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Editorial Commentary: Should We Worry About Progressive Glenoid Bone Loss After Arthroscopic Bankart Repair?
Editorial Commentary: Should We Worry About Progressive Glenoid Bone Loss After Arthroscopic Bankart Repair? Daniel J. Solomon, MD., Associate Editor
Abstract: One of the key factors in shoulder stabilization surgery is how much glenoid bone loss is present. Too much glenoid bone loss, or the combination of glenoid bone loss combined with a humeral side HilleSachs deformity, can lead to an “off-track” lesion and significantly greater risk of recurrence. If the potential surgical solution for instability leads to greater glenoid bone loss, we could create more problems for our patients.
See related article on page 44
G
lenoid bone erosion concerns us in patients with recurrent instability, but what if one of our most common solutions to instability potentially worsens the bone loss about which we are so worried? In “Progression of Erosive Changes of Glenoid Rim After Arthroscopic Bankart Repair,” Hirose, Nakagawa, Iuchi, Mae, and Hayashida found worsening glenoid bone loss on postoperative computed tomography (CT) scans after arthroscopic Bankart repair.1 Glenoid width commonly decreased by more than 5% compared with the preoperative measurement. They divided their cohort into normal glenoid (group N), glenoids with erosion (or preoperative glenoid bone loss) (group E), and bony Bankart injuries (group B). Overall, more than one half of the shoulders showed a decrease of glenoid width, but the number with stable or increased glenoid bone width was greater in group B. Hirose et al. found postoperative recurrence in 24 of 176 (13.6%) in patients followed more than 2 years postoperatively. Those patients whose glenoid width decreased compared with preoperative measurement had 15.5% recurrence. The recurrence rate found in their study is similar to that identified by Waterman et al.2 This group identified a failure rate of 13.8% with
The author reports the following potential conflicts of interest or sources of funding: other from Journal of Arthroscopy, other from Arthrex, and other from Integra, outside the submitted work. Full ICMJE author disclosure forms are available for this article online, as supplementary material. Ó 2019 by the Arthroscopy Association of North America 0749-8063/191260/$36.00 https://doi.org/10.1016/j.arthro.2019.10.014
54
a 5% revision rate in 3854 military patients undergoing Bankart repair.2 When should we really worry about bone loss? Hirose et al. noted only a slight increase in recurrence despite the increased glenoid bone loss. Typically, glenoid bone loss greater than 20% of the native glenoid width was defined as “critical.”3,4 Shin et al.5 suggest that a critical amount of glenoid bone loss that may result in recurrent glenohumeral instability after arthroscopic Bankart repair is 17.3% or more with respect to the longest anteroposterior glenoid width. The concept of “sub-critical” bone loss also has been explored, with some studies now suggesting as little as 13.5% loss of glenoid bone width as significant. Shaha et al.6 found an overall failure rate of 12.3% in their arthroscopic Bankart repairs. They noted when bone loss exceeded 13.5% of glenoid width, the Western Ontario Shoulder Instability Index score worsened, denoting a clinical failure, even if the patient did not experience a recurrent dislocation. The most notable concern from this study by Hirose et al. is that the bone loss increased, in some cases, leading to loss greater than 13.5%. This occurred in 18.2% of patients who preoperatively had a normal glenoid without any bone loss but in 35.7% of patients who had preexisting erosive changes to their glenoid. In a study of 50 college football players, Dickens et al.7 noted that return to sport after an arthroscopic Bankart repair in patients with greater than 13.5% glenoid bone loss risked recurrent instability. None of the 47 who had less than 13.5% bone loss experienced instability in at
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 36, No 1 (January), 2020: pp 54-55
55
EDITORIAL COMMENTARY
least 1 season of football after their surgery. These patients, who were at the United States Military Academy, continued to have stable shoulders even after a mean of 3.2 years of active-duty military service after graduation. The 3 patients who had bone loss greater than 13.5% all experienced recurrent instability. Could the progressive loss of glenoid bone convert an “on-track” HilleSachs to an “off-track” lesion? We know that off-track lesions are bad with regard to risk of recurrent instability.8 Specifically, Shaha et al.9 found better predictability of recurrence after arthroscopic Bankart repair using the “track” concept rather than evaluating glenoid bone loss alone. Retrospectively, with regard to recurrent instability after an arthroscopic Bankart repair, the positive predictive value of an off-track measurement was 75% compared with 44% for the predictive value of glenoid bone loss of >20%. Why did increased bone loss occur in most cases even without recurrent instability? Hirose et al. dive into this, suggesting the stress shielding of native glenoid or the particular arthroscopic Bankart technique used may have contributed to the loss effect seen on CT. The Discussion and Limitation sections of their study robustly describe details of this. The crux of the loss identified lies here. More research is needed. However, I believe the authors’ supposition that radiofrequency ablation of the far anterior articular surface, creating a trough for repair, may be the issue. Interesting, for those patients who had more than 1 postoperative CT, there was some recovery in glenoid width. This effect of regaining glenoid bone occurred most notably in patients with a bony Bankart preoperatively. This suggests that the initial effect of bone loss they found after Bankart repair may recover.
References 1. Hirose T, Nakagawa S, Iuchi R, Mae T, Hayashida K. Progression of erosive changes of glenoid rim after arthroscopic Bankart repair. Arthroscopy 2020;36:44-53. 2. Waterman BR, Burns TC, McCriskin B, Kilcoyne K, Cameron KL, Owens BD. Outcomes after Bankart repair in a military population: Predictors for surgical revision and long-term disability. Arthroscopy 2014;30: 172-177. 3. Itoi E, Lee SB, Berglund LJ, Berge LL, An KN. The effect of a glenoid defect on anteroinferior stability of the shoulder after Bankart repair: A cadaveric study. J Bone Joint Surg Am 2000;82:35-46. 4. Yamamoto N, Muraki T, Sperling JW, et al. Stabilizing mechanism in bone-grafting of a large glenoid defect. J Bone Joint Surg Am 2010;92:2059-2066. 5. Shin S-J, Kim RG, Jeon YS, Kwon TH. Critical value of anterior glenoid bone loss that leads to recurrent glenohumeral instability after arthroscopic Bankart repair. Am J Sports Med 2017;45:1975-1981. 6. Shaha JS, Cook JB, Song DJ, Rowles DJ, Bottoni CR, Shaha SH, Tokish JM. Redefining “critical” bone loss in shoulder instability: Functional outcomes worsen with “subcritical” bone loss. Am J Sports Med 2015;43: 1719-1725. 7. Dickens JF, Owens BD, Cameron KL, DeBerardino TM, Masini BD, Peck KY, Svoboda SJ. The effect of subcritical bone loss and exposure on recurrent instability after arthroscopic Bankart repair in intercollegiate American football. Am J Sports Med 2017;45:1769-1775. 8. Giacomo GD, Itoi E, Burkhart SS. Evolving concept of bipolar bone loss and the Hill-Sachs lesion: From “engaging/ non-engaging” lesion to “on-track/off-track” lesion. Arthroscopy 2014;30:90-98. 9. Shaha JS, Cook JB, Rowles DJ, Bottoni CR, Shaha SH, Tokish JM. Clinical validation of the glenoid track concept in anterior glenohumeral instability. J Bone Joint Surg 2016;98:1918-1923.
Abstract: One of the key factors in shoulder stabilization surgery is how much glenoid bone loss is present. Too much glenoid bone loss, or the combination of glenoid bone loss combined with a humeral side HilleSachs deformity, can lead to an “off-track” lesion and significantly greater risk of recurrence. If the potential surgical solution for instability leads to greater glenoid bone loss, we could create more problems for our patients.
See related article on page 44
G
lenoid bone erosion concerns us in patients with recurrent instability, but what if one of our most common solutions to instability potentially worsens the bone loss about which we are so worried? In “Progression of Erosive Changes of Glenoid Rim After Arthroscopic Bankart Repair,” Hirose, Nakagawa, Iuchi, Mae, and Hayashida found worsening glenoid bone loss on postoperative computed tomography (CT) scans after arthroscopic Bankart repair.1 Glenoid width commonly decreased by more than 5% compared with the preoperative measurement. They divided their cohort into normal glenoid (group N), glenoids with erosion (or preoperative glenoid bone loss) (group E), and bony Bankart injuries (group B). Overall, more than one half of the shoulders showed a decrease of glenoid width, but the number with stable or increased glenoid bone width was greater in group B. Hirose et al. found postoperative recurrence in 24 of 176 (13.6%) in patients followed more than 2 years postoperatively. Those patients whose glenoid width decreased compared with preoperative measurement had 15.5% recurrence. The recurrence rate found in their study is similar to that identified by Waterman et al.2 This group identified a failure rate of 13.8% with
The author reports the following potential conflicts of interest or sources of funding: other from Journal of Arthroscopy, other from Arthrex, and other from Integra, outside the submitted work. Full ICMJE author disclosure forms are available for this article online, as supplementary material. Ó 2019 by the Arthroscopy Association of North America 0749-8063/191260/$36.00 https://doi.org/10.1016/j.arthro.2019.10.014
54
a 5% revision rate in 3854 military patients undergoing Bankart repair.2 When should we really worry about bone loss? Hirose et al. noted only a slight increase in recurrence despite the increased glenoid bone loss. Typically, glenoid bone loss greater than 20% of the native glenoid width was defined as “critical.”3,4 Shin et al.5 suggest that a critical amount of glenoid bone loss that may result in recurrent glenohumeral instability after arthroscopic Bankart repair is 17.3% or more with respect to the longest anteroposterior glenoid width. The concept of “sub-critical” bone loss also has been explored, with some studies now suggesting as little as 13.5% loss of glenoid bone width as significant. Shaha et al.6 found an overall failure rate of 12.3% in their arthroscopic Bankart repairs. They noted when bone loss exceeded 13.5% of glenoid width, the Western Ontario Shoulder Instability Index score worsened, denoting a clinical failure, even if the patient did not experience a recurrent dislocation. The most notable concern from this study by Hirose et al. is that the bone loss increased, in some cases, leading to loss greater than 13.5%. This occurred in 18.2% of patients who preoperatively had a normal glenoid without any bone loss but in 35.7% of patients who had preexisting erosive changes to their glenoid. In a study of 50 college football players, Dickens et al.7 noted that return to sport after an arthroscopic Bankart repair in patients with greater than 13.5% glenoid bone loss risked recurrent instability. None of the 47 who had less than 13.5% bone loss experienced instability in at
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 36, No 1 (January), 2020: pp 54-55
55
EDITORIAL COMMENTARY
least 1 season of football after their surgery. These patients, who were at the United States Military Academy, continued to have stable shoulders even after a mean of 3.2 years of active-duty military service after graduation. The 3 patients who had bone loss greater than 13.5% all experienced recurrent instability. Could the progressive loss of glenoid bone convert an “on-track” HilleSachs to an “off-track” lesion? We know that off-track lesions are bad with regard to risk of recurrent instability.8 Specifically, Shaha et al.9 found better predictability of recurrence after arthroscopic Bankart repair using the “track” concept rather than evaluating glenoid bone loss alone. Retrospectively, with regard to recurrent instability after an arthroscopic Bankart repair, the positive predictive value of an off-track measurement was 75% compared with 44% for the predictive value of glenoid bone loss of >20%. Why did increased bone loss occur in most cases even without recurrent instability? Hirose et al. dive into this, suggesting the stress shielding of native glenoid or the particular arthroscopic Bankart technique used may have contributed to the loss effect seen on CT. The Discussion and Limitation sections of their study robustly describe details of this. The crux of the loss identified lies here. More research is needed. However, I believe the authors’ supposition that radiofrequency ablation of the far anterior articular surface, creating a trough for repair, may be the issue. Interesting, for those patients who had more than 1 postoperative CT, there was some recovery in glenoid width. This effect of regaining glenoid bone occurred most notably in patients with a bony Bankart preoperatively. This suggests that the initial effect of bone loss they found after Bankart repair may recover.
References 1. Hirose T, Nakagawa S, Iuchi R, Mae T, Hayashida K. Progression of erosive changes of glenoid rim after arthroscopic Bankart repair. Arthroscopy 2020;36:44-53. 2. Waterman BR, Burns TC, McCriskin B, Kilcoyne K, Cameron KL, Owens BD. Outcomes after Bankart repair in a military population: Predictors for surgical revision and long-term disability. Arthroscopy 2014;30: 172-177. 3. Itoi E, Lee SB, Berglund LJ, Berge LL, An KN. The effect of a glenoid defect on anteroinferior stability of the shoulder after Bankart repair: A cadaveric study. J Bone Joint Surg Am 2000;82:35-46. 4. Yamamoto N, Muraki T, Sperling JW, et al. Stabilizing mechanism in bone-grafting of a large glenoid defect. J Bone Joint Surg Am 2010;92:2059-2066. 5. Shin S-J, Kim RG, Jeon YS, Kwon TH. Critical value of anterior glenoid bone loss that leads to recurrent glenohumeral instability after arthroscopic Bankart repair. Am J Sports Med 2017;45:1975-1981. 6. Shaha JS, Cook JB, Song DJ, Rowles DJ, Bottoni CR, Shaha SH, Tokish JM. Redefining “critical” bone loss in shoulder instability: Functional outcomes worsen with “subcritical” bone loss. Am J Sports Med 2015;43: 1719-1725. 7. Dickens JF, Owens BD, Cameron KL, DeBerardino TM, Masini BD, Peck KY, Svoboda SJ. The effect of subcritical bone loss and exposure on recurrent instability after arthroscopic Bankart repair in intercollegiate American football. Am J Sports Med 2017;45:1769-1775. 8. Giacomo GD, Itoi E, Burkhart SS. Evolving concept of bipolar bone loss and the Hill-Sachs lesion: From “engaging/ non-engaging” lesion to “on-track/off-track” lesion. Arthroscopy 2014;30:90-98. 9. Shaha JS, Cook JB, Rowles DJ, Bottoni CR, Shaha SH, Tokish JM. Clinical validation of the glenoid track concept in anterior glenohumeral instability. J Bone Joint Surg 2016;98:1918-1923.