Effect of Preoperative Joint Space Width on Lateral Meniscal Allograft Transplantation: Outcomes at Midterm Follow-up

Abstract

Background: It remains unclear whether lateral joint space narrowing without severe cartilage loss before meniscal allograft transplantation (MAT) affects clinical outcomes and graft extrusion. Hypothesis: Patients with greater preoperative joint space narrowing would show more graft extrusion, more osteoarthritis progression, and worse clinical outcomes than would those with less narrowing. Study Design: Case-control study; Level of evidence, 3. Methods: We retrospectively evaluated 61 patients who underwent lateral MAT and had a minimum follow-up of 4 to 5 years. The median preoperative joint space width (JSW) on Rosenberg view radiographs was used to classify patients into those with less joint space narrowing (JSW ≥3 mm; group A) and greater joint space narrowing (JSW <3 mm; group B). We compared differences between groups in terms of graft extrusion and articular cartilage loss (modified Outerbridge grade ≥3) on 1-year postoperative magnetic resonance imaging (MRI) scans and changes in JSW and clinical outcomes at the last follow-up. Results: There were 31 patients in group A and 30 patients in group B; the mean follow-up time for all patients was 64.4 ± 10.3 months. All patients showed a significant preoperative to postoperative improvement in outcome scores ( P < .001 for all). The mean preoperative JSW was 3.8 ± 0.9 mm in group A and 2.3 ± 0.4 mm in group B ( P < .001). In group B, there was more graft extrusion on postoperative MRI scans (3.0 ± 0.9 vs 1.9 ± 0.6 mm, respectively; P < .001) and a higher proportion of patients with pathological graft extrusion at final follow-up (43.3% vs 12.9%, respectively; P = .011) compared with group A. At 1 year postoperatively, cartilage loss grade ≥3 was observed at the lateral femoral condyle in 3.2% and 20.0% of patients in groups A and B ( P = .053), respectively, and at the lateral tibial plateau in 3.2% and 30.0% of patients ( P = .006), respectively. There were moderate correlations between graft extrusion and preoperative absolute JSW ( r = –0.471; P < .001) and preoperative relative JSW ( r = –0.428; P = .001). Conclusion: Patients with less preoperative joint space narrowing had less graft extrusion and cartilage loss on 1-year postoperative MRI scans, as well as better radiological and clinical outcomes at midterm follow-up, compared with patients with greater preoperative narrowing.

Tear patterns and locations are different between lateral and medial compartments in patients with early anatomical failure after meniscal allograft transplantation

“…According to previous studies, a poor cartilage status is one of the causes of failure after MAT [4, 18, 32]. In this study, the majority of patients in the lateral MAT group had a high ICRS grade.…”

Comparison of Radiologic Results after Lateral Meniscal Allograft Transplantation with or without Capsulodesis Using an All-Soft Suture Anchor

“…We did not apply universal classification such as Kellgren-Lawrence grade to determine joint space narrowing of the lateral edge [ 39 , 40 ]. Lee et al [ 24 ] revealed that joint cartilage is relatively well maintained when only the lateral edge, not the joint obliteration, is narrow in a considerable number of patients. They showed no significant differences in the ratio of lesions ≥ modified Outerbridge grade 3 between less and moderate joint space narrowing groups.…”

“…The measurements were performed on a picture archiving and communication system (PACS) workstation (Centricity RA 1000; GE Healthcare, Chicago, IL, USA). The absolute JSW was calculated from the lateral edge of the femoral condyle to the lateral edge of the tibial plateau [ 22 , 23 , 24 ] ( Figure 5 ). Our previous study proved that only the lateral edge was observed to be significantly reduced without whole joint obliteration at the time of lateral meniscal allograft transplantation [ 24 ].…”

“…The absolute JSW was calculated from the lateral edge of the femoral condyle to the lateral edge of the tibial plateau [ 22 , 23 , 24 ] ( Figure 5 ). Our previous study proved that only the lateral edge was observed to be significantly reduced without whole joint obliteration at the time of lateral meniscal allograft transplantation [ 24 ]. The relative JSW was calculated by dividing the absolute JSW of the involved knee by the absolute JSW of the uninvolved knee to better standardize the data.…”

“…To detect a difference of 2 mm in graft extrusion between group I and group C with a significance level of 5% and a power of 80%, the required sample size was 16 patients for each group. Therefore, the number of patients in the current study had sufficient statistical power [ 21 , 24 ].…”