Complex Distal Humerus Fractures Research Articles

Revisionsendoprothetik des Ellenbogens

Total elbow arthroplasty (TEA) is gaining in popularity. An elbow prosthesis is nowadays no longer regarded as a salvage procedure for low demand patients but is increasingly used in younger, active patients with higher demands. In elderly patients TEA is more and more accepted as a primary treatment method for osteoporotic complex distal humerus fractures. Nevertheless, TEA is technically demanding and associated with a higher complication and revision rate compared to e.g. hip prostheses. Increasing implantation rates in a juvenescent population will lead to a considerable increase in revision rates. Most common causes are aseptic and septic loosening as well as implant failure and instability. Cemented semi-constrained prostheses are mostly used for revision elbow arthroplasty. This article deals with the causes of revision elbow arthroplasty and describes the operative technique of revision of total elbow arthroplasty.

Functional results of the parallel-plate technique for complex distal humerus fractures

We evaluated functional results of patients treated with open reduction and internal fixation with the parallel-plate technique for complex distal humerus fractures. Twenty-one patients (14 males, 7 females; mean age 47 years; range 16 to 85) underwent open reduction with olecranon osteotomy and internal fixation with the parallel-plate technique for distal humerus fractures accompanied by highly intra-articular or metaphyseal comminution (n=10), intra-articular comminution and osteoporosis (n=7), and intra-articular and metaphyseal comminution with bone loss (n=4). According to the AO classification, there were 12 C3, six C2, and three C1 type fractures. Eight patients had open fractures. The mean time to surgery was six days (range 1 to 17 days). Functional results were evaluated using the Mayo elbow performance score, Jupiter elbow score, and DASH (Disabilities of the Arm, Shoulder and Hand) score. The mean follow-up was 28 months (range 12 to 48 months). The mean total range of motion was 90.2+/-31.1 degrees, flexion was 118.1+/-17.4 degrees, and extension was 27.8+/-17.4 degrees. The mean Mayo elbow performance score and DASH score were 86.1+/-12.6 and 7.6+/-9.5, respectively. According to the Jupiter elbow scores, the results were excellent in seven patients, good in 11 patients, moderate in two patients, and poor in one patient. Radiographically, solid union was achieved in all the patients. Heterotopic ossification of varying degrees was seen in seven patients, two of whom underwent resection of heterotopic ossification due to severe limitation of movement. Debridement was performed in one patient due to the development of deep infection. Chondrolysis of the elbow occurred in one patient. Patients with open fractures had significantly lower range of motion than those with closed fractures (p<0.05), but the Mayo elbow performance score and DASH score did not differ significantly in this respect (p>0.05). Functional results are satisfactory in distal humerus fractures treated with stable osteosynthesis and parallel-plate technique that allow early active motion.

Biomechanical comparison of two different periarticular plating systems for stabilization of complex distal humerus fractures

Complex intra-articular distal humerus fractures are relatively uncommon injuries but are fraught with poor outcomes such as malunion, elbow stiffness and deformity. Various types of internal fixation screw-plate constructs have been developed to improve fixation. Specifically, a 90 degrees offset periarticular system lowers the profile on the lateral epicondyle, yet it is unclear how this design compares to other plate constructs. This study compared the mechanical stiffness and plate surface strains between two types of constructs for stabilization of complex distal humerus fractures. Identical bi-columnar segmental intra-articular fractures were created in ten epoxy composite left humeri. Models were randomly assigned to two groups (n=5/group) with either parallel plates or perpendicular plates. Rosette strain gages were placed at the most distal possible space on the lateral plate for both constructs. Models were mechanically tested with estimates of physiologic loads in flexion, extension, varus, valgus axial compression and axial torsion. Data for mechanical stiffness, transverse plate strain and longitudinal plate strain were compared with a one-way ANOVA (P<0.05). There was no statistical difference in stiffness in any direction. The longitudinal strain for the 90 degrees construct was significantly lower in axial compression. The 180 degrees system demonstrated significantly lower transverse strains during axial torsion. Both systems demonstrated similar mechanical stiffness theoretically providing similar fracture stabilization. Plate strain differences may affect fragment position, but it is unclear how much plate loading occurs in vivo. Surgeon experience and preference may dictate the choice of a plate construct for this fracture configuration.