Biomechanical comparison of arthroscopic repair constructs for radial tears of the meniscus.

BACKGROUND: Radial tears of the meniscus represent a challenging clinical scenario because benign neglect and partial meniscectomy have both been shown to have negative biomechanical and long-term clinical consequences. HYPOTHESIS: Complex suture repair constructs have higher failure loads and stiffness values compared with simple constructs. STUDY DESIGN: Controlled laboratory study. METHODS: After radial transection of human cadaveric menisci, simulated tears were repaired arthroscopically by use of 1 of 4 repair constructs: (1) 2 inside-out horizontal sutures, (2) 2 all-inside horizontal sutures, (3) an all-inside Mason-Allen construct consisting of 4 sutures, or (4) an all-inside construct consisting of a figure-of-8 suture plus 1 horizontal suture. Meniscus specimens were harvested and tested to failure on an Instron machine. The Kruskal-Wallis test was used to evaluate for significance of maximal failure load and stiffness between groups. RESULTS: The mean maximum failure loads were 64 ± 20 N (inside-out horizontal construct), 75 ± 16 N (all-inside horizontal construct), 86 ± 19 N (Mason-Allen construct), and 113 ± 22 N (figure-of-8 plus horizontal construct). Interconstruct comparison revealed a statistically significant difference between the figure-of-8 plus horizontal construct and all 3 remaining constructs (P < .02) as well as the Mason-Allen construct when compared with the inside-out horizontal construct (P < .01). Statistical significance was not found between the all-inside horizontal construct and the Mason-Allen construct or between the all-inside horizontal construct and the inside-out horizontal construct (P = .2 and .7, respectively). Stiffness values were lower for the inside-out construct compared with the all-inside constructs (P < .05). CONCLUSION: Complex all-inside repair constructs had significantly higher failure loads than a conventional, simple inside-out suture repair construct for repair of radial meniscal tears. Stiffness values among the all-inside groups were greater than those for the inside-out group. CLINICAL RELEVANCE: Arthroscopic techniques are presented to produce stronger radial meniscal tear repairs.

Biomechanical comparison of arthroscopic repair constructs for meniscal root tears.

BACKGROUND: Complete meniscal root tears render the meniscus nonfunctional. Repair constructs have been presented and tested; however, prior studies have evaluated suture patterns placed ex vivo without simulating an in vivo surgical setting. This study introduces a new double-locking loop suture pattern and compares its biomechanical properties and execution time with commonly used suture patterns. All constructs were performed using an all-inside arthroscopic technique. HYPOTHESIS: Complex suture repair constructs have higher failure loads, stiffness, and execution times compared with simple constructs. STUDY DESIGN: Controlled laboratory study. METHODS: Sutures were placed arthroscopically into the posterior horn root region of the medial and lateral menisci in 21 cadaveric knees. Four repair constructs were evaluated: 2 simple sutures (2SS), 1 inverted mattress suture (1MS), 1 double-locking loop suture (1DLS), and 2 double-locking loop sutures (2DLS). In total, 40 posterior meniscal roots were tested, with 10 trials for each construct. After arthroscopic placement of the root repair constructs, each meniscus was explanted and tested to failure on a uniaxial materials testing machine. The Kruskal-Wallis test was used to evaluate for the significance of maximum failure loads and stiffness between groups. RESULTS: The mean maximum failure loads were 137 ± 49 N (2SS), 126 ± 44 N (1MS), 186 ± 43 N (1DLS), and 368 ± 76 N (2DLS). Interconstruct comparison revealed a statistical difference between 2DLS and all 3 remaining constructs (P < .01) and 1DLS when compared with 2SS and 1MS (P < .01 for both). Statistical significance was not found between 2SS and 1MS (P = .8). The mean times for repair of the 4 fixation techniques were 1.8 ± 0.9 minutes (2SS), 2.4 ± 1.9 minutes (1MS), 4.7 ± 2.0 minutes (1DLS), and 5.4 ± 0.6 minutes (2DLS). CONCLUSION: The double-locking loop suture repair technique had significantly higher failure loads compared with the 3 other methods tested. As the complexity of repair constructs increases, failure loads and surgical times increase. CLINICAL RELEVANCE: Complex suture patterns can be placed via an all-inside arthroscopic technique delivering higher failure loads for meniscal root repair with little increase in surgical time.

The circumferential compression stitch for meniscus repair.

Over the past 30 years, many patients have benefited from arthroscopically assisted meniscus repair surgery and its ability to preserve a healthy knee. Although techniques have evolved, the basic premise of central-to-peripheral needle penetration across the tear with fixation into the capsular region immediately peripheral to the meniscus has remained. Suture repair techniques that involve encircling the tear have been discussed but have remained largely impractical because of the anatomic constraints of the arthroscopic knee. A suture-passing technology designed to function within these constraints was recently made available from Ceterix Orthopaedics (Menlo Park, CA). It allows surgeons to arthroscopically place circumferential sutures around meniscus tears to provide uniform, anatomic compression of the tear edges through an all-inside technique. This stitch is likely to improve healing rates and safety, as well as to enable repair of tears that were previously considered difficult or impossible to sew. The purposes of this note and accompanying video are to show the feasibility of placing all-inside circumferential compression stitches to treat tears of the knee meniscus and to discuss the potential benefits of such techniques.