Dissertation committee:
Βασιλειάδης Ηλίας, Επίκουρος Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Πνευματικός Σπυρίδων, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Βλάμης Ιωάννης, Αναπληρωτής Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Χρονόπουλος Ευστάθιος, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Νικολάου Βασίλειος, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Κουλουβάρης Παναγιώτης, Αναπληρωτής Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Ευαγγελόπουλος Δημήτριος, Επίκουρος Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Summary:
Background and Objectives: Intertrochanteric fractures of the proximal femur constitute one of the most common causes of attendance at the orthopedic emergency department and are a significant factor in the morbidity and mortality of elderly patients. The treatment of these fractures is usually surgical, with closed reduction and internal fixation, with the patient placed on a traction table. The quality of the intraoperative reduction is considered particularly important for both the fracture healing and the functional outcome. Rotational deformity during intramedullary nailing of an intertrochanteric fracture constitutes the most difficult complication to detect, since intraoperative radiographic imaging enables the assessment of the quality of reduction in the frontal and sagittal planes, but not in the transverse plane. The purpose of this study is to evaluate the rotational malalignment of intertrochanteric fractures treated with intramedullary fixation and to investigate its effects on patient’s functional outcome and overall health status.
Materials and Methods: 74 patients with an intertrochanteric fracture of the proximal femur, who met the inclusion criteria, were included in the present study, after providing a written consent. All of them were treated surgically with intramedullary nailing, by the same surgeon team and by using the same implant. Fracture type was categorized, according to the AO/OTA classification, on the preoperative pelvis-hip radiograph, while rotational alignment was calculated through measurements on a postoperative hip-knee CT scan. The value of the femoral anteversion was calculated on both the operated (angle 1) and the healthy hip (angle 2), based on the technique described by Jeanmart et al., as well as the postoperative difference of anteversion (angle D) between the two hips. A D angle with a positive value indicated the presence of internal rotational overcorrection during reduction, while a D angle with a negative value indicated the presence of external rotational overcorrection. The absolute value of the D angle represented the difference in femoral anteversion between the operated and healthy hip. Based on this, patients were divided into 3 groups: group A (D ≤ 5°) – normal anteversion difference, group B (5° < D < 15°) – acceptable rotational alignment, group C (D ≥ 15°) – rotational deformity. During the postoperative period, each patient was re-evaluated at 6 and 12 months, with a pelvis-hips X-ray in order to assess the fracture union, and through clinical examination in order to evaluate their functional outcome and their overall health status. For a better interpretation of the functional outcome, the modified Harris Hip Score evaluation system was used, validated in the Greek language.
Results: The measurements on the CT scan were performed twice by the principal investigator and once more by an independent observer, with the intraobserver reliability calculated at 1,6° and the interobserver reliability calculated at 1,9°. Out of the 74 cases recorded, 28 (37.8%) accounted for stable fractures, 35 (47.3%) accounted for unstable fractures, and 11 (14.9%) accounted for reverse oblique fractures. Regarding the femoral anteversion difference, 42 cases (56.7%) presented a difference of less than or equal to 5° and were assigned to group A, 9 cases (12.2%) presented a difference of more than 5° to less than 15° and were assigned to group B, while 23 cases (31.1%) presented a difference greater than or equal to 15° and were assigned to group C. For group A, the mean femoral anteversion difference was 2.6° with a standard deviation of 1.4° (range 0.9° to 4.9°), group B had a mean value of 9.6° with a standard deviation of 2.2° (range 5.2° to 14.8°), while group C had a mean value of 22.5° with a standard deviation of 6.1° (range 15° to 48.5°). Out of the 74 patients, 59 (79.7%) presented with an internal rotational overcorrection (positive D angle) with a mean value of 43° and a standard deviation of 33.3°, while the remaining 15 patients (20.3%) presented with an external rotational overcorrection (negative D angle) with a mean value of -21.3° and a standard deviation of 18.6°. Specifically, in group A, 32 patients (76.2%) presented with a positive D angle value and the remaining 10 (23.8%) presented with a negative value. In group B, 6 patients (66.7%) presented with a positive D angle value, while 3 (33.3%) presented with a negative value. In group C, 21 patients (91.3%) presented with a positive D angle value, with the remaining 2 (8.7%) presenting with a negative value. Our statistical analysis did not reveal a relationship between the femoral anteversion difference and the internal/external rotational overcorrection during fracture reduction (p-value > 0.05). Meanwhile, a relationship was observed (p-value = 0.029) between the fracture type (classified by AO/OTA) and the difference in femoral anteversion, with stable fractures usually presenting a lower difference compared to unstable and reverse oblique fractures. Regarding the functional outcome six months postoperatively, the group of patients presenting with an acceptable femoral anteversion difference (D < 15°), in a total of 49 cases, showed a mean prefracture-postoperative mHHS difference value of 8.7/100 with a standard deviation of 6.1, while the group of patients with rotational deformity (D ≥ 15°) showed a mean prefracture-postoperative mHHS difference value of 14.5/100 with a standard deviation of 12.4, in a total of 18 cases. The analysis of these results reveals a statistical significance (t = -2.536, significance < 0.05), with the patients presenting a rotational deformity falling short of their baseline functional level, in comparison to the other group of patients, after the first six months postoperatively. As for the functional level one year postoperatively, the group of patients presenting with an acceptable femoral anteversion difference (D < 15°), in a total of 47 cases, presented a mean prefracture-postoperative mHHS difference value of 4.9/100 with a standard deviation of 7.8, while the group of patients with rotational deformity (D ≥ 15°) presented a mean prefracture-postoperative mHHS difference value of 8.3/100 with a standard deviation of 13, in a total of 16 cases. Analysis of these results did not reveal a statistical significance (t = -1.266, significance > 0.05), with most patients approaching their baseline functional level, regardless of the rotational alignment, after the first postoperative year. Regarding the presence of fracture union at six months postoperatively, 65 cases (97.0%) showed radiographic union, while 2 (3%) resulted in non-union. In group A, fracture union was observed in 39 cases (97.5%), while 1 case (2.5%) resulted in non-union. In group B, all cases showed radiographic union (100%). In group C, 17 cases (94.4%) presented with fracture union and 1 case (5.6%) proceeded to non-union. Statistical analysis of these results did not reveal a relationship (p-value > 0.05) between the difference in femoral anteversion and fracture union. Six months postoperatively, out of the 74 patients recorded, 67 (90.5%) survived and 7 (9.5%) died. In group A, out of 42 patients, 40 (95.2%) survived and 2 (4.8%) died. In group B, all 9 patients survived (100%). In group C, out of the 23 patients, 18 (78.3%) survived and 5 (21.7%) died. Analysis of these results revealed a statistically significant relationship (p-value = 0.048) between the difference in femoral anteversion and the six-month mortality. One year postoperatively, out of the 74 patients recorded, 63 (85.1%) survived and 11 (14.9%) died. In group A, out of the 42 cases, 38 (90.5%) survived and 4 (9.5%) survived. In group B, all 9 cases survived (100%). In group C, out of the 23 cases, 16 (69.6%) survived and 7 (30.4%) died. Analysis of these results revealed a statistically significant relationship (p-value = 0.031) between the difference in femoral anteversion and one-year mortality.
Conclusions: Rotational deformity after intramedullary nailing of intertrochanteric fractures is a frequent complication, which is quite difficult to avoid through the typical intraoperative radiologic evaluation. Therefore, the use of more accurate intraoperative methods (radiological protocols, 3D imaging, computer-assisted tomography) is deemed necessary to avoid this kind of complication. Regarding the effects of rotational deformity on the patients' functional level, our results showed that its impact mainly concerns the first six months postoperatively, while it tends to be eliminated by reaching one year postoperatively. Additionally, rotational deformity does not show an impact on fracture union, nor any relation with other postoperative complications. On the contrary, the mortality of these patients shows a correlation with the presence of rotational deformity, both at six months and one year postoperatively. Of course, it is deemed necessary to create a more accurate system for assessing the functional level in the elderly and to use it on a larger population group to confirm the above-mentioned results.
