Faculty Bibliography

Medial dislocation of the long head of the biceps branchii tendon is a rare occurrence and is often associated with degenerative or traumatic tears of the rotator cuff, specifically tears of the subscapularis tendon. Following a dislocation, the biceps tendon will assume either an intra- or extra-articular position depending on whether or not the subscapularis tendon detaches from its humoral insertion. Magnetic resonance imaging (MRI) has been found to provide valuable information concerning the location of the biceps tendon and the integrity of the rotator cuff. In this report, three patients with suspected dislocations of the biceps tendon are evaluated using MRI

Bilateral shoulder motor output measurements were obtained in 40 subjects with a Biodex dynamometer. The subjects included two groups, a younger group (20 to 30 years) and an older group (50 to 60 years). They were engaged in low to moderate levels of occupational and spare-time physical activity. Each subject performed three maximum effort shoulder movements in flexion/extension, abduction/adduction, and internal/external rotation at 60 degrees/sec and 120 degrees/sec. Side tested, axis, and speed were randomly selected. The findings indicate that a significant decline occurred in peak torque, work, and power for all axes of movement at both speeds when the older group was compared with the younger group. A decline in peak torque and work and a corresponding increase in power resulting from an increase in speed occurred in both age groups. The effect of age was the same at 60 degrees/sec and at 120 degrees/sec. Overall, no difference in dominant and nondominant motor function was seen in either the younger or older untrained men

Forty-two consecutive patients (20 men and 22 women, age range 39 to 78 years) with full-thickness rotator cuff tears underwent a comprehensive isokinetic strength assessment before and at 3-month intervals for 1 year after surgery. All patients underwent acromioplasty and rotator cuff repair and were treated with a standardized postoperative rehabilitation program. Isokinetic strength testing was performed in flexion/extension, abduction/adduction, and external/internal rotation at 60 degrees/sec. The unaffected contralateral shoulder was tested for comparison. Clinical outcomes were assessed with the University of California Los Angeles Shoulder Rating Scale (maximum = 35 points). The average University of California Los Angeles score was 31.2 by 1 year after operation. Patients with small and medium tears had an average rating of 33.5, whereas those with large and massive tears had an average score of 28.3. Strength increased gradually during the first postoperative year. The preoperative mean peak torque was 54%, 45%, and 64% of the uninvolved shoulder in flexion, abduction, and external rotation, respectively; after operation it increased to 78%, 80%, and 79% by 6 months and 84%, 90%, and 91% by 12 months. The greatest improvement in strength consistently occurred during the first 6 months after surgery. Patients also showed marked increases in both work and power. By 12 months after operation mean work had increased to 70% in flexion and abduction and 90% in external rotation of the uninvolved shoulder. Similarly, mean power had increased to 68%, 79%, and 90% of the uninvolved shoulder in flexion, abduction, and external rotation, respectively, by 12 months after operation. Recovery of strength correlated primarily with the size of the tear: for small and medium tears recovery of strength was almost complete during the first year, and for large and massive tears it was much slower and less consistent. By using isokinetic strength evaluation we found that recovery of strength after rotator cuff repair requires at least 1 year of rehabilitation

Five hundred and sixteen community-dwelling, ambulatory, geriatric hip fracture patients who were independent prior to fracture were followed prospectively to determine which patients regained their prefracture independent living status at 3-, 6-, and 12-month follow-up. At 3-, 6-, and 12-month follow-up, 78, 77, and 76% of the patients, respectively, had regained their prefracture independent living status. Analysis was performed to determine which pre- and postinjury factors were predictive of a patient regaining prefracture independent living status at 3, 6, and 12 months after fracture. Patients who were younger than age 85, independent in activities of daily living prior to fracture, independent in ambulation at hospital discharge, and who had three or more medical comorbidities were more likely to regain their prefracture independent living status

Various morphologic parameters of the coracoacromial region were quantified for five hominoid genera to examine the evolutionary development of the coracoacromial ligament (CAL) and its significance and relationship to shoulder function. No evolutionary correlation within the family Hominoidea was found for several calculated parameters obtained from osseous dimensions and CAL length. However, from an evolutionary analysis of the order Anthropoidea, it appears that the CAL is not solely a vestigial structure in humans but rather represents a stage in the development of the hominoid shoulder with the function of providing increased mechanical stability to the superior bony vault

Eighteen pairs of fresh frozen human upper extremities were selected and each randomized to 2 of 3 olecranon osteotomy and fixation technique groups: (1) transverse osteotomy with 0.062 Kirschner wire and tension band fixation; (2) chevron osteotomy with 6.5-mm cancellous lag screw and tension band fixation; and (3) oblique intraarticular osteotomy with 3.5-mm cortical lag screw and tension band fixation. The arms were mounted with the elbow at 90 degrees flexion and the wrist constrained; a dual linear displacement transducer across the osteotomy was used to determine angulation, translational displacement, and the total gap size. First the brachialis and then the triceps were incrementally loaded to 10 kg using a pulley and cable system to control force direction; the muscle load versus osteotomy displacement was recorded. Cycling with 10 kg was repeated 20 times with the brachialis and triceps alternately loaded and the osteotomy displacement remeasured. There were no statistically significant differences between the amounts of displacement for the 3 osteotomy and fixation techniques caused by either muscle action. The total displacement caused by the brachialis load for all techniques was appreciably greater than that of the triceps load. No significant increase in displacements occurred after 20 load cycles. These results suggest all 3 olecranon osteotomy and fixation techniques offer comparable stability, so the choice of technique should be left to the surgeon's preference

We studied the biomechanical behaviour of three sliding fixation devices for trochanteric femoral fractures. These were a titanium alloy sideplate and lag screw, a titanium alloy sideplate and dome plunger with cement augmentation, and a stainless-steel sideplate and lag screw. We used 18 mildly osteoporotic cadaver femora, randomly assigned to one of the three fixation groups. Four displacement and two strain gauges were fixed to each specimen, and each femur was first tested intact (control), then as a two-part fracture and then as a four-part intertrochanteric fracture. A range of physiological loads was applied to determine load-bearing, load-sharing and head displacement. The four-part-fracture specimens were subsequently tested to failure to determine maximum fixation strengths and modes of failure. The dome-plunger group failed at a load 50% higher than that of the stainless-steel lag-screw group (p < 0.05) and at a load 20% higher than that of the titanium-alloy lag-screw group (NS). All 12 lag-screw specimens failed by cut-out through the femoral head or neck, but none of the dome-plunger group showed movement within the femoral head when tested to failure. Strain-gauge analysis showed that the dome plunger produced considerably less strain in the inferior neck and calcar region than either of the lag screws. Inferior displacement of the femoral head was greatest for the dome-plunger group, and was due to sliding of the plunger. The dome plunger with cement augmentation was able to support higher loads and did not fail by cut-out through the femoral head.(ABSTRACT TRUNCATED AT 250 WORDS)

We prospectively studied 367 patients who had a fracture of the hip, to determine the effect of an operative delay on postoperative complications and on the one-year mortality rate. All of the patients were at least sixty-five years old, cognitively intact, living at home, and able to walk before the fracture. An operative delay was defined as an interval of three calendar days or more between the time of admission to the hospital and the operation. The operation was performed within two calendar days after admission in 267 (73 per cent) of the patients. When the factors of the patient's age and sex and the number of pre-existing medical conditions were controlled, it was found that an operative delay beyond this period approximately doubled the risk of the patient dying before the end of the first postoperative year. When the patient's age and sex and the severity of pre-existing medical conditions were controlled, there was also an increase in mortality associated with an operative delay, although this was not significant. With the numbers studied, an operative delay beyond two calendar days did not have a significant effect on the prevalence of complications during hospitalization. We concluded that an operative delay of more than two calendar days after admission is an important predictor of mortality within one year for elderly patients who have a fracture of the hip and who are cognitively intact, able to walk, and living at home before the fracture. Optimally, such patients should have the operation within two calendar days after admission to the hospital