Rotating-hinge prosthesis for aseptic revision knee arthroplasty: A multicentre retrospective study of 127 cases with a mean follow-up of five years.

BACKGROUND: The use of third-generation rotating-hinge knee prostheses has increased considerably in recent years. The more anatomical design of these prostheses, together with their controlled rotation system that reduces constraints generated by the single degree of liberty, have produced better outcomes. The objective of this study was to evaluate the clinical and radiological outcomes of revision knee arthroplasty for aseptic failure using rotating-hinge prostheses. HYPOTHESIS: The rotating-hinge knee prostheses currently used in France provide significant improvements in function and self-sufficiency of patients undergoing revision knee arthroplasty, with outcomes comparable to those reported with constrained condylar knees. MATERIAL AND METHODS: A multicentre retrospective study was conducted in 17 centres, under the auspices of the SoFCOT. The cohort consisted of 127 patients (127 knees) operated on before 2013. The main reasons for knee revision were aseptic loosening, major instability, mechanical failure, and extensor apparatus failure. Function and self-sufficiency were assessed using the International Knee Society (IKS) score and the Devane score, respectively. Survival was defined with all-cause surgical revision as the end point. RESULTS: Mean follow-up was 67.3±11.8 months (range, 13-180 months). Significant improvements (p<0.001) were seen in the total IKS score (+42 points), the IKS function score (+12 points), and the knee IKS score (+30 points). Paradoxically, the Devane score decreased by 0.44 point. The 5-year survival rate was 77% (95% confidence interval, 0.70-0.85). Postoperative complications developed in 29% of patients (infection, n=12; aseptic loosening, n=11; and fracture, n=7). DISCUSSION: Rotating-hinge prostheses provide satisfactory outcomes of knee arthroplasty revision and remain an effective option for complex cases, confirming our working hypothesis. Self-sufficiency diminishes slightly. The long-term outcomes obtained using rotating-hinge prostheses are, however, less satisfactory than those observed with constrained condylar knees for aseptic TKA revision, and the complication rate is higher, although the population and local circumstances are different. Discernment is therefore in order when determining the indications of rotating-hinge prostheses. LEVEL OF EVIDENCE: IV; retrospective cohort study.

Functional outcome of osteochondral autograft is equivalent in stable knee and in anterior cruciate ligament reconstruction.

INTRODUCTION: Anterior cruciate ligament (ACL) tears are associated in 10% to 20% of cases with extensive traumatic focal osteochondral damage. Ligament reconstruction may require osteochondral autograft for symptomatic osteochondral lesions. Combined ACL and chondral or osteochondral reconstruction is poorly evaluated in the literature; osteochondral reconstruction in stable knee better documented. The objective of this study was to compare functional results after osteochondral autograft transfer (OAT) for significant symptomatic femoral condyle defect, in stable or stabilised knees (concomitant ACL reconstruction). The hypothesis was that functional results are equivalent in both groups. MATERIAL & METHOD: This was a single-centre retrospective comparative observational study of patients consecutively operated on between 2000 and 2018. Fifty patients met the inclusion criteria and were divided into two groups: Group 1 (OAT+ACL, n=13) and group 2 (OAT on stable knee, n=37). The following criteria were recorded at follow-up: pain (VAS), KOOS, IKDC and Lysholm scores and Hughston radiologic score, and time to return to sport. Mean follow-up was 79.7±60 months in group 1 and 86.4±62 months in group 2. RESULTS: Ten patients were included for analysis in group 1 and 30 in group 2. Cartilage lesion size was comparable between groups: 1.6±1.20 cm2 for group 1 and 2.3±1.3 cm2 for group 2 (ns). One complication (infection with favourable course) was observed in group 2. Sport was resumed at 8.7±2.7 vs. 8.4±3.3 months, respectively. Mean subjective scores were respectively 83.3±7.4 and 75.4±14 for Lysholm, 89.7±7.8 and 89.7±19.6 for KOOS, 78±13.7 and 72.2±12.9 for subjective IKDC, 0.5±0.5 and 0.8±0.9 for pain on VAS and 3 and 3 for radiological Hughston radiologic score, with no significant differences between groups. CONCLUSION: Symptomatic focal osteochondral lesions treated by osteochondral autograft transfer gives the same outcome on stable or stabilised knee. LEVEL OF EVIDENCE: IV; retrospective study.

Contemporary rotating hinge arthroplasty can safely be recommended in complex primary surgery.

PURPOSE: The objective was to evaluate clinical and radiological outcomes, survival rate and complications of primary contemporary rotating hinged total knee arthroplasty (CRH-TKA). METHODS: Through a national multicenter retrospective study (14 centers), 112 primary CRH-TKA performed between 2006 and 2011 were included. Indications were: severe frontal plane deformity (55%), inflammatory, constitutional, congenital or post-trauma arthritis (26%), ligament laxity (10%), primary osteoarthritis (9%). Population was elderly (68 ± 13), sedentary (37.5% with a Devane score ≥ 3) and with important comorbidities (87% with ASA score ≥ 2). A clinical (KSS, Oxford scores) and radiological evaluation (implant loosening), as well as survival and reoperation rates assessment, were performed. RESULTS: At last follow-up (7 ± 3 years), KSS and Oxford scores were 64 ± 43 and 33 ± 10 each with a significant improvement of both scores overtime (respectively, p = 0.047 and p < 0.001). Twenty-eight complications (25%) were reported: 12 infections, 6 stiffness, 5 aseptic loosening and 5 patellofemoral instabilities. All in all, 91% (n = 102) of implants were still sealed and in place, 6% (n = 7) required revision and 3% (n = 3) were loose but could not undergo revision due to weak general health status. Mortality rate (18%, n = 20), linked to comorbidities, was high. CONCLUSION: Clinical outcomes and survival of primary CRH-TKA are acceptable given the difficult and complex clinical situations it faced, but with high infection rate. In primary surgery, for patients with severe deformity, bone loss or ligament laxity, the use of CRH-TKA can be recommended. The choice of these implants must remain cautious and limited to situations not allowing the use of less constrained implants. LEVEL OF EVIDENCE: Retrospective therapeutic and cohort study, Level III; retrospective case series, Level IV.