Limits...
Diagnosis, causes and treatments of instability following total knee arthroplasty.

Chang MJ, Lim H, Lee NR, Moon YW - Knee Surg Relat Res (2014)

Bottom Line: Particular attention should be given to confirmation of diagnosis for which thorough history taking, complete physical examination and radiographic evaluation are needed.With regard to treatment, identification of the etiology of instability is crucial for establishing proper treatment plans; instability would persist without correction of the cause of the initial instability.For successful revision surgery, balanced medio-lateral and flexion-extension gaps should be achieved.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.

ABSTRACT
Instability following total knee arthroplasty is one of the major causes of revision surgery. In most cases, it can be prevented by using an appropriate prosthesis and a good surgical technique. Particular attention should be given to confirmation of diagnosis for which thorough history taking, complete physical examination and radiographic evaluation are needed. With regard to treatment, identification of the etiology of instability is crucial for establishing proper treatment plans; instability would persist without correction of the cause of the initial instability. For successful revision surgery, balanced medio-lateral and flexion-extension gaps should be achieved. Constrained or rotating-hinge total knee prosthesis should also be considered as an alternative option for certain subsets of patients with instability.

No MeSH data available.


(A, B) Radiographs of the knee with instability after total knee arthroplasty using a cruciate-retaining knee implant. (C, D) Conversion of the femoral component to a posterior stabilized femoral component was performed in revision sugery.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4061408&req=5

Figure 2: (A, B) Radiographs of the knee with instability after total knee arthroplasty using a cruciate-retaining knee implant. (C, D) Conversion of the femoral component to a posterior stabilized femoral component was performed in revision sugery.

Mentions: Flexion instability can occur in patients with PCL-retaining implants who have lax or injured PCL. In these patients, the resultant flexion gap of an inappropriately great size causes flexion instability and even dislocation in severe cases, which can be treated with use of a posterior stabilized implant in revision TKA (Fig. 2). Recent posterior stabilized implants are devised to have a longer jump distance, the distance for the cam to jump over the post, making dislocation a very rare event. However, if varus-valgus instability is present, even these implants may not provide sufficient stability to prevent dislocation.


Diagnosis, causes and treatments of instability following total knee arthroplasty.

Chang MJ, Lim H, Lee NR, Moon YW - Knee Surg Relat Res (2014)

(A, B) Radiographs of the knee with instability after total knee arthroplasty using a cruciate-retaining knee implant. (C, D) Conversion of the femoral component to a posterior stabilized femoral component was performed in revision sugery.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4061408&req=5

Figure 2: (A, B) Radiographs of the knee with instability after total knee arthroplasty using a cruciate-retaining knee implant. (C, D) Conversion of the femoral component to a posterior stabilized femoral component was performed in revision sugery.
Mentions: Flexion instability can occur in patients with PCL-retaining implants who have lax or injured PCL. In these patients, the resultant flexion gap of an inappropriately great size causes flexion instability and even dislocation in severe cases, which can be treated with use of a posterior stabilized implant in revision TKA (Fig. 2). Recent posterior stabilized implants are devised to have a longer jump distance, the distance for the cam to jump over the post, making dislocation a very rare event. However, if varus-valgus instability is present, even these implants may not provide sufficient stability to prevent dislocation.

Bottom Line: Particular attention should be given to confirmation of diagnosis for which thorough history taking, complete physical examination and radiographic evaluation are needed.With regard to treatment, identification of the etiology of instability is crucial for establishing proper treatment plans; instability would persist without correction of the cause of the initial instability.For successful revision surgery, balanced medio-lateral and flexion-extension gaps should be achieved.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.

ABSTRACT
Instability following total knee arthroplasty is one of the major causes of revision surgery. In most cases, it can be prevented by using an appropriate prosthesis and a good surgical technique. Particular attention should be given to confirmation of diagnosis for which thorough history taking, complete physical examination and radiographic evaluation are needed. With regard to treatment, identification of the etiology of instability is crucial for establishing proper treatment plans; instability would persist without correction of the cause of the initial instability. For successful revision surgery, balanced medio-lateral and flexion-extension gaps should be achieved. Constrained or rotating-hinge total knee prosthesis should also be considered as an alternative option for certain subsets of patients with instability.

No MeSH data available.