Knee Pain & Acute Trauma Diagnosis Imaging Part II | El Paso, TX

Share

Meniscal Tears

 

  • Acute or chronic. Imaged with MRI (95% sensitivity & 81% specificity)
  • Menisci are formed by a composition of radial and circumferential collagen fibers (97% type 1) mixed with cartilage, proteoglycans, etc. 65-75% H2O
  • Aging can lead to meniscal attrition
  • Acute tears are d/t rotational and compressive forces, ACL deficient knees show greater chances of meniscal tears
  • Posterior horn of medial meniscus is m/c torn except in acute ACL tears when the lateral meniscus is m/c torn
  • The meniscus is well vascularized in children. In adults, 3-zones exist: inner, middle and outer (above bottom image)
  • Injury of the inner zone has no chance of healing
  • Injury of the outer zone (25% in total) has some healing/repair

Clinical Presentation

  • Pain, locking, swelling
  • Most sensitive physical sign: pain on palpation at the joint line
  • Tests: McMurry, Thessaly, Apply compression in prone
  • Management: conservative vs. operative depends on location, stability, patient’s age, and DJD and the type of tear
  • Partial meniscectomy is performed. 80% proper functions on follow up. Less favorable if >40-y.o and DJD
  • Total meniscectomy is not performed and only viewed historically. 70% OA 3-years after surgery 100% OA after 20 years post surgery.

Axial MR

 

  • Appearance the medial (blue) and the lateral meniscus (red)

Menisci Play Significant Role

 

Types Location & Stability

 

  • Types, location, and stability of tears are v. important during MRI Dx
  • Vertical/longitudinal tears especially occur in acute ACL tears. Some longitudinal tears found at the periphery or “red zone” may heal
  • Bucket handle tear: longitudinal tear in the inner edge that is deep and vertical extending through the long axis and may displace into a notch
  • Oblique/flap/parrot-beak are complex tears
  • Radial tear at 90-degree to plateau

Axial T2

 

  • Axial T2 WI fat-sat and coronal STIR slices of the posterior horn of the medial meniscus.
  • Note a radial tear of the posterior horn of the medial meniscus near the meniscal root. This is potentially an unstable lesion requiring operative care
  • The meniscus, in this case, is unable to provide a “hoop-stress mechanism.”

MRI Slices Coronal & Sagittal

 

  • Fat-sat coronal and sagittal proton density MRI slices revealing horizontal (cleavage) tear that is more typical in the aged meniscus
  • In some cases, when this tear does not contain a radial component, it may partially heal obviating the need for operative care

T2 w GRE Sagittal MRI Slice

 

  • Complex tear with a horizontal oblique and radial component.
  • This type of tear is very unstable and in most cases may need operative care

Bucket Handle Tear

 

  • Bucket handle tear are m/c in the medial meniscus esp. with acute ACL and MCL tear
  • MRI signs; double PCL sign on sagittal slices
  • Absent “bow-tie” sign and others
  • Most cases require operative care

DDx From Meniscal Degeneration

 

  • Occasionally meniscal tears need to be DDx from meniscal degeneration which may also appear bright (high signal) on fluid-sensitive MRI
  • The simplest rule is that if there is a true meniscal tear aka Grade 3 lesion, it always reaches/extends to the tibial plateau surface

The Role of MSK Ultrasound (US) in Knee Examination

  • MSK US of the knee permits high resolution and dynamic imaging of primarily superficial anatomy (tendons, bursae, capsular ligaments)
  • MSK US cannot adequately evaluate cruciate ligaments and the menisci in their entirety
  • Thus MR imaging remains modality of choice

Potential Pathologies Successfully Evaluated by MSK US

  • Patellar tendionosis/patellar tendon rupture
  • Quadriceps tendon tear
  • Prepatellar bursitis
  • Infrapatellar bursitis
  • Pes Anserine bursitis
  • Popliteal cyst (Baker cyst)
  • Inflammation/joint effusion with synovial thickening and hyperemia can be imaged with US (e.g., RA) especially with the addition of color power Doppler

Patient Presented With Atraumatic Knee Pain & Swelling

 

  • Radiography revealed sizeable soft tissue density within the superficial pre-patella region along with mild-to-moderate OA
  • MSK US demonstrated large septated heterogeneous fluid collection with mild positive Doppler activity on the periphery indicating inflammation d/t Dx of Superficial pre-patella bursitis

Long Axis US Images

 

  • Note normal lateral meniscus and fibers of LCL (above bottom image) compared to
  • Horizontal degenerative cleavage tear along with protrusion of lateral meniscus and LCL bulging (above top image)
  • Major limitation: unable to visualize the entire meniscus and the ACL/PCL
  • MRI referral is suggested

Rupture of Distal Tendon of Quadriceps

 

  • Note rupture of distal tendon of the Quadriceps muscle presented as fiber separation and fluid (hypo to anechoic) fluid collection within the substance of the tendon
  • Advantages of MSK US over MRI to evaluate superficial structures:
  • Dynamic imaging
  • Availability
  • Cost-effective
  • Patient’s preparation
  • Disadvantages: limited depth of structures, inability to evaluated bone and cartilage, etc.

Osteochondral Knee Injuries (OI)

  • osteochondral knee injuries can occur in children 10-15 y.o presented as Osteochondritis Dissecance (OCD) and in mature skeleton m/c following hyperextension and rotation trauma, particularly in ACL tear.
  • OCD-typically develops from repeated forces in immature bone and affects m/c postero-lateral portion of the medial femoral condyle.
  • OI in mature bone occurs m/c during ACL tears mainly affecting so-called terminal sulcus of the lateral femoral condyle at the junction of the weight-bearing portion opposed to tibial plateau and the part articulating with the patella
  • Osteochondral injuries may potentially damage the articular cartilage causing secondary OA. Thus need to be evaluated surgically
  • Imaging plays an important role and should begin with radiography often followed by MR imaging and orthopedic referral.

OCD Knee

 

  • 95% associated with some trauma. Other etiology: ischemic bone necrosis especially in adults
  • Other common location for osteochondral injuries: elbow (capitellum), talus
  • 1st step: radiography may detect osteochondral fragment potentially attached or detached
  • Location: a posterior-lateral aspect of the medial femoral condyle. Tunnel (intercondylar notch) view is crucial
  • MRI: modality of choice >90% specificity and sensitivity. Crucial for further management. T1-low signal demarcating line with T2 high signal demarcating line that signifies detachment and unlikely healing. Refer to orthopedic surgeon
  • Management: stable lesion esp. in younger children>off weight-bearing-heals in 50-75%
  • Unstable lesion and older child or impending physeal closure>operative fixation.

 

Knee Trauma

 

Dr. Alex Jimenez D.C.,C.C.S.T

Welcome-Bienvenido's to our blog. We focus on treating severe spinal disabilities and injuries. We also treat Sciatica, Neck and Back Pain, Whiplash, Headaches, Knee Injuries, Sport Injuries,�Dizziness, Poor Sleep, Arthritis. We use advanced proven therapies focused on optimal mobility, health, fitness, and structural conditioning. We use Individualized Diet Plans, Specialized Chiropractic Techniques, Mobility-Agility Training, Adapted Cross-Fit Protocols and the "PUSH System" to treat patients suffering from various injuries and health problems. If you would like to learn more about a Doctor of Chiropractic who uses advanced progressive techniques to facilitate complete physical health, please connect with me. We a focus on simplicity to help restore mobility and recovery. I'd love to see you. Connect!

Recent Posts

The Body’s Joints and Protection From Rheumatoid Arthritis

Rheumatoid arthritis is said to affect around 1.5 million individuals. Recognized as an autoimmune condition… Read More

Chiropractic Treatment or Physical Therapy: What Are My Options?

Chiropractic treatment and physical therapy are treatment methods/approaches that are conservative, non-invasive, and are both… Read More

The Benefits of Regular Chiropractic Spinal Adjustments

Individuals tend to think of chiropractic treatment for pain relief, injury recovery, and help with… Read More

Diabetic Back Pain: Ways To Bring Relief

The diabetic disease processes can be a contributor to chronic back pain. Diabetes can damage… Read More

Pelvic Pain and Chiropractic Relief

The pelvis is designed to bear and distribute the weight of the body along with… Read More

Online History & Registration 🔘
Call us Today 🔘