Friday, April 29, 2011

Shoulder joint destruction and pain pumps for the shoulder. New study gives better insight in the characteristics of the disease.

There is currently a lot of discussion about the effects of local anesthetic agents in the shoulder joint. Patients often ask: "Was my arthritis caused by the shoulder arthroscopy I had?" Indeed, the young patient with joint destruction due to chondrolysis remains a very difficult problem to treat. Patient and physicians should be aware that to our knowledge the problem of chondrolysis is related to the pain pumps and not the one time joint anesthetic injections. The term chondrolysis refers to an inflammatory destructive process to the cartilage of the shoulder joint due to the toxic effects of the steady and continuous infusion of local anesthetics. Some well respected shoulder surgeons believe that this process may be the final result of a low grade subclinical infection but that theory remains to be proven.

Regardless of the etiology, the shoulder reconstruction in the young and active patient remains a  complicated scenario. Our experience at the University of Washington, Seattle is that patient do not reach the level of satisfaction that we see in patients who are treated with total shoulder replacement for osteoarthritis of the shoulder. Currently, there is no implant that can provide excellent functional result in the very young active patient. In a study that was contacted at the University of Washington in Seattle and published recently in the Journal of Bone and Joint Surgery the risks factors were clearly identified after analyzing arthroscopic procedures of one community surgeon. Ask your doctor to avoid using Marcaine or lidocaine infusion pumps into the joint during the postoperative period. Avoiding such a postoperative infusion may reduce the risk of chondrolysis. This was a Level II study. (about Levels of Evidence please refer to the table below)

Levels of Evidence for Primary Research Question

Levels of Evidence for Primary Research Question1
Types of Studies
Therapeutic Studies—Investigating the Results of Treatment Prognostic Studies—Investigating the Effect of a Patient Characteristic on the Outcome of Disease Diagnostic Studies—Investigating a Diagnostic Test Economic and Decision Analyses—Developing an Economic or Decision Model
Level I



  • High-quality randomized controlled trial with statistically significant difference or no statistically significant difference but narrow confidence intervals











  • Systematic review2 of Level-I randomized controlled trials (and study results were homogeneous3)











  • High-quality prospective study4 (all patients were enrolled at the same point in their disease with ≥80% follow-up of enrolled patients)











  • Systematic review2 of Level-I studies











  • Testing of previously developed diagnostic criteria in series of consecutive patients (with universally applied reference "gold" standard)











  • Systematic review2 of Level-I studies











  • Sensible costs and alternatives; values obtained from many studies; multiway sensitivity analyses











  • Systematic review2 of Level-I studies







  • Level II



  • Lesser-quality randomized controlled trial (e.g., <80% follow-up, no blinding, or improper randomization)











  • Prospective4 comparative study5











  • Systematic review2 of Level-II studies or Level-I studies with inconsistent results











  • Retrospective6 study











  • Untreated controls from a randomized controlled trial











  • Lesser-quality prospective study (e.g., patients enrolled at different points in their disease or <80% follow-up)










  • Systematic review2 of Level-II studies











  • Development of diagnostic criteria on basis of consecutive patients (with universally applied reference "gold" standard)











  • Systematic review2 of Level-II studies











  • Sensible costs and alternatives; values obtained from limited studies; multiway sensitivity analyses











  • Systematic review2 of Level-II studies







  • Level III



  • Case-control study7











  • Retrospective6 comparative study5











  • Systematic review2 of Level-III studies











  • Case-control study7











  • Study of nonconsecutive patients (without consistently applied reference "gold" standard)











  • Systematic review2 of Level-III studies











  • Analyses based on limited alternatives and costs; poor estimates











  • Systematic review2 of Level-III studies







  • Level IV Case series8 Case series



  • Case-control study











  • Poor reference standard











  • No sensitivity analyses







  • Level V Expert opinion Expert opinion Expert opinion Expert opinion
    1. A complete assessment of the quality of individual studies requires critical appraisal of all aspects of the study design.
    2. A combination of results from two or more prior studies.
    3. Studies provided consistent results.
    4. Study was started before the first patient enrolled.
    5. Patients treated one way (e.g., with cemented hip arthroplasty) compared with patients treated another way (e.g., with cementless hip arthroplasty) at the same institution.
    6. Study was started after the first patient enrolled.
    7. Patients identified for the study on the basis of their outcome (e.g., failed total hip arthroplasty), called "cases," are compared with those who did not have the outcome (e.g., had a successful total hip arthroplasty), called "controls."
    8. Patients treated one way with no comparison group of patients treated another way.
    This chart was adapted from material published by the Centre for Evidence-Based Medicine, Oxford, UK. For more information, please see www.cebm.net.

    Risk Factors for Chondrolysis of the Glenohumeral Joint: A Study of Three Hundred and Seventy-five Shoulder Arthroscopic Procedures in the Practice of an Individual Community Surgeon.

    Source

    Department of Orthopedics and Sports Medicine, University of Washington Medical Center, Box 356500, 1959 N.E. Pacific Street, Seattle, WA 98195. matsen@u.washington.edu