Evalua&ng the Na&ve Length-­‐Tension Rela&onship in Arthroscopic Suprapectoral Biceps Tenodesis: An MRI Assessment of Contralateral Shoulders John Prodromo, MD; Mary K. Mulcahey, MD; Raymond Hong, MD; Tal S. David, MD Methods: All pa&ents undergoing arthroscopic suprapectoral biceps tenodesis between January 2013 and May 2014 at one center were evaluated for inclusion in the study. Pa&ents undergoing concomitant rotator cuff repair, labral repair for instability, or with contralateral biceps tendon pathology were excluded. Addi&onal exclusion criteria included any pa&ent whose tenodesis was noted to have failed either clinically or on diagnos&c imaging at follow up. Pa&ents included in the study underwent a postopera&ve MRI of bilateral shoulders. The distance from the superior por&on of the humeral head to the LHB MTJ was measured bilaterally. One musculoskeletal-­‐trained radiologist made all MRI measurements using the same MR magnet. The measurements from each matched pair were compared using a paired t-­‐test to determine if arthroscopic suprapectoral biceps tenodesis anatomically restored the LHB length-­‐tension rela&onship. Distance (mm) Purpose: To evaluate the posi&on of the musculotendinous junc&on of the long head of the biceps (LHB) following arthroscopic suprapectoral biceps tenodesis and compare the posi&on to the nonopera&ve shoulder. Pa&ent number Pa8ent measurements from humeral head to biceps tendon musculotendinous junc8on MRI imaging demonstra8ng the opera8ve side tenodesis site at the musculotendinous junc8on (A-­‐D) and the nonopera8ve side with the tendon within the bicipital groove at the musculotendinous junc8on (E-­‐F). Results: A total of 17 pa&ents met the inclusion criteria. Fourteen of the seventeen pa&ents underwent a postopera&ve MRI of bilateral shoulders. The distance from the superior por&on of the humeral head to the LHB musculotendinous junc&on was significantly larger on the opera&ve side when compared to the nonsurgical side (opera&ve side mean 98.3mm, standard devia&on 13.4mm; nonsurgical mean 87.3mm, standard devia&on 9.1mm; mean difference 11.1mm; p=0.0105). Patient
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Mean:
SD
SEM
Operative Side
Distance(mm)
98.91
84.92
108.54
105.6
74.98
74.75
101.88
94.97
98.31
94.98
117.32
117.84
95.21
108.51
98.34
13.38
3.58
Contralateral Side
Difference (mm)
Distance(mm)
85.25
13.66
81.76
3.16
111.89
-3.35
88
17.6
84.86
-9.88
84.93
-10.18
74.75
27.13
84.87
10.1
84.8
13.51
91.56
3.42
94.61
22.71
78.14
39.7
81.13
14.08
95.05
13.46
87.26
9.09
2.43
Conclusion: The musculotendinous junc&on of the LHB in pa&ents who underwent arthroscopic suprapectoral biceps tenodesis was located more distal than the contralateral control, as measured on MRI.