ObjectiveTo review the research progress on correction of severe foot and ankle deformities with digital hexapod external fixators. Methods The relevant research literature on digital hexapod external fixators at home and abroad in recent years was reviewed and analyzed. Taking Taylor spatial frame (TSF) as a representative, this article elaborates on the research progress of this technology in the treatment of severe foot and ankle deformities from aspects such as device principle, technical characteristics, clinical application, complication management, and controversial perspectives, aiming to provide theoretical references for clinical application. Results The treatment of severe foot and ankle deformities is a complex challenge in orthopedics, often involving multiple plane alignment abnormalities, muscle weakness, soft tissue contractures, and joint dysfunction. The digital hexapod external fixators (such as TSF), based on the principle of six degrees of freedom motion and combined with computer-assisted technology, enables precise correction of multi-dimensional deformities. Conclusion The digital hexapod external fixators provides a minimally invasive and efficient option for the treatment of severe foot and ankle deformities, and shows significant advantages in the treatment of complex post-traumatic deformities, neuromuscular deformities, diabetes Charcot arthropathy, and other diseases.
A series of 28 cases of fractures of the small tubular bones of the hand, including Bennetts fracture, were treated with the minor unilateral multifunctional external fixator. After manipulation, a hole was drilled on the proximal and distal parts of the fractured bone. Hand in functional position, the external fixator was set in place. Functional exercises were begun after the fixation. The patients were follwed up for two to six months. The average healing time was thirtyfive days. The average healing time for Bennett’s fractures was twentyeight days, and for the fractures of metacarpal bone was forty-two days. There were no deformity and complication of infection following external fixation.The functional recovery of the hands was satisfactory. The fixator had the following advantages: It was simple and had tight fixation; fractures with infection, was still indicated and could be adjusted according to the clinical purpose.
Objective To investigate the effectiveness of single Taylor external fixator combined with biplanar osteotomy on correction of tibial multiplanar deformities. Methods Between October 2016 and December 2021, 11 patients with tibial multiplanar deformities (20 sides) were treated with single Taylor external fixator and biplanar osteotomy. Of them, 4 were male and 7 were female; the average age ranged from 13 to 33 years (mean, 21.9 years). Diagnosis included rickets severe genu varum deformity (7 cases, 14 sides), rickets severe genu valgum deformity (2 cases, 4 sides), multiple osteochondromatosis calf deformity (1 case, 1 side), neurofibromatosis medial lower leg anterior arch deformity with short of leg (1 case, 1 side). After fibular osteotomy and tibial multiplanar osteotomy, a Taylor external fixator was installed. After operation, the deformities were corrected successively and fixed completely. The osteotomy healed, then the external fixator was removed. Before operation and at 12 months after operation, the full-length X-ray films were taken. The leg-length discrepancy, medial proximal tibial angle (MPTA), lateral distal tibial angle (LDTA), posterior proximal tibial angle (PPTA), anterior distal tibial angle (ADTA), and tibial rotation angle were measured. The degree of lower limb deformity was scored with reference to a customized tibial mechanical axis scoring table. Results Osteotomy was successfully completed without neurovascular injury and other complications. The external fixator was adjusted for 28-46 days, with an average of 37 days, and the external fixator was worn for 136-292 days, with an average of 169 days. Mild needle infection during the fixation period occurred in 3 sides, refracture at the distal tibial osteotomy in 1 side after removing the external fixator, and nonunion of the distal fibular osteotomy in 1 side. All patients were followed up 369-397 days (mean, 375 days). At 12 months after operation, the lower limb discrepancy decreased, but there was no significant difference (P>0.05). MPTA, LDTA, PPTA, ADTA, and tibial rotation angle improved, and the differences in LDTA, ADTA, and tibial rotation angle were significant (P<0.05). The score of lower limb deformity was significantly higher than that before operation (P<0.05), and the results were excellent in 9 sides, good in 8 sides, fair in 3 sides, with the excellent and good rate of 85%. ConclusionSingle Taylor external fixator combined with biplanar osteotomy is effective in the correction of tibial multiplanar deformities.
ObjectiveTo compare the effectiveness of Taylor spatial frame (TSF) and unilateral external fixator in the treatment of tibiofibular open fractures.MethodsBetween 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.ResultsAll 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).ConclusionFor 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.
Objective To investigate the mid- and long-term effectiveness of external fixator distraction arthroplasty in the treatment of moderate to severe ankle arthritis. Methods The clinical data of 23 patients with moderate to severe ankle arthritis treated with external fixation distraction arthroplasty who met the selection criteria between January 2007 and November 2019 were retrospectively analyzed. There were 20 males and 3 females; the age ranged from 21 to 65 years, with an average age of 43.7 years. Etiology included 8 cases of primary ankle arthritis, in which 5 cases combined with varus deformity; 15 cases of traumatic ankle arthritis, the cause of injury was 5 cases after ankle fracture surgery, 3 cases after Pilon fracture surgery, 5 cases of chronic ankle instability and repeated sprain, and 2 cases of other causes. According to Takakura staging system, there were 4 cases of stage ⅢA, 12 cases of stage ⅢB, and 7 cases of stage Ⅳ; according to Giannini staging system, there were 5 cases of stage Ⅱ and 18 cases of stage Ⅲ; according to Cheng staging system, 16 cases were in stage Ⅲ, and 7 cases stage Ⅳ. American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and visual analogue scale (VAS) score were used to evaluate the improvement of ankle pain and function before operation and at last follow-up, and the data were analyzed according to different etiological groups. At last follow-up, the surgical results were evaluated subjectively and objectively. The changes of ankle joint space before operation and at last follow-up were compared. The patients were divided into two groups according to their age: ≤45 years old group [young group, 10 cases, aged (35.62±7.41) years old] and >45 years old group [middle-aged and elderly group, 13 cases, aged (54.20±6.20) years old]. The AOFAS ankle-hindfoot score and VAS score were compared before and after operation between the two groups, and the influence of age on distraction arthroplasty was analyzed. ResultsThe external fixator was removed after 3 months of continuous distraction,12 patients got infection around the wire tunnels. All the 23 patients were followed up 13-143 months, with an average of 56.9 months; the follow-up time was (43.46±32.77) months and (69.80±37.79) months in the young group and middle-aged and elderly group, respectively. At last follow-up, the AOFAS ankle-hindfoot score and VAS score significantly improved when compared with those before operation (P<0.05). According to etiological analysis, there was no significant difference in AOFAS ankle-hindfoot score and VAS score before and after operation (P>0.05) in Pilon fracture patients, while the significant difference was found in remaining patients (P<0.05). There was significant difference in AOFAS ankle-hindfoot score before operation between the young group and the middle-aged and elderly group (t=2.110, P=0.040), but no significant difference in preoperative VAS score and the differences in VAS score and AOFAS ankle-hindfoot score before and after operation between the two groups (P>0.05). The subjective and objective results of pain evaluation at last follow-up showed that 4 patients had no pain, 12 patients had moderate pain relief, 5 patients had mild pain relief, and 2 patients had no significant pain relief; among the 10 patients who were followed up more than 5 years, there were 2, 5, 2, and 1 patient, respectively; 2 patients who were followed up more than 10 years had moderate pain relief. At last follow-up, the ankle joint space was (3.7±0.4) mm, which significantly increased when compared with before operation [(1.5±0.2) mm] (t=1.791, P=0.002). The ankle joint space was (2.9±0.5) mm in 10 patients who were followed up more than 5 years, and 3.3 mm and 3.0 mm in 2 patients who were followed up more than 10 years. Conclusion Distraction arthroplasty of the ankle joint can achieve satisfactory results in patients with moderate to severe ankle arthritis (except for arthritis caused by Pilon fracture), and age has no significant effect on distraction arthroplasty.
Objective
To compare the effectiveness of suspension fixation plus hinged external fixator with double plate internal fixation in the treatment of type C humeral intercondylar fractures.
Methods
Between January 2014 and April 2016, 30 patients with type C (Association for the Study of Internal Fixation, AO/ASIF) humeral intercondylar fractures were treated. Kirschner wire suspension fixation plus hinged external fixator was used in 14 cases (group A), and double plate internal fixation in 16 cases (group B). There was no significant difference in gender, age, injury cause, disease duration, injury side, and type of fracture between 2 groups (P>0.05).
Results
There was no significant difference in operation time and hospitalization stay between 2 groups (P>0.05). But the intraoperative blood loss in group A was significantly less than that in group B (P<0.05); the visual analogue scale (VAS) score at 1 day and 3 days after operation in group A were significantly less than those in group B (P<0.05). Primary healing of incision was obtained in all patients of 2 groups, and no surgery-related complications occurred. The patients were followed up 6-24 months (mean, 12.3 months) in group A and 6-24 months (mean, 12.8 months) in group B. The self-evaluation satisfaction rate was 85.7% (12/14) in group A and was 81.2% (13/16) in group B at 3 months after operation, showing no significant difference (χ2=0.055, P=0.990). Based on the improved Gassebaum elbow performance score at 6 months after operation, excellent and good rate of the elbow function was 78.6% (excellent in 5 cases, good in 6 cases, fair in 2 cases, and poor in 1 case) in group A and was 81.2% (excellent in 6 cases, good in 7 cases, fair in 2 cases, and poor in 1 case) in group B, showing no significant difference between 2 groups (χ2=0.056, P=0.990). Heterotopic ossification occurred at 3 months after operation in 1 case of each group respectively. The X-ray films showed bony union in all cases; no loosening or breakage of screw was observed. The bone union time showed no significant difference between 2 groups (t=–0.028, P=0.978). The time of internal fixation removal, the intraoperative blood loss, and VAS score at 1 day and 3 days after operation in group A were significant better than those in group B (P<0.05).
Conclusion
The suspension fixation plus hinged external fixator and double plate internal fixation for the treatment of type C humeral intercondylar fractures have ideal outcome in elbow function. But the suspension fixation plus hinged external fixator is better than double plate internal fixation in intraoperative blood loss, postoperative VAS score, and time of internal fixation removal.
ObjectiveThe anatomical calcaneal external fixator was designed by measuring and calculating the morphological data of the heel.MethodsA total of 100 normal people were randomly selected to obtain 200 hind foot data, including 45 males and 55 females, with an average age of 43.9 years (range, 19-67 years). According to the principles of human engineering and local anatomy, the morphological data of the heel in the weight-bearing standing position and supine position were measured with the direct measurement mode. The heel length, heel width, heel height, medial ankle height, lateral ankle height, and calcaneal pitch angle (CPA) were measured by vernier calipers and ulnar markers in weight-bearing standing position, and the gender groups and left and right foot groups were compared; the shape of the hind foot in the supine position was measured by three-dimensional (3D) dot matrix inverse model method. According to the stereoscopic data of the comprehensive anatomical morphology of the heel, the anatomical calcaneal external fixator was designed with AutoCAD 2019 and other 3D industrial design softwares.ResultsThe measurements of shoe size, heel length, heel width, heel height, medial ankle height, lateral ankle height, and CPA in male were significantly higher than those in female (P<0.05). There was no significant difference between the left and right feet in the other indexes except that the height of the medial malleolus of the left foot was significantly lower than that of the right foot (t=?2.827, P=0.005). The measurement of 3D dot matrix inverse model in supine position showed that the heel part was non-circular arc edge, and many groups of arc edges fluctuate in a limited range. Based on the above data, an anatomical calcaneal external fixator was designed, which could fit the anatomic radian in theory, so as to be flexible in configuration. On this basis, the ordinary configuration, compression configuration, and orthodontic configuration were designed to meet the treatment needs of calcaneal fractures in different degrees. The ordinary configuration was suitable for patients with Sanders Ⅰ, ⅡA, and ⅡB calcaneal fractures with no or slight displacement of intra-articular fractures; the ordinary configuration was mainly used for simple fixing. The compression configuration was suitable for patients with Sanders ⅡC, ⅢA, and ⅢB, tongue fractures, and avulsion fractures with severe displacement of intra-articular fractures; the compression configuration used obliquely drawn console wires to fix the displaced bones. The orthodontic configuration was suitable for patients with Sanders ⅢC and Ⅳ calcaneal fractures with severe displacement of intra-articular fractures or severe calcaneal bone defects; the orthodontic configuration was a multi-module design, which took into account the stable fixation of the fracture and the arbitrary adjustment of the joint fixation angle.ConclusionThe hind foot is special for morphology, so the external fixator designed based on the vernier caliper measurement method and 3D dot matrix measuring plate measurement method is an anatomical type and its configuration can theoretically meet stable and flexible clinical needs.
Objective
To investigate the effectiveness of hinged external fixator with mini-plate to treat terrible triad of the elbow.
Methods
Between August 2008 and June 2011, 11 patients with terrible triad of the elbow were treated with hinged external fixator combined with mini-plate. There were 9 males and 2 females, aged 22-56 years (mean, 34 years). The injuries were caused by falling from height in 8 cases and traffic accident in 3 cases. All patients were closed injury. The time from injury to operation varied from 8 hours to 7 days (mean, 3.7 days). According to Mason classification standard, all radial head fractures were type IV and complicated by posterior dislocation of the elbow; according to Regan-Morrey classification standard, ulna coronary process fractures were type I in 3 cases, type II in 3 cases, and type III in 5 cases.
Results
All the patients achieved primary healing of incision after operation and no nerve injury occurred. The patients were followed up 12-20 months (mean, 15 months). Two cases had screw channel infection after 12 weeks of operation, and 1 case had mild heterotopic ossification of the elbow after 4 months of operation. X-ray films showed that all fractures healed from 8 to 20 weeks (mean, 16 weeks). No recurrent dislocation or instability of the elbow occurred. At 12 months after operation, the elbow range of motion (ROM) were 120-145° (mean, 135°) in flexion, 0-25° (mean, 10°) in extension, 50-90° (mean, 70°) in pronation, and 50-80° (mean, 60°) in supination. According to Mayo elbow function evaluation standard, the results were excellent in 5 cases, good in 4 cases, and fair in 2 cases, with an excellent and good rate of 81.8%.
Conclusion
Hinged external fixator with mini-plate can enhance postoperative stability of the elbow. This therapy is beneficial to early functional exercise and obviously decrease the disability rate caused by complex damage on the elbow.
To provide the scientific theoretical basis for cl inical practice by comparing biomechanicalcharacteristics of single compressed plate with intramedullary pin, locking intramedullary nail and simple arm externalfixator with simple internal fixation devices. Methods Eighteen wet humeral bone specimens of adult cadaver were madecompl icated fracture models of humeral shaft and divided into 3 groups according to fixation methods. Fracture was fixed by single compressed plate with intramedullary pin in plate group, by locking intramedullary nail in intramedullary nail group and by external fixator with simple internal fixation devices in external fixator group. The intensity and rigidity of compl icated fracture models of humeral shaft was measured in compress test and torsion test. Results In compress test, the maximum load in plate group (6 162.09 ± 521.06) N and in intramedullary nail group (6 738.32 ± 525.89) N was significantly larger than that in external fixator group (2 753.57 ± 185.59) N (P lt; 0.05); but there was no significant difference between plate group and intramedullary nail group (P gt; 0.05). Under 600 N physiological compress load, the rigidity was (171.69 ± 6.49) N/mm in plate group, (333.04 ± 36.85) N/mm in intramedullary nail group and (132.59 ± 2.93) N/mm in external fixator group; showing no significant difference between plate group and external fixator group (P gt; 0.05), and showing significant difference between intramedullary nail group and plate, external fixator groups (P lt; 0.05). In torsion test, the maximum torque in plate group (38.24 ± 7.08) Nm was significantly larger than those in intramedullary nail group (17.12 ± 5.73) Nm and external fixator group (20.26 ± 6.42) Nm (P lt; 0.05), but there was no significant difference between intramedullary nail group and external fixator group (P gt; 0.05). Under 0.80 Nm physiological torque, the rigidity was (16.36 ± 2.07) Ncm/° in plate group and (18.79 ± 2.62) Ncm/° in external fixator group, which was significantly larger than that in intramedullary nail group (11.45 ± 0.22) Ncm/° (P lt; 0.05); but there was no significant difference between plate group and external fixator group (P gt; 0.05). Conclusion Those fracture models fixed by single compressed plate with intramedullary pin have better compress and torsion intensity, they also have better torsion rigidity but less compress rigidity. Those fracture models fixed by locking intramedullary nail have better compress intensity but less torsion intensity, they also have better compress rigidity but less torsion rigidity. Those fracture models fixed by external fixator with simple internal fixation device have less compress and torsion intensity, they also have less compress rigidity but better torsion rigidity.
Objective To analyze the effectiveness comparison of external fixator combined with Kirschner wire fixation and Kirschner wire fixation in the treatment of cubitus varus deformity in children. Methods A retrospective case-control study was conducted to collect 36 children of postoperative supracondylar humerus fracture complicating cubitus varus deformity between January 2018 and July 2022. Among them, 17 cases were treated with distal humeral wedge osteotomy external fixation combined with Kirschner wire fixation (observation group), and 19 cases were treated with distal humeral wedge osteotomy and Kirschner wire fixation (control group). The baseline data including age, gender, deformity side, time from fracture to operation, carrying angle of the healthy side and preoperative carrying angle of the affected side, elbow flexion and extension range of motion, and lateral condylar prominence index (LCPI) showed no significant difference between the two groups (P>0.05). The operation time, hospitalization cost, healing time of osteotomy, postoperative complications, and the carrying angle, LCPI, and elbow flexion and extention range of motion were recorded and compared between the two groups. The elbow function was assessed by Oppenheim score at 3 months after operation and at last follow-up. Results The children in both groups were followed up 13-48 months, with an average of 26.7 months. There was 1 case of needle tract infection in the observation group and 2 cases in the control group, and no nerve injury occurred, the difference in the incidence of complication (5.88% vs 10.53%) between the two groups was not significant (χ2=0.502, P=0.593). There was no significant difference in the operation time and fracture healing time between the two groups (P>0.05); the hospitalization cost of the observation group was significantly higher than that of the control group (P<0.05). The Oppenheim score of the observation group was significantly better than that of the control group at 3 months after operation (P<0.05), but there was no significant difference in the Oppenheim score between the two groups at last follow-up (P>0.05). At last follow-up, the carrying angle of affected side significantly improved in both groups when compared with preoperative ones (P<0.05); the differences of the pre- and post-operative carrying angle of affected side and elbow flexion and extension range of motion showed no significant differences between the two groups (P>0.05), but the difference in pre- and post-operative LCPI of the observation group was significantly better than that of the control group (P<0.05). ConclusionExternal fixator combined with Kirschner wire fixation and Kirschner wire fixation both can achieve satisfactory correction of cubitus varus deformity in children, and the former can achieve better short-term functional recovery of elbow joint and reduce the incidence of humeral lateral condyle protrusion.
