Strategies in Trauma and Limb Reconstruction最新文献

Aim: We have encountered four cases with Taylor spatial frames (TSF) (Smith & Nephew, Memphis, TN, USA) with breakage at the half-ring junction of the distal ring. This study examines the strain produced on different locations of the distal ring during loading and the effects on the strain of altering the frame construct.

Materials and methods: We mounted two ring TSF constructs on tibia saw bone models. The proximal ring was the same in all constructs and consisted of a 2/3 180 mm ring attached with three wires. Construct 1 is reproducing the configuration of cases where failure was seen. The distal 155 mm ring is attached with three half pins. The half-ring junction is located in the midline. Construct 2 has a different half pin placement and an additional wire on the distal ring. Constructs 3 and 4 have the same half pin configuration to construct 1 but the distal ring is rotated 60° internally and externally, respectively. Strain gauges were attached to different locations and measurements recorded during loading. Statistical analysis was performed.

Results: Highest strain values were recorded at the half-ring junction of constructs 1 and 2 (>600 microstrains (με) in tension). Rotating the ring 60° internally significantly reduces the strain at the half-ring junction (<300 με) whilst external rotation by 60° further reduces the strain (<180 με). Ring strain is higher in areas close to half pin attachments.

Conclusion: The highest strain is in the half-ring junction as the half rings are subjected to different loading modes. The thickness of the half-ring is halved and the second moment of area reduced further increasing breakage risk. Placing this junction close to the half pin-frame interface, as dictated by the anatomical safe zone further increases the strain. Rotating the distal ring 60° significantly reduces the strain at the half-ring junction.

Clinical significance: Ring breakage is a rare but significant complication. This is the first study to address this potential mode of TSF failure. Insights and technical tips from this study can help reduce this.

How to cite this article: Iliadis AD, Bebja R, Wang K, et al. Reducing the Risk of Ring Breakage in Taylor Spatial Frames: The Effect of Frame Configuration on Strain at the Half-ring Junction. Strategies Trauma Limb Reconstr 2020;15(3):146-150.

Aim: To promote a discussion on the ethics and justifications of stature lengthening in patients without skeletal deformity.

Background: Stature lengthening for height gain in patients without skeletal deformity has stirred controversy within the orthopedic community. However, current literature does not delineate the ethical issues surrounding this procedure. Improvements in the techniques, technology, and safety profile of stature lengthening warrant an ethical discussion to challenge, justify, and guide the use of this surgical procedure.

Review results: Examination of ethical issues leads to the distinction between the dual roles of stature lengthening as a treatment vs an enhancement. The primary focus on stature lengthening as treatment allows for exploration of "height dysphoria"-a psychological burden caused by a dissatisfaction with one's height-as the primary pathology that may justify surgical intervention.

Conclusion: In our opinion, additional work is required to establish "height dysphoria" as a true pathology in order to ethically justify stature lengthening as a legitimate form of treatment. Further discussion is needed to address the ethics of stature lengthening as an enhancement.

Clinical significance: This paper addresses salient ethical issues of stature lengthening in patients without skeletal deformity by exploring historical, contemporary, and comparative contexts.

How to cite this article: Lee RC, Aulisio M, Liu RW. Exploring the Ethics of Stature Lengthening as Treatment for Height Dysphoria. Strategies Trauma Limb Reconstr 2020;15(3):163-168.

Aim: We describe a novel technique of bone splitting and bone grafting in managing hypoplastic or hourglass-shaped regenerated bone in distraction osteogenesis.

Background: Hourglass-shaped regenerated bone is a potential complication during distraction osteogenesis which is vulnerable to fracture when loaded. Our novel technique overcomes this by increasing the diameter of new bone formation via bone splitting and bone grafting.

Case description: We report three cases with hypoplastic regenerated bone following distraction osteogenesis. It was treated with bone splitting and bone grafting. Although one case was complicated with an iatrogenic transverse fracture during the surgery, all three cases achieved the goal of increasing bone diameter during the subsequent consolidation phase.

Conclusion: This relatively simple and novel surgical intervention can overcome the hourglass-shaped appearance, thus preventing potential fracture.

Clinical significance: We emphasise the importance of identifying hypoplastic regenerate bone before the consolidation phase of distraction osteogenesis. The novel technique described is a simple surgical intervention which can prevent potential fracture through the newly formed bone.

How to cite this article: Lee HS, Tasarib R, Hamzah FC, et al. A Novel Technique-Bone Splitting and Bone Grafting in an Hourglass-shaped Bone Following Distraction Osteogenesis. Strategies Trauma Limb Reconstr 2020;15(3):175-178.

Aim: To compare the clinical and radiological outcomes of fixation of olecranon fractures by a transcortical screw with conventional tension band wiring (TBW) using a Kirschner wire (K-wire).

Materials and methods: This is a non-blinded randomised controlled trial comprising two groups (n = 30 each) with Mayo type A olecranon fractures fixed with either TBW or transcortical cancellous screws (CCS). Outcomes included the Mayo elbow performance index (MEPI), time to union, range of motion (ROM), and rates of complication among these two groups.

Results: Most of the patients showed excellent scoring as per MEPI in both the groups at 6 weeks (90% in TBW group and 76.7% in CCS group) and were not significant (p = 0.719). Signs of the radiological union were noted in 80% of the cases at 6 weeks and complete at 6 months. Hardware-related complications (8.3% symptomatic hardware and 6.7% implant back-out), infection, and mean ROM were similar between the two groups (elbow flexion was 142.33 ± 24.67° in TBW group and 143.1 ± 10.19° in transcortical screw group, p = 0.246) at the end of the study.

Conclusion: There were no statistically significant differences in the clinical-radiological outcomes and complications fixing the non-comminuted olecranon fractures with either transcortical screw or TBW.

Clinical significance: Transcortical screw fixation is an acceptable alternative to TBW for non-comminuted olecranon fractures in terms of union and functional outcome.

How to cite this article: Sinha S, Maharjan R, Khanal GP, et al. Comparison of Functional and Radiological Outcomes of Olecranon Fractures Treated with Tension Band Wiring with Kirschner Wires to Transcortical Screw Fixation-A Randomised Controlled Study. Strategies Trauma Limb Reconstr 2020;15(3):131-137.

Aim: To describe the novel hybrid fixation technique for paediatric femoral supracondylar fracture during circular external fixation of the lower limb.

Background: The Ilizarov external fixator is commonly used for various orthopaedic conditions. Difficulties associated with external fixation have previously been described. A fall while using a circular external fixator can cause ipsilateral fracture. Such fractures are ideally treated conservatively, but it is difficult to fix the frame itself. No study has reported the treatment of paediatric femoral supracondylar fracture during circular external fixation. Herein, we describe a novel hybrid fixation technique that was successfully used to treat paediatric femoral supracondylar fracture in three paediatric patients with circular external fixators.

Technique: The fracture was manually manipulated and reduced by slight hyperextension of the lower extremity under general anaesthesia. After confirmation of good reduction, a stockinette, a cast padding, and a thin core cast were applied to the ipsilateral thigh. The hinge parts were attached to the medial and lateral sides of the proximal ring. The rods were connected to the medial and lateral hinges, and the half ring was connected to the ventral side of the proximal end. Under fluoroscopic confirmation, the thin core cast of the thigh and rods were connected by cast rolled in a figure-of-eight manner. The hinges were locked with the knee joint slightly flexed.

Conclusion: The minimally invasive hybrid fixation technique enables conservative treatment of paediatric femoral supracondylar fracture during circular external fixation of the lower limb with no complications, and early exercise and recovery.

Clinical significance: This novel hybrid fixation technique will be an effective method for paediatric femoral supracondylar fracture in patients with a circular external fixator.

How to cite this article: Oka Y, Kim W-C, Yoshida T, et al. Hybrid Fixation for Paediatric Femoral Supracondylar Fracture during Circular External Fixation of the Lower Limb. Strategies Trauma Limb Reconstr 2020;15(3):179-183.

Background: Humeral retroversion (RV) is important to the study of shoulder function and reconstruction. This study tests the hypothesis that clinically obtained computer tomography (CT) measurements for humeral RV (off-axis measurements) differ from those obtained after reformatting the image slice orientation so that the humeral shaft is perpendicular to the gantry (coaxial measurements) and explores deviations from true RV.

Materials and methods: A custom-built application created in Mathematica was used to explore the effect of altering the humeral orientation on slice angle acquisition by 3D imaging technologies, on the perceived angle of RV from the 2D-projection of the reference axes. The application allows for control of humeral axis orientation relative to image slice (3D) or plain of projection (2D) and humeral rotation. The effect of rotating a virtual model of one humerus around its own axis and in discrete anatomical directions on the measured RV angle was assessed.

Results: The coaxial measurement of humeral RV (31.2°) differed from off-axis measurement, with a maximum difference in measured RV of 50° in 45° of extension. The typical position of the humerus in a CT scan resulted in a difference in RV measurement up to 22°. Explorations of deviation led to the following outcomes, as divided by anatomic direction. Extension and abduction led to an underestimation, and flexion and adduction led to an overestimation of the RV-angle.

Conclusion: Measurements must be done consistently about the position and orientation of the humerus. Deviation in the humeral alignment of as little as 10° can distort the measurement of version up to 15°.

How to cite this article: van de Bunt F, Pearl ML, van Noort A. Humeral Retroversion (Complexity of Assigning Reference Axes in 3D and Its Influence on Measurement): A Technical Note. Strategies Trauma Limb Reconstr 2020;15(2):69-73.

Aim and objective: In deformity correction around the knee, the mechanical lateral distal femoral angle (mLDFA) and medial proximal tibial angle (MPTA) are used in surgical planning routinely. While plain radiographs are generally adequate, some surgeons utilise intraoperative arthrograms to visualise the articular contours and assess a younger child's true joint alignment, often with findings that these are discrepant from that measured just using bone alignment. The age cutoff for a discrepancy between the two is not defined.

Materials and methods: We queried our picture archiving and communication systems (PACS) database for MRIs with a radiological read of "normal" for patients between the ages of 4 and 16 years at the time of the study. Anatomic axes were used to determine the anatomic LDFA (aLDFA) and MPTA angles using end-cartilage and end-bone landmarks independently.

Results: We reviewed 116 MRIs, 56% male, with approximately 9 studies per year of age. There were no significant overall differences between aLDFA and MPTA when measured at the bone vs cartilage surfaces (p = 0.42 and p = 0.53, respectively). In the 4- to 6-year age range, there was a significant difference between bony and cartilaginous aLDFA (p = 0.02) but not MPTA (p = 0.88).

Conclusion: In children 6 years of age and younger, intraoperative arthrogram should be considered while treating knee deformity, as plain films may not fully represent the true deformity of the distal femur in particular.

Clinical significance: Supports the need for advanced imaging or intraoperative arthrogram for joint corrective surgery in young patients.

Level of evidence: Level 3 diagnostic.

How to cite this article: Bigach SD, Carender CN, Liu RW. Is Bony Knee Alignment Representative of the True Joint Surface in Skeletally Immature Patients? A Magnetic Resonance Imaging Study. Strategies Trauma Limb Reconstr 2020;15(2):79-83.

Introduction: Limb lengthening using intramedullary nails is an increasingly popular method of achieving limb length equalisation. Currently, the decision regarding when to commence full weight-bearing (FWB) remains largely subjective. Objective criteria for determining the proper timing of FWB would be helpful to limb lengthening surgeons. This study examines using the pixel value ratio (PVR) as an objective method to determine the time to FWB for patients being lengthened with an intramedullary nail.

Materials and methods: A retrospective chart review of 42 patients who underwent unilateral lengthening of the femur was undertaken. The PVR of all four cortices of the regenerate bone was monitored throughout the distraction and consolidation stages to determine the ratio at the time of FWB.

Results: Clinically and radiologically determined FWB was achieved at a mean time of 125.7 ± 30.1 days from surgery. The mean PVR at the time of FWB was 0.94. The medial cortex healed fastest with a mean PVR of 0.96, while the posterior cortex healed slowest with a mean PVR of 0.92.

Conclusion: The PVR is a quick and reliable method to objectively assess the state of healing of the regenerate bone during distraction osteogenesis. We observed that there were no adverse effects when subjects commenced FWB when three out of the four cortices had a PVR of at least 0.93.

How to cite this article: Bafor A, Duncan ME, Iobst CA. Evaluating the Utility of the Pixel Value Ratio in the Determination of Time to Full Weight-bearing in Patients Undergoing Intramedullary Limb Lengthening. Strategies Trauma Limb Reconstr 2020;15(2):74-78.

Aim and objective: Ilizarov hip reconstruction (IHR) is a traditional method of salvaging chronic adolescent problem hips but faces practical problems from external fixators leading to reduced compliance. We present the same reconstruction utilising only internal devices with a modification in technique and aim to review early results.

Materials and methods: We retrospectively evaluated eight patients between 2014 and 2017 with chronic painful hips treated by a two-stage reconstruction; stage 1 included femoral head resection and pelvic support osteotomy using double plating, while stage 2 comprised distal femoral osteotomy avoiding varus followed by insertion of retrograde magnetic nail for postoperative lengthening. Patients continued physiotherapy postoperatively while protecting from early weight-bearing.

Results: At mean follow-up of 19 months (range 6-36), all osteotomies healed with bone healing index of 47 days/cm (range 30-72). Pain improved from 8.3 (range 7-9) to 2 (range 0-6), while limb length discrepancy got corrected from 4.3 cm (range 3-5) to 1.4 cm (range 0-2.5) at final follow-up. Trendelenburg sign was eliminated in three and delayed in five. No examples of infection or permanent knee stiffness were noted. One patient had plates breakage due to mechanical fall and one had 35 mm of lateral mechanical axis deviation requiring corrective osteotomy.

Conclusion: Pelvic support hip reconstruction with exclusive internal devices is a technique in evolution with encouraging early results. It avoids common complications of external fixators and facilitates quick rehabilitation of joints. Refraining from distal varus can effectively eliminate Trendelenburg gait, albeit with some degree of lateral mechanical axis deviation. Unlike external fixation where there is a possibility of gradual correction, this staged procedure of internal fixation is technically demanding with a learning curve.

Clinical significance: Pelvic support hip reconstruction performed by internal implants is a viable alternative to IHR with potential benefits.

How to cite this article: Metikala S, Kurian BT, Madan SS, et al. Pelvic Support Hip Reconstruction with Internal Devices: An Alternative to Ilizarov Hip Reconstruction. Strategies Trauma Limb Reconstr 2020;15(2):91-97.

Limb lengthening by distraction osteogenesis is an accepted orthopaedic surgical technique. The Precice intramedullary lengthening system is the most recent innovation in limb lengthening. Early results have been favourable in femoral lengthening but there is little reported on the outcome in tibial lengthening. The aim of this study is to present our early results of Precice tibial lengthening, and the stepwise evolution of our surgical technique.

Materials and methods: A case series of 17 consecutive tibial lengthenings were prospectively analysed. Healing index, length achieved, range of motion, and complications were recorded. The initial cases followed the recommended surgical technique. Progressive regenerate deformity during lengthening required changes to the surgical method.

Results: No cases were lost to follow-up. All the nails lengthened at the desired rate. There were no complications of infection or poor regenerate formation. Progressive valgus and procurvatum was prevented in later cases by the positioning of Poller blocking screws at the time of nail insertion.

Conclusion: The tibial Precice nail is successful in obtaining length and good regenerate formation. The recommended technique was insufficient to control the deforming forces from the lower limb muscle compartments during lengthening. We therefore recommend the addition of multiple blocking screws in an amended technique.

How to cite this article: Wright SE, Goodier WD, Calder P. Regenerate Deformity with the Precice Tibial Nail. Strategies Trauma Limb Reconstr 2020;15(2):98-105.