Lateral Capsular Stabilization in Lateral Meniscal Allograft Transplantation

Abstract

Background: Stabilization of the lateral capsule to the tibial plateau may decrease midbody extrusion after lateral meniscal allograft transplantation (MAT). However, there is a paucity of literature reporting on postoperative magnetic resonance imaging (MRI) findings after lateral capsular stabilization (LCS) at the time of lateral MAT. Purpose/Hypothesis: The purpose was to describe MRI findings after LCS and compare postoperative extrusion between isolated lateral MAT and lateral MAT with LCS. It was hypothesized that allograft extrusion would be reduced after MAT with LCS but that the stabilized capsule would increase the risk of tears to the capsule or allograft. Study Design: Cohort study; Level of evidence, 3. Methods: Included were patients who underwent lateral MAT with 6-month follow-up MRI. Concomitant LCS was performed for patients with redundant lateral capsule displaced from the lateral tibial plateau as evident on coronal MRI or arthroscopic examination (MAT+LCS group); otherwise, patients underwent MAT only (isolated MAT group). The Lysholm score, Tegner score, and lateral joint space on radiographs were compared between the 2 groups at 2 years postoperatively, and the stabilized lateral capsule and allograft were evaluated using 6-month follow-up MRI. Extrusion, rotation, and position of the allograft bridge were compared between the 2 groups. Regression analysis was performed to identify factors predictive of degree of extrusion. Results: There were 10 patients in the MAT+LCS group and 13 patients in the isolated MAT group. No significant differences were found between groups in preoperative patient characteristics or postoperative Lysholm score, Tegner score, lateral joint space, or MRI parameters. Postoperative extrusion was not related to obliquity angle, position of the bony bridge, or presence of LCS. In the MAT+LCS group, 1 patient showed a tear of the lateral capsule and a radial tear of the allograft, and 3 patients had a meniscocapsular separation at the midbody of the allograft. In the isolated MAT group, 1 patient had a peripheral tear at the midbody, but there was no tear of the allograft in the other patients. Conclusion: LCS did not decrease extrusion of lateral meniscal transplantation, but it can lead to increased risk for graft or capsule tear.

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

“…Masferrer-Pino et al [ 20 ] also reported that major graft extrusion greater than 3 mm occurred in 41.4% of the group (n = 15) that performed the bony fixation technique and 53.3% of the group (n = 14) that performed capsulodesis (trans-osseous suture). Seo et al [ 18 ] reported that when comparing the isolated lateral MAT group (n = 13) and the lateral MAT + capsulodesis using the suture anchor group (n = 10), the mean of graft extrusion in the MRI six months after surgery was 1.2 ± 2.1 mm and 2.6 ± 1.3 mm, respectively. The graft extrusion of the isolated MAT group increased by an average of 1.3 mm six months after surgery compared to before surgery, whereas that of the lateral MAT + capsulodesis group decreased by an average of 1.1 mm.…”

“…Capsulodesis may be an excellent attempt to reduce graft extrusion after MAT, but further biomechanical studies are needed to elucidate how this procedure will affect the physiological meniscal movement. Seo et al [ 18 ] stated that one capsular tear and three meniscocapsular separations occurred among ten patients who underwent MAT + capsulodesis. They hypothesized that the occurrence of these complications might be a limitation of normal meniscal excrusion due to capsulodesis.…”

“…Graft size reduction, anatomic placement of the graft, and peripheral osteophyte excision have been performed to overcome graft extrusion [ 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. Recently, surgeons have been performing capsulodesis, which reduces the space where the graft extrusion may occur by pulling the stretched lateral capsule to the lateral tibial plateau [ 18 , 19 , 20 ]. The capsulodesis includes a method using a suture anchor and another using transosseous sutures, and each surgeon has reported different results on whether it can reduce graft extrusion [ 18 , 19 , 20 ].…”