Hamate Fractures – Causes, Symptoms, Treatment

Hamate fractures are rare and underreported. These injuries are usually misdiagnosed or confused with simple wrist sprains. Delayed diagnosis is not uncommon. The hamate is a triangular-shaped bone that forms part of the distal carpal row, articulating with the capitate (radially), triquetrum (proximally), and fifth and fourth metacarpals (distally).

Considering its unique anatomy (Figure 1), hamate fractures usually get subdivided into two broad groups: hook fractures and body fractures.

Classification of hamate fractures:

  • Type 1: Hook of the hamate fracture

  • Type 2: Body of the hamate fracture

    • 2a: Coronal (may be dorsal oblique or splitting fracture)
    • 2b: Transverse fracture

Associated hook fracture injuries:

  • Ulnar artery injury
  • Ulnar nerve injury

Associated body fracture Injuries:

  • Fourth and fifth metacarpal fracture-dislocation
  • Greater arc perilunate fracture-dislocation

Diagnosis

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.

Differential Diagnosis

Ulnar flexor carpi tendinitis and triangular fibrocartilage complex injuries are a common misdiagnosis. A hamate fracture accompanies a small percentage (1 to 2%) of distal radius fracture.

Other differential diagnoses include:

  • Bipartite hamate
  • Scaphoid fracture
  • Capitate fracture
  • Triquetrum fracture
  • Pisiform fracture
  • Ligamentous injuries (without fracture)
  • Carpal bone dislocations

Treatment / Management

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.

Surgery

Surgical indications: displaced fractures, nonunion, ulnar nerve compression, median nerve compression, ulnar artery compression, tendon rupture and metacarpal subluxation.

  • Hook fractures:

    • Acute, nondisplaced: Immobilization, ulnar gutter cast for six weeks. There is still debate whether patients may profit from initial surgical treatment in this type of fracture. Sports players will usually benefit from early surgical management, returning to sports activities in three months.
    • Acute, displaced: Excision of a bony fragment is the gold standard procedure. Open reduction and internal fixation (screws or Kirschner wires) is another proven treatment. Both alternatives showed similar clinical results.
    • Chronic pain, nonunion: These signs require fracture pinning with bone grafting.

  •  Body fractures:

    • Acute, nondisplaced: Immobilization, six-week cast.
    • Acute, displaced: Open reduction and internal fixation (Kirschner wires, grid plate, or headless compression screws).

Surgical tech tips:

  • The motor branch of the ulnar nerve must be clearly spotted and retracted before hook excision or drilling.
  • After fractured fragment excision, periosteum closure should be over the base of the remaining body to protect the ulnar nerve and tendons

Complications

  • Nonunion
  • Posttraumatic arthritis
  • Avascular necrosis in proximal pole (body fractures)
  • Ulnar nerve compression (Guyon´s canal)
  • Carpal tunnel syndrome
  • Flexor digitorum profundus tendon rupture
  • Ulnar artery thrombosis (hypothenar hammer syndrome)
  • Ulnar artery compression
  • Residual instability of fourth and/or fifth metacarpals
Nonunion – This is the most likely complication arising from missed scaphoid fractures. The risk is higher in those that are very displaced or have associated carpal fractures. These will generally require operative intervention with screw fixation. There are three stages:
  • 1 – Radioscaphoid arthritis
  • 2 – Scaphocapitate arthritis
  • 3 – Lunocapitate arthritis

Scaphoid nonunion advanced collapse (SNAC) is the end-stage and is managed with wrist fusion or proximal row corpectomy.

  • Avascular necrosis – The incidence of this is approximately 30-40%. This is most likely to affect the proximal pole
  • Scapholunate dissociation
  • Delayed union – typically 90-95% if operatively managed fracture unites, but if there is doubt, CT scan may be needed to confirm union.