This analysis confirms previously demonstrated risk factors for postoperative infection while reporting on new potential independent risk factors of osteoporosis, chronic obstructive pulmonary disease, and dural tears in the setting of posterior lumbar instrumented arthrodesis. Areas of new research can focus on the roles these novel factors may play in the pathogenesis of surgical site infections in the spine.

Participants who received intradiskal PRP showed significant improvements in FRI, NRS Best Pain, and NASS patient satisfaction scores over 8 weeks compared with controls. Those who received PRP maintained significant improvements in FRI scores through at least 1 year of follow-up. Although these results are promising, further studies are needed to define the subset of participants most likely to respond to biologic intradiskal treatment and the ideal cellular characteristics of the intradiskal PRP injectate.

Reduction of bone turnover with bisphosphonate treatment alters bone mineral and matrix properties. Our objective was to investigate the effect of bisphosphonate treatment on bone tissue properties near fragility fracture sites in the proximal femur in postmenopausal women with osteoporosis. The mineral and collagen properties of cortico-cancellous biopsies from the proximal femur were compared in bisphosphonate-naive (-BIS, n=20) and bisphosphonate-treated (+BIS, n=20, duration 7 ± 5 y) patients with intertrochanteric (IT) and subtrochanteric (ST) fractures using Fourier transform infrared imaging (FTIRI). The mean values of the FTIRI parameter distributions were similar across groups, but the widths of the parameter distributions tended to be reduced in the +BIS group relative to the -BIS group. Specifically, the distribution widths of the cortical collagen maturity and crystallinity were reduced in the +BIS group relative to those of the -BIS group by 28% (+BIS 0.45 ± 0.18 vs. -BIS 0.63 ± 0.28, p=0.03) and 17% (+BIS 0.087 ± 0.012 vs. -BIS 0.104 ± 0.036, p=0.05), respectively. When the tissue properties were examined as a function of fracture morphology within the +BIS group, the FTIR parameters were generally similar regardless of fracture morphology. However, the cortical mineral:matrix ratio was 8% greater in tissue from patients with atypical ST fractures (n =6) than that of patients with typical (IT or spiral ST) fractures (n=14) (Atypical 5.6 ± 0.3 vs. Typical 5.2 ± 0.5, p=0.03). Thus, although the mean values of the FTIR properties were similar in both groups, the tissue in bisphosphonate-treated patients had a more uniform composition than that of bisphosphonate-naïve patients. The observed reductions in mineral and matrix heterogeneity may diminish tissue-level toughening mechanisms.

The prevalence of low serum levels of vitamin D among patients undergoing orthopaedic surgery is very common. Given the importance of vitamin D in musculoskeletal health, such low levels may negatively impact patient outcomes.

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