Arthroscopic Anterior Stabilization Research Articles

To Remplissage or not to Remplissage Part 2: Recurrent Instability After Primary Stabilization Surgery (RIPSS) Risk Tool Assesses Preoperative Failure Rates in On-track Shoulders Undergoing Primary Arthroscopic Anterior Stabilization with or without Remplissage Augmentation

Objectives: Given the high rates of recurrent instability following the initial arthroscopic Bankart repair (ABR), it is crucial to provide recommendations for appropriate surgical interventions for patients at a higher risk of experiencing recurring instability. In Part 1 of the study, it was discovered that on-track Hill-Sachs lesions (HSL) with specific prognostic factors (i.e., younger age, increased shoulder laxity, lower DTD, and 2+ preoperative instability events) were associated with a greater risk of failure. Therefore, the objective of Part 2 was to develop a risk assessment tool that takes into account significant prognostic factors for recurrent shoulder instability following primary ABR and evaluate the role of remplissage augmentation given a patient’s risk profile. Methods: We retrospectively reviewed prospectively collected data of consecutive patients aged 14-40 who underwent either ABR (arthroscopic Bankart repair) or ABR+R (ABR with remplissage) procedures between 2013 and 2021 for anterior glenohumeral instability. Preoperative magnetic resonance imaging was used to determine the values of glenoid bone loss, Hills-Sachs Interval (HSI), glenoid track (GT), and distance-to-dislocation (DTD). On-track lesions have a distance-to-dislocation (DTD) value greater than zero. In addition, within the category of on-track lesions, there is a subset known as “near-track” lesions, with a DTD ranging from 0 to 10 mm. Capsuloligamentous laxity scores were categorized according to hyperlaxity status, defined as external rotation greater than 85 degrees and/or grade 2+ posterior and inferior load-and-shift on examination under anesthesia. Recurrent shoulder instability was defined as recurrent dislocation and/or subjective subluxation postoperatively. Patients were excluded if the indexed surgery was a revision procedure, < 2-year follow-up, or glenoid bone loss (GBL) >20%. A final multivariate survival analysis was constructed using categorical prognostic factors (i.e., patient age, “near-track” status, hyperlaxity, and 2+ preoperative instability episodes) identified in Part 1, while adjusting for GBL. Although contact athlete status was not identified as a significant predictor of recurrent shoulder instability in Part 1, the final model stratified by contact athlete status given its established importance in prior literature. Multivariate hazard ratio estimates were utilized to create a risk assessment tool and correlated with patient-specific risk estimates via post-estimation analysis. Results: One-hundred-and-fifty-five patients were included for analysis (ABR: 116 | ABR+R: 39) with an average age of 21.6 ± 6.2 years and an average follow-up of 5.1 ± 2.0 years (range: 2.0 – 8.7 yrs). Patients with near-track lesions had a three-fold higher risk of recurrent instability (Hazard Ratio [HR]: 2.5, p = 0.03) compared to on-track HSL with DTD > 10mm. Individuals with evidence of hyperlaxity exhibited a five-fold increased risk (HR: 5.4, p=0.03) relative to patients without hyperlaxity. Younger patient groups had twice the risk of recurrent shoulder instability (HR: 2.2, p=0.003) compared to older adjacent groups. Patients with two or more preoperative recurrent instability episodes faced a four-times greater risk (HR: 4.2, p=0.004) for recurrent shoulder instability compared to patients who experienced a single instability event preoperatively. Lastly, patients who underwent primary ABR only had almost 10-times greater risk of recurrent shoulder instability (HR: 9.5, p=0.002) than those who underwent primary ABR+R. The Recurrent Instability after Primary Shoulder Stabilization (RIPSS) risk assessment score considers patient age, near-track status, hyperlaxity, preoperative instability episodes, and surgical technique (ABR vs. ABR+R) as important prognostic indicators, Table 2. The RIPSS score was created with risk stratifying subgroups: Low-risk (0 – 2), Moderate-risk (3 – 6), High-risk (7 – 9), and Extreme-risk (10+). Figure 1 illustrates a strong correlation between patient RIPSS scores with patient-specific hazard ratio estimates derived from the multivariate Cox regression modeling computed in “To Remplissage or not to Remplissage Part 1”. According to RIPSS score subgroups, recurrent shoulder instability rates range from 4.3% among low-risk groups to 54.6% among extreme-risk groups, Figure 1. Conclusions: Patients with a low-risk RIPSS score without ABR+R may not benefit from remplissage augmentation. Their risk for recurrent instability would remain low despite the addition of remplissage. However, patients with a high- or extreme-risk RIPSS score prior to considering ARB+R would likely benefit from remplissage supplementation. The RIPSS score may be an effective risk assessment tool that may help identify patients who may benefit from a primary Bankart repair with remplissage augmentation. The risk assessment tool developed may optimize surgical treatment and allow physicians to determine patient risk scores with and without remplissage augmentation.

Concomitant Biceps Tenodesis Does Not Portend Inferior Outcomes After Anterior Glenohumeral Stabilization

Background: Military patients are known to suffer disproportionately high rates of glenohumeral instability as well as superior labrum anterior to posterior (SLAP) tears. Additionally, a concomitant SLAP tear is frequently observed in patients with anterior shoulder instability. Even though biceps tenodesis has been demonstrated to produce superior outcomes to SLAP repair in military patients with isolated SLAP lesions, no existing studies have reported on outcomes after simultaneous tenodesis and anterior labral repair in patients with co-existing abnormalities. Purpose: To evaluate outcomes after simultaneous arthroscopic-assisted subpectoral biceps tenodesis and anterior labral repair in military patients younger than 40 years. We also sought to compare these outcomes with those after repair of an isolated anterior labral tear. Study Design: Cohort study; Level of evidence, 3. Methods: This study is a retrospective analysis of all military patients younger than 40 years from a single base who underwent arthroscopic anterior glenohumeral stabilization with or without concomitant biceps tenodesis between January 2010 and December 2019. Patients with glenoid bone loss of >13.5% were not eligible for inclusion. Outcome measures including the visual analog scale (VAS) for pain, the Single Assessment Numeric Evaluation (SANE), the American Shoulder and Elbow Surgeons (ASES) shoulder score, the Rowe instability score, and range of motion were administered preoperatively and postoperatively, and scores were compared between groups. Results: A total of 82 patients met inclusion criteria for the study. All patients were active-duty service members at the time of surgery. The mean follow-up was 87.75 ± 27.05 months in the repair + tenodesis group and 94.07 ± 28.72 months in the isolated repair group (P = .3085). Patients who underwent repair + tenodesis had significantly worse preoperative VAS pain (6.85 ± 1.86 vs 5.02 ± 2.07, respectively; P < .001), ASES (51.78 ± 11.89 vs 62.43 ± 12.35, respectively; P = .0002), and Rowe (26.75 ± 7.81 vs 37.26 ± 14.91, respectively; P = .0002) scores than patients who underwent isolated repair. Both groups experienced significant improvements in outcome scores postoperatively (P < .0001 for all), and there were no statistically significant differences in postoperative outcome scores or range of motion between groups. There were no differences in the percentage of patients who achieved the minimal clinically important difference, substantial clinical benefit, and patient acceptable symptom state for the VAS pain, SANE, ASES, and Rowe scores between groups. Overall, 37 of the 40 (92.50%) patients in the repair + tenodesis group and 40 of the 42 (95.24%) patients in the isolated repair group returned to unrestricted active-duty military service (P = .6045). In addition, 38 (95.00%) patients in the repair + tenodesis group and 40 (95.24%) patients in the isolated repair group returned to preinjury levels of sporting activity (P = .9600). There were no significant differences in the number of failures, revision surgical procedures, or patients discharged from the military between groups (P = .9421, P = .9400, and P = .6045, respectively). Conclusion: The findings of this study indicate that simultaneous biceps tenodesis and labral repair was a viable treatment option for the management of concomitant SLAP and anterior labral lesions in young, active military patients younger than 40 years.

Beach-Chair Versus Lateral Decubitus Positioning for Primary Arthroscopic Anterior Shoulder Stabilization: A Consecutive Series of 641 Shoulders

Background: There are limited data comparing the beach-chair (BC) versus lateral decubitus (LD) position for arthroscopic anterior shoulder stabilization. Purpose: To identify predictors of instability recurrence and revision after anterior shoulder stabilization and evaluate surgical position and glenoid bone loss as independent predictors of recurrence and revision at short- and midterm follow-ups. Study Design: Cohort study; Level of evidence, 3. Methods: A consecutive series of 641 arthroscopic anterior stabilization procedures were performed from 2005 to 2019. All shoulders were evaluated for glenohumeral bone loss on magnetic resonance imaging. The primary outcomes of interest were recurrence and revision. Multivariable logistic regression models were used to assess the relationships of outcomes with age, position, glenoid bone loss group, and track. Results: A total of 641 shoulders with a mean age of 22.3 years (SD, 4.45 years) underwent stabilization and were followed for a mean of 6 years. The overall 1-year recurrent instability rate was 3.3% (21/641) and the revision rate was 2.8% (18/641). At 1 year, recurrence was observed in 2.3% (11/487) and 6.5% (10/154) of BC and LD shoulders, respectively. The 5-year recurrence and revision rates were 15.7% (60/383) and 12.8% (49/383), respectively. At 5 years, recurrence was observed in 16.4% (48/293) and 13.3% (12/90) of BC and LD shoulders, respectively. Multivariable modeling demonstrated that surgical position was not associated with a risk of recurrence after 1 year (odds ratio [OR] for LD vs BC, 1.39; P = .56) and 5 years (OR for LD vs BC, 1.32; P = .43), although younger age at index surgery was associated with a higher risk of instability recurrence (OR, 1.73 per SD [4.1 years] decrease in age; P < .03). After 1 and 5 years, surgical position results were similar in a separate multivariable logistic regression model of revision surgery as the dependent variable, when adjusted for age, surgical position, bone loss group, and track. At 5 years, younger age was an independent risk factor for revision: OR 1.68 per SD (4.1 years) decrease in age (P < .05). Conclusion: Among fellowship-trained orthopaedic surgeons, there was no difference in rates of recurrence and revision surgery after performing arthroscopic anterior stabilization in either the BC or the LD position at 1- and 5-year follow-ups. In multivariable analysis, younger age, but not surgical position, was an independent risk factor for recurrence.

Outcomes of total shoulder arthroplasty in patients with prior anterior shoulder instability: minimum 5-year follow-up

Patients with a history of anterior shoulder instability (ASI) commonly progress to glenohumeral arthritis or even "dislocation arthropathy" and often require total shoulder arthroplasty (TSA). The purposes of this study were to 1) report patient reported outcomes (PROs) after TSA in patients with a history of ASI, 2) compare TSA outcomes of those whose ASI was managed operatively versus those managed nonoperatively, and 3) report PROs of TSA in patients who previously underwent arthroscopic versus open ASI management. Patients were included if they had a history of ASI and were at least 5 years out from TSA performed by a single surgeon between 10/2005 and 01/2017. Exclusion criteria included prior rotator cuff repair, hemi-arthroplasty, or glenohumeral joint infection prior to index TSA. Patients were separated into two groups, those with previous operatively managed ASI and those whose ASI was treated nonoperatively. Prospectively collected demographic, surgical, and subjective data were retrospectively reviewed. PROs utilized were the ASES score, SANE, QuickDASH, SF-12 PCS. Failure was defined as revision TSA surgery, conversion to reverse TSA, or prosthetic joint infection. Kaplan-Meier survivorship analysis was performed. 36 patients (27 male, 9 female) with a mean age of 56.4 years (range, 18.8-72.2) were included. Patients in the operative ASI group were younger than those in the nonoperative ASI group (50.6 vs 64.0 years, p<.001). Operative ASI patients underwent 10 open and 11 arthroscopic anterior stabilization surgeries prior to their TSA (mean, 2; range, 1-4). 6 of 21 (28.6%) TSAs failed in patients with operative ASI while there were no failures in the nonoperative ASI group (p=0.03). Follow-up was obtained in 28 of 30 (93%) eligible patients at an average of 7.45 years (range, 5.0-13.6). In the collective cohort, ASES, SANE, QuickDASH, and SF-12 PCS scores significantly improved with no differences in the postoperative PROs between the two groups. No significant differences were found when comparing PROs between prior open and prior arthroscopic ASI procedures or when comparing the number of prior ASI procedures. Kaplan-Meier analysis demonstrated 79% 5-year survivorship in patients with prior ASI surgery and 100% survivorship in nonoperatively managed ASI patients (p=.030). At mid-term follow-up, patients with a history of prior ASI undergoing TSA can expect continued improvement in function compared to preoperative values. However, TSA survivorship is decreased in patients with a history of ASI surgery compared to those without prior surgery.

A High Rate of Return to Running Is Seen After Both Arthroscopic and Open Shoulder Surgery

To determine the percentage of patients who report the ability to run 1 mile at various time points after arthroscopic and open shoulder surgery. We performed a retrospective review of prospectively collected data for all active-duty military patients aged 18 to 45 years who underwent shoulder surgery at a single institution over a 2-year period. The rehabilitation protocol discouraged running before 3 months, but all patients were able to return to unrestricted running at 3 months postoperatively. Patients were excluded if they lacked 1-year follow-up data. Parameters collected included demographic information and validated patient-reported outcome measures at the preoperative and short-term postoperative visits, as well as patients' ability to run at least 1 mile postoperatively. A total of 126patients were identified who underwent shoulder surgery with return-to-running data. Compared with baseline, significant improvements in patient-reported outcomes were shown at 1 and 2 years postoperatively (P= .001). The percentage of patients reporting the ability to run 1 mile postoperatively was 59% at 3 months, 74% at 4.5 months, 79% at 6 months, 83% at 12 months, and 91% at 24 months. There was no significant difference in patients undergoing shoulder surgery for instability versus non-instability diagnoses or in patients undergoing open versus arthroscopic anterior stabilization. All 11 patients unable to return to running at final follow-up had chronic lower-extremity diagnoses limiting their running ability. Young military athletes undergoing arthroscopic and open shoulder surgery have a high rate of early return to running. Approximately 60% of patients report the ability to run 1 mile at 3 months postoperatively, and three-quarters of patients do so at 4.5 months. Age, sex, military occupation, underlying diagnosis or type of surgery did not influence the rate of return to running after shoulder surgery. Level IV, therapeutic case series.

Dynamic Anterior Stabilization of the Shoulder: Onlay Biceps Transfer to the Anterior Glenoid Using the Double Double-Pulley Technique

The treatment of anterior glenohumeral instability includes several surgical options, ranging from soft tissue to bony procedures—open or arthroscopic. In arthroscopic dynamic anterior stabilization (DAS) of the shoulder, the long head of the biceps is transferred to the anterior glenoid through a subscapularis tendon split. The biceps may be fixed either in an inlay or in an onlay position. Inlay DAS theoretically increases anterior glenohumeral stability through 3 different effects: the hammock effect, sling effect, and the tensioning effect. Onlay DAS may additionally increase stability through a labroplasty effect, produced by the onlay positioning of the biceps on the anterior glenoid rim. The current technical note presents tips and tricks, and pearls and pitfalls, to reproducibly perform onlay DAS using all-suture anchors and the double double-pulley technique.

Arthroscopic Dynamic Anterior Stabilization Using Either Long Head of the Biceps or Conjoined Tendon Transfer for Anterior Shoulder Instability Results in a Similarly Low Recurrence Rate

To compare the clinical outcomes of arthroscopic dynamic anterior stabilization (DAS) between transferring the long head of the biceps (DAS-LHB) and the conjoined tendon (DAS-CT) for anterior shoulder instability with <15% glenoid bone loss. From January 2016 to May 2019, a total of 63 patients who underwent DAS for recurrent anterior shoulder dislocation with <15% glenoid bone loss were included, comprising 33 patients in DAS-LHB group and 30 patients in DAS-CT group. Clinical outcomes were assessed preoperatively and at a minimum 3-year follow-up, including patient-reported outcomes, range of motion, and return to sports (RTS). Postoperative recurrent instability (including dislocation, subluxation, and subjective instability with a positive apprehension test), revisions and complications also were recorded. No significant demographic characteristics difference was detected between the DAS-LHB (26.3 ± 7.9 years) and DAS-CT groups (26.0 ± 6.7 years). At the latest follow-up, there were no significant differences between the 2 groups in functional scores: Oxford Shoulder Instability Score (14.8 ± 2.8 vs 15.2 ± 3.6), Rowe score (95.9 ± 6.5 vs 93.2 ± 10.2), visual analog scale for pain (0.8 ± 1.2 vs 0.7 ± 1.7), and American Shoulder and Elbow Surgeons (95 ± 8.8 vs 95.2 ± 9.1) (all P > .218). No significant difference was detected between groups in the rates of RTS (90.1% vs 86.7%, P= .700) and RTS at previous level (78.7% vs 73.3%, P= .258), respectively. No recurrent dislocation occurred in either group. One patient felt occasional subluxation in the DAS-LHB group, and one was positive for the apprehension test in each group. One patient presented with postoperative shoulder stiffness and underwent a secondary arthroscopic debridement in the DAS-CT group. Comparable rates of recurrence, complication, return to sports, and subjective shoulder function were observed between DAS-LHB and DAS-CT groups. Level III, retrospective comparative therapeutic trial.

Paper 29: Return to Sport Testing vs Time-Based Clearance in Posterior Shoulder Instability

Objectives:Recurrent pain, instability and loss of function are challenging complications that can occur after arthroscopic treatment of posterior shoulder instability and SLAP tears in athletes. Many surgeons allow return to sport after a designated arbitrary postoperative time point. Recent evidence has demonstrated that a majority of athletes have residual strength and functional limitations at 6 months postoperatively – the time at which most time-based protocols allow full return to sport. Recent data has also been presented that patients undergoing arthroscopic Bankart repair who are required to meet objective return to sport testing criteria have a 4x lower rate of recurrent anterior instability than those who return based on time elapsed since surgery. Considering these findings, the purpose of this study is to investigate the use of a similar objective return to sport testing protocol on recurrence rates following arthroscopic surgery for posterior shoulder instability and SLAP tears. We hypothesized that patients who meet objective return to sport criteria would have a lower rate of reoperation and recurrence of symptoms compared to those who did not undergo the testing and were cleared to return based on time from surgery.Methods:Consecutive patients (Group 1) who underwent arthroscopic posterior shoulder stabilization surgery with or without SLAP repair by a single surgeon from 2016 to 2019, had a minimum of 1 year follow up, and completed functional and strength testing to evaluate readiness for return to sport were included in this retrospective case-controlled study. These patients were compared to a control group of historical consecutive cases (Group 2) from 2012-2016 who did not undergo return to sports testing and were cleared for sports after a minimum of 6 months following surgery. Failure was defined as recurrent symptoms of pain or instability requiring reoperation. Exclusion criteria were: patients undergoing isolated anterior stabilization procedures with or without concomitant SLAP tears, multidirectional instability, and open procedures. Chi-square, Fisher exact tests and two-tailed Students T-test were performed. Statistical significance was set at p<0.05.Results:There were 33 patients in Group 1 who underwent return to sport testing, and 91 patients in Group 2, the historical control. There were no differences between groups regarding sex (p=0.46), hand dominance (p=0.16), side affected (p= 0.69). The average age of Group 1 (20.8 +/- 4 yrs) was significantly younger than Group 2 (31.5 +/- 9.1 yrs, p< 0.00001). Patients who underwent return to sport criteria-based testing protocol had a rate of recurrent symptoms of pain or instability of 12.1% compared to 18.6% for those who did not (p= 0.43). Similarly, there were no reoperations for in Group 1, while three patients in group 2 (3.3%) underwent revision surgery for recurrent symptoms. This difference, however, did not reach statistical significance (p= 0.5633).Conclusions:In our cohort of young patients undergoing arthroscopic surgery for posterior shoulder instability, we detected no significant difference in reoperation rate and recurrence of symptoms between athletes who underwent objective return to sport testing and those who were released to sport on a time-based protocol. This may be related to an overall lower rate of reoperation in patients undergoing arthroscopic posterior stabilization or SLAP repairs in general compared to those undergoing arthroscopic anterior stabilization and differences in tolerance and presentation of recurrent posterior instability/SLAP tears versus anterior instability. It is possible that criteria-based return to sport testing prior to clearance to return to sport may be less critical for improving failure rates following arthroscopic posterior stabilization and SLAP repair than for anterior stabilization. Alternatively, given low reoperation rates overall, future studies investigating the role of return to sport testing after arthroscopic surgery for posterior shoulder instability and SLAP repairs may need to include more patients in order to detect differences related to the testing protocol. This study provides a basis upon which further studies, involving larger patient populations, may be conducted to elucidate any impact on functional scores and recurrence rates that may be associated with return-to-sport protocols based on functional testing rather than time since surgery.

Paper 70: "Distance to Dislocation" as a Predictor of Surgical Failure Following Primary Arthroscopic Anterior Labral Repair: Rethinking the Glenoid Track Concept

Objectives:Larger amounts of bipolar bone loss have a strong association with shoulder re-dislocation following arthroscopic labral repair. Development of the Glenoid Track (GT) concept has helped propose bone loss cut-offs for shoulders that should not be managed with arthroscopic labral repair alone. Recent literature has suggested the use of the glenoid track as a continuous variable rather than a binary “on-track/off-track” concept. The re-dislocation risk for “on-track” shoulders with smaller distances to dislocation (DTD), or “near-track” shoulders, has not been previously described. We hypothesized that decreasing DTD, or on-track lesions approaching an off-track lesion, would result in an increased risk of failure following arthroscopic Bankart repair alone.Methods:We performed a retrospective analysis of 197 patients who had undergone primary arthroscopic anterior labral repair between 2007 and 2019 with minimum 2-year follow-up. Glenoid bone loss using a perfect-circle method and Hills-Sachs (HS) interval, were measured from pre-operative MRIs. GT was calculated using previously described methods. Surgical failure was defined as a patient who re-dislocated their shoulder following surgery. DTD was calculated by subtracting the HS measurement from the GT calculation. Patients with “off-track” lesions (negative DTD), and those who had undergone a concomitant arthroscopic remplissage were excluded. We performed a logistical regression model to evaluate the relationship between surgical failure and DTD, glenoid bone loss, Hill-Sachs lesion size, number of anchors used, and patient age. We then created a risk estimator tool that calculates the risk of dislocation with DTD as a continuous variable.Results:Twenty-eight patients (14%) sustained recurrent shoulder dislocations following anterior shoulder labral repair. Average follow up was 7.8 years and there were no demographic differences between those with recurrence and those without (p>0.05). All patients had less than 25% glenoid bone loss (range 0-23%). Increased DTD (p < 0.0005) and glenoid bone loss (p < 0.0005) were independent predictors of surgical failure. After adjusting for glenoid bone loss and patient age, logistic regression modeling showed that for every 1mm decrease in DTD, there was an associated 13.6% increase in re-dislocation risk (p = 0.003). Patient age, Hill-Sachs length, participation in collision sports, and number of anchors used were not significantly associated with failure risk (p>0.05). A DTD <10mm had a 4.26 times greater odds of failure compared to those with DTD >10mm (OR 4.26; 95% CI 1.57-11.65; p = 0.005). The risk estimator tool developed using a logistic regression modeling demonstrated a 19% risk of failure for DTD 10mm, 26% risk for DTD 8mm, 36% risk for DTD 6mm, 49% risk for DTD 4mm, and 67% risk for DTD 2mm after adjusting for glenoid bone loss and patient age (Figure 1).Conclusions:The main finding of this study was that on-track lesions approaching off-track lesions, the so-called “near track” lesions, are associated with an exponentially increased risk of recurrent dislocation following primary arthroscopic anterior stabilization with labral repair alone. Furthermore, DTD values of <10mm were associated with the highest odds ratios for failure and were 4 times more likely to fail than for patients with DTD values >10mm. All of the patients included in this analysis had “on-track” shoulder lesions and <25% glenoid bone loss. Historically, these values have been identified as “cut-offs” used to identify patients who can be treated successfully with arthroscopic labral repair without a remplissage or other augmentation. DTD is a simple calculation for bipolar bone loss that can be used to predict risk of recurrent dislocation. Our results demonstrate potential pitfalls in making treatment decisions for bipolar bone loss using a binary “on-track, off-track” construct. Rather, the glenoid track concept applied as a continuum may be more useful for optimizing treatment.“On-track” shoulder lesions <10mm with diminishing DTD have a substantially higher risk of surgical failure with arthroscopic labral repair alone. As the DTD approaches 0mm (“off track lesion”), the risk of failure increases exponentially. When making treatment decisions for shoulder instability, bipolar bone loss should be viewed as a continuum rather than discreet “on-track, off-track” entities. For high-risk patients with a DTD approaching 0mm, additional augmentation with remplissage or open approaches should be considered.DTD can be used to estimate patient’s risk of recurrent dislocation following primary arthroscopic anterior labral repair for treatment of anterior shoulder instability. Application of this calculation would help surgeons decide the best surgical treatment for patients following anterior shoulder dislocation and can be particularly valuable for high risk patients. Understanding the association between lower DTD values and failure can also help inform the surgeon and patient regarding the risks and benefits of available treatment options.

Paper 11: Return to Sport Testing vs Time-Based Clearance in Posterior Shoulder Instability

Objectives:Recurrent pain, instability and loss of function is a challenging complication that can occur after arthroscopic treatment of posterior shoulder instability and SLAP tears in athletes. Many surgeons allow return to sport after a designated arbitrary postoperative time point. Recent evidence has demonstrated that a majority of athletes have residual strength and functional limitations at 6 months postoperatively – the time at which most time-based protocols allow full return to sport1. Recent data has also been presented that patients undergoing arthroscopic Bankart repair who are required to meet objective return to sport testing criteria have a 4x lower rate of recurrent anterior instability than those who return based on time elapsed since surgery2. Considering these findings, the purpose of this study is to investigate the use of a similar objective return to sport testing protocol on recurrence rates following arthroscopic surgery for posterior shoulder instability and SLAP tears. We hypothesized that patients who meet objective return to sport criteria would have a lower rate of reoperation and recurrence of symptoms compared to those who did not undergo the testing and were cleared to return based on time from surgery.Methods:Consecutive patients (Group 1) who underwent arthroscopic posterior shoulder stabilization surgery with or without SLAP repair by a single surgeon from 2016 to 2019, had a minimum of 1 year follow up, and completed functional and strength testing to evaluate readiness for return to sport were included in this retrospective case-controlled study. These patients were compared to a control group of historical consecutive cases (Group 2) from 2012-2016 who did not undergo return to sports testing and were cleared for sports after a minimum of 6 months following surgery. Failure was defined as recurrent symptoms of pain or instability requiring reoperation. Exclusion criteria were: patients undergoing isolated anterior stabilization procedures with or without concomitant SLAP tears, multidirectional instability, and open procedures. Chi-square, Fisher exact tests and two-tailed Students T-test were performed. Statistical significance was set at p<0.05.Results:There were 33 patients in Group 1 who underwent return to sport testing, and 90 patients in Group 2, the historical control. There were no differences between groups regarding sex (p=0.46), hand dominance (p=0.16), side affected (p= 0.69. The average age of Group 1 (20.8 +/- 4 yrs) was significantly younger than Group 2 (31.6 +/- 9.1 yrs, p< 0.00001). Patients who underwent return to sport criteria-based testing protocol had a rate of recurrent symptoms of pain or instability of 12.1% compared to 18.9% for those who did not (p= 0.43). Similarly, there were no reoperations for in Group 1, while three patients in group 2 (3.3%) underwent revision surgery for recurrent symptoms. This difference, however, did not reach statistical significance (p= 0.5633).Conclusions:In our cohort of young patients undergoing arthroscopic surgery for posterior shoulder instability, we detected no significant difference in reoperation rate and recurrence of symptoms between athletes who underwent objective return to sport testing and those who were released to sport on a time-based protocol. This may be related to an overall lower rate of reoperation in patients undergoing arthroscopic posterior stabilization or SLAP repairs in general compared to those undergoing arthroscopic anterior stabilization and differences in tolerance and presentation of recurrent posterior instability/SLAP tears versus anterior instability. It is possible that criteria-based return to sport testing prior to clearance to return to sport may be less critical for improving failure rates following arthroscopic posterior stabilization and SLAP repair than for anterior stabilization. Alternatively, given low reoperation rates overall, future studies investigating the role of return to sport testing after arthroscopic surgery for posterior shoulder instability and SLAP repairs may need to include more patients in order to detect differences related to the testing protocol. Objective functional testing may be a viable alternative to arbitrary, time-based criteria for returning to sport in patients who have undergone arthroscopic posterior shoulder stabilization and SLAP repairs.

Arthroscopic Biceps Transfer to the Glenoid With Bankart Repair Grants Satisfactory 2-Year Results for Recurrent Anteroinferior Glenohumeral Instability in Subcritical Bone Loss

To evaluate the short-term outcomes of the arthroscopic dynamic anterior stabilization (DAS), which is a transfer of the intra-articular portion of the long head biceps through the subscapularis split and fixation on the anterior glenoid, combined with a Bankart repair. A retrospective evaluation was performed of DAS and a minimum of 2-year follow-up. Inclusion criteria were the presence of anteroinferior instability, a positive apprehension test at 90° of abduction and external rotation, and subcritical glenoid bone loss (less than 20%). Exclusion criteria were severe (≥20%) glenoid bone loss, presence of biceps lesions or rupture (spontaneous or biceps tenotomy), pre-existing glenohumeral osteoarthritis, multidirectional or voluntary instability, previous arthroscopic stabilization procedure, and epilepsy. Outcomes included the Rowe score, range of motion (ROM), and recurrence. Twenty-three patients were treated with DAS and arthroscopic Bankart repair during the study period. One person was lost to follow-up, leaving 22 patients available at last follow-up. Those 22 patients had an average age of 31.9 ± 12.3 years (range, 18-68) and were evaluated at an average follow-up of 3.2 ± 0.7 years (range, 1.2-4.2). The Rowe score increased from 36.1 ± 16.2 (range, 10-70) preoperatively to 89.8 ± 20.1 (range, 30-100) postoperatively (P < .001) with almost all patients (90.9%) improving their score beyond the minimal clinically important difference of 9.7 points. Postoperatively, ROM was maintained. Three patients (13.6%) analyzed at final follow-up demonstrated recurrence, one was successfully treated conservatively, but two revised with a Latarjet. No postoperative Popeye deformity, biceps cramping, or other complication were reported. The DAS procedure may be an option for augmentation of a Bankart repair in patients with anterior shoulder instability and subcritical bone loss. ROM is maintained without evidence of postoperative Popeye deformity or biceps cramping. Level IV, retrospective study.

Evaluation of the subscapularis split created with passive rotation during arthroscopic dynamic anterior stabilization (DAS): A cadaveric study

IntroductionThe purpose of the present study was to analyze the ability to create a subscapularis split by passive rotation of the arm during dynamic anterior stabilization (DAS) and to analyze the new geometry of the long head of the biceps LHB. HypothesisThe hypothesis was that this passive simple technique can create subscapularis split without additional dissection giving rise to new position of LHB with a new stabilization function. Material and methodsA technique of subscapularis split using the LHB was used in 12 fresh-frozen human cadaveric shoulders. A subscapularis split was created by passive rotation of the arm after the LHB is shuttled into the joint during DAS. The length of the subscapularis split, post-DAS position and length of the LHB, and the angulation of the LHB relative to bicipital groove were measured after DAS and if this new geometry can give a new dynamic effect on subscapularis muscle. ResultsThe mean length of the subscapular split after maximal rotation was 20.4±6.0mm (range: 10–32mm). The mean elongation of the LHB was 0.6±1.4mm (range: −1 to +3mm). The final angle of the LHB relative to the bicipital groove was 45±5 degrees (range: 41 to 55 degrees). DiscussionThere is no need to create a distinct split prior to DAS. Additionally, DAS maintains the length-tension relationship of the LHB. The post-procedure medial angulation of the LHB relative to the bicipital groove may provide a lowering of the subscapularis, helping explain the anterior reinforcement of this technique. Level of evidenceBasic science study, cadaver study.

Revision Arthroscopic Bankart Repair in the Military

Objectives:There is no consensus on the optimal method of stabilization (arthroscopic or open) for revision anterior shoulder stabilization. The purpose of this study was to determine the success of revision arthroscopic stabilization at preventing further recurrence in active duty military patients.Methods:53 revision arthroscopic stabilizations were performed at our institution between 2005-2016 for recurrent anterior shoulder instability after an arthroscopic Bankart index procedure. Shoulders with glenoid bone loss >20% were excluded from the study. The primary outcome of interest was the ability to return to activity/duty without subsequent instability. Patients were followed for time to a subsequent instability event and repeat revision arthroscopic stabilization following return to duty/activity.Results:Patient age at revision surgery averaged 22.9 ± 4.3 years. Mean follow up was 6.1 years (range 0.4-12.9). 34 out of 53 patients (64%) returned to duty without recurrent instability following revision arthroscopic anterior stabilization. 19 patients (36%) experienced recurrent instability following return to duty after revision arthroscopic stabilization. Glenoid bone loss averaged 7.8% ± 8.0% in the successful group and 6.5 % ± 6.5% in the failure group (p=0.573). Durability of the index surgery was significantly longer in the successful group (38.1 ± 31.3 months vs. 20.5 ± 17.8 months, p=.029). There was no difference between groups in patient age or number of anchors used in the index or revision stabilization procedures.Conclusion:Revision arthroscopic stabilization of failed primary arthroscopic Bankart repair has a failure rate of 36% in a young active duty military population, which is substantially higher than primary arthroscopic Bankart repair in this population and higher than revision arthroscopic Bankart repair in other patient populations. The similar amounts of bone loss between groups indicates that bone loss is not the primary determinant of failure in revision arthroscopic stabilization.

Bipolar Bone Loss And Glenoid Bone Loss Alone are Both Associated with Failure After Arthroscopic Anterior Shoulder Stabilization

Objectives: Glenoid and humeral bone loss are both known risk factors for failure after anterior shoulder stabilization. Several models have previously been proposed to characterize bone loss and its association with recurrent instability. The purpose of this study was to determine the association of failure after arthroscopic anterior stabilization with three different models of shoulder instability. Methods: 128 individuals who underwent primary anterior shoulder stabilization between 2007-2015 were included in this study. Subjects were excluded on the basis of prior shoulder surgery, multidirectional instability, presence of connective tissue disorder, and concomitant rotator cuff pathology. Glenoid bone loss and Hill-Sachs lesion size were measured using previously reported methods. Cases were defined as individuals who sustained either a subluxation or dislocation event after the index procedure, while controls were defined as individuals who did not. The association between failure and three different models of instability were investigated. In the first model, a receiver-operating curve was constructed to determine the amount of glenoid bone loss alone that would best predict failure. In the second model, lesions were classified as on-track or off-track based on the glenoid track concept. In the third model, a distance-to-dislocation was determined based on the glenoid track concept. Combinations of glenoid bone loss and distance-to-dislocation were varied to determine the combination that was most closely associated with failure. T-test, chi-square, and Fisher exact testing was conducted to determine associations between categorical and continuous variables with failure. Results: There were 44 cases and 80 controls. There was no difference in age (p =.72) and sex (p= .69) between the two cohorts. Receiver-operator analysis of glenoid bone loss alone demonstrated that a threshold value of approximately 12% could best predict failure (AOC = 0.72). 21/25 (84%) of individuals with at least 12% bone loss failed surgery compared to 23/103 (22.3%) who had less than 12% bone loss (p &lt; .001). Using the glenoid track model, 4/4 (100%) of individuals with off-track lesions failed surgery compared to 40/124 (32%) with on-track lesions (p &lt; .001). Using a bipolar bone loss model, the combination thresholds of 9% glenoid bone loss and 11 mm distance-to-dislocation was associated with failure in 18/20 (90%) of subjects while 26/108 (24.1%) of subjects who did not meet this threshold failed surgery (p &lt; .001). Intra-rater reliability for glenoid bone loss (ICC = 0.79) and Hill-Sachs lesion size (ICC = 0.75) were excellent. Conclusion: In our study, a threshold value of 12% glenoid bone loss predicted failure following an arthroscopic Bankart repair and all off-track Hill-Sachs lesions failed as well. Further, when both glenoid bone loss and glenoid track were subcritical, the combined use of a bipolar bone loss model accurately predicted failure. This model may be particularly useful for lesions felt to be on the cusp but not beyond threshold values for critical glenoid bone loss and off-track Hill-Sachs defects.

Arthroscopic Surgical Stabilization of Glenohumeral Dislocations with Clavicular Graft and Remplissage.

Surgical repair of the unstable shoulder begins with reattachment of the detached capsulolabral complex. The degree of damage to the glenohumeral articulation can be variable and is often related to the degree of trauma, duration of dislocation, and the number of instability events. There have been many surgical procedures proposed for the treatment of shoulder instability in the athlete, ranging from soft-tissue repair to coracoid transfer or the addition of a bone graft. The arthroscope provides an opportunity to visualize and repair the injured structures, returning the shoulder to maximal range of motion and permitting functional improvement. Indications for arthroscopic anterior stabilization include a first-time dislocation, patients with apprehension following dislocation, and recurrent dislocation and subluxation prior to creating advanced bone loss. If there is advanced bone loss, an augmented repair or a procedure other than arthroscopic stabilization has been recommended. Mobilization of the anterior capsule and fixation to recreate the proper anterior tension will limit translation and potential recurrence of instability. The steps of the arthroscopic anterior stabilization include:Perform examination under anesthesia to identify the directions and degree of humeral translation relative to the glenoid.Position the patient with the shoulder 30° abducted and 20° flexed.Create proper portals, including a posterior viewing portal, dual anterior portals, and accessory portals for suture anchor placement.Perform a diagnostic arthroscopy to determine the damaged structures and how they relate to shoulder positions that may invite future dislocations.Perform capsule and labrum mobilization to permit anatomic relocation of the injured ligament.Place a series of suture anchors along the anterior and inferior glenoid margin.Utilize suture hooks to retrieve the sutures placed through the capsule to advance the capsule superiorly to the glenoid margin.Assess glenoid deficiency and place an autograft anterior to the damaged glenoid rim in selected cases.Tenodese the posterior capsule and infraspinatus to a large Hill-Sachs lesion on the posterosuperior aspect of the humeral head in selected cases.Repair additional labral structures superiorly and posteriorly if they contribute to glenohumeral instability. The anticipated outcome is a return to sport and high-demand activities. Bracing is available, but the internal repair is the most reliable technique to protect the glenohumeral articulation. Additional techniques can be implemented when added trauma has resulted in severe bone loss of the glenoid, humeral head, or anterior capsular structures. A return to high-risk activities can be anticipated in 4 to 7 months.

Arthroscopic anterior shoulder stabilisation in overhead sport athletes: 5-year follow-up.

Shoulder instability following traumatic glenohumeral dislocation is a common injury sustained by athletes particularly in contact and collision sports. Overhead contact sports such as gaelic football and hurling pose a unique hazard to the glenohumeral joint, increasing the risk of dislocation. To assess return to sport, level of play, recurrence and functional outcomes in gaelic football and hurling athletes in comparison with players of other sports. A retrospective cohort study was carried out from 2007 to 2016. Follow-up was conducted via telephone interview using the Western Ontario Shoulder Instability Index (WOSI) score used to assess functional outcomes as well as return to sport, level of return and recurrence. Ninety patients were included with follow-up which was obtained on 61 patients (68%) with a mean follow-up of 5.04years. 91.8% played sport at the time of injury, 55.4% of those (31 patients) played a gaelic sport with 44.6% (25 patients) playing other sports. 76.8% returned to their sport, 80.4% of these able to return at their pre-injury level. Recurrence occurred in 10 patients (16.4%). WOSI scores were not significantly different between groups (p = 0.77). No significance in recurrence between groups was noted (p = 0.78). Favourable outcomes can be expected for overhead contact sport athletes undergoing anterior arthroscopic stabilisation for recurrent instability. Players from these groups returned to sport sooner than those from other sports and no difference in recurrence was noted. The level at which they can expect to return to is favourable with most athletes reaching their pre-injury level.

Risk Factors for Recurrent Shoulder Instability after Arthroscopic Revision Anterior Stabilization

Risk Factors for Recurrent Shoulder Instability after Arthroscopic Revision Anterior Stabilization

Risk Factors for Failure of Arthroscopic Revision Anterior Shoulder Stabilization

Recurrent anterior instability following a failed Bankart repair in the shoulder represents a challenging clinical scenario. Few studies have examined the role of arthroscopic revision anterior stabilization as a treatment option in these cases. The purpose of this study was to evaluate the outcomes of arthroscopic revision anterior stabilization for patients with recurrent instability after a failed index procedure. Ninety-two patients underwent arthroscopic revision anterior stabilization after a failed index (open or arthroscopic) stabilization procedure. Sixty-five patients with a minimum of 2 years of follow-up were included in this study. The mean age at the time of revision surgery was 26 years (range, 15 to 57 years). The rate of recurrent instability and risk factors for failure were evaluated; the mean duration of follow-up was 4.7 years (range, 2 to 10.8 years). Glenoid and humeral bone loss were quantitatively assessed using preoperative T1-weighted magnetic resonance arthrograms to determine if the lesions were on-track or off-track. Twenty-seven (42%) of the patients experienced recurrent instability at a mean of 2.3 years after arthroscopic revision anterior stabilization. On multivariate analysis, the presence of an off-track lesion, an age of <22 years, and ligamentous laxity were independent predictors of recurrence (p = 0.022, 0.028, and 0.031, respectively). Among a cohort with these risk factors excluded, the failure rate was 19%. Arthroscopic revision anterior stabilization is associated with a high rate of recurrent instability, and patient selection is of critical importance in order to minimize recurrence. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Arthroscopic knotless anterior labral stabilization using labral tape and wide awake anaesthesia-short term results

BackgroundThe shoulder is the least constrained of all joints of the body and is more susceptible to injury including dislocation. The rate of recurrent instability following primary stabilization procedure at 10 years of follow-up ranged from 3.4 to 20%. There is a lack of evidence in the literature regarding use of labral tape and anchors for anterior stabilization despite the growing market for this product. We describe the outcomes of 67 patients who underwent knotless arthroscopic anterior stabilisation under awake anaesthesia using 1.5 mm LabralTape with 2.9 mm Pushlock anchors for primary anterior instability by a single surgeon.MethodsThis was a retrospective analysis of prospectively collected outcome data for adult patients undergoing anterior stabilisation for primary traumatic anterior shoulder instability between 2013 and 2016 at two centres. Patients with > 25% glenoid bone loss, engaging Hill Sach’s, and multidirectional instability were excluded. All cases underwent surgery using awake anaesthetic technique. The surgical technique and post-operative physiotherapy was standardized. Outcomes were measured at 6 months and 12 months.ResultsOf the 74 patients in our study, 7 were lost to follow up. Outcomes were measured using the Oxford Instability Shoulder Score (OISS) and clinical assessment including the range of motion. The OISS showed statistically significant improvement from a mean score and standard deviation (SD) of 24.72 ± 2.8 pre-surgery to 43.09 ± 3.5 after the procedure at 12 months with good to excellent outcomes in 66 cases (98.5%). The mean abduction was 134.2 ± 6.32 and external rotation was 72.55 ± 5.42 at 60–90 position at 12 months. We report no failures due to knot slippage or anchor pull-out.ConclusionOur case series using the above technique has distinct advantages of combining a small non-absorbable implant with flat, braided, and high-strength polyethylene tape. This technique demonstrates superior medium term results to conventional suture knot techniques for labral stabilization thereby validating its use.

Risk Factors for Recurrent Shoulder Instability after Arthroscopic Revision Anterior Stabilization

Objectives:Individuals that fail arthroscopic anterior stabilization of the shoulder represent a unique and challenging patient population. To date, there have been few large studies that have investigated failure rates following arthroscopic revision anterior stabilization (ARAS) for failed primary arthroscopic stabilization. This study aims to determine the risk factors for recurrence of shoulder instability following ARAS. We hypothesized that male gender, younger age, participation in contact sports, significant glenoid and/or humeral bone loss, ligamentous laxity, and worker’s compensation would increase the risk of revision failure.Methods:Patients who underwent ARAS after a failed arthroscopic primary Bankart repair and had a minimum of 2-year follow-up were included in this study. Glenoid and humeral bone loss were quantitatively assessed using pre-operative T1-weighted magnetic resonance arthrograms to determine if the lesions were on- or off-track. Failure was defined as a recurrent dislocation or subluxation. Chi-square test and t-test were used to compare demographical and surgical parameters between failure and non-failure groups. The significance level was set to 0.05.Results:Sixty-five patients [age at revision = 26 years (range, 15 - 57), 44 (68%) male] met the inclusion criteria. The mean follow-up time was 4.7 years (range, 2 - 10.8). Twenty-seven patients (42%) had a failed revision at a mean time of 2.3 years (range, 0.2 - 6.1). Age less than 22 years old, ligamentous laxity, the presence of an off-track lesion, and a concomitant superior labral anterior to posterior were significantly associated with revision failure (p < 0.05) (Table 1). No difference was observed in the size of glenoid defect between failure and non-failure groups (14.1% ± 4.4% vs. 13.7% ± 3.9%, p = 0.762). The width and depth of the Hill-Sachs lesions were not significantly different between groups (width: 15.3 ± 5.1 mm vs. 14.2 ± 4.8 mm, p = 0.432; depth: 4.2 ± 2.3 mm vs. 3.5 ± 1.8 mm, p = 0.244). On multivariate analysis, only the presence of an off-track lesion, age less than 22 years, and ligamentous laxity were independent predictors for recurrent instability (OR = 8.9, p = 0.022; OR = 5.4, p = 0.028; OR = 7.8, p = 0.031, respectively).Conclusion:The failure rate of arthroscopic revision anterior stabilization was 42% with off-track lesions, age less than 22 years, and ligamentous laxity independent risk factors for recurrent instability. While ARAS may be a viable treatment option in the appropriate setting, our study suggests that considerable thought should be exercised before utilizing this approach given the significant number of patients who suffered recurrent instability at greater than 2-years follow-up. For young patients with off-track lesions and/or evidence of ligamentous laxity on physical exam, strong consideration should be given to either an open Bankart repair, a bony augmentation procedure such as a Bristow-Latarjet procedure, or an arthroscopic revision approach with additional augmentation such as a remplissage.Table 1.Parameters Tested Against Arthroscopic Revision Anterior Stabilization FailureaParameterRevision FailureNo Revision FailureORp-value Age at revision <22y 16/27 (59%)13/38 (34%)2.80 0.045 Ligamentous Laxity 10/27 (37%)5/38(13%)3.88 0.024 Off-Track Lesion 10/22 (45%)4/36(11%)6.67 0.003 SLAP Tear 11/27 (41%)6/38 (16%)3.67 0.024 Male Gender17/27 (63%)27/38 (71%)0.690.492BMI> 30 kg/m2 3/24 (13%)3/27 (11%)1.141.000Dominant Side Instability20/27 (74%)23/38 (61%)1.860.255Bilateral Anterior Instability3/27(11%)7/38 (18%)0.550.503Workers’ Compensation3/27 (11%)9/38 (24%)0.400.331Athletes12/27 (44%)17/38 (45%)0.990.981Contact sports9/12 (75%)12/17(71%)1.251.000Competitive Level3/12 (25%)3/17 (18%)1.560.699Open Primary Bankart Repair2/23 (9%)4/35(11%)0.741.000Traumatic Repair Failure7/18 (39%)16/35(46%)0.760.635Time from Failure to Revision < 1 y21/27 (78%)31/38(82%)0.790.706Total Number of Anchors ≤ 36/20 (30%)10/30(33%)0.860.804Number of Anteroinfaior Anchors ≤ 314/20(70%)19/30(63%)1.350.626Label Tear > 120°13/20(65%)20/30(67%)0.930.903 aData expressed as count/number of available cases (%). Competitive level is defined as collegiate or higher. Bold denotes significance. SLAP, superior labrum anterior and posterior; BMI, body mass index; OR, odds ratio.