[Correction of posttraumatic lower leg deformities using the Taylor Spatial Frame]

[Reconstruction of posttraumatic deformities and defects]

The reconstruction of posttraumatic defects of bone and soft tissue, as well as residual deformities of the bone is often a lengthy and complicated procedure. Multiple surgical interventions are necessary to reconstruct the affected extremity and restore its functionality. To achieve an optimal result it often takes months or years and requires great patience and compliance of the patient. This treatment should be carried out in centers with the appropriate instrumental and human resources. Since the pathologies are often complex with bony deformities or loss of bone, as well as infections and soft tissue defects, the treatment should be carried out by very experienced surgeons to successfully manage these complex reconstructions. This often requires interdisciplinary cooperation, especially with experienced plastic surgeons. A soft tissue reconstruction for better blood circulation in the exposed bony structures, as well as the bony defects themselves, can be reconstructed at the same time.

Correction of severe lower extremity deformity with digital hexapod external fixator based on CT data

Purpose

Our goal was to examine the therapeutic effect of a self-designed digital six-axis external fixator technique for the correction of severe lower extremity deformities.

Patients and methods

Between January 2017 and December 2020, our institution employed self-developed digital hexapod external fixator technology (QSF), based on CT data, to gradually correct 28 severe tibial deformities, and 15 femurs underwent osteotomy and internal fixation. The mean patient age was 32.6 ± 14.3 years, and the mean follow-up duration was 27.4 ± 16.1 months. We also recoded and analyzed the values of preoperative and final follow-up MAD, mFTA, MPTA, LLD, mLDFA, LEFS, KSS, and functional score.

Results

The QSF adjustment duration was 21.4 ± 10.8 days, and the healing duration of the tibial osteotomy site was 17.6 ± 7.0 weeks. The preoperative MAD, mFTA, and MPTA were 54.1 ± 26.2 mm, 167.7 ± 15.7°, and 75.2 ± 12.0°, respectively. At the last follow-up, the MAD was 8.2 ± 9.9 mm, mFTA was 177.6 ± 3.4°, and MPTA was 87.6 ± 2.4°. Based on these data, we achieved significant improvement post operation. The preoperative LLD and mLDFA values were 13.8 ± 18 mm and 83.7 ± 10.8°, respectively, and the values were 7.6 ± 7.6 mm and 87.8 ± 2.6°, respectively, at the last follow-up. This indicated no significant difference in these values before and after the operation. Finally, the LEFS, KSS, and functional scores improved from preoperative 51.6 ± 11.2, 68.5 ± 11.7, and 67.8 ± 11.2 to postoperative 72.3 ± 6.1, 92.9 ± 3.4, and 94.2 ± 6.3, respectively.

Conclusions

Based on our analyses, the QSF technique accurately corrected severe multiplanar tibial deformities in adults. When combined with femoral osteotomy, satisfactory lower extremity alignment was obtained while correcting for femoral deformity. This technology has the advantages of simple operation, reliable fixation, less trauma, and less complications.

Improving postoperative radiographs for the parameter measurement of hexapod external fixator using an additional foot ring

BACKGROUND

It is challenging to determine the orthogonality of radiographs in daily clinical practice. The purpose of this study was to show the usefulness of an additional foot ring which might determine the orthogonality of postoperative radiographs for the parameter measurement of hexapod external fixator.

METHODS

We retrospectively analyzed 81 consecutive trauma patients with tibial shaft fractures treated by the hexapod external fixator at our institution from September 2014 to July 2019. Starting in March 2016, the postoperative radiographs for parameter measurement were obtained under the control of an additional foot ring. The final data consisted of 47 patients in traditional radiographs (Group I) and 34 patients under the control of foot ring during the radiographic process (Group II). The demographic data, original postoperative deformities, residual deformities after final correction, number of repeated radiographs after the first postoperative radiographs, time to the satisfactory reduction achieved, and external fixation time in all patients were documented and analyzed. The Johner-Wruhs criteria were used for the final clinical outcomes evaluation at the last clinical visit.

RESULTS

Satisfactory reduction and bone union were achieved in all patients. There were no statistical significances between the two groups in the demographic data, original postoperative deformities, residual deformities after final correction, external fixation time, and the final clinical outcomes (P > 0.05). The mean number of repeated radiographs after the first radiographs (1.4 times) and mean time to the satisfactory reduction achieved (3.3 days) in patients with an additional foot ring used were all less than those without foot ring (2.4 times, 5.3 days) (P < 0.05).

CONCLUSIONS

The additional foot ring is a practical device to ensure the orthogonality of postoperative radiographs for the hexapod external fixator parameter measurement. Radiation exposure, duration of deformity correction, and cost for patients might be reduced due to the less repeated radiographs with the wrong position.

Management of high-energy tibial shaft fractures using the hexapod circular external fixator

Background

The hexapod external fixator (HEF) is increasingly used for high-energy tibial shaft fracture care as more general orthopedic surgeons are gaining expertise of this versatile device. The purpose of this study was to evaluate the clinical effectiveness of the HEF for definitive management in patients with high-energy tibial shaft fractures.

Methods

The study was conducted on 34 patients with tibial shaft fractures who were admitted or referred to our institution and consented to HEF treatment from Jan 2016 to June 2019, including 27 males and 7 females with a mean age of 39 years (range 18 to 65 years). Patients' clinical and radiological data, and the final clinical outcomes at a minimum of 12 months follow-up were collected and retrospectively analyzed. All complications were documented according to Paley’s classification. The clinical outcomes were evaluated using the Association for the Study and Application of the Method of Ilizarov criteria (ASAMI) at the last clinical visit.

Results

All patients remained in the HEF for a mean of 26 weeks (range 15 to 52 weeks) and acquired complete bone union. The satisfactory alignment was achieved in all patients, and all the patients were able to perform daily activities with no difficulty at the last clinical visit. Complications included pin tract infection (44%), delayed union (6%), nonunion (3%), and joint stiffness (3%). The ASAMI bony result was excellent in 31 patients and good in 3. The ASAMI functional result was excellent in 27 patients, good in 6, and fair in 1.

Conclusions

Definitive management using the hexapod external fixator is an alternative and effective method for high-energy tibial shaft fractures, including technical advantages of early trauma-control, the versatility of achieving excellent alignment, and the continuity of device until bone union.

Application of elliptic registration and three-dimensional reconstruction in the postoperative measurement of Taylor spatial frame parameters

BACKGROUND

The Taylor spatial frame offered the ability of simultaneous correction of the multidirectional deformities without the need to change the frame, and it was widely used for limb lengthening, deformity correction, and fracture reduction in recent years. There are still some inherent limitations that can affect the accuracy of correction, especially for the measurement of the mounting and rotational parameters. The purpose of our study was to propose some more precise postoperative measurement of Taylor spatial frame (TSF) parameters by application of elliptic registration and three-dimensional reconstruction.

METHODS

This retrospectively study included 28 trauma patients who suffered tibial fracture treated by the TSF at our institution from January 2016 to January 2018, including 25 males and 3 females with a mean age of 43 years (range 14-70 years). We conducted standard full-length anteroposterior and lateral X-rays of the injured extremity and the computed tomographic scans of the bilateral extremities after the operation. Elliptic registration and 3D reconstruction were used to calculate the parameters by two types of software Mimics and CorelDRAW. Correction of the deformity was conducted by adjusting the struts of the TSF according to the electronic prescription. The standard anteroposterior and lateral X-rays after correction were taken to evaluate the effectiveness.

RESULTS

All patients acquired functional reduction, which was evaluated by digital radiography. The mean coronal plane translation(1.9±2.2 mm), coronal plane angulation(1.2±1.0°), sagittal plane translation(2.7±2.1 mm), and sagittal plane angulation(1.2±1.0°) after correction were all less than those(5.5±4.6 mm, 4.9±3.9°, 4.7±4.0 mm, 2.7±2.3°) before correction.

CONCLUSIONS

The TSF system can correct the 6-axis deformities simultaneously with the accurate parameters. Elliptic registration and three-dimensional reconstruction are alternative methods to precisely measure the parameters needed by the TSF system, especially for the mounting and rotational parameters of unusually complex cases.

[A comparative study of Taylor spatial frame and unilateral external fixator in treatment of tibiofibular open fractures]

Objective

To compare the effectiveness of Taylor spatial frame (TSF) and unilateral external fixator in the treatment of tibiofibular open fractures.

Methods

Between January 2016 and July 2018, 74 patients with tibiofibular open fracture who met the selection criteria were divided into TSF group (43 cases, fixed with TSF) and unilateral group (31 cases, fixed with unilateral external fixator) according to the principle of entering the group every other day. There was no significant difference in gender, age, affected side, cause of injury, type of fracture between the two groups ( P>0.05). The operation time, fracture healing time, removal time of external fixator, and complications were recorded and compared between the two groups. The limb function was evaluated according to Johner-Wruhs criteria for evaluating the final effectiveness of tibial shaft fracture treatment. The recovery of lower limb force line was ecaluated by LUO Congfeng et al. criteria.

Results

All patients were followed up 8-22 months, with a median of 12 months. All fractures healed, and no complication such as delayed union, nonunion, or osteomyelitis occurred. The operation time, fracture healing time, and removal time of external fixator in TSF group were significantly shorter than those in unilateral group ( P<0.05). At 3 months after the removal of the external fixator, the limb function was evaluated according to the Johner-Wruhs standard. In TSF group, 41 cases were excellent, 1 case was good, and 1 case was fair, and the excellent and good rate was 97.67%; in unilateral group, 30 cases were excellent and 1 case was fair, and the excellent and good rate was 96.77%; there was no significant difference between the two groups ( P=0.666). At 4 months after operation, the recovery of lower limb force line was ecaluated by LUO Congfeng et al. criterion. In TSF group, 41 cases were excellent, 2 cases were good, and 1 case was fair, and the excellent and good rate was 97.67%; in unilateral group, 29 cases were excellent, 1 case was good, 1 case was fair, and the excellent and good rate was 96.77%; there was no significant difference between the two groups ( P=0.666).

Conclusion

For tibiofibular open fracture, on the premise of fracture healing, TSF technology is superior to unilateral external fixation in terms of shortening operation time, fracture healing time, and removal time of external fixator.