Survival and functional outcomes following surgical repair of pathological fractures in dogs: A meta-analysis

Abstract

Background: Pathological fractures result from abnormal bone remodeling caused by local bone lesions, such as malignant tumors, compromising bone strength. Tumor-derived factors disrupt the balance between bone resorption and formation, leading to osteolytic and osteosclerotic lesions that weaken bone integrity. While surgical treatments, including limb amputation and limb-sparing surgery, are commonly used, the therapeutic efficacy of fracture repair remains unclear due to limited evidence.

Aim: This study characterized pathological fractures and evaluated survival time and functional prognoses following surgical repair in dogs. The goal was to provide robust evidence to inform clinical decision-making and improve treatment outcomes.

Methods: A systematic review and meta-analysis were conducted following a PRISMA-compliant approach. MEDLINE (PubMed) and Google Scholar were used to search for relevant studies published from database inception to March 1, 2025. Data from past reports were integrated with cases from our institution, comprising 70 dogs with pathological fractures. Survival and prognosis were analyzed using the Kaplan-Meier method, and outcomes between adjuvant chemotherapy were compared using the log-rank test.

Results: Osteosarcoma was the most common cause of pathological fractures (n = 55; 78.6%), followed by multiple myeloma, undifferentiated sarcoma, and bone metastases. Surgical stabilization was the most common therapeutic intervention (n = 40; 57.1%), with plate stabilization being the most frequently used technique (n = 20; 28.6%). The median time to lameness recurrence was 163 days (95% confidence interval [CI]: 130-510 days), while the median survival time with osteosarcoma was 292 days (95% CI: 163-518 days). The subgroup analysis revealed no significant difference in survival between patients who received adjuvant therapy (radiation therapy or chemotherapy) and those who did not (p = 0.675). Clinical and statistical heterogeneities were not assessed due to the integration of case reports and case series.

Conclusion: Surgical stabilization of pathological fractures resulting from osteosarcoma should be considered a palliative treatment option for cases in which amputation is declined by the owner or in dogs with advanced disease, including metastatic lesions. With appropriate patient selection, this approach may represent a viable third-line treatment following limb-sparing surgery and amputation.

Keywords: Fracture repair; Meta-analysis; Osteosarcoma; Palliative treatment; Pathological fracture.

Fig. 1.. PRISMA flow diagram.

Fig. 2.. Descriptive analysis results. Clinical data from 70 cases are summarized using pie charts. (A) The cause of the pathological fracture, (B) the affected location, (C) clinical management, and (D) the type of implant used at the time of surgery.

Fig. 3.. (A) Kaplan–Meier curves illustrate functional prognosis after surgery, defined as the number of days from fracture repair until lameness is observed, as evaluated by orthopedic veterinarians. Tick marks indicate censoring events, such as euthanasia or natural death. (B) Kaplan–Meier curves depicting survival analysis for patients with osteosarcoma, with tick marks indicating censoring events, such as euthanasia. (C) Pie chart showing subgroup analysis results comparing cohorts with or without adjuvant therapy. (D) Kaplan–Meier curves comparing functional prognosis between patients who received adjuvant therapy (black line) and those who did not (red line).