Intraoperative ligament laxity influences functional outcome 1 year after total knee arthroplasty

Abstract

Purpose To find out if there is an association between ligament laxity measured intraoperatively and functional outcome 1 year after total knee arthroplasty (TKA).MethodsMedial and lateral ligament laxities were measured intraoperatively in extension and in 90° of flexion in 108 patients [122 knees; median age 70 (range 42–83) years]. Mechanical axes were measured preoperatively and at 1-year follow-up. Outcome measures were the Knee Injury and Osteoarthritis Outcome Score (KOOS), the Knee Society Clinical Rating System, the Oxford Knee Score and patient satisfaction. The relationships between laxity and outcome scores were examined by median regression analyses.ResultsPost-operative mechanical axis had a significant effect on the association between ligament laxity and KOOS. Therefore, the material was stratified on post-operative mechanical axis. In perfectly aligned and valgus-aligned TKAs, there was a negative correlation between medial laxity and all subscores in KOOS. The most important regression coefficient (β) was recorded for the effect of medial laxity in extension on activities of daily living (ADLs) (β = −7.32, p < 0.001), sport/recreation (β = −6.9, p = 0.017) and pain (β = −5.9, p = 0.006), and for the effect of medial laxity in flexion on ADLs (β = −3.11, p = 0.023) and sport/recreation (β = −4.18, p = 0.042). ConclusionsIn order to improve the functional results after TKA, orthopaedic surgeons should monitor ligament laxity and mechanical axis intraoperatively and avoid medial laxity more than 2 mm in extension and 3 mm in flexion in neutral and valgus-aligned knees.Level of evidenceII.

Fibulin-3 fragments are prognostic biomarkers of osteoarthritis incidence in overweight and obese women

“…It's a major risk factor in the development of OA 23 . Joint instability is a determinant of pain in OA 24,25 . Therefore, we can emphasize that a degradation of fibulin-3 is associated with ligament hyperlaxity, joint instability, and subsequently with pain.…”

Balancing of total knee arthroplasty by bone cuts achieves accurately balanced soft tissues without the need for soft tissue releases

“…Aunan et al have shown poor outcome scores (Knee Injury & Osteoarthritis Outcomes Score (KOOS), Oxford Knee Score and Knee Society Score (KSS)) in patients who had >2 mm laxity in extension and >3 mm laxity in flexion 19. Gustke et al also showed statistically inferior KSS (145.3 vs 172.4) and Western Ontario  and McMaster Universities Arthritis Index (WOMAC) scores (23.6 vs 14.5) for unbalanced knees compared with the group of balanced knees 7…”

Knee Function and Subjective Stability Following Total Condylar Arthroplasty in Joints with Preoperative Varus or Valgus Deformity

“…The surgeon decides how stiff or loose total knee he would like to achieve. There are no objective methods to evalu ate ideal collateral tension intraoperatively, the sur geon's experience still being the best guide [3,8,9].…”

“…Głów nym ce lem całko wi tej en do pro te zo pla sty ki sta wu ko la no we go nadal są: znie sie nie bó lu oraz przy wró ce nie funk cji stawu. Od two rze nie ana to micz nej osi ko la na, wła ściwe go ba lan su wię za dło we go i do bre go za kre su ruchu w istot ny spo sób wpły wa ją na po ope ra cyj ny wynik pa cjen ta [3]. W przy pad ku ko lan z przed ope racyj ną de for ma cją ko śla wą bądź szpo ta wą za bieg, endo pro te zo pla sty ki jest bar dziej wy ma ga ją cy ze wzglę du na ko niecz ność nie jed no krot nie roz le głe go uwal nia nia tka nek mięk kich [4], a ta kże uzu peł nie nia ewen tu al nych ubyt ków kost nych [5,6].…”

“…The main goals of total knee replacement, i.e., the relief of pain and re sto ration of joint function, remain unchanged. The restoration of the anatomical knee axis, proper ligamentous balance and good functional range of motion (ROM) has a profound effect on the postoperative outcome [3]. In some cases with preoperative valgus or varus deformity total knee arthroplasty is more demanding because extensive release of soft tissues [4] as well as filling of bony deficiencies are often required [5;6].…”