Factors affecting supination strength after a distal biceps rupture.

HYPOTHESIS: This study quantified pain (visual analog pain scale [VAPS]), disability (Disabilities of the Arm, Shoulder and Hand [DASH]) and isometric supination torque at 3 forearm positions in a prospective cohort of biceps-deficient arms to assess the potential for functional return with nonoperative treatment. MATERIALS AND METHODS: Twenty-three men (50 ± 11 years) with complete unilateral distal biceps avulsion underwent isometric supination strength testing of both limbs at 60° of supination, 0° (neutral), and 60° of pronation. After exclusion of 1 outlier patient, the mean time from injury to evaluation was 44 days (range, 4-455 days). Pain level (VAPS) and functional outcome (DASH) were assessed; supination strength was normalized to the uninjured arm. RESULTS: The uninjured arm was stronger (P < .001), and peak torque varied with forearm position (P < .043). Peak torque was greater in pronation compared with supination, regardless of injury (P < .002). No differences were detected in supination strength as a result of forearm position or arm dominance. Supination strength did not correlate with time from injury to evaluation. One patient regained supination strength (115%) at 60° of pronation and 72% in neutral with a lengthy time from injury. VAPS (5 of 10) and DASH (39 of 100) scores decreased with time and did not relate to supination strength. CONCLUSION: Biceps tendon rupture led to a 60% decrease in supination strength in the neutrally oriented forearm. Peak torque observations can be explained using forearm moment arms. VAPS and DASH scores decreased with time but did not affect strength. We speculate that supination strength from pronation to neutral can improve as one strengthens the brachioradialis but strength deficits from neutral to supination are more difficult to overcome.

Effect of lesser tuberosity osteotomy size and repair construct during total shoulder arthroplasty.

BACKGROUND: Lesser tuberosity osteotomy has been shown to decrease postoperative subscapularis dysfunction. The purpose of this study was to determine the effect of osteotomy thickness and suture configuration on repair integrity. MATERIALS AND METHODS: One side of 12 matched-pair cadaveric shoulders was randomly assigned to either a thick osteotomy (100% of lesser tuberosity height) or a thin osteotomy (50% of height). Both sides of the matched pairs were given the same repair, either (1) compression sutures or (2) compression sutures plus 1 tension suture. This created 4 groups of 6 paired specimens. Computed tomography imaging was used to measure tuberosity dimensions before and after osteotomy to validate fragment height and area. The repairs were loaded cyclically and then loaded to failure. A video system measured fragment displacement. The percent area of osteotomy contact was calculated from the computed tomography and displacement data. RESULTS: The average initial displacement was less in the thin osteotomy groups (P = .011). Adding a tension suture negated this difference. A significant number of thin repair sites compared with thick repair sites remained intact during load-to-failure testing (P = .001). No difference occurred because of maximum load between the repair groups (P = .401), and construct stiffness was greater when a tension suture was used (P = .032). The percent area of osteotomy contact showed no differences between the osteotomy (P = .431) and repair (P = .251) groups. CONCLUSION: The study showed that thin osteotomies displaced less than thick osteotomies. Adding a tension band improved construct stability and eliminated some failure modes. Our ideal repair was a thin wafer with both tension and compression sutures. This construct had smaller total displacement, a high osteotomy percent contact area, and a high maximum load.

Molecular systematics of the Jacks (Perciformes: Carangidae) based on mitochondrial cytochrome b sequences using parsimony, likelihood, and Bayesian approaches.

The Carangidae represent a diverse family of marine fishes that include both ecologically and economically important species. Currently, there are four recognized tribes within the family, but phylogenetic relationships among them based on morphology are not resolved. In addition, the tribe Carangini contains species with a variety of body forms and no study has tried to interpret the evolution of this diversity. We used DNA sequences from the mitochondrial cytochrome b gene to reconstruct the phylogenetic history of 50 species from each of the four tribes of Carangidae and four carangoid outgroup taxa. We found support for the monophyly of three tribes within the Carangidae (Carangini, Naucratini, and Trachinotini); however, monophyly of the fourth tribe (Scomberoidini) remains questionable. A sister group relationship between the Carangini and the Naucratini is well supported. This clade is apparently sister to the Trachinotini plus Scomberoidini but there is uncertain support for this relationship. Additionally, we examined the evolution of body form within the tribe Carangini and determined that each of the predominant clades has a distinct evolutionary trend in body form. We tested three methods of phylogenetic inference, parsimony, maximum-likelihood, and Bayesian inference. Whereas the three analyses produced largely congruent hypotheses, they differed in several important relationships. Maximum-likelihood and Bayesian methods produced hypotheses with higher support values for deep branches. The Bayesian analysis was computationally much faster and yet produced phylogenetic hypotheses that were very similar to those of the maximum-likelihood analysis.