ABSTRACT
Purpose To evaluate small-size hamstring (HS) autografts for biomechanical properties and determine a threshold diameter necessary for appropriate reconstruction. Methods In a controlled laboratory setting, biomechanical testing was performed upon 15 hamstring autografts. The grafts were divided into three groups by diameter, with five grafts each at diameter sizes of 6, 7, and 8 mm. Testing of the specimens was performed using an MTS 858 (Materials Testing System, Eden Prairie, MN). We determined load to failure by looking at the maximum load as well as the stiffness of the graft. Statistical analysis was performed via analysis of variance (ANOVA) testing with Tukey's post-hoc test and P-values set at 0.05. Results There was a significant difference in ultimate tensile strength for the different size grafts: 1990 +/- 302.42 N for 6 mm grafts (n=5), 2179 +/- 685.36 N for the 7 mm grafts (n=5), and 3074 +/- 781 N for 8 mm grafts (n=5). This was statistically significant for the group overall (p=0.039), as well as between the 6 mm and 8 mm grafts (p=0.044). Graft stiffness for the 6 mm grafts was 317 +/- 85 N (n=5), 288.6 +/- 66 for 7 mm grafts (n=5), and 428.053 +/- 83 for 8 mm grafts (n=5). This achieved statistical significance for the group overall (p =0.037) as well as between the 8 mm and 7 mm grafts. Conclusions The biomechanical data presented here demonstrate that graft diameter is highly correlated with ultimate tensile strength and stiffness. Clinical relevance When viewing this biomechanical data in conjunction with prior clinical data, consideration should be given for the supplementation of an HS autograft as the size decreases below 8 mm.
ABSTRACT
Background Batter's shoulder has been defined as an acute posterior subluxation of the lead shoulder during a baseball swing causing a traumatic tear of the posterior labrum. There are limited data correlating repair techniques with return-to-play information but none utilizing standardized outcome measures. The purpose of this study is to examine a case series of patients for postoperative return-to-play and obtain follow-up using standardized outcome measures. Methods We retrospectively identified 10 patients with a batter's shoulder injury. Patients were included if they met the criteria for batter's shoulder injury. We attempted contact via telephone to complete Western Ontario Shoulder Instability (WOSI) and Disability of Arm Shoulder and Hand (QuickDASH) evaluations. We successfully reached five of the patients. The minimum follow-up was one year and the maximum was 11 years. Results All five patients in our cohort were able to return to play at the previous level without limitation. Patients reported a very low percentage limitation on the WOSI and QuickDASH questionnaires and results are detailed further on. Range of motion (ROM) and strength were not affected. Conclusion Batter's shoulder is an infrequent cause of posterior labral tearing, leading to a painful swing that can limit sports activity. In our limited series, all patients treated with arthroscopic repair were able to return to play at the previous level, confirming a significantly improved prognosis for a batter's shoulder injury in contrast to return to play after other causes of posterior labral tears.
