Narrow Results

Background: Internal fixation modalities of unstable (>50 percent articular involvement) middle phalangeal volar lip fracture-dislocations include interfragmentary screw and volar buttress plating. This study investigates the mechanical properties (yield strength, ultimate tensile strength, and stiffness) of interfragmentary screw (IS), simple buttress plating (BP) and buttress plating with subchondral screw (BP+S).

Methods: Fifteen cadaveric digits (5 index, 5 middle, and 5 ring) were prepared by excising its skin envelope and flexor tendons while preserving the structures around the proximal interphalangeal joint. An oblique osteotomy involving 50 percent of the articular surface was performed, and this was fixed with based on its study group: interfragmentary screw (IS), simple buttress plating (BP) and buttress plating with subchondral screw (BP+S). These specimens were then loaded to failure.

Results: Yield strength was as follows: BP+S (33.5±9.76 N), IS (13.6±5.46 N), and BP (8.1±3.84 N). Ultimate tensile strength was as follows: BP+S (49.1±21.4 N), IS (15.6±5.19 N), and BP (8.86±3.99 N). Stiffness was as follows: BP+S (4.77±1.32 N/mm), IS (2.44±0.86 N/mm), and BP (1.84±0.71 N/mm).

Conclusions: A buttress plate and screw construct confers significantly more stability than either interfragmentary screw or buttress plate only fixation in an experimental model.

Background: The thumb plays an important role in the function of the hand. Sensate reconstruction of the pulp is important in restoring function to the thumb. The aim of this study is to present outcomes of a sensate islanded first dorsal metacarpal artery (FDMA) flap used for the reconstruction of skin defects of the thumb.

Methods: Patients who had a FDMA flap reconstruction of thumb pulp defects in the orthopaedics and traumatology clinic of affiliated hospital were included in the study. This included eight thumbs of eight patients. The range of motion, sensation and cosmetic satisfaction in the donor and recipient areas were evaluated at a minimum of 2-year follow-up.

Results: There were no partial or complete flap failures. The mean static 2-point discrimination was 15 mm and the mean Semmes–Weinstein monofilament test score was 3.93. Cortical re-orientation was observed in 65% of patients. Near normal range of motion and Kapandji scores were regained in all patients.

Conclusions: Excellent motion and sensory outcomes were obtained following the FDMA flap reconstruction of thumb pulp defects. The donor morbidity of the flap is minimal, and this flap can be considered as one of the primary options for reconstruction of thumb pulp defects.

Level of Evidence: Level V (Therapeutic)