Abstract
Background:
Medial ulnar collateral ligament (UCL) injuries of the elbow affect overhead athletes with an increasing incidence over the past few decades. Growing evidence supports UCL repair as a treatment option in patients with low-grade UCL injuries or complete avulsion tears without chronic degenerative changes of the ligament. With this evolution in treatment options, accurate epidemiological data are needed to better understand and treat these injuries.
Purpose:
To investigate the trends of elbow UCL repair and reconstruction as it relates to the incidence of surgically managed UCL injury diagnoses from 2016 to 2022.
Study Design:
Descriptive epidemiology study; Level of evidence, 3.
Methods:
The Agency for Healthcare Research and Quality's Nationwide Ambulatory Surgical Sample database was examined from the period of 2016 to 2022. Patient demographics, diagnosis codes from the International Classification of Diseases, 10th Revision, Clinical Modification, and Current Procedural Terminology codes were collected, and descriptive statistics reported for those who underwent elbow UCL reconstruction versus repair. Survey-weighted Poisson regression, including covariates for age and sex, was used to report trends in UCL procedures from 2016 through 2022. A subgroup of patients 10 to 39 years old was analyzed to approximate the population of overhead athletes.
Results:
From 2016 to 2022, there was a relatively greater increase in volume of UCL repairs compared with reconstructions performed (129% vs 0%). Among the 10- to 39-year-old population, there was an increased incidence of outpatient visits coded with UCL injury diagnoses by 59% (age-adjusted incidence rate ratio [IRR], 1.60; 95% CI, 1.25-2.06; P < .001). There was an increased incidence of repair by 150% (age-adjusted IRR, 2.53; 95% CI, 2.11-3.03; P < .001) and a stable incidence of reconstruction (age-adjusted IRR, 0.97; 95% CI, 0.88-1.08; P = .63).
Conclusion:
Outpatient encounters for UCL injury and incidence of UCL repairs increased with a stable incidence of UCL reconstructions from 2016 to 2022. This may suggest UCL repair is becoming a more favorable treatment option for certain UCL injuries; however, further studies evaluating indications and outcomes of UCL repair versus reconstruction are warranted to guide management.
Injuries to the medial ulnar collateral ligament (UCL) of the elbow remain a problem affecting overhead athletes from the youth to professional level in the United States. The American Sports Medicine Institute described the increasing incidence of these injuries in baseball pitchers over the past 2 decades as an “epidemic.” 11 A recent study of collegiate baseball players reported a significant increase in sports-related injuries from 2016 to 2021 and that UCL injuries were the second most common injury reported with the highest proportion of surgical intervention and the longest return to sport time. 12 The incidence of UCL injury and surgery in adolescent overhead athletes has also increased, and previous studies have projected the incidence of reconstruction to reach 14.6 per 100,000 at risk individuals in 2025. 16
The UCL stabilizes the medial elbow by resisting valgus forces seen during the late cocking and early acceleration phases of the throwing motion, and injury is believed to occur most commonly through repetitive microtrauma and overall degenerative changes to the ligament. 26 Historically, UCL reconstruction, as originally described by Dr. Frank Jobe in 1974, has been the gold standard for surgical management in athletes seeking to return to play.15,24,26 Return to play at the same level as preinjury has been reported at rates between 80% and 97% with this procedure, but with a typical recovery time of 12 to 18 months.8,25
By comparison, there is an increasing number of younger overhead athletes presenting with acute injuries to the UCL including sprains, partial tears, or avulsions from either the ulnar or the humeral attachment sites.19,23 In these patients, UCL repair has re-emerged over the past few decades as an alternative surgical option to reconstruction since promising results were shown in a case series by Savoie in 2008.2,24,25 This technique involves repairing the existing ligament, frequently in combination with suture augmentation or an internal brace device.2,25-28 It has been substantiated by multiple biomechanical studies comparing modern repair techniques with reconstruction to show similar biomechanical properties with some cases even favoring suture-augmented repair over reconstruction.3,6,13,25-27 When compared with reconstruction, UCL repair has shown comparable clinical outcomes and return to play at the previous level at rates between 92% and 96% in athletes across many different sports. 25 In addition to excellent outcomes, patients undergoing UCL repair may require shorter recovery times in comparison with reconstruction groups. 5 Therefore, repair may be a more favorable surgical option in patients with partial tears or avulsions to the UCL given its promising biomechanical and clinical results paired with shorter recovery period.
An increasing incidence of UCL repairs between 2007 and 2016 was shown in a previous database study. 2 Since that time, many studies have supported the biomechanical stability and clinical outcomes of the UCL repair in the correctly indicated patient. A more recent study of a Texas patient database by Willenbring et al 29 reported increasing rates of UCL repair and reconstruction, but showing the rate of repair increasing relative to reconstruction, reaching 40% of total UCL procedures by 2019. Our goal was to provide an update on the rates of UCL repair and reconstruction being performed on a national level using a nationwide database patient sample. With this knowledge, the trend toward UCL repair over reconstruction for UCL injuries may be proven generalizable to the US population. We hypothesized that the rates of UCL repair and surgically managed UCL injuries would increase over the study period. With this knowledge, the trend toward UCL repair over reconstruction for UCL injuries may be proven generalizable to the US population.
Methods
Data Source
We examined the Agency for Healthcare Research and Quality's Nationwide Ambulatory Surgical Sample (NASS) database from 2016 to 2022. As part of the Healthcare Cost and Utilization Project (HCUP) family of hospital discharge databases, NASS provides a nationally representative estimate of discharges from hospital-owned outpatient departments and ambulatory surgical centers (ASCs). It does not include freestanding ASCs not owned by a hospital system. Variables recorded by NASS include patient demographics, diagnosis codes from the International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM), Current Procedural Terminology (CPT) codes, hospital census region, rural or urban location, and teaching status of hospital setting. 22 NASS uses a sampling strategy requiring complex survey design weights and strata to provide unbiased national estimates of procedures. 14
Sex and age (grouped in 5-year increments) denominator data were obtained from the US Census Bureau intercensus years in order to calculate population-based procedure rates. 22 These data were exempt from human participant review by our institution after being reviewed and declared public data.
Patient Selection
Patients were identified using ICD-10-CM diagnosis and CPT procedure codes. Each discharge summary is coded with up to 25 diagnosis and 15 procedure codes. We searched all these codes to identify patients aged 0 to 85+ undergoing elective UCL reconstruction or repair procedures for diagnosis of UCL or medial collateral ligament (MCL) injury of the elbow from 2016 through 2022.
We identified isolated repair of the MCL of the elbow with local tissue with CPT code 24345, as well as reconstruction of the MCL of the elbow with a tendon graft, including graft harvest, as CPT code 24346. To estimate the injury rate involving any medical encounter, we used ICD-10-CM diagnosis codes for MCL sprains: S53.441 (UCL sprain of right elbow), S53.442 (UCL sprain of left elbow), and S53.449 (UCL sprain of unspecified elbow).
We excluded patients with concurrent repair of the lateral collateral ligament (LCL) of the elbow using local tissue (CPT code 24343) or reconstruction of the LCL of the elbow using a tendon graft (CPT code 24343), as our focus was on patients with isolated UCL injuries. We also included a separate group for analysis that included any relevant fracture diagnosis codes (S52.0: fracture of upper end of ulna; S52.1: fracture of upper end of radius; S42.4: fracture of lower humerus; S49.1: physeal fracture of lower humerus) that were coded with a UCL repair or reconstruction procedure code. Because procedure rates among those between ages 10 and 39 were highest, and because we sought to focus on injuries more likely to be sports related, we further restricted the graphical presentation of the rates and trends to the age groups of 10 to 39 years. However, this inevitably includes patients with a variety of injury mechanisms rather than overhead sport–specific injuries.
Covariates
NASS includes variables for race, income quartile by patient zip code, and expected primary payer. We recorded race and ethnicity variables as White, Black, Hispanic, or Other (combining Asian ethnicity, Pacific Islander, Native American, or Other races). Median income for the zip code where the patient lived was a proxy for socioeconomic status, and this was grouped into quartiles, as it was coded by HCUP (income thresholds change in absolute values annually). The expected primary payer was grouped as Medicare, Medicaid, Commercial, and Other. We estimated patient comorbidities using previously published Quan enhanced version of the Charlson Comorbidity Index (CCI). 20 Variables describing hospital location as urban or rural, as well as teaching status, were included in NASS.
Statistical Analysis
Descriptive statistics are reported for those who underwent isolated UCL reconstruction versus repair. Survey-weighted Poisson regression including covariates for age (at 5-year increments) and sex were used to report trends in elective UCL procedures from 2016 through 2022. By incorporating the log of the annual population size (denominator) as an "offset," Poisson models provide procedure rates and volume, along with age-specific trends. We also performed relative incidence rate ratios (IRR
Results
A total of 7783 isolated UCL procedures were reported over the 7-year period. Overall, 78.9% of patients were male and 21.1% were female. A total of 4684 patients had race available, and among patients with race or ethnicity reported, 76.9% were White, 3.5% Black, 11.4% Hispanic, and 8.2% Other. When assessing patient comorbidities, 88.8% had a grouped Charlson Comorbidity Index of 0, 10.0% at an index of 1, and 1.2% at an index of 2. The most common primary payer for surgical procedures was commercial health insurance at 76.4%. These data are shown in Tables 1 and 2.
UCL Repairs, Reconstructions, and Total Surgeries Performed Over Study Period by Year and by Male and Female Sex a
UCL ulnar collateral ligament.
UCL Repairs, Reconstructions, and Total Surgeries Performed Over Study Period for Race, Primary Expected Payer, and Grouped Charlson Comorbidity Index for Patient Comorbidities a
UCL ulnar collateral ligament.
UCL repair or reconstruction when associated with one of the included fracture diagnosis codes accounted for 14.2% of the total number of UCL procedures reported over the study period. In 2016, UCL repair associated with fracture represented 33.8% of all repair procedures and reconstruction associated with fracture represented 2.4% of all reconstruction procedures. By 2022, UCL repair associated with fracture decreased to 26.1% of all repair procedures and reconstruction associated with fracture represented 4.6% of all reconstruction procedures.
Reconstruction was more common over the study period with 5312 reconstructions performed compared with 2470 repairs performed. Among the UCL repair group, 72% were male and 28% were female compared with 82% male and 18% female in the reconstruction group. When breaking down by age groups, the number of procedures in that group was not included in the final total if there were less than 10. The 15- to 19-year-old age group had the highest volume of surgical intervention making up 47.3% of the repairs and 52.3% of the reconstructions. The next highest volume came from the 20 to 24 age group with 15.1% of the repairs and 25.6% of the reconstructions. All other age groups accounted for <10% of the total repairs or reconstructions reported.
Breaking down surgical procedures by year, the number of UCL repairs in 2016 was 219 compared with 809 UCL reconstructions. By 2022, the number of UCL repairs was 501 compared with 810 reconstructions. This represents a 129% increase in volume of UCL repair and a 0% increase in volume of reconstruction from 2016 to 2022. The increase in UCL repair volume met statistical significance whereas the change in UCL reconstruction volume did not (P < .001 vs P > .99). A more detailed breakdown of UCL repair and reconstruction rates with demographic data are shown in Tables 1 to 3. Total number of outpatient visits related to UCL injury are shown in Figure 1.
UCL Repairs, Reconstructions, and Total Surgeries Performed Over the Study Period by Age Group a
UCL, ulnar collateral ligament. Age groups with <10 procedures were not included in the final total.

Total ulnar collateral ligament (UCL) surgical procedures by age group, 2016 versus 2022. Total number of surgical procedures (combined UCL repair and reconstruction) shown by patient age group. The light gray bar represents the number of procedures in 2016 compared with the dark gray bar representing the number recorded in 2022.
When assessing annual trends in the 10 to 39 age group, there was a significant 59% increase in incidence of outpatient visits coded with UCL injury diagnosis with an incidence of 0.78 per 1,000,000 (95% CI, 0.62-0.93) in 2016 up to 1.24 (95% CI, 1.05-1.43) in 2022 (P < .001) with an age-adjusted IRR of 1.60 (95% CI, 1.25-2.06; P < .001). There was also a significant 150% increase in the rate of UCL repair going from 1.25 (95% CI, 1.01-1.48) per 1,000,000 in 2016 up to 3.13 (95% CI, 2.83-3.43) per 1,000,000 in 2022 (P < .001) with an age-adjusted IRR of 2.53 (95% CI, 2.11-3.03; P < .001). There was no significant change in rate of UCL reconstruction from 5.7 (95% CI, 5.28-6.11) per 1,000,000 in 2016 to 5.49 (95% CI, 5.09-5.88) per 1,000,000 in 2022 (P = .97) with an age-adjusted IRR of 0.97 (95% CI, 0.88-1.08; P = .63). There was also a significantly higher rate of increase in direct comparison of repair versus reconstruction from 2016 to 2022 with an IRR of 2.60 (95% CI, 2.11-3.21; P < .001). These trends and the volumes of UCL reconstruction and repair by age group from 2016 to 2022 are depicted in Table 3, Table 4, and Figure 2.
Incidence Rates of UCL Repair, UCL Reconstruction, and Outpatient Clinical Visits Coded With UCL Injury by Year 2016 and 2022 for Comparison a
UCL, ulnar collateral ligament.

Annual trends in ulnar collateral ligament (UCL) repair, reconstruction, injury diagnosis, and fracture-related procedures among patients aged 10 to 39 years old. Overall annual trends for patients from 2016 to 2022 (shown along x-axis) are shown representing mutually exclusive groups including UCL repair, UCL reconstruction, outpatient visits with UCL sprain diagnosis code, and UCL surgical procedures with co-coded fracture diagnoses. These are shown in linear form in rate per 1,000,000 patients (left-sided axis). The annual volume (right-sided axis) of all UCL-related encounters is demonstrated in bar graph form with the proportional contribution of each mutually exclusive category (UCL repair, UCL reconstruction, UCL injury diagnosis, or fracture) shown in varying shades of gray.
Discussion
Over the study period, from 2016 to 2022, the incidence of outpatient UCL injury–related visits increased among the 10 to 39 age group with a 150% increase in the incidence of UCL repairs and a stable incidence of UCL reconstructions. While many prior studies have reported on the growing rates of UCL repair and reconstruction in overhead athletes over time,2,12,16,21,30 there is a paucity of updated literature reporting on the incidence of UCL injury diagnosis in this age group and how these relate to the trends in different types of UCL surgical treatment among the national population.
As UCL reconstruction has been the gold standard for many decades given inferior results with early repair techniques, many prior epidemiological studies have focused on UCL reconstruction rates. Hodgins et al 9 reported a 193% increase in volume and a tripled rate of UCL reconstructions being performed from 2002 to 2011 in a New York State database study. A similar database study done by Idowu et al 10 analyzed UCL reconstruction rates from 2003 to 2014 with respect to age and reported that 96.6% of reconstructions were performed in patients aged 11 to 25 years with nearly a 7-fold increased rate among the 11- to 15-year-olds and roughly a 3-fold increase in the 16- to 20-year-olds and the 21- to 25-year-olds from 2003 to 2014. Another study over the 2003 to 2014 time period of New York State data by Mahure et al 16 reported an overall 343% increase in incidence of UCL reconstruction with a disproportionate increase in the 15- to 19-year-old populations with a projected incidence of 14.6 per 100,000.
While earlier studies of UCL repair outcomes showed inferior results to UCL reconstruction, Savoie et al 24 described the use of a suture-augmented repair technique used in younger high school and college athletes and reported a 93% rate of return to the same or higher level of play at 6 months postoperatively in 2008.
Since the publication of this study and several more with similar techniques and outcomes, there is now strong consensus that UCL repair may be favorable over reconstruction when considering surgical treatment in patients with a persistently symptomatic UCL partial tear or complete avulsion. 7 A recent systematic review performed by Spears et al 25 reports on the 8 biomechanical studies comparing augmented UCL repair with UCL reconstruction performed between 2016 and 2023 with the conclusion that augmented UCL repair demonstrates biomechanically equivalent torsional stiffness and torque at failure with less gap formation when compared with UCL reconstruction. On their analysis of clinical outcomes for augmented repair, they report a return to previous level of play rate of between 88% and 100% with a mean time to return of between 3.8 and 7.4 months when using an internal brace augment. The overall combined complication rate among the studies included was 8.7% with a 5.3% rate of reoperation, most commonly due to ulnar nerve symptoms. 25
A separate systematic review by Nagy et al 17 compares UCL repair outcomes with that of UCL reconstruction, which showed significantly lower return to previous level of play at 80.5% and 82.3% for the modified Jobe and the docking techniques, respectively, compared with 93.2% for repair with internal brace. Additionally, the mean time to return to previous level of competition was significantly longer at 17.0 and 16.1 months for the modified Jobe and docking techniques, respectively, compared with 6.6 months for the repair with internal brace. While the data from both studies include a high proportion of baseball athletes, they also include athletes of various other sports including softball, gymnastics, wrestling, football, cheerleading, weightlifting, javelin, swimming, volleyball, golf, and horseback riding. Ultimately, conclusions based on the direct comparison of results between reconstruction and repair groups are limited due to the heterogeneity of the studies included and patient selection bias.
Following these promising results and the disproportionate growth of younger patients receiving surgical treatment for UCL injuries, Danilkowicz et al 4 reviewed a national private insurance database from 2007 to 2017 to show growth in UCL repair incidence from 0.016 to 0.49 per 100,000 between 2007 and 2014, but then a drop back down to 0.012 by 2017. A separate study comparing incidence of UCL repair and reconstruction from 2007 to 2016 demonstrated that UCL reconstruction still had a higher overall incidence than repair, and this was most notable in the 15- to 19-year-old age group where the reported incidence was 20.17 per 100,000. 2 A more recent Texas database study by Willenbring et al 29 reported the growth of UCL repair outpaced UCL reconstruction by 5.4% over a period from 2010 to 2019 and made up 40% of the total UCL surgeries performed by 2019. While it is difficult to directly compare our results with these studies given the difference in databases, our data from 2022 shows an incidence of repair of 3.13 per 1,000,000 in the 10- to 39-year-old age group and is done using a nationwide database to offer more generalizability of the results.
With the growing body of evidence to support UCL repair as a treatment option for athletes with UCL injury with the advantage of faster return to sport and reduced donor-site morbidity, this is likely to explain the relatively increasing volume of UCL repair compared with the historical gold standard of UCL reconstruction shown in our results. Our study also shows an increasing incidence of UCL injury–related outpatient visits at a similar rate to the increasing incidence of UCL repairs with a stable incidence of UCL reconstruction when comparing between 2016 and 2022 data. This trend may suggest that UCL injury rates are continuing to increase in the 10- to 39-year-old population and are more frequently being treated with UCL repair rather than reconstruction if they progress to surgical management. This disparity in incident growth rates between repair and reconstruction is likely related to the promising clinical and biomechanical data from the past decade in support of UCL repair with suture augmentation in athletes providing the advantage of faster return to sport and reduced donor-site morbidity, making surgery a more palatable option for athletes with symptomatic tears considering operative management.
Limitations
This study has several important limitations to consider. First, this study uses a database, NASS, which is dependent on accurate CPT and ICD-10 coding in generating data for analysis. Studies have shown that error rates for surgical coding may approach 40% to 50%,1,18 which is a major limitation of our study and other studies that utilize similar databases. As the NASS database only provides CPT and ICD-10 codes, efforts to improve accuracy in coding including multidisciplinary review and audits of medical record are not feasible. Inaccurate coding of either procedure or diagnosis could alter our results and may not truly represent the incidence of UCL injuries. Specifically, the UCL sprain diagnosis code was often used concurrently with a UCL repair or reconstruction procedure code, which inflated the incidence of UCL injury diagnosis when these codes were counted twice. Additionally, the total incidence of surgically treated UCL injuries with repair or reconstruction was greater than the total number of outpatient visits with UCL sprain diagnoses coded. This suggests that there was a proportion of UCL injuries that were managed surgically that may have never been coded with a UCL sprain diagnosis. Therefore, we chose to report on strictly outpatient clinical encounters coded with a UCL injury diagnosis code, as we felt this would best represent the growing trend of UCL injury–related care over the study period. While this may show a trend in UCL injury rate, it may not be an accurate estimate of the true incidence and was subject to variations in coding practices by surgeons over the study period. Second, there is not a statistical comparison between demographics of surgical groups to draw conclusions regarding significant differences. Third, the study period included the time surrounding the COVID-19 epidemic, which likely affected trends of elective surgical procedure rates during the 2020 and 2021 years; however, we felt that inclusion of the data through 2022 helped to show more accurate trends at our study's final time point. Fourth, our data set did not include procedures performed at ASCs not owned by a hospital. While this may exclude a portion of patients treated at independent ASCs, we still captured a large cohort of patients, which is likely generalizable to the national population. We also did not specifically stratify patients with or without flexor tendon injuries but recognize that these concomitant injuries may influence surgical decision-making in certain cases. Last, we included all patients with a diagnosis of UCL sprain, which may include a wide variety of traumatic mechanisms despite separation of those managed surgically with co-coded fracture diagnoses. Therefore, these data were not entirely specific to overhead athletes.
Conclusion
The incidence of encounters related to UCL injury significantly increased by 59% between 2016 and 2022 in this national database study. A significant 150% increase in the incidence of UCL repairs was observed with a stable incidence of UCL reconstruction over the study period. This may suggest that UCL repair is becoming a more favorable treatment option for UCL injuries; however, further studies including specific indications for UCL repair versus reconstruction with associated outcomes are warranted to guide management.
Footnotes
Final revision submitted November 24, 2025; accepted December 25, 2025.
One or more of the authors has declared the following potential conflict of interest or source of funding: P.N.C serves as an American Shoulder and Elbow Surgeons board member, is a paid consultant for Depuy and Exactech Inc, serves on the editorial board of the Journal of Shoulder and Elbow Surgery, receives IP royalties for Responsive Arthroscopy, serves in research support for Smith & Nephew, and owns stock in TitinKM Biomedical. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.
Ethical approval was not sought for the present study.
