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Purpose: Although complications are known to affect mortality in patients with spinal cord compression (MSCC), the impact of specific complication subtypes on survival and their risk factors remain poorly defined. The aim was to identify risk factors for perioperative and postoperative local and systemic complications in patients who underwent surgery for MSCC and to evaluate their association with postoperative survival.

Methods: We retrospectively analyzed 256 patients who underwent surgical treatment for MSCC between 2003 and 2022. Complications occurring within 30 days postoperatively were classified as perioperative, postoperative local, or postoperative systemic complications. Associations between complications and patient-related variables (age, comorbidities, smoking status, performance status, preoperative ambulatory status, and prior radiotherapy) and surgery-related variables (approach, intraoperative blood loss, and duration of surgery) were examined.

Results: At least one complication occurred in 86 patients (33,6%): 14 perioperative, 39 systemic, and 33 local complications. Postoperative systemic complications (HR 1.8, 95% CI 1.2–2.5; p = 0.003) and lower performance status (HR 1.9, 95% CI 1.4–2.6; p < 0.001), were independently associated with reduced postoperative survival. Impaired preoperative ambulatory function was associated with postoperative complications (HR 2.1, 95% CI 1.0–4.3; p = 0.04).

Conclusion: Postoperative systemic complications were associated with reduced survival following surgery for MSCC. Impaired preoperative ambulatory function increases the risk of complications and should be emphasized in preoperative risk assessment and surgical decision-making.

Purpose: The risk of re-fracture after implant removal in healed hip fractures remains a clinical concern. This study aimed to determine the incidence of re-fracture following implant removal after osteosynthesis of a hip fracture.

Methods: We conducted a retrospective multicenter cohort study including patients aged ≥ 50 years who underwent implant removal between 2003 and 2023 after radiologically confirmed consolidation of a hip fracture. Patients were identified using procedural codes. Baseline variables included age, sex, ASA classification, fracture type (femoral neck or trochanteric), and implant type (pins/screws, sliding hip device [SHD], or short/long cephalomedullary nail [CMN]). Patients were followed from implant removal until re-fracture, conversion to arthroplasty, death, or end of follow-up, with a minimum follow-up of 1 year. Cox proportional hazards regression was used to assess associations between implant type and re-fracture risk, adjusting for age and sex. Because the proportional hazards assumption was violated, a time-stratified Cox regression and restricted mean survival time analyses were applied.

Results: A total of 575 patients (median age 73 years, IQR 65–81) were included, with a median follow-up of 53 months (IQR 18–100). Lateral hip pain was the most common indication for implant removal (72.5%). The overall re-fracture incidence was 10.4%. Risk varied by implant type: 7.1% after pins/screws, 10.5% after SHD, 18.3% after short CMN, and 15.8% after long CMN removal. Median time to re-fracture was 1.5 months, and 52% occurred after minimal or no trauma. Most re-fractures (85%) occurred within 90 months. Removal of CMNs was associated with a higher re-fracture risk compared with pins/screws (HR 2.79; 95% CI 1.52–5.13), whereas SHD removal was not.

Conclusion: Implant removal after consolidated hip fractures carries a measurable risk of re-fracture, most pronounced after CMN removal. These findings highlight the importance of careful patient selection and could aid in decision-making when considering implant exchange or removal following osteosynthesis.

Levels of evidence: IV, retrospective observational cohort study.

This nationwide register-based cohort study examined the association between castration status and postoperative survival in men who had undergone surgery for spinal metastases from prostate cancer. Bone metastases are common in prostate cancer, with the spine being the most frequent site. Using data from the Swedish Spine Register (Swespine) and Prostate Cancer Database Sweden (PCBaSe), 306 men with prostate cancer who underwent spinal surgery were identified. In total, 81 were categorized as castration-sensitive and 225 as castration-resistant disease at the time of spinal surgery. Postoperative survival was estimated using Kaplan-Meier analysis and compared with the log-rank test. Multivariable Cox regression was used to adjust for potential confounders. Median survival after surgery was significantly longer in men with castration-sensitive prostate cancer (33 months, IQR 15-55) compared to those with castration-resistant disease (8 months, IQR 5-31; p < 0.001). Castration-sensitive status was independently associated with a lower risk of death (hazard ratio 0.29, 95% CI: 0.20-0.41). These findings indicate that castration sensitivity is a strong prognostic factor for survival after surgery for spinal metastases from prostate cancer and should be considered in surgical decision-making.

Study Design: Retrospective cohort study.

Objective: Spinal metastases are common in patients with breast cancer, and accurate estimation of postoperative survival is crucial for selecting appropriate candidates for metastasis surgery. This study investigated the association between breast cancer subtype, according to the St. Gallen classification, and survival after surgery for spinal metastases with the aim of improving prognostic assessment and supporting informed patient counselling.

Methods:: This study included 110 patients with breast cancer who underwent surgery for spinal metastases identified from the Swedish Spine Register and the Swedish National Quality Register of Breast Cancer. Patients were categorized in terms of the breast cancer subtype according to the St. Gallen classification. Postoperative survival was analysed using Kaplan-Meier estimates and a Cox proportional hazards model.

Results: The overall median survival following spinal surgery was 25 months (95% CI 19-31), while the median postoperative survival by subtype was 39 months (95% CI 28-50) for luminal A patients, 20 months (95% CI 9-31) for luminal B patients, and 48 months (95% CI 20-76) for luminal B/HER2+ patients. The median survival was not reached for the nonluminal HER2+ group, whereas patients with triple-negative breast cancer had a median survival of only 5 months (95% CI 4-6). The St. Gallen subtype was significantly associated with postoperative survival according to univariable (P<0.001) and multivariable analyses (P = 0.011).

Conclusions: Breast cancer subtype according to the St. Gallen classification was significantly associated with survival after surgery for spinal metastases. These findings indicate that the St. Gallen classification may serve as a valuable prognostic tool in the metastatic spine setting. Incorporation of molecular subtype information may improve estimation of postoperative survival and support informed patient counselling, expectation management, and individualized surgical decision-making in patients with breast cancer spinal metastases.

Background and purpose: The design and coating of uncemented joint implants impact bone ingrowth and thereby the stability of the implant. This prospective randomized clinical trial aimed to compare early migration of two uncemented, similarly shaped femoral stems with either calcium phosphate or hydroxyapatite coating.

Patients and methods: 93 patients (102 hips) were randomized to either an intervention calcium phosphate or a conventional hydroxyapatite-coated stem. Migration measurements were performed postoperatively, and at 6 weeks, 3, 12 months, and 2 and 5 years after operation, and analyzed with radiostereometric analysis.

Results: There were no significant differences in migration between the two stems from postoperative to 5-year follow-up. With 6 weeks follow-up as baseline, the calcium phosphate coated stem showed a tendency towards migrating less with a maximum total point motion up to 2 years of 0.84 mm (0.68 to 1.00 95% CI) compared to the hydroxyapatite-coated stem which migrated 1.25 mm (0.99 to 1.52 95% CI) (P = 0.010).

Conclusions: Our data show that the calcium phosphate-coated stem is a safe implant in terms of ingrowth stability, and with migration patterns comparable to a hydroxyapatite-coated stem.

Background and purpose — Sonication fluid cultures have been proposed as a complementary diagnostic method to intraoperative tissue culture sampling for the diagnosis of periprosthetic joint infection (PJI). We evaluated whether sonication provides additional clinically relevant information in the diagnosis of PJI in hip revision.

Methods — Episodes of hip revision performed between January 2007 and December 2016 were assigned retrospectively to the European Bone and Joint Infection Society (EBJIS) definition of periprosthetic joint infection: infection unlikely, infection likely, and infection confirmed. The inclusion criteria were a minimum of 2 perioperative tissue cultures collected at the index procedure and sonication performed on a removed implant. The results of the tissue cultures were compared with the results of the implant sonication fluid cultures (SFCs).

Results — 288 hip revision episodes in 250 patients fulfilled the inclusion criteria and were analyzed. The “infection unlikely” group included 203 episodes (178 patients), the “infection likely” group included 5 episodes (5 patients), and the “infection confirmed” group included 80 episodes (67 patients). SFC delivered additional clinical information in 15/288: 6 of 203 episodes in the “infection unlikely” group, 2 of 5 episodes in the “infection likely” group, and 7 of 80 in the “infection confirmed” group. Coagulase-negative staphylococci and Staphylococcus aureus were the dominant bacterial species in both the SFC and tissue cultures.

Conclusion — In addition to tissue cultures, sonication fluid cultures optimized the microbiological yield in 15 out of 288 hip revision episodes.

We previously identified three molecular subtypes of prostate cancer (PC) bone metastases, MetA-C, with MetB linked to poor prognosis after androgen deprivation therapy (ADT). This study analyzed epithelial and stromal markers using immunohistochemistry, focusing on their relationship to MetA-C subtypes, spatial heterogeneities, and clinical outcomes after ADT. High tumor proliferation and low PSA expression were associated with MetB and poor outcomes after ADT. Most metastases contained tumor epithelial subclones with different morphologies. In the metastasis stroma, blood vessels and fibroblast-like cells expressed smooth muscle actin (SMA), platelet-derived growth factor β, stroma-derived factor 1 (SDF1), periostin (POSTN), and decorin (DCN). Compared to each other, MetB metastases had higher SMA and ERG + endothelial cell densities, while MetA cases showed higher SDF1 and DCN levels. Accordingly, high POSTN and ERG + densities were associated with poor outcomes after ADT, whereas high DCN indicated favorable prognosis. Low levels of AR-positive stromal cells were linked to poor outcomes. Macrophage and T-lymphocyte densities showed no significant associations with metastases subtypes or outcome. Two stroma subtypes were identified: subtype 1 with higher bone content, lower vessel density, MetA-enrichment and better prognosis compared to subtype 2 that exhibited higher tumor proliferation and lower PSA expression. Most metastases contained regions of both stroma subtypes.

PURPOSE: We aimed to identify predictors of ambulation recovery in patients who lost their ability to walk for more than 48 h due to metastatic spinal cord compression (MSCC).

METHODS: This was a retrospective cohort study of 121 patients with MSCC who underwent surgery. The primary outcome variable was postoperative ambulatory status. The secondary outcome variable was postoperative survival in relation to restored ambulation. Age, primary tumor grade, MSCC anatomical location, Karnofsky performance status (KPS), Charlson comorbidity index, neurological deterioration speed, MSCC grade according to the epidural spinal cord compression scale, anal sphincter tonus and hip flexion strength before surgery, and postoperative complications were analyzed as predictive variables.

RESULTS: One month after surgery, ambulation was restored in 61 of the 111 patients (55%), 10 patients died within one month after surgery. Primary tumor grade (p = 0.03), hip flexion strength before surgery (p < 0.001), and postoperative complications (p = 0.001) were associated with ambulation recovery. The accuracy of hip flexion strength as a predictor was analyzed with a receiver operating characteristic (ROC) curve, with an area under the curve of 0.74 (p < 0.001). The median postoperative survival of patients who regained ambulation was 16 months, whereas that of patients who lost walking ability was 5 months (p = 0.004). According to the multiple Cox regression model, KPS (p < 0.001) and ambulation after surgery (p = 0.027) were predictors of postoperative survival.

CONCLUSIONS: Primary tumor grade, hip flexion strength before surgery, and surgical complications affect neurological recovery in MSCC patients who had lost their ability to walk for more than 48 h.

Background and purpose: Pathologic and impending fractures occur in patients with advanced metastatic disease and necessitate surgical interventions with high risk of complications. The aim of this study was to analyze the efficacy of combined treatment with denosumab and radiotherapy as an alternative to surgery in treating bone metastases of the pelvis and extremities.

Methods: This retrospective cohort study included 38 patients with impending and pathologic fractures due to carcinoma metastases who received monthly injections of denosumab (120 mg/dose) and radiotherapy. Twenty-three patients received denosumab and single-dose radiotherapy of 8 Gy, and 15 patients received denosumab and fractionated radiotherapy. We assessed pain, radiographic signs of fracture healing, survival and complications.

Results: Of the 38 patients 36 experienced pain reduction. Callus formation was observed in 11/17 patients with pathologic fractures, and increased mineralization was found in 12/21 patients with impending fractures. In 23/38 patients, we found both pain reduction and callus formation or increased mineralization. There were no statistically significant differences in treatment outcomes between the patients who received denosumab and single-dose radiotherapy and those who received denosumab and fractionated radiotherapy. The survival rates at 30 days and 1 year were 95% and 56%, respectively.

Interpretation: Combined treatment with denosumab and radiotherapy may reduce pain and promote bone healing in patients with metastatic impending and pathologic fractures. In this combined treatment, the effect of single-dose radiotherapy appears to be comparable to that of fractionated regimens.

Background: Uncemented trabecular metal (TM) monoblock tibial components in total knee arthroplasty (TKA) have shown excellent clinical results for up to 10 years. However, these studies were performed in highly specialized units, with few surgeons and often excluding knees with secondary osteoarthritis (OA), severe malalignments and previous surgery. The purpose of this study was to investigate implant survivorship and clinical and radiological outcome of the uncemented TM high-flex posterior stabilized (PS) monoblock tibial component in routine clinical practice.

Methods: A retrospective study of 339 knees (282 patients) operated with the implant in routine clinical practice at two hospitals on patients aged 60 years or younger between 2007 and 2015. The operations were performed by 12 surgeons and there were no specific contraindications for use of the implant. Follow up ended in 2020. The status of the implant of deceased patients at death and those not attending follow up was checked with the Swedish Knee Arthroplasty Register. Clinical follow up consisted of clinical investigation, PROMs, and knee X-ray.

Results: Follow up was mean (range) 8.5 (5–13.8) years, and the 8-year survival rate was 0.98 (standard error 0.007). Five patients five knees) were deceased, five knees were revised (none due to aseptic loosening), and 16 patients did not attend the clinical follow up. Forty-four percent of the knees had secondary OA and 45% had had previous operations. 93% were satisfied or very satisfied with the operation and forgotten joint score (FJS) was median (interquartile range) 81 (44–94). Radiographic analysis revealed bone in close contact with the tibial tray and pegs in most cases, and in only 2% of the knees were potential radiolucent lines found.

Conclusion: The results indicate that this uncemented implant performs excellently in routine clinical practice and also in younger patients with secondary OA or previous knee operations.