Naoko Mizuno

Long-term results of the Latarjet procedure for anterior instability of the shoulder

BACKGROUND The Latarjet procedure is effective in managing anterior glenohumeral instability in the short term, but there is concern for postoperative arthritis. The purpose of this study was to evaluate the long-term functional outcome after the Latarjet procedure and to assess the prevalence of and risk factors for glenohumeral arthritis after this procedure. MATERIALS AND METHODS A retrospective review was conducted of 68 Latarjet procedures at a mean of 20 years postoperatively. The mean age at surgery was 29.4 years. Functional outcome was determined by the Rowe score, subjective shoulder value, and recurrence of instability. Preoperative arthritis and postoperative radiographs were reviewed to evaluate the development or progression of arthritis. RESULTS The mean Rowe score increased from 37.9 preoperatively to 89.6 at final follow-up (P < .001). The mean subjective shoulder value was 90.9% at final follow-up. The postoperative rate of recurrence was 5.9%. Of the 60 shoulders without arthritis preoperatively, 12 (20%) had developed arthritis at final follow-up. Among the 8 shoulders with preoperative arthritis (all stage 1), 4 (50%) demonstrated progression of arthritis at final follow-up. Overall, postoperative arthritis was stage 1 in 14.7%, stage 2 in 5.9%, and stage 3 in 8.8% of cases; no stage 4 arthritis was observed. Risk factors for postoperative arthritis were older age, high-demand sports activity, and lateral overhang of coracoid bone graft. CONCLUSION The Latarjet procedure provides excellent long-term outcomes in the treatment of recurrent anterior glenohumeral instability. Twenty years after the Latarjet procedure, arthritis may develop or progress in 23.5% of cases, but the majority of arthritis is mild.

Reverse Total Shoulder Arthroplasty for Primary Glenohumeral Osteoarthritis in Patients with a Biconcave Glenoid

BACKGROUND The biconcave glenoid in patients with primary glenohumeral osteoarthritis represents a surgical challenge because of the associated static posterior instability of the humeral head and secondary posterior glenoid erosion. The purpose of the present study was to evaluate the clinical and radiographic results of reverse total shoulder arthroplasty for the treatment of primary osteoarthritis in patients with a biconcave glenoid without rotator cuff insufficiency. METHODS We performed a retrospective review of twenty-seven reverse shoulder arthroplasties that were performed from 1998 to 2009 for the treatment of primary glenohumeral osteoarthritis and biconcave glenoid. Eighty-one percent of the patients were female, and the mean age of the patients at the time of surgery was 74.1 years (range, sixty-six to eighty-two years). All patients had a preoperative computed tomography arthrogram to allow for the measurement of glenoid retroversion and humeral head subluxation. The mean preoperative retroversion was 32°, and the mean subluxation of the humeral head with respect to the scapular axis was 87%. Seventeen patients had a reverse shoulder arthroplasty without bone graft, whereas ten had an associated bone graft to compensate for posterior glenoid erosion. Clinical outcomes were evaluated with the Constant score and shoulder range of motion. RESULTS The mean duration of follow-up was fifty-four months (range, twenty-four to 139 months). The mean Constant score increased from 31 points preoperatively to 76 points at the time of the latest follow-up (p < 0.0001). Active forward flexion, external rotation, and internal rotation also significantly increased (p < 0.0001). Complications occurred in four patients (15%) and included early loosening of the glenoid component (one patient) and neurologic complications (three patients). No radiolucent lines were observed around the central peg or screws of the glenoid component. Grade-1 or 2 scapular notching was present in ten shoulders (37%). No recurrence of posterior instability was observed. CONCLUSIONS Reverse shoulder arthroplasty for the treatment of primary glenohumeral osteoarthritis in patients with a biconcave glenoid without rotator cuff insufficiency can result in excellent clinical outcomes. Reverse shoulder arthroplasty is a viable surgical option to solve both the problem of severe static posterior glenohumeral instability and severe glenoid erosion.

Hill-Sachs Lesions in Shoulders With Traumatic Anterior Instability Evaluation Using Computed Tomography With 3-Dimensional Reconstruction

Background: In patients with traumatic anterior shoulder instability, a large Hill-Sachs lesion is a risk factor for postoperative recurrence. However, there is no consensus regarding the occurrence and enlargement of Hill-Sachs lesions. Purpose: To investigate the influence of the number of dislocations and subluxations on the prevalence and size of Hill-Sachs lesions evaluated by computed tomography (CT) with 3-dimensional reconstruction. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: The prevalence and size of Hill-Sachs lesions were evaluated preoperatively by CT in 142 shoulders (30 with primary instability and 112 with recurrent instability) before arthroscopic Bankart repair. First, the prevalence of Hill-Sachs lesions was compared with the arthroscopic findings. Then, the size of Hill-Sachs lesions confirmed by arthroscopy was remeasured using the previous CT data. In addition, the relationship of Hill-Sachs lesions with the number of dislocations and subluxations was investigated. Results: Hill-Sachs lesions were detected in 90 shoulders by initial CT evaluation and were found in 118 shoulders at arthroscopy. The Hill-Sachs lesions missed by initial CT were 15 chondral lesions and 13 osseous lesions. However, all 103 osseous Hill-Sachs lesions were detected by reviewing the CT data. In patients with primary subluxation, the prevalence of Hill-Sachs lesions was 26.7%, and the mean length, width, and depth of the lesions (calculated as a percentage of the diameter of the humeral head) were 9.0%, 5.3%, and 2.1%, respectively, while the corresponding numbers for primary dislocation were 73.3%, 27.7%, 14.8%, and 7.0%, all showing statistically significant differences. Among all 142 shoulders, the corresponding numbers were, respectively, 56.3%, 20.7%, 11.2%, and 4.8% in patients who had subluxations but never a dislocation; 83.3%, 33.4%, 19.1%, and 7.6% in patients with 1 episode of dislocation; and 87.5%, 46.8%, 22.2%, and 10.2% in patients with ≥2 episodes, all showing statistically significant differences. There were no differences in lesion measurements in relation to the number of subluxations. Conclusion: Computed tomography is a useful imaging modality for evaluating Hill-Sachs lesions except for purely cartilaginous lesions. Hill-Sachs lesions were more frequent and larger when the primary episode was dislocation than when it was subluxation. Among patients with recurrent episodes of complete dislocation, the prevalence of Hill-Sachs lesions is increased, and the lesions are larger.

Enlargement of Glenoid Defects in Traumatic Anterior Shoulder Instability: Influence of the Number of Recurrences and Type of Sport

Background: Large glenoid rim defects in patients with traumatic anterior shoulder instability are often regarded as a contraindication for arthroscopic Bankart repair, with a defect of 20% to 27% considered as the critical size. While recurrence of dislocations, male sex, and collision sports were reported to be the significant factors influencing large glenoid defects, the influences of subluxations and more detailed types of sports were not investigated. Purpose: To investigate the influence of the number of dislocations and subluxations and type of sport on the occurrence and size of glenoid defects in detail. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 223 shoulders (60 with primary instability, 163 with recurrent instability) were prospectively examined by computed tomography. Glenoid rim morphology was compared between primary and recurrent instability. In patients with recurrent instability, the relationship between the glenoid defect and the number of dislocations and subluxations was investigated. In addition, glenoid defects were compared among 49 male American football players, 41 male rugby players, 27 male baseball players, and 25 female athletes. Results: The mean extent of the glenoid defect was 3.5% in shoulders with primary instability and 11.3% in those with recurrent instability. A glenoid defect was detected in 108 shoulders (66.2%) with recurrent instability versus 12 shoulders (20%) with primary instability. Regarding the influence of the total number of dislocations/subluxations, the average extent of the glenoid defect was 6.3% in 85 shoulders with 2 to 5 events, 12.9% in 34 shoulders with 6 to 10 events, and 19.6% in 44 shoulders with 11 or more events. The glenoid defect became significantly larger along with an increasing number of recurrences. Although recurrent subluxation without dislocation also influenced the glenoid defect size, the number of dislocations did not. The average extent of the glenoid defect was 12.0% in rugby players, 8.9% in American football players, 4.7% in female athletes, and 4.5% in baseball players. Glenoid defects were significantly smaller in male baseball players and female athletes than in male collision athletes. Conclusion: The glenoid defect is significantly enlarged by damage due to recurrent dislocation and subluxation; therefore, glenoid rim morphology differs markedly between primary and recurrent instability. Glenoid defect size is also influenced by sex and by the type of sport.

Influence of posterior capsular tightness on throwing shoulder injury

PurposeThe role of posterior capsular tightness in throwing shoulder injury has not yet been clarified. Accordingly, the influence of posterior capsular tightness on the occurrence of throwing shoulder injury was investigated.MethodsSixty-one shoulders with throwing injury were retrospectively reviewed, including 50 tight shoulders and 11 non-tight shoulders. Occurrence of long head of biceps (LHB) lesions, superior glenohumeral ligament (SGHL) and middle glenohumeral ligament (MGHL) injuries, type 2 SLAP lesions, and supraspinatus and subscapularis tendon injuries was compared between the tight and non-tight groups.ResultsThere were LHB lesions in 8 tight shoulders and 6 non-tight shoulders, SGHL injury in 14 and 8 shoulders, and subscapularis tendon injury in 6 and 5 shoulders, respectively, showing significant differences between tight and non-tight shoulders. In contrast, MGHL injury, type 2 SLAP lesions, and supraspinatus tendon injury showed no significant differences. The SLAP lesion was located anteriorly in 6 tight shoulders, posteriorly in 5, and combined in 4 versus 0, 3, and 0 for the non-tight shoulders, respectively, so anterior SLAP lesions only occurred in tight shoulders. Similarly, anterior supraspinatus tendon injuries had a higher incidence in tight shoulders than in non-tight shoulders (19 vs 3).ConclusionsRotator interval lesions were frequent in non-tight shoulders, while anterior SLAP lesions and anterior supraspinatus tendon injuries were predominant in tight shoulders. The significance of posterior capsular tightness should be reconsidered.Level of evidence Retrospective, Level IV.

Clinical Outcome of Arthroscopic Bankart Repair Combined With Simultaneous Capsular Repair

Background: A capsular tear and humeral avulsion of the glenohumeral ligament lesion are not uncommon findings in association with a Bankart lesion. However, there have been few reports regarding the prevalence of such capsular lesions and the postoperative recurrence after capsular repair. Purpose/Hypothesis: This study investigated the prevalence of capsular lesions and clarified their influence on the postoperative recurrence of instability. In addition, factors were identified that were associated with the occurrence of capsular lesions and the postoperative recurrence of instability. We hypothesized that clinical outcomes would be improved by combining arthroscopic Bankart repair with simultaneous capsular repair. Study Design: Cohort study; Level of evidence, 3. Methods: Capsular lesions were retrospectively examined through operative records, still pictures, and videos in 172 shoulders with traumatic anterior instability. First, the prevalence of capsular lesions and their severity were investigated. Then, postoperative recurrence was determined in shoulders observed for a minimum of 2 years. Finally, factors were assessed that were associated with the occurrence of capsular lesions and the postoperative recurrence of instability. Results: A capsular lesion was recognized in 37 shoulders (21.5%), being severe and mild in 20 and 17, respectively. All were repaired simultaneously with the arthroscopic Bankart procedure. After follow-up for at least 2 years, recurrence of instability was detected in 10 of 34 shoulders (29.4%), including 6 (31.6%) with severe capsular lesions and 4 (26.7%) with mild lesions. The recurrence rate was significantly higher in shoulders with a capsular lesion than in shoulders without a capsular lesion (18 of 120, 15%; P = .013), but there was no significant difference between severe and mild lesions. Regardless of the sport played, capsular lesions were significantly more frequent in patients ≥30 years old, patients with complete dislocation, and patients with a coexisting Hill-Sachs lesion. Postoperative recurrence of instability was significantly more frequent in patients <30 years and competitive athletes. Conclusion: In shoulders undergoing arthroscopic Bankart repair, capsular lesions were often present and were associated with higher postoperative recurrence of instability. While these lesions were more frequent in older patients, postoperative recurrence of instability was more likely in young competitive athletes.

Transosseous-Equivalent Arthroscopic Bankart Repair by Twin Anchor Footprint Fixation (TAFF) Technique Using JuggerKnot™ Soft Anchor

In 2004, we developed a new type of arthroscopic Bankart repair technique named the double anchor footprint fixation (DAFF), using two different suture anchors for the glenoid neck and glenoid surface anchors, to achieve a more anatomic and wider footprint fixation. As soon as the small, all-suture soft anchor was available in 2011, the twin anchor footprint fixation (TAFF) technique was developed using only the soft anchor for both the glenoid neck and glenoid surface anchors. This TAFF technique might be suitably indicated for patients with a significant ALPSA (anterior labro ligamentous periosteal sleeve avulsion) lesion or those who need capsular shift. Moreover, the specific indications of this technique are revision cases after conventional arthroscopic Bankart repair surgery, and a bony Bankart lesion with large thick bone fragments. The TAFF technique using the all-suture soft anchors is a step closer to a true transosseous suture technique, which is the conventional open procedure making a bone tunnel.