Radiographic Evaluation of the Tibial Intramedullary Nail Entry Point

A novel assisted reduction method in extra-articular fractures of the distal tibia treated with intramedullary nail

Background

To explore the clinical efficacy and safety of Kirschner wires (KWs) as a blocking screw technique for extra-articular fractures of the distal tibia treated with intramedullary nails (IMNs).

Methods

Fifty-three patients were treated with KW-assisted IMN for extra-articular fractures of the distal tibia via the blocking screw technique or Poller screw (PS) technique. The operation time, number of fluoroscopies, number of blocking screws used, blood loss and time to union were compared between the two groups. Additionally, the functional outcomes of the two groups were compared using range of motion (ROM), visual analog scale (VAS), American Orthopedic Foot and Ankle Society (AOFAS), and Lysholm scores.

Results

Compared with those in the PS group, the operation time in the KW group was significantly shorter, and the number of fluoroscopy procedures and amount of blood loss during KW surgery were also significantly lower (p = 0.014, 0.001, and 0.036, respectively). Regarding the functional outcomes, there were no significant differences in the ROM, VAS score, AOFAS score or Lysholm score between the two groups (p > 0.05).

Conclusion

In the treatment of extra-articular fractures of the distal tibia with nails, the use of KW as a blocking screw technique is safe and reliable.

Does the distal nail position impact the rates of misalignment and bone union in distal tibial fractures?

PURPOSE

This retrospective study aimed to assess the impact of distal nail placement on misalignment and healing rates in distal tibial fractures.

METHODS

We reviewed all patients with distal tibial fracture treated with intramedullary nailing between 2015 and 2021, and a minimum follow-up of 12 months. Distal nail positioning was determined according to the Triantafillou zones. We related these positioning zones to misalignments (alignment ≥ 3°) and too bony union disorders (delayed union, non-union).

RESULTS

Out of the 62 patients included, 56 (90.3%) show bone union without additional procedure, 3 (4.8%) with dynamization, and 3 (4.8%) showed non-union. Twenty-one (33.8%) presented misalignment, with valgus in the coronal plane being the most frequent (76.19%). In patients with and without misalignment, the most frequent distal nail position was 2-2 in 47.6% and 80.5%, respectively (p = 0.01). In multivariate analysis, distal nail positioning in the 2-2 zone showed a significant protective effect against misalignment (OR 0.18; p = 0.018), while nail positioning in the 3-2 zone generated a significant risk of misalignment (OR 18.55; p = 0.009).

CONCLUSION

In intramedullary nailing of distal tibial fractures, distal positioning of the nail slightly lateral to the center of the talus in the coronal plane and slightly posterior in the sagittal plane (zone 2-2) allows high alignment percentages to be obtained. Positioning medial to this point in the coronal plane (zone 3) is associated with more significant misalignment and should be avoided.

Ideal entry point and direction of retrograde intramedullary nailing of the tibia

PURPOSE

To determine the ideal entry point and direction of retrograde intramedullary nailing of the tibia.

METHODS

The imaging data of patients with distal tibial fractures from June 2020 to December 2021 in our hospital were collected, and computer-aided design was performed. The relevant data were imported into the software for processing, so as to obtain a distal tibial fracture model and simulate the retrograde intramedullary nail placement in the tibia. The entry points and angles at which the intramedullary nail could be inserted successfully and the fracture could be maintained in good alignment were overlapped and counted to obtain the safe entry range and angle. The center of this safe range is the ideal entry point for retrograde intramedullary nailing of the tibia, and the mean value of the angle is the ideal direction of entry.

RESULTS

The ideal entry point of the retrograde intramedullary nailing was located at the midpoint of the medial malleolus in the C-arm fluoroscopic anteroposterior (AP) and lateral view. The ideal nail entry direction was located at the anatomic axis of the medial malleolus in the AP position and at the anatomic axis of the distal tibial metaphysis in the lateral position.

CONCLUSION

The ideal point and direction of nail insertion for retrograde tibial intramedullary nailing is a "double midpoint, double axis" approach.

Native tibia valga: a potential source of varus malreduction during intramedullary tibial nail fixation of tibial shaft fractures

PURPOSE

To determine the effect of native tibia valga on intramedullary nail (IMN) fixation of tibial shaft fractures.

METHODS

Retrospective comparative cohort analysis of 110 consecutive patients with tibial shaft fractures undergoing IMN fixation at an urban level one trauma centre was performed. Medical records and radiographs were reviewed for demographics, tibia centre of rotation of angulation (CORA), nail starting point, incidence of varus malreduction, and nail/canal proportional fit.

RESULTS

Tibia valga (CORA of ≥ 3 degrees) was present in 37 (33.6%) patients. The anatomic nail starting point distance (in relation to the lateral tibial spine) was significantly greater in the tibia valga group (12.0 mm vs. 5.0 mm, mean difference: 7.1 mm, 95% CI: 5.8 to 8.3 mm, p < 0.0001). Varus malreduction was more common in the tibia valga group (10.8% vs. 1.4%, proportional difference: 9.4%, 95% CI: - 1.0 to 21.3%, p = 0.04). Varus malreduction in the tibia valga group was associated with a decreased nail width/inner canal width proportion on multivariate analysis (OR = 0.683, 95% CI: 0.468 to 0.995, p = 0.0004).

CONCLUSION

Native tibia valga is common, and the use of a standard coronal IMN starting point with poor nail fit can lead to iatrogenic varus malreduction. In patients with tibia valga, maximizing nail fit or utilization of a medial starting point should be considered.

Suprapatellar versus infrapatellar approach for intramedullary nail fixation of tibial shaft fractures: a review of the literature

Semi-extended suprapatellar intramedullary nail fixation of tibial fractures has recently been gaining popularity. Several recent studies and meta-analyses compare the outcomes of the suprapatellar approach with the traditional infrapatellar approach. Despite concerns with intra-articular placement of instruments, studies show the suprapatellar approach to be a safe alternative. Several articles conclude that the suprapatellar approach may be superior to the infrapatellar approach. This review discusses recent findings comparing suprapatellar and infrapatellar approaches for nail insertion.

Evaluation of anatomical axis-joint center distance and anatomical axis-joint center ratio in distal femur and proximal tibia in coronal plane of Indian population

BACKGROUND

Radiographic evaluation of the anatomical geometry of the bone is important for executing reconstructive surgeries like deformity correction, limb lengthening and joint replacements. Various studies have been done in the past to define the anatomic placement of implant inside the bone. The aim of this study is to evaluate the distance between the anatomical axis and joint center of the distal femur (aJCD-f) and proximal tibia (aJCD-t) along with the ratio of anatomical axis-joint center distance of distal femur (aJCR-f) and proximal tibia (aJCR-t) of the skeletally mature individual of Indian population along with its application in day to day practice.

METHODS

Data is procured from the standard radiographs of the knee on large films. The anatomical axis is drawn on both sides of tibia and femur in a standard fashion. These lines intersect the horizontal drawn line at the intercondylar notch of femur and joint orientation line of the tibia. The aJCD-f, aJCD-t, aJCR-f, aJCR-t are then measured. Also the center of the inter-spinous distance of the tibia is measured from the anatomical axis (aSCD-t).

RESULTS

A total of 182 x-rays of skeletally mature individual were included with mean age of 46.35 ± 13.93 years. Of them 81 were males and 101 were females. There were 89 x-ray of left side and 93 x-ray of right side. The mean width of the femur at the intercondylar notch is found to be 76.78 mm (±7.40). The mean aJCD-f is found to be 3.87 mm (±2.44), aJCR-f to be 0.50 (±0.06). The mean width of the tibia is found to be 76.80 mm (±6.48). The aJCD-t is found to be 2.20 mm (±1.41), aJCR-t to be 0.50 (±0.03). The aSCD-t at the level of tibial spine is found to be -0.23 mm (±2.84). There was significant difference in the width of the femoral condyle of males 82.13 mm (±0.65) and females 72.48 mm (±0.55). Males showed mean aJCD-f of 3.59 mm (±2.42) and females showed 4.10 mm (±2.46). The aJCR-f is found to be significantly different between males 0.49 (±0.05) and females 0.51 (±0.07). There is significant difference between the width of the proximal tibia between males 80.83 mm (±0.68) and females 73.56 mm (±0.46). The aJCD-t of males and females is found to be 2.28 mm (±1.25) and 2.16 mm (±1.54) respectively. The aJCR-t is found to be significantly different between males 0.49 (±0.03) and females 0.50 (±0.04). While the mean distance of the anatomical axis from the lateral tibial spine is 0.23 mm lateral to the center of the inter-spinous distance and is found to be same in both males and females -0.23 mm (±2.84).

CONCLUSION

The coronal plane parameter like aJCD, aJCR of femur and tibia and aSCD-t of tibia can be a useful parameter to calculate in the 'real world' settings for reconstructive surgeries like deformity correction, nailing through the knee for femur and tibia as well as replacement surgeries around knee.