Impact of instrumentation material on local recurrence: a case-matched series using carbon fiber-PEEK vs. titanium.

PURPOSE: Spine metastases are a major burden of oncologic care, contributing to substantial morbidity. A well-established treatment paradigm for patients with metastatic epidural spinal cord compression includes separation surgery followed by stereotactic body radiotherapy (SBRT). Innovations in implant technology have brought about the incorporation of Carbon fiber-reinforced polyetheretherketone (CFR-PEEK) instrumentation for spinal fixation. We present our experience of CFR-PEEK instrumentation, comparing outcomes and complication profiles with a matched cohort of titanium instrumented cases for spine metastatic disease. METHODS: Oncology patients who underwent spinal fusion for metastatic spine disease from 2012 to 2023 were retrospectively reviewed. Ninety-nine cases with CFR-PEEK fusions were case-control matched with 50 titanium controls (2:1 ratio) based upon primary tumor type and spinal instability neoplastic score (SINS) location. Demographic, clinical, radiographic and progression free survival (PFS) were analyzed. RESULTS: In the study years, 263 patients underwent spinal decompression and fusion, for which 148 patients met predetermined inclusion criteria. Of these, 49 had titanium instrumentation, and 99 had CFR-PEEK. Complication profiles, including hardware failure and infection were similar between the groups. There was no significant difference in PFS between all CFR-PEEK and titanium patients (143 days versus 214 days; p = 0.41). When comparing patients in which recurrence was noted, CFR-PEEK patients had recurrence detected two times earlier than titanium patients (94 days versus 189 days; p = 0.013). CONCLUSION: In this case matched cohort, CFR-PEEK demonstrated decreased overall PFS suggestive of earlier local recurrence identification. Long-term studies are warranted for better evaluation of the impact on survival and systemic disease progression.

Risk factors of instrumentation failure after laminectomy and posterior cervical fusions (PCF).

BACKGROUND: For patients with multilevel degenerative cervical myelopathy, laminectomy and posterior cervical fusions (PCF) with instrumentation are widely accepted techniques for symptom relief. However, hardware failure is not rare and results in neck pain or even permanent neurological lesions. There are no in-depth studies of hardware-related complications following laminectomy and PCF with instrumentation. METHODS: The present study was a retrospective, single centre, observational study. Patients who underwent laminectomy and PCF with instrumentation in a single institution between January 2019 and January 2021 were included. Patients were divided into hardware failure and no hardware failure group according to whether there was a hardware failure. Data, including sex, age, screw density, end vertebra (C7 or T1), cervical sagittal alignment parameters (C2-C7 cervical lordosis, C2-C7 sagittal vertical axis, T1 slope, Cervical lordosis correction), regional Hounsfield units (HU) of the screw trajectory and osteoporosis status, were collected and compared between the two groups. RESULTS: We analysed the clinical data of 56 patients in total. The mean overall follow-up duration was 20.6 months (range, 12-30 months). Patients were divided into the hardware failure group (n = 14) and no hardware failure group (n = 42). There were no significant differences in the general information (age, sex, follow-up period) of patients between the two groups. The differences in fusion rate, fixation levels, and screw density between the two groups were not statistically significant (p > 0.05). The failure rate of fixation ending at T1 was lower than that at C7 (9% vs. 36.3%) (p = 0.019). The regional HU values of the pedicle screw (PS) and lateral mass screw (LMS) in the failure group were lower than those in the no failure group (PS: 267 ± 45 vs. 368 ± 43, p = 0.001; LMS: 308 ± 53 vs. 412 ± 41, p = 0.001). The sagittal alignment parameters did not show significant differences between the two groups before surgery or at the final follow-up (p > 0.05). The hardware failure rate in patients without osteoporosis was lower than that in patients with osteoporosis (14.3% vs. 57.1%) (p = 0.001). CONCLUSIONS: Osteoporosis, fixation ending at C7, and low regional HU value of the screw trajectory were the independent risk factors of hardware failure after laminectomy and PCF. Future studies should illuminate if preventive measures targeting these factors can help reduce hardware failure and identified more risk factors, and perform long-term follow-up.

Complications of Anterior Cervical Discectomy and Fusion.

Anterior cervical discectomy and fusion (ACDF) is the most common surgery performed on the cervical spine, and the number of its cases has tripled over the last two decades. Although this intervention is typically safe and effective, it carries an inherent complication risk, which should not be underestimated. Improvements in surgical techniques and advances in interbody fusion devices and plating systems have certainly reduced the rate of postoperative morbidity, but despite such progress, surgeons need to beware consistently of the potential complications, inform the patient of their possibility, and have a management strategy as they develop. This review discusses postoperative morbidity encountered in recently reported large studies on ACDF and highlights the senior author's own single-surgeon experience with 2579 such procedures performed between 1998 and 2017. In his clinical series, which is the largest one reported to date, the overall complication rate was 7.0% (180 cases), and dysphagia (1.9% of cases), graft/hardware failures (1.3% of cases), and postoperative hematomas (0.9% of cases) were noted most frequently. Understanding of the risk and clinical impact of complications after ACDF is very important and every effort should be put on their possible avoidance and on appropriate management when they do occur.

Complications of deep brain stimulation in Parkinson's disease: a single-center experience of 517 consecutive cases.

BACKGROUND: The number of deep brain stimulation (DBS) procedures is rapidly rising as well as the novel indications. Reporting adverse events related to surgery and to the hardware used is essential to define the risk-to-benefit ratio and develop novel strategies to improve it. OBJECTIVE: To analyze DBS complications (both procedure-related and hardware-related) and further assess potential predictive factors. METHODS: Five hundred seventeen cases of DBS for Parkinson's disease were performed between 2006 and 2021 in a single center (mean follow-up: 4.68 ± 2.86 years). Spearman's Rho coefficient was calculated to search for a correlation between the occurrence of intracerebral hemorrhage (ICH) and the number of recording tracks. Multiple logistic regression analyzed the probability of developing seizures and ICH given potential risk factors. Kaplan-Meier curves were performed to analyze the cumulative proportions of hardware-related complications. RESULTS: Mortality rate was 0.2%, while permanent morbidity 0.6%. 2.5% of cases suffered from ICH which were not influenced by the number of tracks used for recordings. 3.3% reported seizures that were significantly affected by perielectrode brain edema and age. The rate of perielectrode brain edema was significantly higher for Medtronic's leads compared to Boston Scientific's (Χ2(1)= 5.927, P= 0.015). 12.2% of implants reported Hardware-related complications, the most common of which were wound revisions (7.2%). Internal pulse generator models with smaller profiles displayed more favorable hardware-related complication survival curves compared to larger designs (X2(1)= 8.139, P= 0.004). CONCLUSION: Overall DBS has to be considered a safe procedure, but future research is needed to decrease the rate of hardware-related complications which may be related to both the surgical technique and to the specific hardware's design. The increased incidence of perielectrode brain edema associated with certain lead models may likewise deserve future investigation.

Results of pre-contoured titanium anterior plating of midshaft clavicle fractures.

BACKGROUND: Plating midshaft clavicle fractures anteriorly is gaining popularity because of low complication rates. Improvements in plate fixation constructs for midshaft clavicle fractures have unclear clinical significance. The purpose of this study was to present the early clinical and radiographic outcomes of pre-contoured titanium anterior plates for the treatment of midshaft clavicle fractures. METHODS: Skeletally mature patients who underwent plate fixation of a midshaft clavicular fracture from 2008 to 2015 using pre-contoured titanium anterior plates were included in this retrospective investigation. The primary outcome measures were union rate and hardware removal rate. The secondary outcome measures included reoperation for all causes and mechanical implant failure. RESULTS: A total of 26 patients were included. Complete healing occurred in 96% of patients without further surgical intervention, and all patients achieved union. Medical complications occurred in 2 patients (7.7%), consisting of cellulitis (n = 1) and chronic pain (n = 1). In 1 patient (3.8%), delayed union occurred and the use of a bone stimulator was required postoperatively to achieve union. Finally, 2 patients (7.7%) had symptomatic implants that required removal. CONCLUSIONS: In the acute fracture setting, the anterior plating system used in this study led to a high rate of union with decreased rates of implant irritation. Only 7.7% of patients required hardware removal for symptomatic hardware, as opposed to the estimated 20%-60% reported in the literature in patients with symptomatic superior clavicle plates.

Surgical and Hardware-Related Adverse Events of Deep Brain Stimulation: A Ten-Year Single-Center Experience.

INTRODUCTION: Although deep brain stimulation (DBS) is effective for treating a number of neurological and psychiatric indications, surgical and hardware-related adverse events (AEs) can occur that affect quality of life. This study aimed to give an overview of the nature and frequency of those AEs in our center and to describe the way they were managed. Furthermore, an attempt was made at identifying possible risk factors for AEs to inform possible future preventive measures. MATERIALS AND METHODS: Patients undergoing DBS-related procedures between January 2011 and July 2020 were retrospectively analyzed to inventory AEs. The mean follow-up time was 43 ± 31 months. Univariate logistic regression analysis was used to assess the predictive value of selected demographic and clinical variables. RESULTS: From January 2011 to July 2020, 508 DBS-related procedures were performed including 201 implantations of brain electrodes in 200 patients and 307 implantable pulse generator (IPG) replacements in 142 patients. Surgical or hardware-related AEs following initial implantation affected 40 of 200 patients (20%) and resolved without permanent sequelae in all instances. The most frequent AEs were surgical site infections (SSIs) (9.95%, 20/201) and wire tethering (2.49%, 5/201), followed by hardware failure (1.99%, 4/201), skin erosion (1.0%, 2/201), pain (0.5%, 1/201), lead migration (0.52%, 2/386 electrode sites), and hematoma (0.52%, 2/386 electrode sites). The overall rate of AEs for IPG replacement was 5.6% (17/305). No surgical, ie, staged or nonstaged, electrode fixation, or patient-related risk factors were identified for SSI or wire tethering. CONCLUSIONS: Major AEs including intracranial surgery-related AEs or AEs requiring surgical removal or revision of hardware are rare. In particular, aggressive treatment is required in SSIs involving multiple sites or when Staphylococcus aureus is identified. For future benchmarking, the development of a uniform reporting system for surgical and hardware-related AEs in DBS surgery would be useful.

Systematic Review and Meta-Analysis of Hardware Failure in Surgical Stabilization of Rib Fractures: Who, What, When, Where, and Why?

BACKGROUND: Surgical stabilization of rib fractures (SSRF) is increasingly used to reduce pulmonary complications and death among patients with rib fractures. However, the five Ws of hardware failure -who, what, when, where, and why- remains unclear. We aimed to synthesize available evidence on the five Ws and outline future research agenda for mitigating hardware failure. METHODS: Experimental and observational studies published between 2009 and 2020 evaluating adults undergoing SSRF for traumatic rib fractures underwent evidence synthesis. We performed random effects meta-analysis of cohort/consecutive case studies. We calculated pooled prevalence of SSRF hardware failures using Freeman-Tukey double arcsine transformation and assessed study heterogeneity using DerSimonian-Laird estimation. We performed meta-regression with rib fracture acuity (acute or chronic) and hardware type (metal plate or not metal plate) as moderators. RESULTS: Twenty-nine studies underwent qualitative synthesis and 24 studies (2404 SSRF patients) underwent quantitative synthesis. Pooled prevalence of hardware failure was 4(3-7)%. Meta-regression showed fracture acuity was a significant moderator (P = 0.002) of hardware failure but hardware type was not (P = 0.23). Approximately 60% of patients underwent hardware removal after hardware failure. Mechanical failures were the most common type of hardware failure, followed by hardware infections, pain/discomfort, and non-union. Timing of hardware failure after surgery was highly variable, but 87% of failures occurred after initial hospitalization. Mechanical failures was attributed to technical shortcomings (i.e. short plate length) or excessive force on the thoracic cavity. CONCLUSIONS: SSRF hardware failure is an uncommon complication. Not all hardware failures are consequential, but insufficient individual patient data precluded characterizing where and why hardware failures occur. Minimizing SSRF hardware failure requires concerted research agenda to expand on the paucity of existing evidence.

High lead impedances requiring revision during vagal nerve stimulator generator replacement.

OBJECTIVE: Vagal nerve stimulation (VNS) therapy is among the growing options in the treatment of intractable epilepsy. The phenomenon of surprise lead impedance issues found at the time of surgery resulting in unplanned lead revision is a challenge with this type of device. We reviewed our experience with VNS revisions. MATERIAL AND METHODS: We retrospectively reviewed the records of all adult and pediatric patients between January 2009 and September 2018 who underwent surgery for VNS therapy, including revision surgery. Office and operative notes were reviewed to obtain the indications and operative details for VNS placement. RESULTS: A total of 570 operations were reviewed. The indication was intractable epilepsy in all cases. Primary implantation was performed in 232 patients, while the remaining 338 cases were revision cases of various natures. Surprise high lead impedance was found in 10 (3%) of these cases, resulting in a significantly increased complexity of surgery in those instances. CONCLUSION: Lead impedance issues can be caused by disconnection, electrode fracture, hardware failure, or tissue scarring but ultimately require a more extended surgery than may be initially planned. Anticipating the potential for a more extensive operation than a simple generator replacement may prevent perioperative frustrations on both sides.

Short-term complications of the Latarjet procedure: a systematic review.

PURPOSE: The purpose of this study is to evaluate the short-term complication rate following the open and arthroscopic Latarjet procedures and to meta-analyze the studies comparing the 2 approaches. METHODS: PubMed was searched according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines to find clinical and biomechanical studies comparing complication rates in open and arthroscopic Latarjet procedures. A literature search of MEDLINE, Embase, and the Cochrane Library was performed based on the PRISMA guidelines. Clinical studies reporting on the complications following the open or arthroscopic Latarjet were included. Meta-analysis was performed for comparative studies using Review Manager, version 5.3. A P value of <.05 was considered statistically significant. RESULTS: Overall, 89 studies (Level of Evidence [LOE] I: 2, LOE II: 2, LOE III: 24, LOE IV: 61) met inclusion criteria, with 7175 shoulders. Following the open Latarjet procedure, the overall complication rate was 6.1%, with a 1.9% occurrence of graft-related complications, 1.1% hardware, 1.1% wound, 0.9% nerve, and 1.2% other complications. Following the arthroscopic Latarjet procedure, the overall complication rate was 6.8%, with a 3.2% occurrence of graft-related complications, 1.9% hardware, 0.5% wound, 0.7% nerve, and 0.5% other complications. Complications were reported in 7 studies comparing 379 patients treated with the open Latarjet and 531 treated with the arthroscopic Latarjet, with no statistically significant difference between the two (P = .81). CONCLUSION: Our study established that the overall complication rate following the Latarjet procedure was 6%-7%, with the most common complication being graft-related. Furthermore, based on the current evidence, there is no significant difference in the complication rate between the open and arthroscopic Latarjet procedures.

Hardware Failure Prediction on Imbalanced Times Series Data : Generation of Artificial Data Using Gaussian Process and Applying LSTMFCN to Predict Broken Hardware.

Magnetic resonance imaging (MRI) systems and their continuous, failure-free operation is crucial for high-quality diagnostics and seamless workflows. One important hardware component is coils as they detect the magnetic signal. Before every MRI scan, several image features are captured which represent the used coil's condition. These image features recorded over time are used to train machine learning models for classification of coils into normal and broken coils for faster and easier maintenance. The state-of-the-art techniques for classification of time series involve different kinds of neural networks. We leveraged sequential data and trained three models, long short-term memory (LSTM), fully convolutional network (FCN), and the combination of those called LSTMFCN as reported by Karim et al. (IEEE access 6:1662-1669, 2017). We found LSTMFCN to combine the benefits of LSTM and FCN. Thus, we achieved the highest F1-score of 87.45% and the highest accuracy of 99.35% using LSTMFCN. Furthermore, we tackled the high data imbalance of only 2.1% data collected from broken coils by training a Gaussian process (GP) regressor and adding predicted sequences as artificial samples to our broken labelled data. Adding 40 synthetic samples increased the classification results of LSTMFCN to an F1-score of 92.30% and accuracy of 99.83%. Thus, MRI head/neck coils can be classified normal or broken by training a LSTMFCN on image features, successfully. Augmenting the data using GP-generated samples can improve the performance even further.

Allergy Considerations in Implanted Neuromodulation Devices.

OBJECTIVES: Allergic reactions are rare and poorly understood complications of neuromodulation device implantation. There are currently no guidelines for management of allergic reactions to these devices and their components. Here we review the published cases of allergic reactions to implanted neuromodulatory devices and leverage the experiences of other specialties that deal with similar complications to formulate recommendations for prevention and management. MATERIALS AND METHODS: A review and assessment of the literature. RESULTS: Allergic reactions to a number of implantable devices have been observed and published. In dentistry and orthopedics, metals such as nickel are the most frequent cause of allergic reactions. In interventional cardiology, where devices closely resemble neuromodulatory devices, titanium, silicone, and polyurethanes are the most common causes of allergic reactions. In neurosurgery, allergic reactions to implantable neuromodulatory devices are rare, and we summarize 13 cases published to date. Such allergic reactions generally present as local dermatitis, erythema, and pruritus, which can be difficult to distinguish from surgical site infection. In one published case, symptoms resolved with corticosteroid treatment, but all other cases required explantation. The successful reimplantation with a modified device was reported in some cases. CONCLUSIONS: Patients should be screened for a personal history of contact allergy before implantation procedures. A multidisciplinary approach to suspected cases of postoperative allergic reactions involving collaboration between neurosurgeons and other implanting physicians, dermatologists or allergists, and device manufacturers is recommended. In cases where an allergic reaction is suspected, an infectious etiology should be ruled out first. Clinical suspicion can then be supported with the use of patch testing, interpreted by an experienced dermatologist or allergist. If patch testing supports an allergic etiology, the implanting physician and the device manufacturer can work together to modify the device for safe reimplantation.

En bloc resection in patients younger than 16 years affected by primary spine tumors: indications, results and complications in a series of 22 patients.

PURPOSE: Review a series of 22 patients below the age of 16 affected by primary bone tumors of the spine who underwent en bloc resection, and describe the clinical presentation, tumor characteristics, results and complications associated with the surgical treatment, underlining the specific issues related to a younger age. METHODS: We performed a review of all patients < 16 years old affected by primary bone tumors of the spine, surgically treated with en bloc resection from 1996 to 2016. Clinical and radiological characteristics, therapy, complications and survival are reported. RESULTS: Only 12/22 cases had not been previously treated. 22.7% experienced at least one early complication; 18.2% and 4.1% experienced at least 2 and ≥ 3 early complications, respectively; 40.9% experienced at least one late complication, often related to hardware failure (27.3%); 18.2% and 4.5% at least 2 and ≥ 3 late complications. No early nor late complications were experienced in 12 out of 22 patients (54.54%). The overall survival and the local recurrence-free survival at 5 years were, respectively, 79.5% and 74.8%; considering only the patients with high-grade tumors, they were 70.9% and 65.5%, respectively. At 77.3 months of median follow-up, 17 patients are still alive, 16 of whom without any evidence of disease and 1 with evidence of local and systemic disease; four patients died with evidence of local disease and one with distant metastases but no local recurrence. CONCLUSIONS: Young people with primary malignant or locally aggressive bone tumors of the spine should be treated in specialized centers, and wide surgery should be performed. The most frequent problems are related to reconstruction in a growing spine and subsequent hardware failure that make later surgeries necessary. These slides can be retrieved under Electronic Supplementary Material.

Complications after operatively treated distal radius fractures.

In the recent years, treatment of distal radius fractures (DRF) has advanced considerably. Surgical fixation with palmar angular stable plate has gained popularity, due to a reported lower complication rate when compared to dorsal fixation. The type of trauma or injury, surgical procedure and impaired bone quality are all contributors to complications in DRF. The main aim of this review is to summarize the most common complications and possible therapeutic solutions. In addition, strategies for minimizing these complications will be discussed.

Prognostic risk factors for complications associated with tibiotalocalcaneal arthrodesis with a nail.

BACKGROUND: Tibiotalocalcaneal (TTC) arthrodesis with a nail can be an effective salvage procedure for several foot and ankle pathologies, but has a relatively high complication rate. The purpose of this study is to investigate risk factors associated with complications after TTC arthrodesis with a nail. METHODS: Clinical and radiographic outcomes for 82 patients from 2012 to 2016 who underwent TTC arthrodesis with a nail were retrospectivelyevaluated to determine if patient or surgeon specific variables offered prognostic value in predicting negative outcomes. RESULTS: Diabetes, diabetic neuropathy, high (>2) American Society of Anesthesiologists (ASA) classification, and Charcot neuroarthropathy all were predictive of developing a nonunion in either the subtalar ortibiotalar joints (p<0.05). Diabetic neuropathy was predictive ofreoperation, and along with HbA1C >7.5 was also predictive of hardwarefailure. The odds ratio (OR) for diabetic neuropathy was 2.99 (p<0.05)for nonunion in the tibiotalar or subtalar joints, 3.46 (p<0.05) for reoperation,and 4.11 (p<0.05) for hardware failure. High ASAclassification had an odds ratio of 3.93 (p<0.05) for nonunion in the tibiotalar or subtalar joints as well. Diabetes had an odds ratio of 2.57 (p<0.05) for nonunion. CONCLUSIONS: Patients with diabetic neuropathy, Charcot neuroarthropathy, elevated HbA1C, and ASA classification >2 demonstrated a higher complication rate in patients undergoing TTC arthrodesis with a nail.

Case report: migration of a broken screw to the knee joint after hardware failure following closing wedge distal femoral osteotomy.

BACKGROUND: We report a case of hardware failure after distal femoral osteotomy (DFO) with a broken screw pulled out from the locking hole and positioned within the knee joint. CASE PRESENTATION: A 57-year-old man presented to our orthopedic outpatient department with 3-months history of an unusual painful swelling at the operated area following DFO. The leakage of joint fluid from the penetrated suprapatellar pouch was assumed to be the reason for this complication. CONCLUSIONS: The overall aim of this case report is to provide a lesson to budding surgeons who might experience a similar situation that cannot be easily explained, like the unexpected complication in the present case.

Is Routine Hardware Removal Following Open Reduction Internal Fixation of Tarsometatarsal Joint Fracture/Dislocation Necessary?

Open reduction internal fixation (ORIF) is an accepted treatment for displaced tarsometatarsal joint (TMTJ) fracture dislocations. In general, hardware is routinely removed after 4 months to allow restoration of joint motion and avoid complications of hardware failure. Because few studies report outcomes of TMTJ fractures with retained hardware, there is little consensus regarding the optimal time for hardware removal or if hardware retention leads to adverse outcomes. We retrospectively reviewed the radiographic outcomes of retained hardware after ORIF of TMTJ fractures/dislocations in 61 patients. The mean age at the time of operation was 37.3 ± 14.9 years. ORIF was performed with 3.5 fully threaded cortical screws. Assessment of clinical and radiographic results was performed at 2 weeks, 6 weeks, 3 months, 6 months, and 12 months after surgical treatment. Out of the 61 patients that were included in this study, only 2 demographic variables demonstrated a trend for an adverse outcome. Older age correlated with lost reduction and elevated body mass index correlated with hardware failure. The presence of diabetes was correlated with an increased risk of postoperative infection but not hardware failure. During our follow-up period there were 49 patients (80.3 %) without failure of fixation. In conclusion, our study suggests that routine removal of hardware following open reduction and internal fixation of Lisfranc injuries in patients may not be necessary.

"Revision of subtrochanteric femoral nonunions after intramedullary nailing with dynamic condylar screw".

BACKGROUND: Nonunions of the subtrochanteric region of the femur after previous intramedullary nailing can be difficult to address. Implant failure and bone defects around the implant significantly complicate the therapy, and complex surgical procedures with implant removal, extensive debridement of the nonunion site, bone grafting and reosteosynthesis usually become necessary. The purpose of this study was to evaluate the records of a series of patients with subtrochanteric femoral nonunions who were treated with dynamic condylar screws (DCS) regarding their healing rate, subsequent revision surgeries and implant-related complications. METHODS: We conducted a retrospective chart review of patients with aseptic femoral subtrochanteric nonunions after failed intramedullary nailing. Nonunion treatment consisted of nail removal, debridement of the nonunion, and restoration of the neck shaft angle (CCD), followed by DCS plating. Supplemental bone grafting was performed in all atrophic nonunions. All patients were followed for at least six months after DCS plating. RESULTS: Between 2002 and 2017, we identified 40 patients with a mean age of 65.4 years (range 34-91 years) who met the inclusion criteria. At a mean follow-up period of 26.3 months (range 6-173), 37 of the 40 (92.5%) nonunions healed successfully (secondary procedures included). The mean healing time of the 37 patients was 11.63 months (± 12.4 months). A total of 13 of the 40 (32.5%) patients needed a secondary revision surgery; one patient had a persistent nonunion, nine patients had persistent nonunions leading to hardware failure, two patients had deep infections requiring revision surgery, and one patient had a peri-implant fracture due to low-energy trauma four days after the index surgery. CONCLUSIONS: The results indicate that revision surgery of subtrochanteric femoral nonunions after intramedullary nailing with dynamic condylar screws is a reliable treatment option overall. However, secondary revision surgery may be indicated before final healing of the nonunion.

Bone SPECT/CT in the postoperative spine: a focus on spinal fusion.

Low back pain is a global problem affecting one in 10 people. The management of low back pain varies from conservative to more invasive methods with a spectacular increase in the number of patients undergoing spinal fusion surgery during the last decade. Conventional radiological and radionuclide studies are often used in the assessment of persistent or recurring pain after spinal surgery with several advantages and limitations related to each technique. This article reviews the key contribution of integrated bone SPECT/CT in evaluating patients with persistent or recurring pain after spinal surgery, focusing on spinal fusion. Current literature supports the use of bone SPECT/CT as an adjunct imaging modality and problem-solving tool in evaluating patients with suspicion of pseudarthrosis, adjacent segment degeneration, and hardware failure. The role of bone SPECT/CT in post-operative orthopaedic scenarios is evolving, and this review highlights the need for further research on the role of bone SPECT/CT in these patients.

Proximal ingrowth coating decreases risk of loosening following uncemented shoulder arthroplasty using mini-stem humeral components and lesser tuberosity osteotomy.

BACKGROUND: Mini-stem humeral component (MSHC) use during total shoulder arthroplasty (TSA) provides bone preservation and ease of revision. MSHCs rely solely on proximal metaphyseal fixation; some early reports have demonstrated an unacceptably high rate of early loosening. To our knowledge, no study analyzing the effect of proximal porous coating on MSHCs has been performed. METHODS: We performed a retrospective review of consecutive patients who underwent anatomic TSA using coated or uncoated MSHCs with minimum 2-year follow-up. Postoperative radiographs were assessed for risk of or frank stem loosening, subsidence, and presence of radiolucencies. Range of motion, outcome scores (visual analog scale pain, American Shoulder and Elbow Surgeons, and Single Assessment Numeric Evaluation), and any complications were noted. RESULTS: We analyzed 68 shoulders with a mean follow-up of 27.3 months (range, 24-50 months). Of these, 34 had proximal coating and 34 were uncoated. In the coated group, no stems loosened, 1 (2.9%) subsided, and 7 (20.6%) developed radiolucencies. In the uncoated group, 1 stem (2.9%) became aseptically loose (requiring revision after 26 months), 7 (20.6%) were judged at risk of loosening (2 because of subsidence), and 15 (44.1%) developed radiolucencies. There was also an increased risk of proximal medial humeral radiolucencies among uncoated MSHCs. There were no significant differences in final range of motion or outcome scores. CONCLUSION: MSHC use is appropriate for TSA, achieving desired pain relief and functional improvement. Overall, component loosening appears uncommon at early follow-up; however, uncoated stems appear to be at greater risk of loosening and developing radiolucencies. Selecting an MSHC with proximal porous coating may decrease the risk of implant-related complications.

Dual Anchor Internal Pulse Generator Technique May Lower Risk of Twiddler's Syndrome: A Case Series and Literature Review.

BACKGROUND: Twiddler's syndrome (TS) is described as a spontaneous rotation or intentional external manipulation of implanted internal pulse generator (IPG) for neurological or cardiac disorders. There have been identified some predisposing factors of the development of TS such as: loose subcutaneous tissue, older age of individuals undergoing deep brain stimulation (DBS) procedures, creation of too large pockets for IPG. Apart from these factors, the construction of IPG itself may predispose to the development of TS. OBJECTIVE: To report the clinical course of three patients with TS. Moreover, the purpose of this study is to present the change in fixation technique of IPG that can prevent the occurrence of TS in patients after DBS procedure. METHODS: A prospectively collected database of all hardware related complications for patients operated on for various movement disorders was analyzed. In a total number of 347 DBS systems implanted since 1999 we have identified three patients diagnosed with TS. All three patients with TS in our series were implanted with the IPG harboring a single anchoring hole. This complication has never occurred in patients with the IPG harboring two anchoring holes in our center. RESULTS: All three patients underwent revision surgery. During reoperations all connection cables were replaced and IPG sutured with one additional silk stich through the plastic housing to immobilize it properly in subcutaneous pocket. There were no recurrences of TS in our patients. CONCLUSIONS: Our case series suggests that a predisposing factor of TS may also be the construction of IPG itself (a single anchoring hole intended for fixation), which naturally represents less fixation of the IPG to the fascia or muscle in the subcutaneous pocket. In this preliminary report we present suggestions to lower the risk of TS, including using dual anchor capable IPGs, reducing pocket volume and using nonabsorbable suture.