Issue: June 2011
June 01, 2011
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Bone loss in shoulder instability: Part 2

Issue: June 2011
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Round Tablediscussion of the current concepts and technological advances in shoulder instability surgery for cases with bone loss. To read part 1 of this Round Table, see the May 2011 issue of Orthopedics Today (page 50).

– William N. Levine, MD
Moderator

Round Table Participants

Moderator

William N. Levine, MDWilliam N. Levine, MD
Columbia University Medical Center New York, N.Y.

Christopher S. Ahmad, MDChristopher S. Ahmad, MD
Columbia University Medical Center New York, N.Y.

Augustus D. Mazzocca, MS, MDAugustus D. Mazzocca, MS, MD
New England Musculoskeletal Institute University of Connecticut Health Center Farmington, Conn.

Edwin R. Cadet, MDEdwin R. Cadet, MD
Columbia University College of Physicians and Surgeons New York-Presbyterian/Columbia University Medical Center New York, N.Y.

Matthew T. Provencher, MD, CDR, MC, USNMatthew T. Provencher, MD, CDR, MC, USN
Naval Medical Center San Diego San Diego, Calif.

T. Bradley Edwards, MDT. Bradley Edwards, MD
Fondren Orthopedic Group Houston, Texas

William N. Levine, MD: How would you manage a 21-year-old, right-hand dominant man with an acute bony Bankart involving 20% of the glenoid? Do you repair these injuries arthroscopically and, if so, share some technical pearls? When would you consider open reduction and internal fixation (ORIF)? Is there an indication for a coracoid transfer in this scenario?

Christopher S. Ahmad, MD: An evaluation of an acute bony Bankart requires a CT scan and the fragment should be assessed for size, location and comminution. Many fractures can be managed arthroscopically. The technique involves diagnostic arthroscopy, which often identifies the fracture with the capsulolabral complex attached to the fracture. Above and below the fracture, the capsulolabral complex is detached from the glenoid. One method of arthroscopic repair is to perform a standard suture anchor repair of the labrum in the area above and below the fracture. This reduces the bony fragment. Then arthroscopic assistance can achieve percutaneous screw fixation to the fragment, if the fragment is large enough. This allows for a strong fixation and accelerated rehabilitation. In the cases of a smaller bony Bankart lesion, we prefer a double row type labral repair that compresses the bone fragment against its anatomic detachment site. The technique is similar to a double row rotator cuff repair (Figure 1).

Shown here is a double row type labral repair that compresses the bone fragment against its anatomic detachment site.
Figure 1. Shown here is a double row type labral repair that compresses the bone fragment against its anatomic detachment site.

Image: Columbia University Center for Shoulder, Elbow and Sports Medicine

Edwin R. Cadet, MD: In this scenario, I repair these injuries arthroscopically. If the fragment is 20% of the glenoid base, I believe that screw fixation may compromise the quality of the fragment, as the bone piece is usually 4 mm to 5 mm. I use a double-row technique, as described by Millett and Kim. In general, it is my practice to perform shoulder instability in the beach chair position; however, many use the lateral decubitus position. I use an anterior portal just above the subscapularis and a superior, anterolateral portal just above the long head of the biceps tendon as it enters the glenohumeral joint.

I mobilize the osseous Bankart lesion and visualize the anterior neck of the glenoid from this portal while bringing my instruments through the anterior portal. The medial row anchor is usually placed at the midpoint of the osseous fragment, which is usually around 4:00 to 4:30. I switch to the posterior viewing portal, and I use a 70° scope to visualize placement of the suture passer medial to the bone fragment. The superior, anterolateral portal can be used to retrieve your sutures, or you can pass the suture passer percutaneously and retrieve the nitinol wire or suture from the anterior portal. Other one-pass suture passers (Transporter, Smith & Nephew) can facilitate suture passing and management.

The medial row is not tied, and the lateral row is placed on the face of the glenoid. By not tying the medial row, you can tension sutures and, ultimately, the compression across the bone fragment. The capsulolabral complex that is inferior to the bone fragment is fixed to the glenoid face at the 5:30 position with a suture anchor (higher if you want more of shift depending on exam under anesthesia) and tied in either a simple or mattress technique. I use a 45° suture passer from the anterior portal to accomplish this. I usually place the most inferior anchor using percutaneous techniques, as it allows low, perpendicular placement of the anchor on the face of the glenoid without the constraints of the cannula. A knotless anchor is used for the lateral row of the previously placed medial anchor to provide compression across the bone fragment (similar to the “suture-bridge” construct for rotator cuff repairs). I frequently use the Arthrex 2.9 PEEK Pushlock anchor. This can be placed from the anterior portal. The number of medial row anchors will depend on the size of the osseous lesion. You can also use a double-loaded medial row anchor, pass four suture limbs medial to the osseous fragment (two inferior and two superior). This provides three-point fixation of the fragment by placing another knotless anchor superior to the previous anchor. I will then use one more anchor superior to the last knotless anchor to incorporate the remaining capsulolabral tissue of the repair. A minimum of three anchors are used to complete the repair.

T. Bradley Edwards, MD: I would address this patient with a Latarjet procedure primarily.

Augustus D. Mazzocca, MS, MD: As Drs. Ahmad and Cadet have suggested, we would attempt to repair using the Millet technique where we place suture tack anchors arthroscopically on the medial aspect, go through the bony Bankart with the sutures, and then take push lock anchors over the side. We do this with two screws, so the technical pearl for the Millet technique is that we will place an anchor right at the most inferior aspect of the bony Bankart and repair the capsulolabral complex there to secure it. Then we reduce the bony Bankart and put our two medial anchors in and individually place them over the glenoid using suture tacks. We have found this arthroscopic management style very successful. However in some cases where there is significant comminution or it is not reducing properly, we will change to an open procedure for internal fixation. Indications for a coracoid transfer in this scenario would be a significant amount of comminution when attempting to reduce the bony Bankart or if the fragment is split multiple times. We would allow for 1-1½ hours of time for this arthroscopic procedure and if it was still not coming together and we were not making good progress after that amount of time, we would switch to an open procedure.

Matthew T. Provencher, MD, CDR MC, USN: An acute bony Bankart in a young patient may be fixed either arthroscopically or open. One potential pitfall for either repair is that a 20% bone injury is only about a 5- to 7-mm piece of bone anterior to posterior. Although it may look like fracture screws (2.7- or 3.5-mm screws) may easily repair the defect, the bone may fracture or splinter when performing this repair. Smaller screws (2.7 mm or smaller) may prevent this complication, or a hybrid construct with screws or a pure suture anchor repair. A pearl with a suture anchor repair for an open performed case is to repair and tension the bone fragment with suture around and underneath (medial) to the fragment.

Arthroscopic repairs are accomplished in a similar fashion, although various techniques may prevent having the knots on the labrum and capsule to avoid potential abrasion issues. An anchor placed medially (percutaneously through the subscapularis) into the glenoid can greatly assist the reduction of the bone fragment by placing sutures medial to the fragment. Two additional suture anchors are then placed – one at the top of the fragment and bottom of the fragment with a capsulolabral repair so that the fragment is fixed medially, and then superiorly and inferiorly. Bridge suturing techniques and other hybrid suture-fixation constructs have been descried. In general, I would try to restore the anatomy by repairing the bone to the glenoid with a combination of small screws and suture anchors, or by complete arthroscopic technique as described above. The principle is that the glenoid failure was through the bone and the labrum is generally intact to the bone and shoulder be repaired. Based on this, there is usually not the need for coracoid transfer in an acute fracture.

Levine: How would you manage a 25-year-old right-hand dominant male with a 30% glenoid bone deficit and a small Hill-Sachs lesion?

Ahmad: We consider this degree of bone deficiency significant and requires bone augmentation for the most predictable successful outcome. Our preferred technique is to perform a diagnostic arthroscopy, perform a posterior inferior labral repair and or SLAP repair as indicated, prepare the anterior glenoid, followed by open Latarjet or Bristow coracoid transfer.

Cadet: If the dislocation event was acute and there was the presence of the bone fragment in its entirety without significant comminution, I would attempt to repair arthroscopically with double row suture anchor (ORIF of fragment by the technique as I previously described) or with screw fixation (open or arthroscopically). I probably would not address the Hill-Sachs lesion. If this is in the chronic setting, I would treat with an open, modified-Latarjet technique, as described by Young et al.

Edwards: At risk of sounding dogmatic, I would also address this patient with a Latarjet procedure primarily.

Mazzocca: We would do an open Latarjet procedure.

Provencher: For a young patient with a large bone deficit, I would manage this with a glenoid bone augmentation, such as the Latarjet or allograft bone. The Latarjet provides an elegant solution to this problem in that the conjoint tendon when placed through a split in the subscapularis provides a sling-type effect for additional stability besides the bony augmentation. I have recently started to use fresh distal tibia allograft for the treatment of glenoid bone deficiency. We have found that the lateral side of the distal tibia fits provides excellent conformity to the glenoid and humeral head, is easy to obtain since it is an unmatched graft. Although this technique has still not been fully proven, it might be an option to restore the cartilage and bone stock that is deficient in this case.

Levine: Do you ever perform a Bristow procedure? How do you decide between a Bristow and Latarjet? What technical pearls can you share to avoid complications for Latarjet?

Ahmad: I believe both the Bristow and Latarjet procedure have advantages and disadvantages. The Bristow procedure offers advantages of decreased exposure to the glenoid and therefore an easier approach through a subscapularis split, a single screw for fixation, potential to have greater increase in the glenoid articular arc, and perhaps have the strap muscles located at a more advantageous position slightly more anterior when compared to the Latarjet procedure. The disadvantages are that fixation is with a single screw, and the glenoid bone restoration does not extend superiorly and inferiorly when compared to the Latarjet with two points of fixation and has greater bone augmentation from the superior and inferior aspects. While I routinely perform both Bristow and Latarjet procedures, I have not formulated exact criteria for when it is advantageous to use one over the other.

Cadet: In general, I prefer performing a Latarjet procedure. The Latarjet affords greater osseous surface area to facilitate bone healing and may restore the arc of the glenoid greater than the Bristow. The Bristow is definitely an acceptable option. I would perform a Bristow procedure over a Latarjet in cases of lesser amounts of glenoid bone loss and for smaller individuals. The reason for the Bristow in the latter scenario is that the length of the coracoid, or the distance from the tip of the coracoid to the coracoclavicular ligaments, may be shorter in such individuals. By performing the Bristow, you avoid iatrogenic injury to the coracoclavicular ligaments.

I find the exposure of the medial glenoid neck is the most difficult part of the case, particularly when performing a longitudinal split of the lower subscapularis. Using a second link retractor to maintain the split of the subscapularis may be helpful. Also, the direction of the screw must be parallel to the articular surface of the glenoid surface. I will use a guide pin and start it at the mark where I want the center of the coracoid transfer to be located. I then use the guide pin to direct the proposed drill path from anterior-to-posterior on the glenoid and confirm using an axillary fluoroscopic view intraoperatively. I will then create the screw hole with a cannulated drill bit over the guide pin. For final fixation, I remove the guide pin and use partially threaded non-cannulated 4.5-mm screws.

Edwards: I have never performed a Bristow procedure, mainly because I was taught the Latarjet procedure by Gilles Walch after the Bristow had fallen out of favor in North America. The Latarjet procedure as done by Gilles seems more theoretically sound than the traditional Bristow; a larger glenoidplasty is performed and use of two screws helps avoid graft nonunion. When performing the Latarjet procedure, it is important to place the graft flush with the glenoid rim or slightly medial to avoid an overhanging coracoid process, which has been shown to contribute to the formation of glenohumeral arthritis (Figure 2). When tightening the screws for coracoid fixation use only thumb and fingertip pressure to avoid coracoid fracture. Lastly, when suturing the coracoacromial ligament stump to the inferior glenohumeral ligament, position the arm in external rotation to avoid introduction of postoperative stiffness in external rotation.

Postoperative Bernageau glenoid
Figure 2. Postoperative Bernageau glenoid profile radiograph shows the coracoid graft fixed flush with the glenoid rim.

Image: Edwards B

Mazzocca: I only perform a Latarjet coracoid transfer. The technical pearls I can offer are that we place the patient in 10% to 15% of forward flexion of the spine in a supine position, a true “beach chair” type positioning. I feel that the more supine they are, the easier it is to get to the position that I want to get. I also stabilize the scapula with a square gel-foam pad augmented with a folded blue towel. This really secures the scapula so it doesn’t “run away” or move while drilling. We use a commercially available system that has a handle that orients the two drill holes in the coracoid process and secures the coracoid so that you can position it where you want as you advance the screws.

Provencher: I have not performed a Bristow procedure, but rather perform a Latarjet. The difference is basically the amount of bone that is transplanted to the glenoid and is usually fixed with either one screw (Bristow) or two screws (Latarjet). The Latarjet generally provides about 20 mm to 25 mm of bone superior to inferior. There are two ways to orient the coracoid. The classic way is to have the lateral edge of the coracoid as the glenoid face, which allows excellent conformity to the glenoid-coracoid interface. The coracoacromial ligament may be incorporated into the repair and allows solid bone stock. The other way to orient the coracoid in a Latarjet is to rotate it 90° such that the inferior surface is the glenoid face which are both concave. We have found that this “fits” better, but the bone is thinner in which to provide screw fixation and is more technically demanding.

The Latarjet is a technically demanding procedure, and there are multiple pearls:

  • Obtain sufficient bone when performing the coracoid osteotomy with an osteotome or 90° thin sagittal saw. You know that there is enough bone if the coracoid elbow is part of the osteotomy.
  • Perform a subscapularis split in the middle of the subscapularis. Stay lateral to the coracoid to avoid the innervation to the subscapularis.
  • The capsule is found best medially and near the glenoid face, not laterally.
  • Capsular and labral management are the most difficult aspects of the procedure. The capsule is easier to dissect medially off the glenoid neck with the labrum attached. This can then be reattached to the native glenoid to make the Latarjet bone block an extra-articular graft.
  • Ensure that the graft is flush to the glenoid – if not, a high speed burr may be used to make the bone flush.
  • Repair the capsule that was dissected medially off the glenoid neck to two suture anchors on the inferior portion of the native glenoid.

Levine: Why do you think the coracoid transfer works? Which of the proposed theories do you feel are most important?

Ahmad: Coracoid transfer has several features that contribute to glenohumeral stability. First, the bone deficiency associated with instability is improved by increasing the articular arc on the glenoid. In addition, there is a dynamic effect from the strap muscles, which become tensioned as the arm moves into abduction and external rotation – the position of instability. In addition, when the coracoid is placed through a split in the subscapularis, the inferior component of the subscapularis does not shift superiorly and becomes tensioned in external rotation and abduction. These three components are contributing factors to stabilization with coracoid transfer procedures.

Cadet: I have often thought about this question. I do believe there is a sling/tenodesis effect of the conjoint tendon with the subscapularis tendon. I believe with the modified-Latarjet procedure, the imbrication of the lateral capsule with the lateral coracoacromial ligament does provide additional stability. Increasing glenohumeral surface area by restoring the bone defect is also accomplished with coracoid transfers, however, I believe allograft (e.g., distal tibia) may restore the articular arc more accurately.

Edwards: Although a recent laboratory study performed at the Mayo clinic suggests that the coracoid bony effect is the most important functional aspect of the Latarjet procedure, clinical evidence suggests that the dynamic sling effect that occurs as the conjoined tendon reinforces the inferior subscapularis as the arm is placed in abduction external rotation is the most important stabilizing mechanism (Figure 3). Hovelius found that postoperative stability is uncompromised even if the coracoid transfer is placed up to 8 mm medial to the glenoid rim suggesting that the muscle transfer is more important than the glenoidplasty effect. Additionally, the same study found that fibrous union of the coracoid transfer had no effect on stability. Lastly, when performed as described by Walch, the Latarjet does not create an obligate reduction in external rotation.

Conjoined tendon sling
Figure 3. Conjoined tendon sling reinforces the inferior subscapularis during abduction and external rotation.

Image: Edwards B

Mazzocca: From listening to various leaders, I feel that it is a combination of these. My personal preference, if I were to choose one, is for the articular arc to be lengthened.

Provencher: The Latarjet has been an excellent and reliable procedure for more than 50 years, however, it is a non-anatomic repair. Regardless, it works on the principles of both bony restoration of the glenoid, as well as soft tissue “hammock” of the conjoined tendon that is placed through a subscapularis split. The so-called “sling effect” has now been proven biomechanically to provide added support to the bony repair and is an important aspect of the overall repair construct. However, we know that restoration of the bony congruity of the glenoid with a well done capsulolabral repair is an excellent anatomic option.

Levine: Remplissage (infraspinatus capsulodesis) has become popular at meetings with little scientific data to support its use at this time. Do you perform this procedure and when would you consider it?

Ahmad: While I am intrigued with the Remplissage procedure and value its simplicity from a technical arthroscopic standpoint, I maintain reserved in its use. I have concerns that with external rotation the new infraspinatus attachment will experience significant shear forces at its attachment site on the humeral head. This may result in failure, pain or stiffness. A technical pearl of doing a partial articular surface tendon avulsion (PASTA) repair, which is an anatomic restoration of the supraspinatus when it is detached, has similar technical features to the Remplissage. In certain athletes and in particular overhead athletes, in situ repair of a PASTA lesion can cause symptoms of stiffness, pain and failure of the repair. This is attributed to internal impingement contact of the repair against the glenoid. While this is not completely analogous to the Remplissage procedure, the Remplissage procedure does create a non-anatomic position of the infraspinatus that can limit rotation and change the infraspinatus function and cause internal impingement.

Cadet: I do not routinely perform this procedure for anterior instability. I would consider remplissage in cases of large (>30%) and deep (>4 mm) Hill-Sachs lesions. I would not perform a Remplissage in a patient who requires significant external rotation for their sport or occupation for potential losses of rotation that can occur following infraspinatus capsulodesis.

Edwards: I do not perform the Remplissage procedure. An engaging Hill-Sachs lesion that requires direct treatment of the bony defect is very rare in my practice. I worry about potential loss of internal rotation with this procedure although recent clinic studies by Pascal Boileau and others have not demonstrated any significant loss of mobility following the Remplissage procedure.

Mazzocca: I have to admit that I have performed this procedure in patients that are somewhat older with less demand and who have had chronic dislocation or subluxation events who are not interested in a large open bony procedure. The patient will choose the arthroscopic procedure, and we will attempt to limit the amount of bony involvement while we perform it. We will use the abduction position at about 30° but do not use any overhead distraction. We will put a cannula in posteriorly and, after preparing the Hill-Sachs lesion, put our anchor in, then pass our sutures and hold the sutures outside of the cannula. We then continue with the remainder of the arthroscopic labral repair, shifting inferior to superior and recreating the bony bumper. Generally speaking, we will also be aggressive to fix anything posteriorly and posterior- inferiorly, as well. After fixing this, we will go back to the posterior cannula and complete the remplissage (infraspinatus and posterior capsulodesis).

Provencher: I rarely perform a Remplissage procedure. If the Hill-Sachs is significant enough to be addressed, there is almost always a corresponding glenoid bone injury or glenoid bone loss that should be addressed. If the glenoid is primarily addressed with a bony augmentation procedure, then the Hill-Sachs is effectively neutralized and not necessary to treat. However, in the rare case of humeral head deficiency without glenoid bone loss, or an extreme Hill Sachs (35% to 45%) and glenoid bone deficiency as commonly occurs in seizure disorders or electric shocks, I generally perform a humeral head allograft (fresh) to the defect. It should be noted that the defect is almost always the shape of an orange slice, thus an allograft has to be shaped to fit in the defect and I usually fix with variable compression headless screws. I do not do partial resurfacings as I have found that the round resurfacings do not fit well into the humeral head defect.

Levine: If you do not perform Remplissage and prefer to “fill” the humeral defect do you perform an osteochondral allograft? When would you consider a humeral partial resurfacing prosthesis?

Ahmad: The indications for managing bone deficiency on the humeral head is controversial. In patients who have extreme bone deficiency (30%-40%), such as those with chronic dislocations or with seizure disorders, I consider osteochondral humeral head allografting. For an older patient, a patient with smoking history or other features that would negatively influence allograft healing, I consider a partial resurfacing prosthesis to fill the bony deficiency. Both options have been successful.

Cadet: I prefer osteochondral allograft. I think they can provide a “custom fit” of the defect and replace articular cartilage with articular cartilage. Although partial humeral resurfacing prostheses are readily available and eliminate the risk of disease transmission with osteochondral allograft (albeit very low risk), I believe one can probably match the convexity of the humeral defect closer with osteochondral allograft although more studies would need to be performed to confirm such comments.

Edwards: I have been successful to this point by addressing large humeral defects by using the glenoidplasty effect of the Latarjet procedure. By increasing the anteroposterior diameter of the glenoid, in most cases it becomes impossible for the humerus to translate anteriorly enough to engage and dislocate the glenohumeral joint.

Mazzocca: We have done both of these. We would do a humeral osteochondral allograft in a younger person. We would consider a humeral partial resurfacing prosthesis in an older person, in a person who may not be as compliant or in a person in which we want to make sure that we have good rotational control.

Levine: Pascal Boileau, MD, and Laurent Lafosse, MD, have popularized arthroscopic Bristow and Latarjet procedures in France. Are you performing this type of procedure? What role these procedures will play in the future?

Ahmad: Several features of arthroscopic Bristow and Latarjet procedures are appealing. They include decreased surgical morbidity to the subscapularis and accurate positioning of the bone on the glenoid articular surface. At this time, however, I feel the procedure is in a process of evolution and continues to be modified and improved. Recent introduction of new instrumentation has improved the technical aspects, but at the present time I have not incorporated it into my practice.

Cadet: Boileau and Lafosse are master arthroscopists and innovators of such procedures. In their hands, arthroscopic Latarjet procedures are probably no harder to do than open techniques. I perform these procedures open. With an open procedure in my hands, I believe I can get it right the first time, as revision is difficult. I would warn against the junior arthroscopist performing these procedures arthroscopically, as they are technically demanding enough with open techniques.

I believe that arthroscopic coracoid transfers will play an increasingly larger role in the future as we get more familiar with the subdeltoid arthroscopic anatomy and training programs begin incorporating such procedures in their curriculum. It provides the benefits of possibly greater visualization. However, downfalls include increased surgical time and fluid extravasation into the chest wall for those surgeons who do not perform these procedures regularly.

Edwards: I have not yet performed the arthroscopic Latarjet procedure mainly because of increased operative time involved (three to four times longer than an open Latarjet in the best cases). I know Pascal has developed some new instrumentation to facilitate performance of the arthroscopic Latarjet and plan on trying it when it becomes available. I think it is important not to discount the arthroscopic Latarjet as it may become standard of care in the future in much the same way arthroscopic meniscectomy has totally supplanted open menisectomy in the knee.

Mazzocca: We do not use the arthroscopic procedure at this time. I commend these surgeons for “pushing the envelope.” I think that it is the hallmark for improving patient care and look forward to learning from them in the future.

Provencher: I have not performed the arthroscopic Latarjet in a patient. This remains a very challenging case requiring significant expertise. However, I have performed arthroscopic allograft procedures and fixed the bone percutaneously. I think that if an allograft becomes a viable option for bony defects and that we can preserve the coracoid and conjoint tendon, an arthroscopic approach and all-arthroscopic fixation would be a potentially good solution.

References:
  • de Beer JF, Roberts C. Glenoid bone defects – open latarjet with congruent arc modification. Orthop Clin North Am. 2010;41(3):407-415.
  • Kim KC, Rhee KJ, Shin HD. Arthroscopic three-point double-row repair for acute bony Bankart lesions. Knee Surg Sports Traumatol Arthrosc. 2009;17(1):102-106.
  • Millett PJ, Braun S. The “bony Bankart bridge” procedure: A new arthroscopic technique for reduction and internal fixation of a bony Bankart lesion. Arthroscopy. 2009;25(1):102-105.
  • Young AA, Maia R, Berhouet J, Walch G. Open Latarjet procedure for management of bone loss in anterior instability of the glenohumeral joint. J Shoulder Elbow Surg. 2011;20(2 Suppl):S61-69.

  • Christopher S. Ahmad, MD, can be reached at the Center for Shoulder, Elbow and Sports Medicine, Columbia University, 622 W. 168th St., New York, NY 10032; 212-305-5561; email: csa4@columbia.edu.
  • Edwin R. Cadet, MD, can be reached at Columbia University Medical Center, 622 W. 168th St., PH-1117 Center, New York, NY 10032; 212-305-4626; email: ec2195@columbia.edu.
  • T. Bradley Edwards, MD, can be reached at Fondren Orthopedic Group LLP, 7401 South Main St. Houston TX 77030; 713-799-2300; email: bemd@fondren.com.
  • William N. Levine, MD, can be reached at Columbia University Medical Center, 622 W. 168th St., PH-1117r, New York, NY 10032; 212-305-0762; email: wnl1@columbia.edu.
  • Augustus D. Mazzocca, MS, MD, can be reached at New England Musculoskeletal Institute, Medical Arts and Research Building, Room 4017, University of Connecticut, 263 Farmington Ave., Farmington, CT 06034-4037; 860-679-6633; email: admazzocca@yahoo.com.
  • Matthew T. Provencher, MD, CDR, MC, USN, can be reached at the U.S. Naval Medical Center, San Diego, Department of Orthopaedic Surgery, 34800 Bob Wilson Drive, San Diego, CA 92134; 619-532-8427; email: matthew.provencher@med.navy.mil.
  • Disclosures: Ahmad is a paid consultant for Arthrex and Acumed, and receives research support from Stryker, Zimmer and Arthrex. Cadet previously received research support in the form of research materials from Smith & Nephew. Edwards, Levine and Provencher have no relevant financial disclosures. Mazzocca is consultant for and receives research funding from Arthrex Inc.