Distal Radius Fractures

Introduction 

• Distal radius Fractures are one of the most common Fractures encountered by Orthopedic Surgeon worldwide. 
•  PETIT  1st said these injuries as Fractures rather dislocation. 
• POUTEAU recognized injuries to the wrist from fall onto outstretched hand.
• ABRAHAM COLLES described these Fractures one and half inch above the carpal extremity of the radius. 
• MALGAIGNE in 1847 stated these injuries caused due to fall on the palm of hand.  He identified extra- and intra- articular fractures. 
• JOHN RHEA BARTON described subluxation of the wrist after fracture through distal articular surface of radius. 
• Robert Smith described fracture of distal radius with lower fragment displaced forward. 

Epidemiology 

• Females > males ( 2:1 )
• AGE - in females = common in their 6th decade                                                                               males = common in their 4th decade
• Low energy injuries ( 70%) > high energy injuries (10%) 
• Majority of Fractures ( ~ 60%)  are extra articular (AO type A), 10% are partial articular (AO type B), 30% are completely articular (AO type C)

Risk factors 

• Low BMD (Bone mineral density).
• Increasing falls especially with aging is a significant risk factor. 

Injury Mechanism 

• Fall onto outstretched hand from standing height mainly , small proportion of patients have high velocity injury. 
• Distal radius # resulted if angle at which forearm strike the ground was between 60 and 90 degrees with ulnar deviation resulting in radial styloid # and radial deviation results in ulnar styloid # .
• Frykman concluded clinical types of distal radius # occur when dorsiflexion of the wrist was between 40 and 90 degrees. If more then a carpal bone # and if less a proximal forearm # resulted .
• Fernandez divided distal radius Fractures based on the mechanism of injury. 

Associated Injuries with Distal radius and Ulna Fractures 

1. TFCC ( Triangular FibroCartilage Complex ) INJURY- more common than interosseous ligament injury,  reported in 39% to 82% of cases. 

• Majority are peripheral avulsions and may be associated with ulnar styloid # , the presence of which increases the risk of TFCC tear by a factor of ~ 5.

     2. INTEROSSEOUS LIGAMENT INJURY- predominantly  Scapholunate and      Lunatotriquetral injury.  

•  Geissler graded these injuries  Arthroscopically , Grade 1 being least severe with only attenuation or hemorrhage  and Grade 4 is gross instability with sufficient disruption. 
• Diagnosis of ligament injury can be done with Static radiographs of the distal radius in the more severe cases but diagnosis can be difficult with a distal radius # .
• Arthroscopy is probably the best method , another method is Carpal stretch test in which traction is applied to the wrist to emphasize disruption of Gilula's lines.
• There is increased risk of interosseous ligament injury , been demonstrated when there is more than 2 mm of positive ulnar variance and in intra-articular fractures.

SIGNS AND SYMPTOMS 

• Pain and swelling around the wrist .
• Visible Deformity in cases of displacement. 
• Any paresthesia or numbness in the fingers to rule out any median or ulnar nerve injury. 
• Pain elsewhere in the limb suggest ipsilateral injury.
• The classical dinner fork or silver fork deformity is due to dorsal displacement of the carpus secondary to dorsal angulation of the distal radius. 
• The reverse deformity is seen in volar displaced fractures. 
• The hand may be radially deviated and if  shortening of the radius the ulna will be prominent.
• Skin inspection to rule out any open wounds, common on ulnar side.
• Palpation of the fracture will elicit tenderness. 
• Thorough neurological testing of the hand should be done as acute carpal tunnel syndrome (CTS) may require prompt treatment. 

NORMAL RADIOLOGICAL PARAMETERS OF DISTAL RADIUS AND ULNA -

DISTAL RADIUS # 

 Parameters to check in Distal radius # 

1.  Radial length
2. Radial inclination 
3. Ulnar variance
4. Carpal malalignment         

   

   Carpal malalignment 

5. Tear drop angle 
   
6. A-P distance 
   

CLASSIFICATION-

FERNANDEZ CLASSIFICATION-

DRUJ INJURY CLASSIFICATION-

AO TRAUMA CLASSIFICATION-

A- Extraarticular 

B- Partial Articular 

C- Complete Articular

MANAGEMENT- 

1) Undisplaced distal radius fracture-

2) Displaced distal radius fracture-

Type of Cast.  The initial cast is usually a Below elbow Slab or Sugar tong splint. These  allow for swelling to occur in the cast.

REDUCTION MANEUVER 

The  recommended  position  of  immobilization for  a  dorsally  angulated  metaphyseal  fracture  is  neutral  to  slight flexion, 20  to  30 degrees  of  ulnar deviation  with  neutral  forearm rotation.    Radiographs  are  obtained  to  confirm reduction.  Although  palmarly  displaced,  extraarticular  Smith fractures  are  generally  unstable,  the  flexion–pronation  deformity  of  them  can  be  reduced  and  occasionally  stabilized  effectively  in  extension  and  supination  (45-60  degrees)  with  a  sugar tong  splint. 

The three-point bending principle   should  be  used  to  help  maintain  reduction; first dorsal molds  are  applied  over  the  metacarpals  and  the second over mid-diaphysis of  the  radius,  and  a  third  palmar  countermold  is  placed  over the  apex  of  the  fracture.  “Six-pack”  digital  exercises  are  begun immediately  to  reduce  edema  and  prevent  contractures  and disuse  atrophy. 

PERCUTANEOUS PIN FIXATION -

Percutaneous  pinning,  supplemented  by  an  external  fiberglass cast,  is  a  relatively  simple  and  effective  fixation  method  that  is applicable  for  reducible  extraarticular  fractures  and  simple articular  fractures  without  metaphyseal  comminution  but  with good  bone  quality.

Care  must  be  taken  to  avoid  injury  to  the  dorsal  sensory nerves,  particularly  when  transfixing  the  radial  styloid.

KAPANDJI TECHNIQUE 

 Kapandji  popularized  the  technique  of  “double  intrafocal wire  fixation”  to  both  reduce  and  maintain  distal  radial  fractures. This  technique  is  best  reserved  for  simple extraarticular  fractures  and  is  not  without  complications. 

EXTERNAL FIXATION-

1)Bridging or spanning fixation and 

2)Non-bridging or non-spanning fixation

AUGMENTED EXTERNAL FIXATION(Bridging)-

Indications

• Unstable extraarticular fractures of the distal radius (type I bending)

• Impacted articular fractures (type III compression)

• Comminuted unstable fractures with articular and metaphyseal involvement

Contraindications

• Severe osteoporosis

• Volar shear fractures (type II; Smith type II; volar Barton type)

• Patient preference, compliance concerns, or inability to care for the external fixation and pins

Technical points -

• Closure of pin cluster incisions before assembly of the fixator

• Gross alignment of the fragments by fixation in moderate traction, flexion, and ulnar deviation

• Assessment of the DRUJ for stability and augmentation as needed

PostoperativeCare

• Apply a sugar tong splint in supination for 5 to 10 days until suture removal.

• Start digital range-of-motion exercises immediately.

Non-bridging or non-spanning external fixation 

Indications -

 •fractures of the distal radius with actual or predicted instability, which are extra-articular or have an articular extension, which is undisplaced or reducible closed. There must be sufficient space in the distal fragment to site the pins. This usually requires 1 cm of intact volar cortex. 

Arthroscopic  Reduction  and  Percutaneous   Fixation  Technique-

•If considering  arthroscopically  assisted  reduction  and  fixation  of  an  articular  distal  radius  fracture,  it  is  good  to  reduce and  stabilize  the  fracture  in  a  splint  for  3  to  7  days  before planning surgery.  Treatment  of  fractures  acutely  by  arthroscopic  means may  limit  visibility due  to  bleeding  and  may  risk  the development  of  compartment  syndrome  because  of  extravasation  of  fluid  into  the  soft  tissues.  After  7  days,  however,  it becomes  difficult  to  elevate  impacted  articular  fragments without  a  formal  open  reduction.

Bone  Graft  and Substitutes -

• Supplemental  bone  graft  is  now  most  often  used  in  subacute  or nascent  malunions  requiring  osteoclasis ;  malunited  fractures; and,  less  frequently,  in  the  acute  situation  to  buttress  the  reduction  of  small  articular  fragments 

• The  use  of  a bone graft has  dramatically  decreased  during the  last  5  years to supplement internal  or external fixation. 

Open  Reduction  and  Internal  Fixation(ORIF)- 

Indication- 

• In active patients  where  satisfactory  reduction  cannot  be  maintained/achieved  by  closed  manipulation  and  casting,

• As an  alternative  to  percutaneous  fixation  because of preference  of   patient or  surgeon.

CONTRAINDICATIONS-

•Articular  fractures of  elderly,  inactive  patients,  and  in  those with  considerable  osteoporosis.

VOLAR OR DORSAL APPROACH -

The surgical  approach to be preferred depends  mainly  on  the  location  and  direction  of  displacement  of  the  fracture  fragments. Therefore, dorsally  or  radially  displaced  fractures  have  been  classically  approached  through  dorsal  incisions,  whereas  volarly  displaced  fractures  (e.g.,  the  Smith  and  reversed  Barton)  are classically  approached  through  palmar  exposures.

• Percutaneous  fixation  and bridge  plating,  should  be  considered alternative  to Open anatomic reconstruction in  cases  of  extreme  articular  comminution . In  these type of cases,  efforts  should be  focusing  at restoring  the  anatomic  relationships  of  the  radius  and  ulna  and to  ensuring  normal  alignment  of  the  hand  and  carpus  with  the long  axis  of  the  forearm  by  percutaneous  and  indirect  means. 

VOLAR PLATING-

Advantages  of  palmar exposure  and  volar  plating : 

•  Minimal volar  comminution  facilitates  reduction  of  dorsally displaced  fractures.

 •  Anatomic reduction of  the volar  cortex  facilitates  restoration of  radial  length,  inclination,  and  volar  tilt. 

• Preservation of  the vascular  supply  of  comminuted  dorsal  fragments  due to avoidance  of  additional  dorsal  dissection. 

 •  Since  the  wrist’s  volar  compartment is  having  larger  crosssectional  space  and  the  implant  is  separated  from  the  flexor tendons  by  the  pronator  quadratus,  the flexor tendon  complications  incidence   is  minimized. 

• Use  of  fixed angle  volar  plate  avoids  “toggling” of screw  in  the  distal  fragment  and  thus  reduces  the  danger  of secondary  displacement.

 • With help of a  fixed-angle,  internal-fixation  device that  uses  subchondral  pegs  or  screws, shortening and displacement(late)  of  articular  fragments can be  controlled  and  that  reduces the   need  for  bone  grafting.

Exposure-

•Through  the  distal  part  of  the  Henry approach in between  the  FCR  and  radial  artery  via  an  8-  to  9-cm longitudinal  incision. 

• "Hockey-stick”  extension  can  be  made  toward  the scaphoid  tubercle  if  additional  exposure  is  required.

• Detach the  pronator quadratus with an “L”-shaped incision and leave a portion of the split BR attached to the pronator for subsequent closure.

Technical Considerations-

•Avoid  placement  of  plate  distal  to  the  transverse  radial  ridge (i.e.,  the  so-called  “watershed”  line)  because  implants  on  the volar  lip  of  the  radius  are  in  direct  continuity  with  the  flexor tendons,  and  there  is  a  risk  of  tendon  irritation  and  rupture.  Hardware  placed  2  mm  or  more  above  the volar  critical  line  (Soong  Grade  1) or  within  3  mm  of  the distal  edge  of  the  volar  rim  (Soong  Grade  2)  has  been  demonstrated  to  have  a  high  rate  of  tendon  rupture.

 • For Irreducible Articular fractures(to  visualize  the dorsal  die-punch  and  centrally  impacted  fragments) , an extended FCR approach is an option:

a) Perform a tenotomy of the BR tendon.

b) Release the first dorsal compartment.

c) Pronate the proximal fragment to expose the articular surface.

FRAGMENT SPECIFIC FIXATION-

Robert  Medoff  devised  a  hybrid technique  of  percutaneous  wire  and  plate  fixation  designed to fix individual fracture fragments through several small  incisions. His “fragment-specific” classification defines articular fractures of the radius by recognition of five elemental fragments present alone or in combination in every fracture. Implants  are  placed  strategically along the radial and intermediate columns to maximize construct rigidity.

Mechanical studies using an unstable metaphyseal fracture model have proved  superiority of dual 2.0 mm plates placed at 50- 90 degrees to each other in axial plane  compared to  that of either K-wire–augmented external fixation or to a traditional 3.5-mm dorsal “T”-plate.Thus, the use of the term “fragment-specific fixation” does not refer to a particular implant type but to the concept of the use of two or more low-profile implants placed strategically along the columns of the distal radius to fix individual fracture fragments.

Examples-

1) Comminuted Dorsal Cortex 

2) Dorsal Intermediate Column Fragments 

3) Volar Ulnar Corner 

INTRA-MEDULLARY IMPLANTS - 

 Novel  intramedullary  (IM) methods  have now  been  developed  for  rapid  restoration  of radial  length,  alignment,  and  tilt;  they  are  designated  lowprofile,  minimal-incision  alternatives  to  other  previous methods. 

3)MANAGEMENT OF UNSTABLE EXTRA- ARTICULAR/MINIMAL ARTICULAR DISTAL RADIUS FRACTURE- 

DRUJ (Distal  Radioulnar  Joint)  INJURY Treatment  Options:

(1)  early  mobilization, 

 (2)  closed  treatment  and cast  immobilization  with  or  without  radioulnar  pinning,  and

(3)  operative  management,  including  open  and  arthroscopic techniques.

Assessment- 

assess  radioulnar  stability after  completion  of  radial fixation,  a  manual  “shuck”  test  of  the  ulna  is  performed  by grasping  the  ulnar  head  between  the  examiner’s  thumb  and index  finger  and  translating  it  dorsally  and  palmarly  within  the sigmoid  notch.  Gross  instability  is  manifested  by  frank  dislocation,  but  more  subtle  instability  can  be  appreciated  by  the  loss of  a  firm  endpoint  to  translation  and  by  increased  subluxation of  the  ulna  relative  to  the  uninjured  wrist.

COMPLICATIONS-

1) NERVE INJURY- 

•MEDIAN NERVE INJURY  is the most common nerve  associated with  distal radius fracture which presents as Carpal Tunnel Syndrome (CTS).

• presents in between 3% and 17% of fractures.

 Causes -

contributory causes of early CTS after distal radius fracture are swelling and hematoma extending into the carpal canal or deep to the fascia at the level of the fracture,  direct nerve contusion, hematoma block,and the Cotton-Loder position.

CTS can present at different intervals : 

1. Acute—within 1 week of fracture (27.4%).

 2. Subacute—1 to 12 weeks after fracture (44.3%). 

3. Delayed—more than 12 weeks after fracture (28.3%)

The acute onset group was younger and contained significantly more males, high-energy injuries, and AO type C injuries . While other two groups were having lower energy injuries and older womens .

• Decompression is successful in the majority of patients,but  sometimes compression may occur proximal to the wrist crease at the level of the fracture and release should be extended to this area.

ULNAR NERVE INJURY  is less common than median nerve injury 

• risk factors  are instability of the DRUJ  open fractures, high-energy injury, and severe fracture displacement. 

•Most of these injuries are neurapraxias which recover spontaneously. Exploration is recommended where there is complete ulnar palsy with an open wound or concurrent acute CTS.

2)TENDON INJURY- 

•Most commonly EPL Tendon(Extensor Pollicis Longus ) 

• Can be due to Hardware related or fracture related causes. 

•Hardware-related ruptures most commonly occur with volar or dorsal plating and are discussed  previously in the relevant sections.

• fracture-related ruptures occur earlier after injury at an average of around 6 weeks whilst later ruptures may be more likely to be related to attritional problems on hardware.

•Fracture-related flexor tendon injuries are much rarer possibly because the muscle belly of pronator quadratus acts as a cushioning layer between the flexor tendons and bone.

• If functional problem occurs after EPL rupture then tendon transfer, usually with extensor indicis proprius, should be considered.

3) MALUNION -

•Malunion of distal radius fracture is common , although it is not frequently reported. 

•Typical symptoms of malunion are as follows. 

1. Pain

—ulnar sided 

—carpal 

—radiocarpal 

2. Weakness of grip

3. Reduced range of movement, especially rotation 

4. Deformity 

•Pain is a common symptom of distal radius malunion and can be located in the DRUJ, the carpal area or the radiocarpal joint .

•Treatment of Symptomatic Malunion In the fit independent patient  is surgical(distal radial osteotomy ).

 4) NONUNION- 

•Nonunion of the distal radius is rare occurring in well under 1% of fractures and may occur in the presence of extensive metaphyseal comminution. The diagnosis is made in the presence of continuing pain and increasing deformity. It is usually treated with plating and bone grafting to which most nonunions are amenable even with small distal fragments.Wrist fusion should be reserved for cases where plating and bone grafting fail.

5)Complex Regional Pain Syndrome (CRPS)-

CRPS is a serious and often debilitating complication of a number of injuries but is most commonly seen after distal radius fracture. Its etiology is unknown and it is characterized by a number of symptoms and signs including pain, swelling, color and temperature change, and joint contracture.