FAQ Category: Ankle

You may be talking about a new technique called distraction arthroplasty for ankle arthritis. It is a step in the direction of preserving joint motion, especially in young patients.

Distraction arthroplasty is done by using an external frame with rods that stretch the ankle apart. The frame looks like a circular cage around the ankle and lower leg. A thin wire is placed through the joint and acts as a guide wire until the device is fully in place. Then the wire is removed.

The patient ends up with a cage that has two rings (one at the top, one at the bottom) and two rods in between the top and bottom rings. The rods are lengthened a little bit at a time pulling the joint apart. The joint only separates a tiny amount (up to three millimeters which is about one tenth of an inch).

The separation combined with increased pressure from walking stimulate the joint cartilage to produce new, healthy chondrocytes (cartilage cells). As for the question: who can benefit from this procedure? There aren’t a lot of published studies to help answer this question. What is known so far is based on small studies with only 20 to 24 patients.

Right now, it looks like younger patients who still have a fairly mobile ankle joint are better candidates than older adults with a stiff joint. Patients must be motivated to follow the surgeon’s directions following the procedure. Keeping active despite any persistent pain or discomfort is an important part of the post-operative plan. Rehab under the direction of a physical therapist is an important part of the recovery process.

The only way to know for sure what’s best for you is to see your surgeon for an examination and evaluation. There may be some simpler management tools that could help you. This particular procedure can only be done on an ankle with good alignment without deformities.

Surgery can be done to get the joint ready for the distraction arthroplasty technique so it’s not a quick and easy fix. The advantage is that joint motion is preserved (saved) until such time as more permanent approaches are required (e.g., fusion) that might sacrifice motion.

For anyone with painful and limiting joint arthritis, ankle arthritis can be very disabling. When every step is torture, activities become severely limited and quality of life goes downhill fast.

If surgery is not an option because of personal choice, ongoing conservative (nonoperative) care is important. Good nutrition, pain relieving medications, physical therapy, and even exercise become important factors in maintaining health and function. Don’t neglect these daily tools in self-care while you are waiting.

In the meantime, there is one new surgical procedure that might be of interest to you. It’s called distraction arthroplasty. The surgeon uses a device called a distraction frame to take hold of both sides of the joint and literally stretch them apart. It seems that by doing so while still allowing (and even encouraging) the patient to keep walking on the foot, new cartilage cells are stimulated to grow.

There’s a fair bit of surgery that must be done before the frame can be applied. The joint is cleaned out and any deformities or misalignments in the joint are corrected before the frame is applied.

It’s not a miracle cure and the effects often aren’t felt for six months’ time. But a large percentage of patients treated with this approach are pleased with the results. They report reduced pain and improved function.

Not many people have heard of Maisonneuve injuries. The name comes from the French surgeon who first described this problem. Basically, the term refers a spiral fracture of the upper one-third of the fibula. The fibula is one of two bones in the lower leg. It is the smaller bone situated on the outside or lateral side of the leg.

People of all ages can experience a Maisonneuve injury as a result of slipping on ice, tripping and falling, falling from a height, car accidents, or sporting events. But there’s more to the injury than just the fracture.

The force of the injury pushes the ankle into a flat-footed position with intense stretch pressure along the inside of the foot and ankle. The lower leg is externally (outwardly) rotated with the foot planted on the ground.

Associated injuries can also include fractures of the malleolus (bump on either side of the ankle that we usually point to and call our ankle bone) and tears or ruptures of the surrounding ankle ligaments or joint capsule.

In severe Maisonneuve injuries, the connective tissue between the two bones (tibia and fibula) is completely torn. This is called a syndesmotic disruption. Without this strong fibrous interconnecting ligament, one bone can shift up or down in relation to the other causing a difference in leg length from one leg to the other.

The goal of treatment for these injuries is to restore normal ankle alignment and movement. Surgery may not be needed for less severe Maisonneuve ankle injuries. The patient is placed in a cast for six weeks.

This approach is acceptable when there are no soft tissue injuries of ligaments, syndesmosis, or joint capsule. For more severe Maisonneuve injuries involving the syndesmosis or other soft tissues, reconstructive surgery may be required.

When there’s enough force on the ankle to push it into external rotation while the foot is planted, a spiral-shaped fracture can occur in the upper third of the fibula. The fibula is one of two bones in the lower leg. It is the smaller bone situated on the outside or lateral side of the leg.

Essentially the lower leg is externally (outwardly) rotated with the foot planted on the ground. With a traumatic injury from a fall or sports collision, the connective tissue between the two bones (tibia and fibula) can be completely torn.

This is called a syndesmotic disruption. Without this strong fibrous interconnecting ligament, one bone can shift up or down in relation to the other. The shift can cause a difference in leg length from one leg to the other. That’s why the surgeon puts two long screws between the tibia and the fibula at the top and bottom — to hold them in good alignment while the fracture heals.

The screws can be left in place or taken out according to the surgeon’s preferences and the patient’s wishes. Many surgeons prefer to leave them in unless they have come loose and/or are backing out. Performing a second surgery to remove the hardware increases the risk of infection, fracture, poor wound healing, or other surgical complications.

There is no harm in leaving the screws in place. Unless they are bothering you, causing pain, or have been disrupted, it is considered best to leave them alone. Surgeons will take hardware out for patients who are concerned about potential harmful effects from leaving the screws in place.

Studies show that up to one-third of all patients who have ankle reconstructive surgery for ankle sprains that don’t respond to conservative care end up with continued pain. The ankle may even appear to be stable but like you, the patient feels there’s still something else wrong.

It is very possible that there are other intraarticular (inside the joint) problems. It could be there’s another ligament damaged that was missed on the first exam. Or there may be an osteochondral lesion. That refers to a piece of cartilage that has pulled away from the joint surface with a tiny piece of bone still attached.

It may be time to head back to your surgeon for a follow-up exam. An X-ray or other imaging study might show what’s going on. Otherwise, a second look with the arthroscope from all angles may be required. In some patients, the true problem isn’t revealed until an open incision is made and the surgeon can investigate all aspects of the joint and surrounding soft tissue structures.

The typical ankle sprain involves a partially or fully torn ligament along the inside (medial) or outside (lateral ankle. With severe sprains, there can also be something called osteochondral lesion of the talus (OLT). The talus is a bone that sits just above the calcaneus (heel bone).

The term osteochondral tell us that the joint cartilage (chondral) and bone (oste) just underneath the cartilage have been damaged. With some of the more severe osteochondral lesions (OCLs), there is a piece of cartilage with the bone attached that is loose in the joint causing further problems. Anytime there’s a problem inside the joint, it’s referred to as an intraarticular lesion.

The problem with a severe ankle sprain that leads to osteochondral lesion and joint instability is that these are two separate problems requiring different surgical techniques and different rehab approaches. They aren’t usually both treated at the same time. Surgery is done in two phases, which is why it’s called a staged procedure.

In the first operation (stage) the surgeon uses an arthroscope to look inside the joint and find any damage to the joint. Osteochondral lesions are removed and the joint surface is smoothed down. Rehab begins right away with weight-bearing allowed to help smooth the joint surface and stimulate healing.

Once osteochondral lesion is taken care of, the surgeon repairs any damage done to the ligaments. If the tissue is too damaged to repair, then a piece of tendon from another muscle can be used as a graft to replace the torn ligament. After a ligament repair or reconstructive surgery the patients are in a cast to protect the healing tissue. Unlike rehab for the osteochondral lesion that responds better with immediate weight-bearing, healing ligaments or grafts require uninterrupted quiet without movement.

The cast is kept on for four to six weeks and then a removable walker boot or splint is worn for a bit longer. At this point, the physical therapist can start gentle range-of-motion exercises with you. You will gradually put allowed to put full weight on that ankle. Pool therapy may be used before beginning land exercises and especially before beginning high-impact athletic activities.

Some surgeons are experimenting with ways to do both procedures during the same operation. A combination of short-term casting followed by splinting and rehab is being investigated. The idea is to find a happy medium between stimulation for the cartilage repair and stability for the ligamentous repair or reconstruction. Until this has been researched fully, most orthopedic surgeons will continue making this a two-part or staged procedure.

A sprained ankle happens when the ligaments, fibers that hold the ankle stable, get stretched and torn because the ankle is moved forcefully in an unnatural position. This could be from stepping off a sidewalk and landing on the side of your foot instead of the bottom, tripping, or landing on your foot the wrong way after a jump. Regardless of the cause, the result is pain and swelling that can range from mild to severe.

Seeing a doctor is always a good idea because an x-ray will confirm that it truly is a sprain and not a break. An untreated broken ankle could end up causing problems later down the road.

If the sprain is mild, or minimal, you may be told that it’s ok to walk on it as long as you’re careful. You may also be given some exercises to help strengthen the ankle. If the injury is moderate to severe, you likely will have your ankle splinted or braced and a follow-up with physiotherapy. Severe sprains must be watched because they could have problems with healing, which may make surgery necessary later on.

A sprained ankle, although not taken as seriously as a broken ankle by many, can be a serious injury and should be treated properly to prevent further injury or pain to the patient.

The most common cause of a sprain is “rolling” on the ankle. This means you’ve turned the foot in or out much more than it should be and this pulls on the ligaments, the fibrous tissue that holds everything together. If you pull too hard on the ligaments, you stretch them and they can tear.

Minor sprains don’t usually cause a lot of damage, but if it is a severe sprain, where the ligaments are torn through, the ankle can become unstable because there is nothing to hold it up properly. This could result in ankle damage, particularly if you roll your ankle again.

Chronic ankle pain and instability (ankle gives way underneath you when standing or walking) are the most common reasons for corrective surgery when an old injury leads to arthritis. Swelling, loss of motion, and loss of function can really disturb a person’ quality of life until surgery seems like a great idea.

Arthrodesis is a medical term that means fusion. Fusion stops motion and thereby reduces stress on the painful joint. In the case of the ankle, in order to fuse the joint and stop motion, several bones must be fused together. The effect is to off-load the ankle joint but force is then transferred to the midfoot and hindfoot. Those areas can take quite a beating over time and develop degenerative problems of their own.

Starting out with an ankle fusion is often advised before taking the bones out and replacing them with an implant (ankle joint replacement). The fused site can always be converted to a replacement later. Joint replacements are not usually done if there are serious alignment issues in the hindfoot. If the foot doesn’t line up properly, the implant will just wear unevenly and possibly fail.

Before doing a joint replacement, ankle alignment may have to be corrected. This may require soft-tissue releases, ligament reconstruction, and/or bone cuts called osteotomy. For an osteotomy, the surgeon uses a wedge of bone to correct the alignment problem (deformity) first before putting the implant in place.

You may need to make another appointment with your surgeon to discuss these choices a bit more. It’s likely that the recommendation came as enough of a surprise that you may not have heard all of the explanation the surgeon gave about your situation. Having a second conversation about the indications, benefits, pros, and cons of each approach for you specifically would be a good idea.

It sounds like your daughter may have an osteochondral lesion (OCL) of the ankle. The term osteochondral tells us that the joint cartilage (chondral) and bone (oste) underneath have been damaged.

Mild lesions cause a fissure or crack in the cartilage. With some of the more severe osteochondral lesions (OCLs), there is a piece of cartilage with the bone still attached. That fragment can become loose in the joint causing further problems.

Ankle sprains are the most common cause of osteochondral lesions. Sports athletes are affected most often. But anyone who injures the ankle or develops bone chips or fragments for any reason can develop debilitating osteochondral lesions.

Most people who are diagnosed with osteochondral lesions report ankle pain, swelling, stiffness, and weakness. There is often a history of repeated jumping, prolonged running, or other high impact activities. Many of the athletes describe frequent episodes of the ankle giving out from underneath them. This is a sign of ankle instability.

Children with mild-to-moderate osteochondral lesions seem to be able to heal spontaneously when given time and a little protection to the joint. An ankle brace, splint, or sometimes cast is used to keep the area quiet and free of movement that can create continued microtrauma to the defect. Antiinflammatory medications may be used as well. Adults are more likely to need surgery to pin the fragment in place until healing can occur. Other, more extensive procedures may be needed when the fragment has become displaced and a gaping hole is left in the joint.

Children and teens are encouraged to follow their surgeon’s advice very carefully in order to get the best results possible. Compliance with protected weight-bearing is especially important to give the area a chance to heal. This particular area of the anatomy (cartilage) doesn’t have a very good blood supply, so healing with new tissue needs all the help it can get.

As you probably saw in the PBS (public broadcast service) television special, robot-assisted surgery is still performed by the surgeon. It’s the surgeon who is guiding the robot’s mechanical arms, so this becomes another technological tool used by highly trained professionals.

Computers are also aiding surgeon in navigating difficult to reach (or see) areas. For example, osteochondral lesions (cartilage and bone pulled away from the joint surface) in the ankle can be extremely difficult to reach. There are many bones in the ankle joint of various sizes and shapes all fit together to create a very mobile joint.

Accessing osteochondral lesions between and under bones can be a real challenge — even with arthroscopic tools that allow the surgeon to see inside the joint. That’s where today’s modern technology like robots and computers makes it possible to reach the intended site reliably and accurately. Surgeries of this type can be done with minimally invasive techniques, which means a smaller incision and less disruption of the soft tissue structures in the area.

It’s expected that the end result will be a more satisfied customer (patient) so-to-speak. With improved technique the patient may experience a faster reduction in pain and faster, smoother transition back into daily and sports activities.

But don’t worry. These sophisticated, user-friendly techniques are still in the investigation mode for many procedures. Their use in everyday, ordinary hospitals and clinics is nowhere near ready to replace the orthopedic surgeon’s expertise or experience, only enhance it.

It sounds like your father may have a residual effect from the stroke called ankle clonus. Clonus is described in the medical literature as a series of involuntary muscular contractions. It is caused by a sudden stretching of the muscle. Clonus is a sign of certain neurological conditions like stroke or multiple sclerosis.

It doesn’t go away unless and until the brain recovers from the injury. In the case of a stroke causing the clonus, there’s been bleeding into the brain resulting in a cerebrovascular accident (CVA), the medical term for stroke. There are different ways to treat this problem of increased muscle tone, spasticity, and ankle clonus. Sometimes medications (antispastic drugs) can help reduce the muscle reactivity. Surgery to control muscle tone has been tried but isn’t always successful. Surgery can (and often does) cause additional problems, so other approaches are tried first.

Physical therapy is a common way to guide a patient through the rehabilitative and recovery phase after a stroke. The therapist can test for problems like increased muscle tone that is impairing daily function and help the patient and family find ways to restore as normal of function as possible. It’s likely your father had some physical therapy when he was first diagnosed — maybe while in the hospital when the stroke first happened.

But once the patient leaves the hospital setting, physical therapy may be discontinued. That doesn’t mean further rehab services are of no help now. Quite the contrary. Studies show the brain and nervous system are very plastic (changeable and responsive) even in adults.

Check with the therapist who initially evaluated and treated your father. Find out what kind of services he qualifies for. Some services are covered by insurance. There may be limits on the number of therapy sessions patients can receive depending on whether they have Medicare and/or secondary insurance. Payment out-of-pocket for services that aren’t covered may be possible.

It sounds like you are describing a dynamometer. This handheld tool is a device used to measure muscle force. Many patients suffer from hypertonia after a stroke. This means the muscles are hyperactive. A group of muscles commonly affected include the gastrocnemius (large calf muscle) and the soleus muscle (a smaller muscle that forms part of the calf).

The dynamometer helps evaluate speed and excitability of the ankle plantar flexor muscles. Plantar flexion is the movement of the foot away from the face (pointing the toes). The therapists may be measuring the quality of the plantar flexor muscle reaction when the (ankle) joint is moved. This particular measurement is important to track before and after results of treatment and to assess the patient’s overall recovery from a stroke.

Here’s some information that might help explain what’s going on. If you’ve ever held an older infant, you know when placed in an upright position, they tend to bounce on their feet. That’s a reflex. Pressure on the balls of the feet causes the ankles to plantar flex (toes point down). Eventually, the nervous system matures a bit more and this reflex is no longer so dominant. Now the child can put the foot down on the ground and walk without the plantar reflex causing bouncing.

This reflex seems to come back in adults who have had a cerebrovascular accident (CVA) (stroke). Damage to the brain from the stroke results in muscle hypertonicity (increased muscle tone). The increased tone and abnormal reflex reactions make walking normally difficult.

Physical therapists are often key members of the rehab team helping people with strokes to recover movement and function. Finding ways to reduce the excess tone and keep from triggering the plantar flexor reflex is an important part of the program. And in order to know if the treatment is working, it’s necessary to measure the muscle tone and reflex response from before to after intervention.

This is a likely explanation for what’s going on. But feel free to ask the therapist to explain what he or she is doing and why. The information may help you understand what has happened to your grandmother and may even help her understand her own condition. Patient (and family) education is a key ingredient to a successful rehab experience!

You may have an injury of the transverse tarsal joint. Sometimes this area is referred to as the Chopart joint. It’s where the talus bone meets the navicular bone and the calcaneus (heel) bone meets the cuboid bone. Since the talus sits right on top of the calcaneus, these bones and joints all work together to create a stable but mobile joint.

Injury of any of the bones or ligaments holding the bones together in the Chopart joint can affect this transitional zone where the foot meets the ankle. In fact, the most common mechanism of injury for a transverse tarsal joint injury is to have the foot pushed against the brake pedal of a car or against the foot pedal of a motorcycle as you described.

X-rays don’t always show injuries to this area because its the ligaments that are damaged. When ligaments are torn or ruptured, the joints become unstable. The bones might shift. If the joints reduce (shift back in place) during the X-ray, then it looks normal when developed.

It takes careful attention to the mechanism of injury, clinical presentation, and some additional testing to identify injuries of this type. It might be a good idea to see an orthopedic surgeon if you haven’t already — or to head back to the orthopedic specialist for a follow-up exam.

Ankle injuries can be very challenging. Anatomy of the foot and ankle structures is complex and can fool even the most experienced clinician. Most experts agree that when a patient says something isn’t quite right, a second look is warranted. Make an appointment as soon as possible. Let them know at the appointment desk that this isn’t a routine follow-up visit so that you can get in sooner than later.

An early and accurate diagnosis is essential in preventing further complications. The goal is to restore full, normal ankle motion and leg function. Additional imaging studies may be needed. Plain, two-dimensional X-rays aren’t always able to show subtle injuries to the bones and joints.

Sometimes weight-bearing or stress X-rays are needed to show instability or collapse of the bones where damage has occurred but isn’t seen on a nonweight-bearing film. CT scans may be needed from a variety of angles to see soft tissue structures in the transitional zones. This zone is the area where the foot meets the ankle.

Anytime symptoms last beyond the expected time for healing or symptoms are out of proportion to the injury, further evaluation is required. MRIs and bone scans may be needed to confirm the possibility of a stress fracture. Treatment may be changed once the final diagnosis has been made. This depends on what the physician finds on re-examination.

Ankle sprains are common among athletes like basketball players who plant the foot on the floor and pivot, shift, or make sudden directional changes. Once the joint is damaged, the risk of a second sprain or injury to some other vital part of the ankle increases dramatically. Finding a way to test for ankle stability and predicting safety in a return-to-sports decision can be difficult.

There are some ways to evaluate function, as well as identify joint instability and performance deficits. The first is the athlete’s report of the ankle giving way. This is a subjective symptom of functional ankle instability. And it’s a reliable tool to suggest further rehab is needed.

Then there’s a series of hopping tests that can add more information. These require muscle strength and stress the outside edge of the ankle (where the original injury occurred). The four tests include: 1) figure-of-8 hop, 2) side hop, 3) 6-meter crossover hop, and 4) square hop. The figure-of-8 test involves hopping on one foot in a figure-8 pattern around two cones set five meters apart (about 15 feet). The pattern is repeated two times as fast as possible.

The side-hop test requires you to hop on one foot sideways 30 centimeters (eight inches) and back 10 times (also as fast as possible). The six-meter crossover hop test requires the athlete to hop over a four-inch wide line from the right side to the left side and back along a path that was eight feet long.

And finally, in the square hop test, a 10-inch by 10-inch square of tape is placed on the floor. The person being tested has to hop in and out of the square all the way around. The tests are repeated three times and each trial is timed.

The athlete who can complete these tests without pain and without a giving-way sensation is more likely to be ready to take to the floor than someone who is slow, unable to complete the tests, and who experiences ankle stability during the testing.

If your team has an athletic trainer or physical therapist, ask him or her to work with you on a trial basis to see how strong and agile you are using the involved leg. Have your team staff put you through your paces and testing before putting your at-risk ankle back in the fray. A little front-end investment of time and caution are always advised.

The mechanics and biomechanics of ankle sprains are not fully understood. Studies using force plates and 3-D high-speed motion cameras have provided many new insights. But these are still under investigation.

What we do know is that the position of the foot and ankle just before making contact with the floor or ground and at the point of impact is extremely important. If the rear foot is in a position of inversion (slightly turned inward), there is an increased risk of spraining the lateral (talofibular) ligament.

If ankle inversion is also accompanied by a position of plantar flexion (toes pointed), the risk of ankle injury goes up as well. As your foot lands and makes contact with the floor or ground, the inverted position of the rear foot strains the lateral (talofibular) ligament of the ankle. Stepping on to an uneven surface or landing with more force than the foot and ankle were prepared for can cause hyperinversion (increased inversion) and ankle sprain. Likewise, any unexpected contact with the ground or floor can have a similar reaction.

Once the soft tissues of the ankle joint have been injured, tiny receptors within the joint can also be damaged. These receptors signal to the brain the precise location of the joint in order to prepare the ankle for the next movement. But many times, the lack of signalling feedback results in yet another injury. That’s why rehab is so important to regain normal motion and strength and to restore the signaling features of this very sensitive joint.

There isn’t as much evidence to support the use of taping as a prophylactic (preventive) measure for first-time ankle sprains as there is for reducing the number of second (or third) recurrent fractures.

A recent study done by a group of physical therapists in a biomechanics laboratory at the School of Physiotherapy and Performance Society in Dublin, Ireland investigated the use of taping to prevent injuries during jumping/landing activities.

The subjects in the study were young men and women with a history of chronic ankle instability but who had never had rehab or surgery for the problem. After learning how to do a drop landing (jumping down from a platform onto a force plate), each subject was tested in three ways.

First, they jumped down on to the unstable foot/ankle without any supportive tape. They each did three jumps. Then they repeated the same three jumps with tape around the ankle. The next step was to complete 10 repetitions each of hopping, ladder, and cutting drills before being tested again. These particular exercises are typical of the type used in sports training. This final drop landing test was done with the tape still supporting the ankle, but this time the test was performed after exercising for almost a half hour (25-minutes).

Once the testing was done and the data was all collected, analysis showed that the taping did, indeed, hold the ankle better than without taping. And the tape was still effective after exercise. Results weren’t any different or better between jumps made before and after exercise with tape. So long as the tape was on the ankle, the position of the foot and ankle remained the same.

For sure, there was more ankle plantar flexion and rear foot inversion when there was no tape used to support and hold a neutral ankle/foot position. Whether or not that prevents first-time injuries wasn’t the focus of this study as everyone in the study had already experienced their first ankle sprain. More studies are needed in this area.

It may very well be worth the time and money to tape players who have had at least one previous ankle sprain. Taping doesn’t replace the need to rehab the ankle and restore normal proprioception (sense of joint position) or kinesthesia (awareness of movement), which are both essential to normal, healthy ankle motion needed to avoid injuries.

This is definitely a question for your surgeon. Given the circumstances, if there is any way around it, the surgeon will no doubt try to find a creative solution to the problem. Some of this decision depends on the type of fracture, especially severity. If the fractured ends of the bone have separated, casting is important to avoid further displacing the bones and ending up with a significant difference in leg length from one side to the other.

Your child’s weight also helps determine what can be done. If she weighs less than 90 to 100 pounds, it may be possible to place a long pin called an intramedullary nail down the shaft (center) of the bone. This is one form of fixation used to hold the bone together while it heals. The location of the fracture is also a factor. This technique isn’t always possible if the break is at the top or bottom of the femur (rather than in the middle).

Femoral fractures in children is an area where the research is lacking. More and better research is needed in this area. Although there has been a trend toward surgical care instead of traction and prolonged casting, high-quality studies comparing the two approaches have not been done.

Surgeons know a lot more about cartilage, its properties, and its injuries now that there are MRIs and arthroscopic examinations available. These diagnostic techniques make it possible to see the exact size, shape, and location of cartilage lesions. All of these tools are used to plan the most appropriate treatment.

Nonoperative (conservative) care might work okay for sedentary (inactive) adults with a small lesion. But active individuals and especially athletes eager to get back into action will need surgery to repair or restore the cartilage. Repair débridement is the first line of treatment for small lesions (less than 1 cm2 in size). The surgeon carefully removes any loose pieces and smoothes any frayed edges.

If that doesn’t work, then the débridement may be repeated. If further treatment is needed, restoration rather than repair is advised. Restoration means that normal hyaline cartilage is harvested from a donor site and transplanted to the defect or hole in the cartilage. Sometimes the donor material comes from the patient. That’s called an autograft. When the harvested healthy cartilage comes from another person, it’s referred to as an allograft.

In either case, essentially what happens is the surgeon takes a plug of cartilage and the bone underneath it from a healthy site (usually the nonweight-bearing portion of the knee) and transplants it into the defect or hole in the damaged cartilage. This is called an osteochondral autograft transplantation (OAT).

The patient stays off that leg for several weeks after surgery to avoid disrupting the healing process. Reports so far of short- to mid-term results are very favorable with this technique. The studies are small but the majority of patients report good-to-excellent results. They say they would have the same procedure done again if they had it to do all over.

That was the first method used to try and restore the cartilage. Now, the technique has advanced forward. A new method called autologous chondrocyte implantation (ACI) is available. Healthy cartilage cells are taken from the patient and grown in a lab until 200 to 300 cells becomes 12 million cells. It takes about six to eight weeks to accomplish the multiplication process.

Then the new cartilage cells are transferred back into the defect (hole). The advantage of this approach is that the new cells can be saved in a cold place for more than a year. The disadvantage is that the procedure requires two separate operations.

In the second operation, the lesion is smoothed and prepped for the new cells. A special patch of bone is layer over the top to protect the healing area. The patch is sealed with a special fibrin cement or glue. The new cartilage cells are injected under the patch. Again, small studies are reporting good-to-excellent results that last beyond 48 months (four years).

In a few patients, the surgeons are able to do a repeat arthroscopy exam and sample some of the healed tissue to see what’s really going on. They have been able to see that the defect doesn’t always fill in with good hyaline cartilage. Sometimes it’s just a fibrous filler, so there’s some concern about that.

One final restorative technique under investigation is the matrix-induced autologous chondrocyte implantation (MACI) that you mentioned. This is similar to the autologous chondrocyte implantation. But instead of growing the harvested cells in a culture and then injecting them into the defect, they are placed on a special membrane where they grow and multiply. The membrane is then used to fill and cover the defect. No extra bone patch or flap is needed. Cells can also be harvested right next to the damaged area, rather than finding another spot to gather them (e.g., from the knee).

There are numerous possible advantages of the MACI procedure over the others: