Biomechanical Analysis of Combined Medial Calcar and Lateral Locked Plating Versus Isolated Lateral Locked Plating of Proximal Humerus Fractures.

OBJECTIVE: Medial calcar buttress plating combined with lateral locked plating is biomechanically tested against isolated lateral locked plating in synthetic humeri models for the treatment of proximal humerus fractures. METHODS: Proximal humerus fractures (OTA/AO type 11-A2.1) were manufactured in 10 pairs of Sawbones humeri models (Sawbones, Pacific Research Laboratories, Vashon Island, WA). Specimen were randomly assigned and instrumented with either medial calcar buttress plating combined with lateral locked plating (CP) or isolated lateral locked plating (LP). Nondestructive torsional and axial load tests were performed to evaluate construct stiffness. Large-cycle axial tests were conducted followed by destructive ramp-to-failure tests. Cyclic stiffness was compared in both nondestructive and ultimate failure loads. Failure displacement was recorded and compared between groups. RESULTS: The addition of medial calcar buttress plating to lateral locked plating constructs significantly increased the axial ( P < 0.01) and torsional ( P < 0.01) stiffness of the construct compared with isolated lateral locked plating by 95.56% and 37.46%, respectively. All models demonstrated greater axial stiffness ( P < 0.01) after 5000 cycles of axial compression, not dependent on the fixation method. During destructive testing, the CP construct withstood 45.35% larger load ( P < 0.01) and congruently exhibited 58% less humeral head displacement ( P = 0.02) before failure when compared with the LP construct. CONCLUSION: This study demonstrates the biomechanical superiority of medial calcar buttress plating when combined with lateral locked plating as compared with isolated lateral locked plating of OTA/AO type 11-A2.1 proximal humerus in synthetic humeri models.

Circumventing Acute Compartment Syndrome: Outcomes from a Cadaver-based Course in Fasciotomy Procedural Skills.

Acute compartment syndrome (ACS) represents a surgical emergency requiring effective, complete fasciotomy. The purpose of this study is to evaluate cadaver-based training on the ability of practicing general surgeons to effectively perform upper extremity, thigh, and leg fasciotomies. One hundred seventeen general surgeons underwent a 2-day, cadaver-based course with formative and summative assessments based on validated scoring tools. Overall performance and critical item scores were recorded and compared utilizing analysis of variance with repeated measures and eta-squared values to evaluate effect size. For all three procedures, post-training scores were significantly improved when compared with pre-training scores (p < 0.001). Mean pre-training score for lower leg fasciotomy met the standard for competent performance of the procedure (total score > 80), whereas neither thigh nor upper extremity performance scores met this standard before training. This 2-day, cadaver-based course improves the ability of practicing general surgeons to effectively and independently perform upper extremity, thigh, and lower leg fasciotomies. (Journal of Surgical Orthopaedic Advances 32(4):238-241, 2023).