Arthroscopy combined with unicondylar knee arthroplasty for treatment of isolated unicompartmental knee arthritis: A long-term comparison

BACKGROUND Knee osteoarthritis is the most prevalent form of osteoarthritis and is becoming the main reason for progressive pain in knee joints. Arthroscopy combined with unicondylar knee arthroplasty(UKA) is one of the effective methods for the treatment of severe unicompartmental knee arthritis. This surgical approach gives us the capacity to explore all the articular cavities and plays a vital role in UKA patient selection. However, some scholars think that the surgical procedure is traumatic and may increase the rate of surgical infection, and its clinical efficacy needs further study.AIM To compare the clinical effect of arthroscopy combined with UKA and UKA alone for patients suffering from unicompartmental osteoarthritis(OA).METHODS A retrospective study was conducted on patients who were diagnosed with unicompartmental OA(Kellgren–Laurence grade ≥ III) and underwent UKA between October 2012 and November 2006. The patients were followed at 3, 6,and 12 mo and every 2 years thereafter. During each follow-up, the radiographic materials, the range of motion of knee and hospital for special surgery(HSS)score, knee society score and knee function score as recorded, and the modes and time of failure and revision details were collected as well.RESULTS Data on 104 patients(118 knees), including 54 patients(60 knees) in the arthroscopy combined with UKA group(group A) and 51(58 knees) in UKA alone group(group B) were collected during an average follow-up duration of 7.25 years, excluding the cases who were lost to follow-up. At the final follow-up,3(5.0%) of 60 knees in group A compared with 4(6.9%) of 58 knees in group B failed and converted to total knee arthroplasty, with no statistically significant difference between the two groups(P = 0.933). The percentage of patients receiving blood transfusion was 40% in group A, significantly lower than that in group B(67.2%; P = 0.003). Total volume of blood transfusion in group A was also significantly lower than that of group B(P = 0.001). Both groups improved significantly after operation in clinical symptoms and functions. HSS score, knee society score, and knee function score increased significantly at the latest followup compared to pre-operation in group A, from 59.6 ± 10.9 to 82.7 ± 9.3(mean difference [MD], 23.2; 95%CI: 19.3-27.0; P = 0.000), 47.3 ± 6.3 to 76.2 ± 13.1(MD,28.9; 95%CI: 25.1-32.7; P = 0.000), and 57.5 ± 6.3 to 75.1 ± 19.6(MD, 17.5; 95% CI:12.1-23.0; P = 0.000); and in group B, from 59.3 ± 15.6 to 84.3 ± 10.1(MD, 23.7;95%CI: 18.9-28.5; P = 0.000), 49.1 ± 9.2 to 75.1 ± 13.2(MD, 24.7; 95%CI: 19.9-29.5; P= 0.000), and 59.3 ± 9.0 to 77.4 ± 13.8(MD, 17.2; 95%CI: 12.8-21.6; P = 0.000).CONCLUSION Arthroscopy combined with UKA and UKA alone both provide benefits in clinical symptom improvement and alignment correction. Arthroscopy combined with UKA does not increase the infection probability and surgical complications,and has an advantage in reducing the total volume of blood transfusion and the percentage of patients receiving blood transfusion.