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.
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.
Objective To summarize the methods of ankle hinge position design in the correction of clubfoot deformity by Ilizarov method, and to explore its application value in the prevention of ankle dislocation. Methods A retrospective study was conducted including 28 patients with rigid clubfoot deformity (34 feet) who met the selection criteria and admitted between September 2021 and December 2024. There were 19 males and 9 females with an average age of 31.8 years (range, 19-47 years). According to Dimeglio classification, there were 21 feet of degree Ⅲ and 13 feet of degree Ⅳ. The causes were traumatic sequelae in 9 cases, congenital foot deformity in 15 cases, spina bifida sequelae in 1 case, peripheral neuropathy in 1 case, and cerebral palsy sequelae in 2 cases. The malformation lasted from 6 to 46 years, with an average of 29.3 years. All patients were treated with Ilizarov circular external fixator, and the hinge position of ankle joint was planned according to the standard lateral X-ray film of foot and ankle and the principle of Ilizarov limb deformity correction center of rotation angulation (CORA) before operation. The 2008 International Clubfoot Study Group (ICFSG) scoring system was used to evaluate the efficacy. ResultsThe deformity of rigid clubfoot was completely corrected in all patients, and the patients could walk with plantar weight-bearing, and the ankle weight-bearing walking significantly improved when compared with that before operation. There was no complication such as ankle dislocation, talus impact or extrusion, local skin necrosis, needle tract infection, or numbness of extremities during the correction process. All patients were followed up 5-39 months, with an average of 18.1 months. At last follow-up, according to the ICFSG scoring system, 23 feet were excellent, 10 feet were good, and 1 foot was fair, and the excellent and good rate was 97%. Conclusion Designing the position of the ankle hinge according to the principle of CORA can effectively avoid ankle dislocation, talus impingement, tibiotalar joint extrusion, and other ankle adverse events in the process of correcting clubfoot deformity, which has good application value in clinical practice.
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.
Objective To evaluate the effectiveness of limited internal fixation combined with a hinged external fixator in the treatment of peri-elbow bone infection. Methods The clinical data of 19 patients with peri-elbow bone infection treated with limited internal fixation combined with a hinged external fixator between May 2018 and May 2021 were retrospectively analyzed. There were 15 males and 4 females with an average age of 44.6 years (range, 28-61 years). There were 13 cases of distal humerus fractures and 6 cases of proximal ulna fractures. All the 19 cases were infected after internal fixation of fracture, and 2 cases were complicated with radial nerve injury. According to Cierny-Mader anatomical classification, 11 cases were type Ⅱ, 6 cases were type Ⅲ, and 2 cases were type Ⅳ. The duration of bone infection was 1-3 years. After primary debridement, the bone defect was (3.04±0.28) cm, and the antibiotic bone cement was implanted into the defect area, and the external fixator was installed; 3 cases were repaired with latissimus dorsi myocutaneous flap, and 2 cases were repaired with lateral brachial fascial flap. Bone defects repair and reconstruction were performed after 6-8 weeks of infection control. The wound healing was observed, and white blood cell (WBC), erythrocyte sedimentation rate (ESR), and C-reaction protein (CRP) were reexamined regularly after operation to evaluate the infection control. X-ray films of the affected limb were taken regularly after operation to observe the bone healing in the defect area. At last follow-up, the flexion and extension range of motion and the total range of motion of the elbow joint were observed and recorded, and compared with those before operation, and the function of the elbow joint was evaluated by Mayo score. Results All patients were followed up 12-34 months (mean, 26.2 months). The wounds healed in 5 cases after skin flap repair. Two cases of recurrent infection were effectively controlled by debridement again and replacement of antibiotic bone cement. The infection control rate was 89.47% (17/19) in the first stage. Two patients with radial nerve injury had poor muscle strength of the affected limb, and the muscle strength of the affected limb recovered from grade Ⅲ to about grade Ⅳ after rehabilitation exercise. During the follow-up period, there was no complication such as incision ulceration, exudation, bone nonunion, infection recurrence, or infection in the bone harvesting area. Bone healing time ranged from 16 to 37 weeks, with an average of 24.2 weeks. WBC, ESR, CRP, PCT, and elbow flexion, extension, and total range of motions significantly improved at last follow-up (P<0.05). According to Mayo elbow scoring system, the results were excellent in 14 cases, good in 3 cases, and fair in 2 cases, and the excellent and good rate was 89.47%. ConclusionLimited internal fixation combined with a hinged external fixator in the treatment of the peri-elbow bone infection can effectively control infection and restore the function of the elbow joint.
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 evaluate the effectiveness of precise orthormorphia of tibial angulation deformity and shortening deformity by using digital technology combined with external fixator. Methods Twenty-six cases of tibial angulation deformity combined with shortening deformity were treated between June 2012 and August 2016, including 12 males and 14 females aged from 1 to 19 years with an average age of 16.5 years. There were 6 cases of congenital patella pseudoarthrosis, 1 case of fibrous dysplasia of femur and tibia, 3 cases of limb shortening deformity caused by infantile paralysis, 16 cases of fracture malunion. Limb shortening was 1.5-9.5 cm (mean, 6.2 cm) before operation. The deformity from three-dimensional perspective was analysed by digital technology, the surgical procedures of lengthening and osteotomy was simulated, the navigation templates were completed with computer aided design (CAD) and three-dimensional printing, and the external fixator was used to assist the lengthening of the tibia. X-ray films were regularly reviewed after operation to observe the new bone remolding, limb lengthening, load bearing line of lower limb, and recurrences of angulation. Results All the patients were followed up 14-48 months (mean, 18.8 months). There was only 1 case of superficial pin site infection which was cured with oral antibiotics and pin site care with mild disinfectants, and no complication such as bone nonunion, equines deformity, or vascular nerve injury occurred. The deformity of tibia and load bearing line of lower limb had been completely recovered according to postoperative X-ray films at 1 week. All the cases achieved perfect limb length as with preoperative design. The bone mineralization time was 12-20 weeks (mean, 11.6 weeks), the external fixator removal time was 18-26 weeks (mean, 14.9 weeks), and the healing index was 21-78 d/cm (mean, 63.4 d/cm). The postoperative flexion range of the injured limb was 15° less than the unaffected extremity in 1 case, and the situation was improved significantly after some physical manipulation and exercise, who completed the limb lengthening and achieved the expected effectiveness finally. Conclusion Precise orthormorphia of tibial deformity by using digital technology, and limb lengthening with the aid of external fixator can achieve good effectiveness with good reliability, invasiveness, and precision.
ObjectiveTo evaluate the effectiveness of unstable pelvic fractures treated with minimally invasive percutaneous bridge internal fixator or traditional external fixator.MethodsThe clinical data of 45 patients with unstable pelvic fractures who met the selection criteria between January 2013 and February 2018 were retrospectively analyzed. According to the different surgical methods, they were divided into two groups. In the observation group (25 cases), minimally invasive percutaneous bridge internal fixators were used, and three-dimensional printing pelvic models were used to simulate the reduction and fixation before operation to develop individual reduction strategies. In the control group (20 cases), external fixators were used. There was no significant difference between the two groups in gender, age, cause of injury, fracture type (according to Tile classification), and time from injury to operation (P>0.05). The operation time, intraoperative blood loss, fracture healing time, and complications were recorded and compared between the two groups. The reduction quality was evaluated according to the Matta standard, and functional recovery was evaluated according to the Majeed scoring standard.ResultsAll patients were followed up 12-20 months (mean, 15 months). The operation time of the observation group was significantly longer than that of the control group (t=2.719, P=0.009); no significant difference in intraoperative blood loss was found between the two groups (t=0.784, P=0.437). There was no significant difference between the two groups in fracture healing time (t=0.967, P=0.341). According to the Matta standard, the excellent and good rate of the observation group was 92%, and that of the control group was 70%, showing no significant difference between the two groups (χ2=3.748, P=0.053). At last follow-up, according to the Majeed scoring standard, the excellent and good rate of the observation group was 88%, and that of the control group was 60%, showing significant difference between the two groups (χ2=4.717, P=0.030). The incidences of incision and nailway infection, secondary displacement of fracture, and malunion in the observation group were significantly lower than those in the control group (P<0.05); the differences in incidences of iatrogenic injury of lateral femoral cutaneous nerve, deep vein thrombosis, and loosening of fixation between the two groups were not significant (P>0.05).ConclusionMinimally invasive percutaneous bridge internal fixator is a safe and effective method for the treatment of unstable pelvic fractures. It has the advantages of minimal trauma, stable fixation, less interference to patients’ daily life, early functional exercise, and quickly recovery after operation.
ObjectiveTo evaluate the mid-term effectiveness of arthrolysis and hinged external fixation for the treatment of stiff elbow caused by heterotrophic ossification.MethodsBetween January 2014 and December 2017, 11 patients with stiff elbow caused by heterotrophic ossification were admitted. There were 9 males and 2 females with an average age of 32 years (range, 14-48 years), and left side in 6 cases and right side in 5 cases. The cause of stiff elbow included humerus fracture in 5 cases, ulna fracture in 2 cases, fracture of capitulum radii in 1 case, dislocation of capitulum radii in 1 case, terrible triad of the elbow in 1 case, and soft tissue injury in 1 case. The disease duration ranged from 7 to 18 months (mean, 11 months). Preoperative active range of motion of elbow was (19.6±17.5)° and Mayo score was 34.1±9.7. All patients received the treatment of arthrolysis and debridement of heterotrophic ossification lesion combining hinged external fixator, and active and passive rehabilitation with the help of hinged external fixator. The hinged external fixators were removed after 2 months.ResultsAll patients were followed up 13-36 months (mean, 19.1 months). All incisions healed by first intention, and no complication of infection or nerve lesion occurred postoperatively. At last follow-up, the results of X-ray films showed that no heterotrophic ossification recurred. The active range of motion of elbow was (116.4±16.6)° and Mayo score was 93.2±7.8, showing significant differences when compared with preoperative ones (t=17.508, P=0.000; t=16.618, P=0.000).ConclusionThe application of arthrolysis and debridement of heterotrophic ossification lesion combining hinged external fixator can improve the elbow’s range of motion significantly and obtain a good mid-term effectiveness.
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.