Anterior cruciate ligament reconstruction in association with medial unicompartmental knee replacement: a retrospective study comparing clinical and radiological outcomes of two different implant design

Abstract

Purpose Unicompartmental knee arthroplasty (UKA) combined with anterior cruciate ligament (ACL) reconstruction has recently been suggested as a feasible treatment option for young and active patients with medial compartment osteoarthritis (OA) and ACL deficiency. The aim of this study is to evaluate retrospectively the outcomes of two different implant designs in patients with medial OA secondary to traumatic ACL rupture, who underwent combined ACL reconstruction and unicompartmental knee replacement. Methods From January 2007, to December 2013, 24 patients with medial OA secondary to ACL rupture underwent medial unicompartmental knee arthroplasty (UKA) and ACL reconstruction. Nine patients received a mobile bearing UKA (Group 1) and fifteen a fixed-bearing one (Group 2). The mean follow-up was 53 ± 8.3 months for Group 1 and 42 ± 6.7 months for Group 2. Knee Society Score (KSS), Western Ontario and McMaster Index of Osteoarthritis (WOMAC) index and radiological evaluation used to assess the implant loosening alignment of the knee joint and tibial slope were recorded pre-operatively and at the last follow-up. Results At the final follow-up, all patients showed statistically significant clinical improvements with respect to the pre-operative values (p < 0.05). No significant difference was observed in WOMAC index and KSS both objective and functional between groups at the last follow-up (KSS obj. 73.4 ± 9.3 vs 77.3 ± 10.5; KSS funct. 86.2 ± 6.2 vs 84.7 ± 5.9; WOMAC 79.3 ± 7.3 vs 81.3 ± 7.6 for Group 1 and 2, respectively). No differences in radiolucent lines were found between the groups. Conclusion The use of different prosthesis design (fixed-or mobile-bearing) during a combined procedure of ACL reconstruction and medial unicompartmental arthroplasty does not affect the middle-term clinical and radiological outcomes.

Fixed- versus mobile-bearing unicompartmental knee arthroplasty: a meta-analysis

“…Li et al 20 reported a greater incidence of radiolucent lines at 2-years postoperatively in the FB group (37% vs. 8%; p = 0.02), while others demonstrated an increased incidence of radiolucent lines in the MB group (10.3% vs. 23.5%, p = 0.229; 69% vs. 24%, p = 0.001) 10,18 . Meanwhile, Andrea et al 22 revealed that no differences were found in RLLs between FM and MB group. Based on the cumulative data, no significant difference was found in the frequency of RLLs between the FB and MB groups (42.0% vs. 19.0%, OR = 0.56; 95% CI 0.10-3.05; p = 0.51).…”

“…Clinical outcomes. Nine studies assessed the Knee Society Score (KSS) 1,[9][10][11][12]15,19,20,22 ; six studies assessed the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score 11,[16][17][18]20,22 ; three studies assessed the Oxford Knee Score (OKS) 5,15,17 ; one study assessed the Italian Orthopedic UKR's Users Group (GIUM) score 9 ; one study assessed the Bristol knee score 5 ; and one study assessed the International Knee Society score 8 . No significant statistical differences were reported between the FB and MB groups on all knee scores measured in these studies.…”

Anterior cruciate ligament reconstruction combined to partial knee replacement in active patients with ACL deficiency and knee osteoarthritis

“…All were published between 2006 and 2019. The search resulted in one comparative case series (Level III) [19], four prospective cohort studies (Level III) [9,12,16,18] and four case series (Level IV) [11,13,17,20]. Average follow-up periods ranged from 2 years to 7.8 years in a longterm study.…”

“…OA was diagnosed pre-operatively using long-leg standing and standard radiographs; in four studies [12,13,18,19] valgus stress radiographs in 20° of flexion were performed. Only in two studies magnetic resonance imaging (MRI) was performed to evaluate the knee joint preoperatively [17,19].…”

“…In order to overcome the shortcomings related to TKR, recently a treatment option combining medial unicompartmental knee replacement (UKR) and ACL reconstruction has been proposed [9][10][11][12][13][14][15][16][17][18][19][20], since there is general agreement that UKR alone should not be performed in ACLdeficient knees [3].…”