Summary

A technical note presenting the Arthrex LoopLoc Knotless Implant for improved hip capsular closure following hip arthroscopy.

Abstract

Background

Hip capsulotomy is routinely performed in arthroscopic procedures to achieve adequate intra-articular exposure and visualization. However, subsequent capsular insufficiency can lead to joint instability and poor function outcomes after primary hip arthroscopy. This can be avoided with effective closure of the hip capsule. Prior literature has recommended 3-suture constructs and the Quebec City Slider (QCS) technique for closure of the hip capsule. Further, a recent article described a technique for periportal capsulotomy closure to repair or plicate the hip capsule in hypermobile patients. These techniques introduce stacks of knots, variability in knot strength among surgeons and overall weak constructs. This technical note describes a new knotless method for closing the hip capsule.

Purpose

To present and recommend a new method for arthroscopic capsular closure or plication using the Arthrex LoopLoc Knotless Implant.

Methods

Once all arthroscopic procedures in the central compartment are complete, capsular closure is begun with the hip in 45 degrees of flexion. First, a passing suture is passed through the acetabular and femoral limbs of the capsular tissue. This will later be used to pass the knotless capsular closure device (LoopLoc, Arthrex, Naples, FL, USA). This step should be repeated as many times as necessary as per the surgeon’s preference. The lead author prefers to use 2-3 sutures for a standard interporal capsulotomy closure. Passing sutures not in use may be “parked” for later use in the distal anterolateral accessory (DALA) portal. Through the mid-anterior portal both ends of the passing suture can be used to pass the initial interlocking loop of the knotless device. Once this is passed, the free limb of the other interlocking loop is passed through the loop and through a flag which is fed through a knotless mechanism. The tensioning sutures are then evened and clamped, after which the center of the interlocking loop is guided into the center of the capsular repair.
Prior to tensioning, a suture grasper is used to temporarily interlock each loop of the device. This ensures that the center of the interlocking loop will remain in the center of the capsular limbs while still permitting tensioning. Once this is complete, initial tensioning begins by alternate pulls of approximately 2cm of each limb of suture until the knotless mechanism rests on top of the capsular repair. At this point, the looped grasper may be removed. Then, both tensioning free limbs are passed through a closed suture cutter which is placed on top of the capsule. Each limb may be individually tensioned to the surgeon’s preference. Once final tensioning is complete, closed suture cutter is used to cut the suture, leaving a 1-2mm tail. The same step can be applied for additional LoopLoc implants as needed to complete closure of the hip capsule.

Results

The LoopLoc Knotless Implant is an excellent alternative to hip capsular closure with traditional sutures that requires a knot to be tied outside of the cannula. Some of the advantages of the knotless implant include less steep learning curve, no knot stacks, which minimizes prominence of permanent sutures, increased strength of the construct, low variability of knot strength among different surgeons, which means consistent strength of the repair as it is not dependent on knots, and finally less intraoperative time required for capsular closure. Further, an Arthrex Orthopedic Research Department biomechanical evaluation showed that the LoopLoc Knotless Implant allowed a mean ultimate load of 214 ± 27 N, compared to 153 ± 25 N for #2 Vicryl suture constructs.

Conclusion

Capsulotomy followed by appropriate capsular repair and closure is critical for restoring biomechanical properties of the hip, ensuring high survivorship and improving functional outcomes. We recommend the new Arthrex LoopLoc Knotless Implant which could further ease and strengthen the hip capsular closure following hip arthroscopy to reduce post-operative instability and complications.