Patellofemoral Instability Non-operative Treatment Andrew Gregory, MD, FAAP, FACSM Associate Professor, Orthopedics, Neurosurgery & Pediatrics Vanderbilt University Medical Center Disclosure I have conflicts of interest regarding this presentation. I will give a balanced presentation using the best available evidence to support my conclusions and recommendations. I do not intend to discuss an unapproved/ investigative use of a commercial product/device. Conservative Treatment Reduction Brief immobilization/ NWB (approx. 1 week) Xrays including sunrise views (looking for fractures of the medial patella/ LFC) MRI if unsure of diagnosis/ eval. of osteochondral fractures Aspiration/ Injection - if large hemarthrosis PTO brace for walking/ activity Ice scheduled NSAIDs scheduled Formal Physical Therapy Relative rest no dancing, cutting or jumping 1
Evidence for Conservative Treatment Options for Patellar Instability Immobilization none Aspiration none Ice - minimal Pharmacotherapy - none Orthoses/ Taping none Exercise Therapy Yes but what exactly? Electrical Stimulation none Liu et al. Patellar Instability Management: A Survey of the International Patellofemoral Study Group. AJSM. 2017 Oct 1:363546517732045. 34-question, case-based online survey Non-operative management is the current standard of care for a first-time dislocation in the absence of an osteochondral fragment or loose body requiring excision (100% agreement) Longo et al. Treatment of Primary Acute Patellar Dislocation: Systematic Review and Quantitative Synthesis of the Literature. CJSM. 2017 Nov;27(6):511-523. 2134 knees (2086 patients) included, average age at dislocation 20 years The average Kujula score (AKPS) was 76 for patients treated conservatively and 89 for patients treated surgically with short-term F/U (<5 years) The average Kujula score was 88 for patients treated conservatively and 87 for patients treated surgically with long-term F/U (>5 years) The rate of recurrence was lower in the surgical group (25%) than in the conservative group (36%) The complication rate was 7% (29 of 441 knees) in the surgical group No complications were reported for patients treated conservatively 2
Saccomanno et al. Surgical versus conservative treatment of primary patellar dislocation. A systematic review and metaanalysis. Int Orthop. 2016 Nov;40(11):2277-2287. 9 studies were included in the meta-analyses. Methodological quality of the studies was moderate to low. Surgical treatment showed: reduced re-dislocation rate (RR = 0.62; 95% CI = 0.39, 0.98, p = 0.04) better results on Hughston VAS score (SMD = -0.32; 95% CI = -0.61, -0.03; p = 0.03) better results with running (OR = -0.52; 95% CI = 0.31, 0.88; p = 0.01). Conservative treatment showed: less occurrence of minor complications (OR = 3.46; 95% CI = 2.08, 5.77; p = 0.01) better results in the figure-of-8 run test (SMD = 0.42; 95% CI = 0.06, 0.77; p = 0.02) better results in the squat down test (SMD = -0.45; 95% CI = -0.81, -0.10; p < 0.00001). No other significant differences could be found. Vavken et al. Treating patella instability in skeletally immature patients. Arthroscopy. 2013 Aug;29(8):1410-22. 20 articles - 456 knees in 425 patients (131 male patients, 294 female patients) followed-up for 57 ± 42 months on average were included in the analysis. 2 studies focused specifically on conservative versus surgical treatment in acute dislocations and reported no difference in outcomes after 7 and 14 years, even in the face of slight trochlear dysplasia For recurrent instability, consistent beneficial effects from surgical stabilization were found on clinical scores, postoperative stability, and radiographic assessment There is no evidence for growth disturbance with surgical patellar stabilization in immature patients Nwachukwu et al. Surgical versus conservative management of acute patellar dislocation in children and adolescents: a systematic review. KSSTA. 2016 Mar;24(3):760-7. 470 conservatively treated/ 157 operatively treated knees Conservatively treated patients (avg. 17 yo/ mean F/U 4 yrs) Surgically managed patients (avg. 16 yo/ mean F/U 5 yrs) Conservatively managed knees had a 31% rate of recurrent dislocation rate compared to 22% in surgical knees (p = 0.04) Trochlear dysplasia and skeletal immaturity confer greater risk for recurrent instability Surgical treatment may provide clinically important quality of life and sporting benefit 3
Lewallen et al. Predictors of recurrent instability after acute patellofemoral dislocation in pediatric and adolescent patients. AJSM. 2013 Mar;41(3):575-81. 222 knees (120 male/ 102 female) 210 pts.; avg. 15 yo (range, 9-18 yo) 24 patients (11%) underwent early surgery All others were initially treated non-operatively 198 patients - 76 (38%) had recurrent instability, and 39 (51%) required surgery Recurrent instability was associated with trochlear dysplasia (P <.01) Patients with both immature physes and trochlear dysplasia had a recurrence rate of 69% (33/48), with a hazard ratio of 3.3 Age, sex, body mass index, and patella alta were not statistically associated with recurrent instability. Smith et al. Clinical outcomes of rehabilitation for patients following lateral patellar dislocation: a systematic review. PT. 2010 Dec;96(4):269-81. 29 publications included Although a proportion of patients experienced recurrent instability episodes, a large proportion of patients reported acceptable outcomes following PT No randomized controlled clinical trials were identified assessing different PT interventions The evidence base included a number of underpowered studies which poorly described the specific PT interventions Physical modalities Physical and instrumental therapies are commonly used in the various phases of the treatment of patients who sustained a first episode of patellar dislocation Clinical efficacy has never been demonstrated in prospective or retrospective studies, the most correct way in which they should be used is unclear Cryotherapy is useful in the first 48 hours of injury, but it can be used also in the following 3 4 weeks to address the joint effusion and the pain after therapy Electrostimulation can prevent muscle atrophy, promote muscle strengthening, and facilitate functionally useful movements Level of recommendation: D Key points: At present, there is no clinical evidence on what physical modalities to use in the management of patients following their first episode of patellar dislocation Vetrano et al. I.S.Mu.L.T. first-time patellar dislocation guidelines. Muscles Ligaments Tendons J. 2017 Jan-Mar; 7(1): 1 10. 4
Taping, bracing and casting Taping is used after the first 6 weeks to reduce pain, facilitate the recruitment of the VMO, and help psychologically Casting has been advocated to allow healing of the medial retinaculum and of the MPFL, but prolonged immobilization has adverse effects on ligament, bone, cartilage and muscles. The use of braces or tapes could offer faster functional recovery, but potential for longer time for MPFL healing? Level of recommendation: D Key points: There is no evidence regarding the choice between the taping, bracing or complete immobilization in the management of patients with patellar dislocation Taping seems to help with symptoms, but has no effect on the patellar realignment Prolonged immobilization has negative effects Vetrano et al. I.S.Mu.L.T. first-time patellar dislocation guidelines. Muscles Ligaments Tendons J. 2017 Jan- Mar; 7(1): 1 10. Summary Conservative management for 1st time patellar dislocations is a reasonable approach in most circumstances PT is recommended Further research is needed on what PT should be included and what other modalities are also indicated Thanks! 5
1/30/2018 Patellar Instability: Alignment and Rotation Dr. Nirav K. Pandya Assistant Clinical Professor of Orthopedic Surgery University of California San Francisco Director, Pediatric Sports Medicine Nirav.Pandya@ucsf.edu @DrNiravPandya Disclosures Consultant: Orthopediatrics Case Presentation #1 13 year old female with cc: recurrent patellar instability Initial traumatic event and several since then Underwent MPFL repair / imbrication at outside hospital Continues to have patellar instability / subluxations 1
1/30/2018 Case Presentation #1 Why Did This Fail???? What We Concentrate On Bone Before Soft Tissue! Rotation Alignment 2
1/30/2018 Forgotten Factors & Factors for Failure 1. Tunnel placement 2. Femoral anteversion 3. Patella alta 4. Increased TT-TG 5. Patellar tilt 6. Trochlear dysplasia 7. Genu valgum Rotation: Clin. and Radiographic 1. Excessive femoral anteversion - Especially unilateral - Trochlea is offset from the patella - Generally 20 degrees and above Rotation: Clin. and Radiographic 3
1/30/2018 Rotation: Clin. and Radiographic Clinical Exam: Case Presentation #1 - Hip IR 75 / 45; Hip ER 55 / ER 55 MRI Torsional Profile: - Femoral Anteversion = 47 degrees on R / 7 degrees on L Treatment: Rotational Osteotomy 4
1/30/2018 Treatment: Rotational Osteotomy 5 cm Treatment: Rotational Osteotomy Correct to equal other side or normalize Alignment: Clin. and Radiographic 2. Genu Valgum - 10 degrees and higher - IM distance > 8 cm - Lateral force to patella 5
1/30/2018 Alignment: Clin. and Radiographic Treatment: Guided Growth (Immature) Case #2: 12 year old with genu valgum of 20 degrees and patellar instability Treatment: Osteotomy (Mature) Case #3: 16 year old with genu valgum of 18 degrees and patellar instability 6
1/30/2018 Treatment: Osteotomy (Mature) 1 mm wedge per degree of correction Treatment: Osteotomy (Mature) Treatment: Osteotomy -Correct Alignment and Rotation Case #4: 20 year old with genu valgum and femoral anteversion of 45 degrees with patellar instability 7
1/30/2018 Treatment: Osteotomy (Mature) Correct valgus deformity and then rotate distal fragment to correct rotation Take Home Points 1. Always assess bony deformity before soft tissue 2. Look at alignment and rotation as reasons for patellar instability in isolation or in combination 3. Guided growth, rotational / alignment osteotomies are your friend Thank You 8
Surgical Treatment of Patellar Instability Options for MPFL Reconstruction Stephanie W. Mayer, MD University of Colorado Sports Medicine Children s Hospital Colorado Disclosures Arthrex Consultant Patellar Instability Incidence : 23.2 per 100,000 Highest among adolescents aged 14 to 18 years - 147.7 per 100,000 Mean age at dislocation 21.4 ± 9.9 years 54.4% female Sanders Sports Health 2017 1
Patellar Instability Complex problem Age Sex Ligamentous laxity Limb alignment: rotation, angular Trochlear dysplasia Patellar height TTTG Dynamic forces Core, glutes, VMO Medial Knee Anatomy Midpoint of insertion on patella was 41.4% the length from top Midpoint of insertion on femur was between adductor tubercle and medial epicondyle/superficial MCL VMO fibers attach to proximal aspect LaPrade JBJS 2007 Indications for MPFL Reconstruction Recurrent Instability Patellar Dislocation with chondral surgery First time dislocation with risk factors for recurrence? Up to 88% recurrence rate with multiple risk factors Patella alta, trochlear dysplasia, adolescent 2
Indications for MPFL Reconstruction Instability which caused an operative chondral injury Recurrent Instability Surgical Considerations in MPFL Intervention Repair/Imbrication vs Reconstruction Graft Choice Fixation Method Skeletal Immaturity Concomitant Procedures MPFL Repair/Imbrication Direct anatomic repair of MPFL from either the patellar or femoral insertions Imbrication involving tightening of the stretched ligament Ahmad AJSM 2000 3
MPFL Repair/Imbrication Eight cases of ACUTE repair of femoral sided injury 86% return to activity level, 97% satisfaction One patient had recurrent subluxations, no dislocations No difference in recurrence rates or satisfaction between MPFL repair and non-operative treatment of CHRONIC recurrent patellar instability MPFL Repair/Imbrication Algorithmic approach to repair or reconstruction in CHRONIC recurrent patellar instability 1 recurrence in repair group, 0 in reconstruction group This patient had a high TTTG but refused TTO Small cohort but a promising algorithm MPFL Repair/Imbrication 4
MPFL Repair/Imbrication Patellar Sided Repair Incision at medial border of patella Dissection down to space between layer 2 and 3 Identify stump of MPFL and VMO insertion Secure to patella anatomically Variety of fixation methods Imbrication pants over vest to advance ligament/retinaculum over patella; VMO advanced over ligament Patellar Side MPFL Tissue MPFL Repair/Imbrication Femoral Sided Repair Incision just anterior to adductor tubercle Identify saphenous nerve branches Identify adductor tendon, VMO, MPFL stump Anatomic repair of MPFL and VMO Variety of fixation methods Imbrication shorten MPFL to tighten; advance VMO over MPFL repair Christiansen Arthroscopy 2008 Surgical Considerations in MPFL Intervention Repair/Imbrication vs Reconstruction Graft Choice Fixation Method Skeletal Immaturity Concomitant Procedures 5
Weeks et al MPFL Reconstruction Graft Choices Hamstring Autograft Semi-T or Gracilis Allograft Quad Tendon Turndown Synthetic Graft Options 6
MPFL Reconstruction No statistical difference in graft choice outcomes Overall recurrence rate 1.8 4.77% 10% in adolescents Surgical Considerations in MPFL Intervention Repair/Imbrication vs Reconstruction Graft Choice Fixation Method Skeletal Immaturity Concomitant Procedures MPFL Reconstruction Various Fixation Methods on Patella and Femur Interference Screws Cortical Suspensory Fixation Suture Anchors Generally ~6mm graft Harvest 25cm, need about 20cm (or less) if doubled 7
MPFL Reconstruction Suspensory cortical fixation on femur and patella and interference screw fixation on femur demonstrated superior strength to native MPFL Mean strength of suture anchor fixation on patella did not, but results were inconsistent Suture anchor patella group had lower mean failure load 201N than interference screw group 299N The most common mode of failure in the suture anchor and suspensory fixation groups - graft-suture interface, in the interference screw group - tendon graft pulling out of the tunnel MPFL Reconstruction Fixation on Patella Center of MPFL is approximately 1/3 the distance from proximal to distal Drill tunnels Interference fixation Cortical suspensory fixation Suture anchors MPFL Reconstruction Fixation on Femur Schottle et al 2007 1mm anterior to posterior cortex In between line across Blumensats and medial condyle Kruckeberg et al 2018 Between adductor tubercle and medial epicondyle Do these correlate??? 8
MPFL Reconstruction - Radiographic Landmarks MPFL Reconstruction - Isometry MPFL is isometric through range of motion from ~20-60 Elevated TTTG and patella alta can limit the isometry Schottles point may not be isometric in this situation In extension MPFL is tighter than usual In flexion MPFL is looser than usual MPFL Reconstruction Quadriceps tendon turndown Medial 8-10 cm of quad Turned 45 degrees down to anatomic point on femur Fixation with soft tissue alone in skeletally immature Fixation with soft tissue or interference if mature 9
MPFL Reconstruction Medial Patello-Tibial Ligament Reconstruction Multiple techniques utilized Some in combination with MPFL <10% recurrence rate overall MPFL Insertion and the Physis The center of the MPFL is (usually) distal to the physis in young children Becomes at level of physis more consistently at age 10-11 20 deg anterior and distal shown to be safe drilling path below physis MPFL Reconstruction Complications Graft rupture Patella fracture Arthrofibrosis Stiffness due to graft placement Patellar overload and pain/oa 10
MPFL Reconstruction Complications Patella fracture Lower risk with more posterior tunnels Error is generally to go too anterior for fear of articular cartilage True MPFL anatomy is just anterior to articular cartilage border medially MPFL Reconstruction Complications Importance of graft placement and tensioning Too proximal femoral tunnel, tight in flexion and increases pressure Too distal, tight in extension and increased pressure 2N may be the optimal graft tension MPFL Reconstruction Complications One quadrant lateral translation Allowing 5-10mm lateral translation at 30 deg restrained patella adequately but did not over-constrain the knee Allowing 0mm lateral translation increased medial pressures by 57% 11
Concomitant Procedures Lateral Release TTO Trochleoplasty Cartilage restoration Long limb alignment correction Rotational alignment correction THANK YOU Discussion and Questions? 12
2/6/2018 VuMedi Webinar Nonoperative and Surgical Management Strategies for Patellofemoral Instability Chondral Injuries Curtis VandenBerg, MD Director Sports Medicine Program Children s Hospital Los Angeles Assistant Professor of Orthopaedic Surgery, USC Keck School of Medicine I have not had a personal financial relationship in the last 12 months with the manufacturer of the products or services that will be discussed in this CME activity DECLARATION I attest that I will comply with ACCME Standards for Commercial Support of Continuing Medical Education to ensure that this CME activity is free of commercial bias or the appearance thereof. I will base all clinical recommendations on evidence that is accepted within the profession of medicine as adequate justification in the care of patients. All scientific research referred to in support of a patient care recommendation will conform to generally accepted standards of experimental design, data collection, and analysis. AGENDA Epidemiology Anatomy Clinical Presentation Evaluation and Imaging Injury patterns (medial pat, LFC) Rotational/Angular profile; TT-TG/TT-PCL; troch dysplasia Case Examples Surgical Treatment Options Primary repair osteochondral, chondral only, screw, suture Marrow Stimulation Cellular based treatments DeNovo PJAC, ACI, biocartilage, PACI Osteochondral transfer OATS or allograft Combined MPFLR/lateral lengthening Role of AMZ Impact of trochlear dysplasia Outcomes Future Directions 1
2/6/2018 Imaging Xrays: AP, lateral, notch, sunrise MRI: arthrogram can enhance cartilage visualization Rarely CT Pinkowsky et al, Sports Med Arth Rev, 2016. Osteochondral Fracture after Patella Dislocation Xray and Arthroscopy: 52% (Hawkins, AJSM, 1986) MRI: 58% (Kirsch, AJR, 1993) MRI: 76% (Virolainen, Radiology, 1993) <16 years old: 39% (Nietosaara, JPO, 1994) Rate of Chondral Injury with Patellar Disloction 39 patients 1 st time patella dislocation Arthroscopy Can be difficult to assess on Radiographs and MRI 95% rate of chondral injury 100% on patella OCF: inferomedial facet Cracks: central dome 31% on lateral femoral condyle Nomura et al, Arthroscopy, 2003. 2
2/6/2018 Anatomy Cartilage restoration techniques with unpredictable results Unique cartilage thickness and contour of the patella Higher density of subchondral bone (nearly completely cortical) High dynamic shear and compressive forces at trochlear articulation Exposure difficulties Grawe et al, Cartilage, 2017. Treatment Acuity Damage to Osteochondral Fragment Defect size Grawe et al, Cartilage, 2017. Patellofemoral Chondral Injury Treatment Observation Chondroplasty Microfracture Fixation Cellular DeNovo NT (Zimmer Biomet; Particulated allograft juvenile cartilage) ACI Biocartilage Particulated AUTOLOGOUS chondrocyte implantation? Osteochondral autograft/allograft Grawe et al, Cartilage, 2017. 3
2/6/2018 Patellofemoral Instability Management Risk factors for patellar dislocation Patella alta Trochlear dysplasia High Q angle angular profile; femoral and tibial axial plane Lateral retinaculum MPFL Non-modifiable risk factors Connective tissue laxity Family history Metzler et al, Orthopedics, 2015. Osteochondral Fracture Repair Preferred treatment Intact or swollen cartilage Bone attached vs. Chondral only Acute? Timing? Compression fixation bioabsorbable Non-resorbable hardware removal Photos Courtesy Brant Sachleben, MD Arkansas Children s Hospital Osteochondral Fracture Repair Other repair strategies Crossing Sutures Sutures tied on anterior surface of patella Ng et al, Arth Tech, 2017. 4
2/6/2018 Stabilization Chondroplasty <1cm 2, partial thickness May be asymptomatic Microfracture Small, full-thickness lesion (1cm 2 ) Unfavorable outcomes weight bearing areas of patella and 1-4cm 2 Short term improvement: first 24 months Long term outcomes unclear Limited hyaline repair tissue Variable repair cartilage volume Possible functional deterioration Mithoefer et al, AJSM, 2009. Cellular Treatments Cellular DeNovo NT (Zimmer Biomet; Particulated allograft juvenile cartilage) ACI Biocartilage Particulated AUTOLOGOUS chondrocyte implantation? 5
2/6/2018 Cellular Particulated Juvenile Allograft Cartilage 27 patients full thickness PF chondral lesion treated with PJAC 3.84yr f/u Improved outcomes IKDC 45.9 vs 71.2, P <.001 No reoperation for graft-related issues 67% lesion filling on T2 maping MRI Persistent morphologic differences b/t graft site and adjacent cartilage Wang et al, Arthroscopy, 2018. Cellular ACI 92 patients patella or trochlear chondral lesions 12.6 year f/u Lysholm 61 70 72% better or unchanged 93% would undergo operation again No kissing lesion = better prognosis Vasiliadis et al, KSSTA, 2011. Cellular Particulated AUTOLOGOUS Chondrocyte Implantation Courtesy Bert Mandelbaum, MD and Natasha Trentaosta, MD; Santa Monica, CA 6
2/6/2018 Osteochondral Allograft >4cm 2 defects Matched cadaver Failed prior cartilage repair technique Gracitelli et al, AJSM, 2015. Osteochondral Allograft 28 knees isolated patella OCA Mean age = 33.7yo 60.7% required further surgery 28.6% OCA failures OCA survivorship 78.1% at 5 and 10 years 55.8% at 15 years Gracitelli et al, AJSM, 2015. 7
2/6/2018 Thank You 8