1. Lonnie E. Paulos, MD Medical Director The Andrews-Paulos Research & Education Institute Gulf Breeze, FL

2. Knee Cap

3. The patella articulates with the femur…. It’s a joint Patella Sulcus Femur

4. To function properly any joint must be... Aligned (Straight) Congruent (fits together) Stable (norm ligaments) Side view Sunshine view

5. The patella-femoral joint rarely has all three The most common knee problem seen by doctors

6. 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

7. ? Malalignment

8. 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

9. 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!

10. 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 tubercl e

11. 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

12. 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

13. Physical Examination Skeletal Alignment Hip rotation Knee valgus or varus Knee ROM Patella-Sulcus angle Foot alignment

14. Axial Alignment Knee valgus or varus Lateral insertion of patella tendon Normal  5° valgus

15. Saggital Alignment Hyper-extension 3° to 5° normal Flexion 140° to 150° normal

16. 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

17. 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

18. Rotational Alignment Thigh-foot angle Normal = 15° ext. > 30° - consider surgery

19. Foot Alignment Pronation Assoc. ext. tibial rotation and compensatory valgus

20. ? Incongruence STRUCTURAL & ARTICULAR

21. Patellofemoral Imaging Radiographs – AP, lateral, axial Computed Tomography Magnetic Resonance Imaging Helpful in evaluation, but diagnosis of subluxation or dislocation is clinical, not radiographic

22. Patellofemoral Imaging Axial Views Laurin - 20º Merchant - 45º Joint congruency Trochlear depth Lateral buttress Tilt Subluxation

23. 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

24. 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”

25. ? Too Loose

26. Passive Laxity Determined by Ligament integrity Geometry (Congruence)

27. Patellar Glide 0º Flexion Determines Medial/Lateral Restraint 30º flexion Congruence Patellar Glide Test 3 to 4 quad glide  too loose

28. Passive Patellar Tilt Determines lateral and medial Restraints Female + 5º = +10º Male 0°  + 5º  Tilt  too loose

29. ? 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!

30. Primary vs. Secondary Lateral Trackers LPCS Time LPCS Hypermobile-Lateral Tracker

31. ? All of the above

32. Miserable Malalignment!  Internal femoral torsion  External tibial torsion Dysplastic patella shape Dysplastic femur sulcus  T/S angle  Lateral tilt  Medial glide Flat feet

34. Accurate Evaluation Treatment?  Joint reaction force with congruence

35. Consensus Opinion [patella-femoral maladies] muscle strength + balance “envelope of function” Scott Dye function =

36. Time “Envelope of Function Compensated Mild Major Limb Malalignment Excellent Bad Strength and Balance Functional Capacity Over-use Obesity Accident Dis-use

37. ? Surgery  [Malalignment] + [Patholaxity] + [Incongruence] Physical  [Muscle condition] + [Activity modification] Therapy Treatment

38. 1 st Choice when treating P/F problems is conservative (non-surgical) treatment Surgery Usually

39. Typical Non-Surgical Neuromuscular facilitation Activity modification Weight loss Orthotics Bracing & Taping But...

40. Dynamic (compensatory) Alignment Maximum Compensation Minimum Compensation

41. 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.

42. Quadriceps unit (mass action vector) PES anserine group (reduces T/S angle) Hip Abduction/Adduction (rotation) Dynamic Restraints?

43. 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°

44. Indications for Surgery Failure of conservative care Progressive P/F arthritis with pain Recurrent subluxations / dislocations Debilitating symptoms with daily activities

45. ? Amount and type of surgery depends on the patient’s anatomy and severity of problems [malalignment] + [patholaxity] + [incongruence]

46. The surgeon should choose the surgical procedure with the least risk and highest chance of success based on patient anatomy Not the easiest!

47. Proximal + Distal Realignment Proximal Realignment Lateral Release Synovectomy/Chondroplasty High Risk Low Risk Procedure selected depends on age, goals, informed consent

48. Synovectomy/Chondroplasty? Pain + crepitation only Short term symptoms No instability

49. ? Lateral Release ¤ ☼ +

50. Primary Indication for Isolated Lateral Release Failed conservative treatment A negative or neutral passive patellar tilt (LPCS) NO or minimal instability or malalignment

51. 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.) + ?

52. Proximal Realignment Procedures Medial plication Mini-open Arthroscopic Rarely Need VMO advancement MPFL reconstruction or replacement

53. ? Distal Realignment Procedures Indications Subluxating / dislocating patella  T/S angle >15º Patella alta Patella infera Mal-alignment (at the tibia) +

54. Hauser Procedure Medial Posterior

55. Fulkerson Procedure Medial Anterior

56. 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

57. 1990 Study Failed vs. successful lateral release Kolowich-Paulos AJSM-1990 Bench Mark Study Lateral Patella Compression Syndrome (LPCS)

58. Proximal-Distal Results 256 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

59. Severe femoral-tibial torsion ?

60. 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

61. New Distal Procedure De-Rotation high tibial osteotomy D-HTO Corrects significant external tibial torsion and associated extreme T/S angle

62. ABC [T/F Angle] – [T/S Angle] = + 15° < 0° T/S Angle Never Negative

63. 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

64. 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.

65. Questionnaires 1. 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

66. “Gun-sight” CAT Scan Confirmed Torsional Alignment

67. 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

68. Results Stride Kinematics Group IGroup II SurgeryNon- Surgery Difference (SD) SurgeryNon- Surgery Difference (SD) p value Total Stride Time (s)0.6710.673-0.002 (.005) 0.6650.680-0.014 (.005) 0.004 Single Stance Time (s)0.3800.382-0.002 (.005) 0.3740.388-0.014 (.005) 0.004 Double Stance Times (s)0.1440.147-0.002 (.004) 0.1530.1380.015 (.007) 0.004 Total Limb Contact Time (s)0.2890.293-0.004 (.009) 0.2770.306-0.028 (.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 SignificantNon-Significant

69. Foot-External Rotation Significant variability

70. 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 PreoperativeFollow-upp ValuePreoperativeFollow-upp Value Group I vs. Group II Follow-up Kajula Score KOOS Scores: Pain Symptoms Activities of Daily Living Sports and Recreation Quality of Life 50 + 23 54 + 26 48 + 21 67 + 22 24 + 24 17 + 19 80 + 10 85 + 12 81 + 16 85 + 15 58 + 28 62 + 24 < 0.001 0.002 < 0.001 55 + 22 57 + 22 49 + 18 62 + 25 31 + 29 31 + 22 65 + 16 67 + 18 62 + 17 73 + 19 44 + 30 35 + 25 NS 0.02 0.03 NS 0.01 0.005 0.008 NS 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.

71. Results SF-36 Scores Preoperatively and at the Most Recent Follow-up Evaluation Group 1 (Derotational high tibial osteotomy) Group 2 (Proximal-distal) SF FactorPreoperativeFollow-upP ValuePreoperativeFollow-upp valueP value Group I vs. Group II Follow-up Physical Functioning Role Limitations Due to Physical Health Role Limitations Due to Emotional Problems Energy/Fatigue Emotional Well-Being Social Functioning Pain General Health 47.1 ± 25.4 20.8 ± 41.0 75.0 ± 43.9 55.4 ± 21.9 56.0 ± 19.1 45.8 ± 22.9 51.5 ± 22.5 34.2 ± 27.6 87.9 ± 22.4 100 ± 0.0 94.4 ± 23.2 86.7 ± 15.1 88.0 ± 16.5 85.4 ± 14.6 95 ± 10.0 78.3 ± 22.4 < 0.001 NS < 0.001 44.2 ± 30.3 65.4 ± 48.0 64.1 ± 48.6 60.8 ± 24.7 68.6 ± 20.3 59.6 ± 22.4 72.5 ± 16.4 51.4 ± 32.2 50.0 ± 27.1 78.8 ± 41.2 74.4 ± 44.2 65.8 ± 22.2 68.0 ± 20.9 65.0 ± 19.1 77.7 ± 13.1 53.4 ± 28.5 NS NS NS NS 0.004 0.001 NS 0.007 < 0.001 0.001 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.

72. How much better is D-HTO vs. Tubercle Transfer? JAW DROPPING!

74. 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. ¤