UMEM Educational Pearls - Orthopedics

Elbow Dislocation

• The elbow is the second most commonly dislocated joint after the shoulder in adults. 
• It is the most commonly dislocated joint in children.
• 90% of all elbow dislocation are posterior.  A considerable amount of force is required to dislocate the elbow so be highly suspicous for associated fractures of the radial head, or coronoid process of the ulna. 
• The combination of a radial head fracture, coronoid process fracture and elbow dislocation is known as the terrible elbow.
• Anterior elbow dislocations can be associated with injuries to the brachial artery, median and ulnar nerves. 

Quick clinical clues that the elbow is dislocated:

• Posterior dislocation typically will have a prominent olecranon process, the arm is flexed at the elbow, and the forearm will appear shortened.
• Anterior dislocation typically present with the arm in extension and the forearm will appear elongated.

Trimallelor Fractures:

Bimallelor fracture involve both the medial mallelous of the tibia and the distal fibula.  The third malleloi is the posterior tip of the articular surface of the tibia. Can result in instability in the posterior and lateral directions along with external rotation.

Some indications for Open Reduction Internal Fixation when the posterior mallelous is fractured are:

• > 25% of the posterior articular surface being involved.
• Fractures that allow posterior subluxation of the talus
• Fractures that are displaced more than 2 mm
• Fractures that can not be reduced satisfactorily.

Knee Dislocations:

Are relatively rare injuries, but can result in loss of the limb if missed.  Patients will sometimes say they dislocated their knee when they actually mean their patella, so a good history where they describe what their knee looked like, and what they were doing at the time will help differentiated the two.

Some signs that you are dealing with a spontanously reduced knee dislocation are:

• Varus or valgus instability in full extension of the knee is suggestive of a grossly unstable knee
• Pain out of proportion to injury
• Absent or decreased pulse

The loss of limb is due to unrecognized injury to the popiteal artery which as be estimated to occur 7-45% of the time. 

• Normal pulses and a normal capillary refill does NOT rule out as significant vascular injury. 
• Arteriograms are no longer mandatory in all cases, but it is generally recommended that you perform an ankle-brachial index and get a vascular duplex scan of the popiteal artery to exclude dissections, tears, aneurysms and psuedo-anuerysms that can all occur as a result of the dislocation.

If you would like to see some videos of knee injuries in the making follow this link www.csmfoundation.org/Educational_Lower_Extremity.html

Distal Radius Fractures

• The radius is the most commonly fracutred bone of the arm.
   
• The Colles fracture is a fracture of the distal radius that is angulated dorsally [The distal fragment is angulated towards the back of the hand.]
   
• The Smith fracture is similar but the distal fracture is angulated volarly [towards the palm of the hand]
   
• Other less commonly named fractures are the:
  • Barton's - an intraarticular fracture fo the distal radius with dislocation of the radiocarpal joint.  Typically occrus as a fall on the extended and pronated wrist.
     
  • Chauffeur's fracutre - a fracture of the radial styloid process.  Typically caused by compression of the scaphoid against the styloid.  Also known as a hutchinson fracture.

• Fractures of the phalanx are common, and fractures of the proximal phalanx can lead to significant disability if not treated appropriately.

• Be sure to check for malrotation, which is a common problem.  Check for this by examing for the normal cascade in finger flexion with the tips of the fingers pointing toward the proximal portion of the scaphoid

• Acceptable Reduction:
  • No rotational deformity can be accepted
  • No more than 10 deg of angulation should be accepted in any plane
  • Malreduction will cause loss of equilibrium between flexor and extensor tendons.

• Place the splint on the dorsum side of the finger so that the patient can still have sensation of the tip of their finger tip.

• Patients requiring prompt referral to a hand surgeon are those with:
  • Intraarticular fractures
  • Malrotation
  • Unacceptable reductions
  • Unstable fractures

Radial Head Fractures:

Radial head fractures are more common in adults, where radial neck fractures are more common in children.  Remember to look for fat pads to help make the diagnosis if it is not obvious on plain films.  On plain films, a line drawn down the middle of the radial head should always line up with the capitellum of the humerus.  If this does not occur the radial head is dislocated and/or fracture.

Orthopaedics use the Mason classification to help guide treatment, and break down fractures into 3 different types.

• Type I - is undisplaced, generally treated nonoperatively. 
  • Early mobilization prevents chronic elbow stiffness.
• Type II - a single fragment is displaced.
  • May be treated nonoperatively if the displacement is minimal.
  • The rule of threes is used. Nonsurgical treatment can be considered if the fracture involves less than one third of the articular surface, less than 30° of angulation, and if displacement is less than 3 mm
• Type III  - is comminuted.
  • Usually require operative intervention.

Hamate Fractures:

• Typically the result of a direct blow, and the hook of the hamate is commonly fractured in batters or golfers.
• Like the scaphoid, the hook is at risk for avascular necrosis and non-union of the hook.
• Fractures of the body are more common than fracture of the hook of the hamate
• On exam you will typically find:
  • Increased pain with axial loading of ring (4th) and little finger (5th) metacarpals
  • Most patients complain of pain and tenderness on ulnar side of palm or on the dorsoulnar aspect of the wrist.
  • Pain also aggravated by grasping items.
• Diagnosis
  • Fracture often missed on routine AP & lateral films
  • Most fractures can be diagnosed by plain films if you as for the "Carpal tunnel view"
  • CT scan can also be used to see the fracture
• Treatment
  • Good Immobilization will often prevent avascular necrosis and allow early healing
    • Volar splint or short arm cast are usually adequate.
  • Excision of the hook of the hamate provides similar results as an ORIF in those that have non-union or displaced fractures.
  • Refer to orthopedics

Show References

Lunate Dislocation and perilunate dislocation are broken down into 4 stages that relates to the progressive disruption of the carpal ligaments due to hyperextension and ulnar deviation of the wrist:

• Stage 1: Scapholunate Dislocation
  • Has the characteristic sign of widening of the scapholunate joint on the PA view known as the Terry Thomas Sign as it resembles the gap between his teeth
  • Gap between scaphoid and lunate should be less than 2 mm
• Stage II: Perilunate dislocation
  • Best seen on lateral view of the wrist
  • Associated with scaphoid fractures
  • Lunate stays in its normal position with the capitate dislocation posterior when you use the distal radius as your reference point
• Stage III: Perilunate dislocation
  • Also includes dislocation or fracture of the triguetrum
  • Triquetrial and scaphoid malrotation
  • In lateral view, all other carpal bones are dislocated posterior with respect to lunate
• Stage IV:  Lunate dislocation
  • On PA view you will see a triangular view of the lunate on the PA view that looks like a "piece of pie". 
  • On the lateral view of the wrist the lunate will look like a tea cup tipped in the volar direction AKA the "spilled teacup sign"
  • Associated with a scaphoid fracture
     

For a good indepth review of lunate and perilunate injuries please read the article by Andy Perron with this attached link.... doi:10.1053/ajem.2001.21306   

If you are interested in seeing some xray examples please visit LearningRadiology.com

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A lot of what is taught about fracture patterns in abused children has been extrapolated from post-mortem studies which is a different population then what you will see in the Emergency Department. The study referenced did a metanalysis of all the literature in an attempt to determine what fractures suggest abuse and looked at all comers that had fractures.  Some of the patterns they were able to extrapolate are:

• Fractures from abuse predominately occurred in infants and toddlers
  • In children less than 12 one study showed that 80% of all fractures from abuse occurred in children less than 18 months old.
  • In children over 5 years old 85% of fractures are not caused by abuse
• In children under 3 years old, skull fractures were by far the most common fracture type in both abused and non-abused children.
  • However, the presense of a skull fracture only has a 1:3 chance of being from abuse.
  • Skull fractures location and type are similar between abuse and non-abuse, though multiple fractures and fractures that cross suture lines are more highly associated with abuse.
• There is a strong relationship between multiple fractures and abuse
  • 74% of abused children had two or more fractures compared to 16% of non-abused
• In the absence of a confirmed traumatic case, rib fractures have the highest probability (71%) of being caused by abuse.
• Humeral fractures have a 1:2 chance of being the result of abuse.
• Femur fracture like skull fractures have a 1:3 chance of being the result of abuse.

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The Galeazzi Fracture:

• It is a fracture of the distal to middle third of the radial shaft with dislocation of the Distal Radio-Ulnar Joint. 
• Typical mechanism of injury is a fall onto a outstretched hyperpronated forearm.
• Estimated to represent 7% of adult forearm fractures.
• This fracture requires surgical repair (Open reduction and internal fixation) in order to prevent presistant or recurrent dislocation of the distal ulnar which typically occurs with closed reduction techniques.
• Associated with injury to the Anterior interosseous nerve which is a purely motor branch of the median nerve.  Injury results in paralys of the flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) to the index finger, resulting in loss of the pinch mechanism between the thumb and index finger.

To see a photo of a Galeazzi fracture please visit the Learning Radiology Website by clicking on the following link:

http://www.learningradiology.com/caseofweek/caseoftheweekpix2/cow157lg.jpg

Most people are familiar with the Ottawa Ankle Rules, but there are also Ottawa Knee and Foot rules.  The Ottawa rules help to limit the number of x-rays you may need in patients that present with ankle, foot or knee pain after an injury.

The Ottawa Ankle Rule

An ankle x-ray is only needed if there pain in the mallelolar area and any of the following:

• Bone tenderness at the posterior tip of the base of the lateral mallelous
• Bone tenderness at the posterior tip of the base of the medial mallelous
• Inability to weight bear immediately and in the Emergency Department

The Ottawa Foot Rule

A foot x-ray is only needed if there is pain in the midfoot and any of the following:

• Bone tenderness at the base of the 5th metatarsal
• Bone tenderness over the navicular
• Inability to weight bear immediately and in the Emergency Department

The Ottawa Knee Rule

A knee x-ray is only needed for knee injury patients when they have any of the following:

• Age 55 or over
• Isolated tenderness of the patella (no bone tenderness of the knee other than the patella)
• Tenderness at the head of the fibula
• Inability to flex to 90 degrees
• Inability to weight bear both immediately and in the Emergency Department (4 steps - unable to transfer weight twice onto each lower limb regardless of limping).

Ankle sprains are typically treated with a short period of immbolization and then functional exercises are prescribed to rehabilitate the ankle.  A study published in the Lancet this week might just change that.  Lamb et al looked at 584 people with severe ankle sprains (unable to weight bear 3 days out from injury) that were randomized to be treated with a 10 day below knee cast, Aircast, Bledshoe Shoe or Tubular Compression dressing (similar to Ace Wrap).  Those that were treated with the Cast and Aircast had quicker return to function and less disability at 3 months.  There was no increased risk of DVTs in the cast group.

A commentary in the same issue points out that severe ankle sprains are associated with:

• lower levels of physical activity levels
• recurrent ankle sprains are often reported for months and years after initial injury.
• About 30% of patients with an initial ankle sprain develop chronic ankle instability, or repetitive giving way of the ankle during functional activities.
• There is also emergent evidence to link severe and repetitive ankle sprains to increased risk of ankle osteoarthritis.

Based on this article I think it is prudent to treat all patients with severe Ankle Sprains with a prolonged period of forced immobilzation (Posterior Splint, Short Leg Cast or Aircast).  I would also recommend the Aircast be used to prevent recurrent sprains especially if the patient is involved in sports that require jumping (Basketball, Volleyball) where the risk of reinjury is higher.

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A maisonneuve fracture is a fracture dislocation resulting from external rotational forces to ankle -- through interosseous ligament to fibula.

• Proximal fibula fracture - from external rotational forces (spiral/oblique)
• Ankle components can include any of the following:
  • medial maleolus avulsion fx or deltoid ligament rupture
  • anterior talofibular ligament rupture
  • interosseous ligament rupture
  • posterior malleolar fracture

If stability is questionable, orthopedic evaluation under anesthesia is required. Additionally always consider compartment syndrome. Do not rely on Kanduval's signs (pain, paraesthesia, pallor, poikilothermia, pulselessness) - "... with the exception of pain and paraesthesia, these traditional signs are not reliable." Emergent orthopedic consultation and compartment pressure assessment should be performed. (see attached photos)

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Management of Felons

• An abscess of distal finger that involves the pulp. 
• A difficult infection to treat due to fibrous septa that divide the pulp into multiple small compartments. 
• These septa run from the periosteum to the skin increasing the risk of osteomyelitis
• Patients typically present with a lot of pain, redness, and swelling.
• Typically triggered by a puncture wound (i.e.: splinter)
• Incision and Drainage can result in a:
  
  • anesthetic finger tip
  • unstable finger pad
  • neuroma
• If you are going to drain one it is recommended that you do a volar longitudinal incision down the middle of the finger pad or a high lateral incision. 
• The high lateral incision should be at about 5 mm below the nail plate border. This distance should allow for avoiding the more volar neurovascular structures.

For good photos of the incision technique please visit the reference article listed.

Clark, DC. Common Acute Hand Infections. Am Fam Physician 2003;68:2167-76

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Mallet Finger:

A common injury resulting in a tear or avulsion of the extensor digitorium tendon inserting into  the base of the distal phalanx.  Occurs due to hyperflexion of the finger usually as of a esult of it getting jammed on a ball while playing sports.  Most can be treated non-surgically.

The distal phalanx must be kept in full extension for 6 to 8 weeks. This is one of the few times that the finger should not be splinted in the position of function.

Make sure that patient is informed that if they remove the splint and flex their finger the 6 to 8 week healing window will be reset to day 0.  These patients should not be doing ROM exercises and must wear the splint full time.

Splinting Pearls:

1. When using plaster of paris remember to use at least 10 layers for upper extremities and 15-20 layers for lower extremities.
2. Always apply the splint so that the joint above and below the fracture is immobilized.
3. On radius and ulnar fractures, a sugar tong splint will provide better immobilzation as it also prevents supination/pronation where a posterior long arm or volar splint only prevent flexion and extension.
4. Remember to make sure that the hand is placed in the position of function.
5. Though not required a stockinette provides an additional layer of skin protection and helps to make the ends of the splint looking cleaner.  It can also help hold the splint in place as you ace wrap it.
6. Finally, make sure that you document neurovascular status pre and post splint placement and if any manipulation is done you should have a follow up xray taken to ensure alignment is satisfactory.

Olecranon Bursitis is inflammation and swelling of the bursa overlying the olecranon process of the ulna.  Can result from trauma, overuse, or infection. 

Treatment can consist of:

• Aspiration:  Can be done to rule out infection [send gram stain, culture, and cell count], and be therapeutic by removing the excess fluid.
• NSAIDs
• Local injection of corticosteroids into the bursa
• Wearing of a neopryne elbow sleeve, or ace wraps to provide compression over the bursa and may help prevent reaccumulation of the fluid.

Remember aspiration has some major risks that need to be explained to the paitent:

• Infection may be introduced during the aspiration.  [Follow aseptic techniques and ensure that the skin is adequately prepped with chlorhexidine or betadiene].
• Formation of fistula tract with chronic drainage. [Use a Z or zigzap approach to minimize this complication.]
• Ulnar nerve injury.  Avoided by using a posterior lateral approach and avoiding a medial approach.

They also need to know that the fluid will likely reaccumulate.  So aspiration is not a guaranteed cure. 

When examining a knee for a meniscal injury the commonly described tests are the McMurray Test and Apley Test.  However, these tests have sensitivities of 48-68% and 41% respectfully, and specificities of 86-94% and 86-93% respectfully.  Depending on whether you are looking at the medical or lateral meniscus.

The Tessaly Test that was first described in 2005 can be performed with knee in either 5 or 20 degrees of flexion and has a senstivity of 89-92% and specificity of 96-97% when performed in 20 degrees flexion.  The test also tends to be easier to perform.

To perform the test:

1. Stand on affected leg only with the other leg held up in the air.  The examiner holds hands for balance.
2. Flex knee to be test to 20 degrees, while the other leg is held in the air
3. Internally and Externally Rotate Knee
4. Positive test is pain at medial or lateral joint line with possible locking/catching sensation

Essentially you and your patient will look like you are doing the twist as they rotate their knee with you holding their hands.

Show References

Fracture Management:

In order to maximize billing when caring for patients with fractures two things should be done:

1. The physician does not need to place the splint, but the physican must document that they checked the splint for proper placement and alignment for it to be billed appropriately..
2. Emergency physicians also provide a lot of "definitive" care for fractures.  (i.e.: we provide the same care that the treating specialist would provide) and can bill for a higher level if this is documented properly. 
   1. For instance, if you are treating a impacted, stable distal radius fracture with a splint and pain medication this is the same definitive care the orthopedist would do as they are only going to exchange your splint for  a cast. 
   2. Another example is the treatment of rib fractures which may consist only of pain control, incentive spirometry and instructions to prevent pneumonia.
   3. In these patients, have the patients follow up more than 48 hours later.  If you document that the patient will followup in less than 48 hours, most auditors and billing companies will assume you are not providing definitive care and will not code for the higher earning RVU.

Finally,  you should obtain post-reduction x-rays on any fracture that you manipulate and document that the patient is neurovascularly intact prior to discharge.

SCAPHOID FRACTURE:

• One of the most frequently missed fractures in the ED
• Most common carpal fracture.
• 10-20% fractures are “occult”
• Significant long-term complications:
  
  • Non-union
  • Avascular necrosis
• Complications more common due to the fact the blood supply comes form from the distal end of the bone.
• The more distal the fracture, the greater risk of complications
• MR remains the best test for occult fx.