Are varus knees contracted? Reconciling the literature

McAuliffe, Michael J.; Vakili, Ali; Garg, Gautam; Roe, John; Whitehouse, Sarah L.; Crawford, Ross

doi:10.1177/2309499017731445

Cited by 14 publications

(18 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Osteoarthritis has been documented in numerous studies to cause altered tissue laxity in extension or early flexion rather than deeper flexion ranges. [17][18][19][20][25][26][27][28] In a related parameter, the change in lateral sided tissue laxity between 20 and 90 degrees of flexion was significantly negatively correlated with satisfaction outcomes. Practically this means that when greater lateral laxity was seen in early flexion compared with 90 degrees of flexion patients were more satisfied postoperatively which is consistent with the opportunity for surgery to correct this abnormally lax tissue.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Which Pre- and Postoperative Coronal Plane Laxity Parameters Influence Patient Satisfaction and Function after Primary Total Knee Arthroplasty?

et al. 2020

Self Cite

View full text Add to dashboard Cite

Soft tissue balancing, while accepted as crucial to total knee arthroplasty (TKA) outcomes, is incompletely defined as the subject of broad recommendations. We analyzed 120 computer-assisted, posterior stabilized TKA undertaken for osteoarthritis. Coronal plane laxity was measured, in the 91 varus and 29 valgus knees, prior to any bone resection or soft tissue release, and again after implant insertion. Soft tissue laxity parameters were correlated to the American Knee Society Score (2011) at a minimum follow-up of 12 months with a focus on patient function and satisfaction. Thirteen specific laxity parameters showed a significant correlation to satisfaction, one parameter correlated to function, and another to both functional and satisfaction outcomes. Most correlations were weak, the strongest related to postoperative decreases in coronal plane laxity. Greater preoperative varus but not valgus deformity was associated with higher satisfaction scores. Additionally, 30 patients who reported 40 of 40 satisfaction and that their TKA knee felt normal at all times did not have soft tissue balancing parameters distinguishing them from other subjects. Patient satisfaction and function outcomes demonstrated limited correlation to coronal plane soft tissue parameters. It appears that optimizing TKA satisfaction and function is not as simple as producing a narrow range of coronal laxity parameters. The ongoing debate around optimal coronal plane alignment and its subsequent effect on coronal plane soft tissues may not be as independently important as currently argued. Soft tissue balance may need to be considered as a more complex global envelope.

show abstract

Section: Discussionmentioning

confidence: 99%

“…3). [17][18][19][20]23,24 These measurements have been previously validated using modern navigation systems. 20 Once the data were recorded a CAS TKA was performed (►Fig.…”

Section: Methodsmentioning

confidence: 99%

Which Pre- and Postoperative Coronal Plane Laxity Parameters Influence Patient Satisfaction and Function after Primary Total Knee Arthroplasty?

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…19 Our testing methods were consistent with previously described techniques. [14][15][16]19,20,22 It is not possible in an in vivo setting to utilize the same invasive techniques with multiple controlled parameters and measurements that are utilized in cadaver studies given the ethical implications of prolonging surgery particularly in relation to infection and fracture risk. Such studies utilize load application systems requiring fixation screws, intramedullary rods, and multiple transections around the knee.…”

Section: Discussionmentioning

confidence: 99%

“…The measurement technique has been previously described for measurement of coronal laxity in the varus OA knee. 14,15 A medial parapatellar approach to the knee was undertaken.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Highly Satisfied Total Knee Arthroplasty Patients Display a Wide Range of Soft Tissue Balance

et al. 2019

Self Cite

View full text Add to dashboard Cite

Soft tissue balancing while crucial for a successful total knee arthroplasty (TKA) is incompletely defined and the subject of broad recommendations. We analyzed 69 unilateral computer-assisted surgery posterior stabilized (PS) TKA subjects who postoperatively scored ≥36 out of a possible 40 points on the satisfaction section of the American Knee Society score (2011). We examined a range of postoperative coronal plane laxity parameters and the correlation between preoperative and postoperative laxity. Total postoperative coronal laxity arcs at maximum extension and 20 degrees of flexion varied between 2 and 12 and 3 and 13 degrees, respectively. Depending on the position of measurement, medial laxity was between 0.5 and 9.5 degrees and lateral laxity between 1 and 12 degrees. The change in laxity between maximum extension and 90 degrees of flexion demonstrated a range of 7 degrees medially and 12 degrees laterally. The total coronal arc of movement did not affect functional outcomes. A moderate correlation of 0.452 and 0.424 was seen between initial and postoperative total coronal laxity arcs in maximum extension and 20 degrees of flexion, respectively. The individual variability for each measured parameter within our cohort demonstrates TKA satisfaction is not as simple as producing a narrow range of coronal laxity parameters and that as with many body systems considerable variation is still consistent with excellent function. Our findings help to define acceptable balance parameters for PS TKA. It does not appear necessary to closely match postoperative laxity to that present preoperatively.

show abstract

Functional knee phenotypes of OA patients undergoing total knee arthroplasty are significantly more varus or valgus than in a non-OA control group

Jenny

Baldairon

Hirschmann

2021

Knee Surg Sports Traumatol Arthrosc

View full text Add to dashboard Cite

Purpose The aim of this study was to analyse the coronal alignment of a large population of patients undergoing total knee arthroplasty using a modern classiication of the knee phenotypes found in a population of non-osteoarthritic individuals. Methods Five hundred and four navigated total knee arthroplasties were included in the OA group. The following angles were measured with a computer image-free navigation system: mechanical femorotibial angle measured on the medial side without stress and with maximum manual stress to reduce deformation, and medial distal femoral mechanical angle. The native medial distal femoral and medial proximal tibial angles (coronal orientation of the femoral or tibial joint line after correction of wear) were calculated. The data were analysed as categorical data. These data were then compared with those published in a non-arthritic population, considered as a control non-OA group. The main criterion was the percentage of subjects with normal overall coronal alignment, deined by the association of a normal native medial distal femoral angle and a normal native medial proximal tibial angle. The secondary criteria were the percentages of subjects with normal medial femorotibial mechanical angle, normal native medial distal femoral angle and normal native medial proximal tibial angle. The inluence of gender on primary and secondary criteria in the study group was analysed. The most frequent phenotypes in the study group were identiied. Results Normal overall coronal alignment was found in 66 patients in the OA group (12.7%) and 76 patients in the non-OAgroup (24.7%) (p < 0.01 after adjustment by gender). There were fewer normal patients in the OA-group than in the non-OAgroup for medial femorotibial mechanical angle, native medial distal femoral angle and native medial proximal tibial angle. In females, there were signiicantly fewer normal medial femorotibial mechanical angle. In males, there were signiicantly more cases with native medial distal femoral varus and in females more cases with native medial distal femoral valgus. There was no signiicant inluence of gender on native medial proximal tibial angle. There was a wider distribution of the phenotypes in the OA-group than in the non-OA-group. ConclusionThe distribution of functional phenotypes of the knee in patients undergoing total knee arthroplasty is diferent from those found in a reference non-osteoarthritic population. Level of evidence Level III-retrospective cohort study.

show abstract

Are varus knees contracted? Reconciling the literature

Cited by 14 publications

References 25 publications

Which Pre- and Postoperative Coronal Plane Laxity Parameters Influence Patient Satisfaction and Function after Primary Total Knee Arthroplasty?

Which Pre- and Postoperative Coronal Plane Laxity Parameters Influence Patient Satisfaction and Function after Primary Total Knee Arthroplasty?

Highly Satisfied Total Knee Arthroplasty Patients Display a Wide Range of Soft Tissue Balance

Functional knee phenotypes of OA patients undergoing total knee arthroplasty are significantly more varus or valgus than in a non-OA control group

Contact Info

Product

Resources

About