What’s Kienbock’s disease and just how could it be caused?

MNT Knowledge Center

Kienbock’s disease, also known as avascular necrosis of the lunate, occurs when one of the eight small carpal bones in the wrist – the lunate bone – becomes damaged because its blood supply is lost.

Kienbock’s disease is really a rare, debilitating disease procedure that can result in chronic discomfort and disorder.

Within the Journal of Hands Surgery1, avascular necrosis from the lunate can also be known to as “osteonecrosis from the lunate”.

Avascular necrosis means dying, damage or fracture of navicular bone because of interruption of bloodstream supply.

With no sufficient bloodstream supply, bone dying or damage (osteonecrosis) can happen.

Robert Kienb?ck (1871-1953), an Austrian radiologist and pioneer in using x-ray technology for medical diagnosis and therapy, described a problem where the lunate bone within the wrist would break lower.

Kienb?ck known as the disorder “lunatomalacia”. He printed his findings inside a dissertation entitled “Distressing malacia from the lunate and it is effects” (über traumatische Malazie plusieurs Mondbeins und ihre Folgezust?nd). The disorder was later known as “Kienbock’s disease”.

The condition might be typed “Kienb?ck’s” or “Kienbock’s”.

The carpal bones in the wrist

In Kienbock’s disease among the carpal bones – the lunate – becomes broken.

The carpal bones contain eight wrist bones that connect the hands towards the forearm. These bones facilitate flexible positioning from the hands.

The Lunate is among the 8 bones within the carpus

The lunate bone is vital for correct movement and support from the joint.

When the lunate bone is broken, the individual can experience stiffness and discomfort, and finally joint disease from the wrist.

What are the signs and symptoms of Kienbock’s disease?

Based on the National Institutes of Health2, initially, affected people may question when they have been sprained their wrist. However, within the situation of Kienbock’s disease the twelve signs and signs and symptoms don’t disappear – it’s a progressive disease.

Kienbock’s disease progresses in a different way from patient-to-patient. Generally, it evolves gradually and subtly during a period of a long time.

Initially, the individual might only experience discomfort and swelling. Afterwards the mechanics from the wrist become affected. This places abnormal stresses and put on within the wrist.

Based on the American Society for Surgery from the Hand3, Kienbock’s illnesses has four stages:

  • Stage 1 – the lunate has lost its blood supply. However, x-rays are unable to detect anything abnormal with the affected bone. There is some pain, possibly some swelling as well, and a risk of fracture.
  • Stage 2 – x-rays show that the bone is unusually dense. When bone loses its blood supply it hardens.
  • Stage 3 – the bone starts to shatter (fragments and collapses).
  • Stage 4 – the lunate has completely collapsed. The other bones next to the lunate have also become damaged and arthritic. No all patients reach this stage.

The following signs and symptoms are common in Kienbock’s disease:

  • swollen wrist
  • painful wrist
  • stiffness in the wrist – the range of motion becomes progressively limited
  • clicking or clunking in the wrist
  • weaker grip strength
  • tenderness directly over the lunate bone
  • difficulty in turning the hand upward
  • pain when trying to turn the hand upward

What are the causes of Kienbock’s disease?

Experts believe Kienbock’s disease does not have a single cause, and is the result of multiple factors.

According to Massachusetts General Hospital4, the following factors are associated with a higher risk of developing Kienbock’s disease:

  • Problems with blood supply (arteries). Most of us have two blood vessels supplying blood to the lunate bone. However, in some cases there is just one source.
  • Problems with blood drainage (veins).
  • Skeletal variations – possibly the lunate bone has an abnormal shape. The ulna, one of the bones in the forearm may be shorter than normal. If the ulna and radius bones are different lengths there may be extra pressure on the lunate in certain wrist motions – this extra stress could eventually lead to Kienbock’s disease.
  • Some diseases may be linked to a greater risk, including lupus, cerebral palsy, sickle cell anemia and gout. One study found that 9.4% of cerebral palsy patients also had Kienbock’s disease5.
  • Trauma – blood supply may have been affected by a single blow, as in a car accident, or “repeated significant trauma”.
  • There is no compelling evidence suggesting that certain jobs may increase the risk of developing Kienbock’s disease

How is Kienbock’s disease diagnosed?

Most sufferers are not equipped to determine a physician before the signs and symptoms start bothering them. In nearly all cases, what this means is they’ve been coping with the progressive disease for many several weeks, as well as years.

Most sufferers will initially typical to wrist discomfort.

The physician asks questions regarding the signs and symptoms, health background, whether there’s been any serious trauma, and just how lengthy signs and symptoms happen to be present.

A person’s hands and wrist is going to be examined.

Initially, Kienbock’s disease might be hard to identify precisely, because its signs and signs and symptoms act like individuals present in a number of other conditions, for example wrist sprain and then any reason for joint disease.

Even x-ray imaging during Stage one of the disease can have an allegedly normal lunate bone.

Magnetic Resonance Imaging (MRI) might help the physician measure the bloodstream supply towards the lunate. CT (calculated tomography) checking can be utilized in later stages to look for the number and dimensions from the lunate fragments.

Even when the x-ray doesn’t show any bone abnormality and also the physician doesn’t order further MRI or CT scans, the x-sun rays will later get the twelve signs once the bone begins to harden6 and lose its mineral content.

What are the treatment options for Kienbock’s disease?

Treatment usually depends on how early on the disease is diagnosed.

Non-surgical options for Kienbock’s disease

Resting the wrist – if it is diagnosed early enough, it might be possible to splint and cast the wrist for several weeks. Resting the wrist increases the likelihood of restoring blood flow to the lunate bone. However, this is only an option during Stage 1.

Anti-inflammatory drugs, such as ibuprofen or aspirin may help manage the symptoms of swelling and pain during the early stages.

Wrist injection with a cortisone type solution may also help symptoms.

Close monitoring of symptoms is important during Stage 1. If OTC (over-the-counter, no prescription required) anti-inflammatory medications start becoming less effective, the doctor may recommend surgery.

A specialized physical therapist can teach the patient “activity modification” – how to use the wrist in a way that is less painful and slows down the progression of the disease.

Surgical procedures for Kienbock’s disease

There are several different surgical procedures available for patients with Kienbock’s disease. Which one chosen to recommend will depend on several factors. According to the American Academy of Orthopaedic Surgeons7, these options usually depend on the stage of the disease, the patient’s level of activity, the patient’s personal goals and how experienced the surgeon is.
External fixator used in orthopaedic surgery

  • Revascularization – this means either restoring or augmenting the blood supply, which in this case is to the lunate bone.

Revascularization is an option during Stages 1 and 2, before the bone has deteriorated significantly.

The surgeon removes a portion of bone with all its attached blood vessels from another bone and inserts it into the lunate bone.

The portion of bone with that is attached is called a “vascularized graft”.

The surgeon may temporarily apply an external fixator to make sure the bones stay in place while they heal. An external fixator is a metal device which is attached to the outside of the wrists, with pins that insert into the bone.

 

  • Joint leveling – an option when the two bones – radius and ulna – of the forearm have different lengths. Either bone grafts are applied to lengthen bone, or a section of bone is removed to shorten it.

 

Joint leveling often stops the disease from progressing by reducing the forces that compress the lunate bone.

 

  • Proximal row carpectomy (PRC) – the removal of the lunate bone. An option if the bone is broken into pieces or severely collapsed. The surgeon also removes the two bones on either side of the lunate.

 

The Hand and Wrist Center of Houston8, Texas, explains the pros and cons of PRC. Advantage – PRC is straightforward surgical procedure. Disadvantage – “The two new bones that rub together do not match and arthritis develops where they make contact.”

 

  • Fusion – this can be partial or complete fusion. In partial fusion some of the wrist bones are fused together, effectively becoming one solid bone. The aim here is to reduce symptoms of pain and maintain some wrist motion.

 

When the patient has severe joint disease from the wrist, the physician may recommend fusing all of the bones. The end result is going to be significantly less discomfort and hands function. Despite the fact that wrist motion is going to be completely lost, the individual continues to be in a position to rotate the forearm.

Once the bones are fused, the end result can last for that relaxation from the patient’s existence.

 

  • Implant arthroplasty – the lunate bone is replaced with a prosthetic replica made of a special, durable, pyrolytic carbon material.

 

Based on the Hands and Wrist Center of Austin, this process preserves the standard anatomy of all of the others bones.

Because this procedure is comparatively new within this area of the body, nobody knows exactly what the lengthy-term outcomes of laser hair removal are.

Some patients may undergo a number of different methods throughout their lifetime. Possibly beginning served by casting, a bone graft, radial shortening, proximal row carpectomy and lastly wrist fusion.

What are the complications associated with Kienbock’s disease?

If not treated, the individual are experiencing progressive degeneration from the wirst, lack of wrist function and growing discomfort.

Between Stages 2 and 4 from the disease, grip strength deteriorates by 40%.

Scientists from Shinshu College Med school, Japan, authored within the Scandinavian Journal of Plastic and Rebuilding Surgery and Hands Surgery9 that “Closed tendon rupture is really a well-known complication of Kienbock disease.”