Patella Instability 1 st Time Dislocation

Transcription

1 Patella Instability 1 st Time Dislocation American Medical Society for Sports Medicine April 6, 2014 Beth E. Shubin Stein, MD Sports Medicine & Shoulder Surgery Hospital for Special Surgery

2 Beth E. Shubin Stein, MD Hospital for Special Surgery Disclosure: I DO NOT have a financial relationship with any commercial interest.

3 What is the Problem???

4 THIS IS THE PROBLEM

5 Factors contributing to stability Articular geometry Soft tissue stabilizers Static Dynamic Patella Stability

6 Patella Stability Articular geometry Trochlea Patella

7 Patella Stability Trochlear Dysplasia

8 Patella Stability Patella Alta

9 Patella Stability TT-TG

10 Patella Stability Soft tissue stabilizers Medial patellofemoral ligament

11 MPFL Anatomy Originates saddle between adductor tubercle and medial epicondyle Inserts medial patella Blends with the deep fascia of the VM the passive and dynamic stabilizers may act in concert

12 MPFL Biomechanics Restraint to lateral translation MPFL 60% Lateral retinaculum 10% Desio et al

13 Patella Stability Dynamic Stabilizers Vastus medialis

14 Acute Patellar Dislocation History 2 nd and 3 rd decade Twisting non-contact injury Rapid effusion Locking catching Men=Women *They do not tell you they dislocated

15 Acute Patellar Dislocation Physical Exam Effusion Tenderness and ecchymosis medially over adductor tubercle Apprehension*** R/O ACL, MCL injury Same MOI

16 Axial radiograph *best view for tilt or subluxation Lateral radiograph Patella height Trochlear morphology MRI Cartilage lesions Ligament damage TT-TG Imaging

17 Acute Patellar Dislocation MRI

18 Acute Patellar Dislocation Predisposing Factors Patella alta VMO dysplasia Increased Q angle Contracted ITB Valgus knee deformity Hypoplastic lateral condyle

19 Characteristics of Patients with Primary Acute Lateral Patellar Dislocation: their Recovery within the First 6 Months of Injury Atkin, Fithian et al AJSM 2000 Few patients had abnormal physical features, contradicting the stereotype of a overweight, sedentary, adolescent girl whose patella dislocates with little or no trauma

20 Natural History Non-Operative Treatment Epidemiology and Natural History of Acute Patellar Dislocation Fithian et al. Am J Sports Med : % after 1 st dislocation ~50% after 2 nd dislocation

21 What is the Problem? Chondral injury Medial facet patella Lateral trochlea

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23 Not always clear 1 st time dislocators Who Needs Surgery? Non op treatment (unless Osteochond fx/ loose body) **Recurrent dislocators Atraumatic Traumatic

24 Am J Sports Med Mar Predictors of recurrent instability after acute patellofemoral dislocation in pediatric and adolescent patients. Lewallen LW, McIntosh AL, Dahm DL.

25 Proximal realignment Patellar Instability Surgical Options Acute repair MPFL Open/Arthroscopic imbrication MPFL reconstruction Distal realignment Tibial tubercle transfer Both

26 Patellar Instability Surgical Options Proximal realignment Acute repair MPFL Open/Arthroscopic imbrication MPFL reconstruction Distal realignment Tibial tubercle transfer Both

27 Patellar Instability Surgical Options Proximal realignment Acute repair MPFL Open/Arthroscopic imbrication MPFL reconstruction Distal realignment Tibial tubercle transfer Both

28 Patellar Instability Surgical Options Proximal realignment Acute repair MPFL Open/Arthroscopic imbrication MPFL reconstruction Distal realignment Tibial tubercle transfer Both

29 Patellar Instability Surgical Options Proximal realignment Acute repair MPFL Open/Arthroscopic imbrication MPFL reconstruction Distal realignment Tibial tubercle transfer Both

30 Proximal realignment Patellar Instability Surgical Options Acute repair MPFL Open/Arthroscopic imbrication MPFL reconstruction Distal realignment Tibial tubercle transfer Both

31 Patellar Instability Surgical Options Proximal realignment Acute repair MPFL Open/Arthroscopic imbrication MPFL reconstruction Distal realignment Tibial tubercle transfer Both Trochleaplasty

32 MPFL Repair

33 MPFL repair Indications 1 st time dislocation loose body osteochondral fracture Goals Same as reconstruction Restore anatomy Restore biomechanics/function Optimize strength of fixation

34 Imaging MRI

35 Arthroscopy

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37 Results Acute MPFL Repair Salley et al AJSM 1996 Open MPFL repair 16 patients Ave follow-up 34 mos No recurrent dislocations

38 Results Acute MPFL Repair Ahmad et al AJSM 2000 Open MPFL and VMO repair 8 patients Ave f/u 3.0 years No recurrent dislocations Ave Kujala score was 91.9 Return to 86% of their pre-injury athletic level Subjective satisfaction was 96%

39 MPFL Reconstruction

40 Imaging MRI

41 MPFL Reconstruction

42 MPFL Reconstruction

43 Post Op Radiographs Pre-op

44 Results MPFL Reconstruction Steiner et al AJSM patients Multiple grafts Min 2yr f/u; mean 66.5 mos No recurrent dislocations 85% kujala; 91% lysholm G/E ** in patients with TROCHLEAR DYSPLASIA

45 20 patients Results MPFL Reconstruction The Docking Technique for Medial Patellofemoral Ligament Reconstruction Surgical Technique and Clinical Outcome Christopher S. Ahmad, MD, Gabriel D. Brown, MD, and Beth Shubin Stein,MD -AJSM 2009 Min f/u 24 mos; avg 31 mos No recurrent dislocations or subluxations Kujala 88; Lysholm 89

46 EUA

47 Arthroscopy

48 Proximal/ Distal Realignment

49 Proximal/ Distal Realignment

50

51 Thank You