Remplissage of an Off-track Hill-Sachs Lesion Is Necessary to Restore Biomechanical Glenohumeral Joint Stability in a Bipolar Bone Loss Model

Biomechanical Analysis Reveals Shoulder Instability With Bipolar Bone Loss Is Best Treated With Dynamic Anterior Stabilization for On-Track Lesions and With Remplissage for Off-Track Lesions

PURPOSE

To compare the biomechanical effects of augmenting Bankart repair (BR) with either remplissage or dynamic anterior stabilization (DAS) in the treatment of anterior shoulder instability with on-track or off-track bipolar bone loss.

METHODS

Eight fresh-frozen cadaveric shoulders were tested at 60° of glenohumeral abduction in the intact, injury, and repair conditions. Injury conditions included 15% glenoid bone loss with an on-track or off-track Hill-Sachs lesion as previously recommended. Repair conditions included isolated BR, BR with remplissage, and BR with DAS (long head of biceps transfer). The glenohumeral stability was assessed by measuring the anterior translation under 0, 10, 20, 30, 40, 50 N load and maximum load without causing instability at mid-range (60°) and end-range (90°) external rotation (ER). Maximum range of motion (ROM) was measured by applying a 2.2-N·m torque in passive ER and internal rotation.

RESULTS

Isolated BR failed to restore native glenohumeral stability in both on-track and off-track bipolar bone loss models. Both remplissage and DAS significantly decreased the anterior instability in the bipolar bone loss models, showing better restoration than the isolated BR. In the on-track lesions, DAS successfully restored native glenohumeral stability and mobility, whereas remplissage significantly decreased anterior translation without load (-2.12 ± 1.07 mm at 90° ER, P = .003; -1.98 ± 1.23 mm at 60° ER, P = .015). In the off-track lesions, remplissage restored native glenohumeral stability but led to significant ROM limitation (-8.6° ± 2.3° for internal rotation, P < .001; -13.9° ± 6.2° for ER, P = .003), whereas DAS failed to restore native stability at 90° ER regarding the increased anterior translation under 50 N (4.10 ± 1.53 mm, P < .001) and decreased maximum load (-13.8 ± 9.2 N, P = .021).

CONCLUSIONS

At time-zero, both remplissage and DAS significantly reduced residual anterior instability compared with isolated BR in the bipolar bone loss models and restored the native glenohumeral stability under most translational loads. However, remplissage could decrease the anterior translation without load for on-track lesions and may restrict ROM for off-track lesions, whereas DAS failed to restore native stability under high translational loads for off-track lesions.

CLINICAL RELEVANCE

DAS could be recommended to treat on-track bipolar bone loss with less biomechanical adverse effects, whereas remplissage might be the preferred procedure to address off-track bipolar bone loss for better stability.

Lower Range of Recurrent Instability Rates Following Bankart Repair and Remplissage Compared to Isolated Bankart Repair in Patients With "Nonengaging/On-Track" Hill-Sachs Lesions and <20% Glenoid Bone Loss

PURPOSE

To compare recurrent instability and return-to-sport rates along with external rotation differences between on-track (nonengaging) Hill-Sachs lesion patients undergoing either an isolated Bankart repair (IBR) or a Bankart repair augmented with a remplissage procedure (B+R).

METHODS

A search was conducted using 3 databases (PubMed, EMBASE, CINAHL) in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Only clinical comparative (level of evidence I-III) studies were considered for inclusion. Quality assessment was performed using the Methodological Index for Non-Randomized Studies criteria.

RESULTS

Six level of evidence III studies, totaling 537 patients (202 B+R and 335 IBR) were included for analysis. All patients had <20% glenoid bone loss and a nonengaging, on-track Hill-Sachs lesion. At a median final follow-up of 34.7 months, recurrent dislocation rates ranged from 0% to 7.7% and 3.5% to 30% in the B+R and IBR groups, respectively. Moreover, subjective instability and revision surgery rates presented lower ranges in the B+R upon comparison with the IBR cohort (0%-32% vs 5%-71.4% and 0%-5% vs 0%-35%, respectively). Furthermore, return to preinjury level of sports ranged from 64% to 100% in the remplissage-augmented group and 50% to 90% in the IBR cohort. Postoperative external rotation at side varied from 50° to 63° in the B+R and 55° to 63° in the IBR arm. Additional subgroup analysis revealed recurrent dislocation rates in athletes and patients with near-track Hill-Sachs lesions undergoing remplissage augmentation to be 0% to 5% and 2% to 47% while ranging from 8.8% to 30% and 9% to 66% for IBR patients, respectively.

CONCLUSIONS

Upon qualitative analysis, ranges of recurrent instability measures, including recurrent dislocation rates, are higher in patients undergoing IBR in comparison to B+R. Activity level influences outcomes as athletes were found to have a higher range of recurrent dislocation rates in the IBR group. The addition of remplissage showed a higher range of return-to-sport rates with comparable postoperative external rotation between groups.

LEVEL OF EVIDENCE

Level III, systematic review of Level III studies.

Stabilizing Mechanisms in Patients Treated Using Hill-Sachs Remplissage With Bankart Repair in Abduction-External Rotation Position

BACKGROUND

Hill-Sachs lesion (HSL) remplissage with Bankart repair (RMBR) provides a minimally invasive solution for treating HSLs and glenoid bone defects of <25%. The infraspinatus tendon is inserted into the HSL during the remplissage process, causing the infraspinatus to shift medially, leading to an unknown effect on glenohumeral alignment during the resting abduction-external rotation (ABER) and muscle-active states.

PURPOSE/HYPOTHESIS

The purpose of this study was to evaluate the possible check-rein effect and muscle-active control in stabilizing the glenohumeral joint after RMBR in vivo. We hypothesized that the check-rein effect and active control would stabilize the glenohumeral joint in the ABER position in patients after RMBR.

STUDY DESIGN

Controlled laboratory study.

METHODS

We included 42 participants-22 patients in group A who met the inclusion criteria after RMBR and 20 healthy participants in group B without shoulder laxity. Three-dimensional magnetic resonance imaging was performed to analyze the alignment relationship of the glenohumeral joint with and without muscular activity. Ultrasonic shear wave elastography was used to evaluate the elastic properties of the anterior capsule covered with the anterior bands of the inferior glenohumeral ligament.

RESULTS

Patients who underwent RMBR demonstrated more posterior (-1.81 ± 1.19 mm vs -0.76 ± 1.25 mm; P = .008) and inferior (-1.05 ± 0.62 mm vs -0.45 ± 0.48 mm; P = .001) shifts of the humeral head rotation center and less anterior capsular elasticity (70.07 ± 22.60 kPa vs 84.01 ± 14.08 kPa; P = .023) than healthy participants in the resting ABER state. More posterior (-3.17 ± 0.84 mm vs -1.81 ± 1.19 mm; P < .001) and less-inferior (-0.34 ± 0.56 mm vs -1.05 ± 0.62 mm; P < .001) shifts of the humeral head rotation center and less anterior capsular elasticity (36.57 ± 13.89 kPa vs 70.07 ± 22.60 kPa; P < .001) were observed in the operative shoulder during muscle-active ABER than in resting ABER states.

CONCLUSION

The check-rein effect and muscle-active control act as stabilizing mechanisms in RMBR during the ABER position.

CLINICAL RELEVANCE

Stabilizing mechanisms in RMBR during the ABER position include the check-rein effect and muscle-active control.

Remplissage reduced sense of apprehension and increased the rate of return to sports at preinjury level of elite overhead athletes with on-track anterior shoulder instability

PURPOSE

The purpose of this study was to compare the results of arthroscopic isolated Bankart repair (B) with Bankart repair plus Remplissage (B + R) procedure in contact overhead athletes with on-track anterior shoulder instability.

METHODS

A total of 64 athletes playing basketball, volleyball and handball in elite professional level who underwent arthroscopic isolated Bankart repair (34 patients) or Bankart repair plus Remplissage procedure (30 patients) with the diagnosis of recurrent anterior shoulder instability between 2017 and 2020, were retrospectively reviewed. Radiologically all patients had on-track Hill-Sachs defects and minimal or subcritical glenoid bone loss (< 13.5%). Patients were evaluated using pre- and postoperative pVAS, SANE, ASES, ROWE, WOSI scores and postoperative active ROM assessment. Patients were also asked for the frequency of any subjective apprehension and satisfaction with the surgery in four grades.

RESULTS

The mean ages of the groups B and B + R were 26.8 and 26 years (SD = 3.22), respectively; the mean follow-up times were 37.8 and 36.2 months (SD = 11.19). Compared with the preoperative status, there was a statistically significant improvement of all 5 postoperative outcome scores in both groups (P < 0.001). However, significant difference between the improvement of the groups were only found for the SANE (B: 22.3 ± 4.1, B + R: 26.3 ± 4.3; P = 0.0004), ASES (B: 26.1 ± 2.6, B + R: 30.2 ± 3.6; P < 0.001) and ROWE (B: 42 ± 3.7, B + R: 47.7 ± 2.8; P < 0.001) scores in favor of the group B + R. The loss of internal and external rotation of the adducted arm in group B + R was found to be approximately 5 degrees compared to the group B (P < 0.001). More than 80% of group B + R showed no apprehension in sports activities and almost completely returned to pre-injury athletic level, depicting statistically significant improvement compared to group B athletes (P = 0.002 and 0.036, respectively). 3 patients developed re-dislocation after isolated Bankart repair, whereas no re-dislocation occurred in the B + R group.

CONCLUSION

Adding Remplissage procedure to the Bankart repair provided an advantage in terms of both return to sport at preinjury level and the frequency of apprehension sensation during sports activity.

LEVEL OF EVIDENCE

III.

Cadaveric Biomechanical Study of Partial Glenoid Arthroplasty Versus the Latarjet Procedure for Anterior Glenoid Bone Loss

BACKGROUND

For severe anterior glenoid bone loss due to recurrent shoulder instability, the Latarjet procedure offers a dynamic sling effect in addition to bone augmentation. Yet, it heavily alters the surrounding anatomy, while fixation and graft union issues are also common.

PURPOSE/HYPOTHESIS

The purpose of this study was to compare a novel printed 3-dimensional (3D) partial glenoid arthroplasty (PGA) implant with the classic Latarjet procedure. It was hypothesized that by replicating the original glenoid geometry and preserving soft tissue anatomy, PGA may better reproduce normal joint kinematics. In addition, the locking screw construct may offer stronger fixation.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 14 matched cadaveric shoulders were tested. The PGA implant was 3D printed in titanium based on preoperative computed tomography. The intact, 25% anterior glenoid bone loss, and postoperative states were tested in the scapular and coronal planes. The following parameters were measured: articular surface area and stepoff, rotational range of motion and the humeral head apex position during rotation, and load and linear stiffness at 25% anterior translation and at 2-mm construct displacement.

RESULTS

The baseline dimensions of the glenoid articular surface were comparable between the groups. The articular surface area after PGA was significantly larger (P = .006) with less articular stepoff (P = .030). PGA better approximated the intact state's external (P = .006) and total (P = .019) rotational range of motion in the scapular plane. The course of the humeral head apex after PGA better followed that of the intact state (P < .001). Resistance against anterior translation after PGA was not significantly different compared with after the Latarjet procedure. Greater linear stiffness (P = .031) and loading (P = .002) at 2-mm construct displacement were demonstrated in the PGA group.

CONCLUSION

In addressing anterior glenoid bone loss, PGA better approximated intact glenohumeral joint kinematics compared with the Latarjet procedure with less articular stepoff in a cadaveric model. PGA was comparable in resisting anterior translation while being significantly stronger against loading at 2-mm construct displacement. Further clinical studies are warranted to validate this novel procedure.

CLINICAL RELEVANCE

A 3D-printed PGA implant may offer an alternative treatment option for severe glenoid bone loss due to shoulder instability, overcoming the previous drawbacks of the Latarjet procedure, including altered kinematics, fixation failure, and hardware issues.

The Triple-Double Technique of Arthroscopic Hill-Sachs Remplissage

Surgeons are increasingly treating Hill-Sachs lesions arthroscopically by suturing the posterior rotator cuff and capsule into the defect, a procedure known as "remplissage." A number of remplissage techniques have been described in the literature, and these often vary by the number and location of suture anchors. The "triple-double" technique of arthroscopic Hill-Sachs remplissage can be used for larger lesions. This technique utilizes a three-anchor configuration secured by interconnected double-mattress sutures to provide durable fixation through a large contact area between the capsulotenodesis tissue and the prepared bone bed to theoretically optimize healing.

Management of off-track Hill-Sachs lesions in anterior glenohumeral instability

Bone loss has been identified as a risk factor for recurrent shoulder dislocations or failure after soft tissue repair. Although the range for "critical" bone loss is yet to be determined, glenoid and humeral bone defects should not be regarded as independent problems, but the interaction between them during shoulder motion should be evaluated as suggested by the glenoid track concept. The glenoid track concept is now widely accepted and considered essential for making decisions about surgery. Soft-tissue procedures usually work well in patients with on-track Hill-Sachs lesions but in off-track lesions do not. In this situation additional procedures should be performed.Different surgical options have been described to address off-track Hill-Sachs lesions, most commonly remplissage, Latarjet or free bone block procedures. Coracoid graft and free bone grafts convert the off-track Hill-Sachs lesion into on-track by lengthening the glenoid-track, whereas remplissage fill-in the humeral lesion so that it does not engage. In the setting of a Hill-Sachs lesion with little or no glenoid bone loss, remplissage has demonstrated satisfactory outcomes with a low complications and recurrence rate. Favorable results have been reported with glenoid bone grafting when managing isolated Hill-Sachs or bipolar lesions. Studies analyzing Latarjet and Eden-Hybinette procedures show that both procedures are safe and effective in the management of anterior glenohumeral instability. Attention should be paid to those patients with large bone defects not amenable to be restored with an isolated Latarjet that may be better addressed with an Eden-Hybinnete or adding a remplissage to the Latarjet procedure.

Arthroscopic Bankart Repair With Remplissage as an Alternative to Latarjet for Anterior Glenohumeral Instability With More Than 15% Glenoid Bone Loss

BACKGROUND

Surgical management of anterior shoulder instability continues to evolve. The clinical effectiveness of arthroscopic Bankart repair with remplissage (REMP) in patients with increasing glenoid bone loss (GBL) has not been thoroughly compared with Latarjet.

PURPOSE/HYPOTHESIS

The purpose of this study was to compare 2-year outcomes of REMP versus open Latarjet in patients with >15% GBL. We hypothesized that there would be no difference.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A multicenter, retrospective study was performed on a consecutive series of patients who underwent primary REMP or Latarjet by 4 shoulder specialists between August 2013 and December 2019 for >15% GBL. Procedure performance was based on shared decision making between the surgeon and patient. Baseline and 2-year postoperative range of motion (ROM) and the following patient-reported outcomes (PROs) were collected: Western Ontario Shoulder Instability Index, Single Assessment Numeric Evaluation, and visual analog scale for pain. Return to sport, satisfaction, complications, recurrence, and revisions were reviewed.

RESULTS

A total of 47 patients were available for study, including 22 who underwent REMP and 25 who underwent Latarjet. Baseline demographic characteristics, ROM, and PROs were similar between the groups. Mean preoperative GBL (REMP 25.8% ± 7.8% vs Latarjet 25.1% ± 9.0%; P = .800) and off-track lesions (REMP 59.1% vs Latarjet 44.0%; P = .302) were similar. Postoperative change in external rotation favored Latarjet (10° ± 22° vs -4° ± 13°; P = .017). Postoperative PROs, return to the sports (86.4% vs 87.5%; P = .99), and satisfaction (95.5% vs 95.8%; P = .99) were similar between groups. There were no recurrent dislocations in either group. One infected hematoma was encountered in the Latarjet cohort.

CONCLUSION

At short-term follow-up, the hypothesis was upheld. REMP and Latarjet provided similar outcomes for patients with >15% GBL, although REMP patients experienced slightly decreased external rotation. Although larger series and longer-term follow-ups are required, remplissage may be considered in patients with >15% glenoid bone loss.

Arthroscopic Remplissage for the Treatment of Anterior Shoulder Instability: Current and Evolving Concepts

➢

A Hill-Sachs lesion (HSL) is a compression fracture on the posterolateral humeral head that can increase the risk of recurrent shoulder instability after isolated arthroscopic Bankart repair.

➢

Remplissage involves capsulotenodesis of the infraspinatus tendon and posterior capsule into the HSL to prevent its engagement with the glenoid rim through extra-articular conversion and restraint against humeral head anterior translation.

➢

The glenoid track concept can be applied preoperatively and intraoperatively to evaluate risk of recurrence and help direct clinical management options for recurrent shoulder instability.

➢

Recent literature supports expanding indications for remplissage to include patients with on-track HSLs who are at increased risk of recurrence including collision athletes, military personal, and patients with joint hyperlaxity.

➢

New techniques and suture constructs have demonstrated improved biomechanical strength while avoiding the need to access the subacromial space.

Comparison of computed tomography and 3D magnetic resonance imaging in evaluating glenohumeral instability bone loss

BACKGROUND

To determine whether the addition of 3-dimensional (3D) magnetic resonance imaging (MRI) to standard MRI sequences is comparable to 3D computed tomographic (CT) scan evaluation of glenoid and humeral bone loss in glenohumeral instability.

METHODS

Eighteen patients who presented with glenohumeral instability were prospectively enrolled and received both MRI and CT within 1 week of each other. The MRI included an additional sequence (volumetric interpolated breath-hold examination [VIBE]) that underwent postprocessing for reformations. The addition of a VIBE protocol, on average, is an additional 4-4.5 minutes in the scanner. CT data also underwent 3D postprocessing, and therefore each patient had 4 imaging modalities (2D CT, 2D MRI, 3D CT reformats, and 3D MRI reformats). Each sequence underwent the following measurements from 2 separate reviewers: glenoid defect, glenoid defect percentage, humeral defect, humeral defect percentage, and evaluation of glenoid track and version. Paired t tests were used to assess differences between imaging modalities and χ² for glenoid track. Intra- and interobserver reliability were evaluated. Bland-Altman tests were also performed to assess the agreement between CT and MRI. In addition, we determined the cost of each imaging modality at our institution.

RESULTS

3D MRI measurements for glenoid and humeral bone loss measurements were comparable to 3D CT (Table 1). There were no significant differences for glenoid defect size and percentage, or humeral defect size and percentage (P > .05) (Table 2). Bland-Altman analysis demonstrated strong agreement, with small measurement errors for 3D CT and 3D MRI percentage glenoid bone loss. There was also no difference in evaluation for determining on vs. off track between any of the imaging modalities. Inter- and intrarater reliability was good to excellent for all CT and MRI measurements (r ≥ 0.7).

CONCLUSION

3D MRI measurements for bone loss in glenohumeral instability through use of VIBE sequence were equivalent to 3D CT. At our institution, undergoing MRI with 3D reconstruction was 1.67 times cheaper than MRI and CT with 3D reconstructions. 3D MRI may be a useful adjuvant to standard MRI sequences to allow concurrent soft tissue and accurate assessment of glenoid and humeral bone loss in glenohumeral instability.

The Addition of Remplissage to Free Bone Block Restores Translation and Stiffness Compared to Bone Block Alone or Latarjet in a Bipolar Bone Loss Model

PURPOSE

The purpose of this study was to compare glenohumeral stability following a Latarjet, a free bone block (FBB), and a FBB with remplissage for bipolar bone loss.

METHODS

Nine matched pairs of fresh frozen cadavers were tested in a custom biomechanical apparatus with rotation and progressive translational loading. The free bone block group consisted of a distal tibial allograft with an all-suture tape construct. The Latarjet group was performed with the native coracoid and two partially threaded cannulated screws. A bipolar bone loss model was created with 20% glenoid bone loss and an off-track Hill-Sachs lesion. Testing conditions included the 1) native state, 2) bipolar bone loss model, 3) Latarjet, 4) FBB with distal tibial allograft secured with cerclage sutures, and 5) FBB with remplissage. Each condition was tested for translation, humeral head apex shift, stiffness, and dislocation force.

RESULTS

There were no differences in translation, stiffness, or dislocation forced between the FBB alone and Latarjet groups. The FBB with remplissage group demonstrated the lowest anterior-inferior translation at 90° of ER, which was statistically significant compared to Latarjet 20N (P = .013) and compared to the FBB alone at 40N (P = .024) and 50N (P = .011). The FBB with remplissage group was significantly stiffer compared to FBB alone at 90° ER with approximately 60% change in stiffness (P = .028). The force required to dislocate the humeral head after treatment was highest in the FBB with remplissage group, which was statistically significant compared to the FBB alone (P = .003) and Latarjet groups (P = .018).

CONCLUSION

The addition of remplissage to a FBB restores translation and stiffness closer to the intact state compared to a FBB alone or Latarjet in a bipolar bone loss model with an off-track Hill-Sachs lesion. In this model, dislocation force significantly increased with the addition of remplissage to the FBB.

CLINICAL RELEVANCE

This biomechanical study provides evidence that Latarjet and FBB are both acceptable forms of treatment for bipolar bone loss, but stability can be enhanced with the addition of remplissage following glenoid reconstruction.

Consideration May Be Given to Lowering the Threshold for the Addition of Remplissage in Patients With Subcritical Glenoid Bone Loss Undergoing Arthroscopic Bankart Repair

Purpose

Treatment for patients with anterior glenohumeral instability with subcritical bone loss is evolving. The purpose of this study was to compare 2-year outcomes of arthroscopic Bankart repair with and without Hill–Sachs remplissage in patients with <15% glenoid bone loss.

Methods

A multicenter retrospective study was performed on a consecutive series of patients who underwent primary isolated arthroscopic Bankart repair (IBR) or arthroscopic Bankart repair with remplissage (REMP) by 4 shoulder specialists between 2013 and 2019. Range of motion (ROM) and patient-reported outcomes (PROs) were collected at baseline and 2 years postoperative: Western Ontario Shoulder Instability Index, Single Assessment Numeric Evaluation, and visual analog scale for pain. Recurrence, return to sport, satisfaction, complications, and revisions also were reviewed.

Results

A total of 123 patients were available, including 75 IBR and 48 REMP. Baseline demographics, activity, ROM, and PROs were similar. Mean glenoid bone loss (2.5% vs 6.1%: P < .001) was greater in REMP, although the number of on-track lesions was similar (98.7% vs 93.8%: P = .298). WOSI scores were improved for REMP (196.5 vs 42.7: P = .004), but otherwise no difference in postoperative PROs or ROM. Differences between cohorts did not reach significance in return to sport (73% vs 83%: P = .203), recurrence (9.3% vs 2.1%: P = .148), or revisions (6.8% vs 2.1%: P = .403). For on-track lesions there were 6 recurrences in IBR (6 of 74; 8.1%) and 1 recurrence in REMP (1 of 45; 2.2%).

Conclusions

Despite slightly worse pathology, patients with subcritical bone loss who undergo REMP experience similar short-term postoperative function to isolated IBR. Recurrence, revision, and return to sport favored REMP but this study was underpowered to show statistical significance. Recurrence was common following IBR, despite subcritical glenoid bone loss and primarily on-track lesions, suggesting that REMP can be considered in on-track lesions.

Level of Evidence

III, retrospective comparative study.

Arthroscopic remplissage is safe and effective: clinical and magnetic resonance results at a minimum 3 years of follow-up

BACKGROUND

Large Hill-Sachs lesions are considered a risk factor for recurrence of instability after arthroscopic Bankart repair alone. The aim of this study was to demonstrate that remplissage is a safe procedure that effectively reduces the risk of recurrent dislocations without causing fatty degeneration of the infraspinatus at medium-term follow-up.

METHODS

Patients who underwent arthroscopic Bankart repair and remplissage with a minimum 3 years of follow-up were included. Constant-Murley (CMS), American Shoulder and Elbow Surgeons (ASES), and Walch-Duplay scores were evaluated. Magnetic resonance imaging (MRI) was performed to detect the appearance of fatty infiltration inside the infraspinatus muscle, the percentage of the Hill-Sachs lesion filled by the tendon and its integration, and the onset of rotator cuff tears.

RESULTS

Thirteen patients (14 shoulders) with a mean follow-up of 55.93 (± 18.16) months were enrolled. The Walch-Duplay score was 95.00 [87.25-100.00], with a return to sport rate of 100%. Both the CMS and the ASES indicated excellent results. The affected shoulders showed a statistically significant reduction in active external rotation both with the arm at the side (ER1) and with the arm at 90° of abduction (ER2) (p = 0.0005 and p = 0.0010, respectively). A reduction in infraspinatus isometric strength was found for both ER1 and ER2, but this reduction was only statistically relevant in ER2 (p = 0.0342). There was a traumatic recurrence of instability in two cases (14.28%). MRI evaluation demonstrated an absence of adipose infiltration in 50% of cases and only a minimal amount in the remaining 50%. In 12 cases (85.72%), the capsulotenodesis completely filled the lesion and good tendon-bone integration was observed.

CONCLUSION

Arthroscopic remplissage provided successful clinical outcomes without fatty infiltration of the infraspinatus and with good healing of the tissues. The low risk of recurrence was associated with an objective limitation on active external rotation, but this did not influence the patients' daily or sports activities.

LEVEL OF EVIDENCE

Cohort study, level of evidence 3.

Limites da artroscopia na instabilidade anterior do ombro

Muito se discute sobre os limites do tratamento da instabilidade anterior do ombro por artroscopia. O avanço no entendimento das repercussões biomecânicas das lesões bipolares sobre a estabilidade do ombro, bem como na identificação de fatores relacionados ao maior risco de recidiva têm nos ajudado a definir, de forma mais apurada, os limites do reparo por via artroscópica.

Ressaltamos a importância de diferenciação entre perda óssea por erosão da glenoide (POAG) e fraturas da borda da glenoide, pois o prognóstico do tratamento diverge entre essas formas de falha óssea da glenoide. Neste contexto, entendemos que há três tipos de falha óssea: a) Bankart ósseo (fratura); b) combinada; e c) POAG, e abordaremos as opções de tratamento sugerido em cada situação.

Até há pouco tempo, a escolha do método cirúrgico era norteada basicamente pelo grau de acometimento ósseo. Com a evolução do conhecimento, da biomecânica das lesões bipolares e do conceito do glenoid track (trilho da glenoide), o ponto de corte da lesão crítica, vem sendo alterado com tendência de queda. Além das falhas ou perdas ósseas, outras variáveis foram adicionadas e tornaram a decisão mais complexa, porém um pouco mais objetiva.

O presente artigo de atualização tem como objetivo fazer uma breve revisão da anatomia com as principais lesões encontradas na instabilidade; abordar detalhes importantes na técnica cirúrgica artroscópica, em especial nos casos complexos, e trazer as evidências atuais sobre os assuntos de maior divergência, buscando guiar o cirurgião na tomada de decisão.

Computed Tomography-Based Preoperative Planning Provides a Pathology and Morphology-Specific Approach to Glenohumeral Instability With Bone Loss

PURPOSE

To use computed tomography (CT) to determine a reproducible method of coracoid measurement to compare the ability of the classic Latarjet technique and the congruent arc modification (CAM) to restore native glenoid diameter and to develop a preoperative planning algorithm for glenoid restoration with a goal of achieving an on-track shoulder.

METHODS

Coracoid dimensions were measured on multiplanar reconstructed shoulder CT scans of patients aged 18 to 45 years obtained between December 1, 2019, and March 13, 2020. Patients were excluded if CT demonstrated osteophyte formation, glenoid dysplasia, coracoid fracture, or tumor. The proportion of glenoid diameter able to be restored using classic Latarjet technique and CAM were calculated. A treatment algorithm was proposed considering the amount of bone loss present and coracoid dimensions.

RESULTS

Coracoid dimensions of 117 consecutive patients were measured and varied considerably (length: 17.5-31.8 mm, width: 9.1-20.5 mm, thickness: 6.1-15.7 mm). While most patients had harvestable coracoid length ≥20 mm (male: 96.3% vs female: 94.4%, P = .65), only 27.8% of female patients had coracoid thickness ≥10 mm. When comparing Latarjet techniques, there was no difference in the proportion of patients in whom 30% glenoid diameter could be fully restored, but CAM was able to restore at least 35% in more male and female patients (98.8% vs 79.0% and 100% vs 61.1%, respectively, P = .00001). Intra- and inter-rater reliability was excellent ( intraclass correlation coefficient ≥0.950 for all dimensions).

CONCLUSIONS

We describe a reliable method of measuring coracoid dimensions for preoperative planning of glenoid restoration. The classic Latarjet technique reliably restores the glenoid anteroposterior diameter with bone loss of up to 30%. The majority of female patients have coracoid thickness <10 mm, which may increase the risk of graft fracture when using CAM. The decision to use the classic Latarjet technique or CAM considers each individual's glenoid and coracoid dimensions with a goal of achieving an on-track shoulder.

CLINICAL RELEVANCE

Our reliable method of coracoid measurement demonstrated the differing abilities of the classic Latarjet and CAM to restore the native glenoid diameter. An evidence-based algorithm using these measurements was developed to assist in preoperative planning for glenohumeral instability in the setting of bone loss, with a goal of achieving an on-track shoulder. Alternative techniques may be considered if an on-track shoulder cannot be achieved with Latarjet.

All-Inside Knotless Remplissage Technique

Remplissage decreases the risk of recurrence after arthroscopic stabilization for recurrent anterior instability. Traditionally, the procedure requires accessing the subacromial space, which adds time and morbidity to the procedure. This Technical Note describes an all-inside technique for knotless remplissage with 2 interconnected anchors. By avoiding knot tying or accessing the subacromial space, the efficiency of the procedure is improved.

Characterization of Infraspinatus Tendon Anatomy: The Soft-Tissue Portion of Remplissage

Purpose

To characterize the morphology of the infraspinatus (IS) tendon and evaluate the bony anatomy of the humeral head (HH) to determine if there is a correlation between HH measurements and the amount of available IS tendon.

Methods

The superior-inferior width as well as the medial-lateral (M-L) length of the inferior and superior portions of the IS tendon were measured in 15 human cadaveric shoulders. Three measurements were then obtained for each corresponding humeral head: (1) anterior to posterior (A-P) distance, (2) midcoronal humeral head distance (MCHH), and (3) M-L distance. Pearson correlation coefficients (R) of tendon measurements relative to HH measurements were determined.

Results

The mean ± SD HH measurements were 44.3 ± 3.3 mm for A-P, 49.3 ± 3.4 mm at the MCHH, and 52.2 ± 3.4 mm in the M-L plane. The mean M-L length of the superior portion of the IS tendon was significantly different from the inferior portion (42.4 vs 31.0 mm, P < .0001). The mean ± SD width of the IS tendon was 19.4 ± 3.0mm. There was a statistically significant correlation (R = 0.58) between the M-L length of the superior IS tendon relative to the M-L HH distance (P < .05) and the A-P HH distance (P < .05).

Conclusions

The superior M-L IS tendon length was significantly greater than the inferior M-L length. The M-L HH and the AP HH distances were significantly correlated to the M-L length of the superior portion of the IS tendon. These relationships may provide an estimation of the length of available IS tendon to help guide the management of Hill-Sachs lesions (HSLs).

Clinical Relevance

Knowledge of the available IS length can help optimize the management of HSLs following anterior shoulder dislocation. If IS tendon M-L length is less than HSL M-L length, then remplissage may result in capsulomyodesis rather than tenodesis. Placement of the superior anchor in a position that is as superior as possible within the HSL defect will maximize the opportunity for IS tenodesis.

Utility of Allograft Talus as a Source for Grafting of Concurrent Humeral and Glenoid Defects Associated With Anterior Glenohumeral Instability: An Anthropometric Analysis

PURPOSE

To compare morphologic data of the talus using magnetic resonance images with previously reported values of the humeral head and the glenoid as a potential graft source for both the humeral head as well as glenoid reconstruction in the setting of concomitant glenoid and humeral head defects.

METHODS

All magnetic resonance images of the ankle were reviewed for assessment of the morphology and variation of the talus among individuals. Patients with post-traumatic, osteoarthritic, or surgical changes to the distal tibia about the mid- or hind- foot, or patients with incomplete medical records were excluded. Radiographic parameters that were measured included the maximum vertical height (MVH), the height to the talar neck, the radius of curvature (ROC) of the talar dome, ROC of the subtalar joint, and the maximum medial-to-lateral width of the talar dome. Demographic data also were collected on each individual. Statistical analysis was performed via a linear regression model with backwards elimination to determine which demographic data correlated most strongly with talar anthropometric values.

RESULTS

A total of 82 study patients met inclusion criteria (59 male, 23 female; mean age 40.91 ± 14.69 years). Sex was found have a positive correlation of the following talar dimensions: MVH (P = .039), talar dome ROC (P < .001), and subtalar joint ROC (p = 0.001). Height was the most positive correlation for medial-to-lateral width (P < .001), height to the talar neck (P = .004), and also correlate for MVH (P = .004). Body mass index was found to have multicollinearity and was therefore not used as a variable.

CONCLUSIONS

Allograft talus appears to be a viable graft, as demonstrated in this anthropometric study for both reconstruction of the glenoid and humeral head when cases of bipolar glenohumeral bone loss are present.

CLINICAL RELEVANCE

This study aims to further evaluate potential allograft donor sites for bipolar lesions.

Editorial Commentary: Preoperative 3-Dimensional Imaging for Shoulder Instability Is Vital for Determination of Off-Track Lesions and May Indicate Bankart Repair Plus Remplissage

The on- and off-track concept is gaining momentum for surgeons who treat patients with anterior shoulder instability. Preoperative imaging is critical for improving our outcomes. Determination of an off-track lesion prior to surgery using 3-dimensional computed tomography allows for improvement in outcomes by indicating remplissage. Intraoperative determination with the patient under anesthesia is not as good or as accurate. However, although Bankart repair plus remplissage shows good outcomes, bony procedures such as Latarjet, distal tibia allograft, and iliac crest or other bone graft procedures are preferred for large defects. Still, perhaps it is time to truly look at posterior adjuncts to anterior instability such as remplissage in patients who have off-track lesions, even with notable bipolar bone loss.

What Are the Effects of Remplissage on 6-Month Strength and Range of Motion After Arthroscopic Bankart Repair? A Multicenter Cohort Study

BACKGROUND

Patients who have undergone shoulder instability surgery are often allowed to return to sports, work, and high-level activity based largely on a time-based criterion of 6 months postoperatively. However, some believe that advancing activity after surgery should be dependent on the return of strength and range of motion (ROM).

HYPOTHESIS

There will be a significant loss of strength or ROM at 6 months after arthroscopic Bankart repair with remplissage compared with Bankart repair alone.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A total of 38 patients in a prospective multicenter study underwent arthroscopic Bankart repair with remplissage (33 males, 5 females; mean age, 27.0 ± 10.2 years; 82% with ≥2 dislocation events in the past year). Strength and ROM were assessed preoperatively and at 6 months after surgery. Results were compared with 104 matched patients who had undergone Bankart repair without remplissage, although all had radiographic evidence of a Hill-Sachs defect.

RESULTS

At 6 months, there were no patients in the remplissage group with anterior apprehension on physical examination. However, 26% had a ≥20° external rotation (ER) deficit with the elbow at the side, 42% had a ≥20° ER deficit with the elbow at 90° of abduction, and 5% had persistent weakness. Compared with matched patients who underwent only arthroscopic Bankart repair, the remplissage group had greater humeral bone loss and had a greater likelihood of a ≥20° ER deficit with the elbow at 90° of abduction (P = .004). Risk factors for a ≥20° ER deficit with the elbow at 90° of abduction were preoperative stiffness in the same plane (P = .02), while risk factors for a ≥20° ER deficit with the elbow at the side were increased number of inferior quadrant glenoid anchors (P = .003), increased patient age (P = .02), and preoperative side-to-side deficits in ER (P = .04). The only risk factor for postoperative ER weakness was preoperative ER weakness (P = .04), with no association with remplissage (P = .26).

CONCLUSION

Arthroscopic Bankart repair with remplissage did not result in significant strength deficits but increased the risk of ER stiffness in abduction compared with Bankart repair without remplissage at short-term follow-up.

Editorial Commentary: Glenoid Track Instability Management Score or Instability Severity Index Score-Will This Decrease Latarjet Abuse?

Open treatment of anterior shoulder instability using a coracoid transfer, such as the Latarjet procedure, is associated with low recurrence rates but with significant complications such as nerve injury, arthrosis, and graft osteolysis. However, an arthroscopic Bankart procedure, although less invasive and with a low complication rate, has the possibility of a higher recurrent instability rate. Scoring systems such as the Instability Severity Index Score, created to select patients for an arthroscopic Bankart procedure or coracoid transfer, have varying levels of success. Often, the scoring system selects a relatively high percentage of patients for the coracoid transfer, possibly undermining its widespread adoption. The relation between glenoid and humeral bone loss has produced the concept of "on-track" and "off-track," which impacts recurrent instability rates. Merging the on-track and off-track concept with the new Glenoid Track Instability Management Score may produce an algorithm that more accurately assesses the need for the Latarjet procedure or arthroscopic stabilization.

Arthroscopic Latarjet for Recurrent Shoulder Instability

Background and Objectives: The all-arthroscopic Latarjet (aL) procedure was introduced to manage recurrent shoulder instability. Our study aimed to report the outcomes of aL procedures with the Rowe, University of California-Los Angeles (UCLA), simple shoulder test (SST) scores, and range of motion (ROM) in external rotation at a minimum follow-up of 2 years. Material and Methods: A total of 44 patients presenting recurrent shoulder instability were managed with aL procedure. Clinical outcomes were assessed at a mean follow-up of 29.6 ± 6.9 months. The postoperative active ROM was measured and compared with the contralateral shoulder. The Rowe, UCLA, and SST scores were administered preoperatively and postoperatively. Results: No patients experienced infections or neuro-vascular injuries. Seven (15%) patients required revision surgery. After surgery, the external rotation was statistically lower compared to the contralateral shoulder, but it improved; clinical outcomes also improved in a statistically significant fashion. Conclusions: The aL produced good results in the management of recurrent shoulder instability, but the complication rate was still high even in the hands of expert arthroscopist.

Hill-Sachs Lesion Classification by the Glenoid Track Paradigm in Shoulder Instability: Poor Agreement Between 3-Dimensional Computed Tomographic and Arthroscopic Methods

PURPOSE

The purpose of this study was to determine the amount of agreement between preoperative 3-dimensional computed tomographic (3D-CT) and intraoperative arthroscopic classification of Hill-Sachs lesions (HSLs) according to the glenoid track (GT) paradigm.

METHODS

Records for patients treated surgically for anterior shoulder instability from a single surgeon's practice from August 2013 until March 2016 were retrospectively reviewed. Inclusion criteria were presence of an HSL, < 25% glenoid bone loss, bilateral 3D-CT, and arthroscopically recorded bone loss measurements. Records for patients with chronic dislocations or prior operations were excluded. Calculations by 3D-CT and arthroscopy were performed as follows: Hill-Sachs interval (HSI) was the distance from rotator cuff insertion to medial edge of the HSL; GT was 83% of the normal glenoid width minus any glenoid defect; on-track was HSI less than GT; off-track was HSI greater than GT.

RESULTS

Sixteen shoulders with HSL status determined as on- or off-track demonstrated agreement between the 2 methods in 10 of 16 cases (63%, Cohen's κ = 0.16). All 6 cases with disagreement were calculated as on-track by 3D-CT and off-track by arthroscopic measurement. The GT was larger as determined by 3D-CT measurement (22 ± 1 mm [21-24]) compared with arthroscopy (18 ± 1 mm [17-20], P = .002).

CONCLUSIONS

Preoperative 3D-CT showed slight agreement compared with intraoperative arthroscopic measurements in classifying HSL as on-track versus off-track in the GT paradigm; larger GT size by 3D-CT versus arthroscopy accounted for all discrepancies. Determination of off-track status based on preoperative 3D-CT versus determination with the arthroscopic method would result in fewer HSLs treated with remplissage if the GT treatment paradigm were followed. Surgeons using the GT paradigm to determine treatment of HSL by remplissage should recognize the potential for discordance between arthroscopic and radiographic measurements.

Editorial Commentary: Unsolved Problems in Shoulder Instability-The Dilemma of Bone Loss!

Bone loss in the setting of shoulder instability is an unsolved problem. Procedures restoring bone stock on the glenoid side vary from minimally invasive arthroscopic techniques of arthroscopic bone block procedures to traditional transposition of the coracoid or bone transplant. These techniques are evolving, and several tips and tricks have been optimized to improve outcomes and to reduce the risk of complications, even though the most terrible complication of transposition of the coracoid remains osteoarthritis in the young adult. The major innovation in the past few years has been the use of remplissage. The aim of our surgical procedures is to restore the anatomy as much as possible. Therefore, gentle handling of bone defects on both the humeral and glenoid sides by means of an arthroscopic bone block and combined remplissage seems to be the future of our surgical procedures.

Remplissage With Bankart Repair in Anterior Shoulder Instability: A Systematic Review of the Clinical and Cadaveric Literature

PURPOSE

To compare the clinical and biomechanical results of an arthroscopic Bankart repair alone with an arthroscopic Bankart repair combined with remplissage.

METHODS

A literature search was performed on May 1, 2018, in PubMed and Embase for studies comparing an isolated arthroscopic Bankart repair and an arthroscopic Bankart repair with remplissage. The quality of the studies was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach and the Cochrane Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) checklist. Results regarding failures, biomechanical properties, and shoulder function were extracted.

RESULTS

We included 13 studies (6 clinical and 7 biomechanical studies), and their overall quality was very low to low. In the biomechanical studies, adding a remplissage to the Bankart repair prevented engagement in all cadavers, resulted in more stiffness, and impaired the range of motion. Among clinical studies, all reported lower recurrence rates and most showed better shoulder function after a Bankart repair with remplissage compared with an isolated Bankart repair. The return-to-sport rates were mostly similar, whereas the loss of range of motion was often higher after a Bankart repair with remplissage.

CONCLUSIONS

The addition of a remplissage procedure to a Bankart repair for managing small to medium Hill-Sachs lesions might be beneficial in reducing the risk of recurrent instability and improving shoulder function, without increasing the risk of complications.

LEVEL OF EVIDENCE

Level III, systematic review of Level II and III studies.

Surgical decision making based on the on-track/off-track concept for anterior shoulder instability: a case-control study

Background

The purpose of this study was to assess the clinical outcomes of patients with anterior shoulder instability who underwent surgical treatment according to the on-track/off-track concept.

Methods

We retrospectively analyzed patients who underwent surgical treatment according to the glenoid track concept with a minimum of 2 years’ follow-up. By use of preoperative 3-dimensional computed tomography images, surgical options were selected: arthroscopic Bankart repair (ABR) for patients with on-track lesions and the Latarjet procedure or ABR with the remplissage procedure for patients with off-track lesions. The recurrence rate was assessed at 2-year follow-up after surgery.

Results

Among 92 patients enrolled in this study, 81 had on-track lesions and underwent ABR. Of the 11 patients with off-track lesions, 1 underwent ABR with the remplissage procedure and 10 underwent the Latarjet procedure. Recurrences occurred in 4 patients treated by ABR (5%), whereas no recurrences were observed in off-track cases treated by the remplissage or Latarjet procedure.

Conclusion

Clinical application of the on-track/off-track concept for determining surgical options in preoperative planning seems to be useful to prevent recurrent instability after surgery.

Magnetic resonance imaging predictors of shoulder instability in adolescents

BACKGROUND

Managing recurrent shoulder instability in an athlete of any age is challenging. The pediatric literature regarding recurrence of instability is difficult to interpret because of the variable treatment protocols and varying ages. The adult literature suggests that bone loss on the humerus, glenoid or both, as detected by CT, has high rates of recurrence following surgical intervention.

OBJECTIVE

The purpose of this study was to evaluate risk factors for recurrence following arthroscopic capsulorrhaphy in adolescent athletes using preoperative MR arthrograms.

MATERIALS AND METHODS

We reviewed a retrospective shoulder instability database for adolescents (age ≤18 years), who underwent an isolated arthroscopic capsulorrhaphy from 2006 to 2011. We recorded preoperative MRI measurements regarding the dimensions of the glenohumeral joint, as well as glenoid, humeral and labral pathologies. We performed statistical analysis to determine MRI findings that might have predicted recurrence of shoulder instability following capsulorrhaphy.

RESULTS

We reviewed a total of 50 patients (13-18 years) and found 22 patients (44%) to have recurrent instability following capsulorrhaphy. Presence of glenoid bone loss or a bipolar bone lesion (defined as bone loss on both the glenoid and humerus) significantly predicted recurrence of shoulder instability (both P=0.03). There was not a threshold size of glenoid bone loss or bipolar lesion that predicted recurrence. All remaining glenohumeral dimensions or presence or size of an isolated Hill-Sachs did not significantly predict recurrence of instability.

CONCLUSION

Athletes ≤18 years old have a high rate of failure following arthroscopic capsulorrhaphy in the presence of glenoid bone loss or a bipolar lesion on MRI. Surgeons should consider addressing these lesions in adolescent athletes with shoulder instability. Additionally, MRI is a valid imaging tool to diagnose and measure osseous lesions of the shoulder.

Clinical and Image Outcomes of the Hill-Sachs Injury Approach by the Remplissage Technique on the Anterior Shoulder Instability

OBJECTIVE

To evaluate the functional outcome of the remplissage technique, the healing of the capsulotenodesis of the infraspinatus tendon in Hill-Sachs lesion, and the degree of fatty infiltration of the infraspinatus muscle and its postoperative strength.

METHODS

Twenty-five patients with recurrent anterior dislocation of the shoulder and Hill-Sachs lesion with a Hardy index > 20% who underwent the remplissage arthroscopic technique were evaluated with a minimum follow-up of 1 year. Patients underwent a clinical evaluation (Carter-Rowe and Walch-Duplay functional scores, measurement of range of motion and strength) and a magnetic resonance imaging (MRI) exam on the operated shoulder.

RESULTS

Eighty-eight percent and 92% of the patients had good or excellent scores in the functional assessments of the Carter-Rowe and Walch-Duplay scores, respectively. A mean difference of - 1 kg in the strength of the operated limb was observed when compared with the contralateral limb ( p  < 0.001), as well as a mean difference of 10° in external rotation 1 and 2 ( p  < 0.001), also compared with the contralateral side. All of the patients who underwent an MRI exam presented high-grade filling of the Hill-Sachs lesion by capsulotenodesis, as well as absence of or minimal fatty infiltration in the infraspinatus muscle.

CONCLUSION

The remplissage technique had good/excellent functional score results, despite the discrete, albeit statistically significant, loss of strength and of external rotation amplitude. Successful capsulotenodesis healing and filling of the Hill-Sachs defect were demonstrated.

Arthroscopic Remplissage for Anterior Shoulder Instability: A Systematic Review of Clinical and Biomechanical Studies

PURPOSE

To examine the clinical outcomes and biomechanical data supporting the use of the remplissage procedure.

METHODS

A query of the Embase, PubMed, Scopus, and Web of Science databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines from 2000 to 2017. Data were extracted from included studies for a qualitative review of both clinical and biomechanical outcomes.

RESULTS

After review, 18 clinical and 10 biomechanical studies were available for analysis; 10 of 18 clinical studies (55.6%) were Level IV evidence. Within the clinical studies, there were 567 patients (570 shoulders) evaluated with follow-up ranging from 6 to 180 months. Overall, 5.8% of shoulders (33 of 570) displayed recurrent instability after arthroscopic remplissage. Of the shoulders with recurrent instability, 42.4% of shoulders (14 of 33) underwent further surgical management. In all studies evaluating pre- and postoperative patient-reported outcomes, the arthroscopic remplissage procedure improved patient-reported outcomes a statistically significant amount postoperatively. Within individual clinical studies, external rotation with the arm in neutral was the most consistently limited range of motion (ROM) parameter, with deficits compared with the contralateral shoulder ranging from 9° to 14°. Biomechanical analysis appeared to corroborate the clinical results, although significant conclusions were limited by heterogeneity of reporting.

CONCLUSIONS

Arthroscopic remplissage performed in conjunction with arthroscopic Bankart repair is a safe and effective procedure for patients with engaging Hill-Sachs lesions and subcritical glenoid bone loss. Although both the included clinical and biomechanical studies would suggest minimal changes in glenohumeral ROM following the remplissage procedure, strong conclusions are limited by the heterogeneity in reporting ROM data and lack of comparative studies.

LEVEL OF EVIDENCE

IV, systematic review.

Remplissage Using Interconnected Knotless Anchors: Superior Biomechanical Properties to a Knotted Technique?

PURPOSE

To evaluate the biomechanical fixation strength and gap formation of 2 different remplissage fixation methods (double pulley knotted construct and interconnected knotless repair construct) in cadaver specimens.

METHODS

Seven matched pairs of human cadaveric shoulders were used for testing (mean age, 56 ± 10 years). A shoulder from each matched pair was randomly selected to receive a Hill-Sachs remplissage using either a knotted (No. 2 FiberWire double pulley with 3.0-mm SutureTak anchors) or knotless (coreless No. 2 FiberWire interconnected between 3.9-mm knotless CorkScrew anchors) double mattress construct. The tendon was cycled between 10 and 100 N at 1 Hz for 100 cycles, followed by a single-cycle pull to failure at 33 mm/s. Cyclic displacement, load to clinical failure (5 mm), yield load, and mode of failure were recorded.

RESULTS

Neither construct demonstrated clinical failure under cyclic loading. Load to clinical failure was higher for the knotless repair than that of the knotted repair (788 ± 162 N vs 488 ± 227 N; P = .003). The yield load was higher for the knotless repair than that of the knotted repair (1,080 ± 298 N vs 591 ± 265 N; P = .008). The most common failure mode for the knotted repair was knot failure or tendon tearing, whereas the failure mode for the knotless repair was by anchor pull-out or tendon tear with no failures occurring via the interconnected suture construct mechanism.

CONCLUSIONS

In this biomechanical study comparing cyclic and ultimate loading for 2 double mattress remplissage repairs, the construct using interconnected, knotless sutures outperformed the knotted construct. No failure of the interconnected suture construct mechanism by slippage or breakage was observed in the knotless group.

CLINICAL RELEVANCE

The use of the interconnected knotless suture technique might improve the biomechanical strength of arthroscopic remplissage repairs in treating shoulder instability.

Isolated arthroscopic Bankart repair vs. Bankart repair with "remplissage" for anterior shoulder instability with engaging Hill-Sachs lesion: A meta-analysis

INTRODUCTION

Arthroscopic "remplissage" of a Hill-Sachs lesion (HSL) associated with a Bankart repair (BR) has been recently introduced as a surgical option to treat chronic anterior shoulder instability. The purpose of this study was to analyze the current literature comparing results of isolated BR versus BR+remplissage in the treatment of anterior shoulder instability with engaging HSL.

HYPOTHESIS

BR+remplissage are superior to isolated BR in the management of anterior shoulder instability with engaging HSL.

MATERIAL AND METHODS

Four electronic databases were searched for original, English-language studies comparing BR vs. BR+remplissage procedures. During the inclusion process we used international Preferred Reporting Items for Systematic review and Meta-Analysis (PRISMA) guidelines and the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. Our data were extracted from the text, tables and figures of the selected studies.

RESULTS

Three comparative studies were identified, which included 146 patients; 74 of them underwent isolated BR, and 72 BR+remplissage procedure. The isolated BR results in significantly higher risk of recurrence and redislocation. There was no significant difference in the rates of reoperation and time to return to sport between the two procedures. Rowe and UCLA scores were lower in the isolated BR group compared with the BR+remplissage group.

DISCUSSION

This meta-analysis demonstrates the superiority of BR+remplissage procedure vs. isolated BR in the management of anterior shoulder instability with engaging HSL and with up to 25% glenoid bone loss regarding redislocation rate, recurrent instability and functional scores. A comparison between postoperative range of motion and particularly external rotation was not able to be formally assessed in this study.

LEVEL OF EVIDENCE

III.

Editorial Commentary: Use Remplissage as a "Fill In" for Latarjet in Patients With Shoulder Instability and Hill Sachs Lesions

Remplissage minimizes recurrence and confers minimal motion loss when applied to glenoid defects up to 20% and humeral loss up to 40% in patients with shoulder instability. However, variability in the reporting of volume of both glenoid and humeral head bone loss deters the formulation of distinct thresholds for indications and contraindication for remplissage. However, there appears to be little downside in the performance of this "biologic" solution to Hill-Sachs lesions.

Recurrence Rate of Instability After Remplissage for Treatment of Traumatic Anterior Shoulder Instability: A Systematic Review in Treatment of Subcritical Glenoid Bone Loss

PURPOSE

To report outcomes after arthroscopic remplissage in patients with anterior shoulder instability and subcritical glenoid bone loss, specifically regarding recurrence of instability, return to sport, and changes in range of motion.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used to perform a search using the PubMed, Embase, Cochrane Library, and Scopus databases. Forest plots were used to evaluate the overall values for recurrent instability, change in external rotation, and return to sport after arthroscopic Bankart repair with or without remplissage. The Methodological Index for Non-randomized Studies and Risk of Bias in Nonrandomized Studies-Interventions checklist were used to evaluate bias.

RESULTS

Twenty-two articles met the inclusion and exclusion criteria. The Methodological Index for Non-randomized Studies and Risk of Bias in Nonrandomized Studies-Interventions checklists deemed studies as acceptable quality with low bias. Among 694 patients (522 male and 106 female patients) undergoing remplissage, the mean age was 28.3 ± 5.3 years and the mean duration of follow-up was 32.5 ± 13.9 months. The recurrence rate of instability ranged from 0% to 20%. The change in external rotation in 90° of abduction ranged from -11.3° to -1.0°, and the change in external rotation with the arm fully adducted ranged from -8.0° to +4.5°. The overall rate of return to sport ranged from 56.9% to 100% after remplissage. The rate of return to sport at the preinjury level ranged from 41.7% to 100%. In addition, arthroscopic remplissage in addition to Bankart repair had a reduced odds of recurrent instability developing, ranging from 0.07 to 0.88, when compared with isolated Bankart repair.

CONCLUSIONS

Arthroscopic remplissage combined with Bankart repair is an effective procedure in the treatment of patients with engaging Hill-Sachs lesions and minimal glenoid bone loss. Patients can expect favorable rates of recurrent instability with a negligible loss of external rotation when compared with isolated Bankart repair. Treatment algorithms may be updated to include this procedure for engaging Hill-Sachs lesions, measuring between 20% and 40% in volume, with subcritical (<20%) glenoid bone loss.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III and IV studies.

Top orthopedic sports medicine procedures

Orthopedic sports medicine is a subspecialty of Orthopedics that focuses on managing pathological conditions of the musculoskeletal system arising from sports practice. When dealing with athletes, timing is the most difficult issue to face. Typically, athletes aim to return to play as soon as possible and at the pre-injury level. This means that management should be optimized to combine the need for prompt return to sport and to the biologic healing time of the musculo-skeletal. This poses a great challenge to sport medicine surgeons, who need to follow with attention to the latest scientific evidence to offer their patients the best available treatment options. We briefly review the most commonly performed orthopedic sports medicine procedures, outlining the presently available scientific evidence on their indications and outcomes.

Managing Bony Defects of the Shoulder Joint that Occur in Association with Dislocation

Background

Defects to the articular surface of the humeral head have been known to be associated with shoulder dislocation since the 19^th century. It wasn't until 1934 that the first description of the ubiquitous compression fracture of the posterolateral humeral head that occurs with traumatic anterior instability appeared. From 1940, this defect became referred to as a Hill-Sachs lesion after the investigators who reported the condition. The significance of, and therefore treatment of, these and other such bony defects around the shoulder joint has been hotly debated.

Methods

We reviewed the available current literature to determine and report on the most up to date concepts and treatment techniques being used to manage bony defects of the shoulder.

Results

Numerous surgical options have been proposed to manage bony defects of the shoulder, including a variety of defect-filling procedures, with good outcomes. However, the small numbers and diversity of case mix makes for difficult comparisons.

Conclusion

We are currently developing a greater appreciation of how both the humeral and glenoid defects interact and therefore should be assessed and addressed simultaneously in order to improve patient outcomes. More research and collaboration is needed to determine the optimal method of assessing and managing these patients.

Does the Arthroscopic Latarjet Procedure Effectively Correct "Off-Track" Hill-Sachs Lesions?

BACKGROUND

The glenoid track concept describes the dynamic interaction of bipolar bone loss in anterior glenohumeral instability. Initial studies have successfully demonstrated this concept's application in clinical populations. In clinical practice, the Latarjet procedure is commonly the preferred treatment in addressing "off-track" Hill-Sachs lesions. The effectiveness of this procedure in restoring such lesions to an "on-track" state, however, has not yet been evaluated or described in the literature.

HYPOTHESIS

The Latarjet procedure would transform "off-track" Hill-Sachs lesions to "on-track" lesions. Lesions would remain "on-track" during follow-up, despite glenoid remodeling.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients with "off-track" Hill-Sachs lesions treated with the arthroscopic Latarjet procedure between March 2013 and May 2014 were included. Glenoid track and coracoid graft contact surface area measurements using 3-dimensional computed tomography (3D-CT) were performed preoperatively and at 6-week, 6-month, and at least 12-month (final) follow-up. The mean final follow-up was 23 months. The glenoid diameter, as a percentage of the native glenoid, was also calculated from this imaging.

RESULTS

Twenty-six patients met the inclusion criteria. 3D-CT scans were available for all patients preoperatively and postoperatively, with 21 patients (81%) undergoing 6-month follow-up CT and 19 patients (73%) undergoing final follow-up CT. Hill-Sachs lesions remained "on-track" at all follow-up time points. The mean glenoid diameter changed significantly from 84.6% preoperatively to 122.8% at 6 weeks ( P < .001) and from 120.5% at 6 months to 113.9% at final follow-up ( P = .005). This was also reflected in significant remodeling seen in the coracoid graft articular contact area (6 weeks to 6 months, P = .024; 6 months to final follow-up, P = .002). This persisting glenoid arc enlargement at final follow-up avoided "off-track" Hill-Sachs lesions in 6 of 19 patients (32%), which would otherwise have occurred had the coracoid graft remodeled to native glenoid dimensions.

CONCLUSION

The Latarjet procedure provides an effective treatment for "off-track" engaging Hill-Sachs lesions, despite an evident glenoid remodeling process. At a mean of 23 months postoperatively, a mean persisting enlargement of the glenoid arc of 14% beyond native dimensions remained, avoiding a recurrent "off-track" lesion in 32% of patients, which would otherwise have occurred with complete remodeling.

Arthroscopic Bankart Repair for the Management of Anterior Shoulder Instability: Indications and Outcomes

PURPOSE OF REVIEW

Arthroscopic Bankart repair is commonly utilized for shoulder stabilization in patients with anterior shoulder instability with minimum glenoid bone loss. The purpose of this review is to provide the indications, surgical technique, complications, and recent outcomes in arthroscopic Bankart repair for shoulder instability.

RECENT FINDINGS

Improvements in arthroscopic techniques have led to better patient outcomes, as well as an improved understanding of the pathoanatomy of instability. More recent studies have shown that one of the potential failures of primary arthroscopic repair may be due to unaddressed bone loss. This underscores the importance of evaluating glenoid bone loss and proper patient selection for this procedure to ensure successful outcome. When indicated, arthroscopic stabilization is the treatment of choice for many surgeons due to its lower morbidity and low overall complication rate. Future work must focus on longer-term outcomes in patients undergoing arthroscopic Bankart repair, as well as the clinical outcomes of new fixation techniques, augmentation techniques, and the effect of glenoid bone loss in outcome.

The glenoid track: a review of the clinical relevance, method of calculation and current evidence behind this method

In the setting of bipolar bone injury, orthopedic surgeons are currently making use of the glenoid track method to guide surgical management. Using preoperative CT or MR imaging, this method allows the identification of patients who are more likely to fail a primary capsuloligamentous Bankart repair. As the glenoid track method becomes increasingly used in preoperative planning, it is important for the radiologist to become familiar with its concept and method of calculation. This review article aims to concisely summarize the current literature and the clinical implications of the glenoid track method.

Applying the Glenoid Track Concept in the Management of Patients with Anterior Shoulder Instability

PURPOSE OF REVIEW

The purpose of this paper is to evaluate the recent evolution in the treatment of anterior shoulder instability and the dynamic interaction between the glenoid and Hill-Sachs lesion.

RECENT FINDINGS

Through the glenoid track concept, glenoid- and humeral-sided bone loss are evolving away from being approached as separate entities. Recent cadaveric studies have validated the glenoid track concept. Moreover, a recent clinical study has demonstrated a much higher rate of failure after arthroscopic Bankart repair for shoulders that were off track. The glenoid track concept is a useful tool in evaluating patients with anterior shoulder instability. Shoulders that are off track may require more than a simple arthroscopic Bankart, and the addition of a remplissage or bony transfer may be considered.

Editorial Commentary: Off-Track Hill-Sachs Lesions in Adolescents With Multiple Anterior Dislocations: The Case for Stabilizing Adolescent First-Time Dislocators

Recurrent anterior dislocations in adolescents reveal a high rate of off-track Hill-Sachs lesions, much higher than in adults. This new information makes a strong case in favor of arthroscopic Bankart repair for adolescents with a first-time anterior dislocation of the shoulder.

Bipolar Bone Loss in Patients With Anterior Shoulder Dislocation: A Comparison of Adolescents Versus Adult Patients

PURPOSE

To compare bipolar bone loss by evaluating the degree of glenoid bone loss, Hill-Sachs lesion size, and glenoid track in adolescents and adults with shoulder dislocations.

METHODS

We performed a retrospective review between 2012 and 2016 of surgical and nonsurgical patients with a history of anterior shoulder dislocations (primary or recurrent) who underwent magnetic resonance imaging of the affected shoulder. The exclusion criteria included multidirectional instability, prior surgery, and posterior dislocation. Patients were grouped into 2 groups: adolescents (aged 10-19 years) and adults (aged ≥20 years). The groups were compared regarding measures of glenoid bone loss (best-fit circle technique) and Hill-Sachs lesion size (medial margin of rotator cuff footprint to medial margin of Hill-Sachs lesion). If the medial margin of a Hill-Sachs lesion was within the glenoid track, it was defined as on track; if it was more medial than the glenoid track, it was defined as off track.

RESULTS

We identified 45 adolescents (mean age, 16.1 years) and 30 adults (mean age, 28.9 years) with anterior shoulder dislocations. There was no significant difference in percentage of bone loss between adolescents (mean, 8.4%) and adults (mean, 9.9%; P = .23). There was no significant difference in Hill-Sachs lesion size between adolescents (mean, 12.7 mm) and adults (mean, 9.9 mm; P = .12). There were 12 patients with off-track lesions. Off-track lesions were present in 11 of 45 adolescents (24.4%) and 1 of 30 adults (3.3%). Adolescents had an increased risk of having an off-track lesion (odds ratio, 9.38; 95% confidence interval, 1.14-77.1). A subgroup analysis identified multiple dislocations as an independent risk factor for an off-track lesion (odds ratio, 4.15; 95% confidence interval, 0.85-20.23).

CONCLUSIONS

This study shows that adolescence and a history of multiple dislocations are independent risk factors for a greater likelihood of glenoid off-track lesions. The findings support the use of bipolar assessment of shoulder dislocators, especially in adolescents and multiple dislocators.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Arthroscopic Bone Grafting of the Humeral Head for Treatment of a Deep Hill-Sachs Lesion

Recurrent anterior shoulder dislocation often leads to the presence of a Hill-Sachs lesion. A large Hill-Sachs lesion compromises shoulder stability and should be addressed with bone augmentation when it is too deep. Here, we introduce a method of arthroscopic bone grafting of the humeral head for the treatment of a deep Hill-Sachs lesion in patients with anterior shoulder instability. Our indication for this procedure is a deep off-track Hill-Sachs lesion measuring at least 8 mm in depth and 10 mm in width. The main steps of this procedure include graft placement via special shoulder bone grafting instruments, graft suspension fixation using suture anchors, and bone fragment compression using the infraspinatus tendon. We routinely use this technique in combined treatment procedures for complicated anterior shoulder instability.

The Tripod-Pulley Technique for Arthroscopic Remplissage in Engaging Hill-Sachs Lesions

Arthroscopic Bankart repair is now a well-established technique for the treatment of shoulder instability. However, failure rates are considerable when significant bony defects are not addressed. Hill-Sachs lesions, present in the vast majority of those with recurrent anterior instability, when of significant dimension and location, may account for some of these failures. The remplissage procedure involves capsulotenodesis of the posterior capsule and the infraspinatus tendon to fill the Hill-Sachs lesion. "Double-pulley" remplissage is a transtendinous technique that has been described elsewhere and that may simplify the procedure. We present a modification of this technique, the "tripod-pulley" technique, which we feel may potentiate healing of the Hills-Sachs lesions of the capsule and infraspinatus by increasing the surface contact area. At the same time, this technique minimizes the risk of potential damage to the infraspinatus as it uses 2.3-mm "all-suture" anchors.

Auld Lang Syne: A New Year Brings Awards and a New Cover

"Auld Lang Syne," a traditional poem used to welcome the New Year, asks rhetorically, "Should old acquaintance be forgot, and never brought to mind?" At Arthroscopy, the answer is a resounding no. We view January as an opportunity to celebrate the abundance and excellence of research published in Arthroscopy. This year, we have decided to spread our applause, approval, and appreciation to recognize both award winners and runners-up, whose distinction in research epitomizes the bounty that is Arthroscopy. In addition, we proudly introduce a new cover.