Do foot injuries significantly affect the functional outcome of multiply injured patients?

OBJECTIVE: To assess the functional outcome of multiply injured trauma patients with foot injuries and to determine which outcome measures are most appropriate for this assessment. DESIGN: Prospective, matched pair analysis. SETTING: University-affiliated Level I trauma center with a prospectively entered trauma database. PATIENTS: Twenty-eight multiply injured patients with foot injuries were randomly identified in our prospective trauma database (Group 1). The patients in Group 1 were randomly matched in a blinded fashion to twenty-eight multiply injured patients without foot injuries who were selected from the entire group of patients in our trauma database (Group 2). The patients were matched by age, sex, length of follow-up, and Injury Severity Score. MAIN OUTCOME MEASURES: Three outcome tools were used: the Short Form 36 (SF-36), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the modified Boston Children's Hospital Grading System. RESULTS: The outcome of multiply injured patients with foot injuries was significantly worse than that of patients without foot injuries when using any of the three outcome measures (SF-36, p = 0.008; WOMAC, p = 0.00007; modified Boston Children's score, p = 0.001). The outcome of patients with foot injuries was worse than that of those without foot injuries in five of the eight components of the SF-36 score (physical functioning, p = 0.0004; role physical, p = 0.01; bodily pain, p = 0.01; social functioning, p = 0.01; role emotional, p = 0.006). The outcome of patients with foot injuries was worse than that of patients without foot injuries in all three components of the WOMAC (pain score, p = 0.0004; stiffness score, p = 0.007; physical function score, p = 0.00006). For the patients with foot injuries, there was strong correlation across all three scales (SF-36 vs. WOMAC, r = 0.84; SF-36 vs. modified Boston Children's Hospital, r = 0.88; WOMAC vs. modified Boston Children's Hospital, r = 0.78). CONCLUSIONS: The SF-36, WOMAC, and modified Boston Children's Hospital Grading System are all useful in assessing the outcome of multiply injured patients with foot injuries. The outcome of these patients is poor when using any of these measures. Foot injuries cause significant disability to multiply injured patients. More attention should be given to these injuries, and more aggressive management should be considered to improve the outcome of this group of multiply injured patients.

Pulmonary and systemic fat embolization after medullary canal pressurization: a hemodynamic and histologic investigation in the dog.

BACKGROUND: The potential to produce fat embolism may be important in determining the ideal method and timing of fracture treatment in patients with preexisting lung injury. METHODS: Four dogs underwent femoral and tibial canal reaming and pressurization. Blood gas samples were analyzed, and pulmonary arterial pressure was monitored at 1 and 72 hours. Animals were killed 72 hours postoperatively, and the lungs, kidneys, and brain were examined histologically and compared with equivalent specimens from four control dogs that had not undergone femoral and tibial canal reaming and pressurization. RESULTS: Postmortem, intravascular fat persisted for 72 hours after induction of pulmonary fat embolism. Mean PaO2 was unchanged from baseline at 72 hours after canal pressurization. Canal pressurization caused a sustained increase in pulmonary arterial pressure (p=0.02) for 1 hour after canal pressurization. The mean pulmonary edema score at 72 hours was 29+/-3. Only a scant polymorph infiltrate (zero to two polymorphs per high-power field) was present at any time. No hyaline membranes were seen at any time. The percentage area occupied by intravascular fat in the lungs was 0.0214+/-0.0058 at 72 hours. No signs of ischemia or inflammation were seen in either the cerebral or the renal specimens. CONCLUSION: This study is the first to show that intravascular fat persists in the lungs, kidneys, and brain for 72 hours after canal pressurization and, by itself, does not cause pathologic evidence of acute inflammation.

Quantitative assessment of bone injury and repair after reamed and unreamed locked intramedullary nailing.

BACKGROUND: Cortical reaming and intramedullary nail insertion injure the medullary vascular system. Little attention has been directed toward quantitative assessment of bone injury and repair after locked intramedullary nailing of long-bone fractures with and without reaming. The effects of reamed versus unreamed locked intramedullary nailing on cortical porosity and new bone formation were compared in a sheep fractured tibia model. METHODS: After creation of a standardized spiral fracture by three-point bending with torsion, each tibia was stabilized by insertion of a locked intramedullary nail. Ten sheep were randomized into two groups, one that had reaming before nail insertion and one that did not. Fluorochromes were given 2 weeks (xylenol orange), 6 weeks (calcein green), and 12 weeks (tetracycline) postoperatively. All animals were killed at 12 weeks postoperatively. Cortical porosity and new bone formation were determined for the proximal diaphysis, fracture site, and distal diaphysis. RESULTS: Overall cortical porosity was greater with reamed nails than with unreamed nails (p = 0.02). Porosity in the inner cortex (18.3% (reamed) vs. 14.3% (unreamed); p = 0.09) and outer cortex (16.8% (reamed) vs. 12.2% (unreamed); p = 0.04) was greater in the reamed group. With reamed nails only, there was less new bone formation at 2 (p = 0.04) and 12 (p = 0.05) weeks in the inner cortex compared with the central cortex and outer cortex. Overall, there was no difference between reamed and unreamed nails in the amount of new bone formation at 2, 6, or 12 weeks. CONCLUSIONS: This study demonstrates that greater injury or overall cortical porosity is associated with reamed nail insertion. There is no difference, however, between the amount of new bone formation after reamed and unreamed nail insertion. Nail insertion without reaming may be initially advantageous when tibial cortical vascularity is compromised, by limiting further injury to cortical bone. This may be important with open tibial fractures in which there is a significant risk of infection after injury. Between 2 and 12 weeks after injury, neither reamed nor unreamed nail insertion seems to have a significant advantage with respect to the amount of new bone formation that occurs.

Validity of observer-based aggregate scoring systems as descriptors of elbow pain, function, and disability.

Current elbow-scoring systems are based on the observer-derived assessment of a variety of clinical and functional criteria, which are scored separately and then aggregated. The aggregate score then is assigned a categorical ranking that ranges from excellent to poor. The developers of different elbow-scoring systems have chosen different outcome criteria, assigned different weights to each criterion, and accorded different ranges of values to each categorical ranking. Five different elbow-scoring systems (the Mayo elbow-performance index and the systems of Broberg and Morrey, Ewald et al., The Hospital for Special Surgery, and Pritchard) were used to evaluate the same group of patients. The validity of the scoring systems was determined with use of visual-analog scales for the assessment of pain and function, patient and physician-derived ratings of the severity of impairment of the elbow, and two functional questionnaires completed by the patient (the Disabilities of the Arm, Shoulder and Hand questionnaire and the Modified American Shoulder and Elbow Surgeons patient self-evaluation form). The study sample consisted of sixty-nine patients who had sought treatment at one of two tertiary referral clinics because of problems related to the elbow. Pearson product-moment correlation coefficients were used to compare the raw aggregate scores, and kappa statistics were used to determine the level of agreement among the categorical rankings (excellent, good, fair, and poor). Examination of the five scoring systems revealed a remarkable lack of concordance with regard to the aspects of elbow function that were assessed. Good correlation was observed when the systems were compared on the basis of raw scores (Pearson product-moment correlation coefficients, 0.79 to 0.90), but only slight-to-moderate correlation was noted when the systems were compared on the basis of categorical rankings (quadratic weighted kappa coefficients, 0.18 to 0.49). Validity testing showed the system of Ewald et al. and the Mayo elbow-performance index to be the most discriminating, the system of Pritchard to be the least discriminating, and the system of The Hospital for Special Surgery and the system of Broberg and Morrey to be intermediate. The scores determined with the elbow-scoring systems demonstrated only moderate correlation with the score for function on the visual analog scale (Pearson product-moment correlation coefficients, 0.44 to 0.66), whereas those derived from the functional questionnaires completed by the patient demonstrated moderate-to-good correlation with the score for function (Pearson product-moment correlation coefficients, 0.72 and 0.80).

Pulmonary effects of fixation of a fracture with a plate compared with intramedullary nailing. A canine model of fat embolism and fracture fixation.

UNLABELLED: Fat-embolism syndrome and pulmonary dysfunction may develop in multiply injured patients who have a fracture of a long bone. Although early fixation of a fracture is beneficial, intramedullary nailing may exacerbate pulmonary dysfunction by causing additional embolization of marrow fat. We examined the pulmonary effects of the timing and method of fixation of a fracture in a canine fat-embolism model. Fat embolism was induced in forty-one adult dogs by reaming the ipsilateral femur and tibia followed by pressurization of the intramedullary canal. The animals were divided into a control group of eight dogs that had induction of fat embolism alone and an experimental group of thirty-three dogs that had induction of fat embolism and internal fixation of a transverse fracture of the middle of the contralateral femoral shaft. In the control group, four dogs each were killed four hours and twenty-four hours after induction of fat embolism. In the experimental group, a femoral fracture was created and fixation was performed four hours after embolic showering in fifteen animals and twenty-four hours after embolization in eighteen animals. The two experimental groups were subdivided according to the method of fixation of the fracture: eleven dogs each had application of a plate, nailing without reaming, and nailing with reaming. The pulmonary arterial pressure and the alveolar-arterial gradient were measured preoperatively, during induction of fat embolism, and as long as one hour after fixation of the fracture but before the animal was killed. The lungs, brain, and kidneys were examined for pathological and physiological evidence of intravascular fat. The intravascular fat persisted for twenty-four hours after induction of pulmonary fat embolism. Pulmonary arterial pressure remained elevated at four hours after the embolic showering, before creation and fixation of the fracture. By twenty-four hours after the induction of fat embolism, pulmonary arterial pressure had returned to the baseline level. Neither the creation nor the fixation of the fracture affected pulmonary arterial pressure. In the animals that had fixation of a fracture four hours after embolization, both nailing with reaming and nailing without reaming produced alveolar-arterial gradients that were higher than the baseline values, whereas fixation with a plate did not change the alveolar-arterial gradient significantly from the baseline value. In addition, the alveolar-arterial gradients in the animals that had nailing with reaming and nailing without reaming four hours after embolization were, respectively, four and 3.5 times higher than that in the animals that had fixation of the femur with a plate. In the animals that had fixation twenty-four hours after embolization, none of the methods for fixation affected the alveolar-arterial gradient. The amount of embolic fat in the lungs, brain, and kidneys was not affected by fixation of the fracture when it was performed at either the four-hour or the twenty-four-hour time-interval. Scores for pulmonary edema were increased by fixation of the fracture, but there was no difference among the scores associated with the three methods of fixation. CLINICAL RELEVANCE: The findings of the present study indicated that the amount of intravascular fat persisting in the lungs, kidneys, and brain twenty-four hours after pressurization of the intramedullary canal is not affected by the method of fixation of the fracture. Fixation of a fracture is associated with minimum evidence of acute inflammation and has no effect on pulmonary artery pressure. The development of pulmonary dysfunction from fat emboli depends on other factors, not just on the presence of fat in pulmonary vessels. It appears that the method of fracture fixation has little influence on the outcome of treatment.