CHAPTER 45 – 








CHAPTER 45 – Arthroscopic Meniscal Repair: Outside-In Technique from Cole & Sekiya: Surgical Techniques of the Shoulder, Elbow and Knee in Sports Medicine on MD Consult



















CHAPTER 45 – Arthroscopic Meniscal Repair: Outside-In Technique

Fintan J. Shannon, FRCS (Tr & Orth),
Scott A. Rodeo, MD

The anatomy, structure, blood supply, and function of the menisci are well understood. There is now strong evidence supporting the preservation of viable meniscal tissue in an otherwise intact knee.

All-inside, inside-out, and outside-in techniques are useful options for repair of meniscal tears. The outside-in technique was first described by Warren[14] as a method to decrease the risk of peroneal nerve injury during lateral meniscal repair. The choice of which technique is used is predominantly affected by the surgeon’s experience and the morphologic features of the tear. However, not all tears should be repaired, and surgical outcome for these repairs is determined by careful meniscal and patient selection.



Preoperative Considerations


History

Acute tears typically present with focal pain and mild swelling. Unstable meniscal tears may present with catching or locking. The patient usually recalls a twisting injury or deep flexion event. A longer history or history of antecedent pain, locking, swelling, or instability may indicate chronic meniscal disease.

Details of previous treatments and operative reports are helpful. Other factors to be considered are the age of the patient, the expected compliance of the patient with rehabilitation, and the patient’s physical ability to be non–weight bearing postoperatively.


Physical Examination

Nonspecific important observations:

       Alignment: neutral, varus, or valgus
       Gait: is it antalgic?
       Loss of end range of motion: deep flexion and full extension
       Focal pain
       Painful clicking

Signs supportive of meniscal tear:

       Effusion
       Soft block to extension: suggests displaced fragment (bounce test)
       Pain on passive deep flexion
       Focal tenderness along joint line
       Pain with meniscal compression: McMurray and Apley tests


Imaging


Radiography

       Weight-bearing views: anteroposterior in full extension and posteroanterior in 45 degrees of flexion
       Non–weight-bearing lateral view in 45 degrees of flexion
       Merchant view of patellofemoral joint
       Long-cassette mechanical axis view to evaluate alignment


Other Modalities

       Magnetic resonance imaging

Evaluate meniscal tear location (inner, middle, or outer third) and amount of abnormal meniscus, intrameniscal signal, articular cartilage, and cruciate ligament integrity. Increased intrameniscal signal indicates poorer healing potential.


Indications and Contraindications

When the history and preoperative imaging suggest that a meniscal tear may be amenable to repair, careful preoperative counseling of the patient is essential. The patient must be aware that postoperative restrictions are significant, and the patient’s compliance is key to a successful outcome.

The ideal candidate for an outside-in repair is a young, compliant patient with a short history of pain, a stable knee, and a vertical longitudinal tear in the red-red zone of a meniscus. Other specific indications include suturing of a meniscal replacement (allograft or replacement device, such as a collagen meniscus implant) and suturing of a Wrisberg-type discoid lateral meniscus in a small knee. Specific advantages are precise needle placement with reduced risk of chondral injury and relative ease of technique for anterior horn tears.

Relative contraindications for meniscal repair in general include degenerative flap or horizontal cleavage tears, partial-thickness tears, stable tears (<2 cm), tears in the white-white zone, and patients with an unstable or anterior cruciate ligament (ACL)–deficient knee. [5] [10] Radial tears, particularly in the posterior horn, are reparable where there is a rich blood supply. Better healing has been demonstrated with lateral meniscal tears, and therefore indications for lateral meniscal repair are broader. Small, vertical, longitudinal tears posterior to the popliteus tendon and small avulsion tears of the posterior horn in the setting of injury to the ACL may be observed.[3]

Other contraindications include far posterior tears (difficult to place sutures perpendicular to tear; use inside-out technique or all-inside), complex tears, older patients (older than 50 years), and chronic tears with deformation of the meniscus.


Surgical Technique


Anesthesia and Positioning

The decision regarding type of anesthesia is generally made between the anesthesiologist and the patient. Spinal anesthesia is effective for outpatient knee arthroscopy surgery and meniscal repair work. Femoral nerve blocks, although helpful, can potentially delay rehabilitation and return of quadriceps function.

Standard setup includes a thigh tourniquet and a lateral post. The limb should be placed on the operating table in such a position that when the end of the table is flexed, the end of the thigh protrudes over the table break. This provides access to the posteromedial and posterolateral corners of the knee.


Specific Knee Positions

       10 degrees of flexion with valgus stress for medial meniscal repair. The saphenous nerve and vein lie anterior to the palpable semitendinosus tendon; therefore, you work posterior to them. This position is good for posterior and middle-third tears.
       50 to 60 degrees of flexion for anterior horn of medial meniscus. Work anterior to pes anserinus tendons and saphenous nerve branches.
       90 degrees of flexion for lateral meniscal repair: figure-of-four position. The needle must remain anterior to the biceps tendon to avoid peroneal nerve injury.


Surgical Landmarks, Incisions, and Portals


Landmarks

       Patella
       Patellar tendon
       Joint line–plateau: mark with surgical marker
       Fibular head, biceps tendon


Incisions and Portals

Use a standard anterolateral portal for initial arthroscopy. Determine the best anteromedial portal after spinal needle confirmation of correct height and location. Portal location is less important in this type of repair, whereas instrument trajectory is crucial in all-inside and inside-out repairs. For the lateral meniscus, use the high anteromedial portal.

The large posterior incisions are not necessary in performing the outside-in repair. However, it is difficult to place perpendicular sutures for far posterior tears, and oblique suture orientation compromises fixation stability.[13] In performing the dissection down to capsule for needles introduced posteromedially or posterolaterally, consider underlying superficial structures:

       Posteromedial: saphenous nerve, medial collateral ligament
       Posterolateral: peroneal nerve, lateral collateral ligament


Examination Under Anesthesia

Examination of range of motion and stability is performed before sterile preparation and draping of the lower extremity.


Diagnostic Arthroscopy

       Joint surfaces
       ACL
       Location, orientation, and stability of tear. Visualization of the posterior horn of the medial meniscus is facilitated by inserting the arthroscope through the anterolateral portal and passing it between the posterior cruciate ligament and the medial femoral condyle.
       Abrade surfaces of tear to make a bleeding bed with a rasp or 3.5-mm full-radius resector.[2] Consider the posteromedial portal for this purpose. Flex knee, palpate pes anserinus tendons, and introduce spinal needle anterior to these. The portal incision is posterior and proximal to the medial joint line.
       Abrade synovial membrane adjacent to tear to stimulate additional vascularity.[9]


Specific Steps (
Box 45-1

)


Equipment

       18-gauge spinal needles
       Arthroscopic grasper
       Suture: rigid, monofilament; No. 0 polydioxanone (PDS)

Box 45-1 

Surgical Steps

   1.    Prepare meniscus
   2.    Locate skin surface over meniscal tear
   3.    Pass one spinal needle
   4.    Make small skin incision around needle
   5.    Pass second spinal needle
   6.    Secure sutures


 Prepare Meniscus

Prepare the meniscus by gentle débridement or abrasion of the edges of the tear and the synovial fringe that appears on the superior and inferior surface of the capsule. Use a rasp or 3.5-mm full-radius resector.


 Locate Skin Surface over Meniscal Tear

Locate the skin surface over the meniscal tear by use of topographic landmarks, palpation, and transillumination. Transillumination minimizes injury to cutaneous nerves and vessels.


 Pass One Spinal Needle

Pass one spinal needle through the skin, subcutaneous tissue, capsule, and outer edge of the meniscus across the tear and through the inner meniscus (
Fig. 45-1

). The needle can exit either the superior (femoral) or inferior (tibial) surface of the meniscus. A probe or small loop curet may be used to control needle position or to provide counterpressure on the meniscus while the needle is being passed. Do not pass through the inner rim of the meniscus; this is thin tissue that will tear or fold when sutures are tensioned. Consider curved needles for posterior tears.

Figure 45-1 
Once you are satisfied with needle position, make a small skin incision.



 Make Small Skin Incision Around Needle

Make a small skin incision around the needle and spread the subcutaneous tissue down to the capsule (
Fig. 45-2

). Be careful to consider the saphenous nerve on the medial side.

Figure 45-2 
Spread the subcutaneous tissue down to the capsule by use of a hemostat.



 Pass Second Spinal Needle

Pass the second spinal needle through this incision from outside-in, emerging from the meniscus adjacent to (∼5 mm) the first needle (
Fig. 45-3

). Needle placement dictates suture orientation (vertical or horizontal mattress). The vertical mattress configuration shows the least displacement under load.[8] Consider alternating femoral and tibial surface sutures.

Figure 45-3 
A second needle is introduced through this skin incision and across the tear.



 Secure Sutures

Use a working cannula through the anteromedial portal. Most graspers and instruments can be used through a 7-mm portal. Four options for securing sutures are as follows.


 Cable Loop Pull-through Technique (Johnson[4])

Pass cable loop through one needle (
Fig. 45-4

). Place absorbable suture with grasper through anterior portal into wire loop (
Fig. 45-5

). Pull suture through meniscus (
Fig. 45-6

). Repeat steps with other end of suture and other needle (
Fig. 45-7

). Withdraw needles and tie the single suture subcutaneously over the capsule (
Fig. 45-8

).

Figure 45-4 
Pass the cable loop through one needle.


Figure 45-5 
Place an absorbable suture with the grasper through the anterior portal into the wire loop.


Figure 45-6 
The cable loop is withdrawn out the needle with the suture.


Figure 45-7 
The procedure is repeated for the second needle, feeding the other end of the suture through the cable loop.


Figure 45-8 
A and B, Both needles are withdrawn from the incision. C, The single suture is tied down subcutaneously over the capsule.


If a cable loop is not available, the No. 0 PDS suture can be passed through the spinal needle out through the anteromedial portal, where a permanent suture can be tied to the PDS. The knot is then pulled through the meniscus. The process is repeated, resulting in a mattress suture.[16]


 Cable Loop Capture Technique (Cooper[1])

Place suture through one needle. Pass wire cable loop through other needle and capture end of suture material in joint (
Fig. 45-9

). Pull suture end out through meniscus and tie subcutaneously over capsule.

Figure 45-9 
The cable loop capture technique. See text.



 Mulberry Knot Technique (Warren[15])

Pass suture (No. 0 PDS) into needle, grasp inside joint, and pull out through anterior portal. Pass second suture (No. 0 PDS) into adjacent needle and repeat procedure.

Tie a knot (three or four throws) in the end of each suture, then pull knot back into joint so that knots lie against meniscus and maintain tear in reduced position. Use a cannula in the anterior portal to avoid entrapment of the knot in soft tissues. Tie adjacent sutures together over capsule (
Fig. 45-10

).

Figure 45-10 
A and B, The mulberry knot technique. See text.



 Dilator Knot Technique (Cooper[1])

Pass suture (No. 0 PDS) into needle, grasp inside joint, and pull out through anterior portal. Pass second suture (No. 0 PDS) into adjacent needle and repeat procedure. Use a cannula in the anterior portal to avoid entrapment of soft tissues between the sutures.

Tie a small knot (two throws) in one suture. Then tie adjacent sutures together outside portal. Pull suture with smaller knot (dilator knot) through meniscus (inside-out) ahead of the knot holding the two sutures together (
Fig. 45-11

). Now you can tie the single suture subcutaneously over the capsule.

Figure 45-11 
The dilator knot technique. See text.



Supplementary Options

Supplementary options to provide access to marrow-derived cells or factors are fibrin clot insertion[12] and microfracture in the notch.


Technical Considerations and Complications

       Stay anterior to biceps tendon on lateral side to avoid injury to peroneal nerve.
       Beware of posterior capsular entrapment, especially on medial side. Avoid excessive flexion during medial repairs. Use absorbable suture. For posterior horn tears of medial meniscus, tie suture with knee extended. This helps reduce meniscal tear to capsule and prevents entrapment of posterior capsule.
       Absorbable sutures should be used if suture placement requires penetration of the medial collateral ligament, semimembranosus, or popliteal tendon.
       The strength of vertical mattress repairs is ultimately limited by the strength of the suture material. Therefore, in tears with marginal healing ability (i.e., complex type, marginal vascularity, chronic tear), a nonabsorbable suture in vertical mattress orientation may enhance the likelihood of a successful repair.


Postoperative Considerations


Rehabilitation

Clinical studies demonstrate good results with accelerated rehabilitation[6]; however, few studies have used objective evaluation of meniscus healing (arthroscopy, magnetic resonance imaging). It is known that a tear may be only partially healed yet asymptomatic.[13] The long-term fate of such tears is unknown. Consider tailoring the postoperative protocol on the basis of the type of meniscal tear.


Authors’ Protocol

       A hinged double-upright brace is applied.
       Early range-of-motion exercise is prescribed.
       Flexion is limited to 90 degrees during the first 4 weeks to protect posterior horn repairs.
       Full weight bearing with the brace locked in full extension is allowed for bucket-handle and vertical longitudinal tears.
       For radial and complex tears (such as double longitudinal tears), only toe-touch weight bearing is recommended for the first 3 weeks and flexion is limited to 90 degrees during the first 4 weeks.
       Closed kinetic chain strengthening exercises are begun in the second week.
       Open the brace 0 to 40 degrees at 4 weeks.
       Weight bearing out of the brace is permitted at 4 to 6 weeks.
       Sport-specific activities are initiated at 6 to 8 weeks for further development of strength and proprioception.
       Running is allowed at 4 months.
       Return to full athletic participation is permitted by 5 months.
       Squatting and hyperflexion are avoided for up to 6 months.
       Concomitant ACL reconstruction: follow routine ACL rehabilitation protocol. Limit flexion and consider delayed weight bearing for radial and complex tears. No flexion limitations have occurred with use of this protocol.


Other Considerations

       Consider a less aggressive rehabilitation protocol if there is axial malalignment of the limb (e.g., repair of a medial meniscus in a varus knee) because the meniscus may be under higher loads.
       Consider the use of an “unloader” brace, which serves to shift the weight-bearing stresses to the opposite tibiofemoral compartment.


Complications


Neurovascular Injury

       Use transillumination
       Blunt dissection down to capsule


Failure of Meniscal Repair

       Poor selection
       Poor technique
       Oblique suture orientation
       Inadequate protection of repair
       Instability of knee
       Reinjury

PEARLS AND PITFALLS

       Preoperative counseling of the patient is important because compliance with rehabilitation is essential.
       The indications for lateral meniscal tears are broader because of better healing rates.
       Posterior horn tears of the medial meniscus are best considered unsuitable for outside-in repair owing to difficulty in achieving perpendicular needle placement across a far posterior tear.
       Position the patient such that the thigh protrudes over the table break if the table is flexed. This aids access to the posteromedial and posterolateral corners of the knee.
       To avoid nerve injury, stay anterior to the biceps tendon on the lateral side. On the medial side, work anterior to hamstrings for anterior third and posterior for middle third.
       A high anteromedial portal will help in visualization and repair of the lateral meniscus.
       Abrade surfaces of the meniscal tear and synovium adjacent to the tear with a rasp or 3.5-mm full-radius resector. Consider microfracture in the notch to provide access to marrow-derived mesenchymal cells.
       Transillumination minimizes injury to cutaneous nerves and vessels.
       Use a probe to apply counterpressure against the meniscus when needles are inserted.
       Use vertical mattress configuration.
       Prescribe early range of motion. Limit flexion and weight bearing for radial and complex tears.


Results

Results of meniscal repair by the outside-in technique are shown in
Table 45-1

.


Table 45-1 
 — Results of Outside-In Meniscal Repair
Author No. of Repairs Evaluation Followup Outcome
Morgan et al[7] (1991) 74 (of 353 repaired menisci) Second-look arthroscopy   84% successful outcome (62/74)
65% healed (48/74)
19% partially healed (14/74)
16% failure rate (12/74)
        Increased failure in ACL-deficient knees and posterior horn tears of medial meniscus
Rodeo and Warren[11] (1996) 90 Computed tomographic arthrography Minimum of 2 years 86% successful outcome (partial or complete healing with minimum symptoms)
        Increased failure in unstable knees
van Trommel et al[13] (1998) 51 Arthroscopy, arthrography, magnetic resonance imaging, or combination Average of 15 months (range: 3-80) 45% complete healing
        32% partial healing
        24% no healing
        Significantly lower healing for tears in posterior horn of medial meniscus

ACL, anterior cruciate ligament.

In the Hospital for Special Surgery experience,[11] an 86% successful outcome was reported: 67% asymptomatic with objective evidence for complete healing, 19% minimally symptomatic with objective evidence for partial healing, and 14% failure rate (significant symptoms or objective evidence of failure to heal). The failure rate was based on knee stability: stable knees, 15% (5 of 33); unstable knees, 38% (5 of 13); and concomitant ACL reconstruction, 5% (2 of 38). Fibrin clot was used in 17 repairs with a failure rate of 35% (6 of 17) due to unrepaired ACL insufficiency (3) and complex tears in the avascular zone of the meniscus (3). Complications (3%) included saphenous nerve entrapment (1), thrombophlebitis (1), and infection (1).

In the study of Morgan et al,[7] the majority of failures occurred in posterior horn tears of the medial meniscus (11 of 12 failures), and all failures occurred in ACL-deficient knees. Healing was complete with disappearance of the absorbable suture in approximately 4 months. These authors were among the first to point out that incompletely healed menisci can be clinically asymptomatic.

van Trommel et al[13] described different regional healing rates with the outside-in technique. A significantly lower healing rate was reported for tears in the posterior horn of the medial meniscus, which was thought to be due to the obliquity of the sutures in this region. It can be difficult to place the needles perpendicular to the tear in the far posterior zone of the meniscus, resulting in oblique suture placement. The inside-out or all-inside technique should be considered for repair of tears in the posterior horn of the medial meniscus.





This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More