Paper 18: A Prospective, Randomized Trial of the Modified Jobe vs. Modified Docking Techniques for Ulnar Collateral Ligament Reconstruction in the Elbow

OBJECTIVES: Overhead throwing athletes, notably pitchers, subject the elbow to tremendous valgus stress, and numerous studies have demonstrated an increasing incidence of ulnar collateral ligament of the elbow (UCL) injury. However, surgical reconstruction has transformed this injury from career-ending to career-interruptive. Two primary techniques exist for UCL reconstruction (UCLR): 1) the Modified Jobe and 2) the Modified Docking techniques. Prior biomechanical comparisons have reported equivalent ulnohumeral stability. Systematic reviews of clinical studies have suggested that the Docking technique may result in improved rates of return to play (RTP) and fewer complications, but these comparisons have been indirect and complicated by changes in technique. Our objective was to perform the first prospective, randomized comparison of UCLR utilizing the Modified Jobe or Modified Docking technique as measured by Kerlan-Jobe Orthopaedic Clinic (KJOC) score, Andrews-Timmerman score, and Conway-Jobe score. As secondary outcomes, we sought to compare pre- and postoperative imaging characteristics, required tourniquet times, rate of complications, and RTP data. We hypothesized that no difference exists between the two techniques with regard to any of the above outcomes. METHODS: This study was a single-surgeon, prospective, randomized trial comparing the Modified Jobe and Modified Docking techniques for primary UCLR. Patients were eligible if they had clinical and radiographic evidence of UCL injury and participated in overhead sports. Patients were excluded if they were not an overhead athlete, lacked clinical and radiographic evidence of a UCL tear, or had a history of previous elbow surgery. An a priori power analysis was performed utilizing historic data from both techniques to generate a sample size of 80 (40 in each group). All patients were randomized to one of the two techniques for UCLR using a standardized, contralateral gracilis autograft. All patients underwent the same postoperative rehabilitation protocol including throwing and batting progressions. Patient reported outcomes (PROs; KJOC score, Andrews-Timmerman score, and Conway-Jobe score) were obtained preoperatively and at 6 months, 1 year, 18 months, and 2 years postoperative. Pre- and post-operative imaging including both stress ultrasound (SUS) and magnetic resonance (MRI/MRA) were obtained. Additional information including demographics, intraoperative data, complications, and RTP data were collected. T-tests or Mann-Whitney U tests were used to calculate differences between continuous data. Chi-Square or Fisher’s Exact were used for categorical data. RESULTS: There were 40 patients (38M/2F) enrolled in the Jobe group and 40 patients (39M/1F) enrolled in the Docking group. Demographics including sex ratio, age, time between injury and surgery, and sport and level of play were similar between groups. Detailed patient demographic data is given in Table 1. Six patients in the Jobe group and eight patients in the Docking group underwent concomitant anterior subcutaneous UNT (p=0.769). Gracilis autograft harvest and closure required similar mean tourniquet time in both groups (28.7 minutes in Jobe group vs 28.3 minutes in Docking group; p=0.721). However, UCLR required significantly longer upper extremity tourniquet time in the Jobe group (101.0 minutes vs. 92.0 minutes; p=0.008). Preoperatively, patients reported similar levels of function via all PROs. Postoperatively at 6 months, 1 year and 18 months, both groups reported similar PROs. At two years, patients reported similar scores in terms of Andrews Timmerman and Conway Jobe scores, however the Docking group reported significantly higher mean KJOC scores (75.0 vs 85.0; p=0.025). Following surgery, both groups took a similar mean time to swing a bat, to begin tossing, and to begin a mound program. Of the patients that returned for two year follow up in clinic, 28/32 in the Jobe group returned to play at a mean of 13.4 months, compared to 27/27 in the Docking group who returned to play at 14.3 months (p=0.166). Detailed patient outcome data is given in Table 2. All grafts were intact and showed progressive healing on MR and SUS at final radiographic follow-up. There were no significant differences in the rate of complications. One patient in the Docking group required reoperation with revision ulnar nerve decompression with transposition for persistent ulnar nerve symptoms. No patient in the Jobe group required reoperation. CONCLUSIONS: This study is the first and only prospective, randomized trial evaluating the outcomes of the Modified Jobe and Modified Docking techniques for UCLR. The study identified high rates of good-to-excellent results with equivalent RTP rates and time to RTP for both techniques. Surgeons should continue to utilize the technique with which they are most comfortable, but the Docking technique demonstrated reduced tourniquet times and superior KJOC scores at 2 years.