Clinical Effect of Suture Anchor and Double-Pulley Technique in the Treatment of Inferior Patellar Fracture.

OBJECTIVE: To evaluate the efficacy of suture anchor combined with double-pulley technique for subpatellar comminuted fractures compared with wire vertical suture and Krachow in the treatment of subpatellar fractures. METHODS: Retrospectively selected 48 patients with subpatellar pole comminuted fracture admitted in our hospital from February 2013 to July 2019, 25 patients with double-pulley technique (group A), and 23 patients with vertical wire suture with Krachow suture. Patient age, gender, AT/OTA typing, injury mechanism, follow-up time, surgical time, bleeding volume, mean fracture healing time, and postoperative complications were recorded. The Insall-Salvati index immediately and 6 weeks after surgery. Bostman scores and knee activity were recorded at each follow-up, and month 12 was taken as the final result. RESULTS: Time of surgery in group A (46.52 min) was significantly shorter than in group B (76.30 min). Intraoperative bleeding in group 15.1 ml, B, group 15.9 ml. Both incisions healed in stage I, averaging clinical healing of patella fracture within 10 weeks. There was no significant difference in mean Bostman score and knee activity at month 12 (group A: 28.4, 124.8°; group B: 28.1, 125.7°). There was no significant statistical difference in the Insall-Salvati index immediately or 6 weeks between the two groups. Group B patients had two wire fractures, fracture healing and the wire removed one year after surgery, and the remaining patients had no complications such as internal fixation loosening, fracture, delayed healing, or nonhealing of fracture. CONCLUSION: Compared with the treatment of subpatellar fracture with wire vertical suture and Krachow method, suture anchor with double-pulley technique has short operation time, reliable fixation, and less complications. Patients can have early functional exercise and good knee function recovery without secondary surgery. It can be considered as an alternative therapy for this fracture and deserves clinical adoption and promotion.

A biomechanical matched-pair comparison of two different locking plates for tibial diaphyseal comminuted fracture: carbon fiber-reinforced poly-ether-ether-ketone (CF-PEEK) versus titanium plates.

BACKGROUND: Several methods have been proposed to reduce plate construct stiffness and promote secondary bone healing. In this study, we explored the stiffness and strength of the new carbon fiber-reinforced poly-ether-ether-ketone (CF 50) plate compared with the titanium alloy plate (Ti6Al4V). METHODS: Titanium and CF-PEEK locking plates were tested in a tibial non-osteoporotic diaphyseal comminuted fracture model to determine construct stiffness in axial compression, torsion, and bending. Subsequently, constructs were loaded until construct failure to determine construct strength. RESULTS: Relative to the titanium locking plate, the stiffness of the CF-PEEK locking plate was 6.8% and 30.8% lower in 200 N and 700 N axial compression, respectively (P < 0.05), 64.9% lower in torsion (P < 0.05), and 48.9% lower in bending (P < 0.05). The strength of the CF-PEEK locking plate was only 2.6% lower under axial compression, 7.8% lower in torsion, and 4.8% lower in bending than the titanium locking plate (P > 0.05). CONCLUSIONS: The CF-PEEK locking plate significantly reduced axial, torsion, and bending stiffness compared with the titanium locking plate. Nonetheless, axial, torsional, and bending strength showed only a modest reduction. Considering its other advantages, which include radiolucency and artifact-free imaging, the CF-PEEK locking plate therefore deserves further clinical investigation.

Does a staged treatment of high energy tibial plateau fractures affect functional results and bony union? A case series.

PURPOSE: Tibial plateau fracture (TPF) is a devastating injury as it shatters lower articular surface of the largest joint. Apart from bony injury, TPF can lead to great soft tissue envelope compromise which affects the treatment plan and outcome. In the present study, clinical results were assessed in cases of high energy TPFs treated in staged manner. METHODS: Twenty-three (20 males and 3 females) patients of high energy communited TPFs (Schatzker type V and VI) were consecutively treated.1 All the patient had compromise of overlying skin conditions. They were all successively scheduled for staged treatment plan which comprised of application of bridging knee external fixator on the first day of admission and definitive internal fixation after skin and soft tissue overlying the fracture were healed. Schatzker type I, II, III and IV were excluded from the study. Primary survey was done and patient who had head injury, chest and abdominal injury, pelvic injury and contralateral limb injury and open fractures were excluded from the study. The patients were also evaluated in terms of wound complications, axial and rotary alignment of limb, fixation failure, articular congruity and range of motion of the knees and post injury employment. Statistical analysis was done using SPSS software. RESULTS: Maximum follow-up period was 13 months. All the fractures were united at final follow-up. Clinical evaluation was done with the Tegner Lysholm knee scoring scale.2 Excellent results were found in 78% cases and good and fair results in 22% cases. There was significant correlation between range of motion and the Tegner Lysholm knee score (p < 0.001, Pearson correlation coefficient = 0.741). The correlation between the score and the radiographical union duration was significant (p = 0.006, Pearson correlation coefficient = -0.554). CONCLUSION: A staged treatment plan allows healing of soft tissue envelope, with avoidance of dreadful complications such as compartment syndrome and chronic infection. In addition, a staged treatment strategy does not hamper the fracture reduction, bony union and the functional results.

Posttraumatic Malunion Following Comminuted Scapular Fracture.

A 42-year-old male police officer sustained multiple injuries in a motorcycle accident, including a comminuted fracture of the scapula and several rib fractures. Four months after his injury, the patient was prescribed outpatient physical therapy, after 2 months of which the patient's cervical and lumbar spine function were restored but his shoulder mobility deficits persisted. A second physical therapy opinion was sought 6 months post injury for the left shoulder. Given his functional deficits, including an inability to return to work, he was referred to an orthopaedist for additional imaging and consultation, which revealed scapular malunion. J Orthop Sports Phys Ther 2020;50(3):167. doi:10.2519/jospt.2020.8927.

The Comparison of Postoperative Outcomes Open and Closed Reduction for Patellar Fractures.

Patellar fractures account for approximately 1% of all human body fractures. This study aimed to compare the surgical outcomes of open reduction and closed reduction for patellar fractures. This retrospective study included 62 patients (63 cases) who underwent surgical treatment of patellar fractures from 2008 to 2013. Of the 63 cases, open and closed reductions were performed in 42 and 21 cases, respectively. Plain radiography was used to assess fracture healing. Comminuted patellar fracture was the most common fracture type in both groups. Tension band wiring and cannulated screw fixation were mainly used in the open and closed reduction groups, respectively. There was no significant difference in the modified hospital for special surgery score, visual analog scale score for pain, and range of motion between the two groups. The mean union time was 3.2 and 3.0 months in open and closed reductions, respectively. Postoperative knee stiffness was noted in five cases of open reduction and in three cases of closed reduction. One patient in the open reduction group had a refracture. There were no notable differences in treatment outcomes between open and closed reductions. Thus, closed reduction may not be inferior to open reduction as a surgical treatment for patellar fractures.

Finite element analysis of an intramedulary anatomical strut for proximal humeral fractures with disrupted medial column instability: A cohort study.

BACKGROUND: Lateral locking plate (LLP) fixation has gained popularity for the treatment of proximal humeral fractures (PHFs); however, complications can occur due to loss of the medial cortical buttress from fracture comminution. MATERIALS AND METHODS: We designed a novel intramedullary anatomical medial strut with allograft bone (IAMSAB) using MIMICS software to specifically fill the intramedullary canal of the proximal humeral bone. We used finite element analysis to evaluate the biomechanical characteristics of a LLP, LLP-intramedullary fixation system (IFS), LLP-anatomical medial locking plate (AMLP), or the combined application of a LLP and IAMSAB (LLP-IAMSAB) fixation construct in patients with a PHF and an unstable medial column. RESULTS: For axial or rotational loads, under (normal) Nor or osteoporotic (Ost) bone conditions, the LLP-IAMSAB fixation construct was significantly stiffer than the LLP-IFS fixation construct, and displacement at the fracture site after LLP-IAMSAB fixation was significantly less than after LLP or LLP-IFS fixation (P < 0.05). Stiffness of the LLP-IAMSAB and LLP-AMLP fixation constructs and displacement at the fracture site after LLP-IAMSAB and LLP-AMLP fixation were not significantly different. The IFS, AMLP, and IAMSAB shared the load in the LLP and decreased the risk of implant failure. There were no significant differences in von Mises stress and stress distribution after fixation with the LLP-IFS, LLP-AMLP, and LLP-IAMSAB constructs. CONCLUSION: These data suggest that the IAMSAB can provide direct medial support or resistance to rotation and augment the biomechanics of the LLP. The combined application of the IAMSAB and LLP may achieve functional outcomes that are similar to the LLP-AMLP fixation construct.

Low Bone Mineral Density of the Forearm and Femur among Postmenopausal Women with Metaphyseal Comminuted Fracture of the Distal Radius.

Osteoporosis is characterized by bone loss and skeletal fragility and is likely to occur in postmenopausal women. Distal radius fracture is a type of fragility fractures associated with osteoporosis. Bone mineral density (BMD) refers to the amount of mineral in bone tissue and is an indicator of osteoporosis. This study aimed to investigate the relationship between the severity of distal radius comminution and the BMD of the healthy contralateral forearm and femur in postmenopausal women. Of 165 women who sustained low-energy trauma from falls on flat ground, forearm and femoral neck BMDs were measured in 155 and 163 participants, respectively. Evaluation of distal radius comminution was performed by computed tomography, and the severity is classified based on the degree of articular surface comminution and on the presence of metaphyseal comminution. We thus evaluated 165 cases of articular surface comminution (extra-articular, 43 cases; intra-articular simple, 91 cases; and intra-articular multifragment, 31 cases) and metaphysis comminution (metaphyseal simple, 58 cases; metaphyseal monocortical comminution on either the palmar or dorsal side, 82 cases; and metaphyseal bicortical comminution on the palmar and dorsal sides, 25 cases). There was no significant association between intra-articular comminution and BMD of the forearm and femur. By contrast, the participants with metaphyseal bicortical comminution showed lower BMD of the forearm and femur compared with other types of metaphysis comminution (p < 0.05). In conclusion, postmenopausal women who developed bicortical comminuted fractures of the distal radius tend to have lower femoral BMD, which may predispose them to future hip fractures.

Preserving the radial head in comminuted Mason type III fractures without fixation to the radial shaft: a mid-term clinical and radiographic follow-up study.

BACKGROUND: The treatment of multifragment Mason type III fractures is challenging. Open reduction-internal fixation (ORIF), radial head arthroplasty, and in some cases, even radial head resection are the current options; however, each of these treatment methods is associated with characteristic benefits and complications. We present our experience with a radial head salvage procedure in comminuted radial head fractures irrespective of concomitant injuries, which are not accompanied by typical ORIF-related complications. METHODS: The first group comprised 29 patients with multifragment Mason type III fractures treated surgically with biological radial head spacers (group S). The fragments were reduced and fixated in an extracorporeal manner, and the reconstructed radial head was placed in its anatomic position without fixation to the shaft. The second group comprised 12 patients treated with conventional ORIF using mini-fragment plates (group P). RESULTS: Thirty patients were enrolled to undergo clinical and radiographic follow-up at an average of 76 months (range, 12-152 months). In group S, nonunion at the head-neck junction developed in 70% of the cases; however, the overall Mayo Elbow Performance Index averaged 94.8, which was superior to the average Mayo Elbow Performance Index of 83.1 in group P. Radiographic evaluation showed development of osteoarthritic changes in 75% of patients in group S and 62.5% in group P. None of the patients had wrist-joint pain. CONCLUSIONS: Preserving the native radial head in comminuted Mason type III fractures without fixation to the radial shaft is a reliable option. Excellent functional results can be expected; however, the development of osteoarthritis cannot be impeded.

Biomechanical Comparison of Fixed- versus Variable-Angle Locking Screws for Distal Humerus Comminuted Fractures.

BACKGROUND: To compare the stability of fixed- versus variable-angle locking constructs for the comminuted distal humerus fracture (AO/OTA 13-A3). METHODS: Eight pairs of complete humeri harvested from eight fresh frozen cadavers were used for the study. We fixed the intact humeri using 2.7-mm/3.5-mm locking VA-LCP stainless steel distal humerus posterolateral (nine-hole) and medial (seven-hole) plates. An oscillating saw was used to cut a 1-cm gap above the olecranon fossa. The specimens were loaded in axial mode with the rate of 1 mm per 10 seconds to failure, and stress-strain curves were compared in each pair. The mode of failure was recorded as well as the load needed for 2- and 4-mm displacement at the lateral end of the gap. RESULTS: The stiffness of the constructs, based on the slope of the stress-strain curve, did not show any difference between the fixed- versus variable-angle constructs. Likewise, there was no difference between the force needed for 2- or 4-mm displacement at the lateral gap between the fixed- and variable-angle constructs. The mode of failure was bending of both plates in all specimens and screw pull-out in four specimen pairs in addition to the plate bending. CONCLUSIONS: Our results did not show any difference in the biomechanical stability of the fixed- versus variable-angle constructs. There was not any screw breakage or failure of the plate-screw interface.

How effective is skyline view for avoiding dorsal cortex penetration in volar plate fixation of intra-articular and dorsal cortex comminuted distal radius fractures.

OBJECTIVES: The incidence of osteosynthesis is increased by volar anatomic plate used for treatment of distal radius fractures and this increases the incidence of wrist extensor tendon irritation, a postoperative complication of the aforementioned surgical technique. The purpose of this study; was to evaluate the intraoperative skyline view which is commonly used to prevent dorsal cortex penetration of distal screws during the surgical treatment of intra-articular distal radius fractures with comminuted dorsal cortex with CT (computed tomography) scanning to determine its effectiveness. In the literature review, no other study focused on similar fracture types was found. METHODS: 52 patients with a minimum follow-up of 13 months were included in the study. These patients were operated by two different national board certified surgeons. One of the surgeons unlike the other, adopted intraoperative skyline view method. X-ray and CT scans which were performed preoperative and postoperative first day, were evaluated by a senior author with a blind evaluation method. Fractures were classified according to AO/OTA (Orthopaedic Trauma Association) classification and postoperative dorsal cortex penetrations were registered. RESULTS: Intra-articular distal radius fractures with comminuted dorsal cortex (AO/OTA 2R3C2, C3) were detected in 25 of the patients and no significant difference between two groups for the distribution of these patients was found. The CT scan of 14 patients showed dorsal cortex screw penetration and this rate was significantly higher in the group, in which intraoperative skyline view was not used (p > 0,05). In the postoperative CT examination, the most common dorsal cortex penetration was related to the 4th distal screw (42.9%) which were inserted the nearest ulnar hole of plate. CONCLUSION: The insertion of a distal screw 2 mm (millimeter) shorter than the length measured with the help of skyline view is considered to be a more effective method than other intraoperative methods for preventing dorsal cortex penetration. In addition, more comprehensive studies are required in order to recommend the mono-cortex fixation, in which distal screws measuring 4 mm shorter are used.

Hook plating in patella fractures.

PURPOSE: Tension band wiring is considered the standard treatment for patella fractures. However, it is limited for fractures with marginal involvement, comminution, and osteoporotic bone. Our experience indicates that these limitations can be overcome with the hook plate. We evaluated the radiographic and clinical outcomes in patients with patella fracture treated with hook plating. METHODS: We enrolled 30 patients who underwent hook plating for patella fracture at two institutions between 2013 and 2017. Fracture classification and surgical options were reviewed. Postoperative fracture gap and time to union as radiographic measurements, and complications, range of motion, and functional outcome with the Lysholm score as clinical outcomes, were evaluated retrospectively. RESULTS: Nine fractures were AO/OTA 34A1, three B1, one B2, two C1, nine C2, and six C3. All were closed fractures. There were 3 cases of revision, 4 with lateral or medial marginal fracture, 9 with isolated inferior pole fracture, and 14 with comminuted fracture. The average postoperative fracture gap was 0.4 (range, 0-2.0) mm, and bone union was achieved without additional intervention. The average time to union was 11.6 (range, 7-24) weeks. There were no complications, and no extension lag except in one case (10°). The average flexion was 138.5° (range, 110-145°). For functional outcomes, the average Lysholm score was 89.5 (range, 74-95), with 13 excellent, 14 good, 3 fair, and no poor cases. CONCLUSION: This study suggests that hook plating can result in good bone union and restored knee function in marginal or comminuted fractures of the patella.

Non-union in lateral locked plating for distal femoral fractures: A systematic review.

INTRODUCTION: This study aims to identify patient and intra-operative factors that contribute to non-union in locked lateral plating for distal femoral fractures. METHODS: Systematic searches of English-language articles in Ovid Medline, PubMed, Embase, Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews were undertaken in February 2018 according to the PRISMA guidelines. The search terms were (fracture or fracture*) AND (distal femur or distal femoral) AND (malunion or non-union). Eligible studies published at any time reported non-union rates and compared patient and intraoperative factors in patients who underwent locked lateral plating for traumatic distal femoral fractures. The quality of included papers was assessed using The Journal of Bone and Joint Surgery levels of evidence (Wright et al., 2003), and further appraised using the Downs and Black score (Downs and Black, 1998). RESULTS: Eight studies investigating 1380 distal femoral fractures were found to satisfy the inclusion and exclusion criteria. These studies analysed a variety of patient and intra-operative factors that may contribute to non-union. These include high BMI, open fracture, comminution, fracture infection, stainless steel plate material, shorter working length, open reduction and internal fixation when compared with minimally invasive plate osteosynthesis, high construct rigidity scores and purely locking screw constructs. CONCLUSION: This review has identified multiple factors which potentially contribute to non-union including stainless steel plate material, high construct rigidity scores and purely locking screw constructs. These findings may reflect that overly rigid plating constructs can contribute to non-union. However, they should be taken in the context of heterogeneity amongst included studies, with further research necessary to support these findings.

Dual Nonlocked Plating as an Alternative to Locked Plating for Comminuted Distal Fibula Fractures: A Biomechanical Comparison Study.

The purpose of this cadaveric study was to compare the biomechanical properties of dual nonlocked plating and single-locked plating using matched pairs of isolated fibula specimens. Fractures were simulated in 10 matched pairs of isolated cadaveric fibulae and plated with a single lateral locking plate for right-sided specimens, or with a one-third tubular plate and a 7-hole 2.4-mm minifragment adaption plate for left-sided specimens. An external rotation torque was applied at a rate of 1°/second, and torque at 10° was measured. Each fibula specimen was evaluated using a micro computed tomography scanner, and bone mineral density was calculated as milligrams of bone per cubic centimeter of volume. Dual nonlocked plating and locked plating specimens demonstrated torque measurements that were not significantly different at 10° of external rotation (1.48 N·m and 1.92 N·m, respectively; p = .093). The stiffness of the dual nonlocked plated and locked plating constructs were not significantly different (p = .228 and p = .543, respectively). The effect of bone mineral density on maximum torque at failure was not a reliable predictor of maximum torque in either the dual nonlocked plating or locked plating specimens (R2 = 0.548 and R2 = 0.096, respectively). We found no differences in torque at 10° of external rotation or stiffness between locking plate and dual nonlocking plate fixation constructs. This study provides evidence that dual nonlocked plating likely constitutes adequate fixation in situations in which a locking plate is being considered for comminuted distal fibula fractures.

Repair of Bado II Monteggia Fracture: Case Presentation and Surgical Technique.

INTRODUCTION: Monteggia fractures are rare, although complex elbow injuries. Bado II Monteggia fractures are characterized by posterior dislocation of the radial head and concurrent fracture of the proximal or middle third of the ulna. This video demonstrates the open reduction and internal fixation of a complex Bado II Monteggia fracture dislocation. METHODS: The patient is a 65-year-old woman with a Bado II Monteggia fracture after a low-energy fall from standing height. Given the extent of comminution and the instability of the elbow, the patient was indicated for surgical fixation. RESULTS: This video demonstrates a locking plate technique for repair of a comminuted fracture of the proximal ulna. Anatomical reduction of ulnohumeral and radiocapitellar joints and stable fixation with bone grafting of the fracture are achieved with a medial 2.0/2.4-mm plate and a dorsal precontoured variable-angle locking plate. Demonstration of radial head arthroplasty is provided as an alternative for utilization in cases with a radial head fracture. CONCLUSIONS: Anatomical reduction and fixation of complex Monteggia fracture dislocations can be achieved with adherence to standard aspects of bony reconstruction. In this video we present the case of a Bado II Monteggia fracture surgically repaired with a locking plate construct.

Nonoperative Comminuted Hamate Fracture.

A US Navy sailor was seen at an emergency department after falling on her outstretched hand. A computed tomography (CT) scan demonstrated a comminuted, nondisplaced dorsal hamate fracture. After 8 weeks of cast immobilization, a CT scan revealed no healing and physical therapy was initiated. Following 4 weeks of physical therapy, a third CT scan was performed and demonstrated partial fracture healing without displacement, so physical therapy continued. J Orthop Sports Phys Ther 2019;49(7):557. doi:10.2519/jospt.2019.8514.

Treatment of open intraarticular distal femur fractures by Ilizarov fixator; an approach to improve the outcome with mid-term results.

PURPOSE: Open comminuted intraarticular distal femur fracture represents a formidable challenge for the orthopaedic surgeon for the inherent fracture complexity, soft tissue damage, and contamination. The purpose of this study was to evaluate the mid-term outcome results and safety of using the Ilizarov fixator to treat these fractures. PATIENTS AND METHODS: The study included 22 fractures treated by debridement with reduction and stabilization by Ilizarov external fixator. The mean age was 35 years. Gustilo grade of open fracture was III-A (19 cases), III-B (2 cases), and III-C (1 case). Six fractures were AO-OTA type 33C2, and 16 cases were type 33C3. Eight patients had associated injuries. Bone and functional results were evaluated by Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria, and Neer knee score. The statistical analysis was done using the IBM SPSS Statistics for Windows. RESULTS: Seven cases had autogenous bone grafting. The frame crossed the knee in 8 patients. The fixator was removed after a mean of 7 months with union in all cases, and without any malalignment >5°. Deep infection occurred in two cases. Quadriceps-plasty was needed for 3 cases. After a mean of 44 months, the last follow-up results showed full knee extension and a mean flexion of 107.59°. The ASAMI functional and bone results were good to excellent in all cases. Neer knee score averaged 86.59. CONCLUSIONS: Ilizarov fixator was an effective treatment modality of open comminuted distal femur fractures with high union rate, adequate alignment and satisfactory functional outcomes.

The use of dorsal distraction plating for severely comminuted distal radius fractures: A review and comparison to volar plate fixation.

INTRODUCTION: Optimal fixation for highly comminuted distal radius fractures remains a major treatment challenge for orthopaedic surgeons. Dorsal distraction plating can serve as an improved fixation technique by allowing reduction under ligamentotaxis, providing a dorsal buttress, addressing proximal comminution, and allowing for early weightbearing in polytrauma patients. The aim of this study was to review current literature regarding treatment of distal radius fractures treated with dorsal distraction plating. METHODS: We performed a literature search in Pubmed and EMBASE databases to identify all studies analyzing use of dorsal distraction plating. Case reports, biomechanical and anatomic cadaver studies were excluded from analysis. Primary outcome measures were range of motion (ROM) at final follow up, grip strength, and radiographic parameters. RESULTS: Eight studies were included in the final analysis. Pooled mean ROM after dorsal distraction plating was found to be 47.6° of flexion, 50.5° of extension, 76.0° of pronation, and 74.2° of supination. Pooled mean grip strength was 79.1% compared to the uninjured contralateral limb. Pooled mean volar tilt was 3.6°. Overall radial height was maintained at an average of 10.5 mm with a pooled mean loss of only 3.8 mm in length. Mean radial inclination was found to be 19.4 mm with patients having a mean ulnar variance of 0.5 mm. DISCUSSION & CONCLUSION: Treatment of comminuted intra-articular distal radius fractures with dorsal distraction plating yielded excellent outcomes with very low complication rates, and has several advantages over volar plating and/or external fixation for these fractures. Necessity of plate removal remains a negative feature of this technique.

A biomechanical investigation of thoracolumbar burst fracture under vertical impact loads using finite element method.

BACKGROUND: A sudden vertical impact load on spine can cause spinal burst fracture, especially in the thoracolumbar junction region. This study aimed at investigating the mechanism of spinal burst fracture under different energy vertical impact loads, producing the failure risk region to understand burst fracture, reducing nervous system damage and guiding clinical treatment. METHODS: A nonlinear finite element model of T12-L1 motion segment was created to analyze the response of the vertical impact load. A rigid ball was used to impact the segment vertically to simulate the vertical impact load in practice. There were three different mass balls to represent the different loads: low energy, intermediate energy and high energy (respectively 13 J, 30 J and 56 J). The results of impact force, vertical displacement, stress, intradiscal pressure and contact force were obtained during the process. FINDINGS: At low energy condition, the rigid ball rebounded rapidly. At intermediate energy condition, fractures were initiated in vertebral foramen and left rear regions on the superior cortical bone near the superior endplate of L1. At high energy condition, burst fracture occurred and a part of L1 was isolated from the model. INTERPRETATION: The fracture occurred on the L1 segment only at the intermediate energy and high energy. The strength of vertebral body under low and intermediate energy was enough to support the impact. The burst fracture pattern at high energy was also observed in clinical practice. The findings may explain the mechanism of burst fracture.

Use of external fixation for juxta-articular fractures in children.

In this article, the use of external fixation in the management of juxta-articular fractures in paediatric patients is discussed. Basic principles of Ilizarov technique are described for distal radial, distal femoral, distal humeral and distal tibial fractures. Common indications for external fixation in pediatric fractures are comminuted, complicated, and/or open fractures, particularly at the distal humerus, distal radius, distal femur and distal tibia. There are several benefits of external frame fixation in these type of injuries in children. This method avoids additional injury to the growth plate as K-wires are not placed through it. It enables careful reduction without interfragmentary compression and correct anatomic alignment. There is no soft tissue dissection and periosteal blood supply is preserved. External fixation ensures primary fracture stability even in presence of comminution and high adjustment capability. Immediate joint motion and early weight-bearing are further advantages. Joint bridging is an option in severe bone loss or soft tissue injuries.

[An Experience of Using a Distraction Plate for an Elderly Patient with a Highly Communited Intraarticular Distal Radius Fracture].

We performed open reduction and internal fixation using a distraction plate in two cases of elderly patients with highly communited intraarticular open distal radius fractures. There was no corrective loss of intraarticular fracture fragment in either case. The implant was removed in one case because bone union was achieved. The plate was retained in the other case, without the hope of implant removal. Neither case complained of any marked disturbance of activities of daily living (ADL), and there was no pain at the time of the final follow up period. However, there is a high possibility of limitation of the range of motion (ROM) of the wrist after implant removal, therefore we need to judge the indications carefully.