Tendon Injury

Tendons are long fibrous bands that extend from the bones of the hand and fingers to the muscles in the forearm which then contract and provide for movement.

  • There are two types of tendons: extensors and flexors
    •  Extensor tendons: run along the back of the hand and allow you to straighten your wrist and fingers
    • Flexor tendons: run along the palm of the hand and are responsible for your ability to bend your wrist and fingers, allowing you to grasp objects and form a fist.
  • Tendon Injury
    • A tendon injury is usually caused by a penetrating injury to the hand or fingers, typically due to laceration or puncture wound, but have also been seen in blunt impact or crush injuries where no sharp cuts are identified.
    • Tendon injuries may also be seen in conjunction with other traumatic injuries such as fractures, dislocations, and crush injuries. Crush injuries specifically are frequently associated with damage to multiple structures, including the surrounding soft tissue, nerves, arteries and bones.
    • Extensor Tendon Injuries:
      • These tendons are found on the back, or dorsal, side of the hand and fingers.
      • Injury to extensor tendons limit the ability to fully straighten fingers, and your finger will appear to droop down at the joint near the injury.
      • Surgery is required to repair the tendon and restore function
    • Flexor Tendon Injuries:
      • Tendons found on the palm, or volar, aspect of the hand and fingers
      • Injury to flexor tendons limit the ability to bend fingers, and they will appear straight at the joint near the injury.
      • Surgery is required to repair the tendon and restore function
  • Diagnosis
    •  Tendon injuries are diagnosed by evaluating strength and range of motion at different parts of the fingers where different tendons are attached.
      •  Weakness and problems with straightening or bending the fingers can be signs of a tendon injury!
    • The extent of a tendon injury is not always obvious from physical exam alone. It is possible to have a “normal” exam, meaning the fingers move correctly and have an appropriate level of strength against resistance, and still have an injury which requires repair.
      • Tendons are made up of many strong fibers, and will generally work appropriately when even 95% of the tendon is damaged. However, any tendon with 50% or greater of an injury is at a very high risk of rupture, meaning the remaining tendon fibers will tear apart while using it for normal daily activities at work or at home. If this happens, the injured finger will stop working, and the torn tendon edges will be frayed, which requires cutting off the damaged edges to ensure a smooth, functional repair. However, this type of repair is quite tight due to the necessity of removing the damaged ends, and is associated with a higher risk of complication including re-rupture, stiffness, and functional problems with range of motion. For this reason, any laceration which occurs over the area of a tendon is typically recommended a trip to the operating room for exploration of the injury, and repair of any identified damaged tendons and surrounding structures.
      • Frequently an injury that appears very small and simple on the surface can cause severe and complex damage to deeper structures.
  • Repair & Recovery
    • Depending on the exact location and extent of the injury, surgery may be performed at the hospital under anesthesia or in the office using only local numbing medicine. This will be determined at your inital consult based on the history of your injury and your specific exam. If a partial injury is suspected, this may be able to be performed under local numbing medicine.
    • You can expect to have a bigger cut, as identifying the complete injury and then repairing it typically involves an extension incision of the initial laceration.
    • After surgery, you can expect sutures along the incision site, a splint involving the entire hand and forearm, and follow up within one week at clinic.
    • Early motion protocol is followed with patients referred to Hand Occupational Therapy with a Certified Hand Therapist as soon as possible after surgery. These therapists are very knowledgeable in normal healing timelines for a variety of hand injuries and will guide you in safe movement as your injury heals. Hand therapy is an important part of your recovery as this will help to prevent stiffness and scarring which can impact long term function.
    • Several post-op clinic visits as well as Hand Occupational Therapy will establish gliding, decrease unwanted adhesions, and enhance the healing process and return to normal function.
  • If you are concerned about or suspect a tendon injury to your hand, please call Dr. Mehan’s office to arrange for a thorough evaluation.

Nerve Injury

Nerves are the wiring system that carry messages from the brain to the rest of the body. An outer layer of tissue, called the sheath or epineurium, forms a cover to protect the nerve itself, which contains millions of individual fibers grouped in bundles within the sheath.

  • Types of nerves
    • Motor nerves carry messages from the brain to muscles to make the body move.
    • Sensory nerves carry messages from the brain to different parts of the body to signal pain, pressure, temperature, proprioception.
    • While the individual axon (nerve fiber) carries only one type of message, either motor or sensory, many of the nerves in the body are made up of both.
  • Causes of nerve injury
    • Nerves are fragile and can be damaged by pressure, stretching, or cutting.
      • Pressure or stretching injuries can cause the fibers carrying the information to break and stop the nerve from working, without disrupting the insulating cover. They may result in either temporary or permanent damage and require time to see if they will restore function. Unfortunately, because there is no direct laceration, there is typically no surgery that can be performed to improve the function with few exceptions.
      • When a nerve is cut, both the nerve and the epineurium are broken. These are recommended for surgery in order to directly repair of the cut and maximize the chances of restored sensation or function.
    • Injury to a nerve can stop the transmission of signals to and from the brain, preventing muscles from working and causing loss of feeling in the area supplied by that nerve.
    • Nerve injuries are often associated with injury to the surrounding soft tissue, bone, tendons, and arteries and should be thoroughly evaluated, typically in the operating room, to ensure all damaged structures are repaired. 
  • Repair & Recovery
    • To fix a cut nerve, the insulation around both ends of the nerve is sewn together using microsurgical techniques
      • A nerve in a finger is only 1-2 mm thick, thinner than a piece of thin spaghetti, so the stitches have to be very tiny and thin.
    • The repair will need to be protected with a splint for the first 3 weeks to protect it from stretching apart since it is so delicate. At that point, the scar tissue around the repair should prevent it from breaking apart with normal movement.
    • The goal in fixing the nerve is to repair the outer cover so that new nerve fibers can grow down the empty tubes, using the damaged nerve like a train track to find their way to the muscles and sensory receptors to work again.
    • Once the nerve cover is repaired, the nerve fibers generally begin to start growing across the repair site after three or four weeks. These then continue to grow on an average of 1 mm a day, or up to one inch every month, depending on the patient’s age and other factors.
      • This means that with an injury to a nerve in the arm 11 or 12 inches above the fingertips, it may take as long as a year before feeling returns to the fingertips.
    • The feeling of pins and needles in the fingertips is common during the recovery process. It is commonly described as a “burning” sensation, and can also include shooting pains from the site of injury all the way down to the fingertips.
      • While this can be uncomfortable, it usually passes and is a sign of recovery. There are also medications which can be prescribed to ease this discomfort during the healing process.

 

Fractures

A fracture is a broken bone and can range in size from being nearly imperceptible on an xray to being very obvious, displaced, or even shattered.

  • Symptoms
    • After sustaining a trauma, which could be falling, hitting your hand, slamming it in a door, punching a wall, etc, you may experience pain, swelling, bruising, discomfort with using your hand. 
  • Diagnosis
    • While there may be a high suspicion for a fracture based on exam alone, especially if the bones are displaced, an x-ray is needed to confirm the fracture and determine if surgery is needed for appropriate healing or if it can be managed nonoperatively.
  • Treatment
    • Most fractures are treated initially by setting the bone in the emergency department, then placing it into a splint to prevent additional movement which can impede healing.
    • Fractures that are displaced, unstable (will not stay in proper alignment), open (have a cut which exposed the bone to outside the skin), or involve a joint often require surgery to realign and stabilize the bone.
    • Pins, metal plates, and screws may be used to stabilize the fracture. What is used is determined by a variety of factors, including the patient’s age, other medical problems, and the exact type of injury.
    • Surgically repaired fractures will also remain in a splint or cast while healing occurs. The exception to this rule is when plates and screws are able to be used to stabilize the bone. While post-operative use of the hand will be limited, no splint is required and instead the patient is encouraged to move the hand into a fist starting the day after surgery. This is referred to as early motion, and is considered a strong benefit to being able to use plates as these patients have a much lower rate of stiffness and frequently require a shorter duration of therapy to return to full range of motion. For this reason, whenever possible, we prefer to plate using low-profile titanium hardware which is strong enough to hold the fracture in place, but thin enough to be hard to feel. We prefer this type of operation for it's optimal outcome. 
    • Hand Occupational Therapy is often used to improve range of motion, strength, and overall function after a fracture.

Dislocations

  • A dislocation refers specifically to angulation of a joint as a result of injury and may or may not be associated with a fracture. This angulation occurs when the ligaments that stabilize the bones into alignment are weakened, damaged, or completely ruptured due to a strong pulling force.
  • Diagnosis
    • Typically dislocations are easy to see on exam alone as the finger appears “crooked” at the involved joint.
    • In a less obvious dislocation, the joints can be tested for stability by pushing sideways on the affected bone. This may be associated with pain, movement, or a clicking sensation in many cases.
    • Xrays will be taken to confirm the diagnosis and assess for any associated fracture.
  • Treatment
    • Frequently, a dislocation can be reduced simply by pulling on the finger and rotating it back into place. Occasionally, however, there are complicating factors that prevent this from working appropriately and surgery will be necessary to adequately reduce the fracture.
    • Post-reduction xrays will be performed to ensure that the joint is realigned into its anatomical position.
    • Following a confirmed reduction, a splint is put into place and worn for 3 weeks to allow the ligaments to heal and provide stability to the joint again. After this, buddy-taping, where the finger is protected by taping it to the finger next to it, is performed for an additional 3 weeks to protect the finger while moving it.
    • Hand Therapy may be required if the patient develops stiffness to improve range of motion and long term function.

 

Amputations

  • An amputation is a complete separation of a part from the body, and can occur at any level in the hand and arm
  • Diagnosis:
    • Diagnosis is obvious on visualization of the injury, but x-ray is obtained to look at the extent of bony damage. There are two basic types of amputations:
      • Injury involving the soft tissue only and without exposed bone
        • Minor tissue injury
          • If the fingertip wound is small and not deep enough to expose bone, it may close on its own. Patients will be placed in a protective dressing and given specific instructions for care, typically to leave the dressing alone for several days. A splint will be used to protect the area as it heals.
          • Complete healing frequently takes upwards of 4-6 weeks.
        • Larger tissue injury
          • If the wound to your fingertip is large and open, there may not be enough remaining skin to heal and cover the open area.
          • If the wound is left to heal in on its own, the new skin can feel tight and scarred and may limit range of motion depending on the area of injury.
          • Skin grafting or alternative soft tissue coverage options such as local flaps are discussed and, based on your specific injury, will be recommended to optimize healing time and functional outcome.
      • Injury involving the soft tissue and WITH exposed bone
        • If the injury results in exposed bone, there may not be enough tissue around the wound to stitch it closed directly. When this happens, it is possible that the bone will need to be shortened to allow for wound closure.
        • Although this probably seems detrimental for long term use of the hand, most individuals with partial amputation injuries involving the fingers have excellent long term functional outcomes and use of their injured hand.
  • Treatment:
    • Although most people would prefer to have an amputated part reattached, or replanted, the location of the injury may make replantation impossible.
    • If replantation is not possible, other reconstructive surgery can be performed to preserve as much length as possible and improve function and appearance. However, shortening of the bone is sometimes required depending on the extent of damage to the skin and soft tissue around the injury and if there is enough tissue to adequately cover the bone and allow for healing.
    • A bulky dressing plus a full arm splint will be applied to the area initially after the procedure.
    • Full recovery including healing and any time required for hand therapy to restore full range of motion in the hand may take several months or longer depending on the exact location of the injury.
    • Close follow up is required to ensure adequate healing and return to function

 

Crush injuries

  • Soft tissue injury with painful swelling and bruising.
  • Can lead to compartment syndrome which is a surgical emergency

Fingertip injury

  • Injuries to the fingertips are common in accidents at home, work, and play. They can occur when a fingertip gets slammed in a car door, while chopping vegetables, or even when clearing debris from a lawnmower or snowblower.
  • Fingertip injuries can be crushing, tearing, or amputating injuries to the tips of fingers and thumbs. Injury can include damage to skin and soft tissue, bone (distal phalanx), or to the nail and nailbed. The tips of longer fingers tend to be injured more often because they are last to escape from harm's way.
  • Fingertips are rich with nerves and are extremely sensitive. Without prompt and proper care, a fingertip injury can disrupt the complex function of the hand, possibly resulting in permanent deformity and disability.
  • The goal of treatment is to have a pain-free fingertip that is covered by healthy skin. Your hand should be able to feel, pinch, and grip, and you should be able to perform normal hand functions. Your doctor will also try to preserve the length and appearance of your finger.
  • Specific treatment of a fingertip injury/amputation depends on the angle of the cut and the extent of the injury. Preservation of length as well as function and appearance of the finger are the main goals. 

 

Infections

Delayed or inadequate treatment can result in the progression of a simple process to a limb threatening or even life threatening situation.

  • Paronychia (Nailfold Infection)
    • Paronychial infections are a result of bacteria which are able to enter the tissue along the nail fold and become trapped, multiplying within the tissue.
    • These are the most common of hand infections and account for 10 to 20 percent of hand infections and may be caused by a variety of mechanisms:
      •  Hangnail, nail biting and frequent exposure to moisture are common contributing factors.
      • Dry cracked skin due to cold dry weather or detergents also can play a role.
    • Symptoms
      • As bacteria multiply, you may experience redness, swelling, pain, drainage, and difficulty moving.
    • Diagnosis
      • Diagnosis is clinical, based on appearance of the affected finger and the patients story, although xrays may be obtained to assess if there is any bone or joint involvement.
    • Treatment Options
      • In minor infections, gently probing the involved nailfold usually provides adequate drainage although removal of the nail plate is typically required to ensure complete drainage.
      • Daily soaks and oral antibiotics are recommended for several days.
  •  Herpetic Whitlow
    • Herpes simplex infection of the fingertip tissues which can mimic a paronychia.
    • Symptoms
      • Pain is usually severe, and tiny, clear fluid-filled blisters called vesicles form after the initial phase of swelling and redness.
    • Diagnosis
      • Viral cultures of the vesicle fluid confirm the diagnosis.
    • Treatment Options
      • Treatment is non-operative unless there is a secondary infection.
      • Antiviral drugs may shorten the several-day course of infection.
      • Latent infection may result in several recurrences over a period of weeks to months.
  • Felon
    • A felon is an infection or abscess of the fingertip pad.
    • Symptoms
      • Minimal trauma can provide an entry point for bacteria, usually staphylococcus aureus.
      • Swelling, redness, and intense pain develop.
    • Diagnosis
      • Based on clinical presentation and history, with the fingertip appearing red, swollen, and acutely tender.
    • Treatment Options
      • Making a cut over the point of maximal tenderness should allow for drainage and provide relief.
      • Warm soaks may or may not be required depending on the severity of the infection.
      • The infection typically resolves promptly after drainage in combination with appropriate antibiotics.
      • Long-term tenderness over the area of infection is a known possible complication of this type of infection.
  • Flexor Tenosynovitis
    • The flexor tendon sheath is a closed space containing synovial fluid. Bacteria introduced by direct trauma flourish in this space.
    • Symptoms and Diagnosis are based on exam
      • Kanavel's four classic signs of flexor tenosynovitis:
        • fusiform digital swelling (sausage finger)
        • semiflexed digital posture (finger slightly bent at rest)
        • pain with passive extension
        • tenderness over the flexor tendon sheath
    • Treatment Options
      • Surgical drainage and hospitalization for IV antibiotics are required for improvement.
      • Delays in treatment results in rapid spreading of the infection, which travels along the tendons spreading though the hand and into the forearm. If delayed too long, it can result in amputation of the finger, need for removal of one or more tendons, and long term pain and functional difficulty.
  • Bite Wound Infections
    • Animal and human bite wounds commonly occur on the hand. Deep penetration of a tooth covered with a variety of bacteria results in cellulitis and abscess formation.
    • Symptoms
      • Usually develop quickly and involve pain, redness, swelling, and can cause spreading redness away from the site of injury, which may result in
      • Treatment Options
        • Initial treatment should include irrigation and usually debridement of the puncture site, which involves enlarging of the initial wound to allow for adequate cleaning.
        • Antibiotics should be selected to cover both aerobic and anaerobic organisms.
        • Daily wound checks are necessary and hospitalization for IV antibiotics should be considered.
        • There is a low threshold for exploration and cleaning in the operating with bites in general, and may be recommended initially if the wound is directly over a joint.
  • Cellulitis and fasciitis
    • Generic term for any soft tissue infection and can range from non-suppurative cellulitis, meaning there is no pus or drainage, to aggressive necrotizing fasciitis, commonly known as “flesh-eating bacteria."
    • The severity of cellulitis is incredibly variable and may get better with oral antibiotics alone. Others require any combination of oral or IV antibiotics, wound drainage, warm soaks, or surgery.
    • Fascia is the tissue which lines and separates the various layers of tissue in the body. Fasciitis is a general term for inflammation of this layer, which can lead to pain or discomfort, one of the most common affected areas being plantar fasciitis in the foot.
    • In rare circumstances, necrotizing fasciitis can develop from even a superficial cut, when a variety of bacteria travel through an entrance down to the fascia and slide along this layer. Once here, the bacteria are able to spread rapidly along the plane, killing the soft tissue as it travels and causing limb and life-threatening infections in very little time, usually within just a few days of developing the infection.
    • Treatment Options
      • Treatment of these infections range from oral antibiotics in simple cases to IV antibiotics in combination with a series of aggressive life-saving surgical debridement’s, several days in the hospital with possible time in the ICU, and reconstruction of the affected area.
      • Treatment of these hand infections does not differ from treatment of infection in other areas of the body.