Faculty Bibliography

OBJECTIVE: To present a consecutive series of older patients with pubic rami fractures and evaluate their long term functional outcome. STUDY DESIGN: Retrospective. METHODS: Sixty-three consecutive community-dwelling, ambulatory patients who sustained a public rami fracture and were treated at one hospital were reviewed. Fifty-two of sixty-three patients (83%) had radiographic evidence of pubic rami fracture at initial presentation; in the remaining eleven patients, the diagnosis of pubic rami fracture was made after additional imaging studies. Sixty patients (95%) required hospitalization for pain control and progressive mobilization. RESULTS: The hospital length of stay for the sixty admitted patients averaged fourteen days; patients who had three or more associated medical comorbidities or required use of a cane or walker for ambulation prior to fracture were more likely to have been hospitalized greater than two weeks. Thirty-eight patients were available for one year minimum follow-up; thirty-five of thirty-eight patients (92%) were living at home, 84% had no or mild complaints of hip/groin pain, 92% had returned to their prefracture ambulatory status, and 95% had returned to their performance function in activities of daily living. CONCLUSIONS: 1) Elderly patients with pubic rami fractures utilize substantial healthcare resources based upon length of stay and need for home care services; and 2) those patients who survive have a good prognosis with regard to long term pain relief and functional outcome

Neuropathic arthropathy is a chronic, progressive degenerative disorder affecting one or more peripheral or vertebral articulations, which develops as the result of a disturbance in the normal sensory (pain or proprioceptive) innervation of joints. Diabetes, syphilis, and syringomelia are the most commonly associated clinical entities. When neuropathic arthropathy is suspected, careful clinical evaluation should be performed to identify an underlying neurologic disorder. Patient education, joint protection, and early recognition of fractures are the most important general management principles. Surgery can be considered in cases of advanced joint destruction when there is significant disability

An unconstrained cadaver ankle model was designed to reevaluate the effect of ankle mortise widening and syndesmotic fixation on the load-bearing characteristics of the tibiotalar joint. Tibiotalar contact area, centroid shift, and mean contact pressure were quantified using a pressure-sensitive film technique. Six fresh-frozen below-knee amputation specimens were axially loaded with 500 N in three positions: neutral, 10 degrees of dorsiflexion, and 20 degrees of plantarflexion. The tibiotalar contact area and centroid position for each specimen in its intact state were first determined and then compared with values obtained after syndesmotic fixation, mortise widening of 2 and 4 mm, and deep deltoid ligament transection. Syndesmotic fixation significantly decreased joint contact area but did not consistently affect centroid position. However, unlike earlier studies, which used more constrained ankle fracture models, mortise widening with or without deltoid rupture was not found to significantly affect contact area, centroid position, or joint contact pressure. When statically loaded, the talus moved to its position of maximal congruence in the mortise, rather than displacing laterally along with the lateral malleolus

OBJECTIVE: A biomechanical cadaver study was performed to compare the stability and ultimate strength of ten standard fixation techniques used for the treatment of surgical neck fractures of the proximal humerus. DESIGN: One hundred twenty (60 fresh frozen, 60 embalmed) proximal humerus specimens were selected and divided into two groups: fresh frozen specimens represented a nonosteopenic group and embalmed specimens an osteopenic group. Simulated fractures were created at the level of the surgical neck, reduced, and randomly assigned to one of ten methods of fixation (six fresh frozen and six embalmed specimens per fixation group). These constructs were then mechanically tested with the humeri oriented to create primarily shear loading of the fixation. RESULTS AND CONCLUSIONS: The T-plate and screws provided significantly stronger fixation (p < 0.005) in the fresh frozen specimens than all other methods. The Ender nails/tension band construct was the second strongest fixation technique, providing significantly stronger fixation (p < 0.01) than all the remaining techniques. Four Schanz pins with one pin placed through the greater tuberosity followed by the T-plate and screws provided the strongest fixation in embalmed specimens. Tension band fixation in both humeral groups was shown to provide the least effective fixation

A laboratory study was performed to compare the stability and ultimate strength of three standard fixation techniques for split-type lateral tibial plateau fractures. The three methods of fixation were (a) three 6.5-mm cancellous lag screws with washers; (b) two 6.5-mm cancellous lag screws with washers and an additional antiglide 4.5-mm cortical screw with washer; and (c) six-hole L-shaped buttress plate. Twelve pairs of embalmed mildly osteopenic lower extremities were used. Simulated split-type lateral tibial plateau fractures were created, reduced, and then instrumented in a matched pair design. The instrumented specimens were axially loaded to determine resistance to displacement, cyclically loaded to 10,000 cycles to determine dynamic stability, and then loaded to failure. There were no statistically significant differences found between resistance to displacement or failure strength as a function of either fragment size or sample bone density. On the basis of biomechanical stability, there appears to be no difference between the three fixation techniques tested. The results of this study suggest that use of an antiglide screw or buttress plate does not offer an advantage over lag screw fixation alone for the treatment of split type lateral tibial plateau fractures

A telemeterized shoulder prosthesis was developed and tested, first in vitro and then in a cadaver implantation. The prototype prosthesis was instrumented with 3 strain gauges fixed within a hollow, tapered neck element whose output was used to determine the load vectors experimentally applied to the humeral head. Testing demonstrated accuracy of force measurement resolution to within 5% of actual applied forces. This design seems feasible for further investigations to develop a totally implantable telemeterized prosthesis

A prospective analysis was performed involving 680 geriatric patients with hip fractures to determine whether the demographic profile of patients with femoral neck fractures was similar to that of patients with intertrochanteric fractures. All patients were community dwelling, cognitively intact, previously ambulatory elderly with femoral neck or intertrochanteric fracture. Three hundred fifty-eight patients (52.6%) sustained a femoral neck fracture; 322 (47.4%), an intertrochanteric fracture. Patients with an intertrochanteric fracture were significantly older, more likely to be limited to home ambulation, and were more dependent regarding basic and instrumental activities of daily living. After stratification by gender and adjustment for age, these differences remained significant in women only. There were no differences in age, prefracture ambulatory ability, or dependence in activities of daily living in men with either type of fracture