Outcomes of Nonoperatively Treated Vancouver B1 Fractures: Is Failure Common?

BACKGROUND: Periprosthetic fractures (PPFx) are a severe complication of total hip and hemiarthroplasty. Surgical treatment is typically performed but can result in major morbidity. Nonoperative PPFx management may provide a successful treatment alternative in select patients. METHODS: Vancouver B1 PPFx patients treated over a 10-year period were identified. Patient demographic data were retrospectively recorded. Injury and postoperative radiographs were reviewed. There were 48 patients who met the study criteria. Patients were divided into operative and nonoperative comparative cohorts. Outcome comparisons between the 2 cohorts included 1-year mortality, unplanned surgery within 24 months of injury, fracture union rate, and return to preinjury ambulation status. RESULTS: There was no difference in 1-year mortality between the nonoperative and operative cohorts (17 versus 8%; P = .32). We found no significant difference in unplanned surgery between the nonoperative and operative groups (8.7 versus 12%; P = .71), fracture union (100 versus 96%, P = .34), or return to ambulation status (86 versus 91%; P = .86). Nonoperative fractures were minimally displaced and within the metaphyseal region of the proximal femur without stem subsidence. Nonoperative fractures with subsequent treatment failure had initial fracture extension closer to the tip of the stem compared to successfully treated nonoperative fractures (5.5 versus 10.2 centimeters; P = .02). CONCLUSION: Select nonoperatively treated patients had infrequent need for unplanned surgery, high union rate, and return to their preinjury ambulation status. Nonoperative management is not appropriate for all Vancouver B1 PPFx, but those patients who have minimally displaced meta-diaphyseal fractures and partial remaining distal fixation can be successfully treated.

Investigation of multiphasic 3D-bioplotted scaffolds for site-specific chondrogenic and osteogenic differentiation of human adipose-derived stem cells for osteochondral tissue engineering applications.

Osteoarthritis is a degenerative joint disease that limits mobility of the affected joint due to the degradation of articular cartilage and subchondral bone. The limited regenerative capacity of cartilage presents significant challenges when attempting to repair or reverse the effects of cartilage degradation. Tissue engineered medical products are a promising alternative to treat osteochondral degeneration due to their potential to integrate into the patient's existing tissue. The goal of this study was to create a scaffold that would induce site-specific osteogenic and chondrogenic differentiation of human adipose-derived stem cells (hASC) to generate a full osteochondral implant. Scaffolds were fabricated using 3D-bioplotting of biodegradable polycraprolactone (PCL) with either ß-tricalcium phosphate (TCP) or decellularized bovine cartilage extracellular matrix (dECM) to drive site-specific hASC osteogenesis and chondrogenesis, respectively. PCL-dECM scaffolds demonstrated elevated matrix deposition and organization in scaffolds seeded with hASC as well as a reduction in collagen I gene expression. 3D-bioplotted PCL scaffolds with 20% TCP demonstrated elevated calcium deposition, endogenous alkaline phosphatase activity, and osteopontin gene expression. Osteochondral scaffolds comprised of hASC-seeded 3D-bioplotted PCL-TCP, electrospun PCL, and 3D-bioplotted PCL-dECM phases were evaluated and demonstrated site-specific osteochondral tissue characteristics. This technique holds great promise as cartilage morbidity is minimized since autologous cartilage harvest is not required, tissue rejection is minimized via use of an abundant and accessible source of autologous stem cells, and biofabrication techniques allow for a precise, customizable methodology to rapidly produce the scaffold.

Deferoxamine-Soaked Suture Improves Angiogenesis and Repair Potential After Acute Injury of the Chicken Achilles Tendon.

BACKGROUND: A major obstacle to the treatment of soft tissue injuries is the hypovascular nature of the tissues. Deferoxamine (DFO) has been shown to stimulate angiogenesis by limiting the degradation of intracellular hypoxia-inducible factor 1-alpha. HYPOTHESIS: DFO-saturated suture would induce angiogenesis and improve the markers of early healing in an Achilles tendon repair model. STUDY DESIGN: Controlled laboratory study. METHODS: Broiler hens were randomly assigned to the control (CTL) group or DFO group (n = 9 per group). The right Achilles tendon was partially transected at its middle third. The defect was surgically repaired using 3-0 Vicryl suture soaked in either sterile water (CTL group) or 324 mM DFO solution (DFO group). All animals were euthanized 2 weeks after the injury, and the tendon was harvested. Half of the tendon was used to evaluate angiogenesis via hemoglobin content and tissue repair via DNA content and proteoglycan (PG) content. The other half of the tendon was sectioned and stained with hematoxylin and eosin, safranin O, and lectin to evaluate vessel density. RESULTS: Hemoglobin content (percentage of wet tissue weight) was significantly increased in the DFO group compared with the CTL group (0.081 ± 0.012 vs 0.063 ± 0.016, respectively; P = .046). DNA content (percentage of wet tissue weight) was also significantly increased in the DFO group compared with the CTL group (0.31 ± 0.05 vs 0.23 ± 0.03, respectively; P = .024). PG content (percentage of wet tissue weight) was significantly decreased in the DFO group compared with the CTL group (0.26 ± 0.02 vs 0.33 ± 0.08, respectively; P = .035). Total chondroid area (number of vessels per mm2 of tissue area evaluated) was significantly decreased in the DFO group compared with the CTL group (17.2 ± 6.6 vs 24.6 ± 5.1, respectively; P = .038). Articular zone vessel density (vessels/mm2) was significantly increased in the DFO group compared with the CTL group (7.1 ± 2.5 vs 2.1 ± 0.9, respectively; P = .026). CONCLUSION: The significant increase in hemoglobin content as well as articular zone vessel density in the DFO group compared with the CTL group is evidence of increased angiogenesis in the fibrocartilaginous region of the tendon exposed to DFO. The DFO group also displayed a significantly greater level of DNA and significantly lower level of PG, suggesting enhanced early healing by fibrous tissue formation. CLINICAL RELEVANCE: Stimulating angiogenesis by DFO-saturated suture may be clinically useful to improve healing of poorly vascularized tissues.