///

Anterior shoulder stabilisation using arthroscopically introduced bone block and Arthrex TightRopes-RT

    Overview

    Learn the Anterior shoulder stabilisation using arthroscopically introduced bone block and Arthrex TightRopes-RT surgical technique with step by step instructions on OrthOracle. Our e-learning platform contains high resolution images and a certified CME of the Anterior shoulder stabilisation using arthroscopically introduced bone block and Arthrex TightRopes-RT surgical procedure.

    Anterior shoulder instability with concomitant bone loss from the glenoid and/or humeral head represents a surgical challenge.
    Critical glenoid bone loss of greater than 20%-25% is a recognised cause of failed arthroscopic Bankart repair.
    A ‘subcritical’ bone loss greater than 13.5% has also been proposed as clinically significant and has been associated with an unacceptable functional outcome independent of redislocation.
    In most cases these bone defects are bipolar lesions with concomitant bone loss from the glenoid and humeral side and usually can be managed with glenoid-based surgery.
    The Latarjet procedure has been the workhorse for these difficult cases. However, it offers a nonanatomic reconstruction and its arthroscopic version although is gaining increasing popularity, is associated with a high complication rate and a steep learning curve.
    During the Latarjet procedure 2 metal screws are usually used for the fixation of the coracoid graft on the glenoid. However hardware-related complications are the most common cause for repeat surgery. These include screw migration, loosening, or breakage and hardware irritation.
    Boileau has reported a 91% union rate for arthroscopic Latarjet using a single suture button fixation device. The construct is secured with a sliding locking knot.
    Anterior bone block procedures including tricortical iliac crest graft and distal tibial allograft have also been described for cases with significant bone loss with good results.
    This an arthroscopic technique that allows a tricortical iliac crest graft to be introduced through the rotator interval on the anterior glenoid neck. The graft is positioned flush with the bone using a posterior glenoid guide and secured in place with 2 Tightropes-RT (Arthrex, Naples, FL) which are adjustable length-loop devices and tensioned between cortical buttons with a suture tensioner. The fixation is knotless.
    A biomechanical study has shown that the median ultimate failure load after coracoid fixation with 2 metal screws was 202 N (range, 95-300 N).
    Another study has shown that the ultimate failure strength of the Arthrex knotless ACL TightRope-RT as a construct was 859 N, considerably higher than the strength required for a Latarjet procedure.

    Indications

    I consider arthroscopic reconstruction of the glenoid with iliac crest bone graft in cases with significant glenoid bone deficiency, in bipolar lesions with bone loss from the anterior glenoid and the humeral head and in some revision cases.
    As significant glenoid bone loss we consider bone deficiency of 20% or between 10-20% in young patients, involved in competitive and or contact sports and in the presence of hyperlaxity.
    Patients usually have an MRI arthrogram but routinely all patients have a 3D-CT of the shoulder with digital subtraction of the humeral head providing an en face sagittal view of the glenoid. The percentage of glenoid bone loss can be calculated by modeling the inferior aspect of the intact glenoid as a true circle.
    Advantages
    Anatomic reconstruction of the glenoid. The integrity of the subscapularis is not affected.
    The posterior glenoid guide allows optimal placement of the bone block with the TightRope fixation devices parallel to the glenoid.
    No rigid cannula is used for the insertion of the graft through the rotator interval, allowing a bigger sized graft to be used for reconstructing the anterior glenoid.
    The knotless TightRope devices tensioned between metallic buttons offer a self-securing method that provides good fixation.
    The all-arthroscopic approach offers better cosmesis, faster rehabilitation, and return to preinjury activity levels.
    Disadvantages
    Donor-site morbidity (iliac crest).
    Advanced arthroscopic skills required.

    Setup

    Operation – 1

    Harvesting of the tricortical iliac crest bone graft
    The procedure is performed in the supine position under general anaesthetic with a small sandbag under the the ipsilateral ischial tuberosity to facilitate access to the anterior iliac crest.

    A 4-5 cm skin incision parallel to the iliac crest, 2-3 cm behind the anterior superior iliac spine to avoid injury to the lateral femoral cutaneous nerve.
    The incision is carried down to the fascia overlying the iliac crest and subperiosteal dissection is performed using the electrocautery for haemostasis.
    The outer and inner table of the bone is exposed 2 cm distally.


    Blunt retractors are used to maintain the exposure.

    The approximate size of the bone graft is 2.5 cm x 1 cm x 1 cm.

    An oscillating saw is used for parallel transverse cuts 2.5 cm apart and almost 2 cm deep.
    Starting at the outer table curved osteotomes are used to complete the osteotomy and harvest the tricortical bone graft.

    The measurements of the graft are
    2.5 cm length
    1 cm width
    1 cm height .
    If needed the graft can be further contoured using the saw.

    Be careful ‘not to drop the graft on the floor’ !


    Although the size of the graft can be customized depending on the case, it can technically be more difficult to introduce arthroscopically a bone block longer than 2.5 cm.


    The inner table surface tends to be concave (blue colouring) and will be used on the articular side to extend the length of the native glenoid.
    The bone graft will be positioned so that the cancellous surface will “sit” on the anterior glenoid neck.

    After harvesting the graft the bony surfaces are covered with bone wax to minimise bleeding .

    The wound is closed in layers and the fascia is repaired minimizing postoperative pain from the graft site.

    The wound is infiltrated with local anaesthetic (20 mls of 0.5% Marcaine).
    No drains are used.

    Preparation of the bone graft
    Two 2-mm drill holes using K-wires are made 10 mm apart and 5 mm from the “articular”edge of the graft.


    The K-wire enters through the cortex and exits the cancellous side of the bone graft.
    The holes created correspond to the distance of the cannulated drills that will be placed in the glenoid neck.

    The holes created correspond to the distance of the 2.4-mm cannulated drills that will be introduced through the glenoid using the posterior glenoid guide.

    Posterior drill guide
    The guide consists of two components.
    The hook end is introduced parallel to the face of of the glenoid and the tip is rotated once past over the anterior glenoid edge.

    The second component allows 2 drill holes to be drilled through the glenoid 10mm apart.
    Two 2.4-mm cannulated drills are used for this purpose.

    The Glenoid guide has an offset of 7 mm.

    2.4-mm cannulated drill

    Operation – 2

    2.4-mm cannulated drill with the inner core removed.

    The aim is to place the bone block level with the bone (and not the articular cartilage) minimising the contact pressure on the humeral head and possibly reducing the risk of developing arthritic changes in the future.
    The guide provides a 7-mm offset taking into account a 2-mm average cartilage thickness and the 5 mm between the drill hole on the block and lateral (articular) side of the graft.

    Knotless TightRope-RT
    The TightRope-RT (Arthrex) uses an innovative locking system eliminating the need for knots resulting in very high ultimate loads.
    A metal button is already incorporated in one end of the TightRope system.

    The length of the system can be adjusted by pulling the tensioning strands.

    A. Tensioning strands
    By pulling on the the white strands the length of the loop can be adjusted.




    Dog-Bone buttons (Arthrex, Naples, FL)

    A metal button is already incorporated in one end of the TightRope system and on the other end a Dog-Bone button (Arthrex, Naples, FL) will be loaded so that the adjustable tightrope system will be suspended between two cortices: the anterior cortex of the iliac crest graft and the posterior cortex of the glenoid neck.

    Plastic model demonstrating the position of the bone block.

    Shoulder arthroscopy
    Following harvesting of the iliac crest graft the patient is placed in a beach chair position.
    The patient undergoes an interscalene brachial plexus block (supplemented by general anaesthesia).
    The whole of the shoulder, arm and hand of is prepared with chlorhexidine in spirit and draped in the standard fashion..
    The operative arm is placed in a Trimano support that can hold the patient’s arm in any desired position during surgery.
    The shoulder is placed in 45 degrees of flexion and neutral rotation. The elbow is placed at 90 of flexion. A 30 degree arthroscope is used.
    The patient’s systolic blood pressure is preferably maintained below 100 mmHg and an arthroscopic pump infuses normal saline at 50 mmHg.

    I often use skin staples to secure the drape in place and ensure good exposure.

    With the exemption of the posterior portal, all other portals are created with an outside-in technique using a needle.
    A. Posterior portal at the ‘soft-spot’ 2.5 cm medially and distally to the posterolateral corner of the acromion.
    B. Anterior portal lateral to the coracoid process and through the rotator interval. The trajectory of the needle is from superior to inferior allowing access to the inferior glenoid. This orientation allows delivery of the iliac crest bone graft to the anterior glenoid neck area.
    C. Anterolateral portal 1 cm inferior and lateral to the anterolateral edge of the acromion
    D. Posterolateral portal 2-3 cm lateral to the posterior portal and 2-3 cm inferior to the posterolateral corner of the acromion.

    Posterior ‘standard’ portal.

    Palpating the coracoid anteriorly helps with the orientation.

    A 30 degree arthroscope is introduced into the glenohumeral joint and a systematic inspection of the joint is performed.

    A. Hill-Sacks lesion humeral head
    B. Glenoid

    Significant Hill-Sachs lesion that engages on abduction – external rotation.
    There is also bone loss at the anterior glenoid with a bony fragment displaced medial to the anterior edge.

    Preparation of the glenoid
    A. Anterior edge of glenoid
    B. Labrum

    A 90 degree radiofrequency wand (Apollo RF) is introduced through the anterior portal and the anterior labrum is completely elevated (but preserved) to expose the glenoid defect.

    A bone fragment (‘bony Bankart’) is identified medial to the anterior edge of the glenoid.

    The bony fragment is exposed using the radio frequency device.

    A. Humeral head
    B. Labrum
    C. Subscapularis muscle fibers
    D. Bony bankart

    The bone fragment has been exposed, the labrum elevated and the underlying muscle fibres of the subscapularis can be seen.
    The labrum is preserved and will be reattached to the anterior glenoid edge at the end of the procedure placing the iliac crest graft in an extracapsular position.
    The Bankart repair will provide additional stability, improved proprioception and the interposed tissue between the iliac crest graft and the humeral head may prevent or delay the development of arthritic changes.

    An arthroscopic burr (4 mm) is introduced through the anterior portal.

    The bony Bankart is debrided to provide the necessary space for the iliac crest bone graft.
    The aim is to produce a flat bed on the anterior glenoid neck for the bone graft.

    A. Coracoacromial ligament
    B. Upper border of subscapularis
    C. Muscle fibres of deltoid

    The camera is looking upwards towards the rotator interval.
    The skin stab incision at the anterior portal in extended to approximately 1.5cm in length to allow the introduction of the iliac crest bone graft.
    At the same time the soft tissues at the rotator interval are debrided to create the pathway for the passage of the bone block.
    Useful landmarks are
    upper border of the subscapularis
    the anterior border of the CA ligament

    A needle holder can be used to spread the deltoid muscle fibres and rotator interval tissue.

    Operation – 3

    This help to enlarge the opening and facilitate the introduction of the bone graft through the rotator interval down to the anterior glenoid neck.
    No cannulas are used for this procedure.

    The anterolateral portal is established.

    A. Upper border of subscapularis
    The needle is introduced just lateral to the anterolateral corner of the acromion and in parallel with the upper border of the subscapularis.

    Whilst viewing from the posterior portal, aSutureLasso SD 45, Curve Right (for a Right shoulder) is introduced through the anterior portal.

    The SutureLasso comes preloaded with a Nitinol Wire Loop used to shuttle suture through soft tissue.

    After the tip is passed through the anteroinferior labrum approximately at 4-o’clock, the loop is deployed and retrieved through the anterolateral portal with a Suture Retriever.

    The tail of a LabralTape is placed in the loop, and the opposite end of the loop is pulled, delivering the tape through the labrum.

    Both strands of the LabralTape are retrieved through the anterolateral portal using a TapeRetreiver.
    The roller pin in the upper jaw of the TapeRetreiver allows Tapes to slide freely.

    A. Glenoid
    B. Humeral head
    C. Labrum

    The Labral Tapes are pulled laterally helping to retract the labrum and capsule laterally facilitating the introduction of the bone graft on the glenoid neck.
    After fixation of the bone graft on the anterior glenoid the LabralTapes will be loaded onto PushLock anchor for the final labral repair.



    Lateral pull on the LabralTapes through the anterolateral portal.



    A. BioCompositeTM PushLock, 2.9 mm
    B. LabralTape

    The arthroscope is moved to the anterolateral portal.

    A flat glenoid rasp is introduced through the anterior (rotator interval) portal.

    A. Humeral head
    B. Glenoid
    C. Anterior glenoid neck

    viewing portal: anterolateral
    The glenoid neck is prepared to a flat surface so that there will be good ‘flat on flat’ contact with the iliac crest bone graft.

    This can also be achieved with the arthroscopic burr as seen here or with the motorised PoweRasp as demonstrated on the attached video.


    A 2.9-mm PushLock anchor (Arthrex) hole is drilled at the 3-o’clock position.
    The hole is drilled before the placement of the TightRopes through the glenoid so to avoid potential compromise of the suture fixation during drilling.
    This step can be performed at an earlier stage -usually when viewing through the posterior portal- but often there is some blood oozing from the drill hole affecting visualisation and therefore I tend to perform this step as late as possible.

    A. Glenoid
    B. Neck of glenoid

    The spear is inserted through the anterior portal and placed onto the glenoid rim.

    The drill is fully advanced through the spear until its collar makes contact with the spear’s handle.

    Viewing through the anterolateral portal toward the posterior aspect of the glenohumeral joint.

    A. Glenoid
    B. Posterior capsule
    C. Hill-Sachs lesion on humeral head
    D. Loose body
    Alternatively, the posterior aspect of the joint may be visualised through the anterior portal as seen on the attached video.

    The posterolateral portal (D) is created.
    A spinal needle is introduced approximately 2cm lateral to the standard posterior portal (A).

    The needle is flush to the glenoid at the level of the equator.
    The posterior glenoid guide will follow the trajectory of the spinal needle parallel to the glenoid surface.

    The opening at the posterior capsule is slightly enlarged with the radiofrequency wand.

    Posterior portal (A): the skin incision is enlarged to approximately 1.5 cm to allow the introduction of the second component of the glenoid guide.

    A needle holder is used to spread the deltoid and infraspinatus muscle fibres aiming toward the area of the posterior glenoid neck.

    Operation – 4

    This will allow the glenoid guide to reach the posterior glenoid neck avoiding interposition of muscle fibres.


    The hook end of the posterior glenoid guide is introduced through the posterolateral portal (D).

    The guide is introduced parallel to the glenoid surface.

    The hook of the guide is rotated around the anterior glenoid.

    A. Drill hole for Pushlock anchor at 3-o’clock

    The tip is anchored 7 mm medially to the glenoid surface at approximately the 4-o’clock position.


    The second component of the posterior guide is assembled posteriorly.


    It is slid down to the posterior glenoid neck, where it is secured firmly by tightening the small screw at the side of the guide.


    Two 2.4-mm cannulated drills are introduced through the guide (10 mm apart) and advanced with power to the anterior glenoid neck under direct vision.

    Viewing portal: anterolateral
    The superior 2.4-mm cannulated drill introduced first.

    Followed by the second cannulated drill.

    Both cannulated drills in place on the anterior glenoid neck 10 mm apart.

    Both components of the glenoid guide can now be removed leaving the cannulated drills in situ.

    The glenoid guide has been removed and the cannulated drills can be seen on the anterior glenoid neck 7 mm medial to the glenoid face.

    The central core of the superior cannulated drill is unscrewed.


    A FiberStick (Arthrex) is passed through the cannulated drill.


    FiberStick is #2 FiberWire with the first 12 inches stiffened to allow easy advancement through cannulated instruments.
    FiberSticks come with a thin plastic tube which protects the stiffened suture until use.
    TigerStick is similar to FiberStick but white with a black stripe in the suture, making suture identification easier.

    The plastic tube has been removed revealing the stiff “waxed” end of the FiberStick.

    TigerStick

    On the screen of the arthroscopy stack the stiff end of the FiberStick can be seen inside the joint.

    A. Glenoid
    B. LabralTapes through the anterior labrum used at this stage to pull the soft tissues laterally and create ‘working space’ at the area .

    Fiberstick through the superior cannulated drill
    (viewing portal: anterolateral).

    The Fiberstick is captured by an arthroscopic grasper that is introduced through the anterior portal.

    Operation – 5

    The Fiberstick is brought out through the anterior portal.

    The superior cannulated drill is removed.


    The Fiberstick is used as a leading suture for the passage of the TightRope-RT through the bone tunnel in the glenoid.

    I use a bowline knot to attach the TightRope.

    By pulling on the Fiberstick the TightRope is passed through the glenoid and brought out anteriorly through the anterior portal.

    I use the Pushlock eyelet to pass the Fiberstick through the corresponding hole of the tricortical iliac crest graft.


    Pulling on the Fiberstick will bring the TightRope through the bone graft.
    The 2-mm drill hole on the bone graft is just large enough to allow the loops of the TightRope to pass through.


    A Dog-Bone button is attached to the 2 loops of the TightRope.

    I keep the superior TightRope system ‘under tension’ anteriorly and posteriorly to avoid tangling with the second TightRope.

    The same process is repeated for the second TightRope.

    2 TightRope-RT
    have been introduced from posteriorly
    passing through the glenoid
    exiting through the enlarged anterior portal
    passing through the coresponding drill holes of the iliac crest graft
    Dog-Bone buttons loaded on the cortical side of bone graft
    No cannulas are used for this procedure mainly because the size of available cannulas would limit the size of the bone graft used.
    A size 12 Passport cannula could be an option though if required.

    The arthroscope is moved to the posterolateral portal

    The bone graft is controlled with a Alice clamp anteriorly.
    Tension is kept on the TightRopes posteriorly ensuring that we know at all times which is the superior and which is the inferior.


    By pushing anteriorly and pulling posteriorly the bone graft is introduced into the anterior glenoid.

    The clamp is released as the bone graft reaches the anterior glenoid.
    On the screen of the arthroscopy stack, the bone graft can be seen having reached the anterior glenoid.
    The graft is now ‘pushed’ toward its position on the neck of the glenoid using a paddle retractor.
    I prefer using this instrument to manipulate the graft as it has a broad smooth tip.

    A. Anterior glenoid
    B. Humeral head
    C. Bone graft

    The paddle retractor is pushing the bone graft medially toward the neck of the anterior glenoid.
    At the same time a lateral pull on the LabralTapes (through the anterolateral portal) retracts the labrum and capsule out of the way to help positioning the bone graft.


    Tensioning of TightRopes
    The TightRopes are progressively tensioned by pulling on the tensioning strands in an alternating fashion bringing the posterior buttons on the cortex of the posterior glenoid neck.

    At this stage I try again to spread apart the muscle fibres posteriorly to allow the button to reach the bone surface of the posterior glenoid neck without soft tissue interposition.

    The same process is repeated with the second TightRope.


    Further compression of the graft on the anterior glenoid neck is achieved with the suture tensioner, which is applied sequentially to each Tight- Rope first at 50 N and finally at 100 N.

    TightRope fully tensioned at 100N.

    After tensioning the TightRopes the lengths of the tensioning strands are compared: they should be of equal length; otherwise it would indicate soft tissue interposition (in the ‘shorter’ one). In this case i would reapply the suture tensioner before eventually cutting the tensioning strands with the arthroscopic cutters.
    The TightRopes are self-locking; therefore, no knots are required.

    Operation – 6

    A. Humeral head
    B. Glenoid
    C. Bone graft
    D. Drill hole for Pushlock anchor
    (viewing portal: anterolateral)
    The final position of the graft is inspected to ensure that the graft is flush with the glenoid.
    If there are overhangs these can be trimmed with the arthroscopic burr.

    The final stage is a Bankart repair.
    Pushlock anchors are used and the technique is described in another Orthoracle chapter

    (viewing portal: anterolateral)

    A. Humeral head
    B. Glenoid
    C. Bone graft
    D. Interposed labrum/capsule

    (viewing portal: posterior)
    A. Humeral head
    B. Glenoid
    C. Bankart repair

    Subcuticular 3-0 Monocryl used for the anterior and posterior portal only.

    The port sites are covered with dressings and finally a Polishing is applied with a body belt.

    Post Operative

    Post-operatively we follow the same protocol as for arthroscopic anterior stabilisation
    0-3 weeks
    Sling for 3 weeks
    Teach axillary hygiene
    Active flexion in supine as comfortable (to be determined by therapist in appointment1)
    Active external rotation in 0° abduction as comfortable (to be determined by therapist in appointment1)
    scapular control during elevation and lateral rotation
    Isometric internal and external rotation exercises
    Proprioceptive exercises (minimal weight bearing below 90 degrees)
    Teach postural awareness
    Core stability exercises (as appropriate)
    Encourage global exercise (as appropriate)
    Do not force or stretch
    No combined abduction & external rotation

    3-6 weeks
    Wean off sling
    Continue proprioceptive exercises
    Progress to full active ROM
    Do not force or stretch
    No combined abduction & external rotation

    6-12 weeks
    Regain scapula & glenohumeral stability working for shoulder joint control rather than range
    Progress strength through range
    Increase proprioception through open & closed chain exercise
    Progress core stability exercises
    Treat posterior tightness, if required
    Incorporate sports-specific rehabilitation
    Plyometrics training

    1Use the patients perception and apprehension to determine range of movement

    Recommended Reading

    Reference

    • orthoracle.com

    Tags:

    You might be interested in

    Dark mode powered by Night Eye