Re: transtibial bursa

Tony Barr

Description

Title:

Re: transtibial bursa

Creator:

Tony Barr

Date:

8/24/2005

Text:

To expand on comments previously posted by Donnie, Justin, Kim and others,
the below is reply from physician Dr.William Ertl whom has had experiences
with bursas which are common among some amputees and can severally limit
successful prostheic rehabilitation.

Addidtional questions can be directed to Ask The Ertls at
www.ertlreconstruction.com

Q: From Kimberly:

General Topic: transtibial bursa

Bursa Sack Hey Dan and everyone else, I have yet another question to throw
out there at all of you experts. I had my BKA in May 2004, I am up and
walking, running and other things that I probably shouldn't do... However, I
have been seeing my ortho doc, I guess that I have developed a bursa sack at
the tip of my Tibia, at the amputation site. My doc says that I am the only
person he has ever seen that has had this happen, through thousands of
amputations. Well I guess these sacks should go away over time but mine
seems to like me and has, over time, increased to the size of a golf ball
and getting bigger. So, when you look at my leg, it looks fine , till you
hit the end of the stump, then there is this HUGE lump at the end, that is
fluid filled, sounds attractive doesn't it? Anyways, they are going to go in
this Friday, 10-01, and remove it and re sew up the muscles that have
loosened because of this. I guess what I really want to know, am I just the
freak of nature that I think I am, or has anyone else experienced this? Any
help would be appreciated.

A: From Dr. W.Ertl:

 Kim, I am William Ertl MD, Tony Barr had forwarded you inquiry to Jan Ertl
and myself. I hope I can provide some insight into your question(s).

A bursa sac can develop over the end of a prominent object after it gets
irritated. This can occur in natural, uninjured, non-amputated joints. In
amputees, sometimes the distal end of the tibia gets very prominent,
irritated and the bodies response can be to form something, anything, to
protect that area. At times, a bursal sac will develop. This is essentially
a fluid filled area are inflammatory fluid from chronic irritation of that
area. The exact mechanism, to my knowledge, is not entirely understood. But
the end result is a frustrating situation for the patient.

A possibility of why this occurs is the chronic movement between the tibia
and fibula when these are not stabilized. Bridging the tibia and fibula can
prevent this chronic movement and hopefully diminish or remove a source of
irritation. Further, the end of the limb can now become end-bearing allowing
the amputee bear weight on the end of their limb and utilize the remainder
of their residual limb to support the prosthesis. Essentially, the
prosthesis can then become an extension of the residual limb instead of some
place to put a prosthesis.

When there are no complications, the recovery from the Ertl procedure can be
about 6-7 weeks until you get into your first socket and most likely a
prepatory prosthesis. Of course, pain can be multi-factorial, such as in
decreased bone density, neuromas, poor soft tissue balancing, etc. So the
surgeon has to be sure of all causes of pain.

I hope that this has been helpful or at least a start of answering some
questions.

-----Original Message-----
From: Orthotics and Prosthetics List [mailto:<Email Address Redacted>] On
Behalf Of Donnie Priest
Sent: Tuesday, August 23, 2005 9:29 PM
To: <Email Address Redacted>
Subject: Re: [OANDP-L] transtibial bursa

Dear Todd, Justin, et al.

IDEAS ON THE BURSA

I should start by saying that I am not a doctor and have no desire to be
one. However, I would like to put my two cents worth to foster some
discussion about bursas and the amputee. However, I am an amputee and
prosthetist, and have a structural/functionalist logic style.

In the past, I have had three bursas. Each time they were the symptom that
highlighted a bone spur (I was a growing child). I was able to have
modifications done to the prosthesis to accommodate the bursa, but
ultimately had surgeries (after x-rays) to remove the bone spurs. However,
not every bursa is a sign of a bone spur.but it was in my case.

In light of the recent posts, I would like to point out that the prosthetic
socket interface with regard to the residual limb should be considered more
of a fibrous joint than a solid non-moving interface. In the below knee
amputee, during knee contraction the gastroc-soleus complex compresses and
the tibia and fibula move posterior in the socket. This can be seen in a
plastic check socket, a gap may form at the anterior tibia in many socket
situations. In the above knee amputee, the need for posting of the femur
demonstrates that the femur also moves posteriorly as the hamstring muscle
group compresses. Thus, due to the movement of the bones inside the socket,
the socket to residual limb interface should be considered to have
characteristics similar to a fibrous joint.

With this movement, a shear force occurs and the skin adheres by friction to
the socket interface, as well as the bone moves in comparison to the
surrounding muscle tissue. It appears from the recent posts and my very
limited research, that a bursa will form as the body's mechanism to limit
the friction with regard to shear forces. Thus, not only the amount of
movement is important, but also the friction of the interface materials and
the load carried through the area. Specifically, for a bursa on the distal
tibia, the greater the end bearing, the higher the friction becomes.
Further, certain socket types allow for a lower frictional resistance with
regard to the deformation of the soft tissues and movement of the bones
inside the socket. From my personal experience (although more research is
necessary in this area), I believe that a locking gel liner increases the
friction of the residual limb with regard to its ability to deform under
amputee pathologic gait. However, there is also a benefit to this, such as
a longer lever arm and less movement inside the socket. Every amputee is
different, and one needs to evaluate the person to determine what system is
the best for their lifestyle.

Further, the internal characteristics likely play a major role in the
formation of bursas. I would appreciate a trained medical doctor to
elaborate on this. I am under the impression that a nicely beveled bone
allows for and easier movement through the soft tissues as the soft tissues
deform during ambulation. I also believe that the healing process after the
surgery varies from person to person, and thus the smoothness of the cut
bones will vary. I had an excellent surgeon and I obtained my bursas many
years after my surgery, but attributed that to growth since I was an
adolescent at the time of my amputation. I also do not know how the body
heals after an amputation and if the loading effects of end bearing (total
contact) walking can re-stimulate bone formation.

>From my limited reseach, life, and prosthetic experience, the bursa
formation is a compounding issue. In order to limit the friction, the body
creates more fluid (volume). However, by creating more volume in a confined
area (the prosthetic socket), the friction is increased (not decreased).
Thus, with more friction, the body creates a bigger bursa. Thus, it often
cannot heal because the cause is not fixed. In order to fix the cause, the
friction and shear need to be limited. This can be done both
prosthetically, surgically, chemically, by changing one's lifestyle
(walking), and likely in other ways that I am forgetting.

Prosthetically, I would suggest the person see their prosthetist to limit
the shear or frictional force by socket shape, interface type, suspension
type, or loading characteristics. I am not a doctor, so I would refer the
person to a doctor about internal changes and chemical changes. As to ones
lifestyle, that is for the person to decide upon full knowledge of the
situation.

This is my two cents worth about bursas. I hope that it fosters discussion
and leads to a better understanding of both the socket interface and the
physiology as to why a bursa may occur. I would appreciate any opinions as
to my beliefs, especially to the concept that a prosthetic socket to
residual limb interface should be considered a joint and not a rigid body.
Ideally one wants a rigid body for weight transfer, and a movable joint for
shock absorption.with the individual balance achieved based upon the
characteristics of the person using the prosthetic and his or her lifestyle
and basis for happiness.

Sincerely,
Donnie Priest

                          

Citation

Tony Barr, “Re: transtibial bursa,” Digital Resource Foundation for Orthotics and Prosthetics, accessed November 5, 2024, https://library.drfop.org/items/show/225324.