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Lan Chen, M.D.

Lan Chen, M.D.

Lan Chen, M.D.

Foot & Ankle Surgery, Bunions, Sports & Dance Related Foot & Ankle Injuries
  • Locations

    NorthShore Medical Group

    9650 Gross Point Rd.
    Suite 2900
    Skokie, IL 60076
    847.866.7846 224.251.2905 fax Get Directions This location is wheelchair accessible.

    NorthShore Medical Group

    2180 Pfingsten Rd.
    Suite 3100
    Glenview, IL 60026
    847.866.7846 866.954.5787 fax Get Directions This location is wheelchair accessible.
  • Publications
    • Effect of diabetes mellitus on perioperative complications and hospital outcomes after ankle arthrodesis and total ankle arthroplasty.

      Foot & ankle international 2015 Mar

      Authors: Schipper ON, Jiang JJ, Chen L, Koh J, Toolan BC
      The aim of this investigation was to analyze a nationally representative admissions database to evaluate the effect of diabetes mellitus on the rate of perioperative complications and hospitalization outcomes after ankle arthrodesis (AAD) and total ankle arthroplasty (TAA).
      Using the Nationwide Inpatient Sample database, 12 122 patients who underwent AAD and 2973 patients who underwent TAA were identified from 2002 to 2011 based on ICD-9 procedure codes. The perioperative complications and hospitalization outcomes were compared between diabetic and nondiabetic patients for each surgery during the index hospital stay.
      The overall complication rate in the AAD group was 16.4% in diabetic patients and 7.0% in nondiabetic patients (P < .001). Multivariate analysis demonstrated that diabetes mellitus was independently associated with an increased risk of myocardial infarction (relative risk [RR] = 3.2, P = .008), urinary tract infection (RR = 4.6, P < .001), blood transfusion (RR = 3.0, P < .001), irrigation and debridement (RR = 1.9, P = .001), and overall complication rate (RR = 2.7, P < .001). Diabetes was also independently associated with a statistically significant increase in length of hospital stay (difference = 0.35 days, P < .001), more frequent nonhome discharge (RR = 1.69, P < .001), and higher hospitalization charges (difference = $1908, P = .04). The overall complication rate in the TAA group was 7.8% in diabetic patients and 4.7% in nondiabetic patients. Multivariate analysis demonstrated that diabetes was independently associated with increased risk of blood transfusion (RR = 9.8, P = .03) and overall complication rate (RR = 4.1, P = .02). Diabetes was also independently associated with a statistically significant increase in length of stay (difference = 0.41 days, P < .001) and more frequent nonhome discharge (RR = 1.88, P < .001), but there was no significant difference in hospitalization charges (P = .64).
      After both AAD and TAA, diabetes mellitus was independently associated with a significantly increased risk of perioperative complications, nonhome discharge, and length of hospital stay during the index hospitalization.
      PMID: 25413307 [PubMed - as supplied by publisher]
    • Validation of the Foot and Ankle Outcome Score in adult acquired flatfoot deformity.

      Foot & ankle international 2013 Aug

      Authors: Mani SB, Brown HC, Nair P, Chen L, Do HT, Lyman S, Deland JT, Ellis SJ
      The American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score has been under recent scrutiny. The Foot and Ankle Outcome Score (FAOS) is an alternative subjective survey, assessing outcomes in 5 subscales. It is validated for lateral ankle instability and hallux valgus patients. The aim of our study was to validate the FAOS for assessing outcomes in flexible adult acquired flatfoot deformity (AAFD).
      Patients from the authors' institution diagnosed with flexible AAFD from 2006 to 2011 were eligible for the study. In all, 126 patients who completed the FAOS and the Short-Form 12 (SF-12) on the same visit were included in the construct validity component. Correlation was deemed moderate if the Spearman's correlation coefficient was .4 to .7. Content validity was assessed in 63 patients by a questionnaire that asked patients to rate the relevance of each FAOS question, with a score of 2 or greater considered acceptable. Reliability was measured using intraclass correlation coefficients (ICCs) in 41 patients who completed a second FAOS survey. In 49 patients, preoperative and postoperative FAOS scores were compared to determine responsiveness.
      All of the FAOS subscales demonstrated moderate correlation with 2 physical health related SF-12 domains. Mental health related domains showed poor correlation. Content validity was high for the Quality of Life (QoL; mean 2.26) and Sports/Recreation subscales (mean 2.12). All subscales exhibited very good test-retest reliability, with ICCs of .7 and above. Symptoms, QoL, pain, and daily activities (ADLs) were responsive to change in postoperative patients (P < .05).
      This study has validated the FAOS for AAFD with acceptable construct and content validity, reliability, and responsiveness. Given its previous validation for patients with ankle instability and hallux valgus, the additional findings in this study support its use as an alternative to less reliable outcome surveys.
      Level II, prospective comparative study.
      PMID: 23513031 [PubMed - as supplied by publisher]
    • Validation of foot and ankle outcome score for hallux valgus.

      Foot & ankle international 2012 Dec

      Authors: Chen L, Lyman S, Do H, Karlsson J, Adam SP, Young E, Deland JT, Ellis SJ
      Patient-reported outcome questionnaires such as the Foot and Ankle Outcome Score (FAOS) are useful in evaluating results after orthopedic interventions. However, despite being frequently used in the literature, its validity has not been established for forefoot disorders. Our study aimed to validate the FAOS for use in assessing outcomes of hallux valgus surgery.
      From 2006 to 2009, 195 patients with nonarthritic hallux valgus were included in the construct validity portion of the study. Patients had a SF-36 and a FAOS completed. Forty additional patients, both preoperative and postoperative, were given questionnaires to assess the relevance of each of the FAOS questions as it pertained to their bunions. Patients were also given the FAOS 1 month after the first to assess FAOS reliability. Responsiveness of the FAOS was included with 40 patients who had both preoperative and postoperative FAOS scores.
      Four out of five FAOS subscales demonstrated acceptable correlation with the SF-36. The FAOS symptoms subscale showed the least correlation with SF-36, demonstrating the foot-specific nature of the questions. Both preoperative and postoperative patients rated the FAOS quality of life questions as the most relevant. All five subscales achieved acceptable test-retest reliability. The FAOS sports and recreation subscale was the least responsive.
      Patient-based assessments have become increasingly important in evaluating treatment effectiveness. This study has shown that the FAOS has acceptable construct validity, reliability, and responsiveness in hallux valgus patients and is a useful patient-based tool in assessing these patients.
      PMID: 23199868 [PubMed - as supplied by publisher]
    • Achilles lengthening procedures.

      Foot and ankle clinics 2009 Dec

      Authors: Chen L, Greisberg J
      Contracture of the gastrocnemius-soleus complex with equinus deformity is a common hindfoot condition. In children, it is frequently associated with neuromuscular conditions such as cerebral palsy. In the adult population, it is linked to numerous pathologies such as adult-acquired flatfoot, diabetic neuropathic ulcers, and plantar fasciitis. With the medial column reduced, failure to achieve 10 degrees of passive ankle dorsiflexion with the knee flexed and extended suggests a contracture. This article reviews the anatomical and evolutionary basis for human foot structure, implications of tight gastrocnemius, and specific disease states. Operative releases for lengthening, including proximal gastrocnemius recession, tendo-Achilles lengthening, and endoscopic recession, are detailed.
      PMID: 19857837 [PubMed - as supplied by publisher]
    • Medial collateral ligament injuries of the knee: current treatment concepts.

      Current reviews in musculoskeletal medicine 2008 Jun

      Authors: Chen L, Kim PD, Ahmad CS, Levine WN
      The medial collateral ligament is one of the most commonly injured ligaments of the knee. Most injuries result from a valgus force on the knee. The increased participation in football, ice hockey, and skiing has all contributed to the increased frequency of MCL injuries. Prophylactic knee bracing in contact sports may prevent injury; however, performance may suffer. The majority of patients who sustain an MCL injury will achieve their pre-injury activity level with non-operative treatment alone; however, those with combined ligamentous injuries may require acute operative care. Accurate characterization of each aspect of the injury will help to determine the optimum treatment plan.
      PMID: 19468882 [PubMed - as supplied by publisher]
    • Vascularized bone grafting from the base of the second metacarpal for persistent distal radius nonunion: a case report.

      Journal of orthopaedic trauma 2005 Aug

      Authors: Crow SA, Chen L, Lee JH, Rosenwasser MP
      Although fractures of the distal radius are relatively common, nonunion is a rare complication. We report a case of a distal radius nonunion in a healthy 51-year-old woman who was involved in a motor vehicle accident. Initial attempts to treat the nonunion with open reduction and internal fixation and corticocancellous bone grafting from the iliac crest failed. Preservation of wrist motion was of considerable importance and wrist arthrodesis was deferred. Treatment of the nonunion with a vascularized bone graft from the base of the second metacarpal, combined with biplanar stable fixation and allogenic bone graft, resulted in union of the fracture and a good functional outcome.
      PMID: 16056082 [PubMed - as supplied by publisher]
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