Jason Datta

Residual deformity after treatment of pediatric femur fractures with flexible titanium nails.

Introduction Procurvatum or anterior bow deformity is a potential complication after treatment of femur fractures with flexible titanium nails (FTNs). This article reports on a clinical evaluation of angulation after treating pediatric femur fractures with FTNs. The article also reports on a complementary investigation of potential causes of these deformities using a biomechanical model. Methods All pediatric femoral shaft fractures treated with FTNs over a 4-year period were reviewed. Fracture location, pattern, angulation, and nail shoe tip orientation were recorded from postoperative radiographs. Malunion was defined as greater than 10 degrees of angulation on the AP radiograph or greater than 15 degrees on the lateral view. As an adjunct to the clinical study, a synthetic femur model was created using midtransverse fractures. These femurs were nailed using 2 FTNs inserted so as to create constructs having the following combinations of nail shoe tip orientation: both anterior (AA), both posterior (PP), both neutral (NN), or 1 anterior and 1 posterior(AP). The resulting angular deformities noticeable upon gross inspection were then measured. Results Of the 70 fractures reviewed, malunion occurred in 16 fractures, of which 11 had increased anterior bow. A majority of malunions was observed in older children with middle third of the femur fractures. They were significantly more prevalent in transverse fractures compared with all other fracture patterns. Clinically, increased anterior bowing did not occur if 1 of the nails was positioned to resist procurvatum, as seen in the lateral radiograph. Depending on nail tip orientation, the biomechanical femur fracture model showed significant differences in mean deformations after nail placement: AA had 12.6 degrees of posterior bow compared with 14.8, 3.7, and 0.3 degrees of anterior bow for PP, NN, and AP, respectively. Conclusion Anterior bowing greater than 15 degrees is the most common malunion noted in this series of femur fractures that were nailed using FTNs. We conclude that final nail shoe tip orientation influences the likelihood of anterior bow deformity. The likelihood of large anterior bowing may be reduced if at least 1 of the nails is inserted with the tip pointing in an anterior direction. Level of Evidence/Clinical Relevance Level III.

The use of computed tomography angiography to define the prevertebral vascular anatomy prior to anterior lumbar procedures.

Study Design. Prospective cohort. Objective. To determine the efficacy of a single-slice computed tomography (CT) angiogram to define the prevertebral anatomy in patients undergoing an anterior lumbar spine procedure. Summary of Background Data. Preoperative planning with precise prevertebral anatomic details can help in mini-open anterior lumbar approaches. Methods. A total of 76 consecutive patients undergoing a minimal incision approach for anterior lumbar surgery were evaluated before surgery with CT angiography. The prevertebral anatomy was documented, and the patients were observed during treatment. Results. There were no complications related to CT angiography. This study directly influenced surgical decision making and the treatment options in 21% of patients. The vena caval confluence limited access to the L5–S1 disc in 3% of patients and at the L4–L5 disc in 92% of the patients. Prevertebral anatomic anomalies were found in 11.8% of patients. Atherosclerotic disease was discovered in 17% of the patients. The major complication rate was 7.5%. CT angiography correlated with intraoperative vascular anatomy in all cases. Conclusion. Preoperative CT angiography before anterior approaches was determined to be effective in evaluating the prevertebral vascular anatomy.

Incidence of dysphagia comparing cervical arthroplasty and ACDF

Study design Retrospective cohort from randomized prospective clinical trial. Objective Evaluate incidence of dysphagia between instrumented ACDF and a no-profile cervical disc arthroplasty. Summary of background data Dysphagia is a well-known complication following anterior cervical discectomy and fusion (ACDF) and the etiology is multifactorial. One potential source for postoperative dysphagia involves the anterior profile of the implant used. Hence, a no-profile cervical disc arthroplasty could theoretically have fewer soft tissue adhesions and a lower incidence of dysphagia. The purpose of this study is to compare the incidence of dysphagia at least 1 year postoperatively following ACDF with anterior plating and a no-profile cervical disc arthroplasty. Methods A cohort of 87 patients meeting the inclusion criteria for the prospective, randomized, multicenter IDE trial of ProDisc-C versus ACDF were evaluated for dysphagia. Forty-five patients were randomized to receive cervical arthroplasty and 42 patients were randomized to the ACDF and plate group. The Bazaz-Yoo dysphagia questionnaire was administered in a blinded fashion after completion of at least 12 months follow-up. Results Follow-up averaged 18.2 months and included 76 (87%) of the 87 enrolled, with 38 of the original 45 in the arthroplasty group and 38 of the original 42 in the ACDF group. Six of 38 (15.8%) in the arthroplasty group versus 16 of 38 (42.1%) in the ACDF group reported ongoing dysphagia complaints. This was found to be statistically significant (P = .03). Conclusion This study suggests a significantly lower rate of dysphagia with a no-profile cervical disc arthroplasty compared to instrumented ACDF for single level disc disease between C3-7. Though there are many potential etiologies, we hypothesize this is related to the lack of anterior hardware in the retropharyngeal space. Operative technique, operating time, and significant midline retraction did not seem to result in more dysphagia complaints. Future studies comparing cervical disc arthroplasty and no-profile fusion devices may help delineate the effect that anterior instrumentation profile has on postoperative dysphagia.