bending rigidity than titanium

    • longer plates are preferred due to high torsional stress in forearm

      • may require contouring of plate

    • compression mode preferred to achieve anatomic primary bony healing

      • to minimize strain, six cortices proximal and distal to fracture should be engaged

    • locked plates are increasingly indicated over conventional plates in osteoporotic bone

    • bridge plating may be used in extensively comminuted fractures 

       

    • interfragmentary lag screws (2.0 or 2.7 screws) if necessary

    • open fractures

      • irrigation and debridement should be performed to remove any contaminated tissue or bony fragments without soft tissue attachments

    • plate placement

      • placement of plates on dorsal (tension) side is biomechanically superior but volar placement offers better place seating and soft tissue coverage

  • postoperative care

    • early ROM unless there is an injury to proximal or distal joint

    • should be managed with a period of non-weight bearing due to risk of secondary displacement of the fracture 

       

      • generally 6 weeks

    • clinical healing typically occurs at 3 months

• Open reduction internal fixation (ORIF) + bone grafting

  • technique

    • cancellous autograft is indicated in radial and ulnar fractures with significant bone loss 

       

    • vascularized fibula grafts can be used for large defects and have a lower rate of infection 

       

    • Masquelet technique (induced-membrane technique) can also be utilized in cases of non-union or open fractures with significant bone loss

      • 2 stage technique

        • 1st stage: I&D, cement spacer, and temporizing fixation 

        • 2nd stage: placement of bone graft into induced membrane and definitive fixation 

• Closed reduction and intramedullary Fixation (IMN)

  • approach

    • ulnar nail

      • inserted through the posterior olecranon

    • radial nail

      • inserted between the extensor tendons near Listers tubercle

  • technique

    • nails may need to be bent to accommodate for the radial bow

    • may use a small incision at fracture site to facilitate passing of nail

COMPLICATIONS

• Synostosis and Stiffness  

  • incidence

    • reported between 3 to 9%

  • risk factors

    • associated with ORIF using a single-incision approach

  • treatment

    • heterotopic bone excision can be performed with low recurrence risk as early as 4-6 months post-injury when prophylactic radiation therapy and/or indomethacin are used postoperatively 

       

• Surgical Site Infection (SSI)

  • incidence

    • 3% incidence with ORIF

  • risk factors

    • open fractures

• Compartment syndrome

  • incidence

    • about 1% overall

    • up to 15% depending on mechanism and fracture characteristics

  • risk factors

    • high energy crush injury

    • open fractures

    • low-velocity GSWs

    • vascular injuries

    • coagulopathies (DIC)

  • treatment 

    • fasciotomy

      • release of the superficial volar compartment alone may be adequate because the compartments are connected

      • other structures that may be released include: the mobile wad fascia, lacerates fibrosus, extensor compartment, deep volar compartment, and carpal tunnel

• Nonunion

  • incidence

    • < 5% after compression plating

    • up to 12% in extensively comminuted fractures treated with bridge plating

  • risk factors

    • extensive comminution

    • poorly applied plate fixation

    • IMN fixation

  • treatment

    • atrophic nonunions can be treated with 3.5 mm plates and autogenous cancellous bone grafting 

       

    • hypertrophic nonunions can be treated by increasing fixation

    • Infection and atrophic nonunions can also be treated with the Masquelet technique 

       

• Malunion

  • risk factors

    • direct correlation between restoration of radial bow and functional outcome

• Nerve injury

  • risk factors

    • PIN injury with Monteggia fractures and Henry (volar) approach to middle and upper third radial diaphysis

    • median nerve may be injured in the modified Henry approach

    • cutaneous branch of the ulnar nerve is at risk during the approach to the ulna

    • Type III open fractures

  • treatment

    • observe for three months to see if nerve function returns

      • explore if no return of function after 3 months

• Refracture 

   

  • incidence

    • up to 10% with early removal

  • risk factors

    • removing plate too early 

      • plates should not be removed < 1 year from implantation

    • large plates (4.5 mm)

    • comminuted fractures

    • persistent radiographic lucency

  • treatment

    • wear functional forearm brace for 6 weeks and protect activity for 3 months after plate removal

PROGNOSIS

• Overall, good subjective results, but with expected losses in ROM and strength

  • expected losses

    • reduced strength in grip (25% lost), pronation and supination (30% lost), wrist flexion (16% lost), and wrist extension (37% lost)

    • mild expected reduction (<10 deg) in pronation, supination, wrist flexion, and wrist extension

• Functional results depend on the restoration of radial bow 

    

  • malunion of the radius and ulna with angulation > 20 degrees is likely to limit forearm rotation