Treatment of chronic glenoid defects in the setting of recurrent anterior shoulder instability: a systematic review

The Arthroscopic Bristow Procedure Is Superior to the Arthroscopic Latarjet Procedure in Return to Sports but Inferior in Graft Healing: A Comparative Study With 3.4-Year Follow-Up

PURPOSE

To compare clinical and computed tomography outcomes between the arthroscopic Latarjet procedure and the arthroscopic Bristow procedure.

METHODS

Patients who underwent arthroscopic Latarjet or Bristow procedures with at least 2 years of follow-up were retrospectively reviewed. Thirty-eight shoulders were included in the Latarjet group, and 34 were included in the Bristow group. Recurrence of dislocation, clinical scores, rate of return to sports (RTS), and computed tomography assessment findings (position of transferred coracoid, graft healing, graft absorption, and glenohumeral degenerative osteoarthritis [OA]) were obtained at final follow-up.

RESULTS

No recurrent dislocation occurred in either group, and no significant differences in clinical scores were found between the 2 procedures, with a mean follow-up period of 3.4 years. The operative time in the Bristow group was significantly shorter than that in the Latarjet group (P < .001). The transferred coracoid had healed in 94.7% of the patients in the Latarjet group and 85.3% in the Bristow group at final follow-up (P = .01). No significant difference in graft absorption or the degree of glenohumeral OA was detected between the 2 groups. However, moderate to severe OA only occurred in the Latarjet group at final follow-up (4 of 38 shoulders, 10.5%). The postoperative external rotation angle and level of RTS favored the Latarjet procedure (P = .030 and P = .034, respectively).

CONCLUSIONS

Both the arthroscopic Latarjet and arthroscopic Bristow procedures led to good clinical scores with no new dislocation episodes. The Bristow group showed significantly less graft healing than the Latarjet group. However, the arthroscopic Bristow procedure took less operative time and showed a lower rate of early moderate to severe glenohumeral OA, better range of motion, and a higher rate of RTS.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

Recurrent Anterior Shoulder Dislocation After Trauma with Coracoid Apophysis Fracture - A Rare Association

Anterior dislocations represent about 96% of total shoulder dislocations, with recurrence/instability being more common in young patients. Injury of other shoulder structures is frequent, namely bony Bankart lesion. However, the association with coracoid apophysis fracture is very rare. The present article describes the clinical case of a 67-year-old man who presented to the emergency department with complaints of persistent omalgia, with acute episodes, beginning after a fall from his own height. The patient also presented history of shoulder trauma 3 months earlier, which was evaluated at another hospital. Shoulder anterior dislocation was observed radiographically, and the computed tomography (CT) confirmed bone erosion of the anteroinferior part of the glenoid (bone loss of about 50% of the anteroposterior diameter in the lower region of the glenoid), with almost complete resorption of the bony Bankart lesion (apparent in later analysis of the radiography of the initial traumatic episode). Connectedly, a transverse fracture of the coracoid apophysis (type II in the Ogawa classification) was diagnosed. The patient was submitted to surgical treatment, with anterior bone stop confection using the remnant of the fractured fragment of the coracoid supplemented by tricortical autologous iliac graft, fixed with cannulated screws (according to the Bristow-Latarjet and Eden-Hybinett techniques). In the postoperative follow-up, a good functional result was observed, with no new episodes of dislocation and no significant pain complaints. A rare association of shoulder lesions is described, and the challenge of their treatment is highlighted, given the late diagnosis, as in the case presented.

Glenoid Bone Loss Pattern in Patients With Posterior Instability Versus Anterior Instability: A Matched Cohort Study

Background

The pattern of glenoid bone loss (GBL) in anterior glenohumeral instability is well described. It was recognized recently that posterior GBL after instability has a posteroinferior pattern.

Purpose/Hypothesis

The purpose of this study was to compare GBL patterns in a matched cohort of patients with anterior versus posterior glenohumeral instability. The hypothesis was that the GBL pattern in posterior instability would be more inferior than the GBL pattern in anterior instability.

Study Design

Cohort study; Level of evidence, 3.

Methods

In this multicenter retrospective study, 28 patients with posterior instability were matched with 28 patients with anterior instability by age, sex and number of instability events. GBL location was defined using a clockface model. Obliquity was defined as the angle between the long axis of the glenoid and a line tangent to the GBL. Superior and inferior GBL were measured as areas and defined relative to the equator. The primary outcome was the 2-dimensional characterization of posterior versus anterior GBL. The secondary outcome was a comparison of the posterior GBL patterns in traumatic and atraumatic instability mechanisms in an expanded cohort of 42 patients.

Results

The mean age of the matched cohorts (n = 56) was 25.2 ± 9.87 years. The median obliquity of GBL was 27.53° (interquartile range [IQR], 18.83°-47.38°) in the posterior cohort and 9.28° (IQR, 6.68°-15.75°) in the anterior cohort (P < .001). The mean superior-to-inferior bone loss ratio was 0.48 ± 0.51 in the posterior cohort and 0.80 ± 0.55 (P = .032) in the anterior cohort. In the expanded posterior instability cohort (n = 42), patients with traumatic injury mechanism (n = 22), had a similar GBL obliquity compared to patients with an atraumatic injury mechanism (n = 20) (mean, 27.73° [95% CI, 20.26°-35.20°] vs 32.20° [95% CI, 21.27°-43.14°], respectively) (P = .49).

Conclusion

Posterior GBL occurred more inferiorly and at an increased obliquity compared with anterior GBL. This pattern is consistent for traumatic and atraumatic posterior GBL. Bone loss along the equator may not be the most reliable predictor of posterior instability, and critical bone loss may be reached more rapidly than a model of loss along the equator may predict.

Dynamic Anterior Stabilization of the Shoulder With Adjustable-Loop Device

Dynamic anterior stabilization of the shoulder is a surgical procedure based on a triple soft-tissue block. This procedure is designed to fit within a gray zone between the Bristow-Latarjet procedure and the Bankart procedure, where the patient would not need a bone graft; however, capsular reconstruction alone may be insufficient to yield reliable stabilization. This article describes dynamic anterior stabilization of the shoulder using the adjustable-loop device.

Biomechanical Strength of Screw Versus Suture Button Fixation in the Latarjet Procedure: A Cadaver Study

We compared the strength of screw vs suture button fixation in the Latarjet procedure for shoulder dislocation through biomechanical testing in a cadaver model. Cadavers were assigned randomly to receive screw or suture button fixation (both groups, n=5). The anteroposterior radius of the glenoid was measured, and a bony defect was created on the anteroinferior rim of the glenoid, equal to 25% of the width of the anteroposterior radius of the glenoid surface. The coracoid process was transferred into the newly created bony defect of the glenoid and fixed with two 3.5-mm partially threaded cannulated screws or 2 surgical buttons. All samples underwent tensile testing in the anteroinferior direction. Statistical analysis was performed to compare mean forces at failure between groups (alpha=.05). The mean force at failure was higher in the screw group (295 N; range, 103-534 N) than in the suture button group (133 N; range, 74-270 N) (P=.045). We found no difference between groups in ability to withstand a force of 150 N, which is the reported mean daily force threshold borne by the shoulder (P=.52). Screw fixation withstood a higher failure load than suture button fixation, indicating that screw fixation is a biomechanically superior option in the Latarjet procedure. The fixation methods did not differ in their ability to withstand the mean force borne by the shoulder during activities of daily living; thus, suture button fixation should be considered as an option in the Latarjet procedure. [Orthopedics. 2022;45(6):e321-e325.].

Comparison of two coracoid process transfer techniques on stress shielding using three-dimensional finite-element model

Background

We created patient-based 3D finite-element (FE) models that simulate the congruent-arc Latarjet (CAL) and traditional Latarjet (TL) procedures and then compared their stress distribution patterns with different arm positions and glenoid defects.

Methods

The computed tomography data of 10 adult patients (9 men and 1 woman, ages: 18–50 years) were used to develop the 3D FE glenohumeral joint models. Twenty-five and 35% bony defects were created on the anterior glenoid rim, and the coracoid process was transferred flush with the glenoid by the traditional and congruent-arc techniques using two half-threaded screws. A load was applied to the greater tuberosity toward the center of the glenoid, and a tensile force (20 N) was applied to the coracoid tip along the direction of the conjoint tendon. The distribution patterns of the von Mises stress in the traditional and congruent-arc Latarjet techniques were compared.

Results

The mean von Mises on the graft was significantly greater for the TL technique than for the CAL. While the von Mises stress was greater in the distal medial part of the graft in the TL models, a higher stress concentration was observed in the distal lateral edge of the coracoid graft in the CAL models. The proximal medial part of the graft exhibited significantly lower von Mises stress than the distal medial part when compared according to technique, defect size, and arm position. Increasing the glenoid defect from 25 to 35% resulted in a significant increase in stress on the lateral side of the graft in both models.

Conclusion

The stress distribution patterns and stress magnitude of the coracoid grafts differed according to the procedure. Due to placing less stress on the proximal–medial part of the graft, the CAL technique may lead to insufficient stimulation for bone formation at the graft–glenoid interface, resulting in a higher incidence of graft osteolysis.

Clinical relevance The CAL technique may lead to a higher incidence of graft osteolysis.

Level of evidence

Basic Science Study; Computer Modeling.

Remplissage for Anterior Shoulder Instability: History, Indications, and Outcomes

Remplissage is a nonanatomic capsulotenodesis of the infraspinatus tendon used to fill engaging or "off-track" Hill-Sachs lesions in patients at high risk of recurrent instability with isolated Bankart repair. Indications for remplissage are expanding, as the importance of subcritical bone loss and the glenoid track on patient outcomes and recurrence rates continues to be investigated. Remplissage is also suggested in patients at high risk of recurrent instability following isolated anterior labral repair, such as collision and contact athletes with Hill-Sachs lesions that have not reached the threshold of "off track." Multiple arthroscopic remplissage techniques exist including, more recently, knotless techniques.

Clinical and Radiographic Outcomes After Arthroscopic Inlay Bristow Surgery With Screw Versus Suture Button Fixation: A Comparative Study of 117 Patients With 3.3-Year Follow-up

Background:

Some studies have advocated the use of suture button fixation during Bristow-Latarjet surgery to reduce complications associated with screw fixation. However, data comparing these fixation methods are relatively incomplete.

Purpose:

To investigate the efficacy of modified arthroscopic Bristow-Latarjet surgery and compare the clinical and radiographic outcomes using screw versus suture button fixation.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

We evaluated 136 patients with traumatic anterior shoulder instability who underwent the modified arthroscopic Bristow-Latarjet surgery between June 2015 and February 2018. Of these patients, 117 who met the inclusion criteria were enrolled at a mean follow-up of 3.3 ± 0.7 years. Shoulders were separated into 2 groups based on fixation technique: screw fixation (group A; n = 63) or suture button fixation (group B; n = 54). Computed tomography imaging findings and clinical results were assessed preoperatively; immediately after operation; and postoperatively at 3 months, 6 months, 1 year, and final follow-up.

Results:

There were no significant differences between the groups in terms of postoperative clinical scores, the level of return to sports, range of motion, graft position, or reoperation rates. Bone healing was observed in 97.4% of the cases overall (114/117), with 98.4% bone union in group A and 96.3% in group B at final follow-up. Bone absorption was more common in group A (n = 30; 47.6%) compared with group B (n = 10; 18.5%) (P = .003). There were no hardware-related complications in group B, compared with 7.9% of patients in group A (P = .034). One patient in group B had a recurrent dislocation due to an unexpected event, and there were no recurrent dislocations in group A.

Conclusion:

After the modified arthroscopic Bristow-Latarjet procedure, both suture button and screw fixation methods demonstrated high bony healing rates and low risk of recurrence. Less coracoid graft resorption and no hardware-related complications were seen with suture button fixation.

Long-term outcomes of open modified inferior capsular shift for traumatic anterior shoulder instability: over 20 years of follow-up

BACKGROUND

This study aimed to assess the long-term outcomes of the open modified inferior capsular shift procedure across more than 20 years in patients with traumatic anterior shoulder instability.

METHODS

Participants in this study comprised 84 patients (86 shoulders; 67 men, 17 women). Mean follow-up was 28.0 years. We compared the recurrent instability rate after surgery, apprehension, revision rate, satisfaction, return to preinjury sporting activity, and patient background characteristics between recurrent and nonrecurrent groups. Twenty-seven patients who were examined directly were evaluated for differences in range of motion and muscle strength between affected and nonaffected sides. Clinical outcome scores used for this study were the Western Ontario Shoulder Instability Index and the Rowe score.

RESULTS

Nine shoulders (10.5%) showed recurrent instability, as dislocation in 3 shoulders and subluxation in 6 shoulders, but no revisions were required. All patients with recurrent instability were males with new trauma. Three shoulders developed recurrent instability ≤5 years after surgery, and the remaining 6 shoulders showed recurrent instability >5 years after surgery. No significant differences in any patient characteristic were identified between the recurrent and nonrecurrent groups. Significant differences between affected and nonaffected sides were seen in the mean active range of motion or muscle strength for external rotation in the anatomic position or in 90° of abduction. Western Ontario Shoulder Instability Index and Rowe score were significantly worse in the recurrent group than in the nonrecurrent group. Patients reported that 84 shoulders (97.7%) were "much better." Most athletes (88.4%) had returned to sports activity at a level >70%.

CONCLUSION

We investigated long-term outcomes of the open modified inferior capsular shift procedure for traumatic anterior shoulder instability. Our data suggest that recurrent instability might result from new trauma even if a long time has passed since the open modified inferior capsular shift procedure, so follow-up should be continued as long as possible after surgery. As in other reports, satisfaction was high and clinical scores were good. We thus believe this surgical method offers good results even after more than 20 years.

Evolving Concepts in the Management of Shoulder Instability

BACKGROUND

Shoulder instability exists on a spectrum ranging from subtle subluxation and pain to dislocation and can be the result of a traumatic event or repetitive microtrauma. Shoulder instability can result in significant disability and often requires surgical intervention, especially amongst younger, active patient populations. The optimal treatment of shoulder instability depends on the degree of instability and concomitant pathology involving the labrum, capsule, and bony anatomy of the glenoid and humeral head. Even with surgical intervention, recurrent instability remains a relatively common and difficult problem to address.

PURPOSE

With a focus on anterior instability, the purpose of this review article is to discuss the current assessment and treatment of shoulder instability, and highlight current and future treatment modalities, as well as to identify current trends and deficiencies in our current management. We also provide an algorithm for the surgical treatment of anterior shoulder instability.

METHODS

Literature databases were extensively searched for recent articles related to the mechanism, diagnosis, and treatment of shoulder instability to comprise a comprehensive review.

CONCLUSION

Although there are multiple treatment modalities available for shoulder instability, such as nonoperative management, open and arthroscopic Bankart repair, Latarjet procedures, and remplissage, orthopaedic surgeons continue to learn about the most appropriate method of management as increasing long-term outcomes become available.

Double-screw and quadruple-button fixation for the glenoid: Latarjet versus bone block applications

Background

The Latarjet and bone block procedures can be secured with screws or cortical buttons. The purpose of this biomechanical study was to compare quadruple buttons vs. double screws for fixation of anterior glenoid bone grafts.

Methods

Twelve cadaveric scapulae (6 pairs) were denuded, resected, and potted. Pairs were randomized to quadruple-button or double-screw fixation after creation of a 15% anterior glenoid defect. The specimens underwent cyclic uniaxial compressive glenoid loading between 50 and 200 N for 1000 cycles at 1 Hz. Testing was repeated for conjoint tendon loads of 0 N (simulating a bone block procedure), 10 N, and 20 N (simulating a Latarjet procedure). Peak resultant relative coracoid graft displacement was optically tracked at 3 points (superior, central, and inferior) on the edge of the coracoid.

Results

No significant differences were found between buttons and screws for bone block applications or with 10 N of conjoint tendon loading (P ≥ .095). At 20 N of conjoint tendon loading, however, the screws were significantly more stable than the buttons (P ≤ .023). During the initial 20-N conjoint load application, all 3 points displaced significantly more with the button reconstruction than with the screws (P ≤ .01). Overall, mean displacements did not exceed 1 mm at any position on the coracoid, regardless of testing condition.

Conclusions

The quadruple-button technique is comparable to screws when the coracoid is used as a bone block or when conjoint tendon loading is minimized. However, at higher conjoint tendon loads, the screws produced a more stable coracoid graft than the buttons.

Distal clavicle autograft for anterior-inferior glenoid augmentation: A comparative cadaveric anatomic study

INTRODUCTION

The aim of this study was to anatomically compare distal clavicle and coracoid autografts and their potential to augment anterior-inferior glenoid bone loss.

METHODS

Ten millimeters of distal clavicle and 20 mm of coracoid were harvested bilaterally from 32 cadavers. Length, weight, and height were measured and surface area and density were calculated. For each graft, ipsilateral measurements were compared and the ability to restore corresponding glenoid bone loss was calculated.

RESULTS

Distal clavicle grafts were larger than coracoid grafts with respect to length (22.3 mm versus 17.7 mm; p < 0.001), height (12.49 mm versus 9.65 mm; p < 0.001), mass (2.72 g versus 2.45 g; p = 0.0437), and volume (2.36 cm³ versus 1.96 cm³; p = 0.002). Coracoid grafts had larger widths (14.56 mm versus 10.52 mm; p < 0.001) and greater density (1.24 g/cm³ versus 1.18 g/cm³; p < 0.001). Distal clavicle surface area was greater on both the articular (2.93 cm² versus 1.5 cm²; p < 0.001) and superior surfaces (2.76 cm² versus 1.5 cm²; p < 0.001) when compared to lateral coracoid surface area.

DISCUSSION

Distal clavicle grafts were larger and restored larger bony defects but had greater variability and lower density than coracoid grafts. Clinical studies are needed to compare these graft options.

Mathematical modeling of glenoid bone loss demonstrate differences in calculations that May affect surgical decision making

Objective

Two glenoid bone loss calculations are compared across a range of anatomic glenoid sizes.

Methods

20 cadaveric paired glenoid diameters were measured to create glenoid models with bone loss calculated in 1 mm linear increments up to 50% bone loss comparing the linear measurement percentage (LMP) to the circle line method (CLM) gold standard.

Results

The LMP overestimates glenoid bone loss at every potential 1 mm increment across each glenoid model until bone loss reaches 50%.

Conclusion

The widely-used LMP method overestimates bone loss compared to a gold standard potentially misguiding surgeons towards bony reconstruction in shoulder instability during preoperative planning.

Effects of Glenoid and Humeral Bone Defects on Recurrent Anterior Instability of the Shoulder

For proper treatment of recurrent anterior instability of the shoulder with a bone defect, the defect size should be assessed preoperatively with three-dimensional computed tomography or magnetic resonance imaging. In general, the risk of postoperative recurrence of instability is estimated on the basis of preoperative imaging of bipolar bone defects: more than 20%–25% glenoid bone loss and off-track Hill-Sachs lesions have been considered risk factors for recurrence. In patients with a glenoid bone defect more than 20%–25%, a bone graft procedure, such as the Latarjet procedure, is preferred regardless of the glenoid track concept, because compared with arthroscopic stabilization procedure, it provides greater postoperative stability. For patients with a borderline glenoid bone defect (around 20%), surgeons should discuss surgical options with the patients, considering their demand and physical activity level. In addition, the surgeon should take care to prevent postoperative instability and long-term complications. Arthroscopic soft-tissue reconstruction including labral repair and capsular plication combined with the additional remplissage procedure is an anatomical procedure and could be considered as one of the primary treatment methods for patients with glenoid bone defects around 20%. Therefore, treatment strategies for recurrent anterior shoulder instability combined with bone defects should be determined more flexibly on the basis of the patient's individual condition.

How to handle minor and major bone loss in the shoulder? Current concepts

Anterior shoulder instability is a significant problem in orthopaedic surgery. It carries a heavy burden on quality of life, especially in young, active patients. Surgical treatment is therefore often carried out in this population. Several strategies can effectively address this issue. Yet, the consensus is lacking on the parameters which favour one technique over another, especially when bone loss is present. This is because of the complex, dynamic interplay between bone loss on the humeral side (ie, Hill-Sachs lesion) and glenoid bone loss, which is a common occurrence and defined as ‘bipolar’. There is an ongoing debate over the percentage of glenoid bone loss warranting bone block procedures: 13.5–15% is an indicator for such procedures (ie, Latarjet), although this value is still considered controversial and not uniformly accepted. A multitude of other factors (ie, age, sex, level of activity and so on) come into play alongside bipolar bone loss and the weight of each factor has yet to be fully elucidated. Also, refining the algorithm for the right procedure in the right patients will reduce the number of side effects stemming from initial, suboptimal treatment choice. Knowing how to manage previous surgical treatment failure is also key for the treating orthopaedic surgeon, who must be able to address the root cause of failure and react accordingly and effectively. This paper analyses key factors in treatment choice, the current stance of the literature on varying degrees of bone loss and choices on surgical treatment failure, lack of evidence and need for future research.

Revision of failed Latarjet with the Eden-Hybinette surgical technique

INTRODUCTION

The outcomes of the Latarjet procedure for anterior shoulder instability are highly satisfactory although recurrences are possible. Surgical revision is challenging, and often requires an iliac crest bone graft as described by Eden and Hybinette. The aims of our study were to analyze the outcomes of the Eden-Hybinette technique after failed Latarjet procedure, determine the failure and complication rates, and analyze the risk of osteoarthritis. We hypothesized that the Eden-Hybinette technique would yield good outcomes after failed Latarjet procedure.

MATERIAL AND METHODS

Retrospective multicenter study (9 hospitals) by the French Shoulder and Elbow Society (SoFEC) involving 46 patients who underwent revision surgery with an Eden-Hybinette procedure after failed Latarjet stabilization. The patients had a minimum follow-up of 1year and the outcomes were evaluated based on the Rowe score, Walch-Duplay score and radiographs.

RESULTS

The mean age at the final assessment was 32years. The mean follow-up was 38 months and 86% of patients had a stable shoulder with an overall satisfaction rate of 80%. Postoperatively, the Rowe score averaged 76/100 and the Walch-Duplay score averaged 68/100; 60% of patients had resumed their sports participation. Return to sport was statistically correlated with age (p=0.0001), osteoarthritis (p=0.05) and time elapsed between the two surgical procedures (p=0.0001). The Rowe score was statistically correlated with osteoarthritis (p=0.01).

DISCUSSION/CONCLUSION

Our study is one of the largest on the Eden-Hybinette procedure for recurrent anterior shoulder instability. The outcomes at 3years' follow-up were satisfactory in 80% of patients and 86% had stable shoulders. The osteoarthritis rate was low (11%), although the follow-up period was relatively short.

LEVEL OF EVIDENCE

IV, non-randomized multicenter retrospective study.

The Effect of Screw Design and Cortical Augmentation on Insertional Torque and Compression in Coracoid-Glenoid Fixation in a Sawbones Model

PURPOSE

To compare screw insertional torque and coracoid-glenoid compression from 4 fixation techniques with different screw design parameters and cortical augmentation for the Latarjet procedure.

METHODS

Simulated Latarjet procedures were performed with 4 fixation techniques using laminated polyurethane blocks with dimensions similar to the coracoid-glenoid construct. The groups included DePuy Synthes Mitek 3.5-mm partially threaded screws with top hats, Arthrex 3.75-mm fully threaded screws with a 2-hole plate, Arthrex 3.75-mm fully threaded screws, and Smith & Nephew 4.0-mm partially threaded screws. Screws were inserted using a digital torque-measuring screwdriver to determine maximum insertional torque. Pressure-sensitive film was used to measure the maximum contact pressure and the effective pressure distribution (EPD) between the coracoid and glenoid; the EPD represents the percentage of the film's surface area that experienced pressure greater than 10 MPa. One-way analysis of variance and post hoc tests were used for statistical analysis.

RESULTS

Significant differences were found between the 4 fixation groups for each variable measured. The 2 cortically augmented systems produced significantly higher maximum insertional torque than the non-cortically augmented systems (P < .001 for both). The 3.75-mm screws with a 2-hole plate yielded significantly higher contact pressures than the 4.0-mm screws (P = .028). This group also had a high EPD, with a mean value more than double the values of the non-cortically augmented systems (P = .037 and P < .001).

CONCLUSIONS

Cortically augmented fixation methods showed higher maximum insertional torque, maximum contact pressure, and EPD between the surfaces of the coracoid and glenoid in this Sawbones model.

CLINICAL RELEVANCE

Various implants are available for the Latarjet procedure, but their biomechanical characteristics have not yet been fully elucidated. Graft fracture and nonunion represent 2 modes of failure that may be related to insertional torque and coracoid-glenoid compression. This study compared screw insertional torque and compression achieved using 4 fixation techniques with different screw design parameters and cortical augmentation in a Sawbones model.

Relationship between the Thickness of the Coracoid Process and Latarjet Graft Positioning-An Anatomical Study on 70 Embalmed Scapulae

Background: The Latarjet procedure is a popular technique with the aim of the reconstruction of glenoid cavity bone defects in patients with chronic anterior shoulder instability. Studies have shown that the Congruent arc Latarjet procedure is better able to reconstruct larger defects than the Classic Latarjet, but there is a lack of information on the limitations of both methods. Methods: The dimensions of the glenoid width and the native coracoid process of two groups with 35 Formol-Carbol embalmed scapulae each were measured using a digital caliper. The relationship between the coracoid graft and the anterior-posterior diameter of the glenoid cavity was calculated to determine the maximum defect size of the glenoid cavity width, which can be treated by both Latarjet techniques. Results: The average restorable defect size of the anterior segment of the glenoid cavity was 28.4% ± 4.6% (range 19.2%–38.8%) in the Classic Latarjet group, and 45.6% ± 5.2% (range 35.7%–57.1%) in the Congruent arc Latarjet group. Based on our results, the feasibility of the Classic Latarjet procedure to reconstitute the anatomical width of the glenoid cavity was 86% in a 25% bone loss scenario, and only 40% in a 30% bone loss scenario. Conclusion: Based on our results we are unable to define a clear threshold for the optimal Latarjet graft position. In glenoid cavity defects <20%, the Classic Latarjet technique usually provides enough bone stock for anatomical reconstruction. Defects ≥35% of the glenoid cavity width should only be treated with a coracoid graft in the Congruent arc position. In the critical area between 20% and 35% of bone loss, we suggest the preoperative assessment of coracoid dimensions, based on which the graft position can be planned to restore the anatomical anterior-posterior diameter of the glenoid cavity.

All-arthroscopic, guided Eden-Hybbinette procedure using suture-button fixation for revision of failed Latarjet

PURPOSE

To report the results of a guided arthroscopic Eden-Hybbinette procedure, using suture button for iliac crest bone graft fixation, in a series of patients with a prior failed Latarjet and persistent glenoid bone loss.

METHODS

Seven consecutive patients (5 males, 2 females, mean age: 30.7 years [range, 17-47 years]) with recurrent anterior dislocations and glenoid deficiency greater than 20% underwent the all-arthroscopic revision procedure. The iliac crest bone graft and suture-button device (Bone-Link) were shuttled through the rotator interval. Specific drill guides were used and a suture tensioning device allowed bone graft compression. Previous broken screw shafts (3 patients) were left in situ. Graft placement and healing was assessed postoperatively with computed tomography imaging.

RESULTS

No neurologic injury or hardware problems occurred, and no patient required further surgery. On computed tomography scan, optimal positioning (flush and under the equator) and healing of the bone graft was observed in all patients. At a mean follow-up of 21 months (range, 12-39 months), all but one patient were satisfied and had a stable shoulder; 5 returned to sports. The Constant score increased from 32 to 81 points, and the subjective shoulder value from 31% to 87% (P < .001). The Walch-Duplay and Rowe scores averaged 85.7 (range, 65-100) points and 86.4 (range, 70-100) points, respectively.

CONCLUSION

Recurrence of anterior shoulder instability after a failed Latarjet procedure can be successfully treated by an all-arthroscopic Eden-Hybbinette procedure. Suture-button fixation is reliable and permits optimal positioning and predictable healing of the new bone graft; in addition, it is an appropriate fixation option in the setting of retained broken hardware.

Demographics and Distal Tibial Dimensions of Suitable Distal Tibial Allografts for Glenoid Reconstruction

PURPOSE

To evaluate whether characteristics such as age, height, weight, sex, or body mass index affected the distal tibial dimensions and radius of curvature (ROC) of a potential donor for anterior glenoid augmentation.

METHODS

A retrospective review of magnetic resonance imaging of ankles without bony trauma was performed, and the anteroposterior (AP) and medial-lateral (ML) distances and ROC of the tibial plafond articular surface were measured. Demographic characteristics, including age, sex, height, weight, and body mass index, were recorded.

RESULTS

A total of 141 imaging studies were included (73 men and 68 women; average age, 38.2 ± 12.65 years). All potential specimens accommodated harvest of a 10 × 22-mm distal tibial allograft bone block. Men had greater ML (42.74 cm [95% confidence interval (CI), 42.09-43.39 cm] vs 38.01 cm [95% CI, 37.30-38.72 cm]; P < .001) and AP (38.16 cm [95% CI, 37.47-38.85 cm] vs 34.57 cm [95% CI, 33.97-35.17 cm]; P < .001) dimensions. Significant moderately positive correlations were found for AP dimensions with height (r = 0.584, P < .001) and weight (r = 0.383, P < .001) and for ML dimensions with height (r = 0.711, P < .001) and weight (r = 0.467, P < .001). ROC was positively correlated with height (r = 0.509, P < .001) and weight (r = 0.294, P < .001). Patient age was not related to either the AP or ML distal tibial dimensions or ROC.

CONCLUSIONS

After magnetic resonance imaging analysis, all potential donors permitted harvest of a standard-sized distal tibial allograft irrespective of sex or common anthropometric measures, and 85.8% showed distal tibial morphology acceptable for glenoid augmentation. AP and ML graft dimensions and ROC correlated significantly with height and weight.

LEVEL OF EVIDENCE

Level II, diagnostic study.

The Long Head of the Biceps Bristow-Bankart Procedure for Anterior Shoulder Instability

Surgical procedures to treat anterior shoulder instability are basically split into 2 groups: those for patients with important bone loss and those for patients with no bone loss. However, there is a gray zone between these procedures in which a bone graft would not be needed but bone grafting would result in a desirable improvement in stabilizing mechanisms. We describe a technique based on the triple soft-tissue block, Bankart reconstruction, and long head of the biceps tenodesis at the anterior glenoid rim. The long head of the biceps would add an anterior restrictor by itself, as well as by tensioning the inferior part of the subscapularis.

Effects of Rehabilitation in Bankart Lesion in Non-athletes: A Report of Three Cases

A Bankart lesion is a common traumatic sports injury of the glenohumeral joint. When the shoulder is dislocated, the connective tissue surrounding the joint may tear or rupture. This study aimed to describe the initial dislocation, treatment, medical treatment, rehabilitation outcomes at 3 and 8 months, and return to daily life for three patients. Patient 1 was a 28-year-old male office worker who enjoyed fitness and weight training. His injury was sustained by a fall from his bicycle and subsequent performance of pull-up exercises. Surgery was recommended for repair of the anterior and inferior labrum tear. Reassessment of the surgery was performed after 2 months of rehabilitation. The patient was asked to exercise once a week at a rehabilitation center and to perform home-based exercises. In the first 2 months, the main exercise consisted of range of motion (ROM) exercises and stretching. Thereafter, muscle strengthening, using tubing, equipment and body weight exercises, and proprioceptive exercises were performed to gradually improve muscle strength and for return to daily activities. ROM progressively increased, with recovery of normal range at 2 months post-surgery. However, pain decreased only slightly, with a visual analog score of 6 out of 10 at 2 months post-surgery. At 8 months, the pain was bearable, without causing discomfort. Muscle strength remained almost unchanged initially but gradually recovered, although with a residual deficit of 20–30% in flexion, adduction and internal rotation. Considering the prolonged rehabilitation after surgery, future studies are warranted to analyze the long-term effects of non-surgical therapies by accumulating more cases and developing effective exercise rehabilitation programs.

Prospective Evaluation of Glenoid Bone Loss After First-time and Recurrent Anterior Glenohumeral Instability Events

BACKGROUND

Determining the amount of glenoid bone loss in patients after anterior glenohumeral instability events is critical to guiding appropriate treatment. One of the challenges in treating the shoulder instability of young athletes is the absence of clear data showing the effect of each event.

PURPOSE

To prospectively determine the amount of bone loss associated with a single instability event in the setting of first-time and recurrent instability.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

The authors conducted a prospective cohort study of 714 athletes surveilled for 4 years. Baseline assessment included a subjective history of shoulder instability. Bilateral noncontrast shoulder magnetic resonance imaging (MRI) was obtained for all participants with and without a history of previous shoulder instability. The cohort was prospectively followed during the study period, and those who sustained an anterior glenohumeral instability event were identified. Postinjury MRI with contrast was obtained and compared with the screening MRI. Glenoid width was measured for each patient's pre- and postinjury MRI. The projected total glenoid bone loss was calculated and compared for patients with a history of shoulder instability.

RESULTS

Of the 714 athletes (1428 shoulders) who were prospectively followed during the 4-year period, 22 athletes (23 shoulders) sustained a first-time anterior instability event (5 dislocations, 18 subluxations), and 6 athletes (6 shoulders) with a history of instability sustained a recurrent anterior instability event (1 dislocation, 5 subluxations). On average, there was statistically significant glenoid bone loss (1.84 ± 1.47 mm) after a single instability event ( P < .001), equivalent to 6.8% (95% CI, 4.46%-9.04%; range, 0.71%-17.6%) of the glenoid width. After a first-time instability event, 12 shoulders (52%) demonstrated glenoid bone loss ≥5% and 4 shoulders, ≥13.5%; no shoulders had ≥20% glenoid bone loss. Preexisting glenoid bone loss among patients with a history of instability was 10.2% (95% CI, 1.96%-18.35%; range, 0.6%-21.0%). This bone loss increased to 22.8% (95% CI, 20.53%-25.15%; range, 21.2%-26.0%) after additional instability ( P = .0117). All 6 shoulders with recurrent instability had ≥20% glenoid bone loss.

CONCLUSION

Glenoid bone loss of 6.8% was observed after a first-time anterior instability event. In the setting of recurrent instability, the total calculated glenoid bone loss was 22.8%, with a high prevalence of bony Bankart lesions (5 of 6). The findings of this study support early stabilization of young active patients after a first-time anterior glenohumeral instability event.

Autologous Tricortical Iliac Bone Graft for Failed Latarjet Procedures

The high recurrence rates seen in open and arthroscopic Bankart repair in the presence of significant glenoid bone loss, Hill-Sachs lesions, or combined bony deficiencies have led many surgeons to choose bony reconstructions to manage these injuries. Although the Latarjet procedure has proved to be reliable to manage recurrent anterior shoulder instability, there have been concerns of a higher surgical complication rate associated with this procedure. Moreover, some of the complications reported with this procedure such as symptomatic implants, fracture or nonunion of the coracoid graft, and recurrence of instability could need a revision surgery to be solved. The autologous tricortical iliac bone graft is an excellent option for failed bony reconstructions. However, as with any successful surgery, each step requires planning and precise application to limit risks and avoid pitfalls. This Technical Note provides a detailed description of the autologous tricortical iliac bone graft for failed Latarjet procedures.

Comparative Systematic Review of Fixation Methods of the Coracoid and Conjoined Tendon in the Anterior Glenoid to Treat Anterior Shoulder Instability

BACKGROUND

Coracoid process transfer for the treatment of recurrent glenohumeral dislocations is a safe and reliable procedure; however, there is no consensus as to which is the best method, the Bristow or Latarjet procedure.

PURPOSE

To analyze the results of coracoid process transfer for the treatment of recurrent glenohumeral dislocations and to compare the results of this transfer between the Bristow and Latarjet techniques.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

The databases surveyed for this review included J-STAGE; Cochrane Bone, Joint and Muscle Trauma Group Specialized Register; Cochrane Controlled Register of Trials; MEDLINE; Ovid; Embase; Google Scholar; and CINAHL. Inclusion criteria consisted of (1) studies related to anterior glenohumeral dislocations treated with transfer of the coracoid process to the anterior glenoid rim and (2) studies that could provide data to perform at least 1 meta-analysis or other statistical evaluation. Titles and abstracts were reviewed for inclusion; thereafter, outcomes and the risk of bias were extracted. Statistical analyses were performed according to the nature of the data. When possible, the 95% CI was included.

RESULTS

Of the 779 studies found, 63 were able to provide data assessing 3395 shoulders. There were no randomized, blinded, or double-blinded trials. The recurrence of dislocations was assessed in 41 studies that used the Bristow technique (n = 2346 shoulders; percentage redislocations [mean ± SE], 1.00% ± 0.20%) and 18 studies that used the Latarjet technique (n = 930 shoulders; percentage redislocations, 2.13% ± 0.49%) (P = .04). The mean loss of external rotation was 12.91° for the Bristow procedure (n = 1440 shoulders) and 11.70° for the Latarjet procedure (n = 243 shoulders). The mean quality-of-life outcome scores were as follows for the Bristow and Latarjet procedures, respectively: Rowe score, 92.06 and 89.33; Western Ontario Shoulder Instability Index score, 16.44% and 19.68%; Japanese Orthopaedic Association score, 93.28 and 92.00; and American Shoulder and Elbow Surgeons score, 91.00 and 89.90.

CONCLUSION

Transferring the coracoid to the anteroinferior border of the glenoid through the subscapularis tendon is effective, regardless of the technique. When comparing the Bristow and Latarjet techniques, the recurrence of dislocations was the only outcome that could undergo a meta-analysis, and it presented a statistically significant difference in favor of the Bristow procedure. All other outcomes presented no clinically significant differences between their effect sizes. More studies presenting better methodology are still needed to achieve more robust conclusions.

Monocortical fixation of the coracoid in the Latarjet procedure is significantly weaker than bicortical fixation

PURPOSE

A crucial step of the Latarjet procedure is the fixation of the coracoid process onto the glenoid. Multiple problems associated with the fixation have been described, including lesions of the suprascapular nerve due to prominence of the screw or bicortical drilling. The purpose of the present study was to evaluate whether monocortical fixation, without perforating the posterior glenoid cortex, would provide sufficient graft stability.

METHODS

Coracoid transfer was performed in 14 scapula models (Sawbones^®, Composite Scapula, 4th generation). Two groups were assigned: in one group, fixation was achieved with two screws that did not perforate the posterior cortex of the glenoid neck (monocortical fixation), in the other group, fixation was achieved with perforation of the posterior cortex (bicortical fixation). The ultimate failure load and mode of failure were evaluated biomechanically.

RESULTS

Monocortical fixation was a significantly weaker construct than bicortical fixation (median failure load 221 N, interquartile range 211-297 vs. median failure load 423 N, interquartile range 273-497; p = 0.017). Failure was either due to a pullout of the screws from the socket or a fracture of the glenoid. There was no significant difference in the mode of failure between the two groups (n.s.).

CONCLUSION

Monocortical fixation was significantly weaker than bicortical fixation. However, bicortical drilling and overly long screws may jeopardize the suprascapular nerve. Thus, anatomic knowledge about the safe zone at the posterior rim of the glenoid is crucial. Until further research has evaluated, if the inferior stability is clinically relevant, clinicians should be cautious to use a monocortical fixation technique for the coracoid graft.

Clinical Outcomes and Recurrence Rates After Arthroscopic Stabilization Procedures in Young Patients With a Glenoid Bone Erosion: A Comparative Study Between Glenoid Erosion More and Less Than 20

PURPOSE

To evaluate the clinical outcomes and recurrence rates of arthroscopic stabilization procedures in young patients who had recurrent anterior shoulder instability with a glenoid bone erosion more than 20%, and to compare with those in patients with a glenoid bone erosion less than 20%.

METHODS

A total of 161 patients who underwent an arthroscopic stabilization procedure for recurrent anterior shoulder instability with anterior glenoid bone erosions and at least 2 years of follow-up were included. Patients were divided into 2 groups based on the glenoid defect size (group I [32 patients]: erosion >20%, group II [129 patients]: erosion <20%). The clinical outcomes were compared using the American Shoulder Elbow Surgeons (ASES) score, Rowe score, and sports/recreation activity level between the 2 groups. Postoperative complications including instability recurrence were documented.

RESULTS

The mean glenoid defect size was 22.1 ± 2.1% in group I, and 12.2 ± 3.7% in group II. In group I, clinical outcomes were significantly improved after operation (ASES score: 57.9 ± 14.3 at initial, 88.9 ± 6.2 at the last visit, P = .001; Rowe score: 42.1 ± 15.6 at initial, 87.4 ± 7.6 at the last visit, P = .001). These results were inferior to the clinical outcomes of patients in group II (ASES score: 91.5 ± 12.7, P < .001; Rowe score: 89.3 ± 12.4, P = .01). Postoperative recurrences occurred in 5 patients (15.6%) in group I, whereas patients in group II showed 5.4% of recurrence rate (P = .05). Competent recoveries to sports/recreation activity were achieved in 84.4% of patients in group I.

CONCLUSIONS

Arthroscopic stabilization procedures for recurrent anterior shoulder instability in young patients with glenoid bone erosions more than 20% showed satisfactory clinical outcomes and recurrence rate, although these results were inferior to those of patients with glenoid erosions less than 20%. Arthroscopic stabilization procedures can be applied as the primary treatment of recurrent anterior shoulder instability with a large glenoid bone erosion for functional restoration and return to previous sports activity level.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Allograft Use in Shoulder Surgery: Instability and Rotator Cuff

Shoulder instability and rotator cuff pathology can provide a challenging problem, especially in the revision setting. Allograft use in primary or revision surgical intervention for shoulder instability and rotator cuff tear may be a valuable resource. This paper reviews allograft tissue use in shoulder surgery for instability and rotator cuff tear.

The Eden-Hybbinette procedure is one hundred years old! A historical view of the concept and its evolutions

INTRODUCTION

One hundred years ago, before Bankart, Latarjet or Bristow, Eden and Hybbinette developed a procedure to treat anterior shoulder instability and currently, this eponymous term is known by every shoulder surgeon. The purpose of this review is to summarise the historical "Eden-Hybbinette" procedure and its evolutions during the last century and discuss results.

METHOD

On the centenary of the first publication on the "Eden-Hybbinette procedure", a search was conducted on Medline, Google Scholar and in the grey literature, to find its initial concept and description, and the evolutions.

RESULTS

The initial procedure was based on the concepts of glenoid bony augmentation (anatomic reconstruction with an autograft from the tibia) and capsulorrhaphy. The main evolutionary themes identified were the origin of the graft (autograft with iliac crest, allograft), graft positioning and fixation (no fixation device, screws), and the surgical approach (split of the subscapularis tendon in open surgery, arthroscopy). Studies with long-term follow-up exhibited good results, considered similar as those with other classic bone-block procedures. Development of osteoarthritis during the following years after the procedure is not usual and not related to the graft unless if there is articular protrusion.

CONCLUSION

The Eden-Hybbinette procedure is one of the oldest surgical interventions still commonly used for chronic anterior shoulder instability. The changes to the procedure over the last 100 years allow it to remain a contemporary solution for both primary surgery and revision cases.

Atypical traumatic anterior shoulder instability with excessive joint laxity: recurrent shoulder subluxation without a history of dislocation

BACKGROUND

No previously published studies have examined recurrent traumatic incomplete events in patients with excessive joint laxity. The purpose of this study is to investigate outcomes after arthroscopic stabilization for recurrent traumatic shoulder subluxation in patients with excessive joint laxity but no history of dislocation.

METHODS

This study included 23 patients with glenoid bone defects less than 20% who underwent arthroscopic stabilization of recurrent shoulder subluxation and were available for at least 2 years follow-up. Outcomes were assessed with the subjective shoulder value (SSV), University of California Los Angeles (UCLA) shoulder score, Rowe score, and sports/recreation activity level.

RESULTS

Postoperatively, overall functional scores improved significantly (p <  0.001), compared to preoperative scores: SSV improved from 49.1 to 90.4; Rowe score improved from 36.7 to 90.2; and UCLA shoulder score improved from 26.3 to 32.5. Patient satisfaction rate was 87% (20/23 patients). Sports/recreation activity level (return to premorbid activity level; grade I = 100% to grade IV = less than 70%) was grade I in 7 patients, grade II in 11, grade III in 3, grade IV in 2. The incidence of any glenoid bone defect was 61% (14/23 patients), and the mean glenoid bone defect size was 8%; among these 14 patients, 8 (35%) exhibited 15-20% glenoid bone defects. Instability reoccurred in 2 patients (9%) who had 15-20% glenoid bone defect.

CONCLUSION

Despite excessive joint laxity, overall functional outcomes after arthroscopic stabilization of recurrent shoulder subluxation were satisfactory. However, arthroscopic Bankart repair may not be reliable in patients with excessive joint laxity plus a glenoid bone defect size of more than approximately 15%.

Glenoid Bone Loss in Posterior Shoulder Instability: Prevalence and Outcomes in Arthroscopic Treatment

BACKGROUND

Glenoid bone loss is a well-accepted risk factor for failure after arthroscopic stabilization of anterior glenohumeral instability. Glenoid bone loss in posterior instability has been noted relative to its existence in posterior instability surgery. Its effect on outcomes after arthroscopic stabilization has not been specifically evaluated and reported.

PURPOSE

The purpose was to evaluate the presence of posterior glenoid bone loss in a series of patients who had undergone arthroscopic isolated stabilization of the posterior labrum. Bone loss was then correlated to return-to-duty rates, complications, and validated patient-reported outcomes.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

A retrospective review was conducted at a single military treatment facility over a 4-year period (2010-2013). Patients with primary posterior instability who underwent arthroscopic isolated posterior labral repair were included. Preoperative magnetic resonance imaging was used to calculate posterior glenoid bone loss using a standardized "perfect circle" technique. Demographics, return to duty, complications, and reoperations, as well as outcomes scores including the Single Assessment Numeric Evaluation and the Western Ontario Shoulder Instability Index (WOSI) scores, were obtained. Outcomes were analyzed across all patients based on percentage of posterior glenoid bone loss. Bone loss was then categorized as below or above the subcritical threshold of 13.5% to determine if bone loss effected outcomes similar to what has been shown in anterior instability.

RESULTS

There were 43 consecutive patients with primary, isolated posterior instability, and 32 (74.4%) completed WOSI scoring. Mean follow-up was 53.7 months (range, 25-82 months) The mean posterior glenoid bone loss was 7.3% (0%-21.5%). Ten of 32 patients (31%) had no appreciable bone loss. Bone loss exceeded 13.5% in 7 of 32 patients (22%), and 2 patients (6%) exceeded 20% bone loss. Return to full duty or activity was nearly 90% overall. However, those with >13.5%, subcritical glenoid bone loss, were statistically less likely to return to full duty (relative risk = 1.8), but outcomes scores, complications, and revision rates were otherwise not different in those with no or minimal bone loss versus those with more significant amounts.

CONCLUSION

Posterior glenoid bone loss has not previously been evaluated independently relative to patients with shoulder instability repairs. Sixty-nine percent of our patients had measurable bone loss, and 22% had greater than 13.5%, or above subcritical bone loss. While these patients were statistically less likely to return to full duty, the reoperation rate, complications, and patient-reported outcomes between groups were not different.

Accuracy and Reliability of a Simple Calculation for Measuring Glenoid Bone Loss on 3-Dimensional Computed Tomography Scans

PURPOSE

To establish the accuracy and reliability of the circle-line method (CLM) of measuring glenoid bone loss; to compare the CLM calculation with a traditionally used method of calculating a ratio; and to evaluate surgeons' ability to estimate the amount of glenoid bone loss before performing any calculations.

METHODS

Three-dimensional reconstructions of computed tomography scans of consecutive patients with anterior instability and glenoid bone loss were reviewed by 13 surgeons blinded to the diagnosis. The reviewers made estimations of bone loss before creating any measurements by viewing the available computed tomography scan as well as the 3-dimensional reconstructions. They selected an en face view of the glenoid to create a best-fit circle. Bone loss calculation with a traditional linear method as well as a CLM calculated by algebraic geometry was completed. The CLM requires calculation of the diameter of a best-fit circle on the glenoid, as well as the length of a single line along the circle representing the line of bone loss. All methods were compared with a computerized method of tracing the area of the glenoid within a best-fit circle. Interobserver and intraobserver calculations were performed. Analysis-of-variance testing was used to compare the estimates of bone loss versus the CLM-calculated bone loss. Tukey post hoc analysis was used to define the accuracy of the CLM calculation compared with a more traditional method of calculating bone loss.

RESULTS

Bone loss estimations were significantly different from CLM-calculated bone loss in all cases except those with greater than 25% bone loss. The CLM was more accurate in all types of bone loss except cases of greater than 25% bone loss. Interobserver reliability was very good for the glenoid diameter measurement and moderate for the CLM. Intraobserver reliability ranged from moderate to good for all methods of measurement.

CONCLUSIONS

Surgeon estimations of glenoid bone loss, as well as traditional line-measurement calculations, are inconsistent and unreliable for accurate determination of the optimal surgical treatment for anterior shoulder instability. The CLM is a simple, reproducible, and accurate method for determining glenoid bone loss and does not require specialized software or imaging protocols.

LEVEL OF EVIDENCE

Level II, diagnostic study.

Influence of screw type and length on fixation of anterior glenoid bone grafts

BACKGROUND

Bone-grafting procedures for recurrent shoulder instability produce low recurrence rates, although they are associated with complications such as graft non-union. Inadequate screw purchase is considered to play a causative role. However, excessive screw length can endanger neurovascular structures. The present study aimed to investigate how type and length of screws influences construct rigidity in a simplified glenoid model.

METHODS

Testing was performed on composite polyurethane foam models with material properties and abstract dimensions of a deficient glenoid and an bone graft. Three screw types (cannulated 3.75 mm and 3.5 mm and solid 4.5 mm) secured the graft in a bicortical-bicortical, bicortical-unicortical and unicortical-unicortical configuration. Biomechanical testing consisted of applying axial loads when measuring graft displacement.

RESULTS

At 200 N, graft displacement reached 0.74 mm, 0.27 mm and 0.24 mm for the unicortical-unicortical and 0.40 mm, 0.25 mm and 0.24 mm for the unicortical-bicortical configuration of the 3.75 mm, 3.5 mm and 4.5 mm screw types. The 3.75 mm screw incurred significant displacements in the unicortical configurations compared to the bicortical-bicortical method (p < 0.001).

CONCLUSIONS

The present study demonstrates that common screw types resist physiological shear loads in a bicortical configuration. However, the 3.75 mm screws incurred significant displacements at 200 N in the unicortical configurations. These findings have implications regarding hardware selection for bone-grafting procedures.

Open shoulder stabilization: current trends and 1-year postoperative complications

Background

Shoulder instability is commonly treated by arthroscopic stabilization. However, open stabilization procedures remain important in management of complex instability. Despite continued use of these procedures, the relative frequency of related complications remains poorly described. This study investigates current trends in open shoulder stabilization and characterizes major postoperative complications.

Methods

PearlDiver, a national insurance database of orthopedic patients, was used to identify open shoulder stabilization procedures from 2007 to 2010. Current Procedural Terminology codes for 4 procedures—Bankart repair, coracoid transfer, and anterior and posterior glenoid bone grafting—were used to track procedural trends. The 1-year postoperative complications were identified and categorized into 5 groups: dislocation treated with closed reduction, closed manipulation under anesthesia, reoperation with arthroscopy, reoperation with open surgery, and others. χ² analysis determined statistical significance.

Results

There were 2678 open shoulder stabilization procedures performed, with a 1-year complication rate of 12.3%. Relative proportion of open Bankart repairs decreased (82.5% to 69.8%), whereas proportion of coracoid transfers increased (7.7% to 19%). Posterior glenoid bone grafting had the highest complication rate (20.7%). Rate of total complications was 9.8% in patients 10-24 years, 13.6% in patients 25-54 years, and 25.9% in patients >55 years.

Conclusions

Based on our patient database sample, a significant decline in the relative use of open Bankart repair was observed. Our analysis indicates that the use of bone transfer procedures was correlated with significantly higher reoperation rates than open Bankart repair, particularly in the older patient cohort. Further studies comparing open stabilization procedures with contemporary arthroscopic techniques are indicated.

The Effect of Subcritical Bone Loss and Exposure on Recurrent Instability After Arthroscopic Bankart Repair in Intercollegiate American Football

BACKGROUND

There is no consensus on the optimal method of stabilization (arthroscopic or open) in collision athletes with anterior shoulder instability.

PURPOSE

To examine the effect of "subcritical" bone loss and football-specific exposure on the rate of recurrent shoulder instability after arthroscopic stabilization in an intercollegiate American football population.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Fifty intercollegiate football players underwent primary arthroscopic stabilization for anterior shoulder instability and returned to football for at least a single season. Preoperatively, 32 patients experienced recurrent subluxations, and 18 patients experienced a single or recurrent dislocation. Shoulders with glenoid bone loss >20%, an engaging Hill-Sachs lesion, an off-track lesion, and concomitant rotator cuff repair were excluded from the study. The primary outcome of interest was the ability to return to football without subsequent instability. Patients were followed for time to a subsequent instability event after return to play using days of exposure to football and total follow-up time after arthroscopic stabilization.

RESULTS

Fifty consecutive patients returned to American football for a mean 1.5 seasons (range, 1-3) after arthroscopic stabilization. Three of 50 (6%; 95% CI, 1.3%-16.5%) patients experienced recurrent instability. There were no subsequent instability events after a mean 3.2 years of military service. All shoulders with glenoid bone loss >13.5% (n = 3) that underwent arthroscopic stabilization experienced recurrent instability upon returning to sport, while none of the shoulders with <13.5% glenoid bone loss (n = 47) sustained a recurrent instability event during football ( X² = 15.80, P < .001). Shoulders with >13.5% glenoid bone loss had an incidence rate of 5.31 cases of recurrent instability per 1000 athlete-exposures of football. In 72,000 athlete-exposures to football with <13.5% glenoid bone loss, there was no recurrent instability. Significantly more anchors were used during the primary arthroscopic stabilization procedure in patients who experienced multiple preoperative instability events ( P = .005), and lesions spanned significantly more extensive portions along the circumference of the glenoid ( P = .001) compared with shoulders having a single preoperative instability event before surgical stabilization.

CONCLUSION

Arthroscopic stabilization of anterior shoulder instability in American football players with <13.5% glenoid bone loss provides reliable outcomes and low recurrence rates.

Computerized tomographic assessment and clinical evaluation in shoulder instability treated with the Latarjet-Patte procedure using one screw and washer

BACKGROUND

The Latarjet-Patte (L-P) procedure is indicated in anterior instability of the shoulder with a glenoid or humeral bone loss. Our purpose is to evaluate clinical outcome and computerized tomographic (CT) findings as position and resorption of the graft and articular degeneration.

METHODS

From 2006 to 2009 50 patients underwent to L-P, 48 was contacted by telephone and 26 were available for follow-up (3 to 6 years). Quick-DASH and Rowe scores was used, 22 patients perform CT.

RESULTS

None of contacted patients reported a new dislocation. The clinical outcome in the 26 followed patients was excellent: mean Quick DASH score: 1.9; mean ROWE score was 94.7. CT scans showed no evidence of articular degeneration of humeral head. There was partial resorption of the graft in 13 patients. We found a correlation between the zone of partial resorption and position of the graft.

CONCLUSIONS

CT scan is appropriate to study position and the healing of coracoid graft. A correct choice of where to place the graft together with a wide bone contact and stable synthesis does not cause degenerative changes after 6 years in our series.

LEVEL OF THE EVIDENCE

IV.

Arthroscopic Bankart repair associated with subscapularis augmentation (ASA) versus open Latarjet to treat recurrent anterior shoulder instability with moderate glenoid bone loss: clinical comparison of two series

PURPOSE

The treatment of chronic anterior shoulder instability with glenoid bone loss is still debated. The purpose of this study is to compare short-term results of two techniques treating chronic shoulder instability with moderate glenoid bone loss: bone block according to open Latarjet-Patte procedure and arthroscopic Bankart repair in association with subscapularis augmentation.

METHODS

Ninety-one patients with moderate anterior glenoid bone loss underwent from 2011 to 2015. From these patients, two groups of 20 individuals each have been selected. The groups were homogeneous in terms of age, gender, dominance and glenoid bone loss. In group A, an open Latarjet procedure has been performed, and in group B, an arthroscopic Bankart repair associated with subscapularis augmentation has been performed. The mean follow-up in group A was 21 months (20-39 months), while in group B was 20 months (15-36 months). QuickDash score, Constant and Rowe shoulder scores, were used for evaluations of results.

RESULTS

The mean preoperative rate of QuickDash score was 3.6 for group A and 4.0 for group B; Rowe Score was 50.0 for group A and 50.0 for group B. Preoperative mean Constant score was 56.2 for Latarjet-Patte and 55.2 for Bankart plus ASA. Postoperative mean QuickDash score was in group A 1.8 and 1.7 in group B; Rowe Score was 89.8 and 91.6; Constant Score was 93.3 and 93.8. No complications related to surgery have been observed for both procedures. Not statistically significant difference was reported between the two groups (p > .05). Postoperatively, the mean deficit of external rotation in ER1 was -9° in group A and -8 in group B; In ER2, the mean deficit was -5° in both groups (p = .0942).

CONCLUSIONS

Arthroscopic subscapularis augmentation of Bankart repair is an effective procedure for the treatment of recurrent anterior shoulder instability with glenoid bone loss without any significant difference in comparison with the well-known open Latarjet procedure.

3D-MR vs. 3D-CT of the shoulder in patients with glenohumeral instability

OBJECTIVE

To determine whether 3D-MR osseous reformats of the shoulder are equivalent to 3D-CT osseous reformats in patients with glenohumeral instability.

MATERIALS AND METHODS

Patients with glenohumeral instability, who were to be imaged with both CT and MRI, were prospectively selected. CT and MR were performed within 24 h of one another on 12 shoulders. Each MR study included an axial 3D isotropic VIBE sequence. The image data from the isotropic VIBE sequence were post-processed using subtraction and 3D software. CT data were post-processed using 3D software. The following measurements were obtained for both 3D-CT and 3D-MR post-processed images: height and width of the humeral head and glenoid, Hill-Sachs size and percent humeral head loss (if present), size of glenoid bone loss and percent glenoid bone loss (if present). Paired t-tests and two one-sided tests for equivalence were used to assess the differences between imaging modalities and equivalence.

RESULTS

The measurement differences from the 3D-CT and 3D-MR post-processed images were not statistically significant. The measurement differences for humeral height, glenoid height and glenoid width were borderline statistically significant; however, using any adjustment for multiple comparisons, this failed to be significant. Using an equivalence margin of 1 mm for measurements and 1.5% for percent bone loss, the 3D-MR and 3D-CT post-processed images were equivalent.

CONCLUSION

Three-dimensional-MR osseous models of the shoulder using a 3D isotropic VIBE sequence were equivalent to 3D-CT osseous models, and the differences between modalities were not statistically significant.

All-Arthroscopic Revision Eden-Hybinette Procedure for Failed Instability Surgery: Technique and Preliminary Results

PURPOSE

To describe the technique of an all-arthroscopic Eden-Hybinette procedure in the revision setting for treatment of a failed instability procedure, particularly after failed Latarjet, as well as to present preliminary results of this technique.

METHODS

Between 2007 and 2011, 18 shoulders with persistent instability after failed instability surgery were treated with an arthroscopic Eden-Hybinette technique using an autologous bicortical iliac crest bone graft. Of 18 patients, 12 (9 men, 3 women) were available for follow-up. The average follow-up was 28.8 months (range, 15 to 60 months). A Latarjet procedure was performed as an index surgery in 10 patients (83%). Two patients (17%) had a prior arthroscopic Bankart repair.

RESULTS

Eight patients (67%) obtained a good or excellent result, whereas 4 patients (33%) reported a fair or poor result. Seven patients (58%) returned to sport activities. A positive apprehension test persisted in 5 patients (42%), including 2 patients (17%) with recurrent subluxations. The Rowe score increased from 30.00 to 78.33 points (P < .0001). The Walch-Duplay score increased from 11.67 to 76.67 points (P < .0001). The Western Ontario Shoulder Instability Index score showed a good result of 28.71% (603 points). The average anterior flexion was 176° (range, 150° to 180°), and the average external rotation was 66° (range, 0° to 90°). Two patients (16.67%) showed a progression of glenohumeral osteoarthritic changes, with each patient increasing by one stage in the Samilson-Prieto classification. All 4 patients (33%) with a fair or poor result had a nonunion identified on postoperative computed tomography scan.

CONCLUSIONS

An all-arthroscopic Eden-Hybinette procedure in the revision setting for failed instability surgery, although technically demanding, is a safe, effective, and reproducible technique. Although the learning curve is considerable, this procedure offers all the advantages of arthroscopic surgery and allows reconstruction of glenoid defects and restoration of shoulder stability in this challenging patient population. In our hands, this procedure yields good or excellent results in 67% of patients. Successful outcome is correlated with bony healing of the iliac crest graft to the glenoid.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Coracoid bone block fixation with cortical buttons: An alternative to screw fixation?

BACKGROUND

The purpose of this study was to evaluate suture button fixation in a bone block (Bristow and Latarjet) procedure. We hypothesize that (1) cortical button fixation will allow predictable and reproducible bone union and (2) minimize the complications reported with screw fixation.

MATERIALS AND METHODS

Seventy patients (mean age, 27 years) underwent an arthroscopic bone block procedure with a guided surgical approach and suture button fixation for recurrent anterior shoulder instability. There were two groups of patients: 35 Bristow procedures (group A) and 35 Latarjet procedures (group B). Bone graft union and positioning accuracy were assessed by postoperative computed tomography imaging at 2 weeks and 6 months, respectively.

RESULTS

The coracoid graft was positioned below the equator in 93% and strictly tangential to the glenoid surface in 94% of the cases. Bone healing was observed in 83% of the cases (58/70) with 74% bone union in group A and 91% in group B. Neurologic and hardware complications, classically reported with screw fixation, were not observed with this novel fixation method.

CONCLUSIONS

(1) Suture button fixation can be an alternative to screw fixation, obtaining bone block union, (2) in the lying position (Latarjet) bone healing was better than in the standing position (Bristow), and (3) complications classically reported with screw fixation were not observed.

LEVEL OF EVIDENCE

Level IV.

Distal tibia allograft for glenohumeral instability: does radius of curvature match?

BACKGROUND

A distal tibia osteochondral allograft is a potential graft option for glenoid reconstruction because the distal tibia may have a similar radius of curvature (ROC) as the glenoid. This study evaluated ROC mismatch as measured on computed tomography (CT) scans between the glenoid, distal tibia, and humeral head.

METHODS

Bilateral CT images were formatted for 10 decedents from the Office of the Medical Investigator database, giving 20 specimens per anatomic location. The ROCs of the glenoid, distal tibia, and humeral head were measured. A statistical model was generated to assess ROC mismatch of randomly paired distal tibias and glenoids.

RESULTS

The mean ± standard deviation ROC was 2.9 ± 0.25 cm for the glenoid, 2.3 ± 0.21 cm for the distal tibia, and 2.5 ± 0.12 cm for the humeral head. No differences were found in laterality, intraobserver, or interobserver measurements. The least-squares difference in the ROC between the glenoid and tibia was 0.57 cm, glenoid and humerus was 0.40 cm, and humerus and tibia was 0.17 cm. Only 22% of randomly paired distal tibias and glenoids had a difference in ROC of 0.3 cm or less.

CONCLUSION

CT measurement of the ROC of the glenoid, distal tibia, and humeral head is reliable and reproducible. The probability of obtaining a random distal tibia allograft with a similar ROC to the glenoid is low. Obtaining ROC measurements of the injured glenoid and the distal tibia allograft specimen before use for glenoid reconstruction may be useful.

Coracoid Process: The Lighthouse of the Shoulder

The coracoid process is a hook-shaped bone structure projecting anterolaterally from the superior aspect of the scapular neck. Surgeons often refer to the coracoid process as the "lighthouse of the shoulder" given its proximity to major neurovascular structures such as the brachial plexus and the axillary artery and vein, its role in guiding surgical approaches, and its utility as a landmark for other important structures in the shoulder. The coracoid also serves as a critical anchor for many tendinous and ligamentous attachments. These include the tendons of the pectoralis minor, coracobrachialis, and short head of the biceps brachii muscles, and the coracoclavicular, coracohumeral, coracoacromial, and transverse scapular ligaments. Consequently, the coracoid and its associated structures are linked to numerous shoulder pathologic conditions. This article will detail the anatomy of the coracoid and its associated structures and review the clinical and radiologic findings of corresponding pathologic conditions in this region with original illustrations and multimodality imaging examples. Highlighted in this article are the coracoclavicular joint, the classification and management of coracoid fractures, subcoracoid impingement, the coracoacromial arch and subacromial impingement, the coracohumeral ligament and the biceps pulley, the coracoclavicular ligament and its surgical reconstruction, adhesive capsulitis, the suprascapular notch and suprascapular notch impingement, subcoracoid bursitis, coracoid transfer procedures, and coracoid tumors. A brief summary of the pathophysiology, potential causes, and management options for each of the pathologic entities will also be discussed. ^©RSNA, 2016.

Autologous distal clavicle versus autologous coracoid bone grafts for restoration of anterior-inferior glenoid bone loss: a biomechanical comparison

BACKGROUND

Treating anterior glenoid bone loss in patients with recurrent shoulder instability is challenging. Coracoid transfer techniques are associated with neurologic complications and neuroanatomic alterations. The purpose of our study was to compare the contact area and pressures of a distal clavicle autograft with a coracoid bone graft for the restoration of anterior glenoid bone loss. We hypothesized that a distal clavicle autograft would be as effective as a coracoid graft.

METHODS

In 13 fresh-frozen cadaveric shoulder specimens, we harvested the distal 1.0 cm of each clavicle and the coracoid bone resection required for a Latarjet procedure. A compressive load of 440 N was applied across the glenohumeral joint at 30° and 60° of abduction, as well as 60° of abduction with 90° of external rotation. Pressure-sensitive film was used to determine normal glenohumeral contact area and pressures. In each specimen, we created a vertical, 25% anterior bone defect, reconstructed with distal clavicle (articular surface and undersurface) and coracoid bone grafts, and determined the glenohumeral contact area and pressures. We used analysis of variance for group comparisons and a Tukey post hoc test for individual comparisons (with P <.05 indicating a significant difference).

RESULTS

The articular distal clavicle bone graft provided the lowest mean pressure in all testing positions. The coracoid bone graft provided the greatest contact area in all humeral positions, but the difference was not significant.

CONCLUSION

An articular distal clavicle bone graft is comparable in glenohumeral contact area and pressures to an optimally placed coracoid bone graft for restoring glenoid bone loss.

LEVEL OF EVIDENCE

Basic Science Study; Biomechanics.

A systematic review and meta-analysis of clinical and patient-reported outcomes following two procedures for recurrent traumatic anterior instability of the shoulder: Latarjet procedure vs. Bankart repair

BACKGROUND

The Bankart repair and Latarjet procedure are both viable surgical options for recurrent traumatic anterior instability of the shoulder joint. The anatomic repair is the more popular option, with 90% of surgeons internationally choosing the Bankart repair as the initial treatment. There has been no previous review directly comparing the 2 techniques. Hence, we aimed to systematically review studies to compare the outcomes of Bankart repairs vs. the Latarjet procedure for recurrent instability of the shoulder.

METHODS

Six electronic databases were searched for original, English-language studies comparing the Bankart and Latarjet procedures. Studies were critically appraised using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. Data were extracted from the text, tables, and figures of the selected studies.

RESULTS

Eight comparative studies were identified with 795 shoulders; 416 of them underwent open or arthroscopic Bankart repairs, and 379 were repaired by the open Latarjet procedure. Primary and revision procedures were studied. The Latarjet procedure conferred significantly lower risk of recurrence and redislocation. There was no significant difference in the rates of complication requiring reoperation between the two procedures. Rowe scores were higher and loss of external rotation lower in the Latarjet group compared with the Bankart repair group.

CONCLUSIONS

Our studies demonstrate that the Latarjet procedure is a viable and possibly superior alternative to the Bankart repair, offering greater stability with no significant increase in complication rate. However, the studies identified were retrospective and of limited quality, and therefore randomized controlled trials with large populations of patients or prospective assessment of national orthopedic registries should be employed to confirm our findings.

Predictors of functional outcomes and recurrent shoulder instability after arthroscopic anterior stabilization

PURPOSE

To investigate what factors might predict the results of arthroscopic stabilization for anterior shoulder instability.

METHODS

One hundred and forty-three patients averaging 25 (15-58) years with traumatic anterior shoulder instability who underwent arthroscopic stabilization were reviewed at a median follow-up of 81 (24-172) months. Sixty-two (56.4 %) individuals were involved in contact sport activities, and there were 40 (30 %) patients who had only one dislocation prior to having surgery. Rowe score was measured preoperatively and at follow-up.

RESULTS

Thirty-three (23.1 %) patients experienced recurrent instability 12 (1-120) months after surgery, and 15 of those underwent further surgery. There was a statistically significant lower risk of failure (p = 0.027) for patients who had a surgical procedure after only one episode of shoulder dislocation. Patients treated after the second or further episode of shoulder dislocation exhibited a mean odds ratio for failure of 3.8 (95 % confidence interval 1.2-11.6, p = 0.044) with regard to first-time dislocators. The Rowe score significantly improved from a preoperative value of 25 (5-55) to a postoperative value of 100 (40-100) (p < 0.001). A significantly higher postoperative Rowe score was found in patients older than 24 years of age at the operation (p = 0.011) and in patients with less than eight dislocations prior to surgery (p = 0.05).

CONCLUSIONS

These results suggest that better functional results following arthroscopic stabilization can be expected in patients over 24 years of age and in those with a fewer number of dislocations preoperatively. A lower rate of recurrence can be expected if the patient undergoes surgery after the first episode of dislocation.

LEVEL OF EVIDENCE

Prognostic study, Level II.