Monteggia Fractures – Causes, Symptoms, Treatment

Monteggia fractures

Monteggia fractures most commonly result from a direct blow to the forearm with the elbow extended and forearm in hyperpronation. The energy from the ulnar fracture gets transmitted along the interosseous membrane leading to rupture of the proximal quadrate and annular ligaments, disrupting the radiocapitellar joint. In conjunction with the bimodal distribution, diaphyseal forearm fractures in young males are commonly due to high-energy trauma, for example, falls from height, sports injuries, motor vehicle accidents, and fractures in elderly females are due to low-energy trauma such as a ground-level fall.

Classification System of Monteggia Fractures

In 1967, Dr. Jose Luis Babo classified Monteggia fractures into four types. These types depend on the direction of the radial head dislocation.

Type I

  • The proximal ulna is fractured and radial head dislocation is directed anteriorly.
  • Most common type in children accounts for 70% of cases, 15% of cases in adults.
  • Mechanism of Injury: (1) direct blow to the posterior elbow, (2) hyper-pronated force on an outstretched arm, (3) contracted biceps resists forearm extension causing dislocation and followed by impact leading to ulna fracture.

Type II

  • Both the ulnar shaft fracture and radial head dislocation are directed posteriorly
  • Mechanism of Injury: Axial load directed up the forearm with a slightly flexed elbow.
  • Most common type in adults accounting for approximately 80% of cases.
  • Associated with an instability of the ulnohumeral joint and high rates of radial head fracture and posterior interosseous nerve injury.

Type III

  • Ulnar fracture with a radial head dislocation directed laterally.
  • Mechanism of Injury: Varus force on an extended elbow leads to a greenstick fracture of the ulna.
  • More frequently seen in children.

Type IV

  • Fractures of the ulnar and radial shafts with an anterior radial head dislocation
  • Rarest type and poorly understood mechanism.

Causes of Monteggia Fractures

Mechanisms include:

  • Fall on an outstretched hand with the forearm in excessive pronation (hyper-pronation injury). The ulna fractures in the proximal one-third of the shaft due to extreme dislocation. Depending on the impact and forces applied in each direction, degree of energy absorption determines pattern, the involvement of the radial head, and whether or not open soft tissue occurs.
  • Direct blow on the back of the upper forearm would be a very uncommon cause. In this context, isolated ulnar shaft fractures are most commonly seen in defense against blunt trauma (e.g. nightstick injury). Such an isolated ulnar shaft fracture is not a Monteggia fracture. It is called a ‘nightstick fracture’.

Diagnosis of Monteggia Fractures

History

Your doctor in the emergency department may ask the following questions

  • How – How was the fracture created, and, if chronic, why is it still open? (underlying etiology)
  • When – How long has this fracture been present? (e.g., chronic less than 1 month or acute, more than 6 months)
  • What – What anatomy and structure do it involve? (e.g., epidermis, dermis, subcutaneous tissue, fascia, muscle, tendon, bone, arteries, nerves). What comorbidities, economic or social factors do the patient have which might affect their ability to heal the fracture?
  • Where – Where on the body parts is it located? Is it in an area that is difficult to offload, complicated, or keep clean? Is it in an area of high skin tension? Is it near any vital organ and structures such as a major artery?
  • What is your Past – Has your previous medical history of fracture? Are you suffering from any chronic disease, such as hypertension, blood pressure, diabetes mellitus, previous major surgery? What kind of medicine did you take? What is your food habits, geographic location, Alcohol, tea, coffee consumption habit,  anabolic steroid uses for athletes, etc?

Physical

Physical examination is done by your doctor, consisting of palpation of the fracture site, eliciting boney tenderness, edema, swelling. If the fracture is in the dept of a joint, the joint motion, normal movement will aggravate the pain.

  • Inspection – Your doctor also check superficial tissue, skin color, involving or not only the epidermal layer or Partial-thickness affects the epidermis and extend into the dermis, but full-thickness also extends through the dermis and into the adipose tissues or full-thickness extends through the dermis, and adipose exposes muscle, bone, evaluate and measure the depth, length, and width of the fracture. Access surrounding skin tissue, fracture margins for tunneling, rolled, undermining fibrotic changes, and if unattached and evaluate for signs and symptoms of infect warm, pain, delayed healing.
  • Palpation – Physical examination may reveal tenderness to palpation, swelling, edema, tenderness, worm, temperature, open fracture, closed fracture, microtrauma, and ecchymosis at the site of fracture. Condition of the surrounding skin and soft tissue, quality of vascular perfusion and pulses, and the integrity of nerve function.
  • Motor function – Your doctor may ask the patient to move the injured area to assist in assessing muscle, ligament, and tendon function. The ability to move the joint means only that the muscles and tendons work properly, and does not guarantee bone integrity or stability. The concept that “it can’t be fractured because you can move it” is not correct. The jerk test and manual test are also performed to investigate the motor function.
  • Sensory examination – assesses sensations such as light touch, worm, paresthesia, itching, numbness, and pinprick sensations, in its fracture side. Sensory 2-point discrimination
  • Range of motion – A range of motion examination of the fracture associate joint and it’s surrounding joint may be helpful in assessing the muscle, tendon, ligament, cartilage stability. Active assisted, actively resisted exercises are performed around the injured area joint.
  • Blood pressure and pulse check – Blood pressure is the term used to describe the strength of blood with which your blood pushes on the sides of your arteries as it’s pumped around your body. An examination of the circulatory system, feeling for pulses, blood pressure, and assessing how quickly blood returns to the tip of a toe to heart and it is pressed the toe turns white (capillary refill).

Lab Test

Laboratory tests should be done as an adjunct in overall medical status for surgical treatment.

Associated nerve injury

– paralysis of deep branch of the radial nerve is most common;
– the posterior interosseous nerve may be wrapped around the neck of radius, preventing reduction;
– note: that patients whose operative treatment is delayed may be found to have a progressive PIN palsy from
constant pressure exerted by the dislocated radial head;
– spontaneous recovery is usual & exploration is not indicated;

– Radiographs:
– dislocation of radial head may be missed, even though frx of the ulna is obvious (need AP, lateral and oblique X-rays of the elbow)
– a line is drawn thru radial shaft and radial head should align w/ capitalism in any position if the radial head is in normal position
– this is esp true on the lateral projection;
– the apex of angular deformity of ulna usually indicates the direction of radial head dislocation;

– Reduction:
– immobilize forearm in neutral rotation w/ slight supination, w/ cast carefully molded over the lateral side of the ulna at the level of fracture;
– keep elbow flexed ( > 90 deg), to relax biceps so that full supination can be avoided w/o losing reduction;

– Non-Operative Treatment:
– realize that even w/ successful closed reduction of the ulna (and accompanying reduction of the radial head) that subsequently
there may be slow and progressive shortening and angulation;
– hence, these patients will require close follow up;

Treatment of Monteggia Fractures

  • Nonoperative
    • closed reduction 
      • indications
        • more common and successful in children
        • must ensure stabilty and anatomic alignment of ulna fracture
      • technique
        • cast in supination for Bado I and III
  • Operative
    • ORIF of ulna shaft fracture
      • indications
        • acute fractures which are open or unstable (long oblique)
        • comminuted fractures
        • most Monteggia fractures in adults are treated surgically
    • ORIF of ulna shaft fracture, open reduction of radial head
      • indications
        • failure to reduce radial head with ORIF of ulnar shaft only
          • ensure ulnar reduction is correct
        • complex injury pattern
    • IM Nailing of ulna
      • indications
        • transverse or short oblique fracture

Do no HARM for 72 hours after injury

  • Heat – Heat applied to fracture and injured side by hot baths, electric heat, saunas, heat packs, etc has the opposite effect on the blood flow. Heat may cause more fluid accumulation in the fracture joints by encouraging blood flow. Heat should be avoided when inflammation is developing in the acute stage. However, after about 72 hours, no further inflammation is likely to develop and heat can be soothing.
  • Alcohol –  stimulates the central nervous system that can increase bleeding and swelling and decrease healing.
  • Running and movement – Running and walking may cause further damage, and causes healing delay.
  • Massage – A massage also may increase bleeding and swelling. However, after 72 hours of your fracture, you can take a simple message, and applying heat may be soothing the pain.

Medication

The following medications may be considered by your doctor to relieve acute and immediate pain, long term treatment

What To Eat and What  to avoid

Eat Nutritiously During Your Recovery

All bones and tissues in the body need certain micronutrients in order to heal properly and in a timely manner. Eating a nutritious and balanced diet that includes lots of minerals and vitamins is proven to help heal broken bones and all types of fractures. Therefore, focus on eating lots of fresh food produce (fruits and veggies), whole grains, cereal, beans, lean meats, seafood, and fish to give your body the building blocks needed to properly repair your fracture. In addition, drink plenty of purified mineral water, milk, and other dairy-based beverages to augment what you eat.

  • Broken bones or fractures bones need ample minerals (calcium, phosphorus, magnesium, boron, selenium, omega-3) and protein to become strong and healthy again.
  • Excellent sources of minerals/protein include dairy products, tofu, beans, broccoli, nuts and seeds, sardines, sea fish, and salmon.
  • Important vitamins that are needed for bone healing include vitamin C (needed to make collagen that your body essential element), vitamin D (crucial for mineral absorption, or machine for mineral absorber from your food), and vitamin K (binds calcium to bones and triggers more quickly collagen formation).
  • Conversely, don’t consume food or drink that is known to impair bone/tissue healing, such as alcoholic beverages, sodas, fried fast food, most fast food items, and foods made with lots of refined sugars and preservatives.

Delayed Dx:
– when dx is delayed < 3 months, ORIF is indicated;
– when > 3 months has elapsed, consider non-op treatment because bony ankylosis of the elbow may occur following surgery;
– bony ankylosis may be more disabling than the joint instability
– in a child, a dislocated radial head should never be resected, since it will cause cubitus valgus, prominence of the distal end of ulna,
and radial deviation of the head

Pearls and Pitfalls of Technique

  • Missing pediatric – Monteggia leads to poor results. All “isolated ulna fractures” must be scrutinized for radio capitellar subluxation. Careful weekly radiographic follow-up, for the first 3 weeks after reduction is important to ensure the maintenance of reduction throughout treatment.
  • Radiographic reading – Radiocapitellar line: The radial neck line should bisect the capitellar ossific nucleus.
  • Ulnar bow sign: subtle bowing in the direction of the radial head dislocation. The posterior ulnar border should be straight.
  • Most pediatric Monteggia fractures can be treated via closed means. Comminution, long oblique, and very proximal ulna fractures have a higher risk of needing operative fixation.
  • Residual radiocapitellar instability is almost always a result of residual ulnar deformity.
  • Adult fractures often involve collateral ligament injury and radial head and coronoid fractures.
  • The surgeon should be prepared to perform appropriate repairs and replacements.
  • Osteoporosis must be taken into account when treating adult fractures. The threshold should be low for use of locking plate technology and for replacement instead of repair of the radial head.

References