Lehigh Med Summer 2019 - 24

FEATURE

Orthobiologics and
cartilage restoration are
fields of medicine that are

living and viable. The prepared allograft plug
is transferred into the patient. The patient's
bone grows into the allograft bone, which
ultimately provides fixation. This technique
can be used in all the joints of the body. In
years past, finding a donor of similar dimensions was problematic. However, with new
three-dimensional mapping software provided
by MRIs, tissue banks are now able to find
donors with very similar characteristics and
arcs of curvature such that the donor and
recipient morphologies are one and the same.

defects (size of a dime or a nickel), a procedure
called microfracture has existed for decades.
This procedure involves drilling small holes
into the bone, typically done through an
arthroscopic technique. The goal is for the
body to release the subchondral stem cells
naturally and form a small cartilage plug
over the defect. While this new cartilage plug
is not entirely normal (fibrocartilage rather
than articular joint cartilage), the presence
of any cartilage is better than the absence
thereof. The long-term results of this have
been recently called into question. Previously,
there were no other alternatives, but now with
newer solutions, physicians are beginning to
explore other options. Microfracture is still
frequently performed but generally reserved
for smaller defects, as it is easy to perform
and can be done arthroscopically.

It is important to recognize that these
procedures are not intended to treat diffuse
arthritis. These procedures are reserved for
focal cartilage defects. There are several
other factors that can preclude patients from
being potential candidates. These include
obesity, limb malalignment, rheumatologic
disease, ligamentous instability, or meniscal
insufficiency.

constantly evolving.

be performed in one setting as these products
are readily available.

One additional option which deserves its
own discussion is autologous chondrocyte
implantation (ACI). This is a technique that
has been widely available in Europe for several
years. The technique involves a two-stage
procedure. During the first surgery, a small
graft of cartilage is harvested from the patient
through an arthroscopic surgery in one of the
Except for microfracture, most of these
non-weight bearing regions of the knee. The procedures are done through a small open
graft is about the size of a TicTac and sent to incision. They all roughly have the same
a laboratory for enzymatic degradation and post-operative rehabilitation. While the
cell division. After preparation is completed, aforementioned paragraphs provide an
a sheet of live viable cartilage on a porcine introductory discussion of the various options
membrane is produced. These cartilage cells available, there are several other factors that
are living and have the DNA of the patient. play a role in the decision. Not only is the
In a second surgery, about one month from size of the defect important, the depth of the
the first, through an open incision, this cartilage defect, the quality of the underlying
For mid-size defects (size of a quarter), cell-impregnated membrane is secured into a bone, and the location of the defect within
microfracture has poor outcomes, especially prepared site over the cartilage defect. Several the joint have to be taken into consideration.
long term. In these mid-sized defects, there studies have examined this treatment option. It is important that the treating physician
are newer products that can be used to "plug Articular cartilage is seen to grow and fill the individualize the treatment to best suit the
and seal" the cartilage defect. This is analogous defect on second look arthroscopic studies as needs of the patient.
to filling a pothole in the road. These options well as on post-operative histological studies.
termed osteochondral allografts are viable For defects involving the femoral trochlea and
Orthobiologics and cartilage restoration
cartilage products. They have the potential patella where the three-dimensional contour are fields of medicine that are constantly
to grow and form articular cartilage. These is different in every patient, ACI is considered evolving. More research is necessary to
procedures require an open arthrotomy to the gold standard.
determine how best to use these treatments
access the defect and implant the allograft.
to help treatment patients. At the current
The rehabilitation after surgery is similar to
For larger defects, a traditional osteochon- state of technology, judicious discussion and
a microfracture. Early and mid-range studies dral allograft is used. The surgery has been decision-making is necessary to select the
are encouraging. On post-operative histologic performed for over 20 years with a very good patients who best stand to improve. We are
studies, articular cartilage is seen to fill the track record. In a single surgery, the damaged excited to admit that the treatments of today
defect. These products are constantly evolving cartilage and underlying bone is removed will likely become historical discussions in
and improving. Three such products on the from the patient and a similar sized plug is the years to follow as newer techniques and
market are DeNovo (Zimmer), Cartiform fashioned from a fresh cadaveric specimen. treatments are developed.
(Arthrex), and ProChondrix (Stryker). The Because the allograft is fresh and within 45
advantage of these procedures is that they can days of procurement, the cartilage cells are
24 Lehigh County Health & Medicine | SUMMER 2019

Lehigh Med Summer 2019

Table of Contents for the Digital Edition of Lehigh Med Summer 2019