Fluoroscopic freehand and electromagnetic-guided targeting system for distal locking screws of humeral intramedullary nail

Purpose The current techniques used to lock distal screws for the nailing of long bone fractures expose the surgeons, radiologists and patients to a hearty dose of ionizing radiation. The Sureshot™ Distal Targeting System is a new technique that, with the same results, allows for shorter surgery times and, consequently, less exposure to radiation. Materials and methods The study was performed on 59 patients (34 males and 25 females) with a simple humerus fracture diagnosis, type 1.2.A according to the AO classification, who were divided into two groups. Group 1 was treated with ante-grade intramedullary nailing with distal locking screws inserted with a freehand technique. Group 2 was treated with the intramedullary nail using the Sureshot™ Distal Targeting System. Two intra-operative time parameters were evaluated in both groups: the time needed for the positioning of the distal locking screws and the time of exposure to ionizing radiations during this procedure. Results Group 2 showed a lower average distal locking time compared to group 1 (645.48″ vs. 1023.57″) and also a lower average time of exposure to ionizing radiation than in group 1 (4.35″ vs. 28.96″). Conclusion The Sureshot™ Distal Targeting System has proven to be equally effective when compared to the traditional techniques, with the added benefits of a significant reduction in both surgical time and risk factors related to the exposure to ionizing radiation for all the operating room staff and the patient

Is a Magnetic-Manual Targeting Device an Appealing Alternative for Distal Locking of Tibial Intramedullary Nails?

Background: In order to enable a radiation-free, accurate and simple positioning of distal locking screws, a combined magnetic and manual targeting system has been developed by Sanatmetal®. Where a low-frequency magnetic field is initially used to detect the position of the first drill hole and three more holes can be found with a mechanical template. Objectives: Our cadaver study was performed to evaluate the accuracy and efficiency of this device. Materials and Methods: In two runs, 30 probands (group 1: 10 students; group 2: 10 residents; group 3: 10 attendings), none of who being familiar with the device, tested the radiation-free system using 60 intact cadaver tibias. Each proband performed the surgical procedure twice in succession. Results: Referring to the first attempts, 9.6, 7.2 and 7.1 minutes were the time periods required to insert the four distal screws and the relevant values for the second attempts were 8.6, 6.3 and 6.2 minutes; in both cases revealing a significant difference between group 1 and 2 and group 1 and 3. Furthermore, the mean values within each group indicated a significant decrease of the test duration. Out of the 240 drillings, only one failure (group 1) occurred, representing an accuracy of 99.58 %. Of the probands, 90 % rated the targeting device better than the free-hand technique and 77 % at least attested a high user-friendliness. Conclusions: Due to our satisfactory test results, the brief training, the steep learning curve and the radiation-free technique the new device has to be considered an appealing alternative for distal locking

Validity of a Novel Digitally Enhanced Skills Training Station for Freehand Distal Interlocking.

Background and Objectives: Freehand distal interlocking of intramedullary nails is technically demanding and prone to handling issues. It requires precise placement of a screw through the nail under fluoroscopy guidance and can result in a time consuming and radiation expensive procedure. Dedicated training could help overcome these problems. The aim of this study was to assess construct and face validity of new Digitally Enhanced Hands-On Surgical Training (DEHST) concept and device for training of distal interlocking of intramedullary nails. Materials and Methods: Twenty-nine novices and twenty-four expert surgeons performed interlocking on a DEHST device. Construct validity was evaluated by comparing captured performance metrics-number of X-rays, nail hole roundness, drill tip position and drill hole accuracy-between experts and novices. Face validity was evaluated with a questionnaire concerning training potential and quality of simulated reality using a 7-point Likert scale. Results: Face validity: mean realism of the training device was rated 6.3 (range 4-7). Training potential and need for distal interlocking training were both rated with a mean of 6.5 (range 5-7), with no significant differences between experts and novices, p ≥ 0.234. All participants (100%) stated that the device is useful for procedural training of distal nail interlocking, 96% wanted to have it at their institution and 98% would recommend it to colleagues. Construct validity: total number of X-rays was significantly higher for novices (20.9 ± 6.4 versus 15.5 ± 5.3, p = 0.003). Success rate (ratio of hit and miss attempts) was significantly higher for experts (novices hit: n = 15; 55.6%; experts hit: n = 19; 83%, p = 0.040). Conclusion: The evaluated training device for distal interlocking of intramedullary nails yielded high scores in terms of training capability and realism. Furthermore, construct validity was proven by reliably discriminating between experts and novices. Participants indicate high further training potential as the device may be easily adapted to other surgical tasks

Open interlocked nailing without a targeting device or X-ray guidance for non-union of the femur: a case series

From October 2005 to August 2007, we operated on six patients who had femoral non-unions and performed interlocked intramedullary nailing without X-ray guidance or a targeting device. There were three fractures of the distal femur, two fractures of the mid-shaft and one of the proximal femur. Fatigue failure of a non-interlocked Kuntscher nail and one nail migration were the presenting features in two patients. The presence of sclerosis of the bone ends in four cases and a need for cancellous bone grafts at the site of non-union in all patients made wide dissection and open reduction unavoidable. There was a limb length discrepancy in all patients before surgical intervention. Partial weight bearing was commenced at 6 weeks post-operation. There was no case of wound infection. There was no misplaced screw. Minimum range of knee flexion was 105° at 2 months post-operation. These early results call for a closer look at this cheap, safe and effective means of handling femoral non-union in third world societies where there is paucity of instrumentation and implants for interlocked nailing

Reinforcing the role of the conventional C-arm - a novel method for simplified distal interlocking

<p>Abstract</p> <p>Background</p> <p>The common practice for insertion of distal locking screws of intramedullary nails is a freehand technique under fluoroscopic control. The process is technically demanding, time-consuming and afflicted to considerable radiation exposure of the patient and the surgical personnel. A new concept is introduced utilizing information from within conventional radiographic images to help accurately guide the surgeon to place the interlocking bolt into the interlocking hole. The newly developed technique was compared to conventional freehand in an operating room (OR) like setting on human cadaveric lower legs in terms of operating time and radiation exposure.</p> <p>Methods</p> <p>The proposed concept (guided freehand), generally based on the freehand gold standard, additionally guides the surgeon by means of visible landmarks projected into the C-arm image. A computer program plans the correct drilling trajectory by processing the lens-shaped hole projections of the interlocking holes from a single image. Holes can be drilled by visually aligning the drill to the planned trajectory. Besides a conventional C-arm, no additional tracking or navigation equipment is required.</p> <p>Ten fresh frozen human below-knee specimens were instrumented with an Expert Tibial Nail (Synthes GmbH, Switzerland). The implants were distally locked by performing the newly proposed technique as well as the conventional freehand technique on each specimen. An orthopedic resident surgeon inserted four distal screws per procedure. Operating time, number of images and radiation time were recorded and statistically compared between interlocking techniques using non-parametric tests.</p> <p>Results</p> <p>A 58% reduction in number of taken images per screw was found for the guided freehand technique (7.4 ± 3.4) (mean ± SD) compared to the freehand technique (17.6 ± 10.3) (<it>p </it>< 0.001). Total radiation time (all 4 screws) was 55% lower for the guided freehand technique compared to conventional freehand (<it>p </it>= 0.001). Operating time per screw (from first shot to screw tightened) was on average 22% reduced by guided freehand (<it>p </it>= 0.018).</p> <p>Conclusions</p> <p>In an experimental setting, the newly developed guided freehand technique for distal interlocking has proven to markedly reduce radiation exposure when compared to the conventional freehand technique. The method utilizes established clinical workflows and does not require cost intensive add-on devices or extensive training. The underlying principle carries potential to assist implant positioning in numerous other applications within orthopedics and trauma from screw insertions to placement of plates, nails or prostheses.</p

X-ray-based machine vision system for distal locking of intramedullary nails

In surgical procedures for femoral shaft fracture treatment, current techniques for locking the distal end of intramedullary nails, using two screws, rely heavily on the use of two-dimensional X-ray images to guide three-dimensional bone drilling processes. Therefore, a large number of X-ray images are required, as the surgeon uses his/her skills and experience to locate the distal hole axes on the intramedullary nail. The long-term effects of X-ray radiation and their relation to different types of cancer still remain uncertain. Therefore, there is a need to develop a surgical technique that can limit the use of X-rays during the distal locking procedure. A robotic-assisted orthopaedic surgery system has been developed at Loughborough University to assist orthopaedic surgeons by reducing the irradiation involved in such operations. The system simplifies the current approach as it uses only two near-orthogonal X-ray images to determine the drilling trajectory of the distal locking holes, thereby considerably reducing irradiation to both the surgeon and patient. Furthermore, the system uses robust machine vision features to reduce the surgeon's interaction with the system, thus reducing the overall operating time. Laboratory test results have shown that the proposed system is very robust in the presence of variable noise and contrast in the X-ray images

X-ray based machine vision system for distal locking of intramedullary nails

In surgical procedures for femoral shaft fracture treatment, current techniques for locking the distal end of intramedullary nails, using two screws, rely heavily on the use of two-dimensional X-ray images to guide three-dimensional bone drilling processes. Therefore, a large number of X-ray images are required, as the surgeon uses his/her skills and experience to locate the distal hole axes on the intramedullary nail. The long-term effects of X-ray radiation and their relation to different types of cancer still remain uncertain. Therefore, there is a need to develop a surgical technique that can limit the use of X-rays during the distal locking procedure. A Robotic-Assisted Orthopaedic Surgery System has been developed at Loughborough University named Loughborough Orthopaedic Assistant System (LOAS) to assist orthopaedic surgeons during distal-locking of intramedullary nails. It uses a calibration frame and a C-arm X-ray unit. The system simplifies the current approach as it uses only two near-orthogonal X-ray images to determine the drilling trajectory of the distal-locking holes, thereby considerably reducing irradiation to both the surgeon and patient. The LOAS differs from existing computer-assisted orthopaedic surgery systems, as it eliminates the need for optical tracking equipment which tends to clutter the operating theatre environment and requires care in maintaining the line of sight. Additionally use of optical tracking equipment makes such systems an expensive method for surgical guidance in distal-locking of intramedullary nails. This study is specifically concerned with the improvements of the existing system. [Continues.

Prospective and Retrospective analysis of Functional Outcome of Distal both bone Leg Fracture treated with Tibial Interlocking Nailing with and without Fibular plating: Comparative study

AIM AND OBJECTIVE: To analyse the functional outcome of distal both bone leg fractures treated with Tibial Interlocking nail with and without supplementary fibular plating. MATERIALS AND METHODS: This is a prospective and retrospective study of 20 patients distal both bone leg fractures– 10 patients treated with interlocking nailing alone and 10 patients treated with interlocking nailing with supplementary fibular plating. The study was done after getting clearance from Hospital ethical committee. Those who fulfilled the inclusion criteria given below, were invited to participate in the study. Informed consent was obtained from all the patients willing to take part in the study. OUTCOME: Alignment and reduction preoperatively, postoperatively and at healing was the main outcome measured with an emphasis on loss of initial reduction on follow up. Fibular plating Fibular plating was selected for the following reasons, 1. correction of alignment before insertion of nail. 2. Maintaining the alignment or to improve the stability of bone implant complex. 3. For achieving rotational stability. Kalstrom-Olerud score was used to assess the functional outcome. It is an independent measurement, not influenced by other co-morbid conditions and associated injuries. RESULTS: All the relevant data were analysed. The Fractures treated with tibial interlocking nailing without fibular plating were analysed and 5 (50%) cases were malunited and deformed. Karlstrom- Olerud scoring was excellent in one (10%) patient, good in 5 Patients (50%), fair in 3 (30%) patients and poor in 1 (10 %) patients. The mean delay in surgery for this group is 2.2 weeks. Radiologically the mean post operative varus/valgus alignment was 8.6 degrees. The mean duration of time of union is 12.70 weeks. 4 patients needed cast support. The average follow up is 8 months( lowest – 4 months , longest – 18 months). All the fractures treated with supplementary fibular plating in addition to tibial interlocking nailing eventullay united in a mean period of 11.60 weeks Karlstrom-Olerud score was excellent in 6 fractures (60%), good in 3 patients (30%) and fair in 1 patient (10%) The mean delay between the injury and the surgery was 1.8 weeks. Radiologically the mean post operative varus/valgus alignment was 2.10 degrees. The alignment was maintained till union with the mean remaining the same in the coronal plane. The average follow up is 10.3 months (lowest- 6 months, longest – 24 months). The p value for varus/ valgus angulation with equal variances assumed is 0.0016 and with equal variances not assumed is 0.0064. Thus it is statistically significant that the p- value is < 0.05. The p- value for time of union is 0.3425( p value >0.05), so it is statistically insignificant. CONCLUSION: We conclude that fibular plating, when supplemented the intramedullary nailing of distal both bone fractures of leg, 1. Were effective in achieving the fracture alignment especially in fresh fractures. 2. Improves not only angular stability but also rotational stability. 3. Maintained the fracture alignment till union, preventing loss of initial Reduction

Fluoroscopy-based navigation system in spine surgery

The variability in width, height, and spatial orientation of a spinal pedicle makes pedicle screw insertion a delicate operation. The aim of the current paper is to describe a computer-assisted surgical navigation system based on fluoroscopic X-ray image calibration and three-dimensional optical localizers in order to reduce radiation exposure while increasing accuracy and reliability of the surgical procedure for pedicle screw insertion. Instrumentation using transpedicular screw fixation was performed: in a first group, a conventional surgical procedure was carried out with 26 patients (138 screws); in a second group, a navigated surgical procedure (virtual fluoroscopy) was performed with 26 patients (140 screws). Evaluation of screw placement in every case was done by using plain X-rays and post-operative computer tomography scan. A 5 per cent cortex penetration (7 of 140 pedicle screws) occurred for the computer-assisted group. A 13 per cent penetration (18 of 138 pedicle screws) occurred for the non computer-assisted group. The radiation running time for each vertebra level (two screws) reached 3.5 s on average in the computer-assisted group and 11.5 s on average in the non computer-assisted group. The operative time for two screws on the same vertebra level reaches 10 min on average in the non computer-assisted group and 11.9 min on average in the computer-assisted group. The fluoroscopy-based (two-dimensional) navigation system for pedicle screw insertion is a safe and reliable procedure for surgery in the lower thoracic and lumbar spine

Radiological and Functional Outcome of Retrograde Nailed Humeral Diaphyseal Fracture

INTRODUCTION: Of all fracture of upper limb, the fracture shaft of humerus is relatively common and easiest to treat. Fracture shaft of humerus accounts for 1% of all adult fractures. There is wide array of good options for their treatment and there is controversy over best methods for many situations. Appropriate decision making for non-operative or operative treatment depends on a thorough understanding of regional anatomy, fracture pattern (Personality of fracture), Classification and finally factors unique to patient (Personality of patient). AIM: To study and analyse radiological union, functional outcome and complications of retrograde unreamed intramedullary interlocking nailing for treating acute humeral diaphyseal fractures in adults. MATERIALS AND METHODS: Our prospective study was from April 2004 to Feb 2006. At our institution, we selected 19 cases of diaphyseal fractures of humerus for this prospective study. All fresh fractures of the humeral shaft chosen for operative treatment including isolated fractures and those in polytrauma patients were nailed in retrograde manner. When there were no clear indications for operative treatment patients were asked for informed consent for retrograde nailing. RESULTS: Out of the 19 patients evaluated, The average hospital stay was 19 days and the mean healing time of a all fractures was 13.74 weeks. Patients with isolated lesions were in hospital for a mean of 14 days. At review, shoulder function was excellent in 17 patients, good in one patient, fair in one patient, no one in poor grade. Elbow function was excellent in 14 patients, good in 3 patients, two in fair grade, no one in poor grade. Total functional out come was excellent in 84% patients, good in 7.8% patients, fair in 6.5% patient poor grade in 1.31% patient. CONCLUSION: The concept of biological fixation in terms of unreamed nailing, closed reduction, static locking and fracture site compression promotes early and adequate fracture union. The problem of shoulder impingement and peri-arthritis shoulder, rotator cuff injury in ante grade nailing are completely avoided with good functional outcome. It helps in providing early rehabilitation and lessens the morbidity. Retrograde humeral nailing is better than anterograde nailing and alternative to plate osteosynthesis for patients with indications for the operative treatment of fractures of the humeral shaft. Retrograde nailing is an attractive option in polytrauma, for isolated fractures which would be difficult to treat conservatively and for patients who require a rapid functional recovery