Down syndrome child with dislocated patella

[np313]

I have a 13 year old son with down syndrome.  2 years ago his right hip slipped and had a pin placed.  About a year later he begain having knee pain on the other side.  Doctors told me that in kids knee pain can be defered from the hip foot ankle or it can be the knee.  They kept a close eye on the other hip thinking it may slip also.  It is hard for him to accurately express where the pain is.  After xraying both hips they found the pin in the right hip had grown out of place and needed to be repinned at the same time they suggested pinning the other hip as a precaution.  About 3 weeks after surgery he was in more pain at this point I changed doctors since the original could not find the problem.  My son at this point would not walk.  The new doctor ran a bunch of tests mri, took fluid samples out of the left hip thinking there might be an infection.  Nothing showed up. At this point the doctor suggested taking out the pin in his hip o we did that and he placed a bracket in the knee to stop the growth of one side of his leg in hopes of straightening his leg.   The leg does seem to be straightening however he still will not walk.  Many years ago i took him to the doctor because of hi s abnormal gait.  His patella when sitting would always go out of place but when he stood it would go back.  The doctor explained to me he thought he was walking like that because he was triing to keep the patella in place and stable.  Anyway after all this time in a wheelchair his patella is now dislocated all the time.  The doctor can no longer put it back in place.  It is being suggested now that the pain and reason he does not want to walk is do to the dislocated patella.  I am told the only way to correct this is with surgery.  I am just looking for any information or suggestion someone may have.  My son has had numerous open heart surgerys and I am told this would be a major surgery where the whole side of his leg would have to be opened to release the tendons and ligaments.  I would like to find out somehow if this is the only possible reason there could be for the pain he is having when walking.
Any help is greatly appreciated.

[JainMD]

Hi,
I can understand how disappointing it could be for you as a parent. I can indentify with you being a parent myself.
I would like to tell just a bit about Q-angle.
The Q-angle is formed by drawing an imaginary line from the anterior superior iliac spine to the center of the patella. This line is intersected by a second line from the tibial tuberosity to the center of the patella and continues superiorly along the center of the anterior thigh. The intersection of these two lines is called the Q-angle. A normal Q-angle in males is 10–15°, and in females it is 10–19°. Do not split hairs over angles. An abnormal Q-angle reflects abnormal patellar tracking and suggests an underlying Patello-femoral disorder.
Prognosis of dislocated patella suggests that Overall, 75% of patients are treated successfully with nonoperative means.
The key is to identify patients at risk for recurrence and to treat them more aggressively early in the course.
Long-term results after surgical treatment do not seem to be better than those after nonoperative treatment.
Long-term results of the Elmslie-Trillat osteotomy show improvement of instability, but results deteriorate over time (*).
I think you can start your child on calcium supplements as it will help him in his bone strength.
Start a Calcium supplement which also contains Vitamin D3 in it.
I hope the best for your child.
Keep me informed if you have any queries.
Bye.


*-Carney JR, Mologne TS, Muldoon M, et al. Long-term evaluation of the Roux-Elmslie-Trillat procedure for patellar instability: a 26-year follow-up. Am J Sports Med 2005;33:1220 to 1223

[np313]

Thank you for asking about my son.  The procedure was suppose to be done yesterday.  After they put him out the doctor did some extensive xrays that he would have never cooperated with until he was out.  It showed the the femur was rotated about 40 degrees and the fibula was rotated close to 80 both in different directions.  At that time the procedure to put the patella back in place became a very major surgery.  Cutting both the bones as well as muscle and tendons.  He came out and talked to us to explain this.  He was not sure if after doing this he would be able to walk either, and this might even stop him from crawling as he does now.  We decided to hold off for now that was to big a decision to make at a moments notice.  
The doctor does not seem to think he will get any worse.  Although researching this I see alot of continually progressive problems for people with dislocated patellas.  Doctor said this was very unusual and he has never seen bones misaligned so bad.  Not sure how they got that way.  He thinks it might have started when his hip was pinned.
Anyway wondering if there is a way to even slowly start correcting the rotation even with braces.  Or is the only way to straighten this is with surgery.  Also mentioned down syndrome kids have weeker bones.  Is there any way to strenthen them some.  Such as calcium supplements.
Anyway thanks for asking it has been a very disappointing couple of days.

[JainMD]

Hi,
How is your son doing?
I think it is the same one for which I have mentioned the name before. What is the Q angle for your child?
All the best.
Take care of his recovery and keep me informed regarding his progress.
Bye.

[np313]

I dont recall the name of the procedure he was doing.  Something about a lateral release where he will have to cut from his knee almost to his hip and release everything to get the patella to go into place.
Thank you for your response.

[JainMD]

Hi,
The symptom of you being able to dislocate the patella without much pain suggests that he has dislocation.
Patellar dislocation is when patella is completely displaced out of the Patello-femoral groove, usually laterally.
The doctors are right in saying that his pain is due to knee problems which will be causing some nerve compromise and hence he is having pain.
Surgical stabilization is recommended for recurrent dislocations.
Patients with excessive Q angles (>150°) and recurrent dislocation may benefit from distal realignment via the Elmslie-Trillat or Fulkerson procedure.
You can ask your doctor regarding this above mentioned procedure.
Keep me informed if you have any queries.
Bye.

[np313]

Thank you for your reply sorry I was slow getting back to you.
His patella is completely dislocated to the outside of the knee.  His patella would originally go out of place when he sat.  I was able to move it in and out of position with no pain to  him.  When he begain having pain and ended up using a wheelchair more than walking it became completely dislocated.  At this point it can no longer be moved back into place.  His Doctor when doing the last surgery to remove the pin from the left hip attempted to put his patella in place when he was relaxed under anisthea.  He could not even do it then.  He just tryed to move it in place with his hand.  Not sure what you mean by patellar pathology.  He will not lay his foot flat and weight bear.  His knee is always bent.
After the last surgery where they removed the pin from his hip and placed a bracket in his knee he started thearapy seemed to be doing well for a while and was walking better with his walker then stopped progressing and actually begain having more pain.  They stopped thearapy since he was not making any progress.
He has had xrays and MRI.

Since my son cannot express his pain as you and I can it has been difficut determining the cause of the pain. After many tests we were told that the only thing that could be causing the pain know is the patella.  If he doesnt have surgery to attempt to get it back in place he most likely will not walk any kind of distance again.  At first we were told he might have to cut the femur if it is not straight to make sure the patella aligns correctly.  Talking to the doctor last week he now tells me he believes it has been out of place to long now and cutting bones is not recommended.
Any further info you might have is greatly appreciated.
Thank you

[JainMD]

Hi,
Down syndrome is a common form of mental retardation whose cause is unknown. All patients have extra chromosome 21 material; chromosome non-disjunction usually occurs in female meiosis. The syndrome occurs in all races with equal frequency.
There are various system which are affected in down's child like Nervous, Cardiovascular, and Skin/Exocrine.
Hence children who are affected with Down's syndrome needs repeated intervention.
Patellar dislocation usually refers to lateral displacement of the patella out of its normal alignment in the trochlear groove of the femur.
The patella is held stable by ligamentous forces, muscular forces, and bony anatomy.
Disruption of any of these 3 components can lead to recurrent patellar instability.
Is the patella out of track or at the edge of groove?
I want to find out whether it is dislocation or subluxation?
Does your child held his knee in flexed position whenever he has patellar pathology?
What imaging is being done and what is the result like?
What all treatment has been done till now for patellar dislocation?
Keep me informed if you have any queries.
Bye.