Fixation technique influences osteogenesis of comminuted fractures

Biological Osteosynthesis Versus Traditional Anatomic Reconstruction of 20 Long-Bone Fractures Using an Interlocking Nail: 1994-2001

OBJECTIVE

To observe differences in surgical and healing times as well as complication rates in dogs with a comminuted long-bone fracture stabilized with an interlocking nail (IN) using either anatomic or biologic repair.

STUDY DESIGN

Retrospective study.

ANIMALS

Twenty client-owned dogs with comminuted long-bone fractures.

METHODS

Medical records for dogs with fractures repaired during a 7-year period were reviewed; 20 dogs had repair with an IN nail and radiographic evidence of healing. These 20 dogs where divided into 2 groups, anatomic (11 dogs) and biological (9) repair, for statistical evaluation. Surgical and healing time and complication rates were compared between groups.

RESULTS

Median surgical times were: anatomic (95 minutes) and biologic (110 minutes; P=.06). Median healing times were anatomic (8 weeks) and biologic (6 weeks; P=.04). No statistical differences were observed in complication rates (the likelihood that a case required a second surgery [P=.58], the likelihood of a complication that was managed non-surgically [P=.27]). Use of a bone graft did not shorten healing times (P=.55).

CONCLUSIONS

Biological osteosynthesis provides clinical advantages over anatomic reconstruction with respect to a reduction in surgical and healing time without increasing complication rates.

CLINICAL RELEVANCE

Highly comminuted long-bone fractures can be successfully repaired using an IN without reconstructing the fracture fragments in dogs.

Surgical treatment of pediatric femoral shaft fractures

PURPOSE OF REVIEW

Femoral shaft fractures are among the most common fractures in children. Depending on the patient's age, fracture location, pattern, mechanism of injury, and associated injuries, several different treatment options exist. The purpose of this review is to discuss these different clinical situations and the recommended treatment methods, as well as to characterize the latest literature and recommendations.

RECENT FINDINGS

In the past several years, there have been significant changes in the approach to the treatment of pediatric femoral shaft fractures, particularly in school-aged children. Young children have traditionally been treated conservatively with good results, and this method is still currently advocated. Adolescents over the age of 12 are generally treated with rigid intramedullary rods. However, in children between the ages of 5 and 12, new surgical treatment modalities have been tested with good outcomes, and, as new data emerge, these methods are becoming preferable to conservative treatment.

SUMMARY

Children who sustain femoral shaft fractures can present difficult challenges to both orthopedists and pediatricians. A recent shift in treatment in children between ages of 5 and 12 from nonoperative to surgical intervention has led to shorter hospital stays and earlier return to activity with reliable fracture healing.

Percutaneous plating for unstable tibial fractures

Twenty-four unstable tibial fractures were stabilized with a narrow limited contact-dynamic compression plate inserted using a percutaneous plating technique under fluoroscopic guidance. The major indication for this technique was a tibial fracture for which intramedullary nailing would be difficult. There were 16 proximal or distal metaphyseal fractures and 5 segmental fractures in adults and 3 mid-shaft fractures in adolescents who still had an open physis. Of the 24 fractures, 22 healed without a second procedure; the two failures included one that required an early bone graft for severe comminution and another with a superficial infection that healed after early removal of the plate. There were no other infections. There were three cases of screw breakage, but they did not require a further procedure. At the final follow-up, one patient had healed with 5 degrees varus alignment and another with 10 degrees external rotation. All the patients had good knee or ankle function. We are confident that the percutaneous plating technique to treat unstable tibial fractures for which intramedullary nailing would be difficult will prove to be an alternative stabilization method, as it avoids the risk of infection or soft tissue compromise.

Distal tibia metaphyseal fractures treated by percutaneous plate osteosynthesis

Twenty-one patients with fractures of the distal tibial metaphysis, some with minimal displacement in the ankle, were treated by percutaneous plate osteosynthesis with a narrow limited contact-dynamic compression plate. Using the classification by the Arbeitsgemeinschaft für Osteosynthesefragen and Orthopaedic Trauma Association, 17 fractures had no articular involvement, whereas four included intraarticular extension. At final followup (mean, 20 months), all the fractures healed without second procedures and the mean union time was 15.2 weeks. One patient had malalignment of the limb with 10 degrees internal rotation, but there were no angular deformities greater than 5 degrees or any shortening greater than 1 cm. All patients had excellent or satisfactory ankle function. There were no infections or any soft tissue compromise. Percutaneous plate osteosynthesis is a safe and worthwhile method of managing such fractures, which avoids some of the complications associated with conventional open plating methods.

[Disorders in fracture healing]

INTRODUCTION

Bone fracture healing is a complex cascade of events at cellular and biochemical levels, that ends by complete structural and functional restoration of a damaged bone. Impaired healing develops in 5-10% of all fractures, and manifests as delayed union or non-union. This paper deals with the problem of impaired healing as well as with methods of fracture healing enhancement.

CAUSES OF IMPAIRED FRACTURE HEALING

There are many factors causing impaired fracture healing (inadequate vascularization, mechanical causes, infection, etc.), and it is very important to recognize the principle cause of delayed union and non-union, since therapy is based on eliminating the factor that causes it.

FRACTURE HEALING ENHANCEMENT

Through constant attempts to find adequate solutions and procedures in order to resolve the problem of impaired fracture healing, many alternatives in treatment of impaired healing have been developed. Some of these procedures may also be useful in treatment of fresh fractures, especially when it comes to fractures that are prone to delayed union and non-union more than usual. All currently known methods of healing enhancement may be classified as biological, mechanical and biophysical.

CONCLUSION

Certain methods are in clinical use for several decades. The newest methods, such as locally applied growth factors, composite biosynthetic grafts, gene therapy and systemic approaches are studied all around the world, and are on the verge of clinical application. Due to impressive number of therapeutic options, certain therapeutic procedures of choice will be developed for specific impairments.

Effects of one-plane and two-plane external fixation on sheep osteotomy healing and complications

OBJECTIVES

Comparison of one-plane and two-plane external fixation in terms of successful healing, incidence of complications, and biomechanical stability in a sheep model.

BACKGROUND

Rigid fixation is preferred in open and comminuted fractures with a reduced blood supply, preventing infection and healing delay, but more often a flexible device is recommended even in unfavourable healing conditions.

METHODS

The left tibiae of fifteen sheep were osteotomized and laterally fixed with a four-screw unilateral fixator frame (axial stiffness 183 N/mm) to a 3 mm gap size. In 9 of 15 sheep, an additional four-screw unilateral external fixator was anterolaterally attached (total axial stiffness of both frames 388 N/mm). After sacrificing, quality of osteotomy healing was assessed by mechanical and radiological evaluations. Osteogenesis was measured using fluorescence microscopy.

RESULTS

Two distal fractures through the pin-tracks, three non-unions and four deep infections occurred after two-plane fixation. These failures excluded, osteotomy healing showed inferior results after two-plane fixation with reduced callus formation, bone mineral content, and bending stiffness amounts, respectively. Osteogenesis was halved following two-plane fixation in the remaining sheep.

CONCLUSIONS

Two-plane fixation was not sufficient to reach successful osteotomy healing in our study. While higher rigidity was expected to prevent complications, healing in this group might have been disturbed by a reduced blood supply. The optimal stabilisation for a given fracture depends on many factors, including the biomechanical and biological environment.

RELEVANCE

Considering our results and the literature discussed in this manuscript, good bone healing with minor risks of infections can be achieved using an unilateral one-plane fixator with only four screws, and its application on a muscle free position like the medial and anterior site of the sheep tibia.