Monday, October 12, 2009

Osteomyelitis of Long Bones

Osteomyelitis is defined as infection in bone. Osteomyelitis in long bones includes infections that differ from one another with regard to duration, etiology, pathogenesis, extent of bone involvement, and type of patient (which can be an infant, child, adult, or compromised or uncompromised host).

In hematogenous osteomyelitis, a single pathogenic organism is almost always recovered from the bone. In infants, Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli are most frequently isolated from blood or bone.

However, in children over one year of age, Staphylococcus aureus, Streptococcus pyogenes, and Haemophilus influenzae are most commonly isolated. The incidence of Haemophilus influenza infection decreases after the age of four years.

In adults, Staphylococcus aureus is the most common organism isolated. Multiple organisms are usually isolated from bone infected as a result of direct inoculation or contiguous focus infection. Staphylococcus aureus remains the most commonly isolated pathogen. However, gram-negative bacilli and anaerobic organisms are also frequently isolated.


1. Source of Infection

Osteomyelitis can be caused by hematogenous spread, direct inoculation of microorganisms into bone, or a contiguous focus of infection. Hematogenous osteomyelitis usually involves the metaphysis of long bones in children because long bones of children have very active metabolic rates. The most common causes of direct-inoculation osteomyelitis are penetrating injuries and surgical contamination. Contiguous osteomyelitis commonly occurs in patients with severe vascular disease.

2. Host Factors

Host factors are primarily involved in the containment of the infection once it has been introduced adjacent to or into the bone. Host factors may predispose individuals to the development of osteomyelitis. Host deficiencies that lead to bacteremia favor the development of hematogenous osteomyelitis.

Host deficiencies that are involved in the direct inoculation of organisms and/or contiguous spread of infection from an adjacent area of soft-tissue infection are primarily involved in the lack of containment of the initial infection.

Some patients have an unusual susceptibility to acute skeletal infections when they have sickle cell anemia, chronic granulomatous disease, or diabetes mellitus. Many systemic and local factors influence the ability of the host to elicit an effective response to infection and treatment


1. Acute Osteomyelitis

Acute osteomyelitis presents as inflammation accompanied by edema, vascular congestion, and small-vessel thrombosis. In early acute disease, the vascular supply to the bone is decreased by infection extending into the surrounding soft tissue. When both the medullary and the periosteal blood supplies are compromised, large areas of dead bone (sequestra) may be formed in chronic phase.

However, if treated promptly and aggressively with antibiotics and possibly with surgery, acute osteomyelitis can be arrested before dead bone presents.

2. Chronic Osteomyelitis

Pathologic features of chronic osteomyelitis are the presence of necrotic bone (sequestrum), the formation of new bone (involucrum), and the exudation of polymorphonuclear leukocytes joined by large numbers of lymphocytes, histiocytes, and occasionally plasma cells.

New bone forms from the surviving fragments of periosteum and endosteum in the region of the infection. It forms an encasing sheath of live bone, known as an involucrum, surrounding the dead bone under the periosteum.

The involucrum is irregular and is often perforated by openings through which pus may track into the surrounding soft tissues and eventually drain to the skin surfaces, forming a chronic sinus. The involucrum may gradually increase in density and thickness to form part or all of a new diaphysis.

New bone increases in amount and density for weeks or months, according to the size of the bone and the extent and duration of the infection. Endosteal new bone may proliferate and obstruct the medullary canal. After host defense or operative removal of the sequestrum, the remaining cavity may fill with new bone, especially in children. However, in adults, the cavity may persist or the space may be filled with fibrous tissue, which may connect with the skin surface by means of a sinus tract.

Views of the left wrist show a lobulated osteolytic lesion with well-defined borders and surrounding sclerosis in the distal radius. There were minimal expansion, mild periosteal reaction and soft tissue swelling.

Views of the left wrist show a lobulated osteolytic lesion with well-defined borders and surrounding sclerosis in the distal radius. There were minimal expansion, mild periosteal reaction and soft tissue swelling.

The red box encircles the sequestrum at lower part of tibia, the piece of necrotic tissue of tibial bone, that has become separated from the tibia

The red box encircles the sequestrum at lower part of tibia, the piece of necrotic tissue of tibial bone, that has become separated from the tibia

Signs and Symptoms

Children with hematogenous osteomyelitis may present with acute signs of infection including fever, irritability, lethargy, and local signs of inflammation. Children with hematogenous osteomyelitis usually have noninfected soft tissue enveloping the infected bone and are capable of mounting an effective response to the infection. The joint is usually spared from infection unless the metaphysis is intracapsular, as is found in the proximal part of the radius, humerus, or femur.

Adults with primary or recurrent hematogenous osteomyelitis usually present with vague symptoms consisting of nonspecific pain and low-grade fever of one to three months’ duration. However, acute clinical presentations with fever, chills, swelling, and erythema over the involved bone or bones are occasionally seen.

The source of bacteremia may be a trivial skin infection or a more serious infection such as acute or subacute bacterial endocarditis. Hematogenous osteomyelitis that involves either long bones or vertebrae is an important complication of injection drug abuse. Patients with contiguous osteomyelitis often present with localized bone and joint pain, erythema, swelling, and drainage around the area of trauma, surgery, or wound infection.

Signs of bacteremia such as fever, chills, and night sweats may be present in the acute phase of osteomyelitis but are not seen in the chronic phase. Both hematogenous and contiguous focus osteomyelitis can progress to a chronic condition. Local bone loss, sequestrum formation, and bone sclerosis are common. Persistent drainage and/or sinus tracts are often found adjacent to the area of infection. The patient usually presents with chronic pain and drainage. If fever is present, it is low grade.

External Fixation

Case summary

36 y/o, Malay gentleman

Patient drove car with around 60km/h and was crashed with lorry from front. He was loss of consciousness and was sent to emergency department by ambulance. Multiple fractures and bleeding were noted. There was an open fracture of right leg, grade 3C in Gustillo classification. X-ray of the right leg was done.

Plain x-ray of the right leg.

AP view of tibial plateau #This is an anterior-posterior view of distal 1/3 of right knee and proximal 2/3 of right leg. The x-ray showed that there is segmented fracture of tibial plateau, both condyles are split and the tibial shaft is wedged between them, there is intraarticular extended and was type 5 in Schatzker classification. There is no shortening, angulation or rotation of the bone was seen in this view.

Lateral view of tibial plateau #This is a lateral view of distal 1/3 of right knee and proximal 2/3 of right leg. The x-ray showed that there is segmented fracture of tibial plateau, There is 10 degree angulation of the tibial bone.There is no shortening or rotation of the bone was seen in this view.

External fixation was done.

AP view of x-ray after external fixationThis is an anterior-posterior view of distal 1/3 of right knee and proximal 2/3 of right leg. The x-ray showed that there is a interfragmentary screw fixing the fragmented tibial bone. Two pins were passed though th femur bone and another two pins were passed through the tibial bone. There is no angulation, shortening or rotation seen in this view.

lateral view of x-ray after external fixationThis is a lateral view of distal 1/3 of right knee and proximal 2/3 of right leg. The x-ray showed that there is an interfragmentary screw on the fragments. there is no angulation, shortening and rotation of the bone was seen in this view.

External fixation is a surgical treatment which is held by transfixing screws, pins or tensioned wires which are pass through the bone above and below of the fracture site. These are then connected to an external frame or rigid bar. While reducing the fracture in all three planes, hold it in the proper alignment (adjustment of the angulation), it also allow some degree of rigidity and stability. besides it also allow adjustment of length of the bone. External fixation is commonly apply to fracture of long bones (esp. femur, tibia and humerus) and pelvic, but it can also be used for fractures of almost any part of the skeleton (example bone of the hand). Insertion of wires and half pins must be with care, by the knowledge of 'safe corridors' is to avoid nerves or vessels injury.

Indications of external fixation include:

1. Fracture associated with severe soft tissue damage.

external fixation for wound inspectionexternal fixation was apply, two pins on the femur bone and two pins on the tibia bone. there are two wounds on the anterior aspect of upper half leg. The wound is measuring 5x3cm and 5x4cm. There is bleeding, no slough, granulation tissue present, slope well-defined edge. There is no maculous pin-site infection.

2. Fracture associated with nerve and vessel damage.
3. Severely comminuted and unstable fracture
4. Non-union where dead or sclerotic fracture fragment can be excised and fragments brought together by fixator
5. Fracture of pelvic which cannot be held by other method
6. Infected fracture
7. Severe multiple injuries


1. Damage to soft tissue structures.
Surgeon must familiar with the anatomy and the 'safe corridor' to prevent injured to the nerves and vessels.

2. Overdistraction.
Fragments of the bone must come to contact for union to be occur. If there is no contact between of the fragments, union may be delayed or prevented.

3. Pin-track infection.
This is rare but is the most complicated. Therefore, meticulous pin-site care is essential. If infection is occur, administered of antibiotics must be immediate.

Type 2 Diabetes Mellitus and its related foot complications in Malaysia

Incidence of Type 2 Diabetes Mellitus in Malaysia:

In Malaysia, the First National Health and Morbidity Survey (NHMS 1) conducted in 1986 reported a prevalence of diabetes mellitus of 6.3% [1]. In the Second National Health and Morbidity Survey (NHMS 2) in 1996, the prevalence had risen to 8.3% [2]. The prevalence of diabetes had increased drastically to 14.9 per cent in 2006 for the same age group; an increase of 80% based on the Third National Health and Morbidity Survey 2006 (NHMS 3) [3]. Currently, it is estimated that one out of eight Malaysians aged 30 years and above has diabetes, which amounts to over 1.6 million adults in Malaysia. The World Health Organisation (WHO) has estimated that in 2030, Malaysia would have a total number of 2.48 million diabetics compared to 0.94 million in 2000 - a 164% increase.

Incidence of foot related complications:

Foot ulceration associated with infection is one of the leading causes of hospitalization patients with diabetes mellitus. Approximately 15% of all patients with diabetes will develop a foot or leg ulceration at some time during the course of their disease.[1-3]

Several population-based studies report an annual incidence of diabetic foot ulceration in the range of 2% to 3% in patients with either Type 1 or Type 2 diabetes, while the prevalence varies between 4% and 10%

Numerous risk factors for diabetic foot ulceration have been ascertained. Aside from the major factors of neuropathy, ischemia, pressure (trauma), and infection, multiple other contributory factors interact to produce foot lesions. Intrinsic risk factors include metabolic or biologic characteristics that may or may not be causally related to diabetes but do contribute to the aetiology of ulceration.

Symptom of diabetes:

48% of patients above the age of 30 years old are not aware that they have diabetic. The majority are asymptomatic. Patients should be aware of common symptoms of diabetes which include polyuria (increased frequency of urination), polydipsia (increased thrist), easily tired and sudden unexplained weight loss [4].

Classification diabetic foot complications
Diabetic Foot Problems are best classified according to King’s Classification [5].
Stage 1: Normal
Stage 2: High Risk
Stage 3: Ulcerated
Stage 4: Cellulitic Stage
Stage 5: Necrotic
Stage 6: Major Amputation


Post Ray’s amputation+ incision and drainage

The surgical wound located at the dorsal surface of the right foot. The wound bed consists of granulation tissues and slough. This is not a well-healing wound.

The surgical wound located at the dorsal surface of the right foot. The wound bed consists of granulation tissues and slough. This is not a well-healing wound.


Glycosylated hemoglobin level must be taken to obtain information of the patient’s glucose control over the past 3 months. This investigation is based on the fact that in the normal 120 day life span of the red blood cell, excess glucose molecules will react with hemoglobin, forming glycosylated hemoglobin. In individuals with poorly controlled diabetes, the level of glycosylated hemoglobins will be elevated.

Plain radiograph of foot and ankle can also be taken to make sure there is no involvement of bone to rule out osteomyelitis.

Doppler ultrasound also is significant to investigate the peripheral circulation of foot to prevent ischemia.

Diabetic Foot Care Treatment

Self-Care at Home

A person with diabetes should do the following:

  • Foot examination: Examine your feet daily and also after any trauma, no matter how minor, to your feet. Report any abnormalities to your physician. Use a water-based moisturizer every day (but not between your toes) to prevent dry skin and cracking. Wear cotton or wool socks. Avoid elastic socks and hosiery because they may impair circulation.
  • Eliminate obstacles: Move or remove any items you are likely to trip over or bump your feet on. Keep clutter on the floor picked up. Light the pathways used at night - indoors and outdoors.
  • Toenail trimming: Always cut your nails with a safety clipper, never a scissors. Cut them straight across and leave plenty of room out from the nailbed or quick. If you have difficulty with your vision or using your hands, let your doctor do it for you or train a family member how to do it safely.
  • Footwear: Wear sturdy, comfortable shoes whenever feasible to protect your feet. To be sure your shoes fit properly, see a podiatrist (foot doctor) for fitting recommendations or shop at shoe stores specializing in fitting people with diabetes. Your endocrinologist (diabetes specialist) can provide you with a refferel to a podiatrist ororthopedist who may also be an excellent resource for finding local shoe stores. If you have flat feet, bunions, or hammertoes, you may need prescription shoes or shoe inserts.
  • Exercise: Regular exercise will improve bone and joint health in your feet and legs, improve circulation to your legs, and will also help to stabilize your blood sugar levels. Consult your physician prior to beginning any exercise program.
  • Smoking: If you smoke any form of tobacco, quitting can be one of the best things you can do to prevent problems with your feet. Smoking accelerates damage to blood vessels, especially small blood vessels leading to poor circulation, which is a major risk factor for foot infections and ultimately amputations.
  • Diabetes control: Following a reasonable diet, taking your medications, checking your blood sugar regularly, exercising regularly, and maintaining good communication with your physician are essential in keeping your diabetes under control. Consistent long-term blood sugar control to near normal levels can greatly lower the risk of damage to your nerves, kidneys, eyes, and blood vessels.

Medical Treatment

  • Antibiotics: If the doctor determines that a wound or ulcer on the patient’s feet or legs is infected, or if the wound has high a risk of becoming infected, such as a cat bite, antibiotics will be prescribed to treat the infection or the potential infection. It is very important that the patient take the entire course of antibiotics as prescribed. Generally, the patient should see some improvement in the wound in two to three days and may see improvement the first day. For limb-threatening or life-threatening infections, the patient will be admitted to the hospital and given IV antibiotics. Less serious infections may be treated with pills as an outpatient The doctor may give a single dose of antibiotics as a shot or IV dose prior to starting pills in the clinic or emergency department.
  • Referral to wound care center: Many of the larger community hospitals now have wound care centers specializing in the treatment of diabetic lower extremity wounds and ulcers along with other difficult-to-treat wounds. In these multidisciplinary centers, professionals of many specialties including doctors, nurses, and therapists work with the patient and their doctor in developing a treatment plan for the wound or leg ulcer. Treatment plans may include surgical debridement of the wound, improvement of circulation through surgery or therapy, special dressings, and antibiotics. The plan may include a combination of treatments.
  • Referral to podiatrist or orthopedic surgeon: If the patient has bone-related problems, toenail problems,corn and callus hammertoes, bunions, flat feet, heel spurs, arthritis, or have difficulty with finding shoes that fit, a physician may refer you to one of these specialists. They create shoe inserts, prescribe shoes, remove calluses and have expertise in surgical solutions for bone problems. They can also be an excellent resource for how to care for the patient’s feet routinely.
  • Home health care: The patient’s doctor may prescribe a home health nurse or aide to help with wound care and dressings, monitor blood sugar, and help the patient take antibiotics and other medications properly during the healing period.


1. National Health and Morbidity Survey 1986

2. National Health and Morbidity Survey 1996

3. National Health and Morbidity Survey 2006

4. Mafauzy M. Diabetes Mellitus in Malaysia. Medical Journal of Malaysia. 2006.

5. Edmonds ME and Foster AVM. Managing the diabetic foot, 2nd ed. (Blackwell, London, 2005).

Malaysia endocrine and metabolic society,Ministry of health,acdemic of medicine malaysia,Persatuan diabetic malaysia.

Saturday, September 12, 2009

Bionic brain chips could overcome paralysis

By Sunny Bains

A MONKEY sits on a bench, wires running from its head and wrist into a small box of electronics. At first the wrist lies limp, but within 10 minutes the monkey begins to flex its muscles and move its hand from side to side. The movements are clumsy, but they are enough to justify a rewarding slug of juice. After all, it shouldn't be able to move its wrist at all.

A nerve connection in the monkey's upper arm had previously been blocked with an anaesthetic that prevented signals travelling from its brain to its wrist, leaving the muscles temporarily paralysed. The monkey was only able to move its arm because the wires and the black box bypassed the broken link.

The monkey was in Eberhard Fetz's lab at the University of Washington in Seattle. The experiment, performed last year, was the first demonstration of a new treatment that might one day cure paralysis, which is typically caused by a broken connection in the spinal cord. Though much work has focused on using stem cells to regrow damaged nerve fibres, some researchers believe that an electronic bypass like this is equally viable.

The idea is to implant electronic chips in the relevant regions of the brain to record neural activity. Then a decoder deciphers the neural chatter, often from thousands of neurons, to figure out what the brain wants the body to do. These messages must then be relayed - ideally wirelessly - to electrodes that deliver a pulse of electricity to stimulate the muscles into action. Such "brain chips" are already restoring hearing to the deaf and vision to the blind, and helping to stave off epileptic fits, so the idea isn't as far-fetched as it might sound (see "Bionic medicine").

Every step of progress in tackling paralysis has been hard won. One of the early demonstrations that it may be possible emerged in 2003, when José Carmena, then at Duke University in Durham, North Carolina, successfully created an interface between brain and machine that allowed his lab monkeys to play a computer game using only their minds.

To gain a juice reward, the monkeys had to move a cursor - initially with a joystick - to hit a target on the computer screen. Beforehand, Carmena and his colleagues had implanted several chips throughout the parietal and frontal lobes of the monkeys' brains - regions known to plan and control movement. Each chip held up to 64 electrodes, which recorded the firing of the surrounding neurons as the monkeys manipulated the joystick.

Once the system had successfully decoded the chatter from the monkeys' neurons, the program stopped responding to the joystick's movement altogether and relied solely on the monkeys' thoughts to control the cursor. Eventually even the animals worked this out and stopped holding the joysticks as they completed the task (PLoS Biology, vol 1, p 42).

Manipulating a cursor on a computer screen is one thing, but whether such brain chips could translate the more complicated tasks of daily life remained an open question until 2004, when John Donoghue and colleagues from Cyberkinetics in Providence, Rhode Island, implanted a 100-electrode chip in the brain of a 25-year-old man known as MN, who had been left paralysed from the neck down by a knife wound.

Over the subsequent nine months, MN successfully used this BrainGate chip to open emails, operate a television and even control a robotic arm (Nature, vol 442, p 164). It was a promising step, but the technology was far from perfect. "Although BrainGate1 worked well in many ways, at times the control was not satisfactory," says Donoghue. And by the end of the trial, fluids from the brain had degraded the chip. The team are now solving these problems, and earlier this year announced the start of a clinical trial for an improved version of the chip.

With a chip implanted in his brain, a paralysed man was able to open emails, operate the TV and even control a robotic arm

The ultimate hope for many paralysed people, of course, is to regain movement in their own limbs. Until Fetz's experiment last year, no one had successfully used an implant to bridge a broken connection between the brain and the body. Trials of functional electrical stimulation (FES), in which implanted electrodes directly stimulate muscles into action, had hinted that this might be possible. But these impulses had been activated by external triggers, such as a switch controlled by one of the patient's healthy limbs, and not directly by brain signals.

Not only did Fetz's work demonstrate that the electronics could descramble neural signals and relay appropriate instructions to the limbs using FES, he also showed that the brain makes the job easier than one might expect. Although the motor neurons that connected to the chip did not naturally control the wrist, in a short time they adapted to the task and controlled complex actions (Nature, vol 456, p 639). "All neurons could be used equally well for control regardless of their original association to movement," says team member Chet Moritz.

That could have an important implication for humans hoping to use similar implants in the future. "It underscores the impressive flexibility of the brain in learning to adapt to novel connections, which may play a key role in allowing neural prostheses to be adopted by patients," he says.

So could the same approach work in humans? There seem to be no fundamental obstacles, and Donoghue plans to test the proposition in the new BrainGate trials, using his chip to control a limb using FES. If successful, it will represent a milestone in the development of such treatments.

Direct electrical stimulation of muscles using FES is unlikely to be the final solution, however. This direct approach uses a relatively powerful electric current applied to large areas of tissue, producing fairly clumsy movements. A more elegant method, some claim, is to send the impulse along the existing healthy nerves. That would require smaller local currents, delivered with greater precision, to finer regions of the muscle tissue, which should allow more subtle control.


As a bonus, nerve stimulation could simplify some of the demands placed on a brain chip. That's because for many rhythmic activities, such as breathing, walking and crawling, the brain simply sends a command signal and it is the spinal cord's in-built systems that orchestrate the fine movements of each muscle. So if the healthy sections of a damaged spinal cord have retained their ability to control movement, the electronic chip could transmit the brain signal around the broken connection but leave the muscular orchestration to the spinal cord. In this case, a brain chip would just beam the message to a second device implanted in the spine below the break, which would then stimulate the spinal cord.

The chips could simply transmit the information around the break, leaving the undamaged sections of the spinal cord to orchestrate the muscles

That could "dramatically simplify the control signals needed from the brain", says Moritz, since for these repetitive tasks the brain chip would just decode and transmit an umbrella command. Such simplification should make the chips less likely to fail - an important consideration when the only way to replace the chips is through invasive surgery - and also reduce their power consumption.

Using this principle in 2002, Vivian Mushahwar, now at the University of Alberta in Edmonton, Canada, plugged four electrodes into a cat's spinal cord and delivered signals that mimicked the brain's command to walk. Sure enough, the cat made stepping motions.

Simply relaying the messages across a break in this way would not help the worst injuries, however, in which the spinal cord has lost its ability to coordinate muscles. In these cases, to minimise the size of the brain chip, and the burden placed on it, the muscular orchestration would need to come from either the chip implanted in the spinal cord, or an external device that communicates wirelessly with the chips in the brain and the spine.

Calculating exactly which nerves to stimulate and in what pattern is no easy task, but the first demonstration of an artificial "central pattern generator" was reported last year, when Mushahwar and colleagues at Johns Hopkins University in Baltimore, Maryland, successfully tested such a chip on a cat. With coordination coming solely from an external CPG chip connected to a handful of electrodes that stimulated the cat's spine, the animal was able to walk (IEEE Transactions on Biomedical Circuits and Systems, vol 2, p 212). In this experiment, the team were simply testing the CPG's ability to orchestrate movement as an alternative to FES, so the trigger came from a manual switch and not the cat's brain. The next hurdle will be to use the CPG in conjunction with a neural chip.

While this CPG chip only dealt with the action of walking, in humans an additional external chip might also offload some of the processing from the brain chip for non-repetitive motions like clenching a fist or raising a hand. The brain doesn't necessarily produce an umbrella command for all of these movements, so the neural implant would still need to detect a more complicated signal, but the external chip could at least perform some of the processing to decode and relay these comands to the relevant electrodes.

For many patients, technology like this would only solve half the problem, however. Paralysed people who have lost feeling as well as movement in their limbs would need two-way systems to pass sensations back to their brain. This information could come from artificial sensors, but ideally the chip would read sensations from existing nerves and relay them to chips that stimulate the areas of the brain that process tactile information.

Although work has been slower in this area, there's good evidence it will one day be possible. Carmena, for instance, who is now at the University of California, Berkeley, recently stimulated a rat's brain to feel sensations from some "virtual whiskers", causing it to move as if its own whisker's had really brushed against an object. Similar technology could one day relay tactile information to the human brain.

If these advances in brain-chip capability are to be exploited, the researchers still need to ensure that the chips are safe and durable. Biocompatibility, for instance, is a huge challenge, because tissue in the brain can react badly to an implant, killing off the very neurons that the electronics are trying to connect to. Recent efforts suggest a coating of growth hormones might mitigate this problem, while others have shown chips that slowly exude stem cells might also work.

Then there's the problem of powering the devices. Most existing implants - like cochlear implants, for example - are connected to a battery outside the head that can be replaced regularly. The electrodes in the spine and limbs could be powered this way, but it's less practical for a chip deep within the skull. Instead, such chips will need to be recharged by electromagnetic fields generated by a device outside the head, so power consumption will have to be minimal.

One solution might be to offload the more difficult processing to a portable computer outside the body, before passing the information back to the chips that stimulate the nervous system. In this way, Reid Harrison at the University of Utah in Salt Lake City has produced a neural chip that uses just 8 milliwatts. That's less than the "standby" LED on the front of a TV set.

Security risks

All the pieces are gradually coming together, but whatever happens it will be a long time before these chips can become a mainstream treatment: the US Food and Drug Administration requires as much as 10 years of animal testing before a chip can be deemed safe enough to be implanted in human brains. That means the latest technology, such as chips that stimulate tactile sensations in the brain, will need extensive testing before clinical trials can begin.

Yet even once the technology has proven itself, the social issues surrounding the treatment will need to be solved. Take the question of security, for example. Last year, a team of researchers successfully hacked into a heart pacemaker and defibrillator through the wireless communication that allows doctors to adjust its performance. Although the device wasn't implanted in anyone at the time, it raised the possibility that hackers could disrupt a patient's treatment (New Scientist, 22 March 2008, p 23).

To make matters worse, there is currently no obvious way of protecting a defibrillator or pacemaker from a hacker without inhibiting a doctor from accessing it during an emergency. Since neural prostheses will rely so heavily on wireless links to communicate between the different components, the risk to these chips may be even greater.

Perhaps most perplexing is the question of legal responsibility. If someone wearing a neural prosthesis were to punch someone, who is to blame? The action may have been deliberate, in which case the patient is to blame, or the chip may have been malfunctioning and the responsibility would lie with the manufacturer. Discovering where the truth lay would be no easy task. The law has had trouble catching up with the self-parking car, never mind an electronically controlled limb gone wild.

Bionic medicine

Paralysis is not the only condition that can be treated with chips in the brain


The cochlear implant has been commercially available for many years. It detects sound and creates a signal that is fed directly into the auditory nerve. In this way, damaged portions of the ear can be bypassed entirely.


Retinal prostheses are being tested in blind people who lack the ability to turn light signals into neural signals. They can be plugged into the brain either at the retina itself, the optic nerve, or even the visual cortex.

Parkinson's disease

Some people with Parkinson's are implanted with deep brain stimulation systems that can prevent some of the shaking that is characteristic of the disease. Though the surgery carries risks, a new study shows that people gained more than 4.5 "good" hours a day using the devices (The Journal of the American Medical Association, vol 301, p 63).


Devices known by some as "brain pacemakers" send regular electrical pulses to parts of the brain associated with the condition, helping to prevent the neurons from firing in the patterns associated with seizures.

Sunny Bains is a science journalist based in London

Diabetic foot team lowers rate of major amputations

Incidence of major diabetic foot amputations decreased 41% in 10 years.

By Gina Brockenbrough

Norwegian investigators discovered a significant decrease in the incidence of diabetic foot amputations in one town 10 years after the establishment of a diabetic foot team at the city’s only hospital.

“We have registered a 41% decrease in major diabetic amputations,” Eivind Witsø, MD, said during his presentation at the 10th EFORT Congress. “The decrease reflects the improved quality of the prevention and treatment of diabetic foot ulcers and a general improvement in public health.”

In a previous study of patients with diabetes in the city of Trondheim, Norway, Witsø and his colleagues identified a rate of 4.4 lower extremity amputations per 1,000 patients each year between 1994 and 1997 — a rate he considered high.

Diabetic foot team lowers rate of major amputations

Incidence of major diabetic foot amputations decreased 41% in 10 years.

By Gina Brockenbrough

Norwegian investigators discovered a significant decrease in the incidence of diabetic foot amputations in one town 10 years after the establishment of a diabetic foot team at the city’s only hospital.

“We have registered a 41% decrease in major diabetic amputations,” Eivind Witsø, MD, said during his presentation at the 10th EFORT Congress. “The decrease reflects the improved quality of the prevention and treatment of diabetic foot ulcers and a general improvement in public health.”

In a previous study of patients with diabetes in the city of Trondheim, Norway, Witsø and his colleagues identified a rate of 4.4 lower extremity amputations per 1,000 patients each year between 1994 and 1997 — a rate he considered high.


Diabetic foot team

In response, the investigators established the Trondheim Diabetic Foot Team as part of the orthopaedic surgery department at St. Olav’s University Hospital. The team consisted of an orthopaedic surgeon, nurse, podiatrist, prosthetist and orthotist, and focused on preventative care and early treatment.

The investigators compared the incidence of diabetic amputations from 1994 to 1997 with information from 2004 to 2007.

Eivind Witso, MD
Eivind Witsø


The investigators found that the overall incidence of diabetic amputations per 1,000 patients with diabetes per year significantly decreased from 4.4 to 2.8 in 10 years.

Although they found that the incidence of minor diabetic amputations also decreased, the difference was not statistically significant.

Witsø said the study revealed no significant difference in the number of vascular interventions performed on patients with diabetes during the decade. He also noted that the diabetic foot team screened nearly 750 patients and performed nearly 6,000 consultations between 1996 and 2006.

A global trend?

During the paper discussion, co-moderator Per Kjaersgaard-Andersen, MD, asked Witsø if there has been a global decrease in the incidence of diabetic amputation.

“No, it’s not a global observation,” Witsø responded. He noted that while some countries have seen a decrease, diabetic foot amputation remains a major problem in other nations. He added that other researchers have observed a decline in diabetic amputations due to preventative care and an increase in vascular interventions.

“Perhaps this is one of the first studies that has shown a decrease in amputations that cannot be explained by an increase in vascular interventions,” Witsø said.

For more information:
  • Per Kjaersgaard-Andersen, MD, heads the Section for Hip and Knee Replacement, Department of Orthopaedics, Vejle Hospital, DK-7100 Vejle, Denmark; +45-7940-5716; e-mail: He has no direct financial interest in any products or companies mentioned in this article.
  • Eivind Witsø, MD, can be reached at St. Olav’s University Hospital, Norwegian University of Science, Gate 17, N-7006 Trondheim, Norway, 7030; +47-738-68000; e-mail: He has no direct financial interest in any products or companies mentioned in this article.


  • Eivind W, Arne L, Stian L. Forty percent decrease in the incidence of diabetic amputations in 10 years. Paper F197. Presented at the 10th EFORT Congress. June 3-6, 2009. Vienna.

Tuesday, September 1, 2009

Pine Bark Study Shows Further Progress Against Osteoarthritis

A new study on pine bark as an osteoarthritis treatment showed Pycnogenol reduced osteoarthritis (OA) symptoms by 56% and provided pain relief. In the study, held at Italy’s Chieti-Pescara University, 156 patients with knee OA received 100 milligrams of Pycnogenol or placebo daily for three months and were evaluated using a number of tools. Patients were permitted to continue taking their choice of pain medication provided they recorded every tablet in a diary for later evaluation. Results indicated Pycnogenol, an antioxidant plant extract from the bark of the French maritime pine tree, was an effective OA treatment and provided OA pain relief. In addition, the Pycnogenol group also:
  • • Experienced a 55% improvement in joint pain.
  • • Reduced pain medication use by 58%.
  • • Had a 63% improvement in gastrointestinal complications.
  • • Reduced stiffness by 53%.
  • • Improved physical function scores by 57%.
  • • Enhanced overall well being by 64%.
“The results of this study are significant as they clearly demonstrate the clinical action of Pycnogenol on OA and management of symptoms,” said Gianni Belcaro, a lead researcher of the study. “The use of Pycnogenol may reduce costs and side effects of anti-inflammatory agents and offer a natural alternative solution to people suffering from OA.”


The Bio-Spacers Range from Orthopaedic Innovation Limited

The Bio-Spacers range from Orthopaedic Innovation Limited, a member of the Medsmart Solutions family, are innovative and highly effective devices designed to help overcome arthroplastic infections, whilst maintaining mobility and the quality of life for the patient.

These temporary, implantable devices, which incorporate Gentamicin, are used to provide a replacement for a joint prosthesis which has been removed as a result of a septic process. They release antibiotic into the surrounding tissues to help the treatment of infected total joint replacement and facilitate successful re-implantation of the definitive prosthesis.

Our range of Bio-Spacers are made from O-I Bone Cement and the Hip Spacer is reinforced with a Stainless Steel (316L) insert to enhance strength. All our spacers feature highly polished surfaces to prevent lesions to joint surfaces and various models and sizes are available. O-I Bio-spacers’ key features are:
  • Maintenance of joint space, mobilisation and limb length (Partial weight- bearing and functional use of the limb must be assessed on an individual patient basis).
  • Effective in-situ release of high local antibiotic dosage with reduced systemic effects.
  • Homogeneous distribution of antibiotic in the cement.
  • Implantable with bone cement.
  • Improved quality of life between surgeries.
  • Eventual easier re-implantation of the definitive prosthesis.
  • Shorter hospitalisation.
  • Lower costs per treatment.
  • Improved recovery index.