Effect of lesion location on fixation strength of the meniscal viper repair system: an in vitro study using porcine menisci.

PURPOSE: The Meniscal Viper Repair System (Arthrex, Naples, FL) is a novel suture-based all-inside meniscal repair system. This study was performed to test whether the Meniscal Viper Repair System would provide superior fixation characteristics for vertical longitudinal meniscal lesions located closer to the periphery compared with those located further away from the periphery. METHODS: Vertical longitudinal lesions were created either 1 to 2 mm or 3 to 4 mm away from the periphery of porcine menisci. After repair with the Meniscal Viper Repair System, fixation characteristics were studied during cyclic (500 cycles, 5 to 50 N) and load to failure testing (5 mm/min) in a servo hydraulic device. RESULTS: Meniscal lesion repair location did not show significant differences in displacement or stiffness during cyclic testing. During load to failure testing, meniscal lesion repairs located 1 to 2 mm from the periphery showed superior load at failure (188.8 +/- 45.4 N) compared with repairs located 3 to 4 mm from the periphery (114.4 +/- 35.0 N) (P = .01). Stiffness and displacement during load to failure testing did not show statistically significant differences. CONCLUSIONS: The Meniscal Viper Repair System provides stronger meniscal repair strength when lesions are located within 1 to 2 mm of the periphery. CLINICAL RELEVANCE: The Meniscal Viper Repair System is better suited for repair of peripheral meniscal lesions located within 1 to 2 mm of the periphery. For lesions located in zone 2 (within the central 50%), careful assessment of their distance from the periphery is recommended. For lesions located more than 3 to 4 mm away from the periphery, alternative repair systems or augmentation with other devices may be prudent.

A biomechanical comparison of the FasT-Fix meniscal repair suture system and the RapidLoc device in cadaver meniscus.

PURPOSE: This biomechanical study compared the fixation characteristics of horizontally or vertically implanted FasT-Fix devices (Smith & Nephew, Endoscopy Division, Andover, MA) consisting of two 5-mm PLLA suture T-bar anchors with a pretied self-sliding knot (No. 0 nonabsorbable, USP, braided polyester suture material) and the RapidLoc device (Mitek Surgical Products, Westwood, MA) consisting of a PLLA T-bar anchor or "backstop," a connecting suture (No. 2 nonbiodegradable Ethibond; Ethicon, Somerville, NJ), and a PLLA grommet, for repairing posterior third lesions in human menisci. TYPE OF STUDY: Controlled laboratory biomechanical study. METHODS: After repair of a vertical longitudinal meniscus lesion with either vertically or horizontally implanted FasT-Fix devices or RapidLoc devices, 3 groups of 6 specimens underwent cyclic loading (5 mm/minute, cycling between 5 and 50 N at 1 Hz for 500 cycles) before load to failure testing on a servo hydraulic device. One-way analysis of variance and Tukey HSD post hoc tests were used to evaluate group differences (P < .05). RESULTS: The vertical FasT-Fix device group (3.2 +/- 0.49 mm) had less displacement after cyclic testing than either the horizontal FasT-Fix (4.4 +/- 0.73 mm, P = .003) or the RapidLoc (4.6 +/- 0.22 mm, P = .002) device groups. The vertical FasT-Fix device group had greater stiffness during cyclic testing (14.4 +/- 2.1 N/mm) than the horizontal FasT-Fix (10.4 +/- 1.6 N/mm, P = .0001) or the RapidLoc (9.7 +/- 0.44 N/mm, P = .0001) device groups. During load to failure testing, the vertical FasT-Fix group (125.3 +/- 39 N) had 28% greater strength than the horizontal FasT-Fix device group (89.7 +/- 14 N, P = .02) and 30% greater strength than the RapidLoc device group (87.1 +/- 13 N, P = .028), whereas displacement and stiffness did not show statistically significant group differences. CONCLUSIONS: The vertical FasT-Fix group had superior biomechanical characteristics for meniscal fixation during cyclic and load to failure testing compared with horizontal FasT-Fix or RapidLoc devices. CLINICAL RELEVANCE: Although the RapidLoc devices provided fixation characteristics comparable to horizontally implanted FasT-Fix devices, vertically implanted FasT-Fix devices may provide superior all-inside fixation.

Allograft anterior tibialis tendon with bioabsorbable interference screw fixation in anterior cruciate ligament reconstruction.

For a variety of reasons, bone-patellar tendon-bone and Achilles tendon allografts have been used more commonly in anterior cruciate ligament reconstruction. Soft-tissue allografts used mainly are the semitendinosus, gracilis, and occasionally the quadriceps tendons. The anterior tibialis tendon is a thick, strong tendon that can be prepared with one doubling of the graft, has a large cross-sectional area, and has been shown to be stronger than semitendinosus, gracilis, patellar tendon, and native anterior cruciate ligament. Use of allograft shortens surgical time, eliminates graft harvest-site morbidity, and allows for a large supply of grafts for repeat or multiple ligament procedures. This graft can be fixed to the femoral and tibial bone tunnels with bioabsorbable interference screws for a hardware-free, completely endoscopic procedure. Two- to 4-year results of allograft procedures are comparable to autograft procedures, and there have been no early failures with this described technique using anterior tibialis tendon.