Nonunion Of Fusion Research Articles

Fractured vertebra antedisplacement reconstruction technique: a feasible treatment choice for posttraumatic thoracolumbar kyphosis.

The goal of this study was to evaluate the feasibility of the fractured vertebra antedisplacement reconstruction technique for the treatment of posttraumatic thoracolumbar kyphosis (PTK). A total of 22 patients with PTK who were treated with the fractured vertebra antedisplacement reconstruction technique were retrospectively analyzed. The radiological evaluation included global kyphosis, thoracolumbar angle, and sagittal vertical axis. The clinical evaluation included visual analog scale pain score, Oswestry Disability Index score, SF-12 Health Survey score, and American Spinal Injury Association grade. The complications were recorded. The mean global kyphosis was 55.0° ± 12.6° preoperatively, 8.5° ± 5.0° postoperatively, and 10.3° ± 4.8° at the latest follow-up (p < 0.001). The average total kyphosis correction achieved was 44.7° ± 14.2°, with a range of 23.4°-79.4°, indicating a mean final correction of 80.1%. The mean thoracolumbar angle was 46.2° ± 13.2° preoperatively, 6.6° ± 4.5° postoperatively, and 7.6° ± 4.2° at the latest follow-up (p < 0.001). The mean sagittal vertical axis was improved significantly, from 51.1 ± 24.2 mm preoperatively to 28.5 ± 17.4 mm at the latest follow-up (p = 0.001). One patient (4.5%) experienced single intervertebral fusion nonunion, and 1 patient (4.5%) experienced distal screw loosening. No patients experienced any neurological deterioration. The visual analog scale pain score, Oswestry Disability Index score, SF-12 Health Survey score, and American Spinal Injury Association grade achieved significant improvement at the latest follow-up. Fractured vertebra antedisplacement reconstruction technique can effectively correct kyphosis, reconstruct spinal stability, and improve the patient's symptoms and neurological function. This technique is safer, minimally traumatic, and less technically demanding to avoid osteotomy-related complications. It is a feasible treatment choice for PTK.

Navigated Simultaneous Lateral Minimally Invasive Tubular and Posterior Mini-Open Access for Removal and Revision of Triangular Sacroiliac Joint Implants: A Technical Note

Sacroiliac joint (SIJ) fusion, to treat back pain caused by SIJ dysfunction, can employ open or minimally invasive surgery (MIS) techniques and either cylindrical (screw-shaped) or triangular (wedge-shaped) implants. Fusion nonunion sometimes explains recurrent SIJ pain following fusion and occasionally requires hardware revision. MIS revision minimizes patient pain, infection, and disability, but due to the triangular implant size and form factor, implant removal can present challenges for MIS access during the explantation and achieving good bony purchase for reinstrumentation. Here, we report a prone single-position lateral MIS/posterior mini-open procedure for triangular-implant SIJ fusion revision. The patient is a 72-year-old female who underwent right SIJ fusion for lower back and leg pain sustained after a fall 2 years prior but experienced recurrent pain over the subsequent 2 years, with imaging findings of right SIJ peri-hardware lucencies and diagnostic injections confirming persistent right-sided sacroiliitis. The patient underwent hardware removal using the lateral MIS incision with table-mounted tubular access and image-guided navigation to maintain exposure, plus simultaneous reinstrumentation using a navigated S2-alar-iliac screw and iliac bolt construct with connecting rod through the posterior mini-open incision made for the navigation reference frame spinous process clamp. The use of navigation and MIS access can significantly decrease the complexity of lateral hardware removal, and mini-open navigated screw-and-rod constructs offer reinstrumentation options accessible to surgeons unfamiliar with specialized posterior SIJ systems.

Patient Reported Outcomes Following Revision Ankle Arthrodesis for Ankle Fusion Non-Union

Category: Ankle Arthritis; Hindfoot Introduction/Purpose: Ankle arthrodesis (AA) has, for many years, been considered the gold standard procedure for the surgical treatment of end stage ankle arthritis. Non-union following AA surgery is a devastating complication which subsequently requires revision surgery. However, data on outcomes including patient reported outcome measures (PROMs) following revision ankle arthrodesis (RAA) after failed AA is lacking. The aim of this study is to assess the outcome of RAA for symptomatic non-union after AA including PROMs. Methods: Prospectively collected data from a multicenter database of ankle arthritis surgery was analyzed. Demographic data and PROMs including Ankle Osteoarthritis Scale (AOS) and Short Form-36 (SF-36) health survey were collected at regular intervals. Surgeries were performed by six fellowship-trained foot and ankle surgeons between January 2003 and July 2015. 336 primary AA cases were identified, of which 27 (8%) underwent revision for symptomatic AA non-union. Results: Mean follow-up of 27 AA non-union cases was 5.3 years (2-10). There were 16 (59%) males and 11 (41%) females, with a mean age of 62 years (44 - 81) and a mean BMI of 32 (26.5 – 45), respectively. At index AA, 12 (44%) cases were performed arthroscopically. Twenty-three (84%) AA non-union patients were actively smoking pre- and post-operatively, and 15 (56%) were diabetic. Overall union-rate following RAA was 85% (23/27). For RAA the pre-operative mean AOS score of 64.9 (38.8-81.5) improved to 49.1 (24.1-73) at latest follow-up. SF-36 PCS score improved from 27.2 (21.3 – 38.3) to 33.3 (19.1-54.2) and SF-36 MCS score improved from 41.2 (17.5-60.9) to 46.2 (29.3-65.9). Overall complication rate of RAA was 22%, with a re-operation rate of 15%. Conclusion: Revision ankle arthrodesis (RAA) for ankle fusion non-union resulted in a successful fusion of the ankle in 85% of patients with modest improvement in AOS and SF-36 scores. Indeed, even after successful RAA, patients report pain and disability levels comparable to that reported by primary AA patients pre-operatively. Additionally, complication and re-operation rates of RAA are high. This data emphasizes on the importance of achieving a primary fusion in AA. The presented patient reported outcomes may help the treating surgeon to counsel patients prior to RAA surgery to better set their expectations.

Conversion of Symptomatic Ankle Arthrodesis Nonunion to Total Ankle Arthroplasty Using Patient-specific Instrumentation and Computer-assisted Surgery Guides: A Case Report

A 69-year-old woman developed a painful ankle fusion nonunion and underwent conversion to a total ankle replacement. Preoperative navigation was performed using a computed tomography scan and computer modeling system to develop patient-specific instrumentation and surgery guides. We described the navigation process of a fixed-bearing, computer-guided total ankle implant when performing an ankle arthrodesis takedown due to symptomatic nonunion and converting to a total ankle arthroplasty. The use of this technology is relatively new, and, in this case, preoperative navigation allowed for precise implant planning while accounting for the osseous deformities from previous implants, which already fixated the ankle joint. Level of Evidence: Level IV.

90-Day Reoperation and Wound Complication Rates in Lateral Approach to Total Ankle Replacement for Post-Traumatic Arthritis

Category: Ankle Arthritis; Ankle; Diabetes Introduction/Purpose: Total ankle replacement (TAR) has achieved relatively successful outcomes with respect to postoperative complications; however, mixed evidence exists regarding early complication rates, reoperation, and infection1-5. The largest study of TAR to date indicates a statistically significant risk of postoperative infection in tobacco users and diabetic patients6. Unlike currently established anterior approaches to arthroplasty, the lateral transfibular approach potentially avoids disruption of perfusion to the skin, possibly decreasing postoperative complications7. The lateral ankle allows surgeons to correct malunion of the fibula in post-traumatic arthritis deformity cases and achieve appropriate coronal and sagittal implant alignment to achieve similar physiological joint orientation8,9. The purpose of this study was to report 90-day reoperation and wound complication rates in lateral approach to total ankle replacement for post-traumatic arthritis (PTA). Methods: A retrospective chart review of lateral TAR cases from 2016-2022 was conducted at a single institution. Only patients undergoing TAR for post-traumatic arthritis were included in this review. A total of 49 patients (22 females and 27 males) underwent total ankle replacement with the Zimmer Biomet Trabecular MetalTM Total Ankle by a single surgeon. Patient demographics, operative data, complications, and adverse events requiring corrective surgery were recorded within 90 days of arthroplasty. Results: The patient sample included 6 active smokers, 11 diabetics, and 32 patients with hypertension with an average age of 60.7 and average BMI of 34.3 (Table 1). Three of the 49 (6.1%) patients required secondary surgery within 3 months of surgery (Table 2). Revision surgery indications included: 1 (2.0%) for removing painful hardware, 2 (4.1%) due to infection, and 1 (2.0%) for tarsal tunnel syndrome after surgery. There were 0 nonunions of the fibula at 90 days and through 1 year follow up. Of the patients requiring secondary surgery for infection, 1 was a smoker and 1 had a history of ankle fusion nonunion and avascular necrosis which was converted to a TAR (Table 4). Conclusion: This retrospective study demonstrates a comparable rate of secondary surgeries following TAR via lateral approach in the early postoperative period (6.1%) while having a slightly higher rate of infection than those previously reported (4.1%)7,8. Notwithstanding, we observed a 100% healing rate of fibula osteotomies; however, we failed to demonstrate a lower incidence of wound complications than previously reported. Surgeons should counsel patients of these risks in those with PTA undergoing lateral TAR, especially in smokers and diabetics.

Experience of an isolated use of low-intensity pulsed ultrasound therapy on fracture healing in established non-unions: a prospective case series.

Fracture non-unions are responsible for approximately 5% of cases, with low expectation of spontaneous healing thereafter. The fractures that heal without complications can take months to heal completely. An ultrasound, typically at low intensities (0.5-50 mW/cm2), serves a diagnostic purpose, whereas at higher intensities (0.2-100W/cm2), its role becomes more therapeutic by generating heat energy. Low-intensity pulsed ultrasound (LIPUS) is frequently used to stimulate or to accelerate fracture healing. We present a prospective review of fracture non-unions treated with low-intensity pulsed ultrasound (LIPUS). We enrolled 66 patients during August 2016 and December 2018, 38 males and 28 females; age range 19-85years (average 49.2years). All these patients were followed up to minimum 6months. The average time of referral post-treatment for fractures was 8.2months (range 6-18months). Four patients were excluded due to various reasons. 39 out of 62 fractures showed successful healing with symptom improvement and callus formation with 67% success rate. In this case series, we noted LIPUS therapy failure in the post-ORIF scaphoid fracture and post-ankle joint fusion non-union. We did not observe any influence of a medical condition such as diabetes mellitus, osteoporosis or personal habits like smoking. The LIPUS therapy appears to have influence on bone healing, depending on the onset of therapy, fracture type and the approach to fracture care. In this case series, the compliant group showed 67% successful outcome.

Agonizing and Expensive: A Review of Institutional Costs of Ankle Fusion Nonunions.

Nonunion after ankle arthrodesis requiring revision is a challenging operative complication, and bone graft substitutes are costly. This study sought to summarize all institutional expenditures related to the revision of an ankle fusion nonunion, presuming that cost and skin-to-skin time would exceed those of the index surgery. The electronic records from 2 foot and ankle centers were reviewed, leading to a list of patients with 2 or more entries for tibiotalar fusions being generated. A total of 24 cases were found to match the criteria. Demographic factors and skin-to-skin time of the remaining patients were compiled. This cohort included 24 patients (6 female and 18 male) with a mean age of 64 years and body mass index of 30.4 kg/m2. Supplemental clinic visits and investigations were included either after computed tomography to assess union or 365 days after index surgery. Total cost of the revision was calculated from billing codes, length of operation, and period of hospitalization. Postrevision outpatient fees were included as well. The revisions were performed open in all cases, and 21 patients received autograft and/or bone substitute. Mean postoperative hospitalization was 3 days. The additional costs (in US dollars) associated with nonunion were $1061 for imaging, $627 for prerevision visits, $3026 for the revision, $3432 for the hospital stay, and $1754 for postrevision follow-up. The total mean amount was $9683, equivalent to 9 nights of acute inpatient stay. Mean index skin-to-skin time was 114 minutes, being 126 minutes for revisions (P=.26). Additional care related to ankle fusion nonunion represents a financial burden equivalent to 9 nights of acute inpatient stay. The use of an orthobiologic would need to be less than $436 to be cost saving. Revision surgery is not significantly longer intraoperatively than index surgery. [Orthopedics. 2020;43(4):e219-e224.].

Fusion of the Tarsometatarsal Joints: A Focus on Lateral Column Fusion Nonunion Rates

The literature has previously criticized lateral column arthrodesis, stating this procedure should be avoided to preserve biomechanical function. For patients with recurrent pain secondary to posttraumatic degenerative joint disease (PT-DJD) or dysfunction secondary to Charcot tarsometatarsal collapse, however, this procedure could provide a positive alternative to conservative measures. In our study, 37 patients underwent fourth and/or fifth metatarsal to cuboid arthrodesis, either in isolation or in combination with other tarsometatarsal arthrodeses, with an average follow-up of 27.7 ± 28.5 months. Of the 37 patients, 4 (10.8%) had purely isolated lateral column arthrodesis procedures, and 33 (89.2%) had additional fusions. Twenty patients (54.0%) were in the Charcot neuroarthropathy cohort and 17 (45.9%) in PT-DJD. Radiographs were reviewed to confirm osseous union and measure the lateral column position in both sagittal and transverse planes, using radiographic angles to measure angular correction in the transverse and sagittal planes. Postoperative patient satisfaction outcome measures were obtained via written survey, and 10-cm visual analog scale (VAS) was scored pre- and postoperatively. There was a statistically significant reduction in pain postoperatively (p < .001) and an 89% patient satisfaction rate. The incidence of revision for osseous nonunion was 10.8%. Our study shows that lateral column arthrodesis, either in isolation or combination, provides significant pain relief, high patient satisfaction, and a low incidence of revision per previous literature. This challenges past evidence-based medicine regarding lateral column fusions. The surgical procedures completed in this study suggest reproducible results with a low revision rates and high patient satisfaction for lateral column arthrodesis.

Institutional Costs Associated with Ankle Fusion Nonunion

Category: Ankle Arthritis Introduction/Purpose: Ankle arthrodesis is the most favored surgical treatment for several tibiotalar pathologies. Nonunion requiring revision occurs in 5.7% - 6.5% of patients. Nonunion is a challenging surgical complication and bone graft substitutes are costly. This study aimed to summarize all institutional expenditures related to ankle fusion nonunion needing revision, presuming that cost and skin-to-skin time would exceed that of the index surgery. Methods: Reviewing electronic charts from a foot and ankle center, a patient list with two or more entries for tibiocalcaneal, pantalar and tibiotalar fusions was generated. Out of 44 cases found, 21 patients had bilateral surgery and were excluded. Three had TAR or surgery in the periphery as index surgery; four had revision not for nonunion.Demographic factors and skin-to-skin time of the 16 remaining patients were compiled. Supplemental clinic visits and investigations were included either after CT to assess union, or 365 days post-index procedure in the absence of CT. Total cost of the revision was calculated from surgical billing codes, length of operation, and period of hospitalization. Post-revision outpatient fees were all included. This cohort included 16 patients (6F: 10 M) with an average age of 60 years (52 - 67) and BMI of 33 (29 - 38). 14 revisions were performed open; 13 patients received bone graft. Results: Average hospitalization post-operatively was 5.5 days (1.87 - 9.28). The additional cost associated with nonunion were $1,538 (CAD) for imaging, $737 for pre-revision visits, $12,483 for the revision and hospital stay, and $1,990 for post-revision follow-up. The total average amount was $14,982, equivalent to 10 nights of acute inpatient stay. Index average skin to skin time was 2:00:50 and for revisions 2:18:20, for a p-value of 0.26. The cost of nonunion per 100 primary procedures is therefore $85,397 to $97,383. If an intervention reduces the incidence of nonunion by 50% the cost saved would be $486 per procedure. As grafting or bone graft substitutes cost over $1,000, grafting should be limited to at risk patients. Conclusion: Additional care related to ankle fusion nonunion represents a financial burden equivalent to 10 nights of acute inpatient stay. Revision surgery is not significantly longer intraoperatively than index surgery. Bone graft and/or substitute should only be considered if it’s cost is less than $486 CAD at our institution.

Scoliosis and litigation

In 2010/2011, 2053 spinal infusions were carried out for scoliosis, of which 1328 were in children. In contrast there were 224 549 admissions in total for spinal disorders1 and therefore scoliosis cases proceeding to litigation are relatively uncommon. There may be other reasons for the lower incidence of litigation in scoliosis patients including the fact that almost all of these operations are carried out in tertiary centres as planned cases during daylight hours. Multidisciplinary teams of surgeons, physicians and other healthcare professionals manage the patients, and in many cases two senior surgeons operate together which may reduce the risks in these cases. Furthermore, the consenting process is generally carried out by more senior members of the team; the patients and their families are usually in no doubt that this is a major operation not without significant risk, and patients are rarely given the impression that complete correction of the deformity will take place. Although curve progression and prevention of pain are the main indications for surgery, improvement in cosmesis is also an important aim of the surgery. However, I am not aware that failure to improve appearance has been a cause for litigation. The majority of claimants in scoliosis cases are children and their families. Because many operations are carried out early in childhood, there is a very long trail of cases. Adults have to commence proceedings within three years of the perceived injury, while children have until the age of 21 to do so. In many cases the surgeon in charge of the case may be retired or may have died. The causes of allegations of negligence/breach of duty include neurological injury; failure of instrumentation or other instrumentation problems; nonunion of fusion; choice of wrong levels; failure to identify pre-operative abnormalities; failure to use spinal cord monitoring; failure …

Nonunion Risk Assessment in Foot and Ankle Surgery: Proposing a Predictive Risk Assessment Model.

Nonunion risk factor identification and modification are subjective. We describe and validate a predictive nonunion risk factor model to identify foot and ankle operative patients at risk for nonunion. One hundred international experts in foot and ankle surgery were surveyed. Nineteen nonunion risk factors were stratified into 3 categories: more significant than, as significant as, and less significant than smoking 1 pack per day. A nonunion risk assessment model was developed by assigning a weighted score to each risk factor, based on its mean score from the survey. A total nonunion risk (TNR) score was calculated for individual patients. It was retrospectively validated in 2 patient cohorts from a single center's prospectively collected end-stage ankle arthritis patient database: 22 cases of ankle and/or hindfoot fusion nonunion and 40 sex- and procedure-matched controls with bony fusion. Analyses included descriptive statistics, logistic regression, and univariate and multivariate linear regression models. The mean TNR score was 6.6 ± 5.6 in controls and 13.5 ± 8.2 in the nonunion group (P < .001). Data showed excellent intraobserver and interobserver correlation coefficients. In a logistic regression model, the risk of nonunion exceeded 9% with a TNR score greater than or equal to 10. Multivariate linear regression analysis, adjusted for age and sex, suggested that lack of fusion site stability and obesity (body mass index greater than 30) were significantly predictive of nonunion. The nonunion risk assessment model provides a reliable, sensitive, and specific method for predicting nonunion based on objective patient assessment. Orthopaedic patients at risk for nonunion could benefit from targeted intervention. Level IV, retrospective observational study.

A Prospective Pilot Study of B2A-Coated Ceramic Granules (Amplex) Compared to Autograft for Ankle and Hindfoot Arthrodesis

To reduce fusion nonunion, autogenous bone graft is often incorporated into foot and ankle fusion procedures. B2A peptide-coated ceramic granules, with encouraging results in pilot studies of transforaminal lumbar interbody fusion, were here reformulated into Amplex with a coating concentration of 225 μg B2A/cm(3) ceramic granules (B2A-granule) with the goal of eliminating autogenous bone graft in foot and ankle arthrodesis. The purpose of this study was to perform a multicenter prospective randomized pilot clinical trial designed to compare the safety and effectiveness of B2A-granule to autogenous bone graft in patients undergoing foot and ankle arthrodesis surgery. This study was a multicenter, prospective, randomized, pilot clinical trial designed to compare safety and effectiveness of B2A-granule to autogenous bone graft in patients undergoing foot and ankle arthrodesis surgery. Twenty-four patients were enrolled and randomized (1:1) into 2 groups: autogenous bone graft control and B2A-granule. Primary outcome measures at 6 months (with follow-up at 9 and 12 months) included radiographic fusion assessed by computerized tomography and Ankle Osteoarthritis Scale scores for pain and disability. Radiographic fusion success rates were similar in both groups (100% in the B2A-granule group, 92% autograft). Both the B2A-granule group and the autograft group had improvements in the pain and disability scores over the course of the study. Graft harvest-site pain affected only autograft-treated patients. There were no adverse events attributed to the graft material in either the B2A-granule or autograft group. The results of this pilot study are supportive of a larger clinical trial to assess the safety and efficacy of B2A-granule as a bone graft substitute in foot and ankle fusions. Level II, prospective comparative study.

The use of bone morphogenetic protein-6 gene therapy for percutaneous spinal fusion in rabbits.

Fusion procedures in the lumbar spine have been performed in the US since 1911. Since that time, the indications and techniques for spinal fusion have evolved. Despite technical advancements, spinal fusion remains a major operation, and fusion nonunion rates of up to 35% are still reported. In this study, the authors were able to induce intertransverse process fusions in immune-competent New Zealand White rabbits by percutaneous administration of an adenoviral vector containing the bone morphogenetic protein (BMP-6) gene (Ad-BMP-6). The results represent an important step forward in finding new methods to increase the success and decrease the morbidity associated with spinal fusion. Five New Zealand White rabbits were used. Injection of the adenoviral construct was performed at multiple levels (bilaterally) in each animal while using fluoroscopic guidance. Injection consisted of either Ad-BMP-6 or Ad-beta-galactosidase (beta-gal) (control). Because multiple levels were injected, each animal served as an internal control. The animals underwent postinjection computerized tomography (CT) scanning at 7 and 14 weeks. After undergoing final CT scanning, the animals were killed and the spines were harvested. The fusion sites were analyzed by gross inspection, histopathological methods, and micro-CT studies. The results of this study show that an anatomically precise fusion can be accomplished by percutaneous administration of gene therapy. The next step in these studies will be extension of the technique to nonhuman primates and eventually to human clinical studies.