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 high energy transfer required to fracture the diaphyseal section of both bones of the forearm direct trauma direct blow to forearm indirect trauma (high-energy bending moments) motor vehicle accidents falls from height axial load applied to the forearm through the hand sports injuries low-energy diaphyseal radius and ulna fractures should raise suspicion for injuries to the wrist and elbow. 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 History handedness occupational and hobby hand dependence Symptoms pain and swelling loss of forearm and hand function Physical exam inspection gross deformity open injuries check for tense forearm compartments examine the soft-tissue envelope 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 contralateral fiims may assist in surgical planning 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 in patients > 10 year of age 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 patients 10 year or older are 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 prevention after plate removal wear functional forearm brace for 6 weeks and protect activity for 3 months after plate removal treatment revision ORIF +/- bone graft 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