Unicortical and bicortical plating in the fixation of comminuted fractures of the clavicle: a biomechanical study

Biomechanical and clinical evaluation of minimal invasive plate osteosynthesis for two-part clavicle shaft fractures

BACKGROUND

Many surgical treatment methods exist for clavicle shaft fractures. A locking compression plate (LCP) fixation with three screws per fracture side is commonly used. For certain fractures a stabilization with 2 screws per side is potentially suitable, offering the advantage of reduced soft tissue approach, while avoiding the disadvantages of minimally-invasive nailing at the same time. This hypothesis was evaluated biomechanically and clinically.

METHODS

Four treatment procedures were investigated biomechanically using composite human clavicle specimens. A load-to-failure test was performed using a three-point cantilever test. In group 1, a simple shaft fracture was simulated and stabilized with 2 screws per fracture side (5-hole LCP). In the second group 3 screws per side (7-hole LCP) were used. In group 3, a non-reduced fracture zone was simulated and treated with 3 screws per side (7-hole LCP). In group 4, an anatomically reduced fracture zone was simulated and treated with 3 screws per side (7-hole LCP). Furthermore 27 patients treated with a short plate and 2 screws per side (similar to group 1) were assessed after a minimum follow-up of 12 months (Constant and DASH Score).

RESULTS

The maximum load-to-failure of group 1 was 367N. We observed the highest load-to-failure in group 2 with 497N and the lowest in group 3 with 90N. In group 4 a maximum load-to-failure of 298N could be evaluated. There was no significant difference in load-to-failure between the treatment of a simple clavicle fracture using 5- or 7-hole LCP (p = 0.121). However, we found a significant difference of load-to-failure between the simple and anatomically reduced fracture using a 7-hole plate (p = 0.014). The mean constant score of the surgically treated patients was 95 and the DASH score 3.0. Fracture consolidation was observed in 96.3%.

CONCLUSIONS

For certain non-fragmented and well interlocking 2-part fractures, a plate osteosynthesis fixed with only 2 screws per fracture side might offer sufficient biomechanical stability, better soft tissue preservation and comparable fusion rates compared to the operative treatment with 3 screws per side. However, the maximum load-to-failure of the 7-hole LCP was higher than of the 5-hole LCP, but this difference was not statistically significant.

TRIAL REGISTRATION

Approval from the ethics committee of the Technical University of Dresden was retrospectively obtained (EK 588122019).

Clinical outcome and operative cost comparison: Locked compression plate versus reconstruction plate in midshaft clavicle fractures

OBJECTIVE

The aim of this study was to compare the clinical outcomes and operative cost of a locked compression plate (LCP) and a nonlocked reconstruction plate in the treatment of displaced midshaft clavicle fracture.

METHODS

From January 2013 till March 2018, a total of 55 patients with acute unilateral closed midshaft clavicle fracture were treated with either a 3.5-mm pre-contoured LCP [32 patients; 25 men and 7 women; mean age: 35 years (range: 19-63 years)] or a 3.5-mm nonlocked reconstruction plate [23 patients; 20 men and 3 women; mean age: 31.4 years (range: 17-61 years)]. The clinical outcomes in terms of fracture union, Quick Disability of Arm, Shoulder and Hand (DASH) score, implant irritation, failure rate, and reoperation rate were evaluated retrospectively. The patient billing records were reviewed to obtain primary operation, reoperation, and total operative cost for midshaft clavicle fracture. These values were analyzed and converted from Malaysia Ringgit (RM) to United States Dollar (USD) at the exchange rate of RM 1 to USD 0.24. All patients were followed up for at least one-year duration.

RESULTS

The mean time to fracture union, implant irritation, implant failure, and reoperation rate showed no significant difference between the two groups of patients. The mean Quick DASH score was significantly better in the reconstruction plate group with 13 points compared with 28 points in the LCP group (p=0.003). In terms of total operative cost, the LCP group recorded a cost of USD 391 higher than the reconstruction plate group (p<0.001).

CONCLUSION

The 3.5-mm reconstruction plate achieved not only satisfactory clinical outcomes but was also more cost-effective than the LCP in the treatment of displaced midshaft clavicle fractures.

LEVEL OF EVIDENCE

Level III, Therapeutic study.

Finite element analysis of spiral plate and Herbert screw fixation for treatment of midshaft clavicle fractures

Both spiral plate and Herbert screw fixations have been clinically adopted for treating midshaft displaced clavicle fractures. However, the biomechanical properties of the 2 implant fixations have not yet been thoroughly evaluated. Here we report the results of a finite element analysis of the biomechanical properties of midshaft clavicle fractures treated with Herbert screw and spiral plate fixation. Hebert screw fixation showed stress distribution similar to intact clavicle under all loading conditions, but provided less stability than did spiral plate fixation. Postoperatively, excessive shoulder activities and weight-bearing should be avoided. Spiral plate fixation provides greater stability, but is associated with stress shielding. These results demonstrate that Herbert screw fixation is suitable for the treatment of simple displaced clavicluar fractures, but excessive shoulder activity and weight-bearing should be avoided after the operation. Therefore, spiral plate fixation may be preferred for patients requiring an early return to activity.