Comparison of two types of fixation for proximal tibial epiphysiodesis: An experimental study in a rabbit model.

OBJECTIVES: In this study, we describe a novel hemiepiphysiodesis technique to prevent implant-related perichondrial ring injury in a rabbit model. MATERIALS AND METHODS: Proximal tibial epiphyseal plates of a total of 16 white New Zealand rabbits were used for this animal model. The subjects were divided into three equal groups as follows: Group 1 (Kirschner wire [K-wire]/cerclage), Group 2 (8-plate) right-hind legs, Group 3 (Control) left hind legs. Using anteroposterior radiography, the medial slope angle (MSA), articular line-diaphyseal angle (ALDA), and the angle between screws of 8-plate in lateral X-ray tibial slope angle (TSA) were measured. The radiographs were taken early postoperative (Day 1) and on sacrification day (Week 8). The histological evaluation of the perichondrial ring was made on a 7-mm axial section that stained with Safranin O/fast green at X10 magnification. RESULTS: In both K-wire and 8-plate groups, the early postoperative ALDA and TSA were greater than the sacrification ALDA and TSA (p=0.028 and p<0.001, respectively). The early postoperative MSA was lower than the sacrification MSA in groups, (p<0.001). The MSA in the control group was lower than the K-wire and 8-plate groups (p<0.001 and p=0.009; respectively). The perichondrial ring thickness of the K-wire group was greater than the 8-plate group in histological evaluation (p<0.001). CONCLUSION: Both of the K-wire and 8-plate groups showed similar angulation effects in the proximal tibia, although histologically less damage to the perichondrial ring was observed in the K-wire group, compared to the 8-plate group.

The Community Orthopaedic Surgeon Taking Trauma Call: Radial Neck Fracture Pearls and Pitfalls.

Pediatric radial neck fractures will inevitably be encountered by the general orthopaedist, and they carry great potential for poor outcomes. Acceptable displacement varies by age, and unlike adults, most of these injuries can be managed by closed means. If they are taken to the operating room, the mainstays of treatment are percutaneous techniques. Increasing patient age, inadequate reduction, unnecessary open reductions, and prolonged immobilization are all associated with worse outcomes, most commonly manifesting as significant elbow stiffness. Knowledge of the age-specific acceptable displacement criteria, a stepwise approach to closed and percutaneous techniques, and safe strategies for open reduction when needed as a last resort will greatly improve treatment success.

Percutaneous Kirschner Wire Versus Commercial Implant for Hammertoe Repair: A Cost-Effectiveness Analysis.

Hammertoe deformities are one of the most common foot deformities, affecting up to one third of the general population. Fusion of the joint can be achieved with various devices, with the current focus on percutaneous Kirschner (K)-wire fixation or commercial intramedullary implant devices. The purpose of the present study was to determine whether surgical intervention with percutaneous K-wire fixation versus commercial intramedullary implant is more cost effective for proximal interphalangeal joint arthrodesis in hammertoe surgery. A formal cost-effectiveness analysis using a decision analytic tree model was conducted to investigate the healthcare costs and outcomes associated with either K-wire or commercial intramedullary implant fixation. The outcomes assessed included long-term costs, quality-adjusted life-years (QALYs), and incremental cost per QALY gained. Costs were evaluated from the healthcare system perspective and are expressed in U.S. dollars at a 2017 price base. Our results found that commercial implants were minimally more effective than K-wires but carried significantly higher costs. The total cost for treatment with percutaneous K-wire fixation was $5041 with an effectiveness of 0.82 QALY compared with a commercial implant cost of $6059 with an effectiveness of 0.83 QALY. The incremental cost-effectiveness ratio of commercial implants was $146,667. With an incremental cost-effectiveness ratio of >$50,000, commercial implants failed to justify their proposed benefits to outweigh their cost compared to percutaneous K-wire fixation. In conclusion, percutaneous K-wire fixation would be preferred for arthrodesis of the proximal interphalangeal joint for hammertoes from a healthcare system perspective.

A New Device for Securing Sternal Wires After Median Sternotomy: Biomechanical Study and Retrospective Clinical Assessment.

OBJECTIVE: Morbidity due to sternotomy continues to be a significant clinical problem. Poor approximation of the sternum may lead to complications such as sternal dehiscence, infection, and pain. A device to assist in tensioning and twisting standard steel wires during sternal closure has been developed (TORQ sternal closure device). Manually tightened interrupted wire closures were compared with those tightened and secured with the aid of the device. Performance of the device was assessed clinically. METHODS: Four cardiovascular surgeons performed manual and device-assisted closures on a biofidelic model. Closure force was measured to determine the residual force and its intraoperator variation. A retrospective review of patients treated before and after the introduction of the device was conducted. Predicted and actual outcomes were compared for the two groups (manual closure and device-assisted closure). RESULTS: Biomechanical testing measured a 75% increase in residual closure force (P < 0.001) and a significant reduction in the variability of the closure force (P = 0.045) for device-assisted closures compared with manual closures. In the retrospective study, 3 of 173 manually closed patients had sterile sternal dehiscence and 1 of 173 had a deep sternal wound infection. In the device closure group, 2 of 127 had a sterile sternal dehiscence and no deep sternal wound infections were reported. No other device-related serious adverse events were reported. CONCLUSIONS: Biomechanical data showed stronger, more consistent closure forces with the device. The retrospective data attest to the performance of the device.

Treatment of proximal humerus fractures in children with a modified palm tree technique.

Although most pediatric proximal humeral fractures can be successfully treated conservatively with satisfactory results, many operative techniques have been described for the treatment of displaced proximal humeral fractures. The aim of this study is to evaluate the efficacy of percutaneous fixation using a modified palm tree technique for proximal humerus fractures in children. Between March 2011 and May 2013, the modified palm tree technique was used for the management of 30 children (20 boys and 10 girls) with displaced proximal humeral fractures. The average age of the patients was 11.5 years (age range from 8 to 15 years). They were evaluated clinically by the Constant-Murley score and by radiological analysis. The average follow-up duration was 18 months. The average time of fracture union was 6 weeks (range from 4 to 8 weeks). The average Constant score of the patients was 92 (range from 87 to 95), with excellent results in 27 (90%) cases, good results in three (10%) cases, and no fair or poor results (0%). The reported complications were superficial pin-tract infection in five cases, treated by daily dressing and local antibiotics, and malunion with a varus deformity in two cases (about 15°), with no recorded cases with deep infection. None of the cases required open reduction. No cases were complicated by avascular necrosis of the head humerus or loss of fixation. Kirschner wires were removed after an average period of 7 weeks. The modified palm tree technique represents an efficient method for the treatment of proximal humerus fractures in children. It produces a good grip in both the proximal and distal fragments. It allows for early joint movements.

Mandibular body fracture repair with wire-reinforced interdental composite splint in small dogs.

OBJECTIVE: To report the outcome of mandibular body fractures treated with a wire-reinforced interdental composite splint (WRICS) in small breed dogs. STUDY DESIGN: Retrospective case series. ANIMALS: Client-owned small breed dogs (n = 24). METHODS: Medical records (1998-2012) of small breed dogs (<10 kg) with mandibular body fractures treated by WRICS were reviewed for signalment, history, type of fracture, treatment, and clinical and radiological follow-up. The angle of the fracture line (ANG) was measured on dental radiographs. A mandibular injury severity score (MISS) and a dental injury score (DIS) were evaluated as potential prognostic factors. RESULTS: Fractures most commonly involved P4-M1 (56%), and healed in a mean time of 2.37 ± 0.7 months. Healing was slower (P = .012) if teeth were present in the fracture line and required extraction, hemisection, or root canal therapy prior to WRICS placement (2.39 ± 0.7 months) than if no dental treatment was required (1.46 ± 0.8 months). Contrary to the MISS, the DIS was associated with longer time to bone healing (P = .001; r = .63) and risk of complications (P = .004). Bone healing time was decreased (P = .003; r = .61) with increasing fracture angles. CONCLUSION: WRICS can be considered to treat mandibular body fractures in small breed dogs if the fracture is not severely comminuted, and if at least the canine and first molar tooth can be used for anchorage. More severe lesions, such as those with teeth in the fracture line and a shorter fracture surface, are associated with prolonged bone healing.

Subtrochanteric fractures in elderly people treated with intramedullary fixation: quality of life and complications following open reduction and cerclage wiring versus closed reduction.

INTRODUCTION: Subtrochanteric fractures are more difficult to treat than other proximal femoral fractures. The aim of this study was to report the outcomes for patients with subtrochanteric fractures treated using a cephalomedullary nail following open reduction and cerclage wiring versus closed reduction alone, regarding health-related quality of life (HRQoL) and social function. MATERIALS AND METHODS: We performed a prospective cohort study including patients aged 60 years or older suffering fragility subtrochanteric fractures of the femur treated with cephalomedullary nails, with a minimum 2-year follow-up. We defined two treatment groups: one treated with closed reduction manoeuvres (60 patients), and another treated with open reduction and cerclage wiring (30 patients). The outcomes were mortality, orthopaedic complications (reoperation and no-union), social function (Jensen Index), and HRQoL (EQ-5D index score). RESULTS: There were no differences regarding sex, age, side affected, type of implant, anaesthetic risk, 1-year mortality, and orthopaedic complications. Surgical time was longer in the cerclage wire group, but length of stay was 2 days shorter for the cerclage group and reduction was better. Patients treated with cerclage wiring had significantly better EQ-ED at 12 months (0.66 ± 0.22 points vs. 0.78 ± 0.15 points); and social status at 12 and 18 months (2.77 ± 1.00 points vs. 2.10 ± 1.22 points). CONCLUSIONS: Better reduction is achieved when using cerclage wires for fragility subtrochanteric fractures. These fractures had a negative effect on quality of life and social function, but better outcomes were observed in the cerclage group.

Antibiotic Use and Kirschner Wire Fixation in Forefoot Surgery: A National Survey.

In foot and ankle patients, the use of Kirschner wires is common, and the population in the typical foot and ankle practice has higher rates of comorbidities associated with infection. This study assessed national trends regarding the use of postoperative prophylactic antibiotic therapy in patients undergoing foot and ankle surgery treated with percutaneous Kirschner wires. Attending physicians at foot and ankle fellowships were mailed a questionnaire that included 3 clinical vignettes containing questions on the use of postoperative antibiotics in patients treated with percutaneous Kirschner wires. A total of 112 physicians were identified; 64 physicians (57%) returned the survey. In the first case of a nondiabetic patient, 16 physicians (25%) indicated they would place the patient on postoperative antibiotics for an average of 9.4 days with an average duration of Kirschner wire fixation of 35.1 days. In the second case of a non-neuropathic diabetic patient, 18 surgeons (28%) indicated they would place the patient on postoperative antibiotics for an average of 13.8 days with an average duration of Kirschner wire fixation of 35.4 days. In the third case of a diabetic patient with neuropathy, 19 physicians (32%) indicated they would place the patient on postoperative antibiotics for an average of 14.5 days with an average duration of Kirschner wire fixation of 36.7 days. Few attending physicians at orthopedic foot and ankle fellowships placed their patients treated with percutaneous Kirschner wires on postoperative antibiotic prophylaxis, even in diabetic patients for whom an increased risk of infection has been documented. [Orthopedics. 2017; 40(4):e594-e597.].

Comparison of healing intra-articular fracture of distal femur using a Kirschner wire and autologous fibrin glue in an animal model.

Considering different surgical techniques for the fixation of osteochondral intra-articular fracture, the present study aimed to compare the efficacy of autologous fibrin glue and Kirschner wire (KW) on an osteochondral fracture in the left lateral condyle of Dutch rabbits with a control group. After 6 weeks, macroscopic and microscopic evaluation showed that autologous fibrin glue is easier and faster with a higher number of bone trabecula (P<0.05), whereas the healing rate and cellularity of the healing site were not different between the two groups (KW and glue). The use of autologous fibrin glue can be an alternative to KW fixation in the fixation of osteochondral fractures. LEVEL OF EVIDENCE: Level II.

Is there a clinical benefit of additional tension band wiring in plate fixation of the symphysis?

BACKGROUND: The purpose of this study was to determine whether additional tension band wiring in the plate for traumatic disruption of symphysis pubis has clinical benefits. Therefore, outcomes and complications were compared between a plate fixation group and a plate with tension band wiring group. METHODS: We retrospectively evaluated 64 consecutive patients who underwent open reduction and internal fixation of the symphysis pubis by using a plate alone (n = 39) or a plate with tension band wiring (n = 25). All the patients were followed up for a minimum of 24 months (mean, 34.4 months; range, 26-39 months). Demographic characteristics, outcomes, movement of the metal works, complications, revision surgery, and Majeed functional score were compared. RESULTS: Significant screw pullout was relatively significantly more frequently found in the plate fixation group than in the plate with tension band wiring group (P = 0.009). In terms of the overall rate of all-cause revision surgery, including significant loosening, symptomatic hardware, and patient-requested hardware removal during follow-up period, the plate with tension band wiring group showed a significantly lower rate. CONCLUSION: Tension band wiring in combination with a symphyseal plate showed better radiological outcomes, a lower incidence of hardware loosening, and a lower rate of revision surgery than plate fixation alone. This technique would have some potential advantages in terms of avoiding significant movement of plate, symptomatic hardware failure, and revision surgery.

Clinical outcomes and safety of distal biceps repair using a modified entry point.

BACKGROUND: The purpose of this study is to determine the safety of a one-incision technique for distal biceps repair with modified repair entry point in regards to the distance from the posterior interosseous nerve (PIN). Secondly, we present the clinical results of patients having undergone this procedure. METHODS: Ten cadaveric specimens were dissected to reveal the radial tuberosity. Two 1.6-mm guidewires were inserted into the radial tuberosity, one centrally, and one 5-mm more proximal. Both guidewires penetrated the dorsal cortex, and posterior dissection revealed their exit points. The distance from the PIN and each wire was determined using a vernier calliper. The functional outcomes of 10 patients' post repair were reviewed. Performance was determined using strength and range of motion (ROM) measurements. Functional impairment was assessed using the disability of the arm, shoulder and hand outcome measure (DASH score). The uninjured side was used as a control. RESULTS: The mean distance from the centre of the radial tuberosity to the PIN was 7.33 mm with a centrally placed wire, compared with 10.92 mm when measuring from the proximal guidewire (P < 0.05). Supination and flexion strengths were 83 and 90% of the uninjured side, respectively. There was a mean of 1.5° loss of flexion and 0° loss of extension. Loss of pronation and supination ROM were 0.5° and 4.5° on average, respectively. Average DASH score was 6.3. CONCLUSION: We recommend a 5-mm more proximal entry point for insertion of the guidewire during distal biceps repair. This poses less risk to the PIN without significant functional impairment. Our outcomes are comparable with those reported in the literature.

A retrospective study to validate an intraoperative robotic classification system for assessing the accuracy of kirschner wire (K-wire) placements with postoperative computed tomography classification system for assessing the accuracy of pedicle screw placements.

This purpose of this retrospective study is validation of an intraoperative robotic grading classification system for assessing the accuracy of Kirschner-wire (K-wire) placements with the postoperative computed tomography (CT)-base classification system for assessing the accuracy of pedicle screw placements.We conducted a retrospective review of prospectively collected data from 35 consecutive patients who underwent 176 robotic assisted pedicle screws instrumentation at Kaohsiung Medical University Hospital from September 2014 to November 2015. During the operation, we used a robotic grading classification system for verifying the intraoperative accuracy of K-wire placements. Three months after surgery, we used the common CT-base classification system to assess the postoperative accuracy of pedicle screw placements. The distributions of accuracy between the intraoperative robot-assisted and various postoperative CT-based classification systems were compared using kappa statistics of agreement.The intraoperative accuracies of K-wire placements before and after repositioning were classified as excellent (131/176, 74.4% and 133/176, 75.6%, respectively), satisfactory (36/176, 20.5% and 41/176, 23.3%, respectively), and malpositioned (9/176, 5.1% and 2/176, 1.1%, respectively)In postoperative CT-base classification systems were evaluated. No screw placements were evaluated as unacceptable under any of these systems. Kappa statistics revealed no significant differences between the proposed system and the aforementioned classification systems (P <0.001).Our results revealed no significant differences between the intraoperative robotic grading system and various postoperative CT-based grading systems. The robotic grading classification system is a feasible method for evaluating the accuracy of K-wire placements. Using the intraoperative robot grading system to classify the accuracy of K-wire placements enables predicting the postoperative accuracy of pedicle screw placements.

Augmentation by cerclage wire improves fixation of vertical shear femoral neck fractures-A biomechanical analysis.

BACKGROUND: Femoral neck fractures in young individuals are typically vertical shear fractures. These injuries are difficult to stabilize due to a significant varus displacement force across the hip with weight bearing. The purpose of this study was to evaluate the biomechanical stability offered by the addition of an augmented wire to conventional inverted triangle triple screw fixation for stabilizing vertical shear femoral neck fracture. METHODS: Sixteen medium 4th-generation synthetic composite femurs (Sawbones Pacific Research Laboratories, Vashon, WA) were divided into two groups. Vertical osteotomy was performed to mimic Pauwels III femoral neck fracture. Group A (n=8) was fixed with three parallel 6.5-mm cannulated screws (Stryker) with washer in inverted triangle configuration. In group B (n=8), all the screws were set using methods identical to group A, with the addition of the cerclage wire. Both groups were tested with nondestructive axial compression test at 7 and 25° of valgus stress, respectively. Then axial cyclic loading test with 1000N was applied for 1000 cycles, and interfragmentary displacement was measured with Fastrak magnetic tracking system (Polhemus, Colchester, VT, USA). Finally, destructive axial compression test was conducted at 7°of valgus stress. RESULTS: Axial stiffness showed that group B had a 66% increase (879N/mm vs. 1461N/mm, P<0.01) at 7° valgus and a 46% increase (1611N/mm vs. 2349N/mm, P<0.01) at 25° valgus in comparison with group A. Interfragmentary fracture displacement after cyclic loading was significantly less for group B compared with group A (0.34 vs 0.13mm, P=0.0016). For axial failure load, there was 42% increase in group B compared with group A (2602N/mm vs. 3686N/mm, P=0.0023). CONCLUSIONS: Our study demonstrates that the addition of a cerclage wire to inverted triangle triple screws provides substantial improvement in mechanical performance regarding fixation of vertically oriented femoral neck fractures when compared with the conventional construct. Our study provides support from a mechanical analysis perspective for the reported clinical usefulness of the cerclage wire.

Minimally invasive manipulative reduction with poking k-wire fixation in the treatment of various types of calcaneal fractures.

OBJECTIVE: The aim of this study is to investigate the safety and clinical efficacy of minimally invasive manipulative reduction with poking k-wire fixation in the treatment of various types of calcaneal fractures. PATIENTS AND METHODS: Between July 2012 and July 2014, a prospective parallel controlled study was conducted on 96 patients with closed calcaneal fractures who were admitted to our institution. These patients were randomly divided into two groups, with 48 in each group. Patients in plate group were treated using open reduction and internal fixation, whereas those of manipulation group were treated with minimally invasive manipulative reduction with poking k-wire fixation. All patients were followed up for six months to assess the postoperative recovery and complications. Kerr's scale was adopted to evaluate the functional recovery of fractured calcaneus. RESULTS: A mean healing duration of 9.48 ± 1.92 weeks was achieved in patients of plate group compared with a healing duration of 9.35 ± 1.66 weeks in those of manipulation group, with no statistical significance (p > 0.05). Complications occurred in 20 cases in plate group versus in seven cases in manipulation group with significant difference (p < 0.05). As for Sanders type II fracture, among patients with compression fracture and tongue type fracture, > 70% of patients achieved with excellent and good outcomes in both groups with no significant difference in clinical efficacy (p > 0.05). The rate of excellent and good outcomes in Sanders type III compression fractures was lower in manipulation group than in plate group (p < 0.05). As for Sanders type II fractures, the Kerr's score of tongue type fractures in manipulation group was higher than that in plate group, and comparison within manipulation group showed that the score of tongue type fractures was significantly higher than that of compression fractures (p < 0.05). However, as for Sanders type III fractures, the score of tongue type fractures in manipulation group was significantly higher than that in plate group, and the score of compression fractures in plate group was significantly higher than that in manipulation group (p < 0.05). CONCLUSIONS: Minimally invasive manipulative reduction with poking k-wire fixation is suitable for the treatment of Sanders type II tongue type and compression calcaneal fractures, as well as the treatment of Sanders type III tongue type fractures with several advantages, including easy operation, lower cost, fewer complications and favorable recovery.

A Novel Percutaneous Guide Wire (S-Wire) for Percutaneous Pedicle Screw Insertion: Its Development, Efficacy, and Safety.

PURPOSE: Minimally invasive spine stabilization (MISt) procedures, including MIS-transforaminal lumbar interbody fusion (MIS-TLIF), rely on precise placement of percutaneous pedicle screws (PPS). Serious intraoperative complications associated with PPS placement include great vessel and bowel injuries due to the guide-wire's anterior migration and penetration through the anterior aspect of the vertebral body. To address this issue, we developed a novel percutaneous guide wire (S-wire) and compared the biomechanical characteristics of S-wire and conventional wire in cadaveric spines, and to evaluate the S-wire's efficacy and safety in a clinical trial. METHODS: The S-wire is hollow, with braided wires extending at one tip. We compared the push-out and penetration forces of the S-wire and conventional wire in fresh cadaveric lumbar spines, from L1 to L5. RESULTS: Push-out forces caused the braided tip of the S-wire to bend or spread, and thus to resist anterior migration. The mean push-out forces for the S-wire and conventional wire were 15.5 ± 1.9 and 5.7 ± 0.8 N, respectively (P < .0001); the mean penetration forces were 69.1 ± 4.2 and 37.1± 4.8 N, respectively (P < .0005). There was no wire breakage or anterior-wall penetration in a clinical trial of 922 S-wires; interestingly, the pull-out force increased in 780 (84.6%) S-wires after placement. CONCLUSIONS: The mean push-out and penetration forces for the S-wire were approximately 3 and 2 times greater than those of conventional wire, respectively. The S-wire effectively prevented guide-wire anterior migration and penetration of the anterior vertebral-body wall. The S-wire device should effectively improve the safety of MISt procedures, including MIS-TLIF and percutaneous kyphoplasty in selected patient with osteoporosis.

Treatment of posttraumatic cubitus varus with corrective supracondylar humeral osteotomies using the methyl methacrylate external fixator.

BACKGROUND: In upper and lower extremity fractures and osteotomy fixation, the use of methyl methacrylate (MM) as an external fixator presents an alternative method. The primary aim of this retrospective study was to evaluate the midterm outcome of pediatric patients who underwent corrective humeral supracondylar lateral closing-wedge osteotomy, with the external fixation system composed of MM and multiplane K-wires. METHODS: Fourteen consecutive cases with cubitus varus, who underwent corrective osteotomy with a limited lateral approach stabilized with MM and the multiplane K-wires external fixator system between January 2006 and May 2010, were retrospectively evaluated. Time of union, preoperative and postoperative elbow range of motion, and humeroulnar angle were measured. Results were rated as excellent, good, or poor, according to Bellemore criteria. RESULTS: There were a total of 6 female patients and 8 male patients with a mean age of 5.7 years (range, 3 to 9 y). The mean follow-up period was 28.2 months (range, 24 to 48 mo). The mean humeroulnar angle was (-) 18.6 degrees preoperatively, and (+) 16.3 degrees at the final follow-up. Thirteen patients were evaluated as excellent and 1 patient as good, according to Bellemore criteria. Union was seen in all patients at mean 7 weeks (range, 6 to 8 wk). Pin tract infection was observed in 1 patient and treated with oral antibiotics. Loss of correction was not observed in any patient during follow-up. CONCLUSIONS: External fixation of corrective supracondylar humeral osteotomy with MM and multiplane K-wires is a practical, effective, reliable, and cheap alternative method that can be applied. LEVEL OF EVIDENCE: Level IV. Retrospective study.

Percutaneous pedicle screw placement with computer-navigated mapping in place of Kirschner wires: clinical article.

OBJECT: Percutaneous pedicle screw insertion techniques are commonly used to treat a variety of spinal disorders. Typically, Kirschner (K)-wires are used to guide the insertion of taps and screws during placement since the normal anatomical landmarks are not visualized. The use of K-wires adds risks, such as vascular and nerve injuries as well as increased radiation exposure given the use of fluoroscopy. The authors describe a series of patients who had percutaneous pedicle screws placed using a new computer-assisted navigation technique without the need for K-wires. METHODS: Minimally invasive percutaneous pedicle screw placement in the thoracic and lumbar spine was performed in a consecutive series of 15 patients for a variety of spinal pathologies. Intraoperative 3D CT images were obtained and used with a computer-assisted navigation system to insert an awl-tap into each pedicle. The tap location in the pedicle was marked with the navigation software, and the awl-tap was then removed. The navigation system was used to identify each landmark to insert the pedicle screw. Connecting rods were then inserted percutaneously under fluoroscopic guidance. Postoperative CT scans were obtained in each patient to evaluate screw placement. RESULTS: On postprocedure scanning, only 1 screw had a minor lateral and superior breach that was asymptomatic. To date, there have been no hardware failures. CONCLUSIONS: Percutaneous pedicle screws can be placed effectively and safely without the use of K-wires.

Digital arthrodesis.

For lesser toe deformities, fusion of the proximal interphalangeal joint offers good long-term correction and predictability. Digital arthrodesis has been described for longer than 100 years in the literature, and current techniques closely resemble those described in early accounts. However, many implants currently being used take advantage of the latest metallurgic and polymeric innovations, with implants being composed of nitinol, polylactic or polyglycolic acids, and polydioxanone. Newer implants offer easy insertion and good stability, with no percutaneous wires. Pin-tract infection rates from exposed Kirschner wires may be as high as 18%, and newer implants help to mitigate this problem.

Image guidance shortens the learning curve for K-wire placement - an experimental study.

BACKGROUND: Computer assisted systems in orthopaedic trauma depend in most cases on fixed reference markers. This work evaluated a reference-free image-based guidance system. Outcome parameters were the number of trials needed to achieve an optimal wire position, the radiation and procedure time, and the learning curve. METHODS: Forty artificial proximal femora covered in polyurethane foam were used and randomized in two groups. Each bone was equipped with a target marker at the fovea capitis femoris. Two surgeons each inserted 20 K-wires, 10 with and 10 without assistance from the guidance system. The aim was to bring the tips of the K-wires as close as possible to the target marker. Both procedures were performed under fluoroscopic control. The new guidance system is based on 2D-C-arm images. Following the procedure the result was determined using computed tomography. RESULTS: The same accuracy (P = 0.34) was achieved with less time (P = 0.0008) and less radiation (P = 0.0002) with the guidance system. However, use of the guidance system did shorten the learning curve of both surgeons, leading to a reduced number of trials (P <0.0001). The learning curve of both surgeons was strongly correlated. From the first trial, the performance of both surgeons while using the guidance system, improved over their performance without the guidance system. CONCLUSIONS: The guidance system helped to achieve an optimal K-wire position with less radiation and less time. The major advantage is the ability of the guidance system to be integrated into the workflow and the short and flat learning curve.