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Marx, Robert G.

https://orcid.org/0000-0002-2894-0198

Mayo Clinic

Hospital for Special Surgery

Citations 23

Association Between Baseline Meniscal Symptoms and Outcomes of Operative and Nonoperative Treatment of Meniscal Tear in Patients With Osteoarthritis
MacFarlane, Lindsey A. , Yang, Heidi Y. , Collins, Jamie E. , Brophy, Robert H. , Cole, Brian J. , Mandl, Lisa A. , Marx, Robert G. , Levy, Bruce A. , Safran‐Norton, Clare E., Wright, John, Wright, Rick W. , Mandl, Lisa A , Losina, Elena , Brophy, Robert H. , Collins, Jamie E , Spindler, Kurt P , Guermazi, Ali , Jones, Morgan H. , Martin, Scott D. , Marx, Robert G. , Stuart, Michael J. , Losina, Elena , Katz, Jeffrey N.

Arthritis Care & Research | March 2, 2021 | Volume: 74 | Issue: 8 | Pages: 1384-1390

10.1002/acr.24588 Get It

ObjectivePatients with meniscal tears reporting meniscal symptoms such as catching or locking have traditionally undergone arthroscopy. The present study was undertaken to investigate whether patients with meniscal tears who report meniscal symptoms have greater improvement with arthroscopic partial meniscectomy (APM) than physical therapy (PT).MethodsWe used data from the Meniscal Tear in Osteoarthritis Research (MeTeOR) trial, which randomized participants with knee osteoarthritis (OA) and meniscal tear to APM or PT. The frequency of each meniscal symptom (clicking, catching, popping, intermittent locking, giving way, swelling) was measured at baseline and 6 months. We used linear regression models to determine whether the difference in improvement in Knee Injury and Osteoarthritis Outcome Score (KOOS) pain score at 6 months between patients treated with APM versus PT was modified by the presence of each meniscal symptom. We also determined the percentage of participants with resolution of meniscal symptoms by treatment group.ResultsWe included 287 participants. The presence (versus absence) of any of the meniscal symptoms did not modify the improvement in KOOS pain score between APM versus PT by >0.5 SD (all P interaction >0.05). APM led to greater resolution of intermittent locking and clicking than PT (locking 70% versus 46%, clicking 41% versus 25%). No difference in resolution of the other meniscal symptoms was observed.ConclusionMeniscal symptoms were not associated with improved pain relief. Although symptoms of clicking and intermittent locking had a greater reduction in the APM group, the presence of meniscal symptoms in isolation should not inform clinical decisions surrounding APM versus PT in patients with meniscal tear and knee OA.
Rate of infection following revision anterior cruciate ligament reconstruction and associated patient‐ and surgeon‐dependent risk factors: Retrospective results from MOON and MARS data collected from 2002 to 2011
Group, MARS, Brophy, Robert H. , Wright, Rick W. , Huston, Laura J. , Haas, Amanda K. , Anderson, Allen F., Cooper, Daniel E. , Dunn, Warren R. , Lantz, Brett A., Mann, Barton J., Albright, John P., Amendola, Annunziato, Andrish, Jack T. , Annunziata, Christopher C., Arciero, Robert A. , Bach, Bernard R. , Baker, Champ L., Bartolozzi, Arthur R. , Baumgarten, Keith M. , Bechler, Jeffery R., Berg, Jeffrey H., Bernas, Geoffrey A., Brockmeier, Stephen F. , Bush‐Joseph, Charles A., Butler, J. Brad, Carey, James L. , Carpenter, James E. , Cole, Brian J. , Cox, Charles L. , Creighton, R. Alexander , Dahm, Diane L., Flanigan, David C. , Frederick, Robert W., Ganley, Theodore J. , Garofoli, Elizabeth A. , Gatt, Charles J. , Gecha, Steven R., Giffin, J. Robert , Hame, Sharon L. , Hannafin, Jo A., Harner, Christopher D. , Harris, Norman Lindsay, Hechtman, Keith S., Hershman, Elliott B., Hoellrich, Rudolf G., Hosea, Timothy M., Johnson, David C. , Johnson, Timothy S. , Kaeding, Christopher C. , Kamath, Ganesh V. , Klootwyk, Thomas E., Levy, Bruce A. , Benjamin, Chunbong, Maiers, G. Peter, Marx, Robert G. , Matava, Matthew J. , Mathien, Gregory M., McAllister, David R. , McCarty, Eric C. , McCormack, Robert G. , Miller, Bruce S. , Nissen, Carl W. , O’Neill, Daniel F., Parker, Richard D., Purnell, Mark L., Ramappa, Arun J. , Rauh, Michael A. , Rettig, Arthur C., Sekiya, Jon K., Sherman, Orrin H. , Li, Xulei, Slauterbeck, James R., Smith, Matthew V. , Spang, Jeffrey T. , Svoboda, LTC Steven J., Taft, Timothy N., Tenuta, Joachim J., Tingstad, Edwin M., Vidal, Armando F. , Viskontas, Darius G., White, Richard A., Williams, James S., Wolcott, Michelle L., Wolf, Brian R. , York, James J. , Svoboda, Steven J. , Brophy, Robert H. , McCarty, Eric C , Group, MARS, Allen, Christina R. , DeBerardino, Thomas M. , Mann, Barton, Spindler, Kurt P , Stuart, Michael J., Campbell, John , Cooper, Jonathan M., David, Tal S. , Johnson, David C., Jones, Morgan H. , Owens, Brett D. , Shea, Kevin G. , Li, Xulei

Journal of Orthopaedic Research | October 1, 2020 | Volume: 39 | Issue: 2 | Pages: 274-280

10.1002/jor.24871 Get It

AbstractInfection is a rare occurrence after revision anterior cruciate ligament reconstruction (rACLR). Because of the low rates of infection, it has been difficult to identify risk factors for infection in this patient population. The purpose of this study was to report the rate of infection following rACLR and assess whether infection is associated with patient‐ and surgeon‐dependent risk factors. We reviewed two large prospective cohorts to identify patients with postoperative infections following rACLR. Age, sex, body mass index (BMI), smoking status, history of diabetes, and graft choice were recorded for each patient. The association of these factors with postoperative infection following rACLR was assessed. There were 1423 rACLR cases in the combined cohort, with 9 (0.6%) reporting postoperative infections. Allografts had a higher risk of infection than autografts (odds ratio, 6.8; 95% CI, 0.9–54.5; p = .045). Diabetes (odds ratio, 28.6; 95% CI, 5.5–149.9; p = .004) was a risk factor for infection. Patient age, sex, BMI, and smoking status were not associated with risk of infection after rACLR.
Five‐Year Outcome of Operative and Nonoperative Management of Meniscal Tear in Persons Older Than Forty‐Five Years
Katz, Jeffrey N. , Shrestha, Swastina , Marx, Robert G. , Mandl, Lisa A. , Levy, Bruce A. , MacFarlane, Lindsey A. , Silva, Genevieve S. , Investigators, METEOR, Brophy, Robert H. , Losina, Elena , MacFarlane, Lindsey A , Collins, Jamie E , Brophy, Robert H. , Katz, Jeffrey N , Losina, Elena , Jones, Morgan H. , Marx, Robert G. , Spindler, Kurt P , Investigators, METEOR

Arthritis & Rheumatology | August 20, 2019 | Volume: 72 | Issue: 2 | Pages: 273-281

10.1002/art.41082 Get It

ObjectiveTo determine the 5‐year outcome of treatment for meniscal tear in osteoarthritis.MethodsWe examined 5‐year follow‐up data from the Meniscal Tear in Osteoarthritis Research trial (METEOR) of physical therapy versus arthroscopic partial meniscectomy. We performed primary intent‐to‐treat (ITT) and secondary as‐treated analyses. The primary outcome measure was the Knee Injury and Osteoarthritis Outcome Score (KOOS) pain scale; total knee replacement (TKR) was a secondary outcome measure. We used piecewise linear mixed models to describe change in KOOS pain. We calculated 5‐year cumulative TKR incidence and used a Cox model to estimate hazard ratios (HRs) for TKR, with 95% confidence intervals (95% CIs).ResultsThree hundred fifty‐one participants were randomized. In the ITT analysis, the KOOS pain scores were ~46 (scale of 0 [no pain] to 100 [most pain]) at baseline in both groups. Pain scores improved substantially in both groups over the first 3 months, continued to improve through the next 24 months (to ~18 in each group), and were stable at 24–60 months. Results of the as‐treated analyses of the KOOS pain score were similar. Twenty‐five participants (7.1% [95% CI 4.4–9.8%]) underwent TKR over 5 years. In the ITT model, the HR for TKR was 2.0 (95% CI 0.8–4.9) for subjects randomized to the arthroscopic partial meniscectomy group, compared to those randomized to the physical therapy group. In the as‐treated analysis, the HR for TKR was 4.9 (95% CI 1.1–20.9) for subjects ultimately treated with arthroscopic partial meniscectomy, compared to those treated nonoperatively.ConclusionPain improved considerably in both groups over 60 months. While ITT analysis revealed no statistically significant differences following TKR, greater frequency of TKR in those undergoing arthroscopic partial meniscectomy merits further study.
Early Magnetic Resonance Imaging–Based Changes in Patients With Meniscal Tear and Osteoarthritis: Eighteen‐Month Data From a Randomized Controlled Trial of Arthroscopic Partial Meniscectomy Versus Physical Therapy
Collins, Jamie E. , Marx, Robert G. , Jarraya, Mohamed , Levy, Bruce A. , Mandl, Lisa A. , Wright, Rick W. , Group, the MeTeOR Investigator, Brophy, Robert H. , Losina, Elena , Brophy, Robert H. , Collins, Jamie E , Losina, Elena , Marx, Robert G. , Guermazi, Ali , Jones, Morgan H. , Martin, Scott D. , Spindler, Kurt P , Katz, Jeffrey N. , Group, the MeTeOR Investigator

Arthritis Care & Research | April 1, 2019 | Volume: 72 | Issue: 5 | Pages: 630-640

10.1002/acr.23891 Get It

ObjectiveThe present study was undertaken to evaluate changes in knee magnetic resonance imaging (MRI) findings over the course of 18 months in subjects with osteoarthritic change and meniscal tear treated with arthroscopic partial meniscectomy (APM) or nonoperatively with physical therapy (PT).MethodsWe used 18‐month follow‐up data from the Meniscal Tear in Osteoarthritis Research Trial. MRI results were read with reference to the MRI Osteoarthritis Knee Score. We focused on 18‐month change in bone marrow lesions (BMLs), cartilage thickness, cartilage surface area, osteophyte size, effusion‐synovitis, and Hoffa‐synovitis. We used multinomial logistic regression to assess associations between MRI‐based changes in each feature and treatment type.ResultsA total of 351 subjects were randomized, and 225 had both baseline and 18‐month MRI results. In both treatment groups, patients experienced substantial changes in several MRI‐based markers. In 60% of the APM group, versus 33% of the PT group, cartilage surface area damage advanced in ≥2 subregions (adjusted odds ratio 4.2 [95% confidence interval 2.0–9.0). Patients who underwent APM also had greater advancement in scores for osteophytes and effusion‐synovitis. We did not find significant associations between treatment type and change in cartilage thickness, BMLs, or Hoffa‐synovitis.ConclusionThis cohort of patients with meniscal tear and osteoarthritis showed marked advancement in MRI‐based features over 18 months. Patients treated with APM showed more advancement in some features compared to those treated nonoperatively. The clinical relevance of these early findings is unknown and requires further study.
Relationship Between Patient‐Reported Swelling and Magnetic Resonance Imaging–Defined Effusion‐Synovitis in Patients With Meniscus Tears and Knee Osteoarthritis
MacFarlane, Lindsey A. , Yang, Heidi Y. , Collins, Jamie E. , Mandl, Lisa A. , Levy, Bruce A. , Marx, Robert G. , Safran‐Norton, Clare E., Brophy, Robert H. , Losina, Elena , Brophy, Robert H. , Collins, Jamie E , Guermazi, Ali , Marx, Robert G. , Losina, Elena , Katz, Jeffrey N.

Arthritis Care & Research | May 4, 2018 | Volume: 71 | Issue: 3 | Pages: 385-389

10.1002/acr.23592 Get It

Objective Synovitis is a prevalent feature in patients with knee osteoarthritis ( OA ) and meniscal tear and is associated with pain and cartilage damage. Patient‐reported swelling is also prevalent in this population. The aim of this study was to investigate the cross‐sectional association between patient‐reported swelling and effusion‐synovitis detected by magnetic resonance imaging ( MRI ) in patients with OA and meniscal tear. Methods We used baseline data from a multicenter, randomized controlled trial, Meniscal Tear in Osteoarthritis Research ( METEOR ). MRI ‐identified effusion‐synovitis, a proxy for effusion and synovitis on noncontrast MRI s, was graded as none/small versus medium/large. Using MRI ‐identified effusion‐synovitis as the gold standard, we assessed the sensitivity, specificity, and positive predictive value of patient self‐reported swelling in the previous week (none, intermittent, constant) to detect effusion and synovitis. Results We analyzed data from 276 patients. Twenty‐five percent of patients reported no swelling, 40% had intermittent swelling, and 36% had constant swelling. Fifty‐two percent had MRI ‐identified medium/large–grade effusion‐synovitis. As compared with MRI ‐identified effusion‐synovitis, any patient‐reported swelling (versus none) had a sensitivity of 84% (95% confidence interval [95% CI ] 77–89), a specificity of 34% (95% CI 26–43), and a positive predictive value of 57% (95% CI 54–61). A history of constant swelling (versus none or intermittent) showed a sensitivity of 46% (95% CI 37–54), a specificity of 75% (95% CI 67–82), and a positive predictive value of 66% (95% CI 58–74). Conclusion We found that the sensitivity and specificity of patient‐reported swelling were modest when compared with effusion‐synovitis detected by MRI . These data urge caution against using patient‐reported swelling as a proxy of inflammation manifesting as effusion‐synovitis.
Effects of Surgical Factors on Cartilage Can Be Detected Using Quantitative Magnetic Resonance Imaging After Anterior Cruciate Ligament Reconstruction
Amano, Keiko , Li, Alan , Pedoia, Valentina , Krych, Aaron J. , Li, Xiaojuan , Benjamin, C. , Goldring, Steven R., Hannafin, Jo A., Marx, Robert G. , Nawabi, Danyal H. , Shah, Parina, Warren, Russell F. , Amrami, Kimberly K. , Felmlee, Joel P. , Frick, Matthew A., Williams, Steven L. , Kretzchmar, Martin, Okazaki, Narihiro , Russell, Colin, Savic, Dragana , Schwaiger, Benedikt J. , Cheong, Maxwell, Hardin, John , Koff, Matthew F. , Link, Thomas M. , Potter, Hollis G. , Rodeo, Scott A. , Majumdar, Sharmila , Goldring, Mary B. , Otero, Miguel , Stuart, Michael James , Lansdown, Drew Anderson , Russell, Colin, Su, Favian , Wyatt, Cory R. , Krych, Aaron J

The American Journal of Sports Medicine | January 28, 2017 | Volume: 45 | Issue: 5 | Pages: 1075-1084

10.1177/0363546516677794 Get It

Background: Quantitative magnetic resonance (qMR) can be used to measure macromolecules in tissues and is a potential method of observing early cartilage changes in the development of posttraumatic osteoarthritis. Hypothesis/Purpose: We hypothesized that specific patient and surgical factors affecting cartilage matrix composition after anterior cruciate ligament (ACL) reconstruction (ACLR) can be detected using T1ρ and T2 relaxation times. Our purpose was to demonstrate this ability in a multicenter feasibility study. Study Design: Case series; Level of evidence, 4. Methods: A total of 54 patients who underwent ACLR underwent bilateral MRI at baseline before surgery and 6 months postoperatively. Operative findings were recorded. T1ρ and T2 relaxation times were calculated for 6 cartilage regions: the medial femur, lateral femur, medial tibia, lateral tibia, patella, and trochlea. A paired t test compared relaxation times at baseline and 6 months, univariate regression identified regions that influenced patient-reported outcome measures, and analysis of covariance was used to determine the surgical factors that resulted in elevated relaxation times at 6 months. Results: The injured knee had significantly prolonged T1ρ and T2 relaxation times in the tibiofemoral compartment at baseline and 6 months but had shorter values in the patellofemoral compartment compared with the uninjured knee. Prolonged T1ρ and T2 times at 6 months were noted for both the injured and uninjured knees. At 6 months, prolongation of T1ρ and T2 times in the tibial region was associated with lower patient-reported outcome measures. ACLR performed within 30 days of injury had significantly shorter T1ρ times in the tibial regions, and lateral meniscal tears treated with repair had significantly shorter T1ρ times than those treated with excision. Conclusion: Prolonged relaxation times in multiple regions demonstrate how the injury affects the entire joint after an ACL tear. Changes observed in the uninjured knee may be caused by increased loading during rehabilitation, especially in the patellofemoral articular cartilage and distal femur. Relaxation times in the tibial regions may be predictive of patient symptoms at 6 months. These same regions are affected by surgical timing as early as 30 days after injury, but this may partially be reflective of the severity of the preoperative injury and the choice of treatment of meniscal tears.
Effect of High-Grade Preoperative Knee Laxity on Anterior Cruciate Ligament Reconstruction Outcomes
Magnussen, Robert A., Reinke, Emily K. , Huston, Laura J. , Group, MOON, Hewett, Timothy E. , Andrish, Jack T. , Jones, Morgan H. , Parker, Richard D., McCarty, Eric C. , Marx, Robert G. , Amendola, Annunziato , Wolf, Brian R. , Flanigan, David C. , Kaeding, Christopher C. , Brophy, Robert H. , Matava, Matthew J. , Wright, Rick W. , Dunn, Warren R. , Magnussen, Robert A. , Group, MOON, Spindler, Kurt P , Brophy, Robert H. , Jones, Morgan H , McCarty, Eric C

The American Journal of Sports Medicine | August 1, 2016 | Volume: 44 | Issue: 12 | Pages: 3077-3082

10.1177/0363546516656835 Get It

Background: Knee laxity in the setting of suspected anterior cruciate ligament (ACL) injury is frequently assessed through physical examination using the Lachman, pivot-shift, and anterior drawer tests. The degree of laxity noted on these examinations may influence treatment decisions and prognosis. Hypothesis: Increased preoperative knee laxity would be associated with increased risk of subsequent revision ACL reconstruction and worse patient-reported outcomes 2 years postoperatively. Study Design: Cohort study; Level of evidence, 2. Methods: From an ongoing prospective cohort study, 2333 patients who underwent primary isolated ACL reconstruction without collateral or posterior cruciate ligament injury were identified. Patients reported by the operating surgeons as having an International Knee Documentation Committee (IKDC) grade D for Lachman, anterior drawer, or pivot-shift examination were classified as having high-grade laxity. Multiple logistic regression modeling was used to evaluate whether having high-grade preoperative laxity was associated with increased odds of undergoing revision ACL reconstruction within 2 years of the index procedure, controlling for patient age, sex, Marx activity level, level of competition, and graft type. Multiple linear regression modeling was used to evaluate whether having high-grade preoperative laxity was associated with worse IKDC score or Knee injury and Osteoarthritis Outcome Score Knee-Related Quality of Life subscale (KOOS-QOL) scores at a minimum 2 years postoperatively, controlling for baseline score, patient age, ethnicity, sex, body mass index, marital status, smoking status, sport participation, competition level, Marx activity rating score, graft type, and articular cartilage and meniscus status. Results: Pre-reconstruction laxity data were available for 2325 patients (99.7%). Two-year revision data were available for 2259 patients (96.8%), and patient-reported outcomes were available for 1979 patients (84.8%). High-grade preoperative laxity was noted in 743 patients (31.9%). The mean postoperative IKDC score was 81.8 ± 15.9, and the mean KOOS-QOL score was 72.0 ± 22.0. The presence of high-grade pre-reconstruction laxity was associated with significantly increased odds of ACL graft revision (odds ratio [OR] = 1.87 [95% CI, 1.19-2.95]; P = .007). The presence of high-grade pre-reconstruction laxity was not associated with any difference in postoperative IKDC (β = −0.56, P = .44) or KOOS-QOL (β = 0.04, P = .97). Conclusion: The presence of high-grade pre-reconstruction knee laxity as assessed by manual physical examination under anesthesia is associated with significantly increased odds of revision ACL surgery but has no association with patient-reported outcome scores at 2 years after ACL reconstruction.
Does Arthroscopic Knee Surgery Work?
Krych, Aaron J. , Carey, James L. , Marx, Robert G. , Dahm, Diane L., Sennett, Brian J. , Levy, Bruce A. , Marx, Robert G. , Stuart, Michael J. , Krych, Aaron J

Arthroscopy | March 19, 2014 | Volume: 30 | Issue: 5 | Pages: 544-545

10.1016/j.arthro.2014.02.012 Get It

Abstract A recent randomized trial from the Finnish Degenerative Meniscal Lesion Study Group was published in the New England Journal of Medicine and attempted to determine the efficacy of partial meniscectomy without osteoarthritis. Patients were randomized to either arthroscopic partial meniscectomy or sham surgery. The authors concluded that the clinical outcomes after arthroscopic partial meniscectomy were no better than those after the sham surgical procedure. However, there are several important limitations of this trial that make it difficult to generalize to the 700,000 arthroscopic partial meniscectomies performed in the United States each year. In this small sample of 146 patients, patients with traumatic meniscal tears and locking symptoms—those most likely to benefit from a partial meniscectomy—were excluded. In addition, although patients with radiographic arthritis were excluded, most of the patients in the study had degenerative changes at the time of arthroscopy. Therefore it is difficult to determine whether the patients were symptomatic from their chondral degeneration or their degenerative meniscal tear. In our opinion this study does not change the role of surgery in current clinical practice. The primary indication for arthroscopic partial meniscectomy remains symptoms of well‐localized joint line pain with acute onset and mechanical symptoms such as catching or locking that have failed comprehensive nonoperative management.
Accuracy and reliability of determining the isometric point of the knee for multiligament knee reconstruction
Leiter, Jeff , Levy, Bruce A. , Stannard, James P. , Whelan, Daniel B. , Marx, Robert G. , Boyd, Joel L. , MacDonald, Peter B. , Fanelli, Gregory C. , Stuart, Michael J.

Knee Surgery, Sports Traumatology, Arthroscopy | October 5, 2013 | Volume: 22 | Issue: 9 | Pages: 2187-2193

10.1007/s00167-013-2661-2 Get It

AbstractPurposeTo compare the accuracy and reliability of the anatomic and radiographic techniques for identifying the isometric point of the knee.MethodsOnly four specimens were used; however, eight experienced multiligament knee injury surgeons were recruited to address this limitation. Surgeons estimated the isometric point (EIP) on the medial and lateral sides using an anatomic and radiographic method. The x and y coordinates of the EIP were compared to the true isometric point (TIP). T‐tests and interclass correlation coefficients (ICC) were performed to determine the accuracy and reliability between the methods.ResultsThere was no difference in placement of the EIP on the medial side of the knee in the anterior/posterior (x; p = n.s.) and superior/inferior direction (y;p = n.s). The EIP was anterior (p = 0.001) to the TIP with the radiographic method on the lateral side and approached significance (p = 0.05) in the superior/inferior direction. The ICC (95 % CI) for identifying the EIP on the medial side in the anterior/posterior direction using the anatomic method was 0.64 (0.28–0.96) and 0.11 (−0.06 to 0.77) in the superior/inferior direction. Using the radiographic method, the ICC in the anterior/posterior and superior/inferior direction was 0.49 (0.14–0.94) and 0.15 (−0.47 to 0.81), respectively. On the lateral side, the ICC for the anatomic method was 0.84 (0.56–0.99) in the anterior/posterior direction and 0.36 (0.05–0.90) in the superior/inferior direction. Using the radiographic method, the ICC in the anterior/posterior and superior/inferior direction was 0.61 (0.26–0.96) and 0.89 (0.67–0.99), respectively.ConclusionsThere was no difference in accuracy on the medial side of the knee. On the lateral side, the anatomic method was more accurate in the anterior/posterior direction. Reliability was greater in the anterior/posterior direction on both sides of the knee. Surgeons were most likely to place the isometric point anterior and superior to the TIP on both the medial and lateral sides of the knee with either method which has the potential to cause graft lengthening. This should be taken into consideration during reconstruction/repair of the MCL/PMC and LCL/PLC.
Shoulder activity level varies by diagnosis
Brophy, Robert H. , Levy, Bruce A. , Chu, Samuel K. , Dahm, Diane L., Sperling, John W. , Marx, Robert G. , Brophy, Robert H.

Knee Surgery, Sports Traumatology, Arthroscopy | May 29, 2009 | Volume: 17 | Issue: 12 | Pages: 1516-1521

10.1007/s00167-009-0820-2 Get It

AbstractPatient activity level may be an important prognostic variable relating to outcome in patients with shoulder disorders. The purpose of this cross‐sectional study was to test the hypothesis that a shoulder activity scale will detect differences in shoulder activity based on the patient diagnosis and age. A total of 157 patients of four academic orthopedic surgeons with a diagnosis of rotator cuff disease (86), glenohumeral instability (31) or osteoarthritis (40) were asked to fill out a previously validated shoulder activity scale and the ASES shoulder questionnaire. The patient's diagnosis, gender and age were recorded. The activity level was significantly higher in patients with instability than in patients with rotator cuff disease or osteoarthritis. Patients with rotator cuff disease were significantly more active than patients with osteoarthritis. Linear regression of activity level on patient age and diagnosis demonstrated a statistically significant relationship between activity level and both independent variables. Diagnosis influenced activity level independent of age. This is the first study to document diagnosis‐based differences in the shoulder activity level of patients with different shoulder disorders. Shoulder activity level should be evaluated as a prognostic variable in studies of patients with shoulder disorders that may predict outcome and guide treatment in these patients.