Question 1

Patella Wiberg Classification

Accepted Answer

The Wiberg Scale is used to describe the shape and size of the medial and lateral facets of a patella. The shape of any patella's facets can be described in one of three ways:

Concave: Having a surface that curves inward, like the interior of a circle or sphere.
Convex: Having a surface that curves outward, like the exterior of a circle or sphere.
Flat: A level, even surface absent of curvature.

IMPORTANT: When determining where on the Wiberg scale a patella belongs, the facet curvatures must be overserved by viewing the patella from the base (or opposite the apex). This principal also applies when photographing the grafts for dissection sheets, therefore the apex of the patella should be placed down onto the photo block, or base-side up toward the camera.

Type I:

Both the medial and lateral facets are concave, and roughly of equal size and shape.

Left Patella, Type I

Type II:

The medial facet is mostly flat, or only slightly convex.
The lateral facet is concave.
The lateral facet is slightly larger than the medial facet.

Left Patella, Type II

![Left Patella, Type II](https://storage.crisp.chat/users/helpdesk/website/45175be43c538400/type-ii-2_tpgb

Question 2

Left/Right Graft Designation: Distal Femur & Patella

Accepted Answer

Left Distal Femur

1. The medial condyle “curves” to the LEFT from anterior (top) to posterior (bottom)
2. The lateral condyle, when cut, has its cut edge “facing” LEFT

Left Distal Femur

Right Distal Femur

1. The medial condyle “curves” to the RIGHT from anterior (top) to posterior (bottom)
2. The lateral condyle, when cut, has its cut edge “facing” RIGHT

Right Distal Femur

Left Patella

1. Position the graft with the apex pointing “down”
2. The graft is divided into medial and lateral facets, separated by a Vertical Ridge that runs from superior to inferior down the middle of the graft, generally in-line with the apex
3. The lateral facet will be on the LEFT side of the graft/ridge. In general, the lateral facet is larger and has a smoother, more concave curvature compared to the medial facet
“Lat is Flat”
4. The medial facet will be on the right side of the graft/ridge. This facet is typically smaller, and may have a more irregular and convex curvature
5. The medial facet may also feature an additional “bump and dip”, known as an Odd Facet

Left Patella

Right Patella

1. Position the graft with the apex po

Question 3

Left/Right Graft Designation: Tibial Plateau & Meniscus

Accepted Answer

Right Tibial Plateau

Position the graft with the tibial tuberosity (anterior) facing “up”
The lateral meniscus will be on the RIGHT. It is smaller and features a tighter curvature
“Lateral is Loopy”
The medial meniscus will be found on the left. It will be larger and have a wider curvature compared to the lateral meniscus
"Medial = Ear-Shaped"

Right Tibial Plateau

Left Tibial Plateau

Position the graft with the tibial tuberosity (anterior) facing “up”
The lateral meniscus will be on the LEFT. It is smaller and features a tighter curvature
“Lateral is Loopy”
The medial meniscus will be found on the right. It will be larger and have a wider curvature compared to the lateral meniscus
"Medial = Ear-Shaped"

Left Tibial Plateau

Right Medial Meniscus

The medial meniscus is narrower at the anterior insertion, and wider at the posterior insertion
Position the graft for a top-down view, and so that the anterior aspect is facing “up”
The right medial meniscus will make a C shape

Right Medial Meniscus

Left Medial Meniscus

The medial meniscus is narrower at the anterior insertion, and wider at

Question 4

CMC vs MCP

Accepted Answer

CMC vs MCP Joints

This Job Aid is available to help with identifying hand/wrist grafts that are sent for processing already dissected, and to help guide the dissection for tissue sent as whole hand/wrist en-blocs.

||| Please take photos in the supplier app of the tissue as it is unwrapped/prior to processing. This allows JRF to collect feedback for recovery groups.

Figure 1: Right Hand/Wrist Bones Overview

Carpometacarpal (CMC) Joint

The five joints in the wrist that articulate the distal row of carpal bones and the proximal bases of the five metacarpal bones.
Where the wrist meets the hand
Note the knobby/club-like shape of the metacarpal head (figure 2). This is distinct from the more trochlear/condylar shape of the proximal phalanx head found at the most distal component of the MCP graft (figure 3).
Note the articular surface of the trapezium bone.
The most commonly requested CMC joint is that of the thumb (1st digit). This graft comes from the thumb-pad area of the palm of the hand and the wrist.

Figure 2: Palmer view (supine) of a processed right 1st (thumb) CMC Joint

Metacarpophalangeal (MCP) Joint

Situated between the metacarpal bones and the proximal phalanges of the fingers.
Where the fingers meet the hand
Note the trochlear/condylar s

Question 5

Cartilage Defect Identification

Accepted Answer

Defect Code #1: Bruising

Discolored cartilage due to blood pooling under the tissue.
Result of trauma. Look for other signs of trauma on surrounding bone and soft tissue.
Affected area is typically faint/light red in color.
Deeper, more severe bruises will be darker in color (crimson, purple). || Always Mark.

Superficial Bruising

Deeper Bruising

Defect Code #2: Laceration

A deep, thin cut through the cartilage.
Usually the result of an errant scalpel during tissue recovery or processing.
Typically seen on femoral/humeral heads, and on the posterior aspect of femoral condyles. || Always Mark.

Laceration on a humeral head.

Laceration on the posterior of a hemicondyle.

Defect Code #3: Rough Area

Rough Areas present as an area of gritty texture or ‘feel’.
Normal “wear & tear” acquired through articulation. Top layer of cartilage intact.
In minor cases Rough Areas look identical to pristine cartilage. These areas do not need to be marked and should be graded as pristine.
As severity increases, light may reflect off the Rough Area differently than unaffected cartilage. These areas

Question 6

Left/Right Graft Designation: Distal Tibia & Talus

Accepted Answer

Right Distal Tibia

Position the graft so that the lateral or “open” side is facing the observer
The medial malleolus topography slopes down toward the RIGHT

Right Distal Tibia

Left Distal Tibia

Position the graft so that the lateral or “open” side is facing the observer
The medial malleolus topography slopes down toward the LEFT

Left Distal Tibia

Right Talus

Position the graft anatomically (cut end facing “up”)
The lateral process will be on the RIGHT

Right Talus

Left Talus

Position the graft anatomically (cut end facing “up”)
The lateral process will be on the LEFT

OP301.JA03 REV00

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