ABSTRACT
First metatarsophalangeal joint hemi-implant arthroplasty is commonly used for 1-sided degenerative joint disease. This study examined outcomes in patients that underwent hemi-arthroplasty using the BioPro hemi-implant. Twenty-three of 30 patients completed the 12-month follow-up between October 2001 and June 2003. Repeated measures multivariate analysis of covariance was used to consider the influence of the implant on a number of dependent variables, while controlling for the amount of first metatarsal head cartilage degeneration. The average amount of first metatarsal head cartilage degeneration visualized intra-operatively was 71.8% +/- 21.7%. From the preoperative to postoperative periods, the average hallux abductus angle went from 12.6 degrees +/- 6.5 degrees to 10.2 degrees +/- 5.3 degrees (P = 0.521), the average first intermetatarsal angle went from 11.0 degrees +/- 2.3 degrees to 10.5 degrees +/- 2.0 degrees (P = 0.434), the average first metatarsal declination angle went from 18.5 degrees +/- 4.1 degrees to 18.3 degrees +/- 4.1 degrees (P = 0.297), the average ACFAS score went from 41.2 +/- 11.6 to 80.4 +/- 8.8 (P = 0.003), average dorsiflexion went from 12.6 +/- 12.4 to 50.0 +/- 8.7 (P = 0.009), and average plantarflexion went from 8.0 +/- 8.0 to 17.5 +/- 6.7 (P < 0.001). Despite the presence of first metatarsal head cartilage degeneration, the ACFAS outcome score and the range of motion improved following implant arthroplasty, and these findings support the use of this procedure as a useful salvage intervention even in patients with pre-existing double-sided first metatarsophalangeal joint disease.
Subject(s)
Arthroplasty, Replacement/methods , Metatarsalgia/surgery , Metatarsophalangeal Joint/surgery , Adult , Aged , Female , Humans , Male , Metatarsalgia/diagnostic imaging , Metatarsophalangeal Joint/diagnostic imaging , Middle Aged , Multivariate Analysis , Prospective Studies , Radiography , Range of Motion, Articular , Treatment OutcomeABSTRACT
The purpose of this study was to determine the difference in pullout strength between cannulated and solid-core small-diameter bone screws. Cannulated screws from different manufacturers were compared against solid-core screws with 2.0-mm, 2.4-/2.5-mm, and 3.0-mm diameters. A synthetic material made to simulate bicortical bone was used as the test medium. The screws were extracted under servohydraulic control. There was no statistically significant difference between any of the cannulated and solid-core 2.0-mm screws used in this study (P <.05). In the 2.4-/2.5-mm screw tests, both of the cannulated screw designs had a significantly higher pullout strength when compared with the solid-core screw (P <.05). In the testing of 3.0-mm screw test, 1 of the cannulated screw designs showed a significantly higher pullout strength than the other cannulated and solid-core screws that were tested (P <.05). The results of this study suggest that small-diameter cannulated bone screws are similar in mechanical pullout strength to solid-core screws.
