Reverse total shoulder arthroplasty for the treatment of proximal humeral fractures: patterns of use among newly trained orthopedic surgeons

J Shoulder Elbow Surg (2014) -, 1-5

www.elsevier.com/locate/ymse

Reverse total shoulder arthroplasty for the treatment of proximal humeral fractures: patterns of use among newly trained orthopedic surgeons Daniel C. Acevedo, MDa,*, Tobias Mann, MD, MSb, Joseph A. Abboud, MDc, Charles Getz, MDc, Judith F. Baumhauer, MD, MPHb, Ilya Voloshin, MDb a

Kaiser Permanente, Panorama City, CA, USA Department of Orthopaedics and Rehabilitation, University of Rochester, Rochester, NY, USA c The Rothman Institute at Thomas Jefferson University, Philadelphia, PA, USA b

Background: This study compared the use of reverse and hemishoulder arthroplasty for the treatment of proximal humeral fractures among orthopedic surgeons taking part II of the American Board of Orthopaedic Surgery board examination. We hypothesized that the use of reverse shoulder arthroplasty for fractures in the elderly is increasing amongst newly trained orthopedic surgeons. Materials and methods: We queried the American Board of Orthopaedic Surgery database for the cases of proximal humeral fractures treated with arthroplasty submitted between 2005 and 2012. We evaluated the prosthesis used, patient-specific factors, complications, and the difference in use by shoulder fellowshiptrained surgeons. Results: From 2005 to 2012, 5395 board-eligible orthopedic surgeons submitted cases to the database. Of these, 435 (mean, 54 per year) were proximal humeral fractures treated with arthroplasty. The overall incidence of reverse shoulder arthroplasty for fracture increased from 2% to 4% during 2005 to 2007 to 38% in 2012. Shoulder surgeons treated 5 times more proximal humeral fractures with shoulder arthroplasty and were also more than 20 times more likely to use a reverse implant (P < .0001). The difference in complication rates between reverse and hemishoulder arthroplasty was not significant (P ¼ .49). Patients who received a hemiarthroplasty tended to be younger (mean age, 70.8 vs 75.7 years; P ¼ .0015). Conclusions: Overall, the use of a hemiarthroplasty for fracture is still more common (62% in 2012), although the relative proportion of reverse implants is rising. Among shoulder surgeons, more than 50% of the arthroplasties performed for fractures during the past 3 years (2010-2012) have been reverse arthroplasties. Level of evidence: Epidemiology Study, Database Analysis. Ó 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Keywords: Reverse shoulder arthroplasty; proximal humeral fracture; shoulder trauma

Investigational Review Board approval was not needed for this report. *Reprint requests: Daniel C. Acevedo, MD, 13652 Cantara St, Panorama City, CA 91402, USA. E-mail address: [email protected] (D.C. Acevedo).

Proximal humeral fractures (PHFxs) are the third most common fracture in patients aged older than 65 years.2 Although most PHFxs in this population can be treated nonoperatively, there is a role for surgical intervention. Treating PHFxs in the elderly with open reduction and

1058-2746/$ - see front matter Ó 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. http://dx.doi.org/10.1016/j.jse.2014.01.005

2

D.C. Acevedo et al.

internal fixation or hemishoulder arthroplasty (HSA) is fraught with complications, including hardware impingement, tuberosity nonunion, malunion, and varying functional results.1,6,10,14,15,21 Since the 2004 introduction of the reverse shoulder arthroplasty (RSA) to the USA, the indications for this technique have expanded from cuff tear arthropathy to revisions for failed HSA, proximal humeral malunions, and acute PHFx in the elderly.19 RSA is an attractive possible option for complex 3- and 4-part PHFx in the elderly. Traditionally, HSA has been used in this patient population but has achieved varying functional results.1,17 HSA success depends on proper height, retroversion, and tuberosity healing, making this operation technically demanding even for the most experienced shoulder surgeons.3 The potential for poor outcomes when treating PHFxs with HSA has prompted interest in RSA as a means to gain pain relief and improved functional outcomes. RSA affords the deltoid a better mechanical advantage for elevating the arm by moving the center of rotation of the shoulder more medial and inferior. This implant can achieve adequate function in the absence of a competent rotator cuff and may offer more reliable results in the absence of tuberosity healing.5 A recent study that examined a nationwide database showed that there was a 2.5-fold increase in the use of shoulder arthroplasty in the USA from 1993 to 2008.12 The increase in shoulder arthroplasty in this study was speculated to be due to the rising use of RSA to serve a population of patients that was unmet before the release of this implant. One reason for this may be the use of RSA for PHFxs in the elderly. Arthroplasty for fracture is a complex procedure, and subspecialty training of the treating surgeon may have an effect on the type of procedure performed and on the rates of complications.7 It may be that newly trained surgeons are performing more RSAs for this indication. This study examined the prevalence of RSA as treatment for PHFx amongst orthopedic surgeons early on in their careers. Our hypothesis were that: 1. the use of RSA for PHFxs significantly increased after it was approved by the Food and Drug Administration in November 2004; 2. newly trained orthopedic surgeons would be more likely to use RSA than HSA when treating a PHFx; 3. the early complication rates for RSA and HSA reported by these surgeons would be higher than those reported in the literature; 4. surgeons with shoulder and elbow fellowship training would be more likely than their colleagues to perform RSA for a PHFx; 5. geographic region would have an effect on practice patterns; 6. patient gender would not appreciably affect choice of treatment; and 7. younger patients would be more likely than older patients to receive an HSA for a PHFx.

Materials and methods A research proposal was sent to the American Board of Orthopaedic Surgery (ABOS) to query the ABOS database for patients with PHFxs treated with RSA or HSA submitted by surgeons taking part II of the ABOS board examination between 2005 and 2012. The RSA was made available in the USA in November 2004, and thus, 2005 was chosen as the initial year for data collection. We requested information for all cases reported under the Current Procedural Terminology (CPT; American Medical Association, Chicago, IL USA) codes 23616 (shoulder arthroplasty for fracture), 23472 (total shoulder arthroplasty), and 23470 (hemiarthroplasty of the shoulder) performed for International Classification of Diseases Ninth Edition (ICD 9) codes 812.00 (closed proximal humeral fracture), 812.01 (surgical neck fracture), or 812.03 (anatomic neck facture). The CPT does not have a specific code for RSA; consequentially, these cases are submitted under the CPT code for total shoulder arthroplasty. A member at the ABOS also used the narrative description of cases to ensure that RSA was used. In addition, our assumption was that code 23472 in conjunction with fracture codes was an RSA because a conventional total shoulder arthroplasty in the setting of a fracture would be very rare. Data obtained from the ABOS database during the 8-year period, which were devoid of any patient- or surgeon-identifying data, included the fellowship training of the surgeon, procedure performed, diagnosis, patient age, sex, and reported complications. The resulting data set was divided into 2 groups according to whether or not the surgeon had completed fellowship training in shoulder surgery. These 2 groupsdshoulder and nonshoulder surgeonsdwere compared for type of prosthesis used (RSA vs HSA), complications, and trends of use over time. The Fisher exact test was used to compare the use of RSA for PHFx between surgeons who were and were not shoulder trained and to evaluate a possible relationship between the types of arthroplasty used and patient gender. The Student t test was used to determine if age influenced the type of arthroplasty implanted. A c2 test was performed to compare the rates of complications between surgeons by fellowship training.

Results From 2005 to 2012, 5395 board-eligible orthopedic surgeons submitted cases for the ABOS part II board examination. During this 8-year period, 173 fellowship-trained shoulder surgeons took the examination. There were 435 cases involving the treatment of a PHFx with HSA or RSA (mean, 54 cases per year), of which 69 were RSA and 366 were HSA. Shoulder-trained surgeons performed 28 RSAs and 35 HSAs, and nonshoulder-trained surgeons performed 41 RSAs and 331 HSAs. Of the 69 patients who received RSA, 11 were male and 58 were female. In the HSA group, 76 were male and 290 were female. The mean age was 75.7  8 years for those who received RSA and 70.8  12 years for those who received HSA. No gender difference between patients treated with HSA vs RSA was

ABOS RSA patterns among new surgeons found; however, patients who received HSA tended to be younger (mean age, 70.8 vs 75.7 years; P ¼ .0015). The overall incidence of RSA for PHFx increased from 1 to 2 per year (2%-4%) during 2005 to 2007 to 34 (38%) in 2012. Shoulder surgeons treated 63 of the 435 PHFxs (28 RSAs and 35 HSAs). Amongst shoulder surgeons, the use of RSA for PHFx increased from 0 (0%) in 2005 to 9 (75%) in 2011 and to 13 (65%) in 2012. During the entire study period, each shoulder surgeon treated 5 times more PHFxs with shoulder arthroplasty than did nonshoulder surgeons and were also more than 20 times more likely to use RSA (P < .0001; Fig. 1 and Fig. 2). A total of 17 complications were documented in the RSA group and 70 complications in the HSA group (Table I). The difference in complication rates between HSA (19.1%) and RSA (24.6%) was not statistically significant (P ¼ .49). The complication rates for shoulder-trained surgeons were 11.4% for the HSA group and 17.9% for the RSA group and for the other surgeons were 20% for the HSA and 29.3% for the RSA groups. The complication rates differed between the 2 groups, but our sample size was not large enough to confirm that these differences were significant. Nerve injuries, nonunion, and delayed union tended to be more common in the HSA group, whereas dislocations, hemorrhage, pulmonary embolism, and renal failure tended to occur more frequently in the RSA group. The number of patients in this study was insufficient to determine if the geographic region of the surgeons’ practices affected the type of arthroplasty used.

Discussion The use of shoulder arthroplasty in the USA has been on the rise, particularly from 1993 to 2008.12 The increase in use has been postulated to be due to the ability of RSA to treat shoulder problems that previously had poor or no solutions. Surgically indicated PHFxs in the elderly continue to be a difficult problem to treat. For those patients in whom an arthroplasty is indicated, HSA may have a variable result, and there may be a growing trend to use RSA to treat elderly patients with complex 3-part and 4part PHFxs.4,5,8,13,16,18,20 This study confirmed our hypothesis that the use of RSA has risen amongst newly trained surgeons, from 2% to 38% during the previous 8 years. Although more RSAs are being performed for PHFxs, most of these fractures in our study population were still being treated with HSA. The use of RSA in 2005 was substantially lower than in later years, which could have been partly due to availability and familiarity with the prosthesis. The increase that we see in our study may not reflect the current trends on a national level, and that there is an even larger rise amongst surgeons in practice is possible. The proportion of fellowship trained shoulder surgeons in our study was relatively small (173 of 5395). However,

3

Figure 1 The rates of reverse total shoulder arthroplasty (RTSA) and hemishoulder arthroplasty (HAS) for proximal humeral fractures per individual surgeon are shown. During the past 8 years, the relative proportion of RTSA has been increasing. The number of board-eligible surgeons taking the examination each year is also shown.

Figure 2 The rates of reverse total shoulder arthroplasty (RTSA) and hemishoulder arthroplasty (HAS) for proximal humeral fractures per individual shoulder surgeon are shown. Since 2010, shoulder surgeons are performing more RTSAs for proximal humeral fractures than HSAs. The number of board-eligible shoulder surgeons taking the examination each year is also shown.

they performed 28 of the 69 RSA cases, making shoulder surgeons 20 times more likely to use RSA for a PHFx than nonshoulder surgeons (P < .0001). This may be due to experience gained in a shoulder fellowship that uses this particular implant. We had no information on the type of practice of the surgeons in this study, and it is possible that shoulder specialists were referred more complex fractures, which may have mandated RSA over HSA. Our hypothesis that newly trained orthopedic surgeons would be more likely to use RSA than HSA when treating a PHFx was incorrect, and the use of the gold standard HSA is still a more common treatment for complex PHFxs. RSA is a technically demanding procedure that offers its own unique set of complications.7,22 Our study was unable to show a difference in the complication rates between HSA and RSA when used for PHFxs (19.1% vs 24.6; P ¼ .46). The low rate of complications seen with RSA was surprising. A recent systematic review showed that the average complication rate was 44% across all indications, with a

4

D.C. Acevedo et al. Table I The total number of complications reported according to the type of shoulder prosthesis Complication

Number of complications for HSA

Surgical unspecified Medical unspecified Infection Nerve palsy or injury Dislocation Nonunion or delayed union Bone fracture Implant failure Patient died Wound dehiscence Anesthetic complication Surgical procedure intervention Renal failure Pulmonary embolism Pneumonia Hemorrhage Total

RSA

13 9 7 7 6 5 5 4 3 2 2 2

1 5 1 0 2 0 1 1 1 0 0 1

2 1 1 1 70

1 1 1 1 17

HSA, hemishoulder arthroplasty; RSA, reverse shoulder arthroplasty.

36% complication rate when RSA was used for acute fractures.23 In addition, RSA has an early learning curve of 40 cases, with a trend toward higher complications during the learning period.11 Furthermore, instability after RSA is the most common complication across studies, with a mean incidence of 4.7%23; however, the instability rate in our study was only 2.9% and was not the most common complication in the group. Our third hypothesis was incorrect: newly trained surgeons using RSA for PHFxs did not have a higher complication rate (24.6%) compared with previous reports.23 Of the 17 complications in the RSA group, 12 were medically related, indicating that this implant may have been use for patients with more comorbidities. It is possible that younger surgeons have been trained in the use of this implant and its surgical technique, leading to lower complication rates. The ABOS database has a limited capability of capturing long-term complications because data are only gathered for a 6-month period. Long-term complications were not evaluated in this study, and the rates may actually be higher than reported with more follow-up. Interestingly, the rate of reported complications amongst shoulder fellowship-trained surgeons was lower for the HSA (11.4% vs 20%) and RSA (17.9% vs 29.3%) groups. Although we were unable to determine significance, shoulder fellowshiptrained surgeons may have more experience treating these difficult problems from their fellowships, which may translate into a lower complication rate. These rates may even out amongst all surgeons as years of practice increase.

There is no evidence in the literature comparing the rate of complications for RSA based on fellowship training of the surgeons. Long-term survivorship for this relatively new implant has been approximately 91% at 10 years and was previously recommended for patients aged older than 70 years.9 Our study was unable to show a significant association between age and the type of prosthesis used; however, patients who received RSA were older (mean age, 75.7 years). The current literature examining patients who have had an RSA reports a patient population with a similar average age.23 The surgeons in this group likely had stringent indications for RSA during their ABOS collection period and attempted to reserve RSA for a more elderly patient. Our study had some limitations. This was a retrospective study during a defined period of time in a surgeon’s career. The data obtained only show us the reported rates of RSA and HSA for this particular population of surgeons and not the trend across the nation. The low complication rate reported for this study was very short-term, and the patients in this study may have more complications arising with longer follow-up. We had no access to the radiographs of these cases, and there are also radiographic complications specific to an RSA, such as scapular notching, that may have been overlooked by surgeons early on in their career, thus artificially lowering the reported complication rate. Another limitation that bears mention is that because we did not have access to radiographs in this study, we were unable to evaluate the characteristics of the fractures. This is important, because more complex PHFxs that are not amenable to fixation are often referred to surgeons with fellowship training in shoulder surgery. In addition, more complex fractures may have been thought to be more suitable for RSA than for HSA and, therefore, were sent to fellowship-trained surgeons as well. These factors may have inflated the proportion of RSAs for PHFxs performed by shoulder fellowship-trained surgeons. Lastly, surgeons tend to be more conservative in their treatments during their board collection period, and this study may not reflect the use of RSA for PHFxs in their general practice.

Conclusions Our data show that it is becoming increasingly common for board-eligible orthopedic surgeons to use RSA in the treatment of PHFxs. Although the use of HSA for PHFxs is still more common (62% in 2012), the use of RSA for PHFxs is rising. Among shoulder surgeons, more than half of the arthroplasties performed for PHFxs during the past 3 years have been RSA. The difference in complication rates between the HSA and RSA groups was not statistically significant. However, more complications in the RSA group, such as renal failure and

ABOS RSA patterns among new surgeons pulmonary embolism, seem unrelated to the implant and could potentially be explained by the fact that the patients in the RSA group were on average older.

References 1. Antu~ na SA, Sperling JW, Cofield RH. Shoulder hemiarthroplasty for acute fractures of the proximal humerus: a minimum five-year followup. J Shoulder Elbow Surg 2008;17:202-9. http://dx.doi.org/10.1016/j. jse.2007.06.025 2. Baron JA, Karagas M, Barrett J, Kniffin W, Malenka D, Mayor M, et al. Basic epidemiology of fractures of the upper and lower limb among Americans over 65 years of age. Epidemiology 1996;7:612-8. 3. Boileau P, Krishnan SG, Tinsi L, Walch G, Coste JS, Mole D. Tuberosity malposition and migration: reasons for poor outcomes after hemiarthroplasty for displaced fractures of the proximal humerus. J Shoulder Elbow Surg 2002;11:401-12. http://dx.doi.org/10.1067/mse. 2002.124527 4. Boyle MJ, Youn SM, Frampton CM, Ball CM. Functional outcomes of reverse shoulder arthroplasty compared with hemiarthroplasty for acute proximal humeral fractures. J Shoulder Elbow Surg 2013;22:327. http://dx.doi.org/10.1016/j.jse.2012.03.006 5. Bufquin TH, Hubert L, Massin P. Reverse shoulder arthroplasty for the treatment of three- and four-part fractures of the proximal humerus in the elderly: a prospective review of 43 cases with a short-term followup. J Bone Joint Surg Br 2007;89:516-20. http://dx.doi.org/10.1302/ 0301-620X.89B4.18435 6. Cai M, Tao K, Yang C, Li S. Internal fixation versus shoulder hemiarthroplasty for displaced 4-part proximal humeral fractures in elderly patients. Orthopedics 2012;35:e1340-6. http://dx.doi.org/10.3928/ 01477447-20120822-19 7. Cheung E, Willis M, Walker M, Clark R, Frankle MA. Complications of reverse total shoulder arthroplasty. J Am Acad Orthop Surg 2012; 19:439-49. http://dx.doi.org/10.4103/0973-6042.114225 8. Garrigues GE, Johnston P, Pepe MD, Tucker BS, Ramsey ML, Austin LS. Hemiarthroplasty versus reverse total shoulder arthroplasty for acute proximal humerus fractures in elderly patients. Orthopedics 2012;35:e703-8. http://dx.doi.org/10.3928/01477447-20120426-25 9. Guery J, Favard L, Sirveaux F, Oudet D, Mole D, Walch G. Reverse total shoulder arthroplasty: survivorship analysis of eighty replacements followed for five to ten years. J Bone Joint Surg Am 2006; 88:1742-7. http://dx.doi.org/10.2106/jbjs.e.00851

5 10. Jost B, Spross C, Grehn H, Gerber C. Locking plate fixation of fractures of the proximal humerus: analysis of complications, revision strategies and outcome. J Shoulder Elbow Surg 2012;22:542-9. http:// dx.doi.org/10.1016/j.jse.2012.06.008 11. Kempton LB, Ankerson E, Wiater JM. A Complication-based learning curve from 200 reverse shoulder arthroplasties. Clin Orthop Relat Res 2011;469:2496-504. http://dx.doi.org/10.1007/s11999-011-1811-4 12. Kim SH, Wise BL, Zhang Y, Szabo RM. Increasing incidence of shoulder arthrplasty in the United States. J Bone Joint Surg Am 2011; 93:2249-54. http://dx.doi.org/10.2106/JBJS.J.01994 13. Lenarz C, Shishani Y, McCrum C, Nowinski RJ, Edwards TB, Gobezie R. Is reverse shoulder arthroplasty appropriate for the treatment of fractures in the older patient? Early observations. Clin Orthop Relat Res 2011;469:3324-31. http://dx.doi.org/10.1007/s11999-0112055-z 14. Mighell MA, Kolm GP, Collinge CA, Frankle MA. Outcomes of hemiarthroplasty for fractures of the proximal humerus. J Shoulder Elbow Surg 2003;12:569-77. http://dx.doi.org/10.1016/S10582746(03)00213-1 15. Plausinis D, Kwon YW, Zuckerman JD. Complications of humeral head replacement for proximal humeral fractures. Instr Course Lect 2005;54:371-80. 16. Reitman RD, Kerzhner E. Reverse shoulder arthoplasty as treatment for comminuted proximal humeral fractures in elderly patients. Am J Orthop (Belle Mead NJ) 2011;40:458-61. 17. Robinson CM, Page RS, Hill RM, Sanders DL, Court-Brown CM, Wakefield AE. Primary hemiarthroplasty for treatment of proximal humeral fractures. J Bone Joint Surg Am 2003;85:1215-23. 18. Sirveaux F, Roche O, Mole D. Shoulder arthroplasty for acute proximal humerus fracture. Ortho Traumatol Surg Res 2010;96:683-94. http://dx.doi.org/10.1016/j.otsr.2010.07.001 19. Smith CD, Guyver P, Bunker TD. Indications for reverse shoulder replacement: a systematic review. J Bone Joint Surg Br 2012;94:57783. http://dx.doi.org/10.1302/0301-620X.94B5.27596 20. Valenti P, Katz D, Kilinc A, Elkholti K, Gasiunas V. Mid-term outcome of reverse shoulder prostheses in complex proximal humeral fractures. Acta Orthop Belg 2012;78:442-9. 21. Voos JE, Dines JS, Dines DM. Arthroplasty for fractures of the proximal part of the humerus. Instr Course Lect 2011;60:105-12. 22. Walch G, Bacle G, Ladermann A, Nove-Jodderand L, Smithers CJ. Do the indications, results, and complications of reverse shoulder arthroplasty change with surgeon’s experience? J Shoulder Elbow Surg 2012;21:1470-7. http://dx.doi.org/10.1016/j.jse.2011.11.010 23. Zumstein MA, Pinedo M, Old J, Boileau P. Problems, complications, reoperations, and revisions in reverse total shoulder arthroplasty: a systematic review. J Shoulder Elbow Surg 2011;20:146-57. http://dx. doi.org/10.1016/j.jse.2010.08.001