Recurrent dislocation of patella DR, MOHAMMED BASHEER
- 3. Can follow a violent initial dislocation BUT
- 4. If a minor trauma causes dislocation
- 5. THINK OF one or more underlying anatomic abnormalities
- 6. The underlying pathologic condition causes An abnormal excursion of the extensor mechanism over the femoral condyles
- 9. Pulls laterally to the frontal plane of the femur At an angle of 7 to 10 degrees.
- 10. Has two parts Vastus medialis longus Pulling at 15 to 18 degrees medially
- 11. Vastus medialis obliquus Pulling at a relatively horizontal 50 to 55 degrees medially
- 12. Vastus medialis obliqus muscle The primary function is to stabilize the patella against the lateral pull of the vastus lateralis
- 13. ■ The largest sesamoid bone in the body. The quadriceps tendon inserts on the superior pole The patellar ligament originates from the inferior pole of the patella.
- 14. ■ Has seven articular facets The lateral facet is the largest (50% of the articular surface). ■The articular cartilage may be up to 1-cm thick.
- 15. Increases the mechanical advantage and leverage of the quadriceps tendon Aids in nourishment of the femoral articular surface Protects the femoral condyles from direct trauma
- 16. ■The geniculate arteries, which form an anastomosis circumferentially around the patella.
- 17. The distal femur broadens from the cylindrical shaft Has two curved condyles separated by an intercondylar groove.
- 18. ■The medial condyle extends more distally and is more convex than the lateral femoral condyle. This accounts for the physiologic valgus of the femur.
- 20. Shape of the patella Femoral sulcus Patellar tendon of appropriate length Normally tensioned medial capsule reinforced by the patellofemoral and patellotibial ligaments.
- 21. Incompetence of the medial patellofemoral ligament (MPFL). Main factor that results in recurrent patellar dislocation is An extra synovial ligament
- 22. Static and dynamic forces tend to displace the patella laterally.
- 23. First described by Brattström An angle formed by the line of pull of the quadriceps mechanism and that of the patellar tendon as they intersect at the center of the patella.
- 24. Angle is represented by the intersection of a line drawn from the anterior superior iliac spine to the center of the patella with a second line drawn from the center of the tibial tuberosity to the center of the patella
- 25. With the patient supine knee flexed 30 degrees with a bolster behind the knee,
- 27. Measurement to be accurate, the patella must be centered on the trochlea by flexing the knee 30 degrees
- 28. In males --- 8 to 10 degrees In females 15 ± 5 degrees
- 29. This valgus angle gives a lateral force vector to the patellofemoral joint as the knee is extended.
- 30. Genu valgum Increased femoral anteversion external tibial torsion Laterally positioned tibial tuberosity Tight lateral retinaculum.
- 31. By internally rotating the femur on a fixed tibia
- 32. Any factors that increase the Q angle can be a contributing factor in recurrent patellar dislocation
- 33. An accurate history – one of the most important diagnostic tools.
- 34. TO DIFFERENTIATE BETWEEN HABITUAL AND RECCURENT DISLOCATION
- 35. HABITUAL FLEXION IS ALWAYS COMPLETED WITH DISLOCATION PATIENT HAS NO COMPLAINT
- 36. Patellar problems can mimic various “internal derangements” of the knee
- 37. Diffuse pain around the knee that is aggravated by going up and down stairs or hills. The pain usually is located anterior in the knee and often is described as an aching pain with intermittent episodes of sharp, severe pain.
- 38. A feeling of insecurity in the knee “Giving way” or “Going out” of the knee may be present. Patellar crepitation and swelling
- 39. Patellofemoral crepitus An effusion may be present.
- 40. The examination begins by observing the patient’s patellar height, with the patient in the seated position. An upward tilt indicates patella alta.
- 42. Stand in front of the seated patient while the patient slowly extends the knee. A positive J sign (slight lateral subluxation of the patella as the Knee approaches full extension)
- 43. Examin with the knee relaxed in the extended position.
- 44. When the quadriceps muscle is tightened, motion of the patella is examined. Normally, the patella should move more superiorly than laterally
- 45. provide 60% of the medial stabilization Applying an infro laterally directed stress while palpating the ligament
- 46. By applying pressure to the patella and manually displacing it medially, laterally, superiorly, and inferiorly in the trochlear groove. Anterior knee pain Patellofemoral pathologic condition
- 47. Holds the relaxed knee in 20 to 30 degrees of flexion and manually subluxes the patella laterally. When the test is positive, the patient suddenly complains of pain and resists any further lateral motion of the patella
- 49. Visually divide the patella into four quadrants and passively moves the patella medially and then laterally, measuring the amount of excursion in the patellar quadrants.
- 50. Normally, passive patellar glide is one to two quadrants medially and laterally. Excessive lateral retinacular tightness is indicated by limited medial passive patellar glide
- 51. The examiner’s fingers are placed along the medial side of the patella with the thumb on the lateral aspect. Inability to raise the lateral facet to the horizontal plane or slightly past indicates excessive lateral retinacular tightness done with the knee in 20 degrees of flexion.
- 52. Tenderness along the medial or lateral facets of the patella may be noted with direct palpation of the facet as the patella is manually subluxed and rotated to expose these articular surfaces. Indicate a pathologic condition of the articular cartilage
- 53. Thigh circumferences measured proximal to the patella
- 54. Other joints should be examined for hyperlaxity. Hyperextension of the knees or elbows past 10 degrees, Ability to touch the thumb passively to the forearm, Hyperextension of the metacarpophalangeal joint of the index fnger, and multidirectional laxity of the shoulder joint
- 55. 1.BEIGHTON “S CRITERIA 2.WAYN- DAVIS CRITERIA
- 56. 1. FEMORALANTEVERSION 2.TIBIALTORSION 3. Q ANGLE 4. GENUVALGUM
- 60. AP and lateral views of the knee An axial (sunrise) view of both knees .
- 61. May reveal a bipartite patella which is a variant of normal. An osteochondral fracture of the medial patellar edge can be seen Loose bodies or osteochondral fractures
- 62. Hughston 55 degrees of knee flexion: Sulcus angle, patellar index ■ Merchant 45 degrees of knee flexion: Sulcus angle, congruence angle ■ Laurin 20 degrees of knee flexion: Patellofemoral index, lateral patellofemoral angl
- 66. determine patella alta.
- 67. Knee flexed 30 degrees, A line extending through the intercondylar notch should just touch the lower pole of the patella
- 69. Length of the patellar tendon (LT) and the diagonal length of the patella (LP) had a ratio of 1.0 with less than 20% variation. Patella alta is likely to be present if LT exceeds LP by more than 20% (ratio of ≥1.2)
- 71. lateral radiograph Trochlear depth measured 1 cm from top of groove Should be ≥5 mm
- 73. . A “crossing sign,” when the anterior cortical outline of the condyle intersects the trochlear outline, indicates a dysplastic sulcus, Trochlear “bump” when the trochlear line extends anterior to the femoral cortex
- 75. Type A: Crossing sign is present Trochlea is shallower than normal, Still symmetric and concave.
- 77. Type B: Crossing sign and trochlear spur Trochlea is flat or convex in axial images.
- 79. Type C: Crossing sign plus Double-contour sign representing sclerosis of the subchondral bone of the medial hypoplastic facet On axial CT views, lateral facet is convex.
- 82. Type D: Combination of all signs— Crossing sign, Supratrochlear spur, and Double contour sign; Cliff pattern on axial CT views
- 84. The length of the articular surface of the patella to that of the length measured from the articular surface of the tibia to the inferior pole of the patella. Normal ratios with this measurement were between 0.54 and 1.06
- 86. MRI or CT indicated An axial view at the superior trochlear groove is used to evaluate dysplasia; Superimposed views are used to evaluate malalignment.
- 87. Tibial tubercle–trochlear groove (TT-TG) Distance of more than 20 mm on CT or MRI may indicate malalignment and necessitate distal realignment
- 89. Surgery is not needed in all patients Good results have been achieved with a conservative exercise treatment program in moderately active individuals. A rehabilitation program to strengthen the quadriceps muscle is prime.
- 90. More than 100 surgical procedures The key to successful surgical intervention is correctly identifying and treating the pathologic anatomy .
- 91. Patella alta Trochlear dysplasia Trochlear bump
- 92. Tibial tubercle Femoral anteversion External tibial torsion genu valgum hyperpronation
- 93. Dynamic (VMO dysfunction) Static Incompetent MPFL generalized hyper laxity Over constraint
- 94. Insall index >1 : 2 Distalization
- 95. Crossing sign Trochlear bump Sulcus angle >145 degrees MPFL reconstruction Trochleoplasty
- 96. Q angle > 20 degrees TT-TG > 20 mm Anteromedialization of tuberosity
- 97. Thigh-foot angle > 30 degrees Rotational osteotomy
- 98. External tibial torsion, genu valgum, hyperpronation Observation Orthotics and rehabilitation
- 99. Dynamic (VMO dysfunction) TT-TG <20 mm Rehabilitation
- 100. Incompetent MPFL or generalized hyperlaxity Lateral glide 3 quadrants Medial imbrication if good tissues or MPFL reconstruction
- 101. Overconstraint Lateral tilt (excessive lateral pressure syndrome) Lateral release
- 102. No single operation is universally successful in correcting recurrent patellar dislocation and subluxation. The operation must be chosen in so far as possible with the needs of the individual patient
- 103. Low-risk, high-reward procedure Procedures that involve transplantation of the tibial tuberosity are contraindicated until the proximal tibial physis has closed. Premature closure of the anterior portion of this physis can lead to genu recurvatum,
- 104. During all operative procedures , a thorough arthroscopic inspection of the articular surfaces and intraarticular structures is important
- 105. To treat associated pathologic problems Observe patellofemoral tracking through a superolateral portal
- 106. Symptomatic chondral changes inferiorly and laterally can be improved by antero medialization of the tuberosity, transferring the stress proximally and medially.
- 107. Symptomatic chondral changes of the medial facet are exacerbated by overtightening medially
- 108. When surgery is indicated, the best approach is an MPFL reconstruction.
- 109. If grade 3 chondral changes are present, an oblique osteotomy for distal realignment should be considered.
- 110. Afer completing the realignment procedures, the Q angle as measured with a goniometer should be less than 15 degrees but more than 10 degrees
- 111. Insall index measures more than 1.2 on preoperative radiographs, The tibial tuberosity should be transferred distally and medially to create an Insall index of approximately 1.2.
- 112. LOW RISK—LOW REWARD LOW RISK—HIGH REWARD HIGH RISK—HIGH REWARD
- 113. Medial repair/imbrication Lateral release
- 114. MPFL reconstruction Elmslie-Trillat procedure
- 115. Fulkerson distal realignment Rotational high tibial osteotomy Trochleoplasty Grooveplasty 3-in-1 procedure—extensor mechanism realignment + VMO advancement + transfer of the medial third of the patellar tendon to the MCL
- 116. 1. An isolated procedure for parapatellar pain secondary to excessive lateral pressure syndrome (i.e., negative patellar tilt and less than one quadrant passive medial patellar glide) In a combination realignment procedure,
- 117. An effective lateral release must include release of the retinaculum from the distal third of the vastus lateralis down to the tibial tuberosity to include the lateral patellofemoral and patellotibial ligaments
- 118. Lateral release can be done as an open or arthroscopic procedure. most are now done arthroscopically. This allows complete exploration of the knee joint, which is important in any operation for patellar subluxation or dislocation.
- 119. May increase risk for both medial and lateral patellar subluxation
- 120. Indications Medial laxity with or without trochlear dysplasia, Fine-tuning of distal realignment procedures, in skeletally immature patients
- 121. MINI OPEN MEDIAL REEFINGAND ARTHROSCOPIC LATERAL RELEASE
- 123. To produce a stable patellofemoral joint, the site of injury of the MPFL must be identifed repaired, reinforced, or reconstructed
- 124. Femoral attachment can be repaired and reinforced by use of the adductor magnus tendon
- 128. Chronic instability with a Q angle of less than 20 degrees or an extensively damaged MPFL Semitendinosus hamstring tendon graft technique.
- 129. the most widely used method of controlling patellar dislocation.
- 130. Q angle of more than 20 degrees anterior tibial tuberosity-to-trochlear groove distance of more than 15 mm lateral chondromalacia.
- 131. Described transfer of the tibial tuberosity in a relatively posterior position
- 132. Patellofemoral contact stress late osteoarthritis of the patellofemoral joint. should not be used in children with open proximal physis
- 133. Hauser’s method has been modifed by several authors Trillat et al Cox Brown et al
- 134. Anteromedialization for maltracking with associated chondral changes
- 135. Distal sof-tissue realignment procedures described by Roux, Goldthwait, and Galeazzi probably best avoided
- 136. Anterior displacement of the tibial tuberosity in realigning the patellofemoral mechanism.
- 137. Modifcations of the Elmslie-Trillat procedure The procedure consists of lateral retinacular release, medial retinacular plication, and medial transfer of the tibial tuberosity.
- 138. An Insall index of less than 1.2 Grade 2 or less chondromalacia noted at arthroscopy. For the best cosmetic result, an arthroscopic lateral release is done first
- 139. Fulkerson and by Brown et al. Transfers the tuberosity anteriorly and medially. Indicated when grade 3 or 4 chondromalacia is associated with recurrent dislocations.
- 141. Stress risers and stress fractures A flat (Elmslie-Trillat) osteotomy had significantly higher failure rates than the oblique osteotomy technique. Not indicated for athletes
- 142. Signifcant patella alta With an Insall index of more than 1.2, Medial and distal transfer of the tuberosity is indicated.
- 145. For skeletally mature patients with instability associated with severe rotational deformity, Better functional results and more normal gait patterns than proximal or distal realignment procedures.
- 146. Indications for high tibial osteotomy Thigh-foot angle of more than 30 degrees and Tubercle-sulcus angle of more than 10 degrees
- 147. The primary goal is to improve patellar tracking by decreasing the prominence of the trochlea and creating a new groove with normal depth
- 148. Sulcus-deepening Technically demanding Indications: High-grade trochlear dysplasia with patellar instability and/or abnormal tracking.