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Paper text:
three portals are used in this technique : a standard anteromedial portal , a standard anterolateral portal , and an extreme far anteromedial portal ( fig .
this portal is located 1 cm above the lateral joint line and 1 cm lateral to the margin of the patellar tendon .
this portal provides easy access for a special instrument to the anterior horn of the lateral meniscus .
this portal is located approximately 1 cm above the medial joint line and just medial to the margin of the patellar tendon and provides viewing of the anterior horn of the lateral meniscus .
to avoid collision of arthroscopic instruments , this portal is more closer to the patella tendon than the normal standard anteromedial portal .
the extreme far anteromedial portal is created as another working portal 3 cm medial to the margin of the patella tendon .
this portal is located 1 cm above the medial joint line and nearly anterior to the medial edge of the medial femoral condyle .
this portal is used for the removal of the unstable inferior leaf in the anterior horn of the lateral meniscus .
after diagnostic arthroscopy , a careful estimation of the depth and extent of the cleft and stability of the superior and inferior leaves is made with the use of a probe under the position of figure " 4 " . through the low anterolateral portal
, a small skin hook retractor is inserted to reach the superior leaf of the anterior horn .
this portal allows optimal and stable handling of the dominant superior leaf and viewing of the unstable inferior leaf ( fig .
is then excised with a 90 rotary punch through the extreme far anteromedial portal ( fig .
a motorized shaver ( linvatec , largo , fl , usa ) is used to smooth the remnant rim of the meniscus ( fig .
a small skin hook retractor is used to provide firm and stable meniscal retraction during postural or instrumental changes .
the dominant superior leaf can be damaged and detached with excessive or sudden retraction force .
horizontal tears of the meniscus are associated with degenerative changes in the meniscal tissue1 ) . until recently , the preferred treatment for meniscal injury has been partial meniscectomy or subtotal meniscectomy . for degenerative tears
the goal of careful partial meniscectomy of the horizontal tear is to preserve meniscal functions3 ) .
it is difficult to reach the inferior leaf of the anterior half of the meniscus to perform proper resection of the meniscus in tears extending to the anterior portion of the meniscus . and
it is difficult to decide how much of the meniscus should be resected in the case of deep - seated horizontal tears because it often extends into the capsular junction in multiple directions .
various methods for the treatment of a horizontal tear in the anterior horn of the meniscus have been proposed and described .
kim et al.4 ) described the inframeniscal portal technique for horizontal tears of the meniscus .
it proved to be an effective method for treating horizontal tears of the meniscus ; however , the disadvantage of this technique is the complication of impending synovial fistula .
kim and park5 ) described an arthroscopic technique of partial meniscectomy for horizontal tears of the meniscus using 3 portals .
this technique is safe and simple , and does not cause injury to the soft tissues .
however , it does not allow optimal handling of the dominant superior leaf for excision of the unstable inferior leaf of the anterior horn in horizontal tears of the meniscus .
meniscal retraction using a probe does not provide enough stability because of probe slippage during the arthroscopic procedure .
we have described a technique of arthroscopic partial meniscectomy using 3 portals and a small skin hook retractor for horizontal meniscal tears that involve the anterior portion of the lateral meniscus .
our technique is a useful method because it allows optimal and stable handling of the dominant superior leaf and viewing of the unstable inferior leaf . and surgeons can attempt resection of the margins of the meniscus more easily because the stable retraction is helpful in identifying the shape and extent of deep - seated horizontal tears .
we introduce a new arthroscopic partial meniscectomy technique using a three portals and a small skin hook retractor to remove unstable inferior leaf in horizontal meniscal tear that involved the anterior portion of the lateral meniscus . 
 the patient is positioned for a standard knee arthroscopy . 
 after careful estimation of the depth and extent of the cleft and stability of the superior and inferior leaves is done through the standard anteromedial portal , a small skin hook retractor is inserted through the standard anterolateral portal to raise the dominant superior leaf of anterior horn , then the unstable inferior leaf is excised with a 90 rotary punch and a motorized shaver through the extreme far anteromedial portal . 
 this technique is useful method to remove unstable inferior leaf of anterior horn of lateral meniscus which is difficult to remove with a standard technique .