ANTERIOR CRUCIATE LIGAMENT-INJURY & MANAGEMENT

ANATOMY  ACL is composed of multiple collagen

fascicles surrounded by an endotendineum which is grouped into fibers measuring around 38mm in length (range 25 to 41 mm) and 10 mm in width (range 7 to 12 mm)

  Microspocially composed of interlacing fibrils (150 to 250 Nanometer in diamter)

  synovial membrane envelope the ACL

ORIGIN - From the posteromedial corner of

medial aspect of lateral femoral condyle in the

intercondylar notch INSERTION - Fossa in front of & lateral to anterior

spine of tibia       

ACL is composed of two principal parts 1. Small Anteromedial band and 2. Larger bulky posterolateral portion

CLINICAL IMPORTANCE    - Anteromedial bundle is tight in flexion

and the posterolateral bundle is tight in extension - In extension both bundles are parallel    - In flexion both bundles are crossed

Action

These attachments allow the ACL to resist anterior translation and medial rotation of the tibia, in relation to the femur.

INNERVATION:         - Tibal nerve( Infiltrates the capsule

posteriorly)        - Golgi tendon receptorsBLOOD SUPPLY:         - Major blood supply is from MIDDLE GENICULAR ARTERY

  Bony attachments do not provide a significant source of blood to distal or proximal ligaments

ACL vascularization arises from the middle genicular artery and vessels of the infrapatella fat pad and adjacent synovium

The artery gives rise to periligamentous vessels which form a web-like network within the synovial membrane

These periligamentous vessels give rise to penetrating branches which transversely cross the ACL and anastomose with a network of longitudinally oriented endoligamentous vessels

Terminal branches of the inferior medial and lateral genicular arteries supply the distal portion of the ACL directly.

The extremities of the ACL seem to be better vascularized than the middle part, and the proximal portion seems to have a greater vascular density than the distal portion

CAUSE OF ACL INJURY

The anterior cruciate ligament can be injured in

several ways Changing direction

rapidly Stopping suddenly Slowing down while

running Landing from a jump

incorrectly Direct contact or collision,

such as a football tackle

Several studies have shown that female athletes have a higher incidence of ACL injury than male athletes because of Differences in

- Physical conditioning - Muscular strength - Neuromuscular control - pelvis and lower extremity

(leg) alignment and - the effects of estrogen on

ligament properties.

ACL injuries occur in combination with damage to

-The meniscus -Articular cartilage or -Other ligaments

Secondary damage may occur in patients who have

repeated episodes of instability due to ACL injury.

With chronic instability, up to 90 percent of patients will have meniscus damage when reassessed 10 or more years after the initial injury.

Similarly, the prevalence of articular cartilage lesions increases up to 70 percent in patients who have a 10-year-old ACL deficiency

GRADING

Partial tears of the anterior cruciate ligament are

rare

Most ACL injuries are complete or near complete tears

Injured ligaments are considered "sprains" and are graded on a severity scale.

Grade 1 Sprains.  The ligament is mildly damaged . It has been

slightly stretched, but is still able to keep the knee joint stable.

Grade 2 Sprains. The ligament is stretched to the point where it

becomes loose. This is often referred to as a partial tear of the ligament.

Grade 3 Sprains.  This type of sprain is most commonly referred to

as a complete tear of the ligament. The ligament has been split into two pieces, and the knee joint is unstable.

SYMPTOMS

When ACL is injured , pt might hear a "popping"

noise.

Other typical symptoms include: -Pain with swelling. -Loss of full range of motion -Tenderness along the joint line -Discomfort while walking

PHYSICAL EXAMINATION

INCLUDE ANTERIOR DRAWER TEST LACHMAN’S TEST PIVOT SHIFT TEST KT-2000 ARTHROMETER TEST

ANTERIOR DRAWER TEST

To perform anterior drawer test, examiner grasps pt's tibia & pulls it forward when the affected leg is flexed at 90 degree while noting degree of anterior tibial displacement

LACHMAN’S TEST

This is a variant of the anterior drawer test

The examination is carried out with the knee in 15 deg of flexion, and external rotation (relaxes IT band)

For a right knee, the examiner's right hand grips the inner aspect of the calf and the left hand grasps outer aspect of the distal thigh

Attempt to quantify the displacement in mm is done by comparing this displacement to the normal side

End point should be graded as hard or soft       - End point is said to be hard when the ACL

abruptly halts the forward motion of the tibia on

the femur        - End point is soft when there is no ACL &

restraints are more elastic secondary stabilizers;

PIVOT SHIFT TEST

 During this test, pt is kept in supine & examiner holds pt's leg with both hands

    abduct the pt’s hip (to relax the ITB and allow the tibia to rotate) Holding the heel in one hand and applying a valgus

stress in the other hand, the knee is slowly flexed   

   

The tibia, as well as the valgus, subluxes easily if anterior force is applied.

After the anterior subluxation of the tibia is noticed, the knee is slowly flexed, and the tibia will reduce with a snap at about 20° to 30°of flexion.

INVESTIGATIONS

MRI Arthroscopy

INVESTIGATION

TREATMENT

NON-SURGICAL METHOD SURGICAL METHOD

Immediately after injury R.I.C.E ( Rest Ice Compression Elevation ()

Non surgical treatment Exercise (after swelling decreases and

weight-bearing progresses) Braces

Rehabilitation Brace Functional Brace

Nonsurgical Treatment

Nonsurgical management is indicated in patients with

- partial tears and no instability symptoms - complete tears and no symptoms of

knee instability - Who do light manual work or live

sedentary lifestyles - Whose growth plates are still open

(children)

Precautions

Modification of active lifestyle to avoid high demand activities

Muscle strengthening exercises for life May require knee brace Despite above precautions ,secondary

damage to knee cartilage & meniscus leading to premature arthritis

Surgical Treatment

Timing of Surgery 1)  Swelling in the knee must go down to near-

normal levels 2)  Range-of-motion (bending and straightening) of

the injured knee must be nearly equal to the uninjured knee

3)  Good Quadriceps muscle strength must be present.

 Usually it takes a couple of weeks after injury before ACL reconstruction can be performed.

The presence of any associated injuries to the knee joint involving cartilage, meniscus, or other ligaments may change the time-frame for surgery.

Surgical Treatment

ACL tears are not usually repaired using suture to

sew it back together, because repaired ACLs have

generally been shown to fail over time

Therefore, the torn ACL is generally replaced by a

substitute graft made of tendon

The grafts commonly used to replace the ACL include

Patellar tendon Hamstring

tendon Quadriceps

tendon

patellar tendon, Achilles tendon, semitendinosus, gracilis, or

posterior tibialis tendon

autograft Allograft

Patients treated with surgical reconstruction of the

ACL have long-term success rates of 82 %- 95%

The goal of the ACL reconstruction surgery is to prevent instability and restore the function of the torn ligament, creating a stable knee.

Recurrent instability and graft failure are seen in approximately 8% of patients.

PATIENT CONSIDERATIONS

Active adult patients involved in sports or jobs that

require pivoting, turning or hard-cutting as well as

heavy manual work are encouraged to consider

surgical treatment. Activity, not age, should determine if surgical intervention should be considered.

In young children or adolescents with ACL tears,

early ACL reconstruction creates a possible risk of

growth plate injury, leading to bone growth

problems. The surgeon can delay ACL surgery until

the child is closer to skeletal maturity or the surgeon

may modify the ACL surgery technique to decrease

the risk of growth plate injury.

A patient with a torn ACL and significant functional instability has a high risk of developing secondary knee damage and should therefore consider ACL reconstruction.

It is common to see ACL injuries combined with damage to the menisci (50 %), articular cartilage (30 %), collateral ligaments (30 %), joint capsule,

or a combination of the above.

Surgical Choices

1.PATELLAR TENDON AUTOGRAFT.  The middle third of the patellar tendon of the patient, along with a bone plug from the shin and the patella is used in the patellar tendon autograft. Occasionally referred to by some surgeons as the "gold standard" for ACL reconstruction, recommended for high-demand athletes and patients whose jobs do not require a significant amount of kneeling.

In studies comparing outcomes of ACL reconstruction, the rate of graft failure was lower in the patellar tendon group

 In addition, most studies show equal or better

outcomes in terms of postoperative tests for knee

laxity (Lachman's, anterior drawer and instrumented

tests) when this graft is compared to others.

The Disadvantages of the patellar tendon autograft are:

-Postoperative patello femoral pain -Pain with kneeling -increased risk of postoperative

stiffness -risk of patella fracture

-Quadriceps Weakness -Persistent Tendon Defect

2.Hamstring tendon autograft. The semitendinosus hamstring tendon on the

inner side of the knee is used in creating the hamstring tendon autograft for ACL reconstruction. Some use an additional tendon, the gracilis,

which is attached below the knee in the same area. This creates a two- or four-strand tendon graft.

Hamstring graft proponents claim there are fewer

problems associated with harvesting of the graft

compared to the patellar tendon autograft including: - Fewer problems with anterior knee pain

after surgery - Less postoperative stiffness problems - Smaller incision - Faster recovery

The graft function may be limited by the strength and type of fixation in the bone tunnels, as the graft does not have bone plugs. 

There have been conflicting results in research studies as to whether hamstring grafts are slightly more susceptible to graft elongation (stretching), which may lead to increased laxity during objective

testing. Recently, some studies have demonstrated decreased hamstring strength in patients after surgery.

There are some indications that patients who have

intrinsic ligamentous laxity and knee hyperextension

of 10 degrees or more may have increased risk of

postoperative hamstring graft laxity on clinical exam.

Therefore, some clinicians recommend the use of

patellar tendon autografts in these hypermobile patients.

chronic or residual medial collateral ligament

laxity (grade 2 or more) at the time of ACL reconstruction may be a contra-

indication for use of the patient's own

semitendinosus and gracilis tendons as an ACL graft.

3.QUADRICEPS TENDON AUTOGRAFT.  The quadriceps tendon autograft is often

used for patients who have already failed ACL reconstruction.

Middle third of the patient's quadriceps tendon and

a bone plug from the upper end of the patella

are used.

This yields a larger graft for taller and heavier patients. Because there is a bone plug on one

side only, the fixation is not as solid as for the patellar tendon graft.

There is a high association with postoperative anterior knee pain and a low risk of patella fracture. Patients may find the incision is not cosmetically appealing

ALLOGRAFTS.

 Allografts are grafts taken from cadavers and are becoming increasingly popular. 

These grafts are also used for patients who have failed

ACL reconstruction before and in surgery to repair or

reconstruct more than one knee ligament.

Advantages of using allograft tissue include - Elimination of pain caused by obtaining the graft from the patient - Decreased surgery time and smaller incisions.

The PATELLAR TENDON ALLOGRAFT allows for strong bony fixation in the tibial and femoral bone

tunnels with screws.

However, allografts are associated with - Risk of infection, including viral

transmission (HIV and Hepatitis C)  There have also been conflicting results

in research studies as to whether allografts are slightly more susceptible to graft elongation (stretching), which may lead to increased laxity during testing.

Recently published literature may point to a higher failure rate with the use of allografts for ACL reconstruction.

Failure rates ranging from 23% to 34.4% have been reported in young, active patients returning to high-demand sporting activities after ACL reconstruction with allografts.

This is compared to autograft failure rates ranging from 5% to 10%.

Meta-analysis of Patellar vs. Hamstring tendons in ACL reconstruction

•Controlled trials with minimum 2 year follow-up•Evaluated; return to pre-injury level of activity, KT testing, Lachmanscores, pivot shift scores, ROM, complications, failures•4 studies fulfilled inclusion criteria•B-T-B showed a >20% chance return to pre-injury activity level versus hamstring, (p value = 0.01)

Yunes, M. et al “Patellar Versus Hamstring Tendons in ACL reconstruction; A Meta-analysis” Arthroscopy Vol. 17, No. 3 (March) 2001; pp248-257

Synthetic Grafts

The best scenario for the use of the synthetic graft is when the

graft can be buried in soft tissue, such as in extra-articular reconstruction.

This allows for collagen ingrowth and ensures the long-term viability of the synthetic graft.

It will be sure to fail early if it is laid into a joint bare, especially going around tunnel edges, and is unprotected by soft tissue.

Disadvantages The main disadvantage is that all the long-term

studies have shown high failure rate. There is the potential for reaction to the graft material with synovitis, as seen with the use of the Gore-Tex graft.

With the Gore-Tex graft, there was also the increased risk of late hematogenous joint infection.

The results that have been reported with the use of the Gore-Tex

graft suggest that it should not be used for ACL reconstruction.

Unacceptable failure rates have also been reported with the use of the Stryker Dacron ligament and the Leeds-Keio ligament.

` GRAFT FIXATION

Ultimate load to failure of femoral fixation devices.

Mitek 600N BioScrew 400N Endo-button: tape 500N BioScrew: Endo-pearl 700N Bone mulch screw 900N Cross pin 900N Endo-button with closed loop tape 1300N

Interference Fit Screws

Advantages Quick, familiar, and easy to use. Direct bone to tendon healing, with Sharpey’s fibers at the

tunnelaperture. Less tunnel enlargement. Disadvantages The disadvantages are as follows: Longer graft preparation time. Bone quality dependent. Damage to the graft with the screw. Divergent screw has poor fixation. Removal of metal screw makes revision difficult

Interference screw

Biodegradable

Metalic

Inteference Screw

Cross-Pin Fixation

Advantages The advantages are as follows: Strongest tested fixation. May individually tension all bundles of graft.Disadvantages The disadvantages are as follows: Pin may tilt in soft bone and lose fixation. Steep learning curve of fiddle factor. Special guides are required.

Transfix

Crosspin/transfix

Endobutton

The EB is a small oval button that anchors the graft against the outer femoral cortex.

The Endobutton (EB) is the most widely used femoral fixation device worldwide that is designed specifically for soft tissue grafts.

Pioneered by Dr. Thomas Rosenberg and introduced around 1990, it was the first device specifically designed to hold soft tissue grafts.

As originally designed, the surgeon would tie a Dacron tape connecting the button to the tendon.

In the past 5 years, this technique has been largely supplanted by use of the EB-CL (continuous loop), which obviates the need to tie knots.

Due to the longevity of the device, there is a much greater literature concerning it than any of the other newer, soft tissue–specific devices.

ENDOBUTTON

Advantages The Endo-button with closed loop tape is strong, The plastic button is cheap, available and easy

to doDisadvantages Fixation site is distant with increase in laxity,

with the bungee cord effect. Increased in tunnel widening. Plastic button has low pullout strength,

dependent on the sutures

Endobuttom Loop

Clinical Results In the largest meta-analysis of anterior

cruciate ligament reconstruction (ACLR) autografts, the EB-hamstring combination was found to have the highest stability rates of any graft-fixation construct when paired with modern tibial fixation.Morbidity has been minimal.

 Milagro (Beta-Tricalcium Phosphate, Polylactide Co-Glycolide Biocomposite)

The Milagro screw can be used for femoral or tibial fixation for soft tissue or bone–tendon–bone (BTB) autografts or allografts. It is available in various diameters from 7 to 12mm and in 23-, 30-, and 35-mm lengths. The Milagro screw is made from a polymer composite, Biocryl Rapide.

EZLoc Femoral Fixation of a Soft Tissue Graft The EZLoc (Arthrotek, Warsaw, IN) is a cortical femoral

fixation device for a soft tissue anterior cruciate ligament (ACL) reconstruction that combines superior fixation properties (high resistance to slippage, infinite stiffness, and 1427N strength) with a simple surgical technique.

The EZLoc consists of a deployable lever arm connected to an axle in a slotted body through which the ACL graft is looped.

The EZLoc comes sterilely package with a sharp-tip passing pin that is secured in the slotted body with a suture tied under tension. The passing pin is passed through the tunnels, the gold lever arm is positioned lateral, and the soft tissue graft is looped through the slot in the EZLoc.

Tibial Fixing Devices

Ultimate load to failure of tibial fixation devices. Single staple 100N Double staple 500N Screw post 600N Button 400N RCI 300N BioScrew 400N BioScrew and button 600N Intrafix 700N Screw and washer 800N Washer Loc 900N

One bundle or two bundle ACL

reconstruction

What is an “Anatomic” ACL reconstruction?  Every person is different; some people are short,

others are tall. Similarly, each person has a different size and shape of the ACL. In order to properly reconstruct the ACL it is important to reproduce each persons individual anatomy.

   The goals of anatomic ACL reconstruction are to:   Restore 60 – 80% of normal ACL anatomy  Regain stability and return to pre-injury activity level  Maintain long term knee health

What is anatomic Double-Bundle ACL reconstruction?

  In a “double-bundle” ACL reconstruction, the ACL is restored using two bundles. Just like the normal ACL, there will be an AM and a PL bundle.

In a “single-bundle” reconstruction, the ACL is restored using one bundle. There are some benefits of a “double-bundle” reconstruction, when compared to a “single-bundle” reconstruction.

 Anatomic double-bundle reconstruction better restores knee stability compared to single-bundle reconstruction.

  Because anatomic double-bundle reconstruction uses two bundles to restore the ACL, it allows for a replacement of a larger size ACL

Pre requisite for single-bundle/double-bundle reconstruction

An ACL insertion site greater than 18 mm allows for double-bundle reconstruction.

If the insertion site is less than 14 mm, there is only space available for a single-bundle procedure.

Between 14 – 18 mm, we can perform either double- or single-bundle reconstruction.

Indications for single bundle recon. The patient is still growing and his or her

growth plate is not closed. The patient has severe arthritis of the knee. The patient has multiple knee ligament

injuries or a knee dislocation and multiple other ligaments need to be reconstructed at the same time.

The patient has bone that is severely bruised. The patient has a small Intercondylar“notch”.

A prospective comparative cohort study was carried out with 72 consecutive patients with chronic ACL deficiency to compare three ACL reconstruction procedures using hamstring tendon grafts.

The first 24 patients underwent a single-bundle procedure using a six-strand hamstring tendon graft.

The next 24 patients underwent a nonanatomical double-bundle procedure using four-strand and two-strand hamstring tendon grafts.

The final 24 patients underwent the anatomical double-bundle procedure using the same four-strand and two-strand hamstring tendon grafts. All 72 patients underwent postoperative management with the same rehabilitation protocol.There were no significant differences among the background factors.

Conclusion The postoperative anterior laxity

measured was significantly less after the anatomical double-bundle reconstruction than after the single-bundle reconstruction. Concerning the results of the pivot-shift test

Outcome of Arthroscopic Single-Bundle Versus Double-Bundle Reconstruction of the Anterior Cruciate Ligament: A Preliminary 2-Year Prospective Study

Se-Jin Park, M.D., Young-Bok Jung, M.D., Hwa-Jae Jung, M.D., Ho-Joong Jung, M.D., Hun Kyu Shin, M.D., Eugene Kim, M.D., Kwang-Sup Song, M.D., Gwang-Sin Kim, M.D., Hye-Young Cheon, P.A., Seonwoo Kim, Ph.D.Received: December 29, 2008; Accepted: September 9, 2009; Published Online: February 22, 2010

ArthroscopyVolume 26, Issue 5, Pages 630–636, May 2010

 113 were included in this study. They serially obtained clinical and radiologic data preoperatively and postoperatively. They compared preoperative data and data at 2 years postoperatively in patients who had undergone single-bundle ACL reconstruction versus patients who had undergone double-bundle ACL reconstruction.

There were 50 single-bundle reconstructions and 63 double-bundle reconstructions. Anteroposterior stability was assessed objectively by anterior stress radiographs with the telos device (telos, Marburg, Germany) and the maximal manual test with the KT-2000 arthrometer

Conclusions Double-bundle reconstruction of the ACL

by a method using 2 femoral tunnel and 2 tibial tunnels showed no differences in stability results or any other clinical aspects or in terms of patient satisfaction.

COMPLICATIONS

Skeletally immature patients Anterior cruciate ligament injuries in

skeletally immature adolescents are being diagnosed with increasing frequency.

Nonoperative management of midsubstance ACL injuries in adolescent athletes frequently

results in a high incidence of giving-way episodes, recurrent meniscal tears, and early onset of osteoarthritis

The concern about ACL reconstruction in the athlete with open growth plates is that there will be

premature fusion of the plate, growth arrest, and potential for angular deformities.

Skeletally immature patients Non surgical methods

or surgical methods

Non surgical method In some less active individuals with mild-

to-moderate instability, reduction of activity level may be all that is necessary until they have had an appropriate growth spurt and maturing of the physes.

Muscle strengthening exercises knee brace Away from sports activities

TRANSEPIPHYSEAL REPLACEMENT OF ANTERIOR CRUCIATE LIGAMENT USING QUADRUPLE HAMSTRING GRAFTS

The transepiphyseal replacement of anterior cruciate ligament using quadruple hamstring grafts

procedure described by Anderson is indicated in patients in Tanner stage I, II, or III of development.

The procedure is contraindicated in patients in Tanner stage IV of development, who can have conventional anterior cruciate ligament reconstruction

The tunnels are drilled centrally through the epiphysis and fixed with a button on the periosteal surface. There are no reported growth deformities with this technique.

Anderson transepiphyseal replacement of anterior cruciate ligament using quadruple hamstring grafts

physeal-sparing, combined intraarticularand extraarticular reconstruction of acl by Kocher, Garg, and Micheli

Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients With Transphyseal Tunnels Lauren H. Redler, M.D., Rebecca T. Brafman,

B.A., Natasha Trentacosta, M.D., Christopher S. Ahmad, M.D.(Department of Orthopaedic Surgery, Columbia University Medical Center, New York, New York, U.S.A.)

Arthroscopy Volume 28, Issue 11, Pages 1710–1717, November 2012

Moises Cohen, M.D., Ph.D., Mario Ferretti, M.D., Ph.D., Marcelo Quarteiro, M.D., Frank B. Marcondes, M.D., João P.B. de Hollanda, M.D., Joicemar T. Amaro, M.D., Rene J. Abdalla, M.D., Ph.D.(Orthopedic Sports Medicine Division, Department of Orthopaedic Surgery and Traumatology, Universidade Federal de São Paulo–Escola Paulista de Medicina, São Paulo, Brazil)

Arthroscopy Volume 25, Issue 8, Pages 831–838, August 2009

Conclusions ACL reconstruction by use of the

transphyseal technique in an immature skeleton with a hamstring autograft, with careful attention being paid to the technique, resulted in good clinical outcomes and no growth abnormalities.