With the increased rate of UCL reconstruction over the last decade [4], efforts to reduce injuries have been made, particularly at the level of youth baseball. Efforts to reduce injury in young pitchers have primarily focused on reducing pitch quantity, as the amount of pitching has been shown to correlate with the risk of subsequent elbow injury [44, 45]. Additionally, injuries are more likely to occur in baseball pitchers who express symptoms of fatigue or overuse. Fatigue has been shown to alter pitching kinematics, potentially setting the stage for future injury [46]. Based on these findings, pitch count recommendations for youth baseball players have been made at the national level as well as local and regional levels. Despite these efforts, a lack of knowledge and compliance with pitch count recommendations has been noted, with both youth baseball players and coaches deficient in this area, suggesting that further education on this topic is necessary [47, 48]. Further hindering compliance is the fact that players frequently play in multiple leagues with multiple coaches, which has also been shown to be a risk factor for injury, likely serving as a surrogate for overall pitch volume [45]. While pitch choice has often been implicated as a risk factor for elbow injury in youth pitchers, there is little solid evidence to support that throwing curveballs or sliders increases the risk of injury, although it may increase the incidence of arm pain [45, 49]. However, increased pitch velocity has been associated with an increased risk of elbow injury [44]. In light of these findings, several recommendations have been made to reduce the risk of elbow injury in youth pitchers and include responding to fatigue and pain with rest, avoid pitching more than 100 innings in a calendar year, encourage non-pitching activities for at least 4 months of the year, teach and reinforce proper mechanics, and encourage compliance with pitch count regulations [7, 49]. In order to address the increased rates of shoulder and elbow injuries in youth baseball pitchers, several organizations guided by expert panels, including Little League^® and USA Baseball, have provided age-specific pitch count and rest recommendations for young pitchers [50, 51] (Table 12.1). Additionally, optimizing shoulder and elbow health in the throwing athlete with a dedicated program focused on range of motion, core and lower extremity strengthening, and scapular stabilization can help correct kinematic abnormalities and prevent deficits, such as glenohumeral internal rotation deficits [52], which may reduce the risk of UCL injury.

Nonoperative management of UCL injuries remains the treatment of choice for non-throwing athletes. Nonoperative management in the non-throwing athlete includes rest for 4–6 weeks, activity modification, physical therapy, pain control with nonsteroidal anti-inflammatory medications, and possible hinged bracing as athletes return to play depending on their level of competition, sport, and position. Using this protocol, nonoperative management has even been shown to be effective in some throwing populations, including professional quarterbacks, where 90 % were able to return to sport without surgical intervention [53]. While the vast majority of the current literature has focused on failures of nonoperative management in baseball players, specifically pitchers, nonoperative management remains the treatment of choice for non-throwing and even some throwing athletes.

Nonoperative management of UCL injuries in baseball players have historically produced less than satisfying results. However, the literature frequently fails to distinguish between partial-thickness and full-thickness tears, limiting the applicability of findings. In one of the largest case series detailing the results of nonoperative treatment in the throwing athlete, Rettig et al. found that only 42 % of athletes were able to return to sport at a preinjury level [54]. The nonoperative protocol utilized in their study included two stages. The first stage consisted of complete rest from throwing for 2–3 months, pain control with anti-inflammatory medications, ice, and active and passive elbow range of motion with bracing at night. The second stage of the protocol was initiated after the athlete was pain free and included upper extremity strengthening, a progressive throwing program , and an elbow hyperextension brace. While their overall results would be considered poor, the inability to distinguish athletes with partial-thickness and full-thickness tears limits conclusions.

While nonoperative management of full-thickness tears is unlikely to produce satisfying results, nonoperative management of partial-thickness tears remains a viable option. Nonoperative protocols for partial-thickness UCL strains typically include a minimum of 3 months of no throwing activity, with immediate initiation of non-painful active and passive range of motion, progressing toward exercises to increase strength, power, and endurance while incorporating a thrower’s ten program [55]. A brace can be used during range of motion exercises to prevent valgus loading and restrict motion to a non-painful arc. Progression to throwing activities at 3 months only occurs if the athlete has non-painful and full range of motion and no increased valgus laxity on exam. With these requirements satisfied, the throwing athlete can initiate an interval throwing program while still focusing on the thrower’s ten program, core strengthening, and plyometric exercises [56]. If symptoms persist or reoccur at any point during the throwing program, surgical intervention can be considered.

In the era of biologic augmentation, the effectiveness of biologic agents in the treatment of patients with partial-thickness UCL injuries has been considered. One such biologic agent, platelet-rich plasma (PRP), has been extensively studied in the orthopedic literature with variable results depending on the pathology and anatomic site in question [57]. To date, a single study has evaluated the effectiveness of PRP in the treatment of partial-thickness UCL injury. In this study, Podesta and colleagues evaluated the effectiveness of PRP injections for throwers that had previously failed 2 months of nonoperative treatment, which included an interval throwing program. In their study, 88 % of athletes were able to return to throwing at an average of 12 weeks following PRP injection [58]. While these findings are promising, further studies specifically evaluating nonoperative management of partial-thickness injuries with or without biologic augmentation are necessary.

Surgical management of UCL injury is reserved for throwing athletes with full-thickness UCL tears who wish to return to competition or individuals with partial-thickness tears that have persistent medial elbow pain or valgus laxity following an appropriate nonoperative treatment course.

Prior to Jobe’s original description of UCL reconstruction [3], surgical intervention for UCL injury was limited to primary repair. While primary repair for acute avulsion injuries with suture anchor fixation or bone tunnels remains an option, the results for this technique are limited in the literature [59–61]. Early comparative studies revealed inferior results with repair as compared to reconstruction [2, 15], although those studies did not distinguish repair in acute injuries from repair in the more chronic setting where ligament attenuation is a known issue and reconstruction is preferable. In our experience, direct repair remains an option for acute proximal or distal avulsion injuries. Direct repair is particularly suitable for non-pitching athletes, such as baseball position players or non-throwing athletes that participate in football or wrestling. If repair is considered, it is important to carefully inspect the UCL at the time of surgery in order to rule out intrasubstance ligament injury or attenuation. If intrasubstance ligament injury or attenuation is noted, then a UCL reconstruction is performed. However, if the UCL injury appears to be a true avulsion injury, suture anchor methods have been described with good-to-excellent outcomes in young athletes [61].

The original UCL reconstruction as described by Jobe included a medial approach to the elbow with mobilization of the ulnar nerve for later transposition. Access to the UCL was gained by transecting the flexor–pronator mass off of the epicondyle, leaving a cuff of tendon attached to bone for later repair. With the flexor–pronator mass reflected distally, the UCL could be visualized from its origin at the medial epicondyle to its insertion on the sublime tubercle of the ulna. Tunnels were drilled at the sublime tubercle and medial epicondyle to allow passage of a palmaris autograft in a figure-of-eight fashion, which was then sutured again at its midpoint under appropriate tension. The mobilized ulnar nerve was then placed under the reflected flexor–pronator mass and the flexor–pronator mass repaired back to the cuff of tendon at medial epicondyle, resulting in a submuscular transposition of the ulnar nerve [3]. In the original series reported by Jobe et al. as well as the later comparative study by Conway et al. [2, 3], ulnar neuritis was a relatively common complication, contributing at least in part to low return to play numbers. In order to reduce this complication, the modified Jobe technique was described, which utilized a muscle splitting approach through the posterior aspect of the flexor–pronator mass in order to gain access to the underlying UCL [15, 62, 63]. Additionally, the humeral tunnels were oriented more anteriorly in order to prevent injury to the ulnar nerve [62]. While management of the ulnar nerve varied between authors, ranging from transposition with a flexor–pronator fascial sling to in situ decompression, the modified Jobe technique significantly reduced postoperative complications and allowed improved return to sport as compared to the original description [62].

In 2002, Rohrbough and colleagues described UCL reconstruction using the docking technique , which was the first major technique modification that addressed graft fixation, tensioning, and iatrogenic fracture concerns while also utilizing a flexor–pronator splitting approach [64]. Tunnels were created at the sublime tubercle and connected with a curette to maintain an approximately 1 cm bone bridge. A single dead-end humeral tunnel was made in the anterior portion of the medial epicondyle at the origin of the anterior band of the UCL, and two small holes were made with a dental drill or small burr to communicate with the humeral tunnel and allow suture passage. A palmaris or gracilis autograft was then passed through the ulnar tunnel and the sutured end of the graft pulled through one of the small communicating drill holes, effectively docking one limb of the graft. The free limb of the graft was then measured while maintaining the elbow in varus in order to estimate its length in the tunnel. A Krackow stitch was then placed in the remaining free limb of the graft and passed through the other small drill hole in the medial epicondyle to dock the free end in the humeral tunnel. With varus maintained at the elbow, the two free suture ends were tensioned and tied over the bone bridge at the medial epicondyle. Minor modification to the docking technique, including use of a doubled palmaris autograft, has also been described and referred to as the modified docking procedure [65]. The docking and modified docking technique provide greater control of graft tensioning while yielding equivalent or even improved biomechanical properties as compared to the Jobe technique [66–69].

More recent modifications to the Jobe and docking techniques have primarily focused on alternative or hybrid fixation at the ulna, humerus, or both. One popular modification is the eponymously named DANE TJ (David Altcheck, Neal ElAttrache, Tommy John) technique, which uses interference screw fixation at the UCL insertion on the ulna [70, 71]. As hypothesized by the authors, interference screw fixation better replicates the native anatomy of the UCL as it narrows at the ulnar footprint. Additionally, interference screw fixation eliminates the need for two bone tunnels, theoretically reducing the risk of iatrogenic fracture. Biomechanical comparisons of the different fixation techniques have been explored with variable results throughout the literature [66, 69, 72]. A clear limitation of these cadaveric biomechanical studies is that the in vivo dynamic stabilizers are rarely accounted for during testing and that healing is not considered, with each biomechanical study essentially serving as a time zero analysis of the construct strength.

As implant designs and fixation techniques continue to evolve, modifications to UCL reconstruction techniques will continue to be described. Suspensory and interference screw ulnar and humeral fixation using manufacturer-specific devices are frequently reported in the literature with little biomechanical superiority or inferiority noted with these subtle technique variations [73–76]. Similarly, a variety of graft choices have been described, including palmaris, gracilis, toe extensor, plantaris, and Achilles autograft as well as hamstring allograft [3, 77, 78], all of which have provided satisfying results in the literature when coupled with modern techniques. When carefully evaluating the literature, major technique advances since Jobe’s original technique description include the use of the flexor–pronator splitting approach as well as patient-specific management of the ulnar nerve depending on preoperative symptoms and intraoperative evaluation. In general, these advances have reduced postoperative complications and led to lower rates of revision surgery despite the increased rate of primary reconstructions being performed [6].

Patients are typically placed in a posterior splint for 1–2 weeks postoperatively with the elbow immobilized in 90° of flexion. Finger and wrist range of motion protocols vary while immobilized at the elbow, but with the flexor–pronator splitting approach, can typically be started as pain allows postoperatively as compared to the original Jobe description which took down the origin of the flexor–pronator mass [79]. After this short period of immobilization, patients are transitioned to a hinged elbow brace, with initial range of motion limited to 45–90° of motion, increasing range of motion by approximately 15° per week with the goal or reaching full passive range of motion by 6 weeks postoperatively. As elbow flexion contractures are common even in the throwing arm of uninjured athletes, gentle stretching exercises to reduce flexion contractures can be used but should be carefully guided by a patient’s symptoms. At 6 weeks postoperatively, the hinged elbow brace can be discontinued and light strengthening exercises can commence. In addition to the elbow, shoulder and wrist strengthening and range of motion should also be addressed. At 12 weeks postoperatively, more vigorous strengthening exercises can begin, and an organized throwing program, such as the thrower’s ten program [55], can begin at 14–16 weeks postoperatively. Progression through an organized throwing program should include careful monitoring of symptoms, including medial elbow pain. Throwing off a mound can be expected at 6–9 months postoperatively, with return to competition at 9–12 months in most throwing athlete s. For non-throwing athletes, postoperative protocols are less well defined but similarly should focus on obtaining full range of motion by 6 weeks with gradual strengthening beginning at this time as well. More aggressive strengthening can begin at 12 weeks postoperatively, with the goal of achieving normal strength and pain free range of motion prior to returning to sport.

Reporting of results for primary repair of UCL injuries is limited in the literature, and is primarily reserved for acute avulsion type injuries [34, 60] or in the setting of traumatic elbow dislocation with persistent instability [88]. Jobe and colleagues compared the results of primary UCL repair with their initial figure-of-eight reconstruction technique and found that 50 % of patients with direct repair returned to sport as opposed to 68 % of patients who had reconstruction. Results for repair were even less satisfying when evaluating professional baseball players as a subset [2]. Other comparative studies revealed similar results, with reconstruction providing superior results as compared to primary repair [15]. These early findings potentially set the stage for limited reporting of primary repair results. More recently, Richard and colleagues reported 90 % return to sport for collegiate athletes with acute UCL injuries. In their series, all three overhead athletes were able to return to sport [60]. Similarly, return to sport rates above 90 % have been reported for primary repair of acute, UCL injuries in patients younger than 22 years of age and in competitive female athletes [59, 61]. The more promising recent results for primary repair are likely secondary to improved indications, namely limiting repair to acute avulsion type injuries, whereas older studies likely included primary repair for more chronic injuries with attenuation of the ligament. In light of these findings and limited high level evidence, primary ligament repair may provide satisfactory surgical results in the appropriately indicated patient, although reconstruction remains the treatment of choice for the majority of throwing athlete s or those who fail nonoperative treatment.

UCL reconstruction is typically reserved for overhead athletes with full-thickness tears or athletes with partial-thickness tears that have failed a period of nonoperative treatment due to persistent medial elbow pain . Since Jobe’s original description [3], a variety of technique modifications have been made. Some of the technique changes altered the original approach, the so-called modified Jobe technique , which was performed through a flexor–pronator muscle-splitting approach [62], while others altered graft fixation at the sublime tubercle and medial epicondyle [64, 66, 70, 89]. Other changes to the original technique, including graft choice modifications, have also been described in the literature [65, 78]. With multiple technique descriptions, direct comparisons are limited. However, several general trends can be elucidated from the literature since the original technique descriptions.

Several recent systematic reviews have helped consolidate the results of the available Level 3 and 4 data with respect to UCL reconstruction [77, 80, 90]. The original outcomes reported by Jobe et al. noted a 62.5 % return to sport with nearly one-third of patients report ulnar nerve for at least some period of time postoperatively [3]. Over the next several decades, operative techniques were modified to improve upon these results. More recent studies have reported excellent results in over 90 % of patients with a return to sport rate of 90 % for docking and modified docking techniques [77, 80]. Additionally, while the most common complication postoperatively remained ulnar nerve neuritis or neuropraxia , the complication rate for this dropped to nearly 2 % for modern techniques using a muscle-splitting approach [80]. Other commonly reported complications included reconstruction failure, infection, tunnel fracture, and heterotopic ossification. Today, UCL reconstruction is most frequently performed through a muscle-splitting approach using either palmaris or gracilis autograft. While the aggregate numbers in the literature predominantly describe the modified Jobe technique, there has been a trend toward increased use of the docking or modified docking technique, which is the technique of choice for the senior author given its consistent ability to allow return to sport while avoiding significant complications.

While return to sport data has been consistently reported, other outcomes of interest have recently been investigated, particularly in high demand athletes, including collegiate and professional pitchers. Despite the optimistic return to sport results with new and improving techniques, there is some evidence to suggest that pitchers who underwent UCL reconstruction frequently return to the disabled list for ipsilateral throwing arm injuries with a decline in common pitching performance metrics compared to preinjury including earned run average, innings pitched, and average fastball velocity [84, 87]. Although less frequently reported, this information is important to convey to elite athletes as their goals often extend beyond simply returning to sport, but frequently include goals that allow them excel in a competitive environment.

Despite the recent increased incidence of UCL reconstructions, the rate of reconstructions requiring revision has decreased, possibly secondary to improved surgical technique and postoperative rehabilitation efforts [6]. However, when reconstructions do fail and revision reconstruction is required, the return to sport rate for professional baseball pitcher s is significantly lower than for primary reconstruction [91–93]. Additionally, complications are more frequently noted in revision surgery as compared to more recently described primary reconstruction techniques [93]. Revision reconstruction procedures pose several technical challenges, including difficulty with fixation depending on the location and mode of failure, as well as obvious limitations with graft choice depending on the primary surgical technique. Given these less than satisfactory results and notable technical challenges with revision reconstruction procedures, future efforts should aim to continue to improve upon primary reconstruction techniques in order to decrease the revision rate, while also aiming to improve upon revision reconstruction techniques and rehabilitation protocols given the increasing number of at risk patients with a history of UCL reconstruction.