The document discusses the anatomy, injury mechanisms, symptoms, and treatment options for anterior cruciate ligament (ACL) injuries, emphasizing the structural composition and function of the ACL. It outlines various classification systems for ACL tears, diagnostic tests, and both non-surgical and surgical treatment approaches, including autografts and allografts, while highlighting the long-term success rates and potential complications related to each method. Additionally, it notes the importance of careful surgical timing and patient-specific considerations, particularly in younger patients.

1. Presented By: Dr Shahrukh Mohammad
Moderator : Dr Pavan Kumar
Dept of Orthopaedics MRMCW
Anterior Cruciate Ligament (ACL)
Injury And Management

2. 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)
 Microscopically composed of interlacing fibrils (150 to 250
nanometer in diameter)
 Synovial membrane envelope the ACL

3. Collagen Composition of ACL
The collagen provides its strength and elasticity
Type I Collagen: Predominant (70-80%), ensuring tensile strength.
Type III Collagen: Found in smaller quantities (10-20%),
supporting repair and flexibility.
Type V and VI Collagen: Present in trace amounts, contributing to
structural integrity.

4. Collagen Structure
Fibrils: Collagen molecules organize into fibrils, the basic ACL
building blocks.
Fibers: Aggregates of fibrils that form the ACL’s primary structural
framework.
Ligament Bundles: Organized fibers provide the ACL with
strength, stability, and flexibility.

5. Collagen Function
Mechanical Strength: Collagen enables the ACL to withstand
high tensile forces.
Elasticity: Ensures the ligament can absorb and distribute
stress efficiently.
Stability: Maintains proper joint movement by preventing
excessive translation.

6. Injury and Healing
Collagen Disruption: Injuries damage collagen, causing
ligament instability.
Healing Process: Involves collagen synthesis and remodeling to
rebuild strength and restore function.
Clinical Importance: Understanding collagen’s role aids in
developing advanced repair and regeneration techniques.

7. 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

8.  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

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

15. INNERVATION:
- Tibal nerve( Infiltrates the capsule posteriorly)
- Golgi tendon receptors
BLOOD SUPPLY:
- Major blood supply is from
MIDDLE GENICULAR ARTERY

16.  ACL vascularization arises from the middle genicular
artery and vessels of the infrapatellar 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

17.  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

18. 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

20.  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
- The effects of estrogen on
ligament properties.

21.  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.

22.  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

23. 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.

24.  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.

25. Sherman Classification ACL Tears

26. Sherman Classification
It categorizes ACL tears based on the tear's location in the proximal
half of the ligament.
Types of Tears:
Type 1: Proximal avulsion tear.
Distal remnant > 90% of total ligament length.
Type 2: Proximal tear.
Distal remnant 75-90% of total ligament length.
Type 3: Mid-substance tear.
Distal remnant 25-75% of total ligament length.
Type 4: Mid-substance tear.
Up to 50% of ligament tissue left on the femur.

27. SYMPTOMS
 When ACL is injured , patient might hear a
"popping" sound.
 Other typical symptoms include:
-Pain with swelling.
-Loss of full range of motion
-Tenderness along the joint line
-Discomfort while walking

28. PHYSICAL EXAMINATION
INCLUDE
 ANTERIOR DRAWER TEST
 LACHMAN’S TEST
 PIVOT SHIFT TEST
 KT-2000 ARTHROMETER TEST

29. ANTERIOR DRAWER TEST

30. 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

31. LACHMAN’S TEST

32. 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 the iliotibial band)

33.  For a right knee, the examiner's right hand grasps 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

34.  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 restraints
and tibia moves forward with a soft or “mushy” end
point

35. PIVOT SHIFT TEST

36. PIVOT SHIFT TEST
 During this test, pt is kept in supine & examiner
holds pt's leg with both hand 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

37.  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.

38. Instrumented Ligament Testing

39. Instrumented Ligament Testing
• Devices like KT-1000 and KT-2000 arthrometers
measure anteroposterior displacement.
• A difference of
i. <3 mm between limbs indicates normal function;
ii. ≥3 mm suggests ligament injury.

40. Imaging Studies for ACL Injury
1. Radiographic Findings:
• Initial plain radiographs rule out bony pathology or
associated injuries.
• Avulsion Fractures: Easily identified on lateral view,
including Segond fracture associated with ACL injuries.
• Degenerative Changes: Anteroposterior standing
radiographs can assess osteophyte formation and joint
space narrowing for surgical planning.

41. 2. MRI:
• MRI is crucial for diagnosing ACL injuries, with about 95%
accuracy.
• Normal ACL Appearance:Appears as a smooth, low-signal
intensity structure on sagittal images.
• Tear Indicators: Discontinuity in the ligament on sagittal
views; high-signal intensity changes on T2-weighted
sequences indicate contusions or partial tears.
• Additional Findings: Acute anterior bowing of the PCL and
"bone bruises" (areas of edema in femoral/tibial condyles)
visible on MRI.

42. INVESTIGATION

43. 3. Arthroscopy

44. TREATMENT
 NON-SURGICAL METHOD
 SURGICAL METHOD

45.  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

46. 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)

47. 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

48. Surgical Treatment
Timing of Surgery
 Swelling in the knee must go down to near-normal levels
 Range-of-motion (bending and straightening) of the
injured knee must be nearly equal to the uninjured knee
 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.

49. 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

50. 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

51.  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.

52. 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.

53.  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.

54.  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.

55. Surgical Choices
1. PATELLAR TENDON AUTOGRAFT

56.  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

57.  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.

58. 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

59. 2. Hamstring tendon autograft.

61.  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

62.  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.

63.  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.

64. NOTE:
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.

65. 3.QUADRICEPS TENDON AUTOGRAFT.

67.  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

68. ALLOGRAFTS

69.  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.

70. The PATELLAR TENDON ALLOGRAFT allows for
strong bony fixation in the tibial and femoral bone
tunnels with screws.

71.  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.

72.  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%.

73. 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.

74. 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-
Texgraft 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.

75. GRAFT FIXATION
Graft fixation is a procedure that stabilizes a graft within a bone
tunnel until it's incorporated into the bone and ensures the
ligament substituted is securely fixed.
The goal of graft fixation is to:
1. Maximize the graft's strength, stiffness, stability, and
durability
2. Minimize graft movement and elongation
3. Prevent synovial fluid from entering the bone tunnel, which
can delay graft incorporation and increase the risk of tunnel
enlargement

76. Interference screw

77.  Biodegradable
 Metalic

79. Advantages
 Quick, familiar, and easy to use.
 Direct bone to tendon healing, with Sharpey’s fibers at
the tunnel aperture.
 Less tunnel enlargement.

80. 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

81. Cross-Pin Fixation

82. 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.

83. Transfix

84. Advantages
 Strong, stable fixation
 Reduces graft slippage
 Cost-effective
Disadvantages
 Risk of femoral fracture
 Difficult for revision surgeries
 Potential tunnel widening
 May damage graft fibers

85. Endobuttom Loop

86.  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.

87. Advantages
 The Endo-button with closed loop tape is strong,
 The plastic button is cheap, available and easy to do
Disadvantages
 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

88. 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.

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

90.  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
in width and 30-35-mm lengths.
 The Milagro screw is made from a polymer
composite, Biocryl Rapide.

91. EZLoc Femoral Fixation of a
Soft Tissue Graft

92.  It is a cortical femoral fixation device for a soft tissue in
anterior cruciate ligament (ACL) reconstruction that combines
superior fixation properties (high resistance to slippage,
infinite stiffness, and 1427N strength) with a simple surgical
technique.
 It consists of a deployable lever arm connected to an axle
in a slotted body through which the ACL graft is looped.
 It 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.

93. Ultimate load to failure of femoral fixation devices.
 BioScrew 400N
 Endo-button: tape 500N
 Mitek 600N
 BioScrew: Endo-pearl 700N
 Bone mulch screw 900N
 Cross pin 900N
 Endo-button with closed loop tape 1300N
Femoral Fixing Devices

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

95. One bundle or two bundle ACL reconstruction

96.  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:
1. Restore 60 – 80% of normal ACL anatomy
2. Regain stability and return to pre-injury activity level
3. Maintain long term knee health

97. 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.
Single-Bundle ACL reconstruction
 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.

98.  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

99. 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.

100. Indications for single bundle recon.
 The patient is still growing and the 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.

103. NOTE:
In many studies, 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.

104. COMPLICATIONS

105. 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 recurrent meniscal tears and early onset
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.

106. Skeletally immature patients
 Non surgical methods
or
 Surgical methods

107. 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

108. Surgical method
 Recommended if instability persists despite conservative
treatment Muscle strengthening exercises
 Techniques:
1. Transphyseal reconstructions for patients between
puberty and growth cessation.
2. Partial transphyseal procedures can be safe but require
careful technique to avoid growth disturbances.
3. Physeal-sparing techniques to avoid damage to growth
plates.

109. TRANSEPIPHYSEAL REPLACEMENT OF ANTERIOR CRUCIATE
LIGAMENT USING QUADRUPLE HAMSTRING GRAFTS
 The transepiphyseal replacement of anterior cruciate ligament
using quadruple hamstring grafts is the procedure described by
Anderson and 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.

110. Anderson transepiphyseal replacement of anterior
cruciate ligament using quadruple hamstring grafts

111. Physeal-sparing (combined intraarticular
and extraarticular) reconstruction of ACL by Kocher, Garg, and Micheli

112. Recent advancement
JewelACL for ACL Reconstruction

113. JewelACL for ACL Reconstruction
It is a polyester permanent implant for ACL reconstruction.
Tensile Strength: Matches the semitendinosus hamstring tendon
(~1200 N).
Usage:
With or without an additional tissue graft.
Suitable for:
1. Partial Graft Sparing (PGS)
2. Total Graft Sparing (TGS) procedures.

114. 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.

115. Thank you