Unconstrained arthroplasty in type II valgus knees: posterior stabilized or cruciate retaining?
OBJECTIVE
Type II valgus knees are defined by medial collateral ligament laxity. This paper studies the results of posterior stabilized (PS) and cruciate retaining (CR) knee implants in type II valgus knees.


METHODS
From 1999 to 2009, there were 100 type II valgus knees in 95 patients eligible for study (63 PS, 37 CR). Patients had prospectively collected clinical data up to 2 years after surgery.


RESULTS
At 24 months after surgery, the CR group had reduced range of motion (PS: median 126.0°, CR: median 114°; n.s.) and a marginally but statistically significant increased valgus alignment (PS: median 5°, CR: median 6°; p = 0.011). Despite this, both groups produced equal and marked improvements in SF-36, function score and knee score of the Knee Society score, and Oxford knee score.


CONCLUSIONS
Overall, both PS and CR implants performed equally well in type II valgus knees at 24 months post-operatively. Further longer-term studies would be warranted to assess for late instability.


METHODS
Retrospective, Level III.
Department of Orthopaedic Surgery, Singapore General Hospital, 20 College Road, Level 4, Singapore, 169856, Singapore, med80199@yahoo.com.
Chia Liang
CL
Ang
Stephanie
S
Fook
Shi Lu
SL
Chia
Pak Lin
PL
Chin
Ngai Nung
NN
Lo
Seng Jin
SJ
Yeo
D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation* / Q000379:methods; D060751:Bone Retroversion / Q000150:complications / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000150:complications / Q000601:surgery*; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D016896:Treatment Outcome