Knee Injuries Anatomy and Physiology 101 for Attorneys Phil Davidson, MD Heiden-Davidson Orthopedics Salt Lake City, UT May 2011
Introduction Dr. Phil Davidson Park City and SLC clinics Education: Harvard, Cornell, Baylor, Kerlan-Jobe Clinic Surgical Specialist in Cartilage Restoration & Joint Resurfacing Knee and Shoulder Injuries Affiliated NFL, MLB, PGA, FDA
Outline Introduction to the Knee Types of Injuries Meniscal Cartilage Ligament Treatment Options What to Look for in Medical Records and Diagnostic Tests Acute- Chronic Exacerbation Questions and Answers
Knee Anatomy 101 Distal Femur Proximal Tibia Patella 4 Ligaments 2 Menisci Chondral (articular) surfaces
Surgical views of the knee
Meniscal Injuries
Meniscal Injuries Very common, subject to injury AND degeneration Acute Injuries vs. Chronic Tears Most common indication for arthroscopic surgery Most common orthopedic surgery in the US Chronic injuries with acute exacerbations How do you tell the difference Can occur with MVA twist or dashboard injury
Diagnosis History Physical Findings Meniscal Injuries Tenderness- along joint line Effusion (swelling) McMurray s (lateral) Pain with Hyperflexion or hyperextension Radiographs MRI is most sensitive no contrast needed Xrays do not show soft tissues
Meniscal Injuries Mechanisms Twisting Slip and Fall USUALLY NOT DIRECT BLOW Symptoms Pain Swelling Catching Locking Give out
Treatment- Meniscal Injury Not all positive MRI s require surgery Symptomatic treatment NSAIDS/Cortisone injections- inflammation only Physical therapy very limited, appx 10 visits or 1 month max Meniscus little or no capacity to heal
Arthroscopic Surgery Partial Meniscectomy Debridement Easy recovery Vast majority of tears Meniscal Repair Vascular Zone Acute, clean tears 1/3 don t heal Meniscal Injuries
Meniscal Injuries Recovery Period Meniscectomy (clean up) Immediate walking, bending Return to transitional duties 7-10 days Little PT or Rehab Full duties at 3-6 weeks Meniscal Repair (Rare ie. Less than 10%) Brace/crutches for 4-6 weeks PT 2-3x/week 4-8 wks Seated duty at work appx 8 wks Full duties appx 12 weeks
Chondral (Cartilage) Injuries Articular Cartilage Damage Smooth, shiny cartilage on ends of bone Damage or loss can lead to early arthritis Produce loose bodies
Cartilage Different types Articular cartilage Meniscal cartilage Many different in body Joint surface Articular cartilage Tidemark region Subchondral bone Analogy, tire tread
Articular Cartilage Grading Grade 1 Grade 2 Grade 3 Grade 3 Grade 4
Multiple Etiologies Yield Grade IV (full thickness) Lesions Trauma Focal degeneration Instability associated with injury
Weight Bearing Articular Cartilage Defects Pain, Clicking, Catching Loose pieces Progressive problem Limits activities Can be result of injury or gradual problem Cartilage has NO healing capacity!!!
Cartilage Restoration & Joint Resurfacing A wide realm between.. Arthroscopic debridement
Spectrum of Pathology Spectrum of Treatments.solution lies in understanding comprehensive pathology and full realm of treatments
Treatment Options for Symptomatic Cartilage +/- Bone Defects Based on Size Small < 1 cm 2 Debridement MST Mosaicplasty Medium 1 4 cm 2 Debridement MST Scaffolds Mosaicplasty OCA Chondrocytes +/- scaffolds Inlay Prosthesis Large >4 cm 2 OCA Chondrocytes +/- scaffold Onlay Prosthesis Total Joint
Demand Expectations Job Age Activities Complicity Biological, not just chronological Comorbidities BMI Diabetes Smoking Medical Illness
Cartilage Restoration/Joint Resurfacing Treatments: an evolving continuum of options Marrow stimulation Biological restoration Mosaicplasty / OATS OCA Chondral Auto and Allografts Bio-synthetics/scaffolds Modulated therapy Cellular therapy Joint Resurfacing Polymeric/Hydrogels Inlay Arthroplasty Micro-invasive prostheses Digitally custom onlay Total Joint
Biological Options Autologous Chondrocytes ACI MACI Osteochondral Grafts Autogenous Allogeneic Chondral grafts Biologically Active Scaffolds
Illustrative Case 22 yr old semi truck driver Jackknife MVA
Orthobiologic scaffold Off the shelf alternative theoretically better than microfracture Less morbidity than mosaicplasty Fill donor sites mosaicplasty No allograft donor issues Smaller type defects < appx 2cm
Post Op MRI 17 mos
Rehabilitation Protected weight bearing 6 weeks Med + Lat FC Full WB PF Early full motion CPM when possible Return to light work- 6-12 weeks MMI appx 4-5 mos
Osteochondral Grafts - Auto vs. Allo Autograft (OATS) No donor needed Limited availability Small lesions only Repair OCD Allograft (OCA) Very effective Young patients Handle Bone loss Larger lesions Generally > 2 cm²
OCA (osteochondral allograft) Procedure
OCA - Procedure
OCA - Procedure
OCA - Procedure
OCA - Procedure
OCA - Procedure
OCA - Procedure
OCA - Procedure
OCA - Procedure
What if biologics will not or cannot work?...next step beyond biologic Inlay Prostheses
A new paradigm for joint resurfacing Geometry based on patient s native anatomy Intraoperative joint mapping Account for complex asymmetrical geometry Extension of biological resurfacing
Knee Inlay Implants HemiCAP small unipolar knee UniCAP Medial and Lateral Includes Tibial Inlay PF HemiCAP Regular & XLT wave
Inlay resurfacing medial knee 46 year old construction worker, injured at work
Inlay medial knee resurfacing
UniCAP medial knee resurfacing
UniCAP medial knee resurfacing
UniCAP medial knee resurfacing
UniCAP medial knee resurfacing
50 year old day care worker fell taking care of children
Combining Biologics with Inlay Arthroplasty 29 year old firefighter
6 wks post op back at work light duty 12 wks post op full RTW as firefighter
More extensive than Inlay Very little bone resection Implants custom made from CT scan Onlay Resurfacing beyond inlay
42 year old FedEx Driver
Onlay Resurfacing Outpatient or one night stay Full WB immediately RTW Light duty 6 weeks Full duty appx 12 weeks
Ligament Injuries
Ligament Injuries ACL Anterior Cruciate Ligament PCL Posterior Cruciate Ligament MCL Medial Collateral Ligament LCL Lateral Collateral Ligament
Ligament Injuries MCL Inner part of the knee Most common ligament injury Tenderness medially Laxity medially Most commonly treated conservatively in a brace 4-6 weeks, physical therapy for ROM, modalities
Ligament Injuries Posterior Cruciate Ligament Prevents posterior translation of tibia on femur Most commonly occurs from direct blow to anterior tibia, fall onto knee or dashboard injury Isolated injuries potentially treated conservatively Physical therapy for ROM, strengthening Arthroscopic assisted reconstruction
Ligament Injuries PCL Tear on MRI
Ligament Injuries ACL Prevents anterior translation of tibia on femur Most common surgical treated ligament rupture Twisting, noncontact, slip and fall Most common complaint is instability
ACL Tear ACL Graft
Torn Ligament (ACL seen here)
Bone Tendon Bone Autograft ACL Reconstruction- Replace not Repair Patellar Tendon Graft Diminishing popularitypost op pain! Hamstring Tendon- Autograft Allograft Donor Tissue Not all tissue is the same
ACL Protects mensicus from shear injury Surgical Recovery 3-12 wks RTW 5-6 mos full activities Ligament Injuries
PRP- platelet rich plasma Supercharged healing Concentrate healing elements from own blood Growth factors Can create variety of forms, liquid, gel, membrane to facilitate biologic healing of surgical repairs ACL reconstruction, Meniscal repair, Rotator Cuff Repair
Biological ACL Surgery Graft, incorporates allograft, autograft and PRP Allograft gives large amount of collagen Autograft, gracilis Promotes healing Very small, not missed
Fractures about the Knee Tibial plateau fractures Falls from height, MVAs Patellar fractures Slip and fall Direct blow Both involve articular cartilage Joint congruency is the goal
Fractures about the Knee Diagnosis History Physical exam Radiology Plain fims MRI for associated injuries CT scan for complex fractures Primarily plateau fracture
Fractures about the Knee Operative vs. nonoperative 2mm guideline Surgery Patella fractures Open procedure Screws and wires Physical therapy and recovery 8-12 weeks
Fractures about the Knee Operative vs. nonoperative 2mm guideline Surgery Patella fractures Open procedure Screws and wires Physical therapy and recovery 8-12 weeks
Medical Records Review History Injury report, ER visit, Occ Med visit, Ortho visit, OP NOTE, follow ups, MRI reports, PT notes, DC notes OP NOTE What is said acuity, degeneration, technique What is NOT said (joint observations) Imaging MRI, MR Arthrogram (contrast), plain films IME s (Author, requesting party, findings) Rating letters and correspondence Return to work and permanent restrictions
Acute, Chronic, Recurrent, Aggravation Evaluation and imaging techniques to determine acuity vs. chronicity of an injury Energy/Injury Equation Detailed history Understanding the mechanism of injury Common causes of common injuries Biomechanical forces in injuries Does it add up?????
Imaging Techniques Plain X ray Standard views needed Can show Degenerative pre-existant findings Can show DJD over time Soft tissues not seen MRI Soft tissues- Ligaments, Meniscus, Cartilage Can show bleeding and acuity
How to decide chronicity Credibility of patient, reliability of story Are they believable? Reported history What happened? When? How? Witnessed? Mechanism of injury Does it make sense? Physical Findings Does it match mechanism? Is it acute? Imaging Findings Identify objective data
Did this happen when and how the patient said it happened? Meniscal Tear, Ligament Tear, Cartilage Injury Mechanism of injury Physical exam Plain Xray Diagnostic injections MRI imaging Acuity
Physician Conclusions medical- legal evaluations Physician needs to evaluate data and decide upon causal relationship This includes notion of apportionment Is the physician credible? Was valid data available to form opinion? Assigning and allocating disability Assigning and projecting further care and costs
Thank You now accepting new WC and Legal patients offices: Park City and SLC (Holladay) phildavidsonmd@gmail.com 435-615-8822 www.phildavidsonmd.com www.heidendavidsonortho.com