Browsing by Subject "Tendon"

Now showing 1 - 6 of 6
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    Accuracy of MRI in Assessment of High-Grade Partial Distal Biceps Tears
    (Sage, 2025) Schmidt, Gregory J.; Fischer, James P.; Hoyer, Reed W.; Greenberg, Jeffrey A.; Crosby, Nicholas E.; Graduate Medical Education, School of Medicine
    Background: Magnetic resonance imaging (MRI) is commonly used to diagnose and assess the extent of partial distal biceps injuries. The aim of this study was to report on the accuracy of MRI and the effect of injury history and study timing on its performance. Methods: A retrospective review of all patients who underwent surgical treatment of partial thickness distal biceps tears at a single center by multiple surgeons was performed. Inclusion criteria consisted of the performance of a preoperative MRI and documentation of the intraoperatively visualized extent of the tear, and 68 patients met the criteria for inclusion. A chart review was completed to evaluate the symptom duration, injury history, and tear extent. Results: All patients had distal biceps tears of greater than 50% intraoperatively. However, MRI did not indicate any tearing in 20 (29%) patients, and its sensitivity for high-grade tear was 44%. Magnetic resonance imaging was significantly less likely to be read as high-grade tears in patients with insidious onset of their symptoms in comparison with patients who reported a traumatic onset (27% vs 55%, P = .024). However, the time from symptom onset to MRI did not significantly correlate with diagnosis of a high-grade tear on MRI (r = -0.15, P = .21). Conclusions: These results indicate that MRI can underreport partial distal biceps tear extent, and this more commonly occurs in patients with insidious onset of pain.
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    Age-related changes in structure and extracellular matrix protein expression levels in rat tendons
    (Springer, Part of Springer Science+Business Media, 2013-12) Kostrominova, Tatiana Y.; Brooks, Susan V.; Department of Anatomy & Cell Biology, School of Medicine
    The musculoskeletal system (muscle–tendon–bone) demonstrates numerous age-related changes, with modifications in tendons the least well studied, although increased predisposition to tendinopathy and rupture have been reported. In order to gain insights into the basis of age-associated increase in tendon injuries, we compared Achilles and tibialis anterior tendons and myotendinous junctions (MTJs) from 3- to 5- and 22- to 25-month-old rats for underlying structure and composition. Significant decreases were observed by qRT-PCR for collagen I, III, and V mRNA expression in tendons of old rats, but immunostaining detected no apparent differences in collagen I and V expression on the protein level. Tendons of old compared with young rats had decreased mRNA expression levels of proteoglycan 4 (PRG4) and elastin (Eln), but no differences in the mRNA expression of connective tissue growth factor, TGF-beta 1, or stromal cell-derived factor 1. For PRG4, immunostaining showed good correlation with qRT-PCR results. This is the first study to show reductions in PRG4 in tendons and MTJs of old rats. Decreased PRG4 expression in tendons could result in increased tendon stiffness and may be associated with decreased activity in the elderly. The diminished collagen mRNA expression in combination with decreased PRG4 and Eln mRNA expression may be associated with increased risk of tendon injury with aging.
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    Barriers to Upper Extremity Reconstruction for Patients With Cerebral Palsy
    (Sage, 2022) Loewenstein, Scott N.; Angulo-Parker, Francisco; Timsina, Lava; Adkinson, Joshua; Surgery, School of Medicine
    Background: Reconstructive surgery for upper extremity manifestations of cerebral palsy (CP) has been demonstrated to be safe and effective, yet many potential candidates are never evaluated for surgery. The purpose of this study was to determine barriers to upper extremity reconstruction for patients with CP in a cohort of upper extremity surgeons and nonsurgeons. Methods: We sent a questionnaire to 4167 surgeons and nonsurgeon physicians, aggregated responses, and analyzed for differences in perceptions regarding surgical efficacy, patient candidacy for surgery, compliance with rehabilitation, remuneration, complexity of care, and physician comfort providing care. Results: Surgeons and nonsurgeons did not agree on the literature support of surgical efficacy (73% vs 35% agree or strongly agree, respectively). Both surgeons and nonsurgeons felt that many potential candidates exist, yet there was variability in their confidence in identifying them. Most surgeons (59%) and nonsurgeons (61%) felt comfortable performing surgery and directing the associated rehabilitation, respectively. Neither group reported that patient compliance, access to rehabilitation services, and available financial resources were a major barrier, but surgeons were more likely than nonsurgeons to feel that remuneration for services was inadequate (37% vs 13%). Both groups agreed that surgical treatments are complex and should be performed in the setting of a multidisciplinary team. Conclusions: Surgeons and nonsurgeons differ in their views regarding upper extremity reconstructive surgery for CP. Barriers to reconstruction may be addressed by performing higher level research, implementing multispecialty educational outreach, developing objective referral criteria, increasing surgical remuneration, improving access to trained upper extremity surgeons, and implementing multidisciplinary CP clinics.
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    Connexins and pannexins in the skeleton: gap junctions, hemichannels and more
    (Springer, 2015-08) Plotkin, Lilian I.; Stains, Joseph P.; Department of Anatomy & Cell Biology, IU School of Medicine
    Regulation of bone homeostasis depends on the concerted actions of bone-forming osteoblasts and bone-resorbing osteoclasts, controlled by osteocytes, cells derived from osteoblasts surrounded by bone matrix. The control of differentiation, viability and function of bone cells relies on the presence of connexins. Connexin43 regulates the expression of genes required for osteoblast and osteoclast differentiation directly or by changing the levels of osteocytic genes, and connexin45 may oppose connexin43 actions in osteoblastic cells. Connexin37 is required for osteoclast differentiation and its deletion results in increased bone mass. Less is known on the role of connexins in cartilage, ligaments and tendons. Connexin43, connexin45, connexin32, connexin46 and connexin29 are expressed in chondrocytes, while connexin43 and connexin32 are expressed in ligaments and tendons. Similarly, although the expression of pannexin1, pannexin2 and pannexin3 has been demonstrated in bone and cartilage cells, their function in these tissues is not fully understood.
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    Primary Repair of Chronic Distal Biceps Tendon Tears
    (Sage, 2024) Schmidt, Gregory J.; Dmochowski, Jakub M.; Gudeman, Andrew S.; Cage, Emily S.; Greenberg, Jeffrey A.; Hoyer, Reed W.; Graduate Medical Education, School of Medicine
    Background: This study reports the clinical results following primary repair of distal biceps tendon ruptures more 6 weeks after injury. Methods: A retrospective review of distal biceps tendon repairs performed by 8 different hand surgeons from January 1, 2015 to October 15, 2020 was performed. Patients with complete tears surgically treated ≥6 weeks after injury without tendon graft were included. Thirty patients qualified and underwent chart review for complication and range of motion (ROM) data. They were contacted for final patient-reported outcome measures (PROMs) using Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) and Patient Reported Elbow Evaluation (PREE) scores. Final PROMs were obtained from 21 patients with an average follow-up of 31.3 months (range: 4-71 months). Results: Average time from injury to repair was 71 days (range: 42-204). The average QuickDASH score was 6.6 (±6.2) and PREE score was 7.8 (±8.0). The amount of elbow flexion necessary to complete the repair was documented in 21 patients and averaged 64º (±10º). Postoperatively, patients achieved an average extension/flexion of 1º (±1º) to 138º (±2º) and pronation/supination of 76º (±4º) to 77º (±3º). Complications were reported in 14 patients (47%) and included 2 re-ruptures, 1 adhesive scar formation, 1 superficial infection, 1 intraoperative lateral antebrachial cutaneous nerve laceration, 12 neuropraxias, and 1 case of heterotopic ossification (HO). Conclusions: Primary repair of chronic distal biceps tendon tears greater than 6 weeks from injury demonstrated excellent PROMs and elbow ROM. However, the complication rate may be higher than early repair.
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    Use of an Abductor Pollicis Brevis Tendon Slip for Reconstruction of the Radial Collateral Ligament of the Thumb Metacarpophalangeal Joint: An Anatomical Investigation
    (Sage, 2023) Schmidt, Gregory J.; Crosby, Nicholas E.; Merrell, Gregory A.; Graduate Medical Education, School of Medicine
    Background: Reconstruction of the radial collateral ligament (RCL) of the thumb metacarpophalangeal (MP) joint is commonly performed for chronic injuries. This study aims to evaluate the anatomical feasibility and reliability of using the abductor pollicis brevis (APB) tendon to reconstruct the RCL. Methods: Ten cadaver arms were dissected to evaluate the relationship between insertions of the RCL and APB. A slip of the APB was divided from tendon and reflected proximally. The dissected tendon was deemed sufficient for reconstruction if it could be reflected to the footprint of the RCL origin. The size of the dissected APB slip was then compared with that of the RCL. Results: The dissected slip of the APB could be fully reflected proximally to the RCL origin in all specimens. The APB insertion was also found to be closely approximated to the RCL insertion, averaging 2.1 mm distal and 1.8 mm dorsal. Significant differences existed between the lengths (P < .001) of the APB slip and RCL, with no significant difference in widths (P = .051). Conclusions: A sufficient APB tendon slip can be obtained to reliably reconstruct the RCL of the thumb MP. The location of the APB insertion closely approximates the RCL insertion.