BACKGROUND: Failure to fuse following anterior cervical discectomy and fusion (ACDF) may result in symptomatic pseudoarthrosis. Traditional diagnosis involves computerized tomography to detect bridging bone and/or flexion-extension radiographs to assess whether segmental motion is above specific thresholds; however, there are currently no well-validated diagnostic tests. We propose a biomechanically rational approach to achieve a reliable diagnostic test for pseudoarthrosis.
OBJECTIVE: Develop and test a biomechanically based approach to the diagnosis of pseudoarthrosis.
METHODS: Literature review, development of theory, re-analysis of a previously published study with surgical exploration as the gold-standard, and retrospective analysis of pooled studies to understand time to fusion.
METHODS: Fully automated methods were used to measure disc space strains (change in disc space height divided by initial height). Measurement error combined with the reported failure strain of trabecular bone led to a proposed strain threshold for diagnosis of pseudoarthrosis following ACDF. We reanalyzed previously reported flexion-extension radiographs for asymptomatic volunteers to assess whether flexion-extension radiographs, in the absence of fusion surgery, can be expected to provide sufficient stress on motion segments to allow for reliable strain-based fusion assessment. The sensitivity and specificity of strain- and rotation-based pseudoarthrosis diagnosis were assessed by reanalysis of previously reported post-ACDF flexion-extension radiographs, where intraoperative fusion assessments were also available. Finally, we assessed changes in strain over time using 9,869 flexion-extension radiographs obtained 6 weeks to 84 months post-ACDF surgery from 1,369 patients.
RESULTS: The estimated error in automated measurement of disc space strain from radiographs was approximately 3%, and the reported failure strain of bridging bone was less than 2.5%. On that basis, we propose a 5% strain threshold for pseudoarthrosis diagnosis. Reanalysis of a study in which intraoperative fusion assessments were available revealed 67% sensitivity and 82% specificity for strain-based diagnosis of pseudoarthrosis, which was comparable to rotation-based diagnosis. Analysis of post-ACDF flexion-extension radiographs revealed rapid strain reduction for up to 24 months, followed by a slower decrease for up to 84 months. When rotation is less than 2 degrees, the strain-based diagnosis differed from the rotation-based diagnosis in approximately 14% of the cases.
CONCLUSIONS: We propose steps for standardizing diagnosis of pseudoarthrosis based on the failure strain of bone, measurement error, and retrospective data. These steps include obtaining high-quality flexion-extension studies, the application of proposed diagnostic thresholds, and the use of image stabilization for conclusive diagnosis, when motion is near thresholds. The necessity for an accurate diagnosis with minimal radiation exposure underscores the need for further optimization and standardization in diagnosing pseudoarthrosis following ACDF surgery.
CONCLUSIONS: In a symptomatic post-spine fusion patient, it is important to diagnose or rule-out pseudoarthrosis. There are currently no well-validated diagnostic tests for this condition. Incorporating strain-based intervertebral motion analysis into the diagnosis could lead to a standardized and validated test for detecting spine pseudoarthrosis.

The use of cannabis as a method of chronic pain relief has skyrocketed since its legalization in states across the United States. Clinicians currently have a limited scope regarding the effectiveness of marijuana on surgical procedures. This systematic review aims to determine the effect of current cannabis use on the rate of failure of spinal fusions and overall surgical outcomes. A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statement. PubMed, Embase, and Scopus were searched, identifying studies assessing spinal fusion with reported preoperative cannabis use. Outcomes of interest included reoperation due to fusion failure or pseudoarthrosis with a follow-up time of at least six months. Subgroups of cervical fusions alone and lumbar fusions alone were also analyzed. Certainty in evidence and bias was assessed using the GRADE criteria and ROBINS-I tool (PROSPERO #CRD42023463548). Four studies met the inclusion criteria, with a total of 788 patients (188 in the cannabis user group and 600 in the non-user group). The rate of revision surgery among cannabis users was higher than that in non-users for all spinal fusions (RR: 3.58, 95% CI: 1.67 to 7.66, p = 0.001). For cervical fusions alone, there remained a higher rate of revision surgery for cannabis users compared to non-users (RR: 4.47, 95% CI: 1.93 to 10.36, p = 0.0005). For lumbar fusions alone, there was no difference in the rates of revision surgery between cannabis users and non-users (RR: 1.21, 95% CI: 0.28 to 7.73, p = 0.79). Cannabis use was shown to be associated with a higher rate of pseudoarthrosis revisions in spinal fusions on meta-analysis. On subgroup stratification by spine region, cannabis use remained associated with pseudoarthrosis revisions on cervical fusions alone but not lumbar fusions alone. Further research with larger, randomized studies is required to fully elucidate the relationship between cannabis use and fusion, both in general and by spinal region.

BACKGROUND: Atrophic pseudoarthrosis is a serious complication with an incidence of 5-10 % of bone fractures located in the diaphysis of long bones. Standard treatments involve aggressive surgical procedures and re-interventions requiring the use of autografts from the iliac crest as a source of bone-forming biological activity (Standard of Care, SoC). In this context, regenerative ex vivo expanded osteogenic cell-based medicines could be of interest. Particularly, Mesenchymal Stromal Cells (MSC) offer new prospects to promote bone tissue repair in pseudoarthrosis by providing biological activity in an osteoconductive and osteoinductive environment.
METHODS: We conducted a phase IIa, prospective, randomised, parallel, two-arms, open-label with blinded assessor pilot clinical trial to compare SoC vs. a tissue-engineered product (TEP), composed of autologous bone marrow (BM)-derived MSCs loaded onto allogeneic decellularised, lyophilised spongy bone cubes, in a cohort of 20 patients with non-hypertrophic pseudoarthrosis of long bones. Patients were followed up for 12 months. Radiological bone healing was evaluated by standard X-ray and computed tomography (CT) scanning. Quality of life was measured using the EUROQOL-5D questionnaire.
RESULTS: Ten patients were randomized to TEP and 10 to SoC with iliac crest autograft. Manufacturing of TEP was feasible and reproducibly achieved. TEP implantation in the bone defect was successful in all cases and none of the 36 adverse events (AE) reported were related to the treatment. Efficacy analyses were performed in the Full Analysis Set (FAS) population, which included 17 patients after 3 patients withdrew from the study. The degree of consolidation, estimated by measuring Hounsfield units (HU) on CT, showed no significant differences between the two treatment groups at 12 months post treatment (main efficacy variable) (p = 0.4835) or at 6 months.
CONCLUSIONS: Although only a small number of patients were included in our study, it is notable that no significant differences were observed between the experimental treatment and SoC, thus suggesting TEP as an alternative where autograft is not available or contraindicated.

Forearm fractures are the most common type of fractures in pediatric age. As children have excellent healing potential, fracture nonunion is a very uncommon complication. Elastic intramedullary nailing, a minimally invasive technique, is an excellent treatment modality for the unstable forearm shaft fractures in children, which can seldom lead to nonunion. Here, we present a case of hypertrophic pseudoarthrosis of mid shaft of ulna in a 13-year-old male, which healed spontaneously with elastic stable intramedullary nailing in situ.

BACKGROUND: In case of high sacral slope, anterior lumbosacral fusions can be performed by retroperitoneal or transperitoneal approach using a reversed Bohlman technique with an autologous corticocancellous fibular graft. The use of a trans-lumbosacral implant can avoid the iatrogenic effects but currently, there is no implant specifically designed for this fusion technique. Could the IFUSE implant from SI BONE replace a fibular graft to avoiding the iatrogenic effect induced by sampling during a Reverse Bohlman technique?
METHODS: We present the case of a 38-year-old woman with L5S1 interbody pseudarthrosis after posterior fixation for grade 2 L5-S1 spondylolisthesis with isthmic lysis of L5, and that of a 69-year-old woman who underwent a posterior T4 fusion to the pelvis for degenerative scoliosis. Both required a trans-lumbosacral instrumented fusion via an anterior approach using the reverse Bohlman technique. Surgical technique was described.
RESULTS: There were no perioperative or postoperative complications. At 6 months, the patients reported a decrease in lumbar and radicular symptomatology. There were no infectious, neurological or vascular complications. CT-scans confirmed the good position and stability of the IFUSE implant.
CONCLUSIONS: We present an innovative interbody grafting technique adapted to spines with high pelvic incidence. The surgical technique is safe, minimally invasive, and reduces surgical iatrogeny. The short and medium-term results are positive but require longer-term follow-up and a larger cohort.

Bilateral cages are often used for interbody fusion. However, this procedure may not be possible in some cases making unilateral cages a reasonable alternative. The literature remains divided on the clinical and radiological distinctions when comparing unilateral to bilateral cages in lumbar interbody fusion. Thus, this meta-analysis will analyze the clinical and radiographic outcomes between these 2 groups.
PubMed, Cochrane, and Google Scholar (page 1-20) were searched till January 2024. The clinical outcomes evaluated were the incidence of adverse events, surgery-related parameters, and patient reported outcomes.
Lower rates of pseudoarthrosis, subsidence, were reported in the bilateral cages group (P = 0.01, P = 0.001, respectively) whereas shorter operative time (OR time), and lower estimated blood loss were seen in unilateral cage group (P < 0.001, and P = 0.003). There was no statistically significant difference in the remaining analyzed outcomes.
Unilateral cages were shown to be superior due to their reduced OR time and estimated blood loss. As for the higher rate of pseudoarthrosis, this outcome may not be related to the cage numbers and it did not affect clinical outcomes. Nevertheless, one must consider other factors such as radiographic sagittal parameters before making a surgical decision.

The aims of this study were to retrospectively assess the occurrence of complications or need for secondary wrist procedures after the Sauvé-Kapandji procedure, and to prospectively assess patient-reported outcomes at long-term follow-up. All patients treated with the Sauvé-Kapandji procedure in our tertiary referral hospital between January 2008 and September 2021 were identified and contacted to complete the Quick Disabilities of the Arm, Shoulder, and Hand and the Patient-Rated Wrist/Hand Evaluation outcome measures. In total, 30 patients, with a median follow-up of 82 months, were included in this study. Complications occurred in 6 of 30 patients, which resulted in six secondary wrist procedures. Mean Quick Disabilities of the Arm, Shoulder, and Hand and Patient-Rated Wrist/Hand Evaluation scores were 30.1 and 33.6, respectively. We conclude that in respect of long-term outcomes, the Sauvé-Kapandji procedure can still be deemed to be a useful procedure, especially in patients with few other reconstructive options.Level of evidence: IV.

BACKGROUND: bone defects drastically alter the patient\'s quality of life, and can produce serious sequelae such as dysfunctional shortening, angular deformity, joint stiffness and irreversible gait disorder.
OBJECTIVE: to describe the experience of managing post-traumatic bone defects of long bones treated with the membrane induction technique.
METHODS: retrospective observational study of patients with bone defects greater than 3 cm in diaphyseal pseudoarthrosis of long bones, who underwent the Masquelet technique. Period taken from January 2019 to January 2021. All patients underwent vigorous debridement and stabilization of the fracture, to then place the cement spacer. Spacer removal was at 4-6 weeks. The degree of consolidation was assessed, as well as the evolution of the treatment.
RESULTS: 25 patients were included in the study; the mean age was 36.8 ± 8.9 years. Diameter of bone losses was 3 to 10 cm (84%) and > 10 cm (16%). Bone consolidation occurred in patients with a defect < 10 cm (16%). 32% of patients presented some complication.
CONCLUSIONS: bone union was achieved only in a few patients with defects smaller than 10 cm, requiring alternative procedures in most cases. Proper selection of patients is required.
UNASSIGNED: los defectos óseos alteran drásticamente la calidad de vida del paciente y pueden producir serias secuelas como acortamiento disfuncional, deformidad angular, rigidez articular y trastorno irreversible de la marcha.
OBJECTIVE: describir la experiencia clínica en el manejo de defectos óseos postraumáticos de huesos largos tratados con la técnica de inducción de membrana.
UNASSIGNED: estudio observacional, retrospectivo, de pacientes con defectos óseos mayores de 3 cm con pseudoartrosis diafisaria de huesos largos, a los que se aplicó la técnica de Masquelet. En el período de Enero de 2019 a Enero de 2021. A todos los pacientes se les realizó desbridamiento enérgico y estabilización de la fractura, para posteriormente colocar el espaciador de cemento. El retiro del espaciador fue a las 4-6 semanas. Se valoró el grado de consolidación y la evolución del tratamiento.
RESULTS: se incluyeron 25 pacientes, la media de edad fue de 36.8 ± 8.9 años. El diámetro de las pérdidas óseas fue de 3 a 10 cm (84%) y > 10 cm (16%). La consolidación ósea se presentó en pacientes con un defecto < 10 cm (16%). Treinta y dos por ciento de los pacientes presentó alguna complicación.
CONCLUSIONS: la consolidación ósea se logró sólo en aquellos pacientes con defectos < 10 cm, requiriendo procedimientos alternativos a la técnica de inducción de membrana en la mayoría de los casos. Se requiere una selección adecuada de pacientes para lograr la consolidación ósea por medio de esta técnica.

Pseudoarthrosis of the tibia is an uncommon condition that occurs due to non-union of bone and typically requires surgery. It may cause fractures that develop spontaneously or after minor trauma. Physiotherapy is an excellent treatment for this uncommon condition. The tibia of the affected limb becomes malformed and bends backwards. This case report outlines the interdisciplinary programme adopted to successfully manage a 23-year-old female patient with right-sided tibial pseudoarthrosis. Following the implantation of Ilizarov\'s external fixator to correct the deformity, the patient was referred to the physiotherapy department for post-operative management. After the implementation of a tailor-made physiotherapy protocol focusing on proprioceptive retraining, significant improvements were seen in her joint proprioception, muscular strength and range of motion.

The purpose of the study was to investigate whether arthroscopic treatment of carpal scaphoid nonunions by osteosynthesis with bone grafting represents a successful surgical technique. This systematic literature review, conducted following the PRISMA guidelines, explores the past 10 years of clinical studies concerning the arthroscopic treatment of scaphoid nonunions. The most relevant keywords were used to search the databases, and the Downs and Black 27-item checklist has been used as quality assessment tool. Twelve papers that meet the premised eligibility criteria have been identified. These studies demonstrate the efficacy of this surgical solution, achieving a postoperative union rate of 96% in the average time of 13.5 weeks. Regardless of the method of synthesis and the origin of the graft used, excellent results were obtained. Patients who underwent this procedure reported a pain reduction of almost 80% compared to the preoperative level, improvement in grip strength close to 40%, and recovery in wrist function during daily activities. Arthroscopy has numerous advantages compared to the open approach. These are technically recognized by the surgeon and by the patient. Some disadvantages include a longer intraoperative time and considerable significant technical difficulty. Arthroscopic treatment of scaphoid nonunion by osteosynthesis with bone graft achieves a 96% union rate of the treated scaphoid with satisfying clinical results.