A Survey of Musculoskeletal Disorders in the Orthopaedic Surgeon: Identifying Injuries, Exacerbating Workplace Factors, and Treatment Patterns in the Orthopaedic Community.

INTRODUCTION: As demand for orthopaedic care increases, the orthopaedic community must preserve access to skilled physicians. Workplace hazards and related injuries or conditions contribute to musculoskeletal (MSK) stress on orthopaedic surgeons, which can lead to undesirable medical leaves of absence or early retirement. The purpose of this study was to identify and characterize work-related and non-work-related MSK conditions that affect orthopaedic surgeons and differential injury patterns among male and female surgeons. This study hypothesized that MSK conditions would be exacerbated by work, correlate with age, and show gender-based disparities. Identifying MSK conditions and associated workplace hazards may ultimately help guide preventive or protective efforts. METHODS: Following IRB and society approvals, a modified 15-question physical discomfort survey was emailed to a randomized selection of American Academy of Orthopaedic Surgeons (AAOS) members and all Ruth Jackson Orthopaedic Society members. Data were deidentified and merged by AAOS; analyses were performed by the authors. RESULTS: Most surgeons reported at least one MSK condition (86%; 95% male versus 82% female, P = 0.317), with an average of two conditions per surgeon. Low back pain (56%) and neck pain (42%) were the two most common conditions reported. Male surgeons were more likely to report medial epicondylitis (P = 0.040), lateral epicondylitis (P ≤ 0.001), low back pain (P = 0.001), and lumbar radiculopathy (P = 0.001); however, male respondents were significantly older than female respondents (57 versus 43 years, P ≤ 0.0001), and some conditions were age-correlated. Most respondents reported at least one work-attributed MSK condition (64%; 68% male versus 62% female, P = 0.806). Caseload was not associated with an increased number of work-related MSK conditions; yet, 60% of surgeons reported that work worsened symptoms. Surgical treatment was sought most often for lumbar radiculopathy (6%) and carpal tunnel syndrome (6%). Sixty-nine leaves of absence were reported; most less than 1 month (55%). Exacerbating workplace factors included positioning (patient/surgeon), instruments, and personal protective equipment. DISCUSSION: Work-related MSK conditions are common among orthopaedic surgeons. Greater awareness of potential workplace-related hazards and conditions is needed to address and mitigate negative MSK health effects on orthopaedic surgeons.

Metabolomic Profiling in the Characterization of Degenerative Bone and Joint Diseases.

Osteoarthritis and inflammatory arthropathies are a cause of significant morbidity globally. New research elucidating the metabolic derangements associated with a variety of bone and joint disorders implicates various local and systemic metabolites, which further elucidate the underlying molecular mechanisms associated with these destructive disease processes. In osteoarthritis, atty acid metabolism has been implicated in disease development, both locally and systemically. Several series of rheumatoid arthritis patients have demonstrated overlapping trends related to histidine and glyceric acid, while other series showed similar results of increased cholesterol and glutamic acid. Studies comparing osteoarthritis and rheumatoid arthritis reported elevated gluconic acid and glycolytic- and tricarboxylic acid-related substrates in patients with osteoarthritis, while lysosphingolipids and cardiolipins were elevated only in patients with rheumatoid arthritis. Other bone and joint disorders, including osteonecrosis, intervertebral disc degeneration, and osteoporosis, also showed significant alterations in metabolic processes. The identification of the molecular mechanisms of osteoarthritis and inflammatory arthropathies via metabolomics-based workflows may allow for the development of new therapeutic targets to improve the quality of life in these patient populations.

Surgical Management of Triquetral Osteoid Osteoma with Adjunct Tetracycline for Intraoperative Visualization: A Case Report.

CASE: We report the case of a 15-year-old male patient presenting with persistent wrist pain after surgical treatment of a triquetral osteoid osteoma. The patient was found to have a persistent nidus. These tumors are difficult to observe intraoperatively or through fluoroscopy, limiting adequate resection and resulting in continued pain. CONCLUSION: The nidus was excised successfully through an unusual technique using tetracycline for intraoperative identification. The patient remains asymptomatic without recurrence at 31 months postoperative. Difficulties visualizing and removing carpal lesions leading to recurrence are described.

Femoral nerve block at time of ACL reconstruction causes lasting quadriceps strength deficits and may increase short-term risk of re-injury.

PURPOSE: To determine whether femoral nerve blockade (FNB) at the time of primary ACL reconstruction is associated with meeting isokinetic extension strength return to sport criteria near completion of physical therapy and whether FNB affects 1-year or 2-year risk of ipsilateral ACL graft rupture or contralateral native ACL injury. METHODS: Three-hundred and sixty patients (n = 244 with FNB, n = 116 no FNB) underwent primary ACL reconstruction. All patients completed rehabilitation and underwent functional strength testing towards the end of knee rehabilitation (mean 5.6 months post-surgery). Association between FNB and isokinetic extension strength limb symmetry index (LSI) (goal LSI ≥ 90% for return to sport) as well as risk of recurrent ACL injury within first or second year after surgery was evaluated. RESULTS: Ipsilateral or contralateral ACL injury within 2 years occurred in 11.2% of patients with FNB and 5.7% without FNB (p = 0.01). Patients with FNB had higher incidence of ipsilateral graft rupture within the first year after surgery but no difference in graft rupture during the second. Two-year risk of contralateral ACL injury was similar in both groups. At the time of initial testing, patients who received FNB had lower fast isokinetic extension LSI versus patients without FNB and were less likely achieve a goal ≥ 90% LSI; slow extension LSI was unaffected. CONCLUSION: Use of FNB at the time of primary ACL reconstruction can negatively affect achievement of isokinetic extension strength return to sport criteria. FNB increases risk of graft rupture within the first year after surgery but does not affect re-injury risk during the second. FNB may not be appropriate for use in patients already at high risk of ACL re-injury. LEVEL OF EVIDENCE: III.

Cartilage damage at the time of anterior cruciate ligament reconstruction is associated with weaker quadriceps function and lower risk of future ACL injury.

PURPOSE: To determine whether articular cartilage damage noted at the time of primary anterior cruciate ligament reconstruction (ACLR) affects the likelihood of achieving ≥ 90% symmetry for isokinetic extension strength at 6 months after surgery or risk of recurrent ACL injury. METHODS: Five hundred and eight patients underwent primary ACLR and diagnostic arthroscopy. All identified cartilage lesions were graded using the Outerbridge system. All patients underwent isokinetic strength testing. The association between cartilage Outerbridge grade and a ≥ 90% Limb Symmetry Index (LSI) and recurrent ACL injury risk at mean 38.7 month follow-up (SD 31.8) was evaluated via multivariate regression analysis. RESULTS: Grade 2 or higher damage was present in 394 (77.5%) of patients, grade 3 or higher in 143 (28.1%) and grade 4 in 83 (16.4%) at time of ACLR. Ipsilateral ACLR graft rupture occurred in 31 (6.1%) of patients. Contralateral ACL injury occurred in 19 (3.7%). Patients with grade 2 or higher damage were significantly less likely to meet an LSI goal of ≥ 90% for fast (300°/s) isokinetic extension. There was no association with slow isokinetic extension. Cartilage lesion severity at or beyond grade 2 had a similar effect on isokinetic testing results regardless of compartment involvement or performance of microfracture. Patients with grade 2-4 cartilage damage were less likely to sustain a second ipsilateral ACL injury or a contralateral native ACL injury. CONCLUSIONS: Cartilage damage seen at time of ACL reconstruction is common and associated with lower likelihood of achieving ≥ 90% symmetry for isokinetic extension strength at 6 months after surgery. However, lower recurrent ACL injury rates are seen in patients with concurrent cartilage damage. These data may inform future clinical decisions regarding operative managment of recurrent ACL injuries. LEVEL OF EVIDENCE: III.

Anterior cruciate ligament reconstruction complicated by Propionibacterium acnes infection: case series.

Anterior cruciate ligament (ACL) reconstruction is one of the most commonly performed orthopaedic procedures. While generally successful, failure resulting in revision surgery is reported to be between 1.9 - 4.9%. However, when not related to traumatic re-injury, failure mechanism is poorly understood. One potential but understudied mechanism of ACL reconstruction failure is infection. We describe three patients with previous ACL reconstructions who later developed infection with Propionibacterium acnes. Two cases presented with knee pain and swelling, and one presented with instability. While only two of the three cases received antibiotic treatment, all three cases were free of knee and infectious symptomatology at most recent follow-up. P. acnes infection may represent one potential mechanism for biologic failure of ACL reconstruction and anaerobic operative cultures may be used to identify its presence.

The Effect of Femoral Nerve Block on Quadriceps Strength in Anterior Cruciate Ligament Reconstruction: A Systematic Review.

PURPOSE: To assess the isokinetic, functional, and patient-reported outcomes of femoral nerve block (FNB) compared with traditional multimodal anesthesia for FNB in anterior cruciate ligament (ACL) reconstruction. METHODS: A systematic search of PubMed, Scopus, Cumulative Index to Nursing and Allied Health Literature, Cochrane Reviews, and Google Scholar was conducted according to the 2009 Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Effects of FNB on quadriceps function were evaluated by isokinetic testing, functional scoring systems, range of motion, and patient self-report questionnaires. Heterogeneous reporting of outcomes precluded a formal meta-analysis. The methodologic merit of all studies included was evaluated by the Coleman Methodology Score. RESULTS: Six studies were identified with outcome measures reported between 7 days and 6 months postoperatively. At 6 months, 2 of 4 studies that reported isokinetic testing found significantly greater deficits among patients who received a nerve block; one of the remaining studies showed a deficit at 6 weeks but not 6 months. Limited data showed no significant differences in functional or patient-reported outcomes at 6 months after reconstruction, and data regarding the impact of FNB on return to sport were inconclusive. The mean Coleman Methodology Score for the included studies was 53, indicating poor overall methodologic quality of the available literature. CONCLUSIONS: The limited data available suggest that FNB causes a measurable deficit in quadriceps isokinetic strength during the early postoperative period but has no effect on functional outcomes or return to sport at 6 months after ACL reconstruction. However, current clinical evidence is not sufficient to draw any valid or definitive conclusions regarding the effect of FNB on postoperative outcomes after ACL reconstruction. LEVEL OF EVIDENCE: Level IV, systemic review of Level I through IV studies.

The effect of donor age on structural and mechanical properties of allograft tendons.

BACKGROUND: Allograft tendons are commonly used in surgical ligament reconstruction. While it is commonly accepted that donor age will affect mechanical properties of graft tissue, the apparent age threshold is unknown. HYPOTHESIS: Donor age will significantly influence the structural and mechanical properties of tibialis posterior allograft tendons. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 550 allograft posterior tibialis tendons were examined. Linear stiffness, ultimate tensile force, ultimate displacement, tensile modulus, ultimate tensile strength, and ultimate tensile strain were calculated for specimens from donors in each of 6 age groups: 15-29, 30-39, 40-49, 50-59, 60-69, and 70-79 years. Both first- and second-order polynomial regressions were performed to determine the correlation between structural and mechanical properties and age. Welch analyses of variance with Games-Howell post hoc tests were performed to facilitate comparisons among age groups. RESULTS: All parameters displayed a weak correlation with age, with the highest R (2) term being 0.063 for ultimate tensile strength. Linear stiffness, ultimate tensile force, and tensile modulus displayed almost no correlation with age. Ultimate tensile strength increased slightly with age up to 40-49 years and then decreased with further increases in age. Slight decreases in ultimate displacement and ultimate tensile strain were observed with increasing age. Numerous statistically significant differences were observed between age groups for each outcome parameter; however, the magnitudes of the differences between age groups are relatively small (<15%) for all outcome parameters. CONCLUSION: Age explained at most 6% of the variation in structural and mechanical properties of tibialis posterior allograft tendons. CLINICAL RELEVANCE: Posterior tibialis tendons from all age groups displayed structural properties superior to the native anterior cruciate ligament, with higher stiffness and ultimate force, and less displacement to failure. Although statistically significant differences in structural and mechanical properties were observed between age groups, the magnitudes of the differences are small and most likely not clinically relevant. The age of the donor will not likely affect the suitability of a graft for use in surgical reconstruction.

Toll-like receptors-2 and 4 are overexpressed in an experimental model of particle-induced osteolysis.

Aseptic loosening secondary to particle-associated periprosthetic osteolysis remains a major cause of failure of total joint replacements (TJR) in the mid- and long term. As sentinels of the innate immune system, macrophages are central to the recognition and initiation of the inflammatory cascade, which results in the activation of bone resorbing osteoclasts. Toll-like receptors (TLRs) are involved in the recognition of pathogen-associated molecular patterns and danger-associated molecular patterns. Experimentally, polymethylmethacrylate and polyethylene (PE) particles have been shown to activate macrophages via the TLR pathway. The specific TLRs involved in PE particle-induced osteolysis remain largely unknown. We hypothesized that TLR-2, -4, and -9 mediated responses play a critical role in the development of PE wear particle-induced osteolysis in the murine calvarium model. To test this hypothesis, we first demonstrated that PE particles caused observable osteolysis, visible by microCT and bone histomorphometry when the particles were applied to the calvarium of C57BL/6 mice. The number of TRAP positive osteoclasts was significantly greater in the PE-treated group when compared to the control group without particles. Finally, using immunohistochemistry, TLR-2 and TLR-4 were highly expressed in PE particle-induced osteolytic lesions, whereas TLR-9 was downregulated. TLR-2 and -4 may represent novel therapeutic targets for prevention of wear particle-induced osteolysis and accompanying TJR failure.