Influence of Staphylococcus epidermidis biofilm on the mechanical strength of soft tissue allograft.

We sought to determine the impact of bacterial inoculation and length of exposure on the mechanical integrity of soft tissue tendon grafts. Cultures of Staphylococcus epidermidis were inoculated on human tibialis posterior cadaveric tendon to grow biofilms. A low inoculum in 10% growth medium was incubated for 30 min to replicate conditions of clinical infection. Growth conditions assessed included inoculum concentrations of 100, 1000, 10,000 colony-forming units (CFUs). Tests using the MTS Bionix system were performed to assess the influence of bacterial biofilms on tendon strength. Load-to-failure testing was performed on the tendons, and the ultimate tensile strength was obtained from the maximal force and the cross-sectional area. Displacements of tendon origin to maximal displacement were normalized to tendon length to obtain strain values. Tendon force-displacement and stress-strain relationships were calculated, and Young's modulus was determined. Elastic modulus and ultimate tensile strength decreased with increasing bioburden. Young's modulus was greater in uninoculated controls compared to tendons inoculated at 10,000 CFU (p = 0.0011) but unaffected by bacterial concentrations of 100 and 1000 CFU (p = 0.054, p = 0.078). Increasing bioburden was associated with decreased peak load to failure (p = 0.043) but was most significant compared to the control under the 10,000 and 1000 CFU growth conditions (p = 0.0005, p = 0.049). The presence of S. epidermidis increased elasticity and decreased ultimate tensile stress of human cadaveric tendons, with increasing effect noted with increasing bioburden.

Patellofemoral articular cartilage damage is associated with poorer patient-reported outcomes following isolated medial patellofemoral ligament reconstruction.

PURPOSE: The purpose of this study was to investigate the impact of articular cartilage damage on outcomes following medial patellofemoral ligament (MPFL) reconstruction. METHODS: Record review identified 160 patients who underwent isolated MPFL reconstruction at a single institution between 2008 and 2016. Patient demographics, patellofemoral articular cartilage status at surgery, and patient anatomical measures from imaging were obtained via chart review. Patients were contacted and outcomes assessed through collection of Norwich Patellar Instability (NPI) score, Knee injury and Osteoarthritis Outcome Score (KOOS), and Marx activity score as well as an assessment for recurrent patellar dislocation. Outcomes of patients with grade 0-II patellofemoral cartilage damage were compared to those of patients with grade III-IV cartilage damage. RESULTS: One hundred twenty-two patients (76%) with a minimum of one year follow-up were contacted at a mean of 4.8 years post-operatively. A total of 63 patients (52%) had grade III or IV patellofemoral chondral damage at the time of surgery. The majority of the defects was on the medial patella (46 patients-72%) and the mean patellar defect size was 2.8 cm2. Among 93 patients who completed patient-reported outcome scores, the 52 with grade III or IV chondral damage reported a significantly poorer KOOS Quality of Life than the 44 patients with grade 0 to II chondral damage (p = 0.041), controlling for patient age, sex, BMI, and anatomical factors. CONCLUSION: Patients with grade III or IV articular cartilage damage of the patellofemoral joint at the time of MPFL reconstruction demonstrated poorer KOOS knee-related quality of life than patients without grade III or IV articular cartilage damage at a mean of 4.8 years following isolated MPFL reconstruction. LEVEL OF EVIDENCE: Level II.

The quality and accuracy of direct-to-consumer biologic marketing for shoulder pathology are poor.

Background: The growing role of biologic therapies as adjunct or standalone procedures in orthopedic practice has led to greater levels of direct-to-consumer biologic marketing. The present study aims to assess the quality, accuracy, and readability of online educational resources available to patients regarding biologic therapies for shoulder pathology. Methods: Eight search terms relevant to shoulder biologic therapies (shoulder + BMAC, Bone Marrow Aspirate Concentrate, PRP, Platelet Rich Plasma, Lipogems, Adipose Tissue, Biologic therapy, and Stem cell therapy) were searched across three separate search engines. The first 25 websites of each search were recorded. Duplicate websites and those not specific to shoulder pathology were excluded. Three evaluators independently assessed quality using an author-derived scoring rubric for a total of 25 possible points and accuracy for a total of 12 possible points. The Flesch-Kincaid readability test was used to quantify reading levels. Websites were further characterized by authorship and the presence of commercial bias. Results: Of the 600 results from the initial search, 59 met inclusion criteria. The mean quality of the websites was poor, with 7.97 ± 2.3 of 25 points (32%). The mean accuracy was low, with 8.47 ± 1.52 of 12 points (71%). The average reading level was 11.2 ± 1.93, with 32% of websites' reading at greater than 12th grade reading level. The search terms of "shoulder PRP" and "shoulder Platelet Rich Plasma" yielded the highest quality results (mean = 8.14 ± 2.63). "shoulder Lipogems" and "shoulder Adipose tissue" yielded the most accurate results (mean = 9.25 ± 0.96). "shoulder BMAC" and "shoulder bone marrow aspirate concentrate" were most difficult to read (mean = 12.54 ± 3.73). Sixty-four percent of websites were authored by physicians, hospitals, or medical groups. The accuracy of websites authored by health care professionals was significantly higher than the accuracy of those authored by other industry sources (P = .01). Fifteen percent of websites demonstrated commercial bias. Discussion: The online resources available to patients seeking information about biologic therapies for the treatment of shoulder pathologies are of very poor quality, moderately poor accuracy, and advanced readability. Providers should caution patients about the reliability of direct-to-consumer biologic marketing for shoulder pathology. Conclusion: The information available to patients online regarding the diagnosis, evaluation, and treatment of shoulder pathology with biologic therapies is of poor quality and accuracy and difficult readability.