Exploring relationships among multi-disciplinary assessments for knee joint health in service members with traumatic unilateral lower limb loss: a two-year longitudinal investigation.

Motivated by the complex and multifactorial etiologies of osteoarthritis, here we use a comprehensive approach evaluating knee joint health after unilateral lower limb loss. Thirty-eight male Service members with traumatic, unilateral lower limb loss (mean age = 38 yr) participated in a prospective, two-year longitudinal study comprehensively evaluating contralateral knee joint health (i.e., clinical imaging, gait biomechanics, physiological biomarkers, and patient-reported outcomes); seventeen subsequently returned for a two-year follow-up visit. For this subset with baseline and follow-up data, outcomes were compared between timepoints, and associations evaluated between values at baseline with two-year changes in tri-compartmental joint space. Upon follow-up, knee joint health worsened, particularly among seven Service members who presented at baseline with no joint degeneration (KL = 0) but returned with evidence of degeneration (KL ≥ 1). Joint space narrowing was associated with greater patellar tilt (r[12] = 0.71, p = 0.01), external knee adduction moment (r[13] = 0.64, p = 0.02), knee adduction moment impulse (r[13] = 0.61, p = 0.03), and CTX-1 concentration (r[11] = 0.83, p = 0.001), as well as lesser KOOSSport and VR-36General Health (r[16] = - 0.69, p = 0.01 and r[16] = - 0.69, p = 0.01, respectively). This longitudinal, multi-disciplinary investigation highlights the importance of a comprehensive approach to evaluate the fast-progressing onset of knee osteoarthritis, particularly among relatively young Service members with lower limb loss.

Active Duty Service Members Newly Presenting With Low Back Pain in Fiscal Year 2017: Health Care Utilization, Access to Care, and Private Sector Costs Over 2-year Follow-up.

INTRODUCTION: Low back pain (LBP) has accounted for the most medical encounters every year for the past decade among Active Duty Service Members (ADSMs) of the U.S. Armed Forces. The objectives of this retrospective, descriptive study were to classify LBP by clinical category (Axial, Radicular, and Other) and duration (Acute, Subacute, and Chronic) and examine the LBP-related health care utilization, access to care, and private sector costs for ADSMs over a 2-year follow-up period. MATERIALS AND METHODS: The Military Health System Data Repository was queried in fiscal year 2017 for all ADSMs (ages 18-62) with outpatient encounters documented with any of 67 ICD-10 diagnosis codes indicative of LBP. A 1-year clean period before the first (index) outpatient LBP encounter date was used to ensure no recent history of LBP care. Patients were eligible if continuously enrolled and on active duty for 1 year before and 2 years following the index visit. Patients were excluded for non-musculoskeletal causes for LBP, red flags, or acute trauma within 4 weeks of the index visit and/or systemic illness or pregnancy anytime during the clean or follow-up period. RESULTS: A total of 52,118 ADSMs met the inclusion criteria, and the cohort was classified by duration of LBP symptoms as Acute [17,916 (34.4%)], Subacute [4,119 (7.9%)], and Chronic [30,083 (57.7%)]. Over 2-year follow-up, 419,983 outpatient visits were recorded, with the majority occurring at MTFs [363,570 (86.6%)]. 13,237 (25.4%) of ADSMs in the total cohort were documented with no other LBP-related visits beyond their index encounter. In contrast, the Chronic cohort comprised the highest number of encounters [371,031 (89.2% of total encounters)], including 86% of imaging studies performed for LBP, and accounted for $9,986,606.17 (94.9%) of total private sector costs over the 2-year follow-up period. Interventional pain procedures ($2,983,767.50) and physical therapy ($2,298,779.07) represented the costliest categories in the private sector for the Chronic cohort, whereas Emergency Department ($283,307.43) and physical therapy ($137,035.54) encounters were the top contributors to private sector costs for the Acute and Subacute cohorts, respectively. Overall reliance on the private sector was highest for specialty care, including 10,721 (75.4%) interventional pain procedures and 306 (66.4%) spine surgeries. CONCLUSIONS: Uncovering current trends in health care utilization and access to care for ADSMs newly presenting with LBP is vital for timely and accurate diagnosis, as well as early intervention to prevent progression to chronic LBP and to minimize its negative impact on military readiness and quality of life. This retrospective, descriptive study highlights the burden of chronic LBP on health care utilization and costs within the Military Health System, including reliance on the private sector care, amounting to $10,524,332.04 over the study period.

A Comprehensive, Multidisciplinary Assessment for Knee Osteoarthritis Following Traumatic Unilateral Lower Limb Loss in Service Members.

INTRODUCTION: Knee osteoarthritis (KOA) is a primary source of long-term disability and decreased quality of life (QoL) in service members (SM) with lower limb loss (LL); however, it remains difficult to preemptively identify and mitigate the progression of KOA and KOA-related symptoms. The objective of this study was to explore a comprehensive cross-sectional evaluation, at the baseline of a prospective study, for characterizing KOA in SM with traumatic LL. MATERIALS AND METHODS: Thirty-eight male SM with traumatic unilateral LL (23 transtibial and 15 transfemoral), 9.5 ± 5.9 years post-injury, were cross-sectionally evaluated at initial enrollment into a prospective, longitudinal study utilizing a comprehensive evaluation to characterize knee joint health, functionality, and QoL in SM with LL. Presences of medial, lateral, and/or patellofemoral articular degeneration within the contralateral knee were identified via magnetic resonance imaging(for medically eligible SM; Kellgren-Lawrence Grade [n = 32]; and Outerbridge classification [OC; n = 22]). Tri-planar trunk and pelvic motions, knee kinetics, along with temporospatial parameters, were quantified via full-body gait evaluation and inverse dynamics. Concentrations of 26 protein biomarkers of osteochondral tissue degradation and inflammatory activity were identified via serum immunoassays. Physical function, knee symptoms, and QoL were collected via several patient reported outcome measures. RESULTS: KOA was identified in 12 of 32 (37.5%; KL ≥ 1) SM with LL; however, 16 of 22 SM presented with patellofemoral degeneration (72.7%; OC ≥ 1). Service members with versus without KOA had a 26% reduction in the narrowest medial tibiofemoral joint space. Biomechanically, SM with versus without KOA walked with a 24% wider stride width and with a negative correlation between peak knee adduction moments and minimal medial tibiofemoral joint space. Physiologically, SM with versus without KOA exhibited elevated concentrations of pro-inflammatory biomarker interleukin-7 (+180%), collagen breakdown markers collagen II cleavage (+44%), and lower concentrations of hyaluronic acid (-73%) and bone resorption biomarker N-telopeptide of Type 1 Collagen (-49%). Lastly, there was a negative correlation between patient-reported contralateral knee pain severity and patient-reported functionality and QoL. CONCLUSIONS: While 37.5% of SM with LL had KOA at the tibiofemoral joint (KL ≥ 1), 72.7% of SM had the presence of patellofemoral degeneration (OC ≥ 1). These findings demonstrate that the patellofemoral joint may be more susceptible to degeneration than the medial tibiofemoral compartment following traumatic LL.