Trends in Medial Ulnar Collateral Ligament Repair and Reconstruction From 2007 to 2016: A Population-Based Study of a Large Private Insurance Database

Abstract

Background: Ulnar collateral ligament (UCL) reconstruction and UCL repair of the elbow are commonly performed procedures, resulting in high return-to-play rates. Whether the incidence rate of UCL reconstruction vs UCL repair has changed over time is not currently known. Purpose/Questions: We sought to assess temporal trends in the incidence rates of UCL repair and UCL reconstruction and to identify factors associated with UCL reconstruction. We hypothesized that UCL repair would demonstrate an increased incidence overall in recent years with an associated decline in UCL reconstruction rates. Methods: Using the PearlDiver Research Program to query the Humana administrative claims database, we identified patients who had undergone UCL repair and/or reconstruction from 2007 to 2016. Patients were stratified by age (15–19; 20–29; 30–49 years), sex, and year (2007–2011 vs 2012–2016). Poisson regression analysis (continuous variables) was used to calculate the incidence risk ratio (IRR); chi-square tests were performed for categorical variables, and odds ratios were calculated with 95% confidence intervals (CI). Results: The incidence rate of UCL repair was greater in 2012–2016 than in 2007–2011 (IRR: 1.86, 95% CI: 1.16–2.96). The incidence rate of UCL reconstruction vs UCL repair was greater for patients aged 15 to 19 years (IRR: 3.37, 95% CI: 1.97–5.77) but not patients aged 20 to 29 years (IRR: 0.89, 95% CI: 0.49–1.59) as compared with patients aged 30 to 49. Males aged 19 years were more likely than females to undergo UCL reconstruction (IRR: 10.09, 95% CI: 1.37–3.45). Conclusion: While UCL procedures are becoming more popular, our retrospective analysis showed that young males are preferentially treated with UCL reconstruction, warranting further investigation into these trends.

Introduction

Ulnar collateral ligament (UCL) reconstruction and UCL repair of the elbow are commonly performed operations for throwing athletes, especially those who reach elite levels [1,8–11,16]. When conservative treatment measures fail, these injuries are often managed with UCL reconstruction [3,6,17]. However, most UCL surgeries are performed in collegiate players and younger athletes [5,20,21,27]. Reviews of national and statewide databases have demonstrated a rapid increase in the incidence of UCL reconstruction; this increase is most profound among adolescents and younger athletes [10,16].

The goals of UCL repair or UCL reconstruction include restoration of elbow stability, reduction of elbow pain, and a return to pre-injury functional levels [28]. Ulnar collateral ligament repair was not commonly performed in athletes until the last decade. Savoie et al [30] published a case series retrospectively evaluating young athletes (mean age: 17.2 years) who had excellent overall outcomes after UCL repair. In addition, in recent years, newer UCL repair techniques have been developed and promoted [4,7,32]. Thus, UCL repair is now advocated for certain patients, such as for younger athletes with proximal or distal avulsion UCL injuries [7,31,32]. In prior years, UCL reconstruction procedures would have been utilized preferentially for these athletes. [29].

The primary aims of this study were (1) to compare incidence rates of UCL repair and UCL reconstruction in 2 time periods: 2007 to 2011 vs 2012 to 2016; (2) to identify the rates of UCL repair vs UCL reconstruction in 3 age groups: 15 to 19, 20 to 29, and 30 to 49 years; and (3) to identify factors associated with UCL reconstruction. We hypothesized that UCL repair would demonstrate an increased incidence rate overall in recent years with an associated decline in UCL reconstruction incidence rates (Figure 1).

Fig. 1.

Incidence of UCL repair vs reconstruction procedures for patients aged 15 to 19. Years 2007-2016 assessed. UCL Ulnar collateral ligament.

Methods

A retrospective review of the Humana Inc. claims database was performed using the PearlDiver Research Program (PearlDiver Inc, Fort Wayne, IN) [25]. This database contains more than 25 million de-identified, HIPAA (Health Insurance Portability and Accountability Act) compliant records of U.S. patients, including Medicare beneficiaries and people covered by private insurance plans. Patients who underwent UCL repair and UCL reconstruction were identified retrospectively using current procedural terminology (CPT) codes for UCL repair (repair medial collateral ligament, elbow, with local tissue; CPT 24345) and UCL reconstruction (reconstruction of the medial collateral ligament elbow with tendon graft, including harvesting of graft; CPT 24346). Patients were stratified by age (15–19; 20–29; 30–49 years old) and sex (male vs female). Incidence rates of UCL repair and UCL reconstruction procedures, respectively, were assessed in 5-year increments (2007–2011 and 2012–2016).

We identified 217 patients who had undergone UCL reconstruction and 204 patients who had undergone UCL repair. We excluded patients who were younger than 15 years and older than 49 years, as well as those who underwent concomitant UCL reconstruction and repair. In total, 78 patients (UCL repair) and 158 patients (UCL reconstruction) were eligible for inclusion in the study.

We included hospital inpatient and hospital outpatient procedures as well as those that took place at ambulatory surgical centers. Incidence rates of UCL repair and UCL reconstruction were calculated, as previously described by Erickson et al [10]. Incidence rates (number of procedures performed/100,000 individuals) were calculated by dividing the number of UCL repair or UCL reconstruction procedures during each period by the population at risk in the database, defined as the reference population. Reference populations for 2007 to 2016 were provided by the Humana claims database to account for changes in the database population over time.

Descriptive and inferential techniques were used to provide demographic analysis. Poisson regression analysis was used to assess incidence risk ratios (IRR) across UCL repair and reconstruction procedures (continuous variables). Pearson chi-square test was used to assess categorical variables and to report odds ratios (ORs) using 95% confidence intervals (CI). Statistical analysis was performed using SAS 9.4 (SAS Institute, Cary, NC). Statistical significance was defined as a P value of < .05.

Results

From 2007 to 2016, a total of 78 patients underwent UCL repair and 158 patients underwent UCL reconstruction. Of these, 151 (85.2%) were male. The UCL repair and UCL reconstruction procedures, respectively, were most often performed at hospital outpatient facilities (40/78, 51.3%; 87/158, 55.1%) followed by ambulatory surgery centers (22/78, 28.2%; 84/158, 53.2%). A minority of both UCL repair and reconstruction procedures were performed in inpatient facilities.

From 2007 to 2016, the number of UCL repair procedures performed was greater compared with that of UCL reconstruction (Tables 1 and 2) (IRR: 1.86, 95% CI: 1.16–2.96, P < .01). From 2012 to 2016, the incidence of UCL repair procedures (1.75 procedures/100,000 individuals) was greater than the incidence of UCL repair procedures performed from 2007 to 2011 (0.94 procedures/100,000 individuals). Incidence rates for UCL repairs vs UCL reconstructions were compared from 2007 to 2016 by age group and sex (Tables 2 and 3).

Table 1.

Incidence of UCL repair vs UCL reconstruction 2007 to 2016.

UCL repairs							UCL reconstructions
Years	Repairs, n	Reference population	Incidence	IRR	95% CI	P value	Reconstructions, n	Reference population	Incidence	IRR	95% CI	P value
2007–2011	27	2,860,041	0.94	Reference group			70	2,860,041	2.45	Reference group
2012–2016	51	2,911,814	1.75	1.86	(1.16–2.96)	<.01*	88	2,911,814	3.02	1.23	(0.90–1.96)	.19

Incidence rates calculated as number of procedures per 100,000 individuals. UCL Ulnar collateral ligament, IRR incidence risk ratio, CI confidence interval.

^*Significant P value < .05.

Table 2.

Incidence rates of UCL repair vs reconstruction from 2007 to 2016 by age group.

UCL repairs							UCL reconstructions
Age groups	Repair, No. (%)	Reference population	Incidence	IRR	95% CI	P value	Reconstruction, No. (%)	Reference population	Incidence	IRR	95% CI	P value
15–19	19 (24.36%)	490,001	3.88	3.37	(1.97–5.77)	<.01*	80 (50.63%)	490,001	16.33	28.39	(17.71–45.5)	<.01*
20–29	15 (19.23%)	1,472,697	1.02	0.89	(0.49–1.59)	.67	56 (35.44%)	1,472,697	3.80	6.61	(4.04–10.83)	<.01*
30–49	44 (56.41%)	3,805,403	1.16	Reference group			22 (13.92%)	3,805,403	0.58	Reference group

Incidence rates calculated as number of procedures per 100,000 individuals. UCL Ulnar collateral ligament, IRR incidence risk ratio, CI confidence interval.

^*Significant P value < .05.

Table 3.

Factors associated with UCL reconstructions.

Variable	Odds ratio	95% CI	P value
Years 2012–2016	0.67	(0.38–1.17)	.15
Years 2007–2011	Reference group
Ages 15–19	8.4	(4.12–17.23)	<.01*
Ages 30–49	Reference group
Ages 20–29	7.46	(3.47–16.10)	<.01*
Ages 30–49	Reference group
Males	4.64	(2.34–9.2)	<.01*
Females	Reference group

Reference populations provided directly by the Humana Inc. claims database. UCL Ulnar collateral ligament, CI confidence interval.

^*Significant P value < .05.

For patients aged 15 to 19 years, the incidence of UCL reconstructions performed increased from 13.11 procedures/100,000 individuals (2007–2011) to 20.17 procedures/100,000 individuals (2012–2016). Males aged 15 to 19 years were more likely to undergo UCL reconstruction procedures vs females aged 15 to 19 years (IRR: 10.09, 95% CI: 6.10–16.69, P < .01). Factors associated with patients undergoing the UCL reconstruction procedure were assessed (Table 3).

Discussion

The purpose of this study was to determine the rates of UCL repair and UCL reconstruction procedures performed from 2007 to 2016 in a retrospective analysis of a large de-identified insurance database of more than 25 million private insurance and Medicare claims beneficiaries. Our results indicated that from 2007 to 2016, more UCL repairs were performed than UCL reconstructions. There was also a significant increase in the number of UCL repair procedures performed over time. As compared with UCL repairs, UCL reconstructions were preferentially performed in males aged 15 to 19 years, likely representing a cohort of adolescent and youth athletes.

As an alternative to the UCL reconstruction procedure, UCL repair may be gaining in popularity. In the present study, a greater number of UCL repair procedures were performed during the later study period years, 2012 to 2016, as compared with the earlier period of 2007 to 2011. In addition, our results suggest that females and individuals aged 30 to 49 years were more likely to undergo UCL repair than UCL reconstruction. Patient-specific demands and mechanism of injury may have influenced whether operative repair or reconstruction was employed in these patients [2,13,18,19]. Of those who underwent UCL repair, a greater number of procedures were performed in hospital inpatients in our analyses, especially among patients aged 30 to 49 years, suggesting a traumatic mechanism of injury was likely. In the setting of a proximal or distal avulsion, the high tissue quality often present in adolescents may offer advantages for UCL repair [30]. A quicker return to sports (RTS)—especially for those who do not anticipate pursuing higher level or professional athletics—may be afforded by the UCL repair procedure [9]. Therefore, an open and honest discussion about athletic goals may be necessary to avoid donor site morbidity and the longer recovery associated with UCL reconstruction. However, further clinical data supporting outcomes is warranted to ascertain whether more surgeons should be performing UCL repair. Savoie et al [30] and Erickson et al [9] recently demonstrated good outcomes and an 87% RTS following UCL repair in appropriately indicated patients. Furthermore, Savoie et al [30] demonstrated faster recovery times and lower donor site morbidity in UCL repair compared with UCL reconstruction. Our results suggest that UCL repair might not be performed in all cases when it might be appropriate. We postulate that the procedure may not be as widely adopted over UCL reconstruction due to a paucity of clinical evidence supporting outcomes and because the techniques that residents and fellows learned in training may influence their preferences as independently practicing orthopedic surgeons.

Furthermore, the current study demonstrated that males 15 to 19 years of age were more likely to undergo UCL reconstruction than UCL repair. Previous studies have indicated that the average age of patients undergoing UCL reconstruction is 22.1 years, assessing mainly sample populations with individuals aged 18 and above [3,24]. Erickson et al found that the incidence of UCL reconstruction from 2007 to 2011 among patients aged 15 to 19 was 22 ± 3.4 UCL per 100,000 individuals [10,23]. Previous studies have indicated that UCL reconstruction is performed predominantly in patients between 15 and 24 years old, with projections suggesting that the rate of UCL reconstruction among individuals in this age group will be 14.6 ± 2.3 from 2015 to 2025 [23]. Similarly, our results suggest an increasing trend of UCL reconstruction procedures performed in patients 15 to 19 years and 20 to 24 years of age, consistent with prior literature [10,23]. Males are typically more commonly involved in overhead throwing sports such as baseball [14]. In these athletes, UCL reconstruction is most commonly utilized to address UCL injury [26]. Hodgins et al observed that male patients were 11.8 times more likely to undergo UCL reconstruction than female patients, an association that has persisted over time [15,16,23]. Results from the present study demonstrated that males aged 15 to 19 years were more than 10 times more likely than females to undergo UCL reconstruction, likely representing adolescent athletes.

Importantly, many high school and collegiate athletes do not go on to professional play [24,27]. Yet, literature on UCL reconstruction and repair outcomes exist predominantly from studies of professional and adult athletes. Regarding RTS for high school and collegiate athletes after UCL reconstruction and repair, the literature is inconclusive [3]. Estimates for RTS after UCL reconstruction indicate a 74% to 100% recovery rate specifically in the adolescent patient population [23]. Particularly among youth athletes, UCL reconstruction may be preferentially performed over UCL repair due to patient and surgeon motivations to increase RTS after a UCL injury. Interestingly, there was a spike in UCL reconstruction procedures from 2011 to 2012, followed by a decrease. Campaigns by the American Association of Orthopaedic Surgeons (AAOS) and the American Orthopaedic Society for Sports Medicine (AOSSM) to reduce these injuries may also have affected the observed rates of UCL reconstruction procedures, inviting avenues for future inquiry regarding injury prevention strategies. We suggest that the observed trends toward increased UCL reconstruction procedures among adolescent and youth athletes may warrant further guidance from orthopedic surgeons. Age-specific training recommendations as well as a diversification of sports played by a single athlete in a given year may be employed to mitigate the risks of overuse injuries such as UCL injuries and to reduce risk factors for operative interventions [12,22].

The limitations of this study include the use of de-identified data from an insurance claims database and reliance on accurate coding and billing. Patients were active in the data set 3 months prior and 1 year after undergoing each procedure. The data set only includes a subset of the U.S. population and may not be representative of patients nationwide. Individual patient data that might have influenced treatment decisions—such as the level of athletic status, presurgical treatment, or stated desire for a surgical procedure—were not available. Indications for surgical procedure were also not accounted for in the database. In addition, a single surgeon may have conceivably performed a disproportionate amount of UCL repair or UCL reconstruction procedures, which may limit the external generalizability of these results from the private payor database and introduce selection bias into the study population. The database predominantly contains privately insured patients, who may undergo UCL reconstruction at a greater rate than those with public forms of insurance. The reference populations used to calculate incidence rates of UCL repair and UCL reconstruction changes on an annual basis and may have introduced subject bias into the results. The study also did not include patients below 15 years old or above 49 years old, and we are unable to report values with <11 participants as per Humana Inc. to ensure HIPAA compliance. Recent advances in UCL repair technique may not have been adapted as widely during the years assessed in the current study, which may have depressed the number of UCL repairs captured by the present study and underestimated UCL repair rates. Due to the overall low number of UCL repair and UCL reconstruction procedures performed from 2007 to 2016 and the increase in reference population numbers as compared with previous literature from Erickson et al [10], these results may also have been predisposed to a type II error.

In conclusion, the number of UCL repair procedures performed from 2012 to 2016 was greater than those performed from 2007 to 2011 in a retrospective analysis of a large private insurance database. Males aged 15 to 19 years more frequently underwent the UCL reconstruction procedure vs UCL repair as compared with females and individuals aged 30 to 49 years. While UCL repair procedures are becoming more popular, young males are still preferentially treated with UCL reconstruction, warranting further investigation into these trends.