Injury to the elbow ulnar collateral ligament (UCL) from valgus forces was first described in a javelin thrower in 1946 by Waris.¹ The injury then became well recognized in overhead throwing athletes with baseball pitchers at highest risk. Jobe et al.² developed the original UCL reconstruction and described the technique with initial results in 1986. The technique utilized a tendinous transection and reflection of the flexor-pronator mass, submuscular transposition of the ulnar nerve, and creation of humeral tunnels that penetrated the posterior cortex (Fig. 30-1). This technique offered excellent exposure at the expense of morbidity to the flexor-pronator mass and ulnar nerve. Since that initial report, modifications in the surgical technique have been made to ease technical demands and decrease soft tissue morbidity. A muscle splitting approach has been developed to avoid detachment of the flexor-pronator mass with or without subcutaneous transposition of the ulnar nerve.³ Modifications in bone tunnel creation have also been made, which direct the tunnels anterior on the humeral epicondyle to avoid risk of ulnar nerve injury while the graft remains passed in a figure-eight fashion.³ Further changes in bone tunnel configuration have also been developed to reduce the number of tunnels and facilitate easier graft tensioning.^4,5 Results with these modified techniques have proven effective in returning high-level athletes back to throwing.

Patients with a diagnosis of UCL insufficiency that fail nonoperative treatment are candidates for reconstruction. Accurate diagnosis is based on a history of medial elbow pain during the late cocking/early acceleration phase of throwing. Chronic injuries present gradually, often with painful symptoms occurring only when throwing greater than 50% to 75% of maximal effort, accompanied with inaccurate ball placement. Acute injuries may present suddenly with a pop, sharp pain, and inability to continue throwing. Physical examination features that support the diagnosis include point tenderness elicited directly over the UCL or toward its insertion site at the sublime tubercle. Valgus instability is tested with the patient’s elbow flexed between 20 degrees and 30 degrees to unlock the olecranon from its fossa as valgus stress is applied. The milking maneuver is performed by either the patient or the examiner by pulling on the patient’s thumb to create valgus stress with the patient’s forearm supinated and elbow flexed beyond 90 degrees. The moving valgus stress test is a modification of the milking maneuver where valgus stress is applied while the elbow is moved through an arc of flexion and extension. For both tests, the subjective feeling of apprehension, instability, or localized pain to the UCL indicates UCL injury.

Imaging studies confirm the diagnosis. Valgus stress radiographs may be used to document excessive medial joint line opening, and an opening greater than 3 mm has been considered diagnostic of valgus instability.^2,3,6 Conventional magnetic resonance imaging (MRI) delineates the UCL and is capable of identifying thickening within the ligament or more obvious full thickness tears. MR arthrography enhanced with intra-articular gadolinium improves the diagnosis of partial undersurface tears.⁷

Patients who wish to continue throwing, have failed nonoperative treatment, have an accurate diagnosis, and are willing to participate in the lengthy rehabilitation are indicated for surgical reconstruction. Certain career and timing
situations may favor more immediate reconstruction without demonstrating failed nonoperative treatment. Relative contraindications include an inability to participate in lengthy rehabilitation and poor patient motivation.

Patients who present with valgus extension overload should also be thoroughly evaluated and considered for UCL reconstruction. In a report of professional baseball players who underwent olecranon debridement, 25% developed valgus instability and eventually required UCL reconstruction.⁸ This important observation suggests that both the olecranon and the UCL contribute to valgus stability. Therefore, olecranon resection may increase the demand placed on the UCL in resisting valgus forces during throwing. A recent biomechanical study demonstrated that increasing amounts of olecranon resection result in increased elbow valgus angulation.⁹ The authors of that study suggested that these kinematic alterations place the UCL at increased risk for injury. Ahmad et al. have demonstrated that UCL injury results in contact alterations in the posterior compartment that leads to osteophyte formation (Ahmad et al., AOSSM Annual Meeting, Orlando, Fla, 2003). Based on these clinical and basic science studies, we advocate careful evaluation of the UCL in patients presenting with valgus extension overload. Consideration should be given to UCL reconstruction in combination with posterior debridement in these patients who fail nonoperative treatment and have combined posteromedial impingement and UCL injury.