Divergent elbow dislocation with radial shaft fracture, distal ulnar deformation, and distal radioulnar joint instability: an unclassifiable Monteggia variant.

Originally described by Monteggia and later classified by Bado, elbow dislocations with concurrent radial and ulnar shaft fractures with distal radioulnar joint (DRUJ) disruption are considered operative cases with high-energy injurious etiologies. Here, we present an unclassifiable Monteggia variant fracture suffered through a high axial load mechanism in a 47-year-old female. The fracture pattern initially exhibited included a divergent elbow dislocation, a radial shaft fracture, plastic deformation of the distal ulna, and DRUJ instability. Here we describe the pattern in detail, along with definitive treatment and clinical outcome at 1 year follow-up.

A comprehensive update on current fixation options for two-part proximal humerus fractures: a biomechanical investigation.

BACKGROUND: Recent advancements in implant technology offer updated options for surgical management that have been rapidly adopted into clinical practice. The objective of this study is to biomechanically test and compare the current fixation options available for surgical fixation of two-part proximal humerus fractures and establish load to failure and stiffness values. METHODS: Sixteen match-paired (32 total) fresh-frozen, cadaveric specimens were randomized to receive 1 of 4 fixation constructs following creation of an AO/OTA Type 11A3 (two-part) proximal humerus fractures. Fixation constructs tested consisted of 3.5 mm fixed angle plate (3.5-FAP), 4.5 mm fixed angle plate (4.5-FAP), humeral intramedullary nail (IMN), and a humeral intramedullary nail with a fixed angle blade (IMN-FAB). Specimen bone density was measured to ensure no adequate, non-osteoporotic bone. Constructs were tested for stiffness and ultimate load to failure and compared via one-way ANOVA analysis with subsequent post hoc Tukey HSD multiple group comparison statistical analysis. RESULTS: The IMN-FAB construct was significantly stiffer than the 3.5-FAP construct (123.8 vs. 23.9, p<0.0001), the 4.5-FAP construct (123.8 vs. 33.3, p<0.0001) and the IMN construct (123.8 vs. 60.1, p=0.005). The IMN-FAB construct reported a significantly higher load to failure than the 3.5-FAB construct (4667.3 N vs. 1756.9 N, p<0.0001), and the 4.5-FAP construct (4667.3 N vs. 2829.4 N, p=0.019, Table 2). The IMN construct had a significantly higher load to failure than the 3.5-FAP construct (3946.8 vs. 1756.9, p=0.001, Table 2). CONCLUSION: Biomechanical testing of modern fixation options for two-part proximal humerus fracture exhibited that the stiffest and highest load to failure construct was the IMN-FAB followed by the IMN, 3.5-FAP and then the 4.5-FAP constructs. However, prospective clinical trials with longer-term follow-up are required for definitive assessment of the ideal fixation construct for surgical management of two-part proximal humerus fractures.

Internal fixation of the distal humerus: a comprehensive biomechanical study evaluating current fixation techniques.

OBJECTIVES: The purpose of this study was to evaluate current fixation techniques in the operative fixation of distal humerus fractures, both with conventional and locked plating in both parallel and orthogonal orientation. METHODS: Twenty-eight upper extremities from 14 cadavers were prepared to create 4 implant testing constructs: Synthes locking plates (IMP1) (medial and posterolateral with lateral flange), Acumed parallel locking plates (IMP2), Smith & Nephew orthogonal locking plates (IMP3), and Synthes orthogonal 3.5-reconstruction plating (IMP4) (1 posterolateral and 1 medial). A 5-mm supracondylar osteotomy was made to simulate the fracture. Stiffness in axial and sagittal plane loading, fatigue properties (over 5000 cycles), and ultimate strength were determined for each construct by biomechanical testing. RESULTS: The parallel locking plates (IMP2) exhibited the highest stiffness in axial load and the highest ultimate strength (P < 0.05). No significant differences in sagittal plane stiffness and in the fatigue properties were seen across the locking plate groups, regardless of orientation. Locked plating constructs performed significantly better in all categories when compared with conventional nonlocked plating. Plastic deformation and implant loosening were the main modes of failure after ultimate strength test. CONCLUSION: Parallel locking plate configuration showed significantly higher stiffness to axial load and ultimate failure strength when compared with orthogonal locked and nonlocked plating. Locked plating configurations performed significantly better than nonlocked plating configurations, regardless of orientation. Although parallel orientation seems biomechanically superior, translation to the clinical setting may prove difficult when taking surrounding soft tissue and exposure into consideration.

Identification of the radial nerve during the posterior approach to the humerus: a cadaveric study.

OBJECTIVE: Identification of the radial nerve is necessary during the posterior approach to the humerus in an effort to maintain its integrity. Other than anatomic descriptions of the radial nerve with respect to osseous structures, there are few superficial intraoperative landmarks along the course of the traditional triceps-splitting approach to provide facile nerve identification. The objective of this study was to determine the reliability of using the anatomic intersection of the long and lateral heads of the triceps and the triceps aponeurosis as a superficial reference point for radial nerve identification during the posterior approach to the humerus. METHODS: Thirty adult human cadaver upper extremities as 15 matched pairs were used. Systematic identification and measurement from the point of intersection between the long and lateral heads of the triceps and the triceps aponeurosis to the distal most aspect of the radial nerve as it coursed the posterior humerus at its midaxial point was performed and recorded. RESULTS: Mean distance was found to measure 39.0 ± 2.1 mm (range, 36-44 mm), approximating a fixed distance, two finger breadths proximal to our identified point of intersection. Statistical analysis between the two matched pair groups yielded no significant difference in measured distances (P = 0.88). CONCLUSIONS: Our group has identified the point of intersection among three landmarks forming a point of intersection. This point is the confluence of the long and lateral heads of the triceps and the triceps aponeurosis. This serves as a visualized anatomic reference point during the posterior surgical exposure to the humerus and can be used to identify the radial nerve as it courses the posterior humerus.

Use of an "antibiotic plate" for infected periprosthetic fracture in total hip arthroplasty.

Periprosthetic fracture and infection are dreaded complications after total hip arthroplasty. We present the case of a 50-year-old man who suffered an early postoperative Vancouver B1 periprosthetic fracture, which was further complicated by concurrent infection after open reduction and internal fixation. We report the novel use of an antibiotic-impregnated cement coated locking plate during the staged treatment of concomitant periprosthetic fracture and chronic total hip arthroplasty infection. At 1-year follow-up, the patient is pain free and ambulating independently with full range of motion.

Forward progression of the helical blade into the pelvis after repair with the Trochanter Fixation Nail (TFN).

Unstable intertrochanteric and subtrochanteric fractures historically have been prone to inferior displacement of the femoral head as well as varus collapse. Efforts to mitigate these untoward outcomes have led to the evolution of the Trochanteric Fixation Nail (TFN) with its helical spiral blade. The TFN has many proposed advantages such as simplified insertion, less hardware, and improved resistance to "cutout" of cephallomedullary fixation. Previous case reports have shown spiral blade perforation through the femoral head and, in some cases, into the hip. However, to our knowledge, there have not been any reports describing the advancement of the helical spiral blade into the pelvic cavity. We present a case of forward advancement of the helical spiral blade through the femoral head and acetabulum into the pelvic cavity.