A reverse Bankart lesion is a tear or detachment of the posterior labrum of the shoulder, the cartilage rim that helps keep the ball of the upper arm bone seated in the socket. It occurs during a posterior shoulder dislocation, when the humeral head is forced backward out of the joint, and is essentially the mirror image of the more commonly discussed (anterior) Bankart lesion. Because posterior dislocations account for a small fraction of all shoulder dislocations, the reverse Bankart lesion is far less familiar to most people, and it is frequently missed on initial evaluation.
What Makes It “Reverse”
A standard Bankart lesion involves the front (anterior) part of the labrum tearing away from the glenoid, the shallow socket of the shoulder blade. It happens during the much more common anterior dislocation, where the arm is forced outward and backward. A reverse Bankart lesion is the same type of damage, just at the back (posterior) of the socket. The labrum peels off the posterior glenoid rim, and the capsule and ligaments attached to it may stretch or tear along with it.
The distinction matters because the posterior labrum plays a somewhat different stabilizing role than the anterior labrum. In a cadaver study, creating a posteroinferior Bankart lesion increased posterior translation of the humeral head by about 86% and inferior translation by about 31%, demonstrating how much stability the posterior labrum contributes to keeping the joint in place.1PubMed. The biomechanical effect of specific labral and capsular lesions on posterior shoulder instability That degree of looseness explains why people with a reverse Bankart lesion often feel the shoulder slipping or catching during everyday overhead movements, not just during forceful activity.
How the Injury Happens
Posterior shoulder dislocations are uncommon compared with anterior dislocations. They tend to occur from a direct blow to the front of the shoulder, a fall onto an outstretched hand with the arm internally rotated, or during seizures and electric shocks, which cause violent involuntary muscle contraction. In these scenarios the humeral head is driven backward, shearing the posterior labrum off the glenoid rim as it goes.
The force and duration of the dislocation determine how much damage occurs. In an MRI study of patients with acute traumatic posterior dislocations, posterior labrocapsular complex tears were found in about 58% of cases, with roughly half of those being reverse Bankart lesions (complete labral detachments) and the other half being sleeve-type avulsions where the labrum peeled away but stayed partially connected.2Radiology. Acute traumatic posterior shoulder dislocation: MR findings Not every posterior dislocation tears the labrum cleanly; some produce incomplete detachments, concealed avulsions, or erosion of the cartilage surface rather than a full-thickness tear.3PubMed. Arthroscopic capsulolabroplasty for posteroinferior multidirectional instability of the shoulder
The Reverse Hill-Sachs Lesion and Other Companion Injuries
A reverse Bankart lesion rarely travels alone. When the humeral head slams backward over the glenoid rim, the rim can gouge an impression fracture into the front of the humeral head. This dent is called a reverse Hill-Sachs lesion (sometimes called a McLaughlin lesion), and it mirrors the more familiar Hill-Sachs dent seen on the back of the humeral head after anterior dislocations.
The size of a reverse Hill-Sachs defect depends heavily on how long the shoulder stayed dislocated. Research classifying these defects into three categories found that a simple dislocation that was reduced promptly produced a defect averaging about 33 degrees of the humeral head arc. When the dislocation was locked (not reduced quickly), the defect grew to roughly 49 degrees. In chronic locked dislocations that went unrecognized for weeks or longer, the defect ballooned to about 64 degrees on average.4PubMed Central. Defect Characteristics of Reverse Hill-Sachs Lesions Larger defects are more likely to “engage” the glenoid rim during shoulder motion, meaning the dent catches on the socket edge and causes the shoulder to subluxate or redislocate. This engagement risk is a major factor in deciding whether the defect needs its own surgical procedure beyond just fixing the labrum.
Other injuries that can accompany a reverse Bankart lesion include fractures of the posterior glenoid rim (a bony reverse Bankart), fractures of the lesser tuberosity, posterior labral cysts, and stretching or redundancy of the posterior capsule.5PubMed Central. Clinical, Diagnostic, and Therapeutic Characteristics of Posterior Glenohumeral Instability The overall pattern of damage shapes the treatment plan far more than the labral tear alone.
Why It Is So Often Missed
Posterior shoulder dislocations are sometimes called the most commonly missed major dislocation in emergency medicine. The shoulder may look relatively normal on a standard front-to-back X-ray, and the arm can still move through a limited range of motion. Patients are frequently sent home with a diagnosis of “shoulder sprain” only to be identified weeks or months later when the shoulder keeps giving way.
Imaging of the posterior labrum is also more challenging than imaging of the anterior labrum. One study comparing MR arthrography findings to arthroscopy found that the sensitivity for detecting posterior labral tears was only about 40 to 50%, depending on the radiologist’s experience, even though specificity was reasonably high.6Shoulder & Elbow. Magnetic Resonance Arthrogram and Arthroscopy of the Shoulder: A Comparative Retrospective Study with Emphasis on Posterior Labral Lesions and Radiologist Locality In other words, when the MRI said the posterior labrum was torn, it usually was, but a clean-looking MRI did not reliably rule out a tear. A larger analysis from the MOON Shoulder Instability Group found that both standard MRI and MR arthrography had high sensitivity for labral tears in general (about 95 to 98%) but low specificity, suggesting that while the scans rarely miss a labral tear entirely, they can struggle to characterize the exact nature and location of posterior pathology.7Orthopaedic Journal of Sports Medicine. Paper 41: Does MR Arthrography Improve Evaluation of Patients with Posterior Shoulder Instability?
The clinical takeaway is that a negative MRI does not rule out a reverse Bankart lesion if the history and physical exam are suspicious. Exam findings that raise the index of suspicion include a positive posterior load-and-shift test (where the examiner pushes the humeral head backward and feels it translate excessively) and a positive posterior apprehension test (where the patient resists or becomes anxious when the arm is pushed into forward flexion and internal rotation). When the clinical picture is strong but imaging is equivocal, diagnostic arthroscopy sometimes becomes necessary to confirm the diagnosis.
How Posterior Bone Loss Changes the Equation
When a piece of the posterior glenoid rim breaks off along with the labrum, the injury is called a bony reverse Bankart lesion. This matters because bone loss reduces the effective depth of the socket and makes the shoulder easier to redislocate. Biomechanical testing has shown that the force needed to dislocate a shoulder posteriorly drops significantly even with a small amount of posterior glenoid bone loss, and the drop accelerates as the defect grows larger.8PubMed. Biomechanical Evaluation of Posterior Shoulder Instability With a Clinically Relevant Posterior Glenoid Bone Loss Model Labral repair still increased the force required to dislocate the shoulder regardless of bone loss severity, but it could not fully compensate for a large bony deficit. That finding helps explain why soft-tissue repair alone sometimes fails in patients with significant glenoid bone loss, and why surgeons have developed bone-augmentation procedures for these cases.
Conservative Treatment and When It Makes Sense
Not every reverse Bankart lesion needs surgery. The decision depends on the severity of instability, the extent of bone loss, the patient’s activity level, and their goals. Patients with a first-time posterior dislocation, minimal bone damage, and no engaging reverse Hill-Sachs lesion are often managed conservatively with a period of immobilization followed by physical therapy focused on strengthening the posterior rotator cuff and scapular stabilizers.9PubMed Central. Clinical, Diagnostic, and Therapeutic Characteristics of Posterior Glenohumeral Instability
Rehabilitation for posterior instability differs from the more commonly discussed anterior instability programs. The emphasis shifts to the infraspinatus and teres minor muscles, which externally rotate the arm and resist posterior translation. Exercises that load the shoulder in a position of forward flexion and internal rotation (the position that stresses the posterior labrum) are introduced gradually and carefully. Return to full activity after conservative treatment typically takes several months, and the decision to proceed to surgery is usually made when instability symptoms persist despite a dedicated rehabilitation program.
Surgical Repair of the Posterior Labrum
When conservative treatment fails, arthroscopic posterior labral repair is the standard surgical approach. Indications include a symptomatic posterior labral tear confirmed on imaging in a patient who has not improved with activity modification, anti-inflammatory medication, and physical therapy, and who demonstrates clinical signs of posterior instability on exam.10PubMed Central. Arthroscopic Reverse Bankart Surgical Repair
The procedure involves reattaching the torn posterior labrum to the glenoid rim using suture anchors, small devices that are drilled into bone and hold stitches that pull the labrum back into position. When the posterior capsule has been stretched out (which is common after repeated subluxation events), the surgeon also tightens it by folding and stitching the redundant tissue, a step called capsular plication. Addressing both the labrum and the capsule together produces better results than fixing the labrum alone.11PubMed Central. Evaluation and Management of Posterior Shoulder Instability
Biomechanical cadaver testing has supported the effectiveness of this approach. Compared with a bone block procedure (where a piece of bone is grafted onto the posterior glenoid to build up the socket), arthroscopic labral repair restored posterior and inferior shoulder translation to essentially normal levels without overcorrecting. The bone block procedure, by contrast, overcorrected posterior translation, making the shoulder tighter than its native state in the posterior direction while still failing to fully restore inferior stability.12PubMed. Biomechanical effectiveness of an arthroscopic posterior bankart repair versus an open bone block procedure for posterior shoulder instability This overcorrection is not trivial; it can limit motion and alter joint mechanics in ways that may cause problems over time.
When Bone Grafting or Remplissage Is Needed
For patients with a bony reverse Bankart lesion or an engaging reverse Hill-Sachs defect, soft-tissue repair alone may not be enough. In these cases, surgeons may reduce and fix the glenoid bone fragment back to the rim with suture anchors, and then address the humeral head defect with a technique called remplissage. Remplissage (French for “filling in”) involves placing suture anchors into the reverse Hill-Sachs defect and passing sutures through the adjacent capsule and infraspinatus tendon, essentially filling the dent with soft tissue so it can no longer catch on the glenoid rim.13PubMed Central. Arthroscopic Repair of Posterior Bony Bankart Lesion and Subscapularis Remplissage This combination approach addresses both the socket-side and ball-side components of the instability in a single arthroscopic procedure.
For very large glenoid defects where there is not enough bone left to reconstruct, a posterior bone block procedure using autograft (bone harvested from the patient’s own body, often from the iliac crest or scapular spine) or allograft may be necessary. These are more invasive operations and are generally reserved for cases where the bone loss is too extensive for anchor-based repair. As the biomechanical data mentioned earlier suggests, bone block procedures carry a risk of overcorrecting posterior translation, and clinical data backs this up with higher complication rates.
Long-Term Outcomes and Complication Rates
The long-term track record for arthroscopic posterior Bankart repair is encouraging. A study comparing arthroscopic posterior Bankart repair to posterior bone block procedures at an average of eight years of follow-up found that recurrence rates were low and statistically similar for both approaches, roughly 4% for the arthroscopic repair group and about 6% for the bone block group. The real difference showed up in complications and reoperations. The arthroscopic repair group had a revision rate of about 4%, compared with about 33% for the bone block group. Complication rates followed the same pattern: roughly 4% versus 50%.14PubMed Central. Recurrence Rate, Complications and Revisions in Long-term Follow-up of Arthroscopic Posterior Bankart Repair Compared to Posterior Bone Block Both groups achieved good clinical and functional outcomes with high satisfaction, but the dramatically lower complication burden with arthroscopic repair explains why it is the preferred first-line surgical option when bone loss is not severe.
The high complication rate for bone blocks includes issues like hardware irritation, graft resorption, nerve injury, and loss of fixation. These are largely mechanical problems related to placing a bone graft in a tight space near critical structures. When a bone block is truly indicated (because of extensive posterior glenoid bone loss), these risks are accepted as the tradeoff for restoring enough socket depth to prevent redislocation. But the data makes a strong case for not jumping to a bone block when a labral repair can do the job.
Return to Sport After Posterior Labral Repair
Athletes are often the most motivated patients seeking repair, and also the ones most anxious about whether their shoulder will perform the same afterward. While the bulk of published return-to-sport data focuses on anterior Bankart repairs rather than posterior ones specifically, the available evidence from overhead athletes is informative. A study of professional baseball players who underwent Bankart repair found that position players returned to sport at a rate of about 95%, while pitchers returned at a lower rate of roughly 72%. Position players took about 245 days to return, and pitchers took about 334 days. Interestingly, when position players had their throwing shoulder repaired (rather than the non-throwing shoulder), their return timeline extended by about 100 additional days.15Journal of Shoulder and Elbow Surgery. Return to sport and performance outcomes after isolated Bankart repair in professional baseball players
A reassuring finding from that study was that performance statistics did not decline after surgery. Pitchers maintained their earned run average and walks-plus-hits-per-inning numbers, and position players maintained their batting and on-base percentages. The shoulder held up under the demands of professional play without measurable performance degradation. While these results come from anterior Bankart repairs in a young, elite population and cannot be directly mapped onto all reverse Bankart repair patients, they suggest that labral repair in general does not doom an athlete to a lesser version of their sport.
How Posterior Instability Differs From Anterior Instability in Practice
People familiar with anterior shoulder instability sometimes assume the posterior version is just the same problem at the back of the joint. In broad strokes that is true, but several practical differences matter. Posterior instability more often presents as recurrent subluxation (partial slipping) rather than full dislocation. Many patients with a reverse Bankart lesion never experience a dramatic dislocation event; instead, they notice the shoulder feels loose, catches, or aches with activities like push-ups, bench pressing, or any motion that loads the arm in a forward-flexed, internally rotated position.
The subtlety of the symptoms means that posterior instability is often diagnosed later in its course than anterior instability. Patients may be treated for impingement syndrome or rotator cuff problems for months before someone considers a posterior labral tear. The physical exam tests for posterior instability, like the jerk test and the Kim test, are less widely performed and less familiar to many clinicians than the anterior apprehension test. This diagnostic lag is one reason the reverse Bankart lesion has a reputation as an underappreciated injury.
Surgically, the posterior approach also carries specific anatomical considerations. The axillary nerve and posterior circumflex humeral artery run close to the inferior aspect of the posterior glenoid, and the suprascapular nerve courses nearby, making anchor placement in the posteroinferior glenoid more delicate than corresponding anterior repairs. Surgeons working in this area rely on careful portal placement and awareness of these structures to avoid nerve injury.
Seizure-Related and Electroconvulsive Therapy Cases
One population that sees a disproportionate number of reverse Bankart lesions is people who experience seizures. During a grand mal seizure, the powerful involuntary contraction of the internal rotator muscles of the shoulder (the subscapularis, pectoralis major, and latissimus dorsi) can drive the humeral head posteriorly with tremendous force. Because the person is unconscious and the muscles are contracting simultaneously from both sides, bilateral posterior dislocations can occur, a combination that is almost pathognomonic for seizure activity. Historically, electroconvulsive therapy was another common cause before modern protocols introduced muscle relaxants during the procedure.
These cases are especially prone to delayed diagnosis. The patient may be postictal and confused, unable to report shoulder pain clearly, and the attending physicians may be focused on the neurological event rather than the musculoskeletal one. A posterior dislocation that remains unreduced for days or weeks produces a much larger reverse Hill-Sachs defect and more extensive labral damage, as the research on locked dislocations and defect size demonstrates.16PubMed Central. Defect Characteristics of Reverse Hill-Sachs Lesions For patients with epilepsy or other seizure disorders, any shoulder complaint after a seizure should prompt dedicated imaging to rule out a posterior dislocation and its associated injuries, including a reverse Bankart lesion.