lonnie e. paulos, md medical director the andrews-paulos research & education institute
DESCRIPTION
Lonnie E. Paulos, MD Medical Director The Andrews-Paulos Research & Education Institute Gulf Breeze, FL. Knee Cap. The patella articulates with the femur…. It’s a joint. Patella. Sulcus. Femur. To function properly any joint must be. Aligned (Straight) Congruent (fits together) - PowerPoint PPT PresentationTRANSCRIPT
Lonnie E. Paulos, MD
Medical Director
The Andrews-Paulos
Research & Education Institute
Gulf Breeze, FL
Knee Cap
The patella articulates with the femur….
It’s a jointPatella
Sulcus
Femur
To function properly any joint must be...
Aligned (Straight)
Congruent (fits together)
Stable (norm ligaments)
Side view
Sunshine view
The patella-femoral joint rarely has all three
The most common knee problem seen by doctors
The majority of people have a patella-femoral joint that is either...
Mal-aligned (not straight)
Incongruent (doesn’t fit)
Too loose (weak ligaments)
Too tight (contracted ligaments)
All of the above (miserable mal-alignment)
? Mean
?Malalignment
• Determined by skeletal alignment. Develops from hip to foot (genetics)
• Functional alignment which requires normal muscle balance and conditioning during activities
Patella-femoral alignment is
There is little or no consensus as to what constitutes malalignment or what treatment should be employed for symptomatic patients...
The result is inconsistent treatment, unpredictable outcomes and
occasionally increased symptoms
The “Maligned” Patella!
Anterior iliac spine
Med.Lat.
• Historically, Q angle has been measured with knee in extension
• Has never demonstrated significance
• ? Sulcus location (Patella-Sulcus alignment)
Tibial
tubercle
Is determined by hip, thigh, leg and foot alignment which can be measured by radiographs (CT scans) and estimated by physician examination.
Patella-Sulcus Alignment
Computerized Axial Tomography (CT Scan) Tubercle/Sulcus Position
• Full extension
• May identify abnormalities that reduce with flexion
• Precise measures
• Distance between tibial tubercle and trochlear sulcus
• >9 mm indicates lateralization of tibial tubercle
Physical ExaminationSkeletal Alignment
• Hip rotation
•Knee valgus or varus
• Knee ROM
• Patella-Sulcus angle
•Foot alignment
Axial Alignment
Knee valgus or varus• Lateral insertion of patella tendon
• Normal 5° valgus
Saggital Alignment
• Hyper-extension 3° to 5° normal
• Flexion 140° to 150° normal
Tubercle-Sulcus Angle
• Flexed knee Q angle
• Perpendicular to transepicondylar axis
• Patella center to tubercle
• Knee flexed 90º
• Normal = 0º, abnl > 10º lat.
Kolowich, Paulos et. al 1990 AJSM 18:359-365
Rotational Alignment
Hip Rotation
• Ext. rotation Int. rotation
•Hip assumes neutral position for gait so toes point forward
•Diff > 60° no external rotation => Abnormal
Hip Internal
Hip External
Rotational Alignment
Thigh-foot angle
• Normal = 15° ext.
• > 30° - consider surgery
Foot Alignment
Pronation
• Assoc. ext. tibial rotation and compensatory valgus
?Incongruence
STRUCTURAL&
ARTICULAR
Patellofemoral Imaging
• Radiographs – AP, lateral, axial
• Computed Tomography
• Magnetic Resonance Imaging
• Helpful in evaluation, but diagnosis of subluxation or dislocation is clinical, not radiographic
Patellofemoral ImagingAxial Views
Laurin - 20º
Merchant - 45º• Joint congruency
• Trochlear depth• Lateral buttress
• Tilt• Subluxation
Patellofemoral Joint Congruence
• Femoral sulcus shape depth; lateral condylar height
• Patella shape facet size; angle
• Patella height alta; infera
Alignment Growth Congruence
“Geometric restraints”
Wyberg
Articular• Grade 0: healthy cartilage• Grade 1: cartilage soft spot or blisters• Grade 2: minor tears visible in the cartilage• Grade 3: deep crevices (>50% of cartilage layer)• Grade 4: exposed bone
“Chondromalacia”
?Too Loose
Passive Laxity
Determined by
Ligament integrity
Geometry (Congruence)
Patellar Glide
0º Flexion
Determines
Medial/Lateral
Restraint
30º flexion
Congruence
Patellar Glide Test
3 to 4 quad glide too loose
Passive Patellar Tilt
Determines lateral and medial Restraints
Female + 5º = +10ºMale 0° + 5º
Tilt too loose
?Too tight
• Lateral retinacular tightness – 0 or negative tilt
• Lateral patella pain• Radiographic patella tilt/overhang ±• Arthroscopic lateral tracking with
lateral patellofemoral wear ±
Lateral Patellar Compression Syndrome (LPCS)
NOT X-RAY Diagnosis!
Primary vs. Secondary
Lateral Trackers LPCS Time
LPCS Hypermobile-Lateral Tracker
?All of the above
Miserable Malalignment!
Internal femoral torsion External tibial torsion• Dysplastic patella shape• Dysplastic femur sulcus T/S angle Lateral tilt Medial glide• Flat feet
Accurate Evaluation
Treatment?
Joint reaction force with congruence
Consensus Opinion
[patella-femoral maladies]
muscle strength + balance
“envelope of function” Scott Dye
function=
Time
“Envelope of FunctionCompensated
Compensated
Mild MajorLimb Malalignment
Excellent
Bad
Strength and
Balance
FunctionalCapacity
Over-use
Obesity
Accident
Dis-use
?Surgery [Malalignment] + [Patholaxity] + [Incongruence]
Physical [Muscle condition] + [Activity modification]Therapy
Treatment
1st Choice when treating P/F problems is conservative (non-surgical) treatment
Surgery
Usually
Typical Non-Surgical
• Neuromuscular facilitation
• Activity modification
• Weight loss
• Orthotics
• Bracing & Taping
But . . .
Dynamic (compensatory) Alignment
Maximum Compensation
Minimum Compensation
•Patient strides forward, one leg is lifted while full weight is on the other leg. The swing leg is subjected to rotational hip compensation, mechanical alignment, and T/S angle positioning of the tibia tubercle to the femoral sulcus just prior to heel strike.
•Much like “lining up a putt” in golf, the patella is aligned with the sulcus.
•At heel strike, the femur engages the patella as the hip and femur finish rotating to the mid-point between internal and external hip rotation in order to keep the foot pointed forward during the foot-flat and toe-off phases of gait.
•The femoral sulcus is pre-positioned in its relationship to the tibial tubercle and actually engages the more passive patella. If this fails to occur, depending on the static and geometric restraints present, the patella will track lateral and spontaneously subluxate or dislocate during gait just prior to the foot-flat phase.
• Quadriceps unit (mass action vector)
• PES anserine group (reduces T/S angle)
• Hip Abduction/Adduction (rotation)
Dynamic Restraints?
Patellofemoral Joint
Functional Rehabilitation• Isometrics• Straight leg raises• Leg presses (standing)• Cycle• Swim• Low impact jumping• Stretch cords
• Progressive step-ups (8” max)
• Increase passive hip rotation & strength!
Patella Forces
Knee Flexion Angle
Standing
Sitting
100°0°
Indications for Surgery
• Failure of conservative care
• Progressive P/F arthritis with pain
• Recurrent subluxations / dislocations
• Debilitating symptoms with daily activities
?
Amount and type of surgery depends on the patient’s anatomy and severity
of problems
[malalignment] + [patholaxity] + [incongruence]
The surgeon should choose the surgical procedure with the least risk
and highest chance of success based on patient anatomy
Not the easiest!
Proximal + Distal Realignment
Proximal Realignment
Lateral Release
Synovectomy/Chondroplasty
High Risk
Low Risk
Procedure selected depends on age, goals, informed consent
Synovectomy/Chondroplasty?
• Pain + crepitation only
• Short term symptoms
• No instability
?Lateral Release
☼
+
Primary Indication for Isolated Lateral Release
• Failed conservative treatment
• A negative or neutral passive patellar tilt (LPCS)
• NO or minimal instability or malalignment
Proximal Realignment(at the patella)
Indications
• Subluxating/dislocating patella with medial laxity
• Minimal patella alta
• Minimal malalignment
• Failure of patella to center after lateral release
• Failure to improve after lateral release (6 to 9 mos.)
+ ?
Proximal Realignment Procedures
Medial plication• Mini-open
• Arthroscopic
Rarely Need• VMO advancement
• MPFL reconstruction or replacement
?Distal Realignment Procedures
Indications• Subluxating /
dislocating patella T/S angle >15º• Patella alta• Patella infera• Mal-alignment
(at the tibia)
+
Hauser Procedure
• Medial
• Posterior
Fulkerson Procedure
• Medial
• Anterior
Elmsley-Trillat Procedure• Flat cut • 5-6 cm tubercle shingle, intact
distally + med. sleeve• Rotate tubercle medially 1-1.5cm• Check tracking, tubercle sulcus
angle 0°• Fix with 2 screws A B C
1990 StudyFailed vs. successful lateral release
Kolowich-Paulos
AJSM-1990
Bench Mark Study
Lateral Patella Compression Syndrome (LPCS)
Proximal-Distal Results256 patients
• 5 yr F/U• > 80% satisfied• < 5% recurrence rate
BUT…• Gradual symptoms @ 24 mos. >30%
esp. for extreme T/S angles
Mid-90’s
Severe femoral-tibial torsion
?
Enlightened
• Stan James, M.D.
• Robert Tiege, M.D.
• Peter Stevens, M.D.
“Torsional Limb Mal-alignment”
Bruce, Stevens
J Pediatr Orthop, Jul-Aug 2004
Tiege, Robert
Meisler, James
Am J Ortho, Feb 1995
New Distal Procedure
De-Rotation high tibial osteotomy
D-HTO
Corrects significant external tibial torsion
and associated extreme T/S angle
A B C
[T/F Angle] – [T/S Angle] = + 15°<
0° T/S Angle
Never Negative
Miserable Malalignment
• Femoral malrotation ≥ 30º• Derotational osteotomy femur
• External tibial torsion ≥ 30º• Derotational osteotomy tibia
• Supratubercular• Mid-diaphyseal (immature)
• Lateral release• ± medial ligament repair
[Int – Ext]
2
2003
A crossover study was conducted of patients with dislocating patellae and significant torsional lower leg deformity who underwent a (D-HTO).
The results were compared to patients with similar alignment and dislocating patellae who underwent The Elmsley-Trillat Fulkerson (ETF) proximal-distal realignment.
Questionnaires1. Kujala scoring sheet
• Specific to patella-femoral joint
• Validated 1993 + 2003
• Reliability = 0.86, Consistency = 0.82
• Ceiling 19%, Floor 0%
2. The Knee and Osteoarthritis Score (KOOS)
• Patient based outcomes following TKA and osteoarthritis
3. The RAND 36-Item Health Survey (ver. 1.0)
• 8 Health concepts
“Gun-sight” CAT Scan
Confirmed Torsional Alignment
Instrumented Treadmill
• 51 - Retro-reflective markers
• 8 - Digital motion analysis - TM cameras
• 4 - 3D force transducers
• Data low passed filtered (Butterworth dig. Filter)
• Visual 3D real time software
Results
Stride KinematicsGroup I Group II
Surgery Non-Surgery
Difference (SD)
Surgery Non-Surgery
Difference (SD)
pvalue
Total Stride Time (s) 0.671 0.673 -0.002 (.005)
0.665 0.680 -0.014 (.005)
0.004
Single Stance Time (s) 0.380 0.382 -0.002 (.005)
0.374 0.388 -0.014 (.005)
0.004
Double Stance Times (s) 0.144 0.147 -0.002 (.004)
0.153 0.138 0.015 (.007)
0.004
Total Limb Contact Time (s) 0.289 0.293 -0.004 (.009)
0.277 0.306 -0.028 (.011)
0.004
Shown are means and mean differences (standard deviation) of surgery-side limb minus the non-surgery side limb. The p value is from an independent samples Fisher-Pitman permutation test to allow for skewness in the difference score distributions. The double stance time value indicates which limb was forward during each period of double stance within each stride.
Near Equal Significant Non-Significant
Foot-External Rotation
Significant variability
Group II (Proximal-distal)Group I (Derotational high tibial osteotomy)
Results
Kajula and Knee and Osteoarthritis Scale Scores Preoperatively* and at Most Recent Follow-up
Evaluation
Preoperative Follow-up p Value Preoperative Follow-up p Value
p ValueGroup I vs.
Group IIFollow-up
Kajula ScoreKOOS Scores: Pain Symptoms Activities of Daily Living Sports and Recreation Quality of Life
50 + 23
54 + 2648 + 2167 + 2224 + 2417 + 19
80 + 10
85 + 1281 + 1685 + 1558 + 2862 + 24
< 0.001
< 0.001< 0.001< 0.0010.002
< 0.001
55 + 22
57 + 2249 + 1862 + 2531 + 2931 + 22
65 + 16
67 + 1862 + 1773 + 1944 + 3035 + 25
NS
NS0.020.03NSNS
0.010.0050.008NSNS
0.005
All values are mean + standard deviation. NS = not significant.*There were no significant differences at the preoperative evaluation between Group 1 and Group 2. **The between group comparisons were done using a multivariable linear regression comparing the group follow-up scores, controlling for both the preoperative scores and time to follow-up evaluation, with p values adjusted for six multiple comparisons using Hochberg’s procedure.
Results
SF-36 Scores Preoperatively and at the Most Recent Follow-up Evaluation
Group 1 (Derotational high tibial osteotomy) Group 2 (Proximal-distal)
SF Factor Preoperative Follow-up P Value Preoperative Follow-up p value P valueGroup I vs.
Group IIFollow-up
Physical FunctioningRole Limitations Due to Physical HealthRole Limitations Due to Emotional ProblemsEnergy/FatigueEmotional Well-BeingSocial FunctioningPainGeneral Health
47.1 ± 25.420.8 ± 41.075.0 ± 43.955.4 ± 21.956.0 ± 19.145.8 ± 22.951.5 ± 22.534.2 ± 27.6
87.9 ± 22.4100 ± 0.0
94.4 ± 23.286.7 ± 15.188.0 ± 16.585.4 ± 14.695 ± 10.0
78.3 ± 22.4
< 0.001< 0.001
NS< 0.001< 0.001< 0.001< 0.001< 0.001
44.2 ± 30.365.4 ± 48.064.1 ± 48.660.8 ± 24.768.6 ± 20.359.6 ± 22.472.5 ± 16.451.4 ± 32.2
50.0 ± 27.178.8 ± 41.274.4 ± 44.265.8 ± 22.268.0 ± 20.965.0 ± 19.177.7 ± 13.153.4 ± 28.5
NSNSNSNSNSNSNSNS
0.0040.001NS
0.007< 0.001< 0.001< 0.0010.001
All values are mean + standard deviation. NS = not significant.*Between group comparisons were done using a multivariable linear regression comparing the follow-up scores, while controlling for the preoperative scores and time to follow-up evaluation.
How much better is D-HTO vs. Tubercle Transfer?
JAW DROPPING!
In closing:Patella femoral surgery must be undertaken only with a thorough understanding of the problem, after an accurate evaluation, exhaustive conservative care and with the utmost caution.
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