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Anterior cruciate ligament reconstruction

Anterior cruciate ligament reconstruction

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Anterior cruciate ligament reconstruction (ACL reconstruction) is a surgical
Surgery
Surgery is a medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, to help improve bodily function or appearance, or sometimes for some other reason...

 tissue graft
Medical grafting
In medicine, grafting is a surgical procedure to transplant tissue without a blood supply. The implanted tissue must obtain a blood supply from the new vascular bed or otherwise die.-Types of grafting:...

 replacement of the anterior cruciate ligament
Anterior cruciate ligament
The anterior cruciate ligament is one of the four major ligaments of the human knee. In the quadruped stifle , based on its anatomical position, it is referred to as the cranial cruciate ligament....

, located in the knee
Knee
The knee joint joins the thigh with the leg and consists of two articulations: one between the femur and tibia, and one between the femur and patella. It is the largest and most complicated joint in the human body. The knee is a mobile trocho-ginglymus , which permits flexion and extension as well...

, to restore its function after anterior cruciate ligament injury
Anterior cruciate ligament injury
An injury to the anterior cruciate ligament can be a debilitating musculoskeletal injury seen most often in athletes. Non-contact tears and ruptures are the most common causes of ACL injury.-Causes:...

. The torn ligament
Ligament
In anatomy, the term ligament is used to denote three different types of structures:# Fibrous tissue that connects bones to other bones. They are sometimes called "articular ligaments", "fibrous ligaments", or "true ligaments"....

 is removed from the knee before the graft is inserted through a hole created by a single hole punch. The surgery is performed arthroscopically
Arthroscopy
Arthroscopy is a minimally invasive surgical procedure in which an examination and sometimes treatment of damage of the interior of a joint is performed using an arthroscope, a type of endoscope that is inserted into the joint through a small incision...

.

Autograft vs. Allograft

  • An autograft involves the medical grafting of bone or tissue from the patient's body.
  • An allograft is the use of bone or tissue from a donor's (typically a cadaver
    Cadaver
    A cadaver is a dead human body.Cadaver may also refer to:* Cadaver tomb, tomb featuring an effigy in the form of a decomposing body* Cadaver , a video game* Cadaver , a Norwegian death metal band...

    's) body.


The patellar tendon, anterior tibialis tendon, or Achilles tendon
Achilles tendon
The Achilles tendon , also known as the calcaneal tendon or the tendo calcaneus, is a tendon of the posterior leg. It serves to attach the gastrocnemius and soleus muscles to the calcaneus bone.-Anatomy:The Achilles is the tendonous extension of three muscles in the lower leg: gastrocnemius,...

 may be harvested from a cadaver
Cadaver
A cadaver is a dead human body.Cadaver may also refer to:* Cadaver tomb, tomb featuring an effigy in the form of a decomposing body* Cadaver , a video game* Cadaver , a Norwegian death metal band...

 and used as an allograft in reconstruction. The Achilles tendon, due to its large size, must be shaved to fit within the joint cavity. There is a slight chance of rejection, which would lead to more surgery to remove the graft and replace it.

Sterilization processes exist today that make allografts a safe choice for patients. However, with allografts that are irradiated
Irradiation
Irradiation is the process by which an item is exposed to radiation. The exposure can be intentional, sometimes to serve a specific purpose, or it can be accidental...

 to remove infectious agents, there is a risk of weakening the selected tendon, although for ACL surgery the weakened tendon is generally as strong as the replaced ligament. Even with the extensive and redundant screening process for irradiated donor grafts, a risk of infection remains and it would be cause to remove the graft. Therefore, the option to use an irradiated allograft runs the largest health risk.

Patellar tendon



The patella
Patella
The patella, also known as the knee cap or kneepan, is a thick, circular-triangular bone which articulates with the femur and covers and protects the knee joint. It is the largest sesamoid bone in the human body. It is attached to the tendon of the quadriceps femoris muscle, which contracts to...

r tendon
Tendon
A tendon is a tough band of fibrous connective tissue that usually connects muscle to bone and is capable of withstanding tension. Tendons are similar to ligaments and fascia as they are all made of collagen except that ligaments join one bone to another bone, and fascia connect muscles to other...

 connects the patella (kneecap) to the tibia
Tibia
The tibia, shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates and connects the knee with the ankle bones.The tibia is named for the greek aulos flute, also known as a tibia.-In humans:...

 (shin). The graft is taken from the injured knee, but in some circumstances, such as a second operation, the other knee may be used. The middle third of the tendon is used, with bone fragments removed on each end. The graft is then threaded through holes drilled in the tibia and femur
Femur
The femur, or thigh bone, is the most proximal bone of the leg in vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs...

, and finally screwed into place.

The graft is slightly larger than a hamstring
Hamstring
In human anatomy, a hamstring is one of the three posterior thigh muscles, or to the tendons that make up the borders of the space behind the knee. In modern anatomical contexts, however, they usually refer to the posterior thigh muscles, or the tendons of the semitendinosus, the semimembranosus...

 graft, however graft size is not a determinant of outcome. The most important factor in determining the outcome is correct graft placement.

The disadvantages include:
1. Increased wound
Wound
In medicine, a wound is a type of injury in which skin is torn, cut or punctured , or where blunt force trauma causes a contusion . In pathology, it specifically refers to a sharp injury which damages the dermis of the skin.-Types of wounds:-Open:Open wounds can be classified according to the...

 pain.
2. Increased scar formation as compared to a hamstring tendon operation.
3. Risk of fracturing the patella during harvesting of the graft.
4. Increased risk of tendinitis.
5. Increased levels of pain with activities that require kneeling years after post op.

Hamstring tendon



Hamstring autografts are made with the semitendinosus tendon either alone, or accompanied by the gracilis  tendon for a stronger graft. The semitendinosus is an accessory hamstring (the primary hamstrings are left intact), and the gracilis is actually not a hamstring, but an accessory adductor (the primary adductors are left intact as well). The two tendons are commonly combined and referred to as a four strand hamstring graft, made by a long piece (about 25 cm) which is removed from each tendon. The tendon segments are folded and braided together to form a quadruple thickness strand for the replacement graft. The braided segment is threaded through the heads of tibia and femur and its ends fixated with screws on the opposite sides of the two bones.

Unlike the patellar tendon, the hamstring tendon's fixation to the bone can be affected by motion in the post-operative phase. Therefore, following surgery, a brace is often used to immobilize the knee for one to two weeks while the most critical healing takes place. Evidence suggests that the hamstring tendon graft does just as well, or nearly as well, as the patellar tendon graft in the long-term.

The main surgical wound is over the upper proximal tibia, avoiding the typical pain sensation when one kneels down. The wound is typically smaller than the patellar tendon graft and hence less pain after the operation. Patients are typically discharged from the hospital within two days after surgery.

There seems to be some controversy as to how well hamstring tendon regenerates after the harvesting. Most studies suggest that the tendon can be regenerated at least partially, while still being inferior in strength to the original tendon.

Choice of Graft


No ideal graft site for ACL reconstruction exists, they all have advantages and disadvantages. Patella tendon grafts are still considered the historical "gold standard" for knee stability by surgeons, however they suffer a slightly higher complication rate. Hamstring grafts had initial problems with fixation slippage. Modern fixation methods of hamstrings avoid graft slippage, producing outcomes that are the same in terms of knee stability with easier rehabilitation, less anterior knee pain and less joint stiffness. The main factors in knee stability are correct graft placement by the surgeon and treatment of other menisco-ligament injuries in the knee, rather than choice of graft.

Recovery


Initial physical therapy
Physical therapy
Physical therapy is a health care profession which provides services to individuals in order to develop, maintain and restore maximum movement and functional ability throughout life...

 consists of range of motion
Range of motion
Range of motion or , is the distance that a movable object may normally travel while properly attached to another object. It is also called range of travel, particularly when talking about mechanical devices and in mechanical engineering fields...

 (ROM) exercises, often with the guidance of a physical therapist. ROM exercises are used to regain the flexibility of the ligament, prevent or break down scar tissue
Scar tissue
Scar tissue can refer to:*Granulation tissue, a product of healing in major wounds*The tissue of a scar*"Scar Tissue", a Red Hot Chili Peppers song*Scar Tissue , the autobiography of Anthony Kiedis, lead singer of the Red Hot Chili Peppers...

 from forming and reduce loss of muscle
Muscle
Muscle is the contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...

 tone. ROM exercise examples include: quadriceps contractions and straight leg raises. In some cases, a continuous passive motion
Continuous passive motion
Continuous passive motion is a treatment method designed to aid in the recovery of joints immediately after trauma or surgery. CPM is carried out by a CPM device, which constantly moves the joint through a controlled range of motion, the exact range is dependent upon the joint, but in most cases...

 (CPM) device is used immediately after surgery to help with flexibility. The preferred method of preventing muscle loss is isometric exercises that put zero strain on the knee. Knee extension within two weeks is important with many rehab guidelines.

Approximately six weeks is required for the bone to attach to the graft. However, the patient can typically walk on their own and perform simple physical tasks prior to this with caution, relying on the surgical fixation of the graft until true healing (graft attachment to bone) has taken place. At this stage the first round of physical therapy can begin. This usually consists of careful exercises to regain flexibility and small amounts of strength. One of the more important benchmarks in recovery is the twelve weeks post-surgery period. After this, the patient can typically begin a more aggressive regimen of exercises involving stress on the knee, and increasing resistance. Jogging
Jogging
Jogging is a form of trotting or running at a slow or leisurely pace. The main intention is to increase fitness with less stress on the body than from faster running.-Definition:...

 may be incorporated as well.

After four months, more intense activities such as running
Running
Running is a means for an animal to move on foot. It is defined in sporting terms as a gait in which at some point all feet are off the ground at the same time. This is in contrast to walking, where one foot is always in contact with the ground, the legs are kept mostly straight and the center of...

 are possible without risk. After five months, light ball work may commence as the ligament is nearly regenerated. After six months, the reconstructed ACL is generally at full strength (ligament
Ligament
In anatomy, the term ligament is used to denote three different types of structures:# Fibrous tissue that connects bones to other bones. They are sometimes called "articular ligaments", "fibrous ligaments", or "true ligaments"....

 tissue has fully regrown), and the patient may return to activities involving cutting and twisting if a brace is worn. Recovery varies highly from case to case, and sometimes resumption of stressful activities may take a year or longer.

The reconstructed ACL has a high success rate. Studies show that cases in which the ACL retears are generally caused by a traumatic impact. Statistically, it does not appear to matter if the patient uses a brace after recovery. A sufficiently traumatic impact to retear the ACL is unlikely to be mitigated by the use of a brace.

Phase 1 (0-2 weeks)


The goals of this phase are to:
  • Eliminate swelling due to activity
  • Progress from partial weight bearing to full weight bearing exercises
  • Regain normal range of motion
  • Increase quadriceps strength
  • Increase hamstring strength


Some equipment that can be used and exercises that can be performed are:
  • Use of Cryo-cuff
- provides cold compression
  • Isometric Contraction of Quads
  • Quad Sets
- stand against wall, push extended knee against rolled towel
- progress to straight leg raised to 30deg.
  • Wall Slides
- To increase knee flexion
  • Assisted Knee Flexion
  • Towel Squeeze
- Sit in chair, squeeze rolled towel between knees for 5 seconds. Relax & repeat.
  • VMO Strengthening Exercise
  • Supported Bilateral Calf-Raises

Phase 2 (2-12 weeks)


The goals of this phase are to:
  • Regain full knee extension
  • Restore knee flexion to +130°
  • Perform a full squat properly
  • Regain good balance and control
  • Reestablish proper gait
  • walk with cruches


Some exercises that can be performed are:
  • Mini squats
- Progress to full squats → single-leg half squat
  • Mini Lunges
- Progress to full lunges
  • Leg Press
- Double-leg → single
  • Step-ups
- lateral & forward
  • Bridges
- Double-leg → single
- Floor → Swiss ball
  • Hip Abduction w/ Theraband
  • Hip Extension w/ Theraband
  • Wobble board
- Assisted → un-assisted → eyes closed (assisted → unassisted)
  • Stork Stand
- Assisted → un-assisted → eyes closed (assisted → unassisted) → unstable surface
  • Static Proprioceptive hold/ball throwing
  • Functional Exercises that can be performed at this time include:
- Walking
- Bike
- Roman Chair

Phase 3 (3-6 months)


The goals of this phase are to:
  • Regain full range of motion
  • Regain full strength and power
  • Increase agility
allows for adaption to direction change, acceleration and deceleration
  • Be able to perform restricted sports-specific drills
  • Begin plyometric drills


Some exercises that can be performed are:
  • Continue exercises from Phase 2, progress as necessary
  • Jump & Land drills
- Jump from block & stick landing
- Double-leg landing → single-leg
  • Plyometric Drills
- Jumping over blocks, sideways & forward
- Hopping up & down steps/stairs

Phase 4 (6-12 months)


The goal of this phase is a return to activity, however it requires an ability to perform some functional performance tests such as:
  • Agility Tests
  • Illinois Agility Test
    Illinois agility test
    The Illinois agility test is a fitness test designed to test one's sport agility. It is a simple test which is easy to administer and requires little equipment. It tests the ability to turn in different directions and at different angles....

  • Zig Zag Agility Test
These tests are used to test the ability of the knee to withstand cutting and planting maneuvers
  • Standing Vertical Jump
Here you jump straight in the air from a standing start and land on two feet as stable as possible.
  • Heiden Hop Test
Here you essentially jump as far as possible with the uninjured leg and land on the injured leg. Your ability to stick the landing is indicative of good knee function.
  • Isokinetic Testing
This is used to evaluate muscle strength.
The individual should have at least 90% quadricep strength of the uninjured leg
They should also have equal hamstring strength to their uninjured leg as well

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