Evaluation of ultrasonography as a diagnostic technique in the assessment of rotator cuff tendon tears.

In this study we assessed the clinical usefulness of ultrasonography as a modality in the diagnosis of rotator cuff tears. One hundred twenty patients with preoperative ultrasonography were analyzed by diagnostic arthroscopy to evaluate rotator cuff integrity. Two groups, 61 patients with a positive ultrasonogram and 59 patients with a negative ultrasonogram, were analyzed. The 61 patients with a positive ultrasonogram preoperatively were found to have 42 full-thickness tears and 19 partial-thickness tears. Diagnostic arthroscopy confirmed a sensitivity of 95% for the full-thickness tears and 41% for the partial-thickness tears. In the 59 patients with negative ultrasonography, the specificity for full-thickness tears was 93% and in the 19 partial-thickness tears it was 91%. Our conclusion is that ultrasonography is an effective modality for the assessment of full-thickness tears, but not partial-thickness tears.

STR primer concordance study.

Over 1500 population database samples comprising African Americans, Caucasians, Hispanics, Native Americans, Chamorros and Filipinos were typed using the PowerPlex 16 and the Profiler Plus/COfiler kits. Except for the D8S1179 locus in Chamorros and Filipinos from Guam, there were eight examples in which a typing difference due to allele dropout was observed. At the D8S1179 locus in the population samples from Guam, there were 13 examples of allele dropout observed when using the Profiler Plus kit. The data support that the primers used in the PowerPlex 16, Profiler Plus, and COfiler kits are reliable for typing reference samples that are for use in CODIS. In addition, allele frequency databases have been established for the STR loci Penta D and Penta E. Both loci are highly polymorphic.

Glenohumeral kinematics and capsulo-ligamentous strain resulting from laxity exams.

OBJECTIVE: Identification and quantification of strain in shoulder capsular-ligamentous structures during clinical exams and validation of this testing on cadavers. METHODS: Mercury strain gauges were sutured in seven locations on shoulders from cadavers. An electromagnetic tracker quantified humeral head translations during laxity exams. Strain and humeral position were acquired during performance of Sulcus, Feagin, Apprehension, Load and Shift, Drawer, and Hawkins tests. RESULTS: Anterior humeral head translation in neutral position was primarily constrained by the coracohumeral ligament. With the arm abducted, anterior middle and inferior ligaments also became active. External rotation and abduction activated inferior and middle capsules. Posterior capsule constrained motion for posterior tests in neutral and abduction. Superior and inferior capsular ligaments were active during inferior tests in neutral position. With abduction, inferior ligaments provided primary translation constraint. CONCLUSION: Study of kinematics and strain evaluation on cadavers can yield useful information on mechanisms of glenohumeral instability. Relevance This study clarifies the contribution of specific structures of the shoulder to strain in the joint capsule. It also identifies which structures are challenged by provocative laxity exams commonly used by orthopaedic physicians.