Bennett Lesion Resection and Posterior Labral Repair Using a 2-Portal Technique

Abstract

A Bennett lesion is a bony ossification that forms along the posteroinferior aspect of the glenoid rim, most frequently found in baseball players. Bennett lesions are most often asymptomatic in throwing athletes but can become symptomatic and, in some cases, lead to posterior labral tearing. Few techniques have been described regarding their surgical management. We present an arthroscopic 2-portal technique for Bennett lesion resection, posterior labral repair, and posterior capsulotomy.

A Bennett lesion, or thrower’s exostosis, is a bony ossification that forms along the posteroinferior aspect of the glenoid rim, most frequently found in baseball players. It is thought to be due to repetitive traction on the capsule and glenohumeral ligaments from overhead throwing.1, 2, 3, 4, 5, 6 Bennett lesions are most often asymptomatic in throwing athletes, with nearly 1 of 4 Major League pitchers having asymptomatic lesions, suggesting they can be a physiological adaptation to throwing.⁷

The Bennett lesion can cause symptoms by several mechanisms. They can irritate the capsule and axillary nerve, resulting in focal tenderness along the posteroinferior glenoid, radiating shoulder pain, and pain during the late cocking and follow-through phases of throwing.8, 9, 10 The bone lesion may also fracture and lead to a painful nonunion. In addition, the lesion can compress the posterior rotator cuff and labrum, leading to rotator cuff inflammation and tearing, as well as posterior labral pathology ^5,11 In a small study of 22 collegiate and professional athletes, Meister et al.² reported that 68% of those with Bennett lesions had concomitant posterior labral tears.

Initially, symptoms are managed nonoperatively with posterior capsular stretching and rotator cuff strengthening.^12,13 Failure of nonoperative management most often leads to surgical intervention in the form of arthroscopic Bennett lesion resection while also addressing any other intra-articular pathology. Surgical management of labral pathology varies and depends on the type of labral lesion. Simple fraying can be managed with debridement in conjunction with Bennett lesion resection, whereas extensive tearing is most often managed with labral repair.¹² Posterior capsulotomy can be performed to obtain lesion access and to address capsular contracture. Some authors prefer to repair the capsulotomy once complete, particularly in the setting of posterior instability, whereas others leave the capsulotomy open to help improve glenohumeral internal rotation deficit (GIRD).^3,11,12,14

There is a paucity of literature guiding the treatment of Bennett lesions. Few techniques have been described regarding their surgical management. We present an arthroscopic 2-portal technique for Bennett lesion resection, posterior labral repair, and posterior capsulotomy (Figs 1 and 2).

Fig 1.

Axillary lateral (A) and anteroposterior (B) radiographs of the right shoulder showing the presence of a Bennett lesion (blue arrows). (R, right.)

Fig 2.

Sagittal (A) and axial (B) T2-weighted magnetic resonance images of the right shoulder revealing a posterior labral tear and Bennett lesion (blue arrows).

Surgical Technique

Positioning and Portal Placement

An examination under anesthesia is performed with the patient in the supine position to assess shoulder laxity and range of motion with the scapula stabilized. These motions are compared with the contralateral side. The patient is subsequently placed in the lateral decubitus position with a beanbag positioner and axillary roll. The arm is then suspended at 20° of forward flexion and 45° of abduction with 12 lb of traction applied (Video 1).

Anatomic landmarks and portal sites are identified and marked on the skin (Fig 3). We create a posterolateral portal that can be used both for visualization and as a working portal. We typically place this portal midway between the standard posterior portal and the previously described 7-o’clock portal,¹⁵ 2 cm anterolateral to the posterolateral corner of the acromion. All work can be achieved via the posterior portal while viewing from the anterior portal.

Fig 3.

Right shoulder with the patient positioned in the lateral decubitus position, with the left side of the photograph corresponding to anterior. The skin markings display the locations for portal placement including the posterolateral portal (blue arrow), which can be used both for visualization and as a working portal. We typically place this portal midway between the standard posterior portal and the previously described 7-o’clock portal, 2 cm anterolateral to the posterolateral corner of the acromion.

The shoulder joint is entered posteriorly with a spinal needle, and 60 mL of normal saline solution is introduced into the shoulder joint for joint distraction. The posterior portal site skin is then incised, and a 5.0-mm cannula is inserted into the joint. A standard 30° arthroscopic camera is used. A spinal needle is then used to ensure the appropriate position of the anterior portal, which is made just lateral to the coracoid process and enters the rotator interval.

A standard diagnostic shoulder evaluation is performed from both the posterior and anterior portals. The posterior rotator cuff is assessed for injury due to internal impingement or the Bennett lesion abrading the cuff during the late cocking phase of throwing.

Labral Assessment and Bennett Lesion Exposure

To appropriately assess the lesion, we view from the anterior portal (Fig 4). A probe is introduced to assess the stability and degree of labral tearing. If the labrum is torn from the glenoid, the lesion can be accessed through the labral tear (Fig 5). An arthroscopic shaver is then used to debride any fraying of the posterior labrum. Once the lesion is fully identified, a 4.0-mm round burr (Arthrex, Naples, FL) is used to resect the Bennett lesion (Fig 6). In situations in which the labrum is frayed but not detached from the glenoid, the Bennett lesion can be accessed through a posteroinferior capsulotomy as described later.

Fig 4.

Viewing from the anterior portal, an arthroscopic shaver is introduced through the posterior portal. This identifies the posterior labral tear (blue arrow) adjacent to the hypertrophic capsulolabral tissue overlying the Bennett lesion.

Fig 5.

Viewing from the anterior portal, the Bennett lesion (blue arrow) exposure is obtained through the posterior labral tear from the posterior portal.

Fig 6.

Viewing from the anterior portal, a 4-mm round burr with a sheath is used to resect the Bennett lesion (blue arrow) through the posterior portal while protecting the soft tissues.

Capsulotomy

Through the same posterior portal, a 90° hooked arthroscopic electrocautery device (Smith & Nephew, Andover, MA) is used to perform a posteroinferior capsulotomy from the 3- to 6-o’clock position in a left shoulder and from the 9- to 6-o’clock position in a right shoulder (Fig 7). Care is taken to perform the capsulotomy just off the labrum so as not to damage the posterior rotator cuff tendon.

Fig 7.

Viewing from the anterior portal in the right shoulder, a complete posterior capsulotomy (blue arrows) is made using a hooked arthroscopic cautery wand through a posterior portal.

Labral Repair

For cases in which a posterior labral repair is required, a winged Gemini cannula (Arthrex) is placed posteriorly. In the experience of the senior author (R.V.O), the winged design prevents the cannula from backing out of the joint during the procedure, which occurs frequently with traditional screw-in cannulas. A drill guide for a 2.9 × 12.5-mm PEEK (polyether ether ketone) PushLock anchor (Arthrex) is then placed in the appropriate position on the face of the glenoid. We find it most efficient to place all drill holes prior to anchor placement to limit the number of instrument passes. The drill holes are marked with a small-tipped radiofrequency device for later identification. A 90° suture passer (Arthrex) is then brought in through the posterior cannula and passed through the capsule and under the labrum (Fig 8). A shuttling wire is advanced into the joint and retrieved through the same posterior portal. A 1.3-mm SutureTape (Arthrex) is then shuttled through the tissue with the wire. The suture is loaded into the anchor and tensioned appropriately. The anchor is then advanced into the predrilled hole. The suture is cut as flush as possible to the cartilage to prevent suture irritation. Sequential placement of anchors is then performed in the same manner.

Fig 8.

Viewing from the anterior portal, a 90° hooked suture passer is brought in through the winged Gemini posterior cannula and is passed through the capsule and under the labrum, with a shuttling wire introduced into the joint for retrieval through the same posterior portal.

Discussion

Arthroscopic management is the treatment of choice for Bennett lesions that are unresponsive to nonoperative measures. Although more recent studies suggest that resection of these lesions is important to eliminate the patient’s symptoms,^3,8 the initial descriptive study by Bennett¹ showed lesion resection to be unnecessary. We suggest individualized assessment of lesion size and position in guiding decision making when considering resection of the lesion. In our practice, the Bennett lesion is typically resected.

The increased stress and force on the posterior capsule with overhead throwing can lead to posterior capsular thickening, decreased internal rotation (GIRD), and exacerbation of internal impingement with rotator cuff and labral pathology. As depicted in the senior author’s technique for Bennett lesion resection, labral pathology and posteroinferior capsular tightness should also be addressed.

Meister et al.² examined 22 baseball players with posterior glenoid osteophytes for which failed nonoperative management failed. Asymmetrical loss of internal rotation was noted in all 22 patients. Fifteen were noted to have posterior labral fraying, with none having true detachment. After arthroscopic osteophyte resection and posterior capsular release, 16 of the 22 throwers were able to return to pain-free throwing at an average of 5 months postoperatively. Ten were able to maintain a high level of performance for a mean of 3.6 years.

Yoneda et al.³ studied 16 throwers with Bennett lesions. Of these 16 throwers, 4 had posterior labral tears that required repair. The authors reported excising the Bennett lesion through the site of labral detachment, similar to the depiction in our technique. In 14 of the athletes, the posterior capsule was repaired, with only 2 patients undergoing no posterior capsular repair. The article did not report on GIRD or posterior capsular tightness in the studied patients. Of the 16 throwers, 11 returned to the previous level of play after surgery.

Yoneda et al.¹⁶ reported a series of 16 patients with posterior capsular tightness in whom nonoperative management failed, requiring arthroscopic posterior capsular release. The presence of posterior stiffness and GIRD was confirmed with an examination under anesthesia. At 2-year follow-up, all patients reported complete resolution of their shoulder pain.

There are several advantages to the technique described in this article. Placement of the posterior portal between the standard posterior portal and the previously described 7-o’clock portal allows this portal to be used as both a working portal and a visualization portal. The trajectory allows for proper placement of glenoid anchors and is less anterior and lateral than the 7-o’clock portal, allowing for excellent visualization. Another advantage involves the use of a round burr with a sheath when resecting the Bennett lesion through the labral tear. This limits the potential to inadvertently damage the surrounding soft tissues. Additionally, using electrocautery to drill and mark the anchor holes limits the number of instrument passes and improves efficiency.

One disadvantage is the potential contribution to posterior shoulder instability without capsular repair. It is crucial to confirm the absence of posterior shoulder instability on examination under anesthesia prior to capsular release. Table 1 presents pearls and pitfalls of our technique, and Table 2 lists advantages and disadvantages.

Table 1.

Pearls and Pitfalls

Pearls

Lateral positioning allows for easy joint distraction for nearly circumferential labral access.

Placing a posterior portal between the standard posterior portal and the 7-o’clock portal allows for an appropriate path for both glenoid instrumentation and visualization.

Using a winged cannula prevents cannula pullout.

Posterior capsulotomy eliminates posterior capsular tightness.

Using a burr with a sheath prevents iatrogenic soft-tissue damage.

Knotless suture anchors prevent chondral damage from suture knot irritation.

Pitfalls

An examination under anesthesia must be performed to establish the presence of posterior instability or internal rotational deficit.

Care must be used while working through the posterior labral tear to avoid potential damage to the surrounding soft tissue.

The sutures must be cut flush to the anchor to avoid chondral damage from free suture strands.

Table 2.

Advantages and Disadvantages

Advantages

Placement of the posterior portal between the standard posterior portal and the previously described 7-o’clock portal allows this portal to be used as both a working portal and a visualization portal.

Using a round burr with a sheath when resecting the Bennett lesion through the labral tear limits the potential to inadvertently damage the surrounding soft tissues.

Using electrocautery to drill all anchor holes and mark them limits the number of instrument passes and improves efficiency.

Disadvantages

Capsulotomy could potentially contribute to posterior shoulder instability without capsular repair. It is crucial to confirm the absence of posterior shoulder instability on examination under anesthesia prior to capsular release.

The initial management of Bennett lesions in throwing athletes with or without associated shoulder pathologies is typically nonoperative and includes posterior capsular stretches, as well as rotator cuff and scapular strengthening programs. In athletes who are unable to return to sport after nonoperative treatment, arthroscopic management can have high success rates.¹² Decisions on management of associated shoulder pathologies with or without capsular repair should be made on a case-by-case basis to ensure the optimal outcome for each athlete.

Disclosures

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: All other authors (G.W., C.A.M.) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Supplementary Data

Video 1

Surgical technique for Bennett lesion resection and posterior labral repair using 2-portal technique.