2/5/2020
At Least It’s Not Your ACL
T. Kevin O’Malley, M.D. MD West One February 18, 2020
Objectives
• Review anatomy of the knee • Identify tendon injuries around the knee • Discuss management of patella fracture and dislocation • Review post-op management of the injured knee
Types of Knee Injuries
• Ligament Injuries • ACL, PCL, MCL and LCL • Bony Injuries • Cartilage injuries • Meniscus and Articular Cartilage • Tendon Injuries • Quad tendon and Patellar tendon
1 2/5/2020
2 2/5/2020
Patella Fractures
Mechanism of Injury • 1% of all fractures • Usually the result of a direct blow or fall • Most are transverse fractures • Men twice as likely as women • Most require surgery
Diagnosis of Patella Fracture
• Anterior knee pain • Swelling • Inability to straight leg lift • Defect in the patella • X-ray confirmation
3 2/5/2020
Treatment Options
Non surgical • Cast • Brace • Crutches
Surgical • ORIF with screws • Tension Band • Partial patellectomy • Total patellectomy
4 2/5/2020
Post-op Management • Admit for pain control • WBAT with crutches • Knee brace • Ice for comfort • Shower 3 days • Stitches out 10-14 days
5 2/5/2020
Rehabilitation • Based on injury and repair performed • Straight leg raise at 1 week • Passive ROM at 3 weeks • Resistive exercises at 6 weeks • Brace for support for 3 months • Partial patellectomy held for 4 weeks to allow soft tissue healing
Patella Instability
6 2/5/2020
PATELLA INSTABILITY
• Generic Term A) Patella dislocation B) Patella subluxation • Affects between 7-49/100,00 • 11% of musculoskeletal symptoms seen in office • 16 – 25% of all injuries in running • Higher incidence in females
7 2/5/2020
ANATOMY
A) BONY
• Patella
• Femur (Trochlea)
B) SOFT TISSUE
1. Medial Retinaculum
2. Quads (VMO)
3. MPFL
STABILITY IN MOTION
EARLY FLEXION
• Distal patellar engages superior aspect trochlear groove • Quads are dynamic stabilizer • MPFL 1° static soft tissue restraint • ˃ 50% of medial restraint forces in cadaver study • ↑Flexion contact area of patella moves proximally
MID FLEXION 90° • Proximal pole contacts distal aspect trochlear groove • Deeply engaged in groove • ↑ Flexion causes contact with MFC/ medial facet patella and LFC with lateral facet
PAST 90° FLEXION • Smaller third facet engages MFC
8 2/5/2020
THE STAR OF OUR SHOW
MPFL
MPFL
• Inserts sup/medial border of patella 6 mm below superior pole • Origin - entire length of medial femoral epicondyle • Average length 5 and 6 cm • Insertion broader than origin • Also sends branches to VMO / Medial retinaculum
9 2/5/2020
Classification of Patellar Instability • Congenital • Traumatic • Developmental
ETIOLOGY
• Multifactorial Can be traumatic from direct blow • Developmental as a result of patella alta and dysplasia • Delayed engagement in shallow trochlea • Tibial tubercle placement
HISTORY
• Anterior knee pain • Giving way, going out • Determine if specific event • What previous treatment? Successful?
10 2/5/2020
EXAM:
Inspect • Bruising • Swelling
Palpate • Medial facet • Lateral femoral condyle
• Thorough leg exam
MCL ٭ (Mimic ACL (history ٭
• Moving Patella Apprehension Test
MOVING PATELLAR APPREHENSION TEST
Knee 20 – 30° flexion • Lateral pressure on patella • ↑ bend, may ↑ apprehension = positive test • Repeat with medial direction pressure better = positive test
Q ANGLE
• Angle between ASIS and Patellar Tendon
• Males 8 - 10°
• Females 15 - 20°
11 2/5/2020
Factors that ↑ Q Angle
• External tibial torsion
• Laterally positioned TT
• Genu valgum
• ↑ Femoral anteversion
PATELLAR TILT TEST
• Patient supine, knee flexed 20°
• Attempt to elevate lateral facet by pushing down medially
• Elevation to less than neutral means tight lateral tissue
• 0-20° Elevation is normal
12 2/5/2020
• X-Rays - Fleck of Bone medially • CT scan • TT – TG - 90° - TT ˂20mm lateral to mid trochlea of femur • MRI • Bone contusion LFC • MPFL tear • Articular damage
13 2/5/2020
14 2/5/2020
COLLATERAL DAMAGE !
15 2/5/2020
CT SCAN with FRACTURE
TREATMENT
- Non-Surgical
- Surgical
16 2/5/2020
NON-SURGICAL TREATMENT
• PT is often successful
• Initially focus on VMO strengthening
• Stretching also important
Achilles ٭ Hamstrings / Quads ٭ IT Band ٭ LAT Retinaculum ٭
• Closed chain exercises
• Core stability
• Functional Alignment
• Braces, orthotics for pronation, taping
Surgical Treatment
Proximal Realignment
Distal Realignment
Trochleoplasty
SURGICAL CONSIDERATION
• Patient Age
• Level of Activity
• Condition of Joint
• Origin of Deficiency - May be combination of alignment and soft tissue injury
17 2/5/2020
PROXIMAL REPAIR AND REALIGNMENT
• Repair ligament at point of injury • Anchors used to fix ligament to femur or patella • Recommended: • 1) In chronic case with failed conservative Rx • 2) Acute Instability with loose chondral fragment • If combining with TT transfers; do transfer first, then tension ligament
RECONSTRUCTION OF MPFL
• Not for pain, arthritis, or to correct malalignment
• Do not over tighten; leads to more pain and arthritis
PROCEDURE FOR MPFL
• Scope knee
• Harvest graft
• Place tunnels in patella
• Secure graft to patella
• Tension graft
• Fix graft to femur
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19 2/5/2020
20 2/5/2020
MEDIAL IMBRICATION AND VMO ADVANCEMENT
• First described procedure was huge • Large lateral release • Large lateral advancement
• Mini open with small lateral release proved more reliable
• Can now medially imbricate with scope
• Mention of lateral release • Never isolated procedure
21 2/5/2020
DISTAL REALIGNMENT
• Abnormal trochlea or patella alta • Transfers tibial tubercle distally and medially • Corrects Q-Angle • TT / TG Index corrected • Good results 89 – 93%
22 2/5/2020
Lift tubercle and shift medially
TROCHLEOPLASTY • 1ST Described in 1915 • Modified over the years • Results in arthritis
23 2/5/2020
SUMMARY Restore normal mechanics
Intact but attenuated MPFL – Imbrication
Reconstruct MPFL • MPFL and retinaculum attenuated • Congenital Dislocation • Severe ligamentous laxity Large Q Angle / Trochlea Dysplasia Tibial tubercle transfer
Lateral release never isolated procedure
Cartilage Injury • Meniscus Tears
• Articular Cartilage Injuries
24 2/5/2020
Mechanism of Injury •Trauma •Ligament / Fractures •Twisting •Squatting
Symptoms / Exam
• Intra – articular swelling • Pain on joint line • Lock / loss of extension • Pain with McMurray’s • Int/ext rotation of tibia
Knee X-Ray
25 2/5/2020
MRI Showing A Meniscus
26 2/5/2020
Treatment
•Arthroscopy •Debridement •Repair
Meniscal Repair
• Location of tear critical • White on red • Red on red
27 2/5/2020
Return to Sports
•Resect – 10 to 14 days •Repair – 4 to 6 months
Osteochondritis Dissecans
Definition •Condition in Which Portion of Subchondral Bone Undergoes Partial or Complete Separation From Its Bony Bed •Males/Females – 2/1 •Trauma Or Vascular Origin
28 2/5/2020
Osteochondritis Dissecans (OCD)
Mechanism of Injury - Lesion is Pre-Existing - Twisting Injury Dislodges Piece
Osteochondritis Dissecans
Physical Exam - Pain - Swelling - Locking Sensation, Popping - Loose Body
29 2/5/2020
Osteochondritis Dissecans
Radiology •X-ray to Assess Location, Number of Fragment •MRI Useful to Measure, Size, Depth, Condition of Articular Surface
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31 2/5/2020
Osteochondritis Dissecans
Treatment Postop •NWB 6 to 8 weeks •Gradual Return to WB Over 3 weeks •Serial X-rays to Determine Incorporation •Return to Sports – 4 to 6 months
Tendon Ruptures
Overview - Quadriceps Tendon - Patellar Tendon
32 2/5/2020
Quad Tendon Rupture
Method of Injury •Eccentric Contraction of Quad (i.e. Recovering From Tripping) •Rupture Intrasubstance or From Proximal Pole Patella •Increase Risk with D.M., Gout, Chronic Steroids, Dialysis
Quad Tendon Rupture
Physical Exam •Immediate Severe Pain and Swelling •Persistent Buckling, Cannot Climbs Stairs •Palpable Defect •Complete Tear – Cannot SLR Incomplete – Extensor Lag
Quad Tendon Rupture
Radiology •Low Patella, Patella Baja •Avulsion Fracture •Soft Tissue Swelling •MRI Will Show Tear, Used in Equivocal Cases
33 2/5/2020
Quad Tendon Rupture
Treatment •Rarely Non-Surgical •Majority Require Surgery •Slow Return to Full Motion •Return to Sports 6 to 9 months
Patella Tendon Rupture
Mechanism of Injury •Similar to Quad Tendon •Also Seen in Jumping Sports •Bilateral Ruptures Seen in Patients With Systemic Diseases
34 2/5/2020
Patella Tendon Rupture
Physical Exam •Defect Below Patella •Cannot Extend Leg Actively •Severe Pain, Inability to Walk
Patella Tendon Rupture
Radiology •X-rays Reveal Patella Alta, High Riding Patella •MRI Only For Equivocal Cases or Suspicion of Other Injuries
35 2/5/2020
Patella Tendon Rupture
Treatment •Incomplete Tear Rare, Could Immobilize 4 to 6 weeks •Majority Require Surgery •Auxiliary Wire to Protect Repair •Begin Motion 3 Weeks Postop
36 2/5/2020
Patellar Tendon Rehabilitation
• Straight leg brace at discharge • WBAT with crutches • May begin early motion if good repair and auxiliary wire used • Usually do not return to full sports activity for 6-9 months
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