Arthroscopic Meniscus Repair

All-Inside Technique

Marc S. Haro, Jeffrey M. Tuman and David Diduch

• All-inside meniscal repair offers many advantages over traditional inside-out or outside-in meniscal repairs. Benefits include decreased operative times, avoidance of the risks associated with secondary incisions, and ease of use of the implants. Implant designs have evolved since their introduction; this has allowed for safe, reliable all-inside meniscal repairs with results that compare favorably with those of more traditional open methods.

Important Points

• Need to identify meniscal tears that are amenable to repair

• Need to be familiar with the specific features of each device used for all-inside meniscal repair including possible suture configuration, deployment mechanism, tensioning method, and location of knots and backstops

Clinical and Surgical Pearls

• Use a portal that affords the most perpendicular approach to the tear.

• Change portals as necessary.

• Vertical mattress suture configurations are optimal for strength and healing.

• Leave suture attached to implants until all implants are in, to allow repeated tensioning.

• Newer, suture-based fourth-generation devices offer definite advantages over previous devices, including adjustable tension, lower profile, and lower chondral risk.

Clinical and Surgical Pitfalls

• Do not attempt all-inside repairs on tears at the meniscocapsular junction or tears that affect the anterior horn.

• Know the specifics of each device, including deployment mechanism, possible configurations of suture placement, and type and location of implants to prevent device misfire or breakage or injury to patient.

Morgan first described all-inside meniscal repair in 1991 ¹ when he used curved suture hooks and accessory posterior portals. Although these initial results demonstrated that all-inside meniscal repairs could be highly successful, they were technically difficult and required accessory incisions. Since this initial description, there has been a significant evolution with regard to surgical techniques and implant designs.

There are many advantages of an all-inside meniscal repair compared with the more traditional open procedures, including the avoidance of secondary incisions and their associated risks, decreased operative times, and the technical ease of insertion. However, to be considered successful, an all-inside meniscal repair must be able to restore the normal anatomy and must have outcomes that compare favorably with those of the more traditional and current gold standard inside-out meniscal repair technique.

In this chapter we briefly describe the evolution of the all-inside meniscal repair and more specifically concentrate on the surgical techniques and implants associated with the latest fourth-generation devices. We specifically describe the FasT-Fix (Smith & Nephew, Andover, MA), the RapidLoc (DePuy Mitek, Raynham, MA), the Omnispan (DePuy Mitek), and the new Sequent device (ConMed Linvatec, Largo, FL). We also briefly describe the Meniscal Cinch (Arthrex, Naples, FL), MaxFire MarXmen (Biomet, Warsaw, IN), and CrossFix (Cayenne Medical, Scottsdale, AZ) devices.

Preoperative Considerations

History

Meniscal injury commonly occurs with a twisting injury to the knee and at times is seen in conjunction with a ligamentous knee injury. Frequently there are joint line tenderness and mechanical symptoms that include catching, locking, and giving way. Swelling typically occurs overnight in the acute setting and on an intermittent, activity-related basis with a chronic tear.

Physical Examination

• Perform full knee evaluation bilaterally.

• Rule out any hip, pelvic, or back disease that may be contributing to “knee” pain.

• Key examination elements for meniscal tears include:

– Presence of an effusion

– Extension deficit (which may indicate a locked meniscal fragment)

– Joint line tenderness

– Positive results of McMurray test and Apley test

Imaging

Radiography

Plain radiographs are helpful in assessing for gonarthrosis as well as limb alignment.

• Standing anteroposterior and posteroanterior flexed views

• Lateral and sunrise views

Other Imaging Modalities

Magnetic resonance imaging can be more than 96% accurate in identifying meniscal lesions and may be used to help confirm their presence.² However, it has not yet been shown to be helpful in predicting whether a tear is reparable.³ The decision for repair versus partial resection usually requires arthroscopic assessment.

Indications

Many factors play a role in meniscal treatment decision making:

• Age of the patient

• Presence of meniscal degeneration, tear size, tear pattern, and vascularity

• Associated knee instability

• Chronicity of the tear

• Integrity of the meniscal body

Longitudinal, peripheral (vascular) tears in the red-red or red-white zones are the most amenable to repair. If there is ligamentous instability, it should be addressed at the time of meniscus repair, if possible, or in the near future if the procedure must be staged. As with other forms of repair, the all-inside technique yields better results with acute, traumatic tears and in those knees undergoing concomitant anterior cruciate ligament (ACL) reconstruction.⁴ Tears that are stable with less than 3 mm of displacement with probing and that are less than 1 cm in length can be left in situ with predictable results.

Contraindications

Relative contraindications to an all-inside repair include the following:

• The anterior horn may not be accessible through anterior portals with any of the available all-inside devices.

• There must be a meniscal rim intact for the anchoring mechanisms of these devices to work appropriately. Hence, meniscocapsular separations are not suited for all-inside repair devices.

• Degenerative tears that have poor potential for healing may be unsuitable.

These situations may be better served with a suture technique, such as the inside-out or outside-in technique, or in the case of degenerative tears, a partial meniscectomy.

Surgical Technique

Setup and Positioning

For knee arthroscopy with meniscal repair, one may use a lateral post or a leg holder. The patient is placed supine. A tourniquet of the appropriate size is placed high on the thigh according to surgeon preference. When a lateral post is to be used, the leg of the bed need not be broken, although it may improve posterior access. With a leg holder, it is important to position the patient far enough down the bed to allow adequate knee flexion for the operation.

After standard arthroscopic portals have been established, a complete diagnostic knee arthroscopy is performed. Meniscal pathology is identified, and if it is amenable to repair, the meniscus is prepared with standard techniques as appropriate, such as gentle rasping of the torn surfaces and more aggressive rasping of the adjacent synovium to stimulate proliferation. For isolated meniscal repair, one may consider biologic augmentation with a fibrin clot. Delivery of the fibrin clot to the tear can be facilitated by use of an absorbable suture. When an ACL reconstruction is performed simultaneously, fibrin clot occurs naturally.

The portal that affords the most perpendicular approach to the tear should be used to place the device. Typically, this will be the contralateral portal (i.e., introduce the device through the lateral portal for placement in the medial meniscal body). It is common to change portals for optimal access as devices are placed around the meniscal rim. If possible, leave sutures attached until all implants have been placed so that they can be retensioned if needed for optimal compression.

First-Generation Repairs

• All inside meniscal repairs were first described by Morgan in 1991.¹

– Curved suture hooks with accessory posterior portals were used to pass sutures across tear (Fig. 55-1).

Figure 55-1 First generation all-inside meniscal repair techniques used curved suture hooks inserted through accessory posterior portals. (Modified from Miller MD: Atlas of meniscal repair. Oper Tech Orthop. 1995;5:70-71.)

– Sutures were then retrieved and tied arthroscopically.

– The procedure was very technically demanding.

– It still placed neurovascular structures at risk.

Second-Generation Repairs

• All-inside devices were developed to be used through standard arthroscopic portals.

• T-Fix (Smith & Nephew)

– Two sutures connected to a polyethylene bar were deployed through a needle to capture the peripheral meniscus or capsule (Fig. 55-2).

Figure 55-2 The T-Fix implant is composed of a braided suture attached to a polyethylene anchor that captures the peripheral meniscus or capsule. The anchor is deployed through a delivery needle inserted into the meniscus. This device requires arthroscopic suture tying to connect adjacent anchors securing the tear.

– The procedure still required arthroscopic square knots that were pushed onto the meniscal surface (no sliding knots), with minimal compression across the tear.

– The surgeon was unable to tension knots after placement.

The second-generation devices had good short-term success rates of 80% to 90%5–7 but, more important, taught surgeons it was possible to safely deliver an all-inside device through standard anterior arthroscopic portals. Unfortunately, the procedures were still somewhat challenging to perform, and the inability to adequately tension the sutures was less than ideal.