First 100 total hip arthroplasties performed by a young surgeon using the direct anterior approach: learning curve and complications.

INTRODUCTION: Most of the reported discussions about the learning curve for the direct anterior approach (DAA) in total hip arthroplasty (THA) have been by experienced surgeons. The study's aim was to describe the learning curve, short-term outcomes, complications, and adaptations to the DAA used in the first 100 THA cases experienced by a young surgeon who had received DAA training for trauma surgeries. MATERIALS AND METHODS: This retrospective study summarizes the first 100 consecutive cases experienced by a young surgeon who performed the unilateral DAA for THA between 2019 and 2021. Cumulative sum (CUSUM) analysis was performed to evaluate the learning curve on the basis of operative time and overall complications. The demographics data, short-term outcomes, and complications of the first 50 and second 50 cases were compared. RESULTS: The CUSUM curve declined after 49 and 55 cases, measured by operative time and overall complications, respectively. The median operative time (104 vs. 80 min) and intraoperative fluoroscopic time (38 vs. 12 s) increased significantly in the first 50 cases compared with the times in the second 50 cases. Complications tended to occur in the first 50 cases (12% vs. 6%), and the overall rate was 9%. Major complications all occurred in the first 50 cases, with a rate of 4%. Only one case, which involved a complicated periprosthetic fracture around the stem that extended to the tip, required the intervention of a senior surgeon. CONCLUSIONS: Even after receiving training on the DAA for trauma surgeries, the young surgeon experienced a steep learning curve and more complications in the first 50 cases. The DAA for THA is a technically demanding procedure and may require guidance from an experienced surgeon to manage unexpected complications.

Does an Internal Joint Stabilizer and Standardized Protocol Prevent Recurrent Instability in Complex Persistent Elbow Instability?

BACKGROUND: The treatment of complex persistent elbow instability after trauma is challenging. Previous studies on treatments have reported varied surgical techniques, which makes it difficult to establish a therapeutic algorithm. Furthermore, the surgical procedures may not sufficiently restore elbow stability, even with an additional device, and a noted high rate of arthritis progression.While a recently developed internal joint stabilizer effectively treats elbow instability, its clinical application for complex persistent elbow instability is limited and the standardized protocol is not well described. Additionally, we want to know whether the arthritis progression will cause a negative impact on the functional outcomes of complex persistent elbow instability. QUESTIONS/PURPOSES: (1) Does treatment of complex persistent elbow instability with a hinged internal joint stabilizer and a standardized protocol prevent recurrent instability and other complications? (2) What are the pre- to postoperative improvements in pain, disability, elbow performance, and ROM? (3) Is the development of post-traumatic arthritis associated with worse pain, disability, elbow performance, and ROM? METHODS: Between September 2014 and October 2019, we treated 22 patients for persistent dislocation or subluxation after initial treatment of traumatic elbow fracture-dislocations. Of those, we considered patients who were at least 20 years of age, with an interval of 6 weeks or more between the injury (initial treatment) and the index reconstructive procedure, which had been performed at our institute, as potentially eligible. During that time, we used an internal joint stabilizer with a standardized protocol for posttraumatic complex persistent elbow instability. We performed total elbow replacements in patients older than 50 years who had advanced elbow arthritis. Based on that, 82% (18 of 22) of patients were eligible; 14% (3 of 22) were excluded because total elbow replacements was undertaken, and another 5% (1 of 22) were lost before the minimum study follow-up of 1 year (median 24 months [range 12 to 63]), leaving 64% (14 of 22) for analysis in this retrospective study. We treated 14 patients (14 elbows) with posttraumatic complex persistent elbow instability with an internal joint stabilizer and a standardized protocol that comprised debridement arthroplasty with ulnar neurolysis, restoration of bony and ligamentous (reattachment) structures, application of an internal joint stabilizer, and early rehabilitation. There were eight men and six women in this study, with a median (range) age of 44 years (21 to 68). The initial elbow fracture-dislocation injury pattern was a terrible triad injury in seven patients, a posterolateral rotatory injury in four patients, and a posterior Monteggia fracture in three patients. Preoperative and follow-up radiographs were reviewed for evidence of recurrent instability and arthritis. Complications such as wound infection, seroma, neurovascular injury, and hardware complications were ascertained through chart review. Preoperative and postoperative VAS score for pain, DASH, and Mayo Elbow Performance Scores (MEPS) were collected and compared. Furthermore, extension-flexion and supination-pronation arcs were collected by chart review. We divided the patients into two groups according to whether or not they developed posttraumatic arthritis. We then presented the differences between pain, disability, elbow performance, and ROM. The hinged internal joint stabilizer was removed using another open procedure under general anesthesia 6 to 8 weeks after surgery. RESULTS: There were no recurrent instability during and after device removal. Seven patients developed complications, including wound infection, seroma, neurovascular injury, hardware complications, and heterotopic ossification. Two patients had complications related to internal joint stabilizers and three had complications linked to radial head prostheses. Median (range) preoperative to postoperative changes included decreased pain (VAS 5 [2 to 9] to 0 [0 to 3], difference of medians -5; p < 0.001), decreased disability (DASH 41 [16 to 66] to 7 [0 to 46], difference of medians -34; p < 0.001), improved function (MEPS 60 [25 to 70] to 95 [65 to 100], difference of medians 35; p < 0.001), improved extension-flexion arc (40° [10° to 70°] to 113° [75° to 140°], difference of medians 73°; p < 0.001), and supination-pronation arc (78° [30° to 165°] to 148° [70° to 175°], difference of medians 70°; p < 0.001). Between patients with and without development of post-traumatic arthritis, there were no differences in postoperative pain (VAS 0 [0 to 3] to 0 [0 to 1], difference of medians 0; p = 0.17), disability (DASH 7 [0 to 46] to 7 [0 to 18], difference of medians 0; p = 0.40), function (MEPS 80 [65 to 100] to 95 [75 to 100], difference of medians 15; p = 0.79), extension-flexion arc (105° [75° to 140°] to 115° [80° to 125°], difference of medians 10°; p = 0.40), and supination-pronation arc (155° [125° to 175°] to 135° [70° to 160°], difference of medians -20°; p < 0.18). CONCLUSION: In this small, retrospective study, we found that an internal joint stabilizer with a standardized treatment protocol could maintain concentric reduction while allowing early functional motion, and that it could improve clinical outcomes for patients with complex persistent elbow instability. However, patients must be counseled that the complications related to the radial head prostheses may occur, and that the benefits of early motion must compensate for an additional removal procedure and the risk of seroma formation. LEVEL OF EVIDENCE: Level IV, therapeutic study.

A cost and efficacy analysis of performing arthroscopic excision of wrist ganglions under wide-awake anaesthesia versus general anaesthesia.

BACKGROUND: Arthroscopic excision has currently become popular for the treatment of wrist ganglions. The objective of this study was to evaluate the clinical outcomes and cost effectiveness of arthroscopic wrist ganglion excisions under Wide-Awake Local Anaesthesia No Tourniquet versus general anaesthesia. METHODS: We retrospectively reviewed patients who underwent arthroscopic ganglionectomy from April 2009 to October 2016 at our institute. They were separated into two groups according to anaesthesia techniques: general anaesthesia and Wide-Awake Local Anaesthesia No Tourniquet. We compared the clinical outcomes and cost-effectiveness of the two groups. RESULTS: Seventy-four patients were included. Both groups were matched with regard to the demographics and preoperative clinical assessments. We found no significant differences between groups in postoperative visual analog scale, modified Mayo wrist score, Disabilities of Arm, Shoulder and Hand score, recurrence, residual pain, or complications. Recurrence was found in five of 74 patients, one (4.3%) in the Wide-Awake Local Anaesthesia No Tourniquet group and four (7.8%) in the general anaesthesia group. One extensor tendon injury and four extensor tenosynovitis cases occurred in the general anaesthesia group. Regarding cost effectiveness, the mean operating time in the Wide-Awake Local Anaesthesia No Tourniquet and general anaesthesia groups were 88.7 ± 24.51 and 121.5 ± 25.75 min, respectively (p < 0.001). The average total costs of the Wide-Awake Local Anaesthesia No Tourniquet and general anaesthesia groups were €487.4 ± 89.15 and €878.7 ± 182.13, respectively (p < 0.001). CONCLUSIONS: For arthroscopic wrist ganglion resections, both anaesthesia techniques were effective and safe regarding recurrence rates, complications, and residual pain. The most important finding of this study was that arthroscopic ganglionectomy under Wide-Awake Local Anaesthesia No Tourniquet was superior to that under general anaesthesia for cost-effectiveness. LEVEL OF EVIDENCE: Level III, Retrospective comparative study.

Intramedullary cortical bone strut improves the cyclic stability of osteoporotic proximal humeral fractures.

BACKGROUND: Proximal humeral fractures treated with locking plate can fail due to varus collapse, especially in osteoporotic bone with medial cortex comminution. The use of an intramedullary strut together with locking plate fixation may strengthen fixation and provide additional medial support to prevent the varus malalignment. This study biomechanically investigates the influence of an intramedullary cortical bone strut on the cyclic stability of proximal humeral fractures stabilized by locking plate fixation in a cadaver model. METHODS: Ten cadaveric humeri were divided into two groups statistically matched for bone density. Each specimen was osteotomized with 10 mm gap at the surgical neck. The non-augmented group stabilized with locking plate alone; in the augmented group, a locking plate was used combined with an intramedullary cortical bone strut. The strut was retrograded into the subchondral bone, and three humeral head screws were inserted into the strut to form a plate-screw-strut mechanism. The cyclic axial load was performed to 450 N for 6000 cycles and then loaded to failure. Construct stiffness, cyclic loading behavior and failure strength were analyzed to identify differences between groups. RESULTS: The augmented constructs were significantly stiffer than the non-augmented constructs during cycling. On average, the maximum displacements at 6000 cycles for non-augmented and augmented groups were 3.10 ± 0.75 mm and 1.7 ± 0.65 mm (p = 0.01), respectively. The mean peak-to-peak (inter cycle) displacement at 6000 cycles was about 2 times lower for the augmented group (1.36 ± 0.68 mm vs. 2.86 ± 0.51 mm). All specimens showed varus collapse combined with loss of screw fixation of the humeral head. The failure load of the augmented group was increased by 2.0 (SD = 0.41) times compared with the non-augmented group (p < 0.001). CONCLUSIONS: The stability and strength of the locking plate augmented with an intramedullary strut were significantly increased. For bone with poor quality, the subsidence of the locked screws led larger displacement, decreased the stability of the constructs, however, the plate-screw-strut mechanism provided more rigidity to stabilize the fixation. This study emphasized the importance of intramedullary support for the proximal humeral fractures fixed with a locked plate under cyclic loading, especially in bone with poor quality. This work is based on the results of cadaver model, further in vivo analysis is necessary to determine if the clinical results can be extrapolated from this data.

Three-stage treatment protocol for recalcitrant distal femoral nonunion.

INTRODUCTION: In this study, we proposed a three-stage treatment protocol for recalcitrant distal femoral nonunion and aimed to analyze the clinical results. MATERIALS AND METHODS: We retrospective reviewed 12 consecutive patients with recalcitrant distal femoral nonunion undergoing our three-stage treatment protocol from January 2010 to December 2014 in our institute. The three-stage treatment protocol comprised debridement of the nonunion site, lengthening to eliminate leg length discrepancy, deformity correction, stabilization with a locked plate, filling of the defect with cement spacer for inducing membrane formation, and bone reconstruction using a cancellous bone autograft (Masquelet technique) or free vascularized fibular bone graft. The bone union time, wound complication, lower limbs alignment, amount of lengthening, knee range of motion, and functional outcomes were evaluated. RESULTS: Osseous union with angular deformity <5° and leg length discrepancy <1 cm were achieved in all the patients. The average amount of lengthening was 5.88 cm (range 3.5-12 cm). Excellent or good outcomes were obtained in 9 patients. CONCLUSIONS: Although the current study involved only a small number of patients and the intervention comprised three stages, we believe that such a protocol may be a valuable alternative for the treatment of recalcitrant distal femoral nonunion.

Dumontier group 2 radiocarpal fracture-dislocation: The results of open reduction and fixation without volar ligament repair.

INTRODUCTION: The radiocarpal fracture-dislocations are a spectrum of severe injury involving both the bony and ligamentous structures that stabilise the wrist joint. The aim of this study was to analyse the outcome of open reduction and fixation without volar ligament repair for Dumontier group 2 radiocarpal fracture-dislocation and to evaluate the incidence and clinical relevance of ulnar translation and advanced osteoarthritis. PATIENTS AND METHODS: We retrospectively reviewed 22 patients with Dumontier group 2 radiocarpal fracture-dislocation treated in our institute. Clinical and radiological outcomes were recorded. Postoperative visual analogue scale (VAS) score for pain, Disabilities of the Arm, Shoulder and Hand Outcome Measure (DASH), and Mayo modified wrist scores (MMWS) were collected. Furthermore, extension‒flexion and supination‒pronation arcs were collected by reviewing chart, either. We divided the patients into two groups according to the presence or absence of advanced osteoarthritis, and presented the differences in the pain, disability, wrist performance, and range of motion between the two groups. We performed the same comparison between the patients with and those without the ulnar translation of the carpus. RESULTS: There were sixteen men and six women with a median age of 23 years (range, 20‒48 years). The median follow-up period was 33 months (range, 12-149 months). The median VAS, DASH and MMWS were 0 (range 0-2), 9.1 (range, 0-65.9) and 80 (range, 45-90), respectively. The median flexion‒extension and pronation‒supination arcs were 142.5° (range, 20°â€’170°) and 147.5° (range, 70°â€’175°), respectively. Ulnar translation was recognised in four patients and the development of advanced osteoarthritis was noted in 13 patients during the follow-up period. However, neither was highly correlated with functional outcomes. CONCLUSION: The current study postulated that ulnar translation might occur following treatment for Dumontier group 2 lesions, whereas injury was predominantly caused by rotational force. Therefore, radiocarpal instability should be recognized during the operation. However, the clinical relevance of ulnar translation and wrist osteoarthritis needs to be assessed in further comparison studies.

Cyclic Stability of Locking Plate Augmented with Intramedullary Polymethyl Methacrylate (PMMA) Strut Fixation for Osteoporotic Humeral Fractures: A Biomechanical Study.

The locking plate may provide improved fixation in osteoporotic bone; however, it has been reported to fail due to varus collapse or screw perforation of the articular surface, especially in osteoporotic bone with medial cortex comminution. Using bone graft as an intramedullary strut together with plate fixation may result in a stronger construct. However, the drawbacks of bone grafts include limited supply, high cost, and infection risk. PMMA (so-called bone cement) has been widely used for implant fixation due to its good mechanical properties, fabricability, and biocompatibility. The risk of donor-site infection and the drawbacks of allografting may be overcome by considering PMMA struts as alternatives to fibular grafts for humeral intramedullary grafting surgeries. However, the potential effects of intramedullary PMMA strut on the dynamic behaviour of osteoporotic humerus fractures remain unclear. This study aimed to investigate the influence of an intramedullary PMMA strut on the stability of unstable proximal humeral fractures in an osteoporotic synthetic model. Two fixation techniques, a locking plate alone (non-strut group) and the same fixation augmented with an intramedullary PMMA strut (with-strut group), were cyclically tested in 20 artificial humeral models. Axially cyclic testing was performed to 450 N for 10,000 cycles, intercyclic motion, cumulated fragment migration, and residual deformation of the constructs were determined at periodic cyclic intervals, and the groups were compared. Results showed that adding an intramedullary PMMA strut could decrease 1.6 times intercyclic motion, 2 times cumulated fracture gap migration, and 1.8 times residual deformation from non-strut fixation. During cycling, neither screw pull-out, cut-through, nor implant failure was observed in the strut-augmented group. We concluded that the plate-strut mechanism could enhance the cyclic stability of the fixation and minimize the residual displacement of the fragment in treating osteoporotic proximal humeral unstable fractures. The PMMA strut has the potential to substitute donor bone and serve as an intramedullary support when used in combination with locking plate fixation. The intramedullary support with bone cement can be considered a solution in the treatment of osteoporotic proximal humeral fractures, especially when there is medial comminution.

A comprehensive painkillers screening by assessing zebrafish behaviors after caudal fin amputation.

Recently, the usage of zebrafish for pain studies has increased in the past years, especially due to its robust pain-stimulated behaviors. Fin amputation has been demonstrated to induce a noxious response in zebrafish. However, based on the prior study, although lidocaine, the most used painkiller in zebrafish, has been shown to ameliorate amputated zebrafish behaviors, it still causes some prolonged effects. Therefore, alternative painkillers are always needed to improve the treatment quality of fin-amputated zebrafish. Here, the effects of several analgesics in recovering zebrafish behaviors post-fin amputation were evaluated. From the results, five painkillers were found to have potentially beneficial effects on amputated fish behaviors. Overall, these results aligned with their binding energy level to target proteins of COX-1 and COX-2. Later, based on their sub-chronic effects on zebrafish survivability, indomethacin, and diclofenac were further studied. This combination showed a prominent effect in recovering zebrafish behaviors when administered orally or through waterborne exposure, even with lower concentrations. Next, based on the ELISA in zebrafish brain tissue, although some changes were found in the treated group, no statistical differences were observed in most of the tested biomarkers. However, since heatmap clustering showed a similar pattern between biochemical and behavior endpoints, the minor changes in each biomarker may be sufficient in changing the fish behaviors.

Radiographic and clinical results of posterior dynamic stabilization for the treatment of multisegment degenerative disc disease with a minimum follow-up of 3 years.

BACKGROUND: This study aims to compare radiographic and clinical outcomes of Dynesys and posterior lumbar interbody fusion (PLIF) for the treatment of multisegment disease. METHODS: Thirty-five consecutive patients who received Dynesys implantation at three levels from L1 to S1 from November 2006 to July 2007 were studied. A retrospective analysis of the medical records of 25 patients with the same indications who received 3-level PLIF (L1-S1) was also conducted. Radiographic and clinical outcomes between the groups were compared. All patients included in the analysis completed 3-year follow-up. Dynesys stabilization resulted in higher preservation of motion at the operative levels, as well as total range of motion from L1 to S1. A decrease of anterior disc height was seen in the Dynesys group and an increase was seen in the PLIF group. An increase in posterior disc height was noted in both groups; however, was greater in the PLIF group at 3 years. RESULTS: The Dynesys group showed a greater improvement in Oswestry Disability Index and visual analogue scale back pain scores at 3 years postoperatively. There were no differences in complications between the two groups. CONCLUSION: In conclusion, Dynesys is an acceptable alternative to PLIF for the treatment of multisegment lumbar disease.

Comparison of Dynesys posterior stabilization and posterior lumbar interbody fusion for spinal stenosis L4L5.

The aim of this prospective randomized study was to compare the radiological and clinical outcome after treatment of lumbar spinal stenosis L4L5 with or without spondylolisthesis, with either posterior lumbar interbody fusion (PLIF) (26 patients) or Dynesys posterior stabilization (27 patients). Demographic characteristics were comparable in both groups. Dynesys stabilization resulted in significantly higher preservation of motion at the index level (p < 0.001), and significantly less (p < 0.05) hypermobility at the adjacent segments. Oswestry Disability Index (ODI) and VAS for back and leg pain improved significantly (p < 0.05) with both methods, but there was no significant difference between groups. Operation time, blood loss, and length of hospital stay were all significantly (p < 0.001) less in the Dynesys group. The latter benefits may be of particular importance for elderly patients, or those with significant comorbidities. Complications were comparable in both groups. Dynesys posterior stabilization was effective for treating spinal stenosis L4L5 with or without spondylolisthesis.

Biomechanical Effect of Hybrid Dynamic Stabilization Implant on the Segmental Motion and Intradiscal Pressure in Human Lumbar Spine.

The hybrid dynamic stabilization system, Dynesys-Transition-Optima, represents a novel pedicle-based construct for the treatment of lumbar degenerative disease. The theoretical advantage of this system is to stabilize the treated segment and preserve the range of motion within the adjacent segment while potentially decreasing the risk of adjacent segment disease following lumbar arthrodesis. Satisfactory short-term outcomes were previously demonstrated in the Dynesys-Transition-Optima system. However, long-term follow-up reported accelerated degeneration of adjacent segments and segmental instability above the fusion level. This study investigated the biomechanical effects of the Dynesys-Transition-Optima system on segment motion and intradiscal pressure at adjacent and implanted levels. Segmental range of motion and intradiscal pressure were evaluated under the conditions of the intact spine, with a static fixator at L4-5, and implanted with DTO at L3-4 (Dynesys fixator) and L4-5 (static fixator) by applying the loading conditions of flexion/extension (±7.5 Nm) and lateral bending (±7.5 Nm), with/without a follower preload of 500 N. Our results showed that the hybrid Dynesys-Transition-Optima system can significantly reduce the ROM at the fusion level (L4-L5), whereas the range of motion at the adjacent level (L3-4) significantly increased. The increase in physiological loading could be an important factor in the increment of IDP at the intervertebral discs at the lumbar spine. The Dynesys-Transition-Optima system can preserve the mobility of the stabilized segments with a lesser range of motion on the transition segment; it may help to prevent the occurrence of adjacent segment degeneration. However, the current study cannot cover all the issues of adjacent segmental diseases. Future investigations of large-scale and long-term follow-ups are needed.

Associations between emotional intelligence and doctor burnout, job satisfaction and patient satisfaction.

CONTEXT: The occupational health literature has long been dominated by stress-related topics. A more contemporary perspective suggests using a positive approach in the form of a health model focused on what is right with people, such as feelings of well-being and satisfaction. OBJECTIVES: Using a positive perspective and multi-source data collection, this study investigated the inter-relationships among emotional intelligence (EI), patient satisfaction, doctor burnout and job satisfaction. METHODS: In this observational study, 110 internists and 2872 out-patients were surveyed in face-to-face interviews. RESULTS: Higher self-rated EI was significantly associated with less burnout (p<0.001) and higher job satisfaction (p<0.001). Higher patient satisfaction was correlated with less burnout (p<0.01). Less burnout was found to be associated with higher job satisfaction (p<0.001). CONCLUSIONS: This study identified EI as a factor in understanding doctors' work-related issues. Given the multi-dimensional nature of EI, refinement of the definition of EI and the construct validity of EI as rated by others require further examination.

Locked plating for proximal humeral fractures: differences between the deltopectoral and deltoid-splitting approaches.

BACKGROUND: Locking proximal humerus plate (LPHP) fixation has recently become available for the treatment of proximal humeral fractures. However, the preliminary results were contradictory. The technical requirements for success when using LPHP remain to be defined. Maybe the approach to the proximal humerus plays an important role, not the implants. We analyzed two surgical approaches to proximal humeral fractures. METHODS: Between April 2004 and October 2007, 63 consecutive patients with displaced proximal humeral fractures who underwent LPHP osteosynthesis in our institute were classified to two treatment groups retrospectively: the deltopectoral incision and the deltoid-splitting incision according to surgeon's preference. The Constant and Disabilities of the Arm, Shoulder and Hand scores were recorded for clinical assessment. Quality of reduction, fracture union, and radiographic complications were recorded for radiographic assessment. Electrophysiological abnormalities were also assessed. RESULTS: There were no significant differences between the groups with regard to demographic data, preoperative radiographic findings, and duration of follow-up. There were also no significant differences between the groups with regard to operative time (p = 0.918), blood loss (p = 0.407), hospital stay (p = 0.431), postoperative head-shaft angle (p = 0.769), union time (p = 0.246), final head-shaft angle (p = 0.533), Constant score (p = 0.677), Disabilities of the Arm, Shoulder and Hand score (p = 0.833), radiographic complications (p = 1.000), and presence of electrophysiological abnormalities (p = 0.296). Avascular necrosis of the humeral head was found in three patients, all of whom in the deltopectoral approach group. CONCLUSION: We found no statistically significant difference in clinical, radiographic, and electrophysiological outcomes between the deltopectoral approach and deltoid-splitting approach while surgical treatment of proximal humeral fractures.

Staged external and internal locked plating for open distal tibial fractures.

BACKGROUND AND PURPOSE: Based on reported success with staged treatment of distal tibial fractures, we designed a 2-stage protocol including external/internal locked plating. We retrospectively assessed the outcome of open distal tibial fractures treated according to this protocol. PATIENTS AND METHODS: From March 2006 through July 2008, 16 patients who sustained open distal tibial fractures were treated by a two-stage protocol. The first stage consisted of low-profile, locked plates for temporary external fixation after debridement and anatomic reduction, followed by soft tissue reconstruction. The second stage consisted of locked plates for definitive internal fixation, using minimally invasive percutaneous osteosynthesis. All fractures were followed for median 2 (1-3) years. RESULTS: The reduction was classified as being good in 15 patients and fair in 1 patient. All fractures united at a median of 6 (6-12) months. At the latest follow-up, 7 patients had excellent and 9 had good Iowa ankle scores; ankle motion ranged from a median of 10 (5-20) degrees of dorsiflexion to 40 (20-60) degrees of plantar flexion. INTERPRETATION: We believe that the 2-stage external/internal locked plating technique is an effective procedure for treatment of open distal tibial fractures in patients who need a long period of external fixation. We achieved good reduction with immediate ankle-sparing stable fixation. Soft tissue reconstruction and subsequent definitive fixation led to union of all fractures with good function.

Endovascular retrieval of a migrating pedicle screw within the inferior vena cava after instrumented spinal surgery: case report.

During L3-5 instrumented spinal surgery for degenerative spondylolisthesis in a 75-year-old woman, the right L-3 pedicle screw was accidentally pushed into the retroperitoneum and then migrated to the inferior vena cava (IVC). The patient was transferred to the surgical intensive care unit, and after careful discussion with cardiology specialists, a minimally invasive endovascular technique was used to remove the migrating pedicle screw within the IVC and thus salvage this critical case. Pedicle screw instrumentation is an effective procedure, but not risk free. Every detail should be scrutinized during surgery, even instrument construction. A minimally invasive endovascular technique should be considered in this patient population.

Assessment of thermal necrosis risk regions for different bone qualities as a function of drilling parameters.

BACKGROUND AND OBJECTIVE: During bone drilling, the heat generated by friction depends directly on bone quality and surgical parameters. Excessive bone temperatures may cause thermal necrosis around the pilot hole, weaken the purchase of inserted screws, and in turn reduce the stability of screw fixation. A few studies have addressed the key parameters of drilling, such as the rotation speed of the drill-bit, feed force (axial force), feed rate, tool type, and tip geometry of drill-bits. Nevertheless, in the literature, information on the relationship between bone quality and thermally affected regions is still lacking. This study employed a three-dimensional dynamic elastoplastic finite element model to evaluate the influence of surgical parameters on the bone temperature elevation and assess the risk region of thermal necrosis for different bone qualities as a function of drilling parameters. METHODS: To ascertain the heat generation rate and the high-risk region of thermal necrosis, the effects of bone quality, feed rate, feed force, and drill-bit diameter on the bone temperature elevation were explained using a three-dimensional dynamic elastoplastic finite element model, which was validated through experimental measurements. RESULTS: The bone temperature was affected by the drilling parameters; the maximum temperature was attained at the junction of cancellous and cortical bones. The bone temperature increased with cortical bone thickness, bone density, and drill-bit diameter, and it decreased with the drilling speed and feed force. CONCLUSIONS: The present model could assess the risk region of thermal necrosis by accurately analyzing the bone temperature elevation for various bone qualities, feed forces, and feed rates. The bone temperature increased with the bone mineral density and cortical bone thickness. The highest bone temperature and maximum necrosis region were found near the junction of cortical and cancellous bones. Increasing the drilling speed or feed force can minimize the bone temperature elevation and the risk range of thermal necrosis.

Role of vascularized bone grafts in lower extremity osteomyelitis.

Vascularized bone grafting seems to be a valuable reconstructive technique for the treatment of osteomyelitis with skeletal defects greater than 6 cm in length. Fibular osteocutaneous, composite rib, and iliac osteocutaneous flaps are the most commonly used vascularized bone grafts clinically. Vascularized bone can obliterate dead space, bridge large bone defects, enhance bone healing, resist infection by ensuring blood supply, allow early rehabilitation, and ensure better clinical outcomes in the treatment of lower extremity osteomyelitis. Success rates range from 80% to 95%. Complications of surgery include anastomosis failure, donor site problems, and fracture of the grafted bone.

Evaluation of the parameters affecting bone temperature during drilling using a three-dimensional dynamic elastoplastic finite element model.

A three-dimensional dynamic elastoplastic finite element model was constructed and experimentally validated and was used to investigate the parameters which influence bone temperature during drilling, including the drill speed, feeding force, drill bit diameter, and bone density. Results showed the proposed three-dimensional dynamic elastoplastic finite element model can effectively simulate the temperature elevation during bone drilling. The bone temperature rise decreased with an increase in feeding force and drill speed, however, increased with the diameter of drill bit or bone density. The temperature distribution is significantly affected by the drilling duration; a lower drilling speed reduced the exposure duration, decreases the region of the thermally affected zone. The constructed model could be applied for analyzing the influence parameters during bone drilling to reduce the risk of thermal necrosis. It may provide important information for the design of drill bits and surgical drilling powers.